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Sample records for integrated two-stage liquefaction

  1. Two-stage liquefaction of a Spanish subbituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, M.T.; Fernandez, I.; Benito, A.M.; Cebolla, V.; Miranda, J.L.; Oelert, H.H. (Instituto de Carboquimica, Zaragoza (Spain))

    1993-05-01

    A Spanish subbituminous coal has been processed in two-stage liquefaction in a non-integrated process. The first-stage coal liquefaction has been carried out in a continuous pilot plant in Germany at Clausthal Technical University at 400[degree]C, 20 MPa hydrogen pressure and anthracene oil as solvent. The second-stage coal liquefaction has been performed in continuous operation in a hydroprocessing unit at the Instituto de Carboquimica at 450[degree]C and 10 MPa hydrogen pressure, with two commercial catalysts: Harshaw HT-400E (Co-Mo/Al[sub 2]O[sub 3]) and HT-500E (Ni-Mo/Al[sub 2]O[sub 3]). The total conversion for the first-stage coal liquefaction was 75.41 wt% (coal d.a.f.), being 3.79 wt% gases, 2.58 wt% primary condensate and 69.04 wt% heavy liquids. The heteroatoms removal for the second-stage liquefaction was 97-99 wt% of S, 85-87 wt% of N and 93-100 wt% of O. The hydroprocessed liquids have about 70% of compounds with boiling point below 350[degree]C, and meet the sulphur and nitrogen specifications for refinery feedstocks. Liquids from two-stage coal liquefaction have been distilled, and the naphtha, kerosene and diesel fractions obtained have been characterized. 39 refs., 3 figs., 8 tabs.

  2. Transport fuels from two-stage coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Benito, A.; Cebolla, V.; Fernandez, I.; Martinez, M.T.; Miranda, J.L.; Oelert, H.; Prado, J.G. (Instituto de Carboquimica CSIC, Zaragoza (Spain))

    1994-03-01

    Four Spanish lignites and their vitrinite concentrates were evaluated for coal liquefaction. Correlationships between the content of vitrinite and conversion in direct liquefaction were observed for the lignites but not for the vitrinite concentrates. The most reactive of the four coals was processed in two-stage liquefaction at a higher scale. First-stage coal liquefaction was carried out in a continuous unit at Clausthal University at a temperature of 400[degree]C at 20 MPa hydrogen pressure and with anthracene oil as a solvent. The coal conversion obtained was 75.41% being 3.79% gases, 2.58% primary condensate and 69.04% heavy liquids. A hydroprocessing unit was built at the Instituto de Carboquimica for the second-stage coal liquefaction. Whole and deasphalted liquids from the first-stage liquefaction were processed at 450[degree]C and 10 MPa hydrogen pressure, with two commercial catalysts: Harshaw HT-400E (Co-Mo/Al[sub 2]O[sub 3]) and HT-500E (Ni-Mo/Al[sub 2]O[sub 3]). The effects of liquid hourly space velocity (LHSV), temperature, gas/liquid ratio and catalyst on the heteroatom liquids, and levels of 5 ppm of nitrogen and 52 ppm of sulphur were reached at 450[degree]C, 10 MPa hydrogen pressure, 0.08 kg H[sub 2]/kg feedstock and with Harshaw HT-500E catalyst. The liquids obtained were hydroprocessed again at 420[degree]C, 10 MPa hydrogen pressure and 0.06 kg H[sub 2]/kg feedstock to hydrogenate the aromatic structures. In these conditions, the aromaticity was reduced considerably, and 39% of naphthas and 35% of kerosene fractions were obtained. 18 refs., 4 figs., 4 tabs.

  3. Two-stage alkaline hydrothermal liquefaction of wood to biocrude in a continuous bench-scale system

    DEFF Research Database (Denmark)

    Sintamarean, Iulia-Maria; Grigoras, Ionela; Jensen, Claus Uhrenholt

    2017-01-01

    unit. In total, 100 kg of wood paste with 25% dry matter is processed at 400 °C and 30 MPa, demonstrating the usefulness of this two-stage liquefaction strategy. An additional advantage liquefaction of such pretreated wood shows increased biocrude yields with approximately 10% compared to the case...

  4. Two-stage coal liquefaction without gas-phase hydrogen

    Science.gov (United States)

    Stephens, H.P.

    1986-06-05

    A process is provided for the production of a hydrogen-donor solvent useful in the liquefaction of coal, wherein the water-gas shift reaction is used to produce hydrogen while simultaneously hydrogenating a donor solvent. A process for the liquefaction of coal using said solvent is also provided. The process enables avoiding the use of a separate water-gas shift reactor as well as high pressure equipment for liquefaction. 3 tabs.

  5. Kinetics of coal liquefaction during heating-up and isothermal stages

    Energy Technology Data Exchange (ETDEWEB)

    Xian Li; Haoquan Hu; Shengwei Zhu; Shuxun Hu; Bo Wu; Meng Meng [Dalian University of Technology, Dalian (China). Institute of Coal Chemical Engineering

    2008-04-15

    Direct liquefaction of Shenhua bituminous coal was carried out in a 500 ml autoclave with iron catalyst and coal liquefaction cycle-oil as solvent at initial hydrogen of 8.0 MPa, residence time of 0-90 min. To investigate the liquefaction kinetics, a model for heating-up and isothermal stages was developed to estimate the rate constants of both stages. In the model, the coal was divided into three parts, easy reactive part, hard reactive part and unreactive part, and four kinetic constants were used to describe the reaction mechanism. The results showed that the model is valid for both heating-up and isothermal stages of liquefaction perfectly. The rate-controlled process for coal liquefaction is the reaction of preasphaltene plus asphaltene (PAA) to oil plus gas (O + G). The upper-limiting conversion of isothermal stage was estimated by the kinetic calculation. 21 refs., 4 figs., 4 tabs.

  6. Catalyst dispersion and activity under conditions of temperature-staged liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Davis, A.; Schobert, H.H.; Mitchell, G.D.; Artok, L.

    1993-02-01

    This research program involves the investigation of the use of highly dispersed catalyst precursors for the pretreatment of coals by mild hydrogenation. During the course of this effort solvent preswelling of the coal was evaluated as a means of deeply impregnating catalysts into coal, active phases of catalysts under reaction conditions were studied and the impact of these techniques were evaluated during pretreatment and temperature-staged liquefaction. Two coals, a Texas subbituminous and a Utah high volatile A bituminous, were used to examine the effects of solvent swelling pretreatment and catalyst impregnation on conversion behavior at 275[degrees]C, representative of the first, low-temperature stage in a temperature-staged liquefaction reaction. Ferrous sulfate, iron pentacarbonyl, ammonium tetrathiomolybdate, and molybdenum hexacarbonyl were used as catalyst precursors. Without swelling pretreatment, impregnation of both coals increased conversion, mainly through increased yields of preasphaltenes.

  7. EXPLORATORY RESEARCH ON NOVEL COAL LIQUEFACTION CONCEPT

    Energy Technology Data Exchange (ETDEWEB)

    Brandes, S.D.; Winschel, R.A.

    1998-11-30

    The report presents a summary the work performed under DOE Contract No. DE-AC22-95PC95050. Investigations performed under Task 4--Integrated Flow Sheet Testing are detailed. In this program, a novel direct coal liquefaction technology was investigated by CONSOL Inc. with the University of Kentucky Center for Applied Energy Research and LDP Associates. The process concept explored consists of a first-stage coal dissolution step in which the coal is solubilized by hydride ion donation. In the second stage, the products are catalytically upgraded to refinery feedstocks. Integrated first-stage and solids-separation steps were used to prepare feedstocks for second-stage catalytic upgrading. An engineering and economic evaluation was conducted concurrently with experimental work throughout the program. Approaches to reduce costs for a conceptual commercial plant were recommended at the conclusion of Task 3. These approaches were investigated in Task 4. The economic analysis of the process as it was defined at the conclusion of Task 4, indicates that the production of refined product (gasoline) via this novel direct liquefaction technology is higher than the cost associated with conventional two-stage liquefaction technologies.

  8. Study of initial stage in coal liquefaction. Increase in oil yield with suppression of retrogressive reaction during initial stage; Ekika hanno no shoki katei ni kansuru kenkyu. 1.

    Energy Technology Data Exchange (ETDEWEB)

    Uesugi, K.; Kanaji, M.; Kaneko, T.; Shimasaki, K. [Nippon Brown Coal Liquefaction Co. Ltd., Tokyo (Japan)

    1996-10-28

    For the coal liquefaction, improvement of liquefaction conditions and increase of liquefied oil yield are expected by suppressing the recombination through rapid stabilization of pyrolytic radicals which are formed at the initial stage of liquefaction. Two-stage liquefaction combining prethermal treatment and liquefaction was performed under various conditions, to investigate the effects of reaction conditions on the yields and properties of products as well as to increase liquefied oil yield. Consequently, it was found that the catalyst contributes greatly to the hydrogen transfer to coal at the prethermal treatment. High yield of n-hexane soluble fraction with products having low condensation degree could be obtained by combining the prethermal treatment in the presence of hydrogen and catalyst with the concentration of slurry after the treatment. This was considered to be caused by the synergetic effect between the improvement of liquefaction by suppressing polymerization/condensation at the initial stage of reaction through the prethermal treatment and the effective hydrogen transfer accompanied with the improvement of contact efficiency of coal/catalyst by the concentration of slurry at the stage of liquefaction. 4 refs., 8 figs.

  9. Catalyst dispersion and activity under conditions of temperature-staged liquefaction. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Davis, A.; Schobert, H.H.; Mitchell, G.D.; Artok, L.

    1993-02-01

    This research program involves the investigation of the use of highly dispersed catalyst precursors for the pretreatment of coals by mild hydrogenation. During the course of this effort solvent preswelling of the coal was evaluated as a means of deeply impregnating catalysts into coal, active phases of catalysts under reaction conditions were studied and the impact of these techniques were evaluated during pretreatment and temperature-staged liquefaction. Two coals, a Texas subbituminous and a Utah high volatile A bituminous, were used to examine the effects of solvent swelling pretreatment and catalyst impregnation on conversion behavior at 275{degrees}C, representative of the first, low-temperature stage in a temperature-staged liquefaction reaction. Ferrous sulfate, iron pentacarbonyl, ammonium tetrathiomolybdate, and molybdenum hexacarbonyl were used as catalyst precursors. Without swelling pretreatment, impregnation of both coals increased conversion, mainly through increased yields of preasphaltenes.

  10. Thermodynamic analysis and economical evaluation of two 310-80 K pre-cooling stage configurations for helium refrigeration and liquefaction cycle

    Science.gov (United States)

    Zhu, Z. G.; Zhuang, M.; Jiang, Q. F.; Y Zhang, Q.; Feng, H. S.

    2017-12-01

    In 310-80 K pre-cooling stage, the temperature of the HP helium stream reduces to about 80 K where nearly 73% of the enthalpy drop from room temperature to 4.5 K occurs. Apart from the most common liquid nitrogen pre-cooling, another 310-80 K pre-cooling configuration with turbine is employed in some helium cryoplants. In this paper, thermodynamic and economical performance of these two kinds of 310-80 K pre-cooling stage configurations has been studied at different operating conditions taking discharge pressure, isentropic efficiency of turbines and liquefaction rate as independent parameters. The exergy efficiency, total UA of heat exchangers and operating cost of two configurations are computed. This work will provide a reference for choosing 310-80 K pre-cooling stage configuration during design.

  11. Direct liquefaction proof-of-concept facility

    Energy Technology Data Exchange (ETDEWEB)

    Alfred G. Comolli; Peizheng Zhou; HTI Staff

    2000-01-01

    The main objective of the U.S. DOE, Office of Fossil Energy, is to ensure the US a secure energy supply at an affordable price. An integral part of this program was the demonstration of fully developed coal liquefaction processes that could be implemented if market and supply considerations so required, Demonstration of the technology, even if not commercialized, provides a security factor for the country if it is known that the coal to liquid processes are proven and readily available. Direct liquefaction breaks down and rearranges complex hydrocarbon molecules from coal, adds hydrogen, and cracks the large molecules to those in the fuel range, removes hetero-atoms and gives the liquids characteristics comparable to petroleum derived fuels. The current processes being scaled and demonstrated are based on two reactor stages that increase conversion efficiency and improve quality by providing the flexibility to adjust process conditions to accommodate favorable reactions. The first stage conditions promote hydrogenation and some oxygen, sulfur and nitrogen removal. The second stage hydrocracks and speeds the conversion to liquids while removing the remaining sulfur and nitrogen. A third hydrotreatment stage can be used to upgrade the liquids to clean specification fuels.

  12. The direct liquefaction proof of concept program

    Energy Technology Data Exchange (ETDEWEB)

    Comolli, A.G.; Lee, L.K.; Pradhan, V.R.; Stalzer, R.H. [New York & Puritan Avenues, Lawrenceville, NJ (United States)

    1995-12-31

    The goal of the Proof of Concept (POC) Program is to develop Direct Coal Liquefaction and associated transitional technologies towards commercial readiness for economically producing premium liquid fuels from coal in an environmentally acceptable manner. The program focuses on developing the two-stage liquefaction (TSL) process by utilizing geographically strategic feedstocks, commercially feasible catalysts, new prototype equipment, and testing co-processing or alternate feedstocks and improved process configurations. Other high priority objectives include dispersed catalyst studies, demonstrating low rank coal liquefaction without solids deposition, improving distillate yields on a unit reactor volume basis, demonstrating ebullated bed operations while obtaining scale-up data, demonstrating optimum catalyst consumption using new concepts (e.g. regeneration, cascading), producing premium products through on-line hydrotreating, demonstrating improved hydrogen utilization for low rank coals using novel heteroatom removal methods, defining and demonstrating two-stage product properties for upgrading; demonstrating efficient and economic solid separation methods, examining the merits of integrated coal cleaning, demonstrating co-processing, studying interactions between the preheater and first and second-stage reactors, improving process operability by testing and incorporating advanced equipment and instrumentation, and demonstrating operation with alternate coal feedstocks. During the past two years major PDU Proof of Concept runs were completed. POC-1 with Illinois No. 6 coal and POC-2 with Black Thunder sub-bituminous coal. Results from these operations are continuing under review and the products are being further refined and upgraded. This paper will update the results from these operations and discuss future plans for the POC program.

  13. Liquefaction of solid carbonaceous material with catalyst recycle

    Science.gov (United States)

    Gupta, Avinash; Greene, Marvin I.

    1992-01-01

    In the two stage liquefaction of a carbonaceous solid such as coal wherein coal is liquefied in a first stage in the presence of a liquefaction solvent and the first stage effluent is hydrogenated in the presence of a supported hydrogenation catalyst in a second stage, catalyst which has been previously employed in the second stage and comminuted to a particle size distribution equivalent to 100% passing through U.S. 100 Mesh, is passed to the first stage to improve the overall operation.

  14. Coal liquefaction process streams characterization and evaluation: Application of liquid chromatographic separation methods to THF-soluble portions of integrated two-stage coal liquefaction resids

    Energy Technology Data Exchange (ETDEWEB)

    Green, J.B.; Pearson, C.D.; Young, L.L.; Green, J.A. [National Inst. for Petroleum and Energy Research, Bartlesville, OK (United States)

    1992-05-01

    This study demonstrated the feasibility of using non-aqueous ion exchange liquid chromatography (NIELC) for the examination of the tetrahydrofuran (THF)-soluble distillation resids and THF-soluble whole oils derived from direct coal liquefaction. The technique can be used to separate the material into a number of acid, base, and neutral fractions. Each of the fractions obtained by NIELC was analyzed and then further fractionated by high-performance liquid chromatography (HPLC). The separation and analysis schemes are given in the accompanying report. With this approach, differences can be distinguished among samples obtained from different process streams in the liquefaction plant and among samples obtained at the same sampling location, but produced from different feed coals. HPLC was directly applied to one THF-soluble whole process oil without the NIELC preparation, with limited success. The direct HPLC technique used was directed toward the elution of the acid species into defined classes. The non-retained neutral and basic components of the oil were not analyzable by the direct HPLC method because of solubility limitations. Sample solubility is a major concern in the application of these techniques.

  15. Magnetic refrigerator for hydrogen liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Numazawa, T [National Institute for Materials Science, Tsukuba (Japan); Kamlya, K. [Japan Atomic Energy Agency, Naka (Japan); Utaki, T. [Osaka University, Osaka (Japan); Matsumoto, K. [Kanazawa University, Kanazawa (Japan)

    2013-06-15

    This paper reviews the development status of magnetic refrigeration system for hydrogen liquefaction. There is no doubt that hydrogen is one of most important energy sources in the near future. In particular, liquid hydrogen can be utilized for infrastructure construction consisting of storage and transportation. Liquid hydrogen is in cryogenic temperatures and therefore high efficient liquefaction method must be studied. Magnetic refrigeration which uses the magneto-caloric effect has potential to realize not only the higher liquefaction efficiency > 50 %, but also to be environmentally friendly and cost effective. Our hydrogen magnetic refrigeration system consists of Carnot cycle for liquefaction stage and AMR (active magnetic regenerator) cycle for precooling stages. For the Carnot cycle, we develop the high efficient system > 80 % liquefaction efficiency by using the heat pipe. For the AMR cycle, we studied two kinds of displacer systems, which transferred the working fluid. We confirmed the AMR effect with the cooling temperature span of 12 K for 1.8 T of the magnetic field and 6 second of the cycle. By using the simulation, we estimate the total efficiency of the hydrogen liquefaction plant for 10 kg/day. A FOM of 0.47 is obtained in the magnetic refrigeration system operation temperature between 20 K and 77 K including LN2 work input.

  16. The Liquefaction of Hydrogen and Helium Using Small Coolers

    International Nuclear Information System (INIS)

    Green, Michael A.

    2006-01-01

    This report discusses the history of the liquefaction of hydrogen and helium using small coolers. This history dates form the 1960's when two stage GM coolers capable of reaching 7 K were used to liquefy helium and hydrogen by suing an added compressor and J-T circuit. Liquefaction using the added circuit failed to become mainstream because the J-T valve and heat exchanger clogged because of impurities in the gas being liquefied. Liquefaction using a GM cooler without an added J-T circuit proved to be difficult because the first stage was not used to pre-cool the gas coming to the second stage of the cooler. Once the gas being liquefied was pre-cooled using the cooler first stage, improvements in the liquefaction rates were noted. The advent of low temperature pulse tube cooler (down to 2.5 K) permitted one to achieve dramatic improvement is the liquefactions rates for helium. Similar but less dramatic improvements are expected for hydrogen as well. Using the PT-415 cooler, one can expect liquefaction rates of 15 to 20 liters per day for helium or hydrogen provided the heat leak into the cooler and the storage vessel is low. A hydrogen liquefier for MICE is presented at the end of this report

  17. Exergy analysis of helium liquefaction systems based on modified Claude cycle with two-expanders

    Science.gov (United States)

    Thomas, Rijo Jacob; Ghosh, Parthasarathi; Chowdhury, Kanchan

    2011-06-01

    Large-scale helium liquefaction systems, being energy-intensive, demand judicious selection of process parameters. An effective tool for design and analysis of thermodynamic cycles for these systems is exergy analysis, which is used to study the behavior of a helium liquefaction system based on modified Claude cycle. Parametric evaluation using process simulator Aspen HYSYS® helps to identify the effects of cycle pressure ratio and expander flow fraction on the exergetic efficiency of the liquefaction cycle. The study computes the distribution of losses at different refrigeration stages of the cycle and helps in selecting optimum cycle pressures, operating temperature levels of expanders and mass flow rates through them. Results from the analysis may help evolving guidelines for designing appropriate thermodynamic cycles for practical helium liquefaction systems.

  18. Catalytic multi-stage liquefaction of coal at HTI: Bench-scale studies in coal/waste plastics coprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Pradhan, V.R.; Lee, L.K.; Stalzer, R.H. [Hydrocarbon Technologies, Inc., Lawrenceville, NJ (United States)] [and others

    1995-12-31

    The development of Catalytic Multi-Stage Liquefaction (CMSL) at HTI has focused on both bituminous and sub-bituminous coals using laboratory, bench and PDU scale operations. The crude oil equivalent cost of liquid fuels from coal has been curtailed to about $30 per barrel, thus achieving over 30% reduction in the price that was evaluated for the liquefaction technologies demonstrated in the late seventies and early eighties. Contrary to the common belief, the new generation of catalytic multistage coal liquefaction process is environmentally very benign and can produce clean, premium distillates with a very low (<10ppm) heteroatoms content. The HTI Staff has been involved over the years in process development and has made significant improvements in the CMSL processing of coals. A 24 month program (extended to September 30, 1995) to study novel concepts, using a continuous bench scale Catalytic Multi-Stage unit (30kg coal/day), has been initiated since December, 1992. This program consists of ten bench-scale operations supported by Laboratory Studies, Modelling, Process Simulation and Economic Assessments. The Catalytic Multi-Stage Liquefaction is a continuation of the second generation yields using a low/high temperature approach. This paper covers work performed between October 1994- August 1995, especially results obtained from the microautoclave support activities and the bench-scale operations for runs CMSL-08 and CMSL-09, during which, coal and the plastic components for municipal solid wastes (MSW) such as high density polyethylene (HDPE)m, polypropylene (PP), polystyrene (PS), and polythylene terphthlate (PET) were coprocessed.

  19. Techno-economic analysis of solar integrated hydrothermal liquefaction of microalgae

    International Nuclear Information System (INIS)

    Pearce, Matthew; Shemfe, Mobolaji; Sansom, Christopher

    2016-01-01

    Highlights: • Hydrothermal liquefaction and concentrated solar power provide integrated biofuel technology. • Heat kinetics and energy efficiency Aspen plus modelling of CSP and HTL. • Microalgae biofuel minimum fuel sales price of $1.23/kg. - Abstract: Integration of Hydrothermal Liquefaction (HTL) of microalgae biomass with concentrated solar power thermal processing (CSP) for bio-oil production is a potential processing pathway for energy efficient generation of renewable biofuels. Solar HTL infrastructure avoids additional bolt-on components of conventional solar parabolic trough systems used for electricity production including heat transfer fluids, counter current heat exchangers, fluid transfer interconnectivity and electrical power control systems. The absence of such capital intensive additional equipment considerably reduces the production costs of solar HTL biofuels compared to electricity generation from conventional CSP power systems. An economic and market appraisal of variance and system economic resilience is presented. It is hypothesised that the combination of nutrient recycling with HTL/CSP unification has the potential for economically sustainable microalgae bio-oil production. A microalgae biofuel minimum fuel sales price of $1.23/kg has been modelled. Further experimental work would be able to validate this integrated model.

  20. Coal liquefaction in early stage of NEDOL process 1t/d PSU; 1t/d PSU ni okeru ekika shoki hanno ni kansuru kento

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, K.; Kawabata, M.; Mochizuki, M.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Nogami, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan)

    1996-10-28

    To investigate the behavior of coal liquefaction reaction in early stage as a part of studies on the coal liquefaction characteristics using NEDOL process 1 t/d process supporting unit (PSU), coal slurry sample was taken from the outlet of slurry preheater located in the upflow of liquefaction reactors, and was tested. Tanito Harum coal was used for liquefaction. Preheater was operated under the condition of pressure of 170 kg/cm{sup 2}, gas flow rate of 64 Nm{sup 3}/hr, and at temperature up to 410{degree}C at the outlet, in response to the standard test condition. The slurry sample was discharged into a high temperature separator with temperature of 250{degree}C. Liquefaction was not proceeded at the outlet of preheater. Solid residue yielded around 80%, and liquid yielded around 15%. Gases, CO and CO2, and water yielded also small amount around 3%. The solid sample contained much IOM fraction (tetrahydrofuran-insoluble and ash), and the liquid contained much heavy oil fraction. Hydrogenation was not proceeded, and the hydrogen consumption was very low showing below one-tenth of that at the usual operation. Hydrogen sulfide gas was formed at early stage, which suggested that the change of iron sulfide catalyst occur at early stage of liquefaction. 1 ref., 5 figs., 2 tabs.

  1. Survey on development of brown coal liquefaction techniques; Kattan ekika gijutsu ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-09-01

    Described herein are results of literature survey on brown coal liquefaction reactions and elementary techniques. Liquefaction of brown coal in the presence of CO and steam, or CO, H{sub 2} and steam has been investigated. It is not clear by the literature survey whether it is superior to the normal process which uses hydrogen. Brown coal contains moisture at high contents, and the drying techniques are necessary to be developed for its liquefaction. The future coal liquefaction plant will be much larger than the past one, and there are a number of problems to be solved, such as those involved in the designs of large-sized high-pressure slurry pumps, heat exchangers and preheaters. It is also necessary to develop the materials of and production techniques for large reactors which are serviceable under severe conditions. The solid-liquid separation for liquefaction products involves a number of the elementary techniques characteristic of coal liquefaction processes, and needs many technological developments. The one-stage brown coal liquefaction process is compared with the two-stage process for the secondary hydrogenation of SCR, but no clear conclusions are reached. (NEDO)

  2. Report for fiscal 1981 of Sunshine Program coal group. Basic research on Solvolysis liquefaction technology; 1981 nendo solvolysis ekika gijutsu no kiso kenkyu hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-03-01

    Basic research is conducted on the Solvolysis liquefaction process for the purpose of producing from coal an ashless, low-sulfur, pollution-free liquid fuel. In the research on the Solvolysis liquefaction (1st stage liquefaction) of coal using a hydrogenation solvent, the Solvolysis liquefaction of coal is studied, for which a refined Solvolysis pitch containing coal substances and a hydride of solvent refined coal are used as Solvolysis liquefaction solvents for the 1st stage. In the research on the 1st stage liquefaction reaction conditions using a high-temperature closed process, two methods are employed. One is a method that uses a mini-pump type reactor in which a small hermetic container is submerged in a high-temperature solvent for rapid heating and the other is a method that uses a pipe type reactor in which coal slurry is caused to travel through a pipe heated to a high temperature. For the analysis of the 2nd stage liquefaction (hydrogenation) reaction conditions, the properties of the 2nd coal liquid, and the constitution of the 2nd coal liquid, and the for the research on the 1st stage liquefaction capacity, the hydrogenation of anthracene oil and solvent refined coal as recyclable solvent models is studied. (NEDO)

  3. Fractional Multistage Hydrothermal Liquefaction of Biomass and Catalytic Conversion into Hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Cortright, Randy [Virent, Inc., Madison, WI (United States); Rozmiarek, Robert [Virent, Inc., Madison, WI (United States); Dally, Brice [Virent, Inc., Madison, WI (United States); Holland, Chris [Virent, Inc., Madison, WI (United States)

    2017-08-31

    The objective of this project was to develop an improved multistage process for the hydrothermal liquefaction (HTL) of biomass to serve as a new front-end, deconstruction process ideally suited to feed Virent’s well-proven catalytic technology, which is already being scaled up. This process produced water soluble, partially de-oxygenated intermediates that are ideally suited for catalytic finishing to fungible distillate hydrocarbons. Through this project, Virent, with its partners, demonstrated the conversion of pine wood chips to drop-in hydrocarbon distillate fuels using a multi-stage fractional conversion system that is integrated with Virent’s BioForming® process. The majority of work was in the liquefaction task and included temperature scoping, solvent optimization, and separations.

  4. Continuous production of biohythane from hydrothermal liquefied cornstalk biomass via two-stage high-rate anaerobic reactors.

    Science.gov (United States)

    Si, Bu-Chun; Li, Jia-Ming; Zhu, Zhang-Bing; Zhang, Yuan-Hui; Lu, Jian-Wen; Shen, Rui-Xia; Zhang, Chong; Xing, Xin-Hui; Liu, Zhidan

    2016-01-01

    Biohythane production via two-stage fermentation is a promising direction for sustainable energy recovery from lignocellulosic biomass. However, the utilization of lignocellulosic biomass suffers from specific natural recalcitrance. Hydrothermal liquefaction (HTL) is an emerging technology for the liquefaction of biomass, but there are still several challenges for the coupling of HTL and two-stage fermentation. One particular challenge is the limited efficiency of fermentation reactors at a high solid content of the treated feedstock. Another is the conversion of potential inhibitors during fermentation. Here, we report a novel strategy for the continuous production of biohythane from cornstalk through the integration of HTL and two-stage fermentation. Cornstalk was converted to solid and liquid via HTL, and the resulting liquid could be subsequently fed into the two-stage fermentation systems. The systems consisted of two typical high-rate reactors: an upflow anaerobic sludge blanket (UASB) and a packed bed reactor (PBR). The liquid could be efficiently converted into biohythane via the UASB and PBR with a high density of microbes at a high organic loading rate. Biohydrogen production decreased from 2.34 L/L/day in UASB (1.01 L/L/day in PBR) to 0 L/L/day as the organic loading rate (OLR) of the HTL liquid products increased to 16 g/L/day. The methane production rate achieved a value of 2.53 (UASB) and 2.54 L/L/day (PBR), respectively. The energy and carbon recovery of the integrated HTL and biohythane fermentation system reached up to 79.0 and 67.7%, respectively. The fermentation inhibitors, i.e., 5-hydroxymethyl furfural (41.4-41.9% of the initial quantity detected) and furfural (74.7-85.0% of the initial quantity detected), were degraded during hydrogen fermentation. Compared with single-stage fermentation, the methane process during two-stage fermentation had a more efficient methane production rate, acetogenesis, and COD removal. The microbial distribution

  5. Coal liquefaction becomes viable

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-11-15

    In 2003 the May/June issue of CoalTrans International speculated that coal liquefaction would become viable due to falling coal prices. This has not proved the case but the sustained high oil price is sparking new interest. A survey by Energy Intelligence and Marketing Research during November 2005 revealed a growth in the number of projects under development or at the feasibility stage. The article reports projects in China, the USA, Australia, New Zealand, the Philippines and India. China is commissioning the first wave of large liquefaction plants. The key question is whether other countries, particularly the USA, will follow.

  6. Techno-economic Assessment of Integrated Hydrothermal Liquefaction and Combined Heat and Power Production from Lignocellulose Residues

    Directory of Open Access Journals (Sweden)

    Mohamed Magdeldin

    2018-03-01

    Full Text Available Waste biomass as a mean for global carbon dioxide emissions mitigation remains under-utilized. This is mainly due to the low calorific value of virgin feedstock, characterized generally with high moisture content. Aqueous processing, namely hydrothermal liquefaction in subcritical water conditions, has been demonstrated experimentally to thermally densify solid lignocellulose into liquid fuels without the pre-requisite and energy consuming drying step. This study presents a techno-economic evaluation of an integrated hydrothermal liquefaction system with downstream combined heat and power production from forest residues. The utilization of the liquefaction by-products and waste heat from the elevated processing conditions, coupled with the chemical upgrading of the feedstock enables the poly-generation of biocrude, electricity and district heat. The plant thermal efficiency increases by 3.5 to 4.6% compared to the conventional direct combustion case. The economic assessment showed that the minimum selling price of biocrude, based on present co-products market prices, hinders commercialization and ranges between 138 EUR to 178 EUR per MWh. A sensitivity analysis and detailed discussion on the techno-economic assessment results are presented for the different process integration and market case scenarios.

  7. Prospect of coal liquefaction in Indonesia

    International Nuclear Information System (INIS)

    Hartiniati; Dasuki, A.S.; Artanto, Yu.; Sulaksono, D.; Gunanjar

    1997-01-01

    With the current known oil reserves of about 11 billion barrel and annual production of approximately 500 million barrel, the country's oil reserves will be depleted by 2010, and Indonesia would have become net oil importer if no major oil fields be found somewhere in the archipelago. Under such circumstances the development of new sources of liquid fuel becomes a must, and coal liquefaction can be one possible solution for the future energy problem in Indonesia, particularly in the transportation sector due to the availability of coal in huge amount. This paper present the prospect of coal liquefaction in Indonesia and look at the possibility of integrating the process with HTR as a heat supplier. Evaluation of liquidability of several low grade Indonesian coals will also be presented. Coal from South Banko-Tanjung Enim is found to be one of the most suitable coal for liquefaction. Several studies show that an advanced coal liquefaction technology recently developed has the potential to reduce not only the environmental impact but also the production cost. The price of oil produced in the year 2000 is expected to reach US $ 17.5 ∼ 19.2/barrel and this will compete with the current oil price. Not much conclusion can be drawn from the idea of integrating HTR with coal liquefaction plant due to limited information available. (author). 7 figs, 3 tabs

  8. The sequence of sediment behaviour during wave-induced liquefaction

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Hatipoglu, Figen; Fredsøe, Jørgen

    2006-01-01

    to be in agreement with recent centrifuge wave-tank experiments. As for the final stage of the sequence of processes (formation of ripples), the ripple steepness (normalized with the angle of repose) for sediment with liquefaction history is found to be the same as that in sediment with no liquefaction history.......This paper presents the results of an experimental investigation of the complete sequence of sediment behaviour beneath progressive waves. The sediment was silty with d(50) = 0.060 mm. Two kinds of measurements were carried out: pore-water pressure measurements (across the sediment depth...... of liquefaction and compaction fronts in the sediment and (iii) the characteristics of the orbital motion of the liquefied sediment including the motion of the interface between the water body and the sediment. The ranges of the various quantities in the tests were: wave height, H = 9-17 cm, wave period, T = 1...

  9. Potential of soil liquefaction at Perlis, northern region of Malalysia

    Science.gov (United States)

    Ghazaly, Zuhayr Md; Rahim, Mustaqqim Abdul; Nasir, Mohamad Amzar Bin Mhd; Isa, Nur Fitriah; Zaki, Mohd Faiz Mohammad; Hassan, Zulkarnain Bin; Ismail, Zul-Atfi Bin

    2017-09-01

    Soil liquefaction is earthquake's secondary effect which could cause fatal damages and structures instability. Despite Malaysia been located in stable zone of Pacific Ring of Fire, few significant surrounded quakes like Sumatra-Andaman earthquake had prompted Malaysian's public concern, especially in Perlis area, on local seismic resistant. Hence, this research presents the analysis result of liquefaction potential of the soils, as the secondary effect of earthquake, within Perlis, northern region of Malaysia; the next strong and sustainable metropolis by using semi-empirical procedures introduced by Seed and Idriss. The study consists of two stages which were determination of the local geological and geotechnical site conditions within Perlis and analysis of soil liquefaction susceptibility by using various methods and liquefaction potential by using Simplified Procedure developed by Seed and Idriss on stress approach. There were consist of four phases implemented in order to achieve the objectives targeted for the study after problem being identified. Firstly, a comprehensive review of literature on liquefaction at Perlis was carried out. Second phase was data collection process that includes collection of Site Investigation (SI) report. Thirdly, data analysis was carried out by utilizing suitable method. The final phase was to draw conclusion and recommendation for this study. It can be concluded that the overall Perlis due to earthquake moment magnitude below 7.5 has no potential to soil liquefaction. However, with the range of liquefaction potential of 1.60 to 5.64 in Kuala Perlis area, it is liquefiable. The development of liquefaction severity map of Perlis, Malaysia in this research, may be used by others as a reference for seismic design and standard safety measures as well as for further research work.

  10. Assessment of liquefaction potential during earthquakes by arias intensity

    Science.gov (United States)

    Kayen, R.E.; Mitchell, J.K.

    1997-01-01

    An Arias intensity approach to assess the liquefaction potential of soil deposits during earthquakes is proposed, using an energy-based measure of the severity of earthquake-shaking recorded on seismograms of the two horizontal components of ground motion. Values representing the severity of strong motion at depth in the soil column are associated with the liquefaction resistance of that layer, as measured by in situ penetration testing (SPT, CPT). This association results in a magnitude-independent boundary that envelopes initial liquefaction of soil in Arias intensity-normalized penetration resistance space. The Arias intensity approach is simple to apply and has proven to be highly reliable in assessing liquefaction potential. The advantages of using Arias intensity as a measure of earthquake-shaking severity in liquefaction assessment are: Arias intensity is derived from integration of the entire seismogram wave form, incorporating both the amplitude and duration elements of ground motion; all frequencies of recorded motion are considered; and Arias intensity is an appropriate measure to use when evaluating field penetration test methodologies that are inherently energy-based. Predictor equations describing the attenuation of Arias intensity as a function of earthquake magnitude and source distance are presented for rock, deep-stiff alluvium, and soft soil sites.

  11. Liquefaction chemistry and kinetics: Hydrogen utilization studies

    Energy Technology Data Exchange (ETDEWEB)

    Rothenberger, K.S.; Warzinski, R.P.; Cugini, A.V. [Pittsburgh Energy Technology Center, PA (United States)] [and others

    1995-12-31

    The objectives of this project are to investigate the chemistry and kinetics that occur in the initial stages of coal liquefaction and to determine the effects of hydrogen pressure, catalyst activity, and solvent type on the quantity and quality of the products produced. The project comprises three tasks: (1) preconversion chemistry and kinetics, (2) hydrogen utilization studies, and (3) assessment of kinetic models for liquefaction. The hydrogen utilization studies work will be the main topic of this report. However, the other tasks are briefly described.

  12. Design of generic coal conversion facilities: Process release---Direct coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    The direct liquefaction portion of the PETC generic direct coal liquefaction process development unit (PDU) is being designed to provide maximum operating flexibility. The PDU design will permit catalytic and non-catalytic liquefaction concepts to be investigated at their proof-of-the-concept stages before any larger scale operations are attempted. The principal variations from concept to concept are reactor configurations and types. These include thermal reactor, ebullating bed reactor, slurry phase reactor and fixed bed reactor, as well as different types of catalyst. All of these operating modes are necessary to define and identify the optimum process conditions and configurations for determining improved economical liquefaction technology.

  13. Conceptual design of an integrated hydrothermal liquefaction and biogas plant for sustainable bioenergy production

    DEFF Research Database (Denmark)

    Hoffmann, Jessica; Rudra, Souman; Toor, Saqib

    2013-01-01

    Initial process studies carried out in Aspen Plus on an integrated thermochemical conversion process are presented herein. In the simulations, a hydrothermal liquefaction (HTL) plant is combined with a biogas plant (BP), such that the digestate from the BP is converted to a biocrude in the HTL...... grid or for CHP. An estimated 62–84% of the biomass energy can be recovered in the biofuels....

  14. Effect of sulfur or hydrogen sulfide on initial stage of coal liquefaction in tetralin; Sekitan ekika shoki katei ni okeru io to ryuka suiso no hatasu yakuwari

    Energy Technology Data Exchange (ETDEWEB)

    Nakada, M. [Government Industrial Research Institute, Kyushu, Saga (Japan)

    1996-10-28

    It is well known that the solubilization of coal can be accelerated by adding sulfur or hydrogen sulfide during direct liquefaction of difficult coals. From the studies of authors on the coal liquefaction under the conditions at rather low temperatures between 300 and 400{degree}C, liquefaction products with high quality can be obtained by suppressing the aromatization of naphthene rings, but it was a problem that the reaction rate is slow. For improving this point, results obtained by changing solvents have been reported. In this study, to accelerate the liquefaction reaction, Illinois No.6 coal was liquefied in tetralin at temperature range from 300 to 400{degree}C by adding a given amount of sulfur or hydrogen sulfide at the initial stage of liquefaction. The addition of sulfur or hydrogen sulfide provided an acceleration effect of liquefaction reaction at temperature range between 300 and 400{degree}C. The addition of sulfur or hydrogen sulfide at 400{degree}C increased the oil products. At 370 and 400{degree}C, the liquid yield by adding sulfur was slightly higher than that by adding hydrogen sulfide, unexpectedly. The effects of sulfur and hydrogen sulfide were reversed when increasing the hydrogen pressure. 5 figs., 1 tab.

  15. Earthquake-induced liquefaction in Ferland, Quebec

    International Nuclear Information System (INIS)

    Tuttle, M.; Seeber, L.

    1991-02-01

    Detailed geological investigations are under way at a number of liquefaction sites in the Ferland-Boilleau valley, Quebec, where sand boils, ground cracks and liquefaction-related damages to homes were documented immediately following the Ms=6.0, Mblg=6.5 Saguenay earthquake of November 25, 1988. To date, results obtained from these subsurface investigations of sand boils at two sites in Ferland, located about 26 km from the epicentre, indicate that: the Saguenay earthquake induced liquefaction in late-Pleistocene and Holocene sediments which was recorded as sand dikes, sills and vents in near-surface sediments and soils; earthquake-induced liquefaction and ground failure have occurred in this area at least three times in the past 10,000 years; and, the size and morphology of liquefaction features and the liquefaction susceptibility of source layers of the features may be indicative of the intensity of ground shaking. These preliminary results are very promising and suggest that with continued research liquefaction features will become a useful tool in glaciated terrains, such as northeastern North America, for determining not only the timing and location but also the size of past earthquakes

  16. Liquefaction of uranium tailings

    International Nuclear Information System (INIS)

    1992-02-01

    Numerical methods for assessing the liquefaction potential of soils are reviewed with a view to their application to uranium tailings. The method can be divided into two categories: total stress analysis, where changes in pore pressure are not considered in the soil model, and effective stress analysis, where changes in pore pressure are included in the soil model. Effective stress analysis is more realistic, but few computer programs exist for such analysis in two or three dimensions. A simple linearized, two-dimensional, finite element effective stress analysis which incorporates volumetric compaction due to shear motion is described and implemented. The new program is applied to the assessment of liquefaction potential of tailings in the Quirke Mine tailings area near Elliot Lake, Ontario. The results are compared with those of a total stress analysis. Both analyses indicate liquefaction would occur if a magnitude 6.0 earthquake were to occur near the area. However, the extent of liquefaction predicted by the effective stress analysis is much less than that predicted by the total stress analysis. The results of both methods are sensitive to assumed material properties and to the method used to determine the cyclic shear strength of the tailings. Further analysis, incorporating more in situ and/or laboratory data, is recommended before conclusions can be made concerning the dynamic stability of these tailings

  17. A preliminary analysis of floating production storage and offloading facilities with gas liquefaction processes

    DEFF Research Database (Denmark)

    Nguyen, Tuong-Van; Carranza-Sánchez, Yamid Alberto; Junior, Silvio de Oliveira

    2016-01-01

    Floating, production, storage and offloading (FPSO) plants are facilities used in upstream petroleum processing. They have gained interest because they are more flexible than conventional plants and can be used for producing oil and gas in deep-water fields. In general, gas export is challenging...... because of the lack of infrastructure in remote locations. The present work investigates the possibility of integrating liquefaction processes on such facilities, considering two mixed-refrigerant and two expansion-based processes suitable for offshore applications. Two FPSO configurations are considered...... in this work, and they were suggested by Brazilian operators for fields processing natural gas with moderate to high content of carbon dioxide. The performance of the combined systems is analysed by conducting energy and exergy analyses. The integration of gas liquefaction results in greater power consumption...

  18. A novel vortex tube-based N2-expander liquefaction process for enhancing the energy efficiency of natural gas liquefaction

    Directory of Open Access Journals (Sweden)

    Qyyum Muhammad Abdul

    2017-01-01

    Full Text Available This research work unfolds a simple, safe, and environment-friendly energy efficient novel vortex tube-based natural gas liquefaction process (LNG. A vortex tube was introduced to the popular N2-expander liquefaction process to enhance the liquefaction efficiency. The process structure and condition were modified and optimized to take a potential advantage of the vortex tube on the natural gas liquefaction cycle. Two commercial simulators ANSYS® and Aspen HYSYS® were used to investigate the application of vortex tube in the refrigeration cycle of LNG process. The Computational fluid dynamics (CFD model was used to simulate the vortex tube with nitrogen (N2 as a working fluid. Subsequently, the results of the CFD model were embedded in the Aspen HYSYS® to validate the proposed LNG liquefaction process. The proposed natural gas liquefaction process was optimized using the knowledge-based optimization (KBO approach. The overall energy consumption was chosen as an objective function for optimization. The performance of the proposed liquefaction process was compared with the conventional N2-expander liquefaction process. The vortex tube-based LNG process showed a significant improvement of energy efficiency by 20% in comparison with the conventional N2-expander liquefaction process. This high energy efficiency was mainly due to the isentropic expansion of the vortex tube. It turned out that the high energy efficiency of vortex tube-based process is totally dependent on the refrigerant cold fraction, operating conditions as well as refrigerant cycle configurations.

  19. A novel vortex tube-based N2-expander liquefaction process for enhancing the energy efficiency of natural gas liquefaction

    Science.gov (United States)

    Qyyum, Muhammad Abdul; Wei, Feng; Hussain, Arif; Ali, Wahid; Sehee, Oh; Lee, Moonyong

    2017-11-01

    This research work unfolds a simple, safe, and environment-friendly energy efficient novel vortex tube-based natural gas liquefaction process (LNG). A vortex tube was introduced to the popular N2-expander liquefaction process to enhance the liquefaction efficiency. The process structure and condition were modified and optimized to take a potential advantage of the vortex tube on the natural gas liquefaction cycle. Two commercial simulators ANSYS® and Aspen HYSYS® were used to investigate the application of vortex tube in the refrigeration cycle of LNG process. The Computational fluid dynamics (CFD) model was used to simulate the vortex tube with nitrogen (N2) as a working fluid. Subsequently, the results of the CFD model were embedded in the Aspen HYSYS® to validate the proposed LNG liquefaction process. The proposed natural gas liquefaction process was optimized using the knowledge-based optimization (KBO) approach. The overall energy consumption was chosen as an objective function for optimization. The performance of the proposed liquefaction process was compared with the conventional N2-expander liquefaction process. The vortex tube-based LNG process showed a significant improvement of energy efficiency by 20% in comparison with the conventional N2-expander liquefaction process. This high energy efficiency was mainly due to the isentropic expansion of the vortex tube. It turned out that the high energy efficiency of vortex tube-based process is totally dependent on the refrigerant cold fraction, operating conditions as well as refrigerant cycle configurations.

  20. U.S. DOE indirect coal liquefaction program: An overview

    Energy Technology Data Exchange (ETDEWEB)

    Shen, J.; Schmetz, E.; Winslow, J.; Tischer, R. [Dept. of Energy, Germantown, MD (United States); Srivastava, R.

    1997-12-31

    Coal is the most abundant domestic energy resource in the United States. The Fossil Energy Organization within the US Department of Energy (DOE) has been supporting a coal liquefaction program to develop improved technologies to convert coal to clean and cost-effective liquid fuels to complement the dwindling supply of domestic petroleum crude. The goal of this program is to produce coal liquids that are competitive with crude at $20 to $25 per barrel. Indirect and direct liquefaction routes are the two technologies being pursued under the DOE coal liquefaction program. This paper will give an overview of the DOE indirect liquefaction program. More detailed discussions will be given to the F-T diesel and DME fuels which have shown great promises as clean burning alternative diesel fuels. The authors also will briefly discuss the economics of indirect liquefaction and the hurdles and opportunities for the early commercial deployment of these technologies. Discussions will be preceded by two brief reviews on the liquid versus gas phase reactors and the natural gas versus coal based indirect liquefaction.

  1. Modelling landslide liquefaction, mobility bifurcation and the dynamics of the 2014 Oso disaster

    Science.gov (United States)

    Iverson, Richard M.; George, David L.

    2016-01-01

    Some landslides move slowly or intermittently downslope, but others liquefy during the early stages of motion, leading to runaway acceleration and high-speed runout across low-relief terrain. Mechanisms responsible for this disparate behaviour are represented in a two-phase, depth-integrated, landslide dynamics model that melds principles from soil mechanics, granular mechanics and fluid mechanics. The model assumes that gradually increasing pore-water pressure causes slope failure to nucleate at the weakest point on a basal slip surface in a statically balanced mass. Failure then spreads to adjacent regions as a result of momentum exchange. Liquefaction is contingent on pore-pressure feedback that depends on the initial soil state. The importance of this feedback is illustrated by using the model to study the dynamics of a disastrous landslide that occurred near Oso, Washington, USA, on 22 March 2014. Alternative simulations of the event reveal the pronounced effects of a landslide mobility bifurcation that occurs if the initial void ratio of water-saturated soil equals the lithostatic, critical-state void ratio. They also show that the tendency for bifurcation increases as the soil permeability decreases. The bifurcation implies that it can be difficult to discriminate conditions that favour slow landsliding from those that favour liquefaction and long runout.

  2. Renewable chemical feedstocks from integrated liquefaction processing of lingocellulosic materials using microwave energy

    Science.gov (United States)

    Junming Xu; Jianchun Jiang; Chung-Yun Hse; Todd F. Shupe

    2012-01-01

    The objective of this investigation was to find a simple method for the production of phenolic rich products and sugar derivatives (biopolyols) via separation of liquefied lingocellulosic materials. Liquefaction of lignocellulosic materials was conducted in methanol at 180 °C for 15 min with the conversion of raw materials at about 75%. After liquefaction, the...

  3. Improvements on mapping soil liquefaction at a regional scale

    Science.gov (United States)

    Zhu, Jing

    Earthquake induced soil liquefaction is an important secondary hazard during earthquakes and can lead to significant damage to infrastructure. Mapping liquefaction hazard is important in both planning for earthquake events and guiding relief efforts by positioning resources once the events have occurred. This dissertation addresses two aspects of liquefaction hazard mapping at a regional scale including 1) predictive liquefaction hazard mapping and 2) post-liquefaction cataloging. First, current predictive hazard liquefaction mapping relies on detailed geologic maps and geotechnical data, which are not always available in at-risk regions. This dissertation improves the predictive liquefaction hazard mapping by the development and validation of geospatial liquefaction models (Chapter 2 and 3) that predict liquefaction extent and are appropriate for global application. The geospatial liquefaction models are developed using logistic regression from a liquefaction database consisting of the data from 27 earthquake events from six countries. The model that performs best over the entire dataset includes peak ground velocity (PGV), VS30, distance to river, distance to coast, and precipitation. The model that performs best over the noncoastal dataset includes PGV, VS30, water table depth, distance to water body, and precipitation. Second, post-earthquake liquefaction cataloging historically relies on field investigation that is often limited by time and expense, and therefore results in limited and incomplete liquefaction inventories. This dissertation improves the post-earthquake cataloging by the development and validation of a remote sensing-based method that can be quickly applied over a broad region after an earthquake and provide a detailed map of liquefaction surface effects (Chapter 4). Our method uses the optical satellite images before and after an earthquake event from the WorldView-2 satellite with 2 m spatial resolution and eight spectral bands. Our method

  4. Plasma electrolytic liquefaction of cellulosic biomass

    Science.gov (United States)

    Dingliang, TANG; Xianhui, ZHANG; Si-ze, YANG

    2018-04-01

    In this paper, the rapid liquefaction of a corncob was achieved by plasma electrolysis, providing a new method for cellulosic biomass liquefaction. The liquefaction rate of the corncob was 95% after 5 min with polyethylene glycol and glycerol as the liquefying agent. The experiments not only showed that H+ ions catalyzed the liquefaction of the corncob, but also that using accelerated H+ ions, which were accelerated by an electric field, could effectively improve the liquefaction efficiency. There was an obvious discharge phenomenon, in which the generated radicals efficiently heated the solution and liquefied the biomass, in the process of plasma electrolytic liquefaction. Finally, the optimum parameters of the corncob liquefaction were obtained by experimentation, and the liquefaction products were analyzed.

  5. Catalytic multi-stage liquefaction (CMSL)

    Energy Technology Data Exchange (ETDEWEB)

    Comolli, A.G.; Ganguli, P.; Karolkiewicz, W.F.; Lee, T.L.K.; Pradhan, V.R.; Popper, G.; Smith, T.; Stalzer, R.H.

    1996-11-01

    Reported herein are the details and the results of laboratory and bench scale experiments that were conducted at Hydrocarbon Technologies, Inc. under DOE Contract No. DE-AC22-93PC92147 during the period of October 1, 1992, to December 31, 1995. The program results described herein build on the previous technology base and investigating additional methods to improve the economics of producing transportation fuels from coal. This included purely physical parameters, coal treatment and variation in solvent to coal ratio, the use of syngas to replace part of the hydrogen as the reducing gas, the use of dispersed catalyst in addition to and replacing the supported catalyst, and the co-processing of coal with plastic waste material. The overall objective of this program is to produce liquid fuels from direct coal liquefaction at a cost that is competitive with conventional fuels. The report includes the results of an economic assessment of the various process strategies that were evaluated during this program. A summary of the technical/economic evaluations is given in Volume I, Section II of this report. The experimental details of the eleven run of the program are given in Volume I, Section III and Volume II of this report. The details of the technical evaluations are given in the Volume III of the report.

  6. Direct catalytic hydrothermal liquefaction of spirulina to biofuels with hydrogen

    Science.gov (United States)

    Zeng, Qin; Liao, Hansheng; Zhou, Shiqin; Li, Qiuping; Wang, Lu; Yu, Zhihao; Jing, Li

    2018-01-01

    We report herein on acquiring biofuels from direct catalytic hydrothermal liquefaction of spirulina. The component of bio-oil from direct catalytic hydrothermal liquefaction was similar to that from two independent processes (including liquefaction and upgrading of biocrude). However, one step process has higher carbon recovery, due to the less loss of carbons. It was demonstrated that the yield and HHV of bio-oil from direct catalytic algae with hydrothermal condition is higher than that from two independent processes.

  7. Basic studies on coal liquefaction reaction, reforming and utilization of liquefaction products

    Energy Technology Data Exchange (ETDEWEB)

    Shiraishi, M. (National Institute for Resources and Environment, Tsukuba (Japan))

    1993-09-01

    This report describes the achievement of research and development of coal liquefaction technologies in the Sunshine Project for FY 1992, regarding the coal liquefaction reaction, reforming and utilization of liquefaction products. For the fundamental study on coal liquefaction reaction, were investigated effect of asphaltene in petroleum residue on coprocessing, pretreatment effect in coprocessing of Taiheiyo coal and tarsand bitumen using oil soluble catalyst, solubilization and liquefaction of Taiheiyo coal at mild conditions with the aid of super acid, and flash hydropyrolysis of finely pulverized swollen coal under high hydrogen pressure. On the other hand, for the study on hydrotreatment of coal derived liquid, were investigated catalytic hydroprocessing of Wandoan coal liquids, production of gasoline from coal liquids by fluid catalytic cracking, solvent extraction of phenolic compounds from coal liquids, and separation of hetero compounds in coal liquid by means of high pressure crystallization. Further progress in these studies has been confirmed. 9 figs., 6 tabs.

  8. Coal liquefaction process streams characterization and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, G.A.; Brandes, S.D.; Winschel, R.A.; Burke, F.P.

    1992-03-01

    CONSOL R D is conducting a three-year program to characterize process and product streams from direct coal liquefaction process development projects. The program objectives are two-fold: (1) to obtain and provide appropriate samples of coal liquids for the evaluation of analytical methodology, and (2) to support ongoing DOE-sponsored coal liquefaction process development efforts. The two broad objectives have considerable overlap and together serve to provide a bridge between process development and analytical chemistry.

  9. Report on the achievements in research and development of a coal liquefaction technology in the Sunshine Project in fiscal 1981. Development of a solvolysis liquefaction plant (development of a 1 t/d experimental plant and research on solvolysis liquefaction process); Sekitan ekika gijutsu no kenkyu kaihatsu, solvolysis ekika plant no kaihatsu seika hokokusho. 1t/nichi jikken plant no kaihatsu (solvolysis ekika process no kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-03-01

    This paper describes the achievements in the Sunshine Project in fiscal 1981 in development of a solvolysis liquefaction plant. The solvolysis process is characterized by performing the first stage reaction (liquefaction) in a short time by using hydrogenated heavy solvent produced spontaneously in the process. This short-time liquefaction reaction was carried out continuously by using a 1-t/d experimental plant, and a prospect was obtained on smooth operation and realization of the device. A test using a testing device allowing the temperature to rise within several minutes was performed on the effectiveness of a hydrogenated coal based heavy solvent (fractions of a hydrogenated heavy anthracene as a model) as a study on the first stage reaction. Partially hydrogenated materials of polycyclic condensed aromatics in the heavy solvent is largely involved in the initial reaction. In the solid-liquid separation, solids and heavy fractions are selected and removed from the first stage reaction products, and the light fraction is supplied into the second stage reaction (hydrogenation). The solvent deliming process was tested by using a batch type solid-liquid separator, whose effectiveness was verified. Studies were performed by using Australian sub-bituminous coal on operation of a continuous operation device consisted of systems for the first stage reaction (liquefaction), solid-liquid separation, second stage reaction (hydrogenation), and solvent circulation. (NEDO)

  10. Assessment of liquefaction-induced hazards using Bayesian networks based on standard penetration test data

    Science.gov (United States)

    Tang, Xiao-Wei; Bai, Xu; Hu, Ji-Lei; Qiu, Jiang-Nan

    2018-05-01

    Liquefaction-induced hazards such as sand boils, ground cracks, settlement, and lateral spreading are responsible for considerable damage to engineering structures during major earthquakes. Presently, there is no effective empirical approach that can assess different liquefaction-induced hazards in one model. This is because of the uncertainties and complexity of the factors related to seismic liquefaction and liquefaction-induced hazards. In this study, Bayesian networks (BNs) are used to integrate multiple factors related to seismic liquefaction, sand boils, ground cracks, settlement, and lateral spreading into a model based on standard penetration test data. The constructed BN model can assess four different liquefaction-induced hazards together. In a case study, the BN method outperforms an artificial neural network and Ishihara and Yoshimine's simplified method in terms of accuracy, Brier score, recall, precision, and area under the curve (AUC) of the receiver operating characteristic (ROC). This demonstrates that the BN method is a good alternative tool for the risk assessment of liquefaction-induced hazards. Furthermore, the performance of the BN model in estimating liquefaction-induced hazards in Japan's 2011 Tōhoku earthquake confirms its correctness and reliability compared with the liquefaction potential index approach. The proposed BN model can also predict whether the soil becomes liquefied after an earthquake and can deduce the chain reaction process of liquefaction-induced hazards and perform backward reasoning. The assessment results from the proposed model provide informative guidelines for decision-makers to detect the damage state of a field following liquefaction.

  11. Comparison of oxygen liquefaction methods for use on the Martian surface

    Science.gov (United States)

    Johnson, W. L.; Hauser, D. M.; Plachta, D. W.; Wang, X.-Y. J.; Banker, B. F.; Desai, P. S.; Stephens, J. R.; Swanger, A. M.

    2018-03-01

    In order to use oxygen that is produced on the surface of Mars from In-Situ production processes in a chemical propulsion system, the oxygen must first be converted from vapor phase to liquid phase and then stored within the propellant tanks of the propulsions system. There are multiple ways that this can be accomplished, from simply attaching a liquefaction system onto the propellant tanks to carrying separate tanks for liquefaction and storage of the propellant and loading just prior to launch (the way that traditional rocket launches occur on Earth). A study was done into these various methods by which the oxygen (and methane) could be liquefied and stored on the Martian surface. Five different architectures or cycles were considered: Tube-on-Tank (also known as Broad Area Cooling or Distributed Refrigeration), Tube-in-Tank (also known as Integrated Refrigeration and Storage), a modified Linde open liquefaction/refrigeration cycle, the direct mounting of a pulse tube cryocooler onto the tank, and an in-line liquefier at ambient pressure. Models of each architecture were developed to give insight into the performance and losses of each of the options. The results were then compared across eight categories: Mass, Power (both input and heat rejection), Operability, Cost, Manufacturability, Reliability, Volume-ility, and Scalability. The result was that Tube-on-Tank and Tube-in-Tank architectures were the most attractive solutions, with NASA's engineering management choosing to pursue tube on tank development rather than further differentiate the two. As a result NASA is focusing its Martian surface liquefaction activities and technology development on Tube-on-Tank liquefaction cycles.

  12. Residual Liquefaction under Standing Waves

    DEFF Research Database (Denmark)

    Kirca, V.S. Ozgur; Sumer, B. Mutlu; Fredsøe, Jørgen

    2012-01-01

    This paper summarizes the results of an experimental study which deals with the residual liquefaction of seabed under standing waves. It is shown that the seabed liquefaction under standing waves, although qualitatively similar, exhibits features different from that caused by progressive waves....... The experimental results show that the buildup of pore-water pressure and the resulting liquefaction first starts at the nodal section and spreads towards the antinodal section. The number of waves to cause liquefaction at the nodal section appears to be equal to that experienced in progressive waves for the same...

  13. Hydrothermal liquefaction of biomass

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Rudolf, Andreas

    2011-01-01

    This article reviews the hydrothermal liquefaction of biomass with the aim of describing the current status of the technology. Hydrothermal liquefaction is a medium-temperature, high-pressure thermochemical process, which produces a liquid product, often called bio-oil or bi-crude. During...... the hydrothermal liquefaction process, the macromolecules of the biomass are first hydrolyzed and/or degraded into smaller molecules. Many of the produced molecules are unstable and reactive and can recombine into larger ones. During this process, a substantial part of the oxygen in the biomass is removed...... by dehydration or decarboxylation. The chemical properties of bio-oil are highly dependent of the biomass substrate composition. Biomass constitutes of various components such as protein; carbohydrates, lignin and fat, and each of them produce distinct spectra of compounds during hydrothermal liquefaction...

  14. Mineral catalysis of oil producing reactions in coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Shridharani, K.G.

    1983-01-01

    This work was concerned primarily with the development of a relatively inexpensive, readily available, high activity catalyst that can be used as a disposable catalyst in coal liquefaction processes. For a fair evaluation of the developmental mineral catalyst (presulfided iron oxide), it was necessary to determine at different stages of this work, whether catalyst inhibition, deactivation or activity was the limiting factor in coal liquefaction catalysis. First, different routes were explored to prepare a high hydrogenation activity, iron-based catalyst. Naphthalene hydrogenation was used as a model reaction to rate the hydrogenation activities of different additives. Presulfiding of iron oxide with H/sub 2/S, under controlled conditions, rendered the highest hydrogenation activity mineral catalyst, which had a hydrogenation activity even greater than that of commercial CoMo/Al/sub 2/O/sub 3/ catalyst sulfided with creosote oil and hydrogen. Sulfiding of CoMo/Al/sub 2/O/sub 3/ catalyst with H/sub 2/S remarkably improved its initial hydrogenation activity. Second, the catalyst inhibition and deactivation during liquefaction were studied. Liquefaction-process solvents contain a number of compounds that can either deactivate or inhibit the hydrogenation activity of a catalyst. Finally, the hydrocracking activity of the presulfided iron oxide catalyst was compared with that of commercial catalysts, CoMo/Al/sub 2/O/sub 3/ and low alumina FCC catalyst.

  15. Audiovisual integration in speech perception: a multi-stage process

    DEFF Research Database (Denmark)

    Eskelund, Kasper; Tuomainen, Jyrki; Andersen, Tobias

    2011-01-01

    investigate whether the integration of auditory and visual speech observed in these two audiovisual integration effects are specific traits of speech perception. We further ask whether audiovisual integration is undertaken in a single processing stage or multiple processing stages....

  16. Cooperative research in coal liquefaction infratechnology and generic technology development: Final report, October 1, 1985 to December 31, 1986

    Energy Technology Data Exchange (ETDEWEB)

    Sendlein, L.V.A.

    1987-06-29

    During the first year of its research program, the Consortium for Fossil Fuel Liquefaction Science has made significant progress in many areas of coal liquefaction and coal structure research. Research topics for which substantial progress has been made include integrated coal structure and liquefaction studies, investigation of differential liquefaction processes, development and application of sophisticated techniques for structural analysis, computer analysis of multivariate data, biodesulfurization of coal, catalysis studies, co-processing of coal and crude oil, coal dissolution and extraction processes, coal depolymerization, determination of the liquefaction characteristics of many US coals for use in a liquefaction database, and completion of a retrospective technology assessment for direct coal liquefaction. These and related topics are discussed in considerably more detail in the remainder of this report. Individual projects are processed separately for the data base.

  17. Status of health and environmental research relative to direct coal liquefaction: 1976 to the present

    Energy Technology Data Exchange (ETDEWEB)

    Gray, R.H.; Cowser, K.E. (eds.)

    1982-06-01

    This document describes the status of health and environmental research efforts, supported by the US Department of Energy (DOE), to assist in the development of environmentally acceptable coal liquefaction processes. Four major direct coal liquefaction processes are currently in (or have been investigated at) the pilot plant stage of development. Two solvent refined coal processes (SRC-I and -II), H-coal (a catalytic liquefaction process) and Exxon donor solvent (EDS). The Pacific Northwest Laboratory was assigned responsibility for evaluating SRC process materials and prepared comprehensive health and environmental effects research program plans for SRC-I and -II. A similar program plan was prepared for H-coal process materials by the Oak Ridge National Laboratory. A program has been developed for EDS process materials by Exxon Research and Engineering Co. The program includes short-term screening of coal-derived materials for potential health and ecological effects. Longer-term assays are used to evaluate materials considered most representative of potential commercial practice and with greatest potential for human exposure or release to the environment. Effects of process modification, control technologies and changing operational conditions on potential health and ecological effects are also being evaluated. These assessments are being conducted to assist in formulating cost-effective environmental research programs and to estimate health and environmental risks associated with a large-scale coal liquefaction industry. Significant results of DOE's health and environmental research efforts relative to coal liquefaction include the following: chemical characterization, health effects, ecological fate and effects, amelioration and risk assessment.

  18. Liquefaction macrophenomena in the great Wenchuan earthquake

    Science.gov (United States)

    Chen, Longwei; Yuan, Xiaoming; Cao, Zhenzhong; Hou, Longqing; Sun, Rui; Dong, Lin; Wang, Weiming; Meng, Fanchao; Chen, Hongjuan

    2009-06-01

    On May 12, 2008 at 14:28, a catastrophic magnitude M s 8.0 earthquake struck the Sichuan Province of China. The epicenter was located at Wenchuan (31.00°N, 103.40°E). Liquefaction macrophenomena and corresponding destruction was observed throughout a vast area of 500 km long and 200 km wide following the earthquake. This paper illustrates the geographic distribution of the liquefaction and the relationship between liquefaction behavior and seismic intensity, and summarizes the liquefaction macrophenomena, including sandboils and waterspouts, ground subsidence, ground fissures etc., and relevant liquefaction features. A brief summary of the structural damage caused by liquefaction is presented and discussed. Based on comparisons with liquefaction phenomena observed in the 1976 Tangshan and 1975 Haicheng earthquakes, preliminary analyses were performed, which revealed some new features of liquefaction behavior and associated issues arising from this event. The site investigation indicated that the spatial non-uniformity of liquefaction distribution was obvious and most of the liquefied sites were located in regions of seismic intensity VIII. However, liquefaction phenomena at ten different sites in regions of seismic intensity VI were also observed for the first time in China mainland. Sandboils and waterspouts ranged from centimeters to tens of meters, with most between 1 m to 3 m. Dramatically high water/sand ejections, e.g., more than 10 m, were observed at four different sites. The sand ejections included silty sand, fine sand, medium sand, course sand and gravel, but the ejected sand amount was less than that in the 1976 Tangshan earthquake. Possible liquefaction of natural gravel soils was observed for the first time in China mainland.

  19. Advancing early detection of autism spectrum disorder by applying an integrated two-stage screening approach

    NARCIS (Netherlands)

    Oosterling, Iris J.; Wensing, Michel; Swinkels, Sophie H.; van der Gaag, Rutger Jan; Visser, Janne C.; Woudenberg, Tim; Minderaa, Ruud; Steenhuis, Mark-Peter; Buitelaar, Jan K.

    Background: Few field trials exist on the impact of implementing guidelines for the early detection of autism spectrum disorders (ASD). The aims of the present study were to develop and evaluate a clinically relevant integrated early detection programme based on the two-stage screening approach of

  20. Advanced direct liquefaction concepts for PETC generic units. Final report, Phase I

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The Advanced Concepts for Direct Coal Liquefaction program was initiated by the Department of Energy in 1991 to develop technologies that could significantly reduce the cost of producing liquid fuels by the direct liquefaction of coal. The advanced 2-stage liquefaction technology that was developed at Wilsonville over the past 10 years has contributed significantly toward decreasing the cost of producing liquids from coal to about $33/bbl. It remains, however, the objective of DOE to further reduce this cost to a level more competitive with petroleum based products. This project, among others, was initiated to investigate various alternative approaches to develop technologies that might ultimately lead to a 25 % reduction in cost of product. In this project a number of novel concepts were investigated, either individually or in a coupled configuration that had the potential to contribute toward meeting the DOE goal. The concepts included mature technologies or ones closely related to them, such as coal cleaning by oil agglomeration, fluid coking and distillate hydrotreating and dewaxing. Other approaches that were either embryonic or less developed were chemical pretreatment of coal to remove oxygen, and dispersed catalyst development for application in the 2-stage liquefaction process. This report presents the results of this project. It is arranged in four sections which were prepared by participating organizations responsible for that phase of the project. A summary of the overall project and the principal results are given in this section. First, however, an overview of the process economics and the process concepts that were developed during the course of this program is presented.

  1. Efficient direct coal liquefaction of a premium brown coal catalyzed by cobalt-promoted fumed oxides

    Energy Technology Data Exchange (ETDEWEB)

    Trautmann, M.; Loewe, A.; Traa, Y. [Stuttgart Univ. (Germany). Inst. of Chemical Technology

    2013-11-01

    The search for alternatives in the fuel sector is an important technological challenge. An interim solution could be provided by direct coal liquefaction. Hydrogen economy and the lack of an efficient catalyst are the main obstacles for this process. We used a premium German brown coal with a high H/C molar ratio of 1.25 and nanostructured cobalt catalysts to improve the efficiency of direct coal liquefaction. We were able to recover and recycle the catalyst efficiently and reached good brown coal conversions and oil yields with single-stage coal liquefaction. The oil quality observed almost reached that of a conventional crude oil considering higher heating value (HHV), H/C molar ratio and aliphatic content. (orig.)

  2. Influence of catalytic activity and reaction conditions on the product distribution in coal liquefaction; Sekitan ekikayu no seiseibutsu bunpu ni taisuru shokubai kassei oyobi hanno joken no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Hasuo, H.; Sakanishi, K.; Mochida, I. [Kyushu University, Fukuoka (Japan). Institute of Advanced Material Study

    1996-10-28

    The NiMo sulfide supported on Ketjen Black (KB) was more effective and yielded lighter oil products containing light fractions with their boiling point below 300{degree}C during the two stage liquefaction combining low temperature and high temperature hydrogenation the conventional NiMo/alumina catalyst and FeS2 catalyst. Although the NiMo/alumina yielded increased oil products during the two stage liquefaction, the lighter oil fractions did not increase and the heavier fractions increased mainly. This suggests that the hydrogenation of aromatic rings and successive cleavage of the rings are necessary for producing the light oil, which is derived from the sufficient hydrogenation of aromatic rings using catalysts. For the two stage reaction with NiMo/KB catalyst, it was considered that sufficient hydrogen was directly transferred to coal molecules at the first stage of the low temperature reaction, which promoted the solubilization of coal and the successive hydrogenation at the high temperature reaction. Thus, high activity of the catalyst must be obtained. It is expected that further high quality distillates can be produced through the optimization of catalysts and solvents at the two stage reaction. 1 ref., 4 figs., 1 tab.

  3. Residual liquefaction of seabed under standing waves

    DEFF Research Database (Denmark)

    Kirca, V.S. Ozgur; Sumer, B. Mutlu; Fredsøe, Jørgen

    2013-01-01

    This paper presents the results of an experimental study of the seabed liquefaction beneath standing waves. Silt (with d50 =0.070mm) was used in the experiments. Two kinds of measurements were carried out: pore water pressure measurements and water surface elevation measurements. These measurements...... were synchronized with video recording of the liquefaction process from the side. The ranges of the various quantities in the experiments were wave height H= 5.9-12.0 cm, wave period T= 1.09s, and water depth h=30 cm. The experiments show that the seabed liquefaction under standing waves, although...... qualitatively similar, show features different from that caused by progressive waves. The pore water pressure builds up (or accumulated) in the areas around the node and subsequently spreads out toward the antinodes. The experimental results imply that this transport is caused by a diffusion mechanism...

  4. Exploratory Research on Novel Coal

    Energy Technology Data Exchange (ETDEWEB)

    Winschel, R.A.; Brandes, S.D.

    1998-05-01

    The report presents the findings of work performed under DOE Contract No. DE-AC22 -95PC95050, Task 3 - Flow Sheet Development. A novel direct coal liquefaction technology was investigated in a program being conducted by CONSOL Inc. with the University of Kentucky Center for Applied Energy Research and LDP Associates. The process concept explored consists of a first-stage coal dissolution step in which the coal is solubilized by hydride ion donation. In the second stage, the products are catalytically upgraded to refinery feedstocks. Integrated first-stage and solids-separation steps were used to prepare feedstocks for second-stage catalytic upgrading. An engineering and economic evaluation was conducted concurrently with experimental work throughout the program. Parameters were established for a low-cost, low-severity first-stage reaction system. A hydride ion reagent system was used to effect high coal conversions of Black Thunder Mine Wyoming subbituminous coal. An integrated first-stage and filtration step was successfully demonstrated and used to produce product filtrates with extremely low solids contents. High filtration rates previously measured off-line in Task 2 studies were obtained in the integrated system. Resid conversions of first-stage products in the second stage were found to be consistently greater than for conventional two-stage liquefaction resids. In Task 5, elementally balanced material balance data were derived from experimental results and an integrated liquefaction system balance was completed. The economic analysis indicates that the production of refined product (gasoline) via this novel direct liquefaction technology is higher than the cost associated with conventional two-stage liquefaction technologies. However, several approaches to reduce costs for the conceptual commercial plant were recommended. These approaches will be investigated in the next task (Task 4) of the program.

  5. Studies of initial stage in coal liquefaction. Effect of prethermal treatment condition with process solvent to increase oil yields; Ekika hanno no shoki katei ni kansuru kenkyu. Sekitan no maeshori joken to yozai koka

    Energy Technology Data Exchange (ETDEWEB)

    Shindo, T.; Komatsu, N.; Kishimoto, M.; Okui, T.; Kaneko, T.; Shimasaki, K. [Nippon Brown Coal Liquefaction Co. ltd., Tokyo (Japan)

    1996-10-28

    Process solvent was hydrogenated in the brown coal liquefaction, to investigate the influence of it on the prethermal treatment and liquefaction. Consequently, it was found that the n-hexane soluble (HS) yield was improved. In this study, capacity of hydrogen transfer from solvent during prethermal treatment and effects of catalyst were investigated. Since prethermal treatment in oil was effective for improving the oil yield in the presence of hydrogen/catalyst or high hydrogen-donor solvent, influence of hydrogen-donor performance of solvent or addition of catalyst on the hydrogenation behavior of coal and the characteristics of products during prethermal treatment were investigated in relation to successive liquefaction results. As a result, it was found that the increase of HS yield was due to the acceleration of conversion of THF-insoluble using high hydrogen-donor solvent and/or by adding catalyst. It was also found that the use of high hydrogen-donor solvent and highly active catalyst at the stage of prethermal treatment before the successive liquefaction was effective for improving the HS yield, i.e., liquefied oil yield. 2 refs., 5 figs., 1 tab.

  6. Effects of relative density and accumulated shear strain on post-liquefaction residual deformation

    Directory of Open Access Journals (Sweden)

    J. Kim

    2013-10-01

    Full Text Available The damage caused by liquefaction, which occurs following an earthquake, is usually because of settlement and lateral spreading. Generally, the evaluation of liquefaction has been centered on settlement, that is, residual volumetric strain. However, in actual soil, residual shear and residual volumetric deformations occur simultaneously after an earthquake. Therefore, the simultaneous evaluation of the two phenomena and the clarification of their relationship are likely to evaluate post-liquefaction soil behaviors more accurately. Hence, a quantitative evaluation of post-liquefaction damage will also be possible. In this study, the effects of relative density and accumulated shear strain on post-liquefaction residual deformations were reviewed through a series of lateral constrained-control hollow cylindrical torsion tests under undrained conditions. In order to identify the relationship between residual shear and residual volumetric strains, this study proposed a new test method that integrates monotonic loading after cyclic loading, and K0-drain after cyclic loading – in other words, the combination of cyclic loading, monotonic loading, and the K0 drain. In addition, a control that maintained the lateral constrained condition across all the processes of consolidation, cyclic loading, monotonic loading, and drainage was used to reproduce the anisotropy of in situ ground. This lateral constrain control was performed by controlling the axial strain, based on the assumption that under undrained conditions, axial and lateral strains occur simultaneously, and unless axial strain occurs, lateral strain does not occur. The test results confirmed that the recovery of effective stresses, which occur during monotonic loading and drainage after cyclic loading, respectively, result from mutually different structural restoration characteristics. In addition, in the ranges of 40–60% relative density and 50–100% accumulated shear strain, relative

  7. Report for fiscal 1994 by subcommittee on coal liquefaction basic technology; 1994 nendo ekika kiban gijutsu bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    This report covers the proceedings of subcommittee meetings. Using PDUs (process development unit), comparison is made between bituminous coal-derived oils (150t/d plant for the Indonesian coal) and brown coal-derived oils (50t/d plant for the Yallourn coal), product quality is improved by a 2-stage refining process, engines are tested, etc., all these demonstration and research efforts intended to win social recognition for coal liquefaction products. Among basic studies, there are the development of technologies for reforming coal-derived oils and for mixing them will petroleum, development of new catalysts for reforming, development of a technology for separating heterocompounds and the like, and the development of their applications. Furthermore, technologies are developed for environmentally friendly coal liquefaction, feasibility of coal liquefaction technology internationalization is deliberated, and technical researches and joint researches are conducted. At the second meeting of the subcommittee, achievements relative to the refining and applications of liquefaction products are presented, including the hydrorefining of naphtha, heating oil, and light oil; development of new catalysts; heterocompound separation technology; and the development of new applications. In relation with the development of environmentally friendly coal liquefaction technologies, studies are presented on liquefaction conditions and on the upgrading of basic technologies of liquefaction. Also referred to are the reports delivered at a meeting on liquefaction catalysts (January 1995). (NEDO)

  8. Behaviors of rice straw two-step liquefaction with sub/supercritical ethanol in carbon dioxide atmosphere.

    Science.gov (United States)

    Yang, Tianhua; Wang, Jian; Li, Bingshuo; Kai, Xingping; Xing, Wanli; Li, Rundong

    2018-06-01

    This study extended previous work investigating two-step liquefaction by supercritical ethanol of rice straw under CO 2 atmosphere at temperatures of 270-345 °C. Subcritical CO 2 -subcritical ethanol (SubCO 2 -SubEtOH) pretreatment decreased the content of lignin in the rice stalk from 22.94 to 21.43 wt%. The results showed that although oxygen-transfer reaction, transesterification, carbonylation, and other reactions may occur with the supercritical CO 2 -supercritical ethanol (ScCO 2 -ScEtOH) liquefaction reactions, transesterification was the main reaction. The "de-oxygen-transfer" reaction mainly comprised de-oxygenation and decarboxylation. For temperatures exceeding 320 °C, the bio-oil yield decreased because the effects of esters decreased. The residence time affected the H/C and O/C ratios to a minor extent. It was shown that the nucleophilic and hydrolytic functions of ethanol might be strengthened, generating higher amounts of ester, phenolic, acidic, and hydrocarbon derivatives in the bio-oil fraction. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Probabilistic liquefaction hazard analysis at liquefied sites of 1956 Dunaharaszti earthquake, in Hungary

    Science.gov (United States)

    Győri, Erzsébet; Gráczer, Zoltán; Tóth, László; Bán, Zoltán; Horváth, Tibor

    2017-04-01

    about 5 km from the southern boundary of Budapest. The quake caused serious damages in the epicentral area and in the southern districts of the capital. The epicentral area of the earthquake is located along the Danube River. Sand boils were observed in some locations that indicated the occurrence of liquefaction. Because their exact locations were recorded at the time of the earthquake, in situ geotechnical measurements (CPT and SPT) could be performed at two (Dunaharaszti and Taksony) sites. The different types of measurements enabled the probabilistic liquefaction hazard computations at the two studied sites. We have compared the return periods of liquefaction that were computed using different built-in simplified stress based methods.

  10. Cooperative research in coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Huffman, G.P.; Sendlein, L.V.A. (eds.)

    1991-05-28

    Significant progress was made in the May 1990--May 1991 contract period in three primary coal liquefaction research areas: catalysis, structure-reactivity studies, and novel liquefaction processes. A brief summary of the accomplishments in the past year in each of these areas is given.

  11. Machine learning modelling for predicting soil liquefaction susceptibility

    Directory of Open Access Journals (Sweden)

    P. Samui

    2011-01-01

    Full Text Available This study describes two machine learning techniques applied to predict liquefaction susceptibility of soil based on the standard penetration test (SPT data from the 1999 Chi-Chi, Taiwan earthquake. The first machine learning technique which uses Artificial Neural Network (ANN based on multi-layer perceptions (MLP that are trained with Levenberg-Marquardt backpropagation algorithm. The second machine learning technique uses the Support Vector machine (SVM that is firmly based on the theory of statistical learning theory, uses classification technique. ANN and SVM have been developed to predict liquefaction susceptibility using corrected SPT [(N160] and cyclic stress ratio (CSR. Further, an attempt has been made to simplify the models, requiring only the two parameters [(N160 and peck ground acceleration (amax/g], for the prediction of liquefaction susceptibility. The developed ANN and SVM models have also been applied to different case histories available globally. The paper also highlights the capability of the SVM over the ANN models.

  12. Studies on the catalysts for coal liquefaction. ; Kinetic discussion in initial stage of coal liquefaction. Sekitan ekikayo shokubai ni kansuru kenkyu. ; Sekitan ekika shoki dankai no sokudoronteki kosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Muraoka, T; Ikenaga, N; Oda, H; Yokokawa, C [Kansai University, Osaka (Japan). Faculty of Engineering

    1990-11-29

    Discussions were given on features of various kinds of coal liquefaction catalysts exhibited by them in hydrocracking of coal (Taiheiyo coal), and particularly on selectivity of the reaction in its initial stage. Four kinds of catalysts were tested: Adkins catalyst which is an oxide of copper and chromium, Fe2O3+S, Mo-TiO2 and MoS3-Al2O3. Three grams of coal and 0.3 gram each of the catalysts were charged into an autoclave reactor and experiment was conducted under an initial hydrogen pressure of 10 MPa, temperatures from 653 K to 693 K and for durations of 0 to 120 minutes to derive apparent reaction rate constants. The MoS3-Al2O3 catalyst has promoting the reaction apparently in the primary reaction at any temperature, while the other catalysts had the rate constants varied in the initial and the later stages. It was recognized that the temperature dependence of rate constants varies considerably according to the types of catalyst. Particularly the MoO3-TiO3 catalyst has small temperature dependence in the rate constants, and high molecular weight reducing power. 3 refs., 4 figs., 3 tabs.

  13. Helium refrigeration system for hydrogen liquefaction applications

    Science.gov (United States)

    Nair, J. Kumar, Sr.; Menon, RS; Goyal, M.; Ansari, NA; Chakravarty, A.; Joemon, V.

    2017-02-01

    Liquid hydrogen around 20 K is used as cold moderator for generating “cold neutron beam” in nuclear research reactors. A cryogenic helium refrigeration system is the core upon which such hydrogen liquefaction applications are built. A thermodynamic process based on reversed Brayton cycle with two stage expansion using high speed cryogenic turboexpanders (TEX) along with a pair of compact high effectiveness process heat exchangers (HX), is well suited for such applications. An existing helium refrigeration system, which had earlier demonstrated a refrigeration capacity of 470 W at around 20 K, is modified based on past operational experiences and newer application requirements. Modifications include addition of a new heat exchanger to simulate cryogenic process load and two other heat exchangers for controlling the temperatures of helium streams leading out to the application system. To incorporate these changes, cryogenic piping inside the cold box is suitably modified. This paper presents process simulation, sizing of new heat exchangers as well as fabrication aspects of the modified cryogenic process piping.

  14. Advances in Seabed Liquefaction and its Implications for Marine Structures

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu

    2013-01-01

    A review is presented of recent advances in seabed liquefaction and its implications for marine structures. The review is organized in seven sections: Residual liquefaction, including the sequence of liquefaction, mathematical modelling, centrifuge modelling and comparison with standard wave-flum......-flume results; Momentary liquefaction; Floatation of buried pipelines; Sinking of pipelines and marine objects; Liquefaction at gravity structures; Stability of rock berms in liquefied soils; and Impact of seismic-induced liquefaction....

  15. An unit cost adjusting heuristic algorithm for the integrated planning and scheduling of a two-stage supply chain

    Directory of Open Access Journals (Sweden)

    Jianhua Wang

    2014-10-01

    Full Text Available Purpose: The stable relationship of one-supplier-one-customer is replaced by a dynamic relationship of multi-supplier-multi-customer in current market gradually, and efficient scheduling techniques are important tools of the dynamic supply chain relationship establishing process. This paper studies the optimization of the integrated planning and scheduling problem of a two-stage supply chain with multiple manufacturers and multiple retailers to obtain a minimum supply chain operating cost, whose manufacturers have different production capacities, holding and producing cost rates, transportation costs to retailers.Design/methodology/approach: As a complex task allocation and scheduling problem, this paper sets up an INLP model for it and designs a Unit Cost Adjusting (UCA heuristic algorithm that adjust the suppliers’ supplying quantity according to their unit costs step by step to solve the model.Findings: Relying on the contrasting analysis between the UCA and the Lingo solvers for optimizing many numerical experiments, results show that the INLP model and the UCA algorithm can obtain its near optimal solution of the two-stage supply chain’s planning and scheduling problem within very short CPU time.Research limitations/implications: The proposed UCA heuristic can easily help managers to optimizing the two-stage supply chain scheduling problems which doesn’t include the delivery time and batch of orders. For two-stage supply chains are the most common form of actual commercial relationships, so to make some modification and study on the UCA heuristic should be able to optimize the integrated planning and scheduling problems of a supply chain with more reality constraints.Originality/value: This research proposes an innovative UCA heuristic for optimizing the integrated planning and scheduling problem of two-stage supply chains with the constraints of suppliers’ production capacity and the orders’ delivering time, and has a great

  16. Hydrothermal liquefaction of biomass

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Hoffmann, Jessica

    2014-01-01

    Biomass is one of the most abundant sources of renewable energy, and will be an important part of a more sustainable future energy system. In addition to direct combustion, there is growing attention on conversion of biomass into liquid en-ergy carriers. These conversion methods are divided...... into biochemical/biotechnical methods and thermochemical methods; such as direct combustion, pyrolysis, gasification, liquefaction etc. This chapter will focus on hydrothermal liquefaction, where high pressures and intermediate temperatures together with the presence of water are used to convert biomass...... into liquid biofuels, with the aim of describing the current status and development challenges of the technology. During the hydrothermal liquefaction process, the biomass macromolecules are first hydrolyzed and/or degraded into smaller molecules. Many of the produced molecules are unstable and reactive...

  17. Optimization of a Two Stage Pulse Tube Refrigerator for the Integrated Current Lead System

    Science.gov (United States)

    Maekawa, R.; Matsubara, Y.; Okada, A.; Takami, S.; Konno, M.; Tomioka, A.; Imayoshi, T.; Hayashi, H.; Mito, T.

    2008-03-01

    Implementation of a conventional current lead with a pulse tube refrigerator has been validated to be working as an Integrated Current Lead (ICL) system for the Superconducting Magnetic Energy Storage (SMES). Realization of the system is primarily accounted for the flexibility of a pulse tube refrigerator, which does not posses any mechanical piston and/or displacer. As for an ultimate version of the ICL system, a High Temperature Superconducting (HTS) lead links a superconducting coil with a conventional copper lead. To ensure the minimization of heat loads to the superconducting coil, a pulse tube refrigerator has been upgraded to have a second cooling stage. This arrangement reduces not only the heat loads to the superconducting coil but also the operating cost for a SMES system. A prototype two-stage pulse tube refrigerator, series connected arrangement, was designed and fabricated to satisfy the requirements for the ICL system. Operation of the first stage refrigerator is a four-valve mode, while the second stage utilizes a double inlet configuration to ensure its confined geometry. The paper discusses the optimization of second stage cooling to validate the conceptual design

  18. A preliminary study on the optimal configuration and operating range of a “microgrid scale” air liquefaction plant for Liquid Air Energy Storage

    International Nuclear Information System (INIS)

    Borri, E.; Tafone, A.; Romagnoli, A.; Comodi, G.

    2017-01-01

    Highlights: • A liquefaction cycle for a microgrid scale Liquid Air Energy Storage is proposed. • Different liquefaction cycles are compared by means of parametric analysis. • The optimal configuration proposed is a Kapitza cycle with two stage compression. • The specific consumption of the optimal configuration is around 700 kW h/t. • Specific consumption reduces to 532 kW h/t if a pressurized phase separator is used. - Abstract: Liquid Air Energy Storage systems represent a sustainable solution to store energy. Although a lot of interest is dedicated to large scale systems (up to 300 tons per day), a small-scale Liquid Air Energy Storage can be used as energy storage as part of a microgrid and/or an energy distribution network. However, when scaling down the size of the system, the round trip efficiency decreases due to the low performance of the liquefaction process. In this paper a preliminary study on the optimal configuration for a microgrid scale liquefaction cycle (10 tons per 12 h) for a Liquid Air Energy Storage application is proposed in order to minimize the specific consumption. The Linde, Claude and Kapitza cycles are modelled and compared by means of a parametric analysis carried out with the software Aspen HYSYS. The results show that the two stages compression Kapitza cycle operating at 40 bar represents an optimal solution in terms of performance and cycle configuration resulting in a specific consumption of about 700 kW h/t. The analysis also shows that the implementation of a pressurized phase separator leads to a reduction of the specific consumption as high as 21% (≈550 kW h/t).

  19. FY 1980 Report on results of Sunshine Project by Coal Group. Basic researches on coal liquefaction techniques by solvolysis; 1980 nendo sunshine keikaku sekitanhan hokokusho. Sekitan no solvolysis ekika gijutsu no kiso kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-07-01

    The basic experimental researches were carried out for coal liquefaction by solvolysis. The studied items include hydrogenation conditions for treating the primary liquefied products, asphalt, pitch and model solvents (e.g., anthracene oil) in the presence of a commercial catalyst, solvolysis conditions for finely divided, molten coal using a hydrogenation recycled solvent, hydrotreating solvents, analysis of solvolysis-liquefied products, and liquefaction capacity of fractionated solvents for finely divided, molten coal. The studied items for separation of minerals include settlement at high temperature of the solid residue from the first liquefaction stage, and changed coal particle size distribution as a result of the first-stage liquefaction reactions in the presence of a hydrogenation solvent. The experimental study results indicate that conversion of finely divided molten coal into asphaltenes and preasphaltenes is notably accelerated in the phase-II coal liquefaction process by solvolysis, when a hydrotreating solvent is used for the first stage solvolysis process. (NEDO)

  20. 57Fe NGR studies on three-stage hydroliquefaction of coals

    International Nuclear Information System (INIS)

    Jamond, M.; Bacaud, R.; Bussiere, P.; Charcosset, H.; Nickel-Pepin-Donat, B.

    1990-01-01

    Iron Moessbauer spectroscopy has been performed on liquefaction residues of two different French coals. In a three-stage liquefaction of high volatile bituminous coal (Freyming), without an added catalyst, the coal pyrite is not entirely converted into pyrrhotites, whereas in the presence of an added catalyst, coal pyrite is totally transformed into more dispersed pyrrhotites than those from the sample without an added catalyst; furthermore, the whole added catalyst precursor is reduced into pyrrhotites. In the case of liquefaction of subbituminous coal (Gardanne), full conversion of coal pyrite into pyrrhotites (even without an added catalyst) occurs. In addition, in the presence of the added catalyst, besides pyrrhotites, FeS is evidenced. When molybdenum-iron oxide is added as a catalyst precursor, no mixed Fe-Mo phase is detected. (orig.)

  1. Methods of natural gas liquefaction and natural gas liquefaction plants utilizing multiple and varying gas streams

    Science.gov (United States)

    Wilding, Bruce M; Turner, Terry D

    2014-12-02

    A method of natural gas liquefaction may include cooling a gaseous NG process stream to form a liquid NG process stream. The method may further include directing the first tail gas stream out of a plant at a first pressure and directing a second tail gas stream out of the plant at a second pressure. An additional method of natural gas liquefaction may include separating CO.sub.2 from a liquid NG process stream and processing the CO.sub.2 to provide a CO.sub.2 product stream. Another method of natural gas liquefaction may include combining a marginal gaseous NG process stream with a secondary substantially pure NG stream to provide an improved gaseous NG process stream. Additionally, a NG liquefaction plant may include a first tail gas outlet, and at least a second tail gas outlet, the at least a second tail gas outlet separate from the first tail gas outlet.

  2. Liquefaction resistance of calcareous sands

    International Nuclear Information System (INIS)

    Sandoval Vallejo, Eimar

    2012-01-01

    Calcareous sands are unique in terms of their origin, mineralogy, shape, fragility and intra particle porosity. This article presents results from an experimental program carried out to study the liquefaction resistance of a calcareous sand retrieved from Cabo Rojo at Puerto Rico. The experimental program included mineralogical characterization, index properties, and undrained cyclic triaxial tests on isotropically consolidated reconstituted samples. Due to the large variation in the calcareous sand properties, results are compared with previous researches carried out on other calcareous sands around the world. Results showed a wide range in the liquefaction resistance of the studied calcareous sands. Cabo Rojo sand experienced greater liquefaction resistance than most of the calcareous sands used for comparison. Important differences in the excess pore pressure generation characteristics were also found.

  3. Hydrothermal Liquefaction of Biomass

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.

    2010-12-10

    collaboration with Canada to investigate kelp (seaweed) as a biomass feedstock. The collaborative project includes process testing of the kelp in HydroThermal Liquefaction in the bench-scale unit at PNNL. HydroThermal Liquefaction at PNNL is performed in the hydrothermal processing bench-scale reactor system. Slurries of biomass are prepared in the laboratory from whole ground biomass materials. Both wet processing and dry processing mills can be used, but the wet milling to final slurry is accomplished in a stirred ball mill filled with angle-cut stainless steel shot. The PNNL HTL system, as shown in the figure, is a continuous-flow system including a 1-litre stirred tank preheater/reactor, which can be connected to a 1-litre tubular reactor. The product is filtered at high-pressure to remove mineral precipitate before it is collected in the two high-pressure collectors, which allow the liquid products to be collected batchwise and recovered alternately from the process flow. The filter can be intermittently back-flushed as needed during the run to maintain operation. By-product gas is vented out the wet test meter for volume measurement and samples are collected for gas chromatography compositional analysis. The bio-oil product is analyzed for elemental content in order to calculate mass and elemental balances around the experiments. Detailed chemical analysis is performed by gas chromatography-mass spectrometry and 13-C nuclear magnetic resonance is used to evaluate functional group types in the bio-oil. Sufficient product is produced to allow subsequent catalytic hydroprocessing to produce liquid hydrocarbon fuels. The product bio-oil from hydrothermal liquefaction is typically a more viscous product compared to fast pyrolysis bio-oil. There are several reasons for this difference. The HTL bio-oil contains a lower level of oxygen because of more extensive secondary reaction of the pyrolysis products. There are less amounts of the many light oxygenates derived from the

  4. Evaluation of soil liquefaction potential for level ground during earthquakes. A summary report

    International Nuclear Information System (INIS)

    Seed, H.B.; Arango, I.; Chan, C.K.

    1975-10-01

    The results of a three-year research program conducted to investigate the settlement and liquefaction of sands under multi-directional shaking are evaluated. The investigation indicated that the behavior of a saturated sand under cyclic loading conditions is a function of its geologic and seismic history and grain structure as well as its placement density. It is concluded that the resistance to liquefaction of a sand deposit can best be estimated by laboratory testing on undisturbed samples. It is shown that cyclic triaxial tests used in conjunction with appropriate correction factors to account for multi-directional shaking, simple shear loading conditions, and overconsolidation effects can provide valid data on cyclic loading characteristics. The concepts of ''limited strain potential'' and acceptable value of the factor of safety against initial liquefaction are introduced. Finally, the two basic methods for evaluating liquefaction potential and the effects of liquefaction are reviewed and updated with the information obtained through this research effort

  5. Survey on peripheral techniques of brown coal liquefaction techniques; Kattan ekika gijutsu ni kansuru shuhen gijutsu no chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-09-01

    Described herein are results of survey on brown coal liquefaction techniques and peripheral techniques, centered by COSTEAM process under development in USA, solubilization by alcohol and liquefaction and cracking with the aid of tetrahydroquinoline as the hydrogen donor under development in Japan, and low-temperature carbonization and new promising techniques. The COSTEAM process shows higher reaction rates, conversions and oil yields for brown coal liquefaction than the one using hydrogen gas. Some of the problems involved in this process high viscosity and oxygenated compound content of the product oil. The product oil is acceptable as fuel for power generating plants and can be produced at a moderate cost, but may be unsuitable as vehicle fuel. Coal liquefaction and solubilization processes are mainly represented by those which use hydrogen. The hydrogen cost, which is high, determines the product price. The processes which use alcohol or tetrahydroquinoline are still in the experimental stage. (NEDO)

  6. Studies of initial stage in coal liquefaction. Effect of decomposition of oxygen-functional groups on coal liquefaction; Ekika hanno no shoki katei ni kansuru kenkyu. 3. Gansanso kannoki no bunkai kyodo to ekika hanno eno eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Komeiji, A.; Kaneko, T.; Shimazaki, K. [Nippon Brown Coal Liquefaction Co. Ltd., Tokyo (Japan)

    1996-10-28

    Pretreatment of brown coal in oil was conducted using 1-methyl naphthalene or mixture of tetralin and 1-methyl naphthalene as solvent at temperatures ranging from 300 to 430{degree}C under nitrogen atmosphere. Effects of the solvent properties on the structural change of oxygen-functional groups (OFG) and coal liquefaction were investigated by means of quantitative analysis of OFG and solid state {sup 13}C-NMR measurement. When hydrogen transfer from solvent was insufficient, it was suggested that brown coal molecules loose their hydrogen to be aromatized. While, at lower temperatures ranging from 300 to 350{degree}C, hydrogen contained in brown coal molecules was consumed for the stabilization of pyrolytic radicals, and the deterioration of liquefaction was not observed. When hydrogen transfer from solvent was insufficient at higher temperatures above 400{degree}C in nitrogen atmosphere during pretreatment in oil, crosslinking like benzofuran type was formed by dehydration condensation of hydroxyl group in brown coal, to deteriorate the liquefaction, remarkably. The addition of donor solvent like tetralin decreased the formation of crosslinking like benzofuran type, which suppressed the deterioration of liquefaction. 8 refs., 5 figs.

  7. Mars Propellant Liquefaction Modeling in Thermal Desktop

    Science.gov (United States)

    Desai, Pooja; Hauser, Dan; Sutherlin, Steven

    2017-01-01

    NASAs current Mars architectures are assuming the production and storage of 23 tons of liquid oxygen on the surface of Mars over a duration of 500+ days. In order to do this in a mass efficient manner, an energy efficient refrigeration system will be required. Based on previous analysis NASA has decided to do all liquefaction in the propulsion vehicle storage tanks. In order to allow for transient Martian environmental effects, a propellant liquefaction and storage system for a Mars Ascent Vehicle (MAV) was modeled using Thermal Desktop. The model consisted of a propellant tank containing a broad area cooling loop heat exchanger integrated with a reverse turbo Brayton cryocooler. Cryocooler sizing and performance modeling was conducted using MAV diurnal heat loads and radiator rejection temperatures predicted from a previous thermal model of the MAV. A system was also sized and modeled using an alternative heat rejection system that relies on a forced convection heat exchanger. Cryocooler mass, input power, and heat rejection for both systems were estimated and compared against sizing based on non-transient sizing estimates.

  8. Development of an extruder-feeder biomass direct liquefaction process

    Energy Technology Data Exchange (ETDEWEB)

    White, D.H.; Wolf, D. (Arizona Univ., Tucson, AZ (United States). Dept. of Chemical Engineering)

    1991-10-01

    As an abundant, renewable, domestic energy resource, biomass could help the United States reduce its dependence on imported oil. Biomass is the only renewable energy technology capable of addressing the national need for liquid transportation fuels. Thus, there is an incentive to develop economic conversion processes for converting biomass, including wood, into liquid fuels. Through research sponsored by the US DOE's Biomass Thermochemical Conversion Program, the University of Arizona has developed a unique biomass direct liquefaction system. The system features a modified single-screw extruder capable of pumping solid slurries containing as high as 60 wt% wood flour in wood oil derived vacuum bottoms at pressures up to 3000 psi. The extruder-feeder has been integrated with a unique reactor by the University to form a system which offers potential for improving high pressure biomass direct liquefaction technology. The extruder-feeder acts simultaneously as both a feed preheater and a pumping device for injecting wood slurries into a high pressure reactor in the biomass liquefaction process. An experimental facility was constructed and following shakedown operations, wood crude oil was produced by mid-1985. By July 1988, a total of 57 experimental continuous biomass liquefaction runs were made using White Birch wood feedstock. Good operability was achieved at slurry feed rates up to 30 lb/hr, reactor pressures from 800 to 3000 psi and temperatures from 350{degree}C to 430{degree}C under conditions covering a range of carbon monoxide feed rates and sodium carbonate catalyst addition. Crude wood oils containing as little as 6--10 wt% residual oxygen were produced. 38 refs., 82 figs., 26 tabs.

  9. Whole Algae Hydrothermal Liquefaction Technology Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Biddy, M.; Davis, R.; Jones, S.

    2013-03-01

    This technology pathway case investigates the feasibility of using whole wet microalgae as a feedstock for conversion via hydrothermal liquefaction. Technical barriers and key research needs have been assessed in order for the hydrothermal liquefaction of microalgae to be competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks.

  10. Subtask 3.3 - Feasibility of Direct Coal Liquefaction in the Modern Economic Climate

    Energy Technology Data Exchange (ETDEWEB)

    Benjamin Oster; Joshua Strege; Marc Kurz; Anthony Snyder; Melanie Jensen

    2009-06-15

    Coal liquefaction provides an alternative to petroleum for the production of liquid hydrocarbon-based fuels. There are two main processes to liquefy coal: direct coal liquefaction (DCL) and indirect coal liquefaction (ICL). Because ICL has been demonstrated to a greater extent than DCL, ICL may be viewed as the lower-risk option when it comes to building a coal liquefaction facility. However, a closer look, based on conversion efficiencies and economics, is necessary to determine the optimal technology. This report summarizes historical DCL efforts in the United States, describes the technical challenges facing DCL, overviews Shenhua's current DCL project in China, provides a DCL conceptual cost estimate based on a literature review, and compares the carbon dioxide emissions from a DCL facility to those from an ICL facility.

  11. Secondary liquefaction in ethanol production

    DEFF Research Database (Denmark)

    2007-01-01

    The invention relates to a method of producing ethanol by fermentation, said method comprising a secondary liquefaction step in the presence of a themostable acid alpha-amylase or, a themostable maltogenic acid alpha-amylase.......The invention relates to a method of producing ethanol by fermentation, said method comprising a secondary liquefaction step in the presence of a themostable acid alpha-amylase or, a themostable maltogenic acid alpha-amylase....

  12. Liquefaction of lignohemicellulosic waste by processing with carbon monoxide and water

    Energy Technology Data Exchange (ETDEWEB)

    El-Saied, H

    1977-09-01

    The liquefaction of lignohemicellulosic waste by processing with carbon monoxide and water for 10 minutes at 250/sup 0/-440/sup 0/C and 40 to 70 atm initial pressure in a rocking autoclave produced benzene-soluble heavy oil in yields up to 80%. High conversion and yields were favored by high thermal stress, short reaction times, and sufficient hydrogen to prevent radical recombination in the critical liquefaction stages. The addition of sodium or calcium hydroxide, sodium carbonate, iron oxide, etc. in small amounts gave good oil yields under less severe conditions. Lignins from rice straw, bagasse, and other grasses gave higher yields than the woody lignin obtained from cotton stalks. In products obtained by liquefying black liquor lignohemicellulose from an Eyptian rice straw pulping plant, the hydrogen-carbon atomic ratio was 1.0 to 1.3:1.

  13. Development of continuous bench scale unit for direct liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Wang Lai [Korea Inst. of Energy and Resources, Daeduk (Korea, Republic of)

    1996-12-31

    Batch coal liquefaction experiments using tubing bombs and continuous experiments by cell liquefaction test facility were carried out. The main purpose was to maximize the coal liquefaction yields by improving the activity of coal dissolution catalysts which are oil soluble transition metal naphthenate and to supplement the incomplete research results. In the meantime, the study on the reaction characteristics of coal liquefaction and coal liquid upgrading catalyst upon sulfiding conditions and phosphorous addition have been conducted (author). 102 refs., 35 figs.

  14. Development of continuous bench scale unit for direct liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Wang Lai [Korea Inst. of Energy and Resources, Daeduk (Korea, Republic of)

    1995-12-31

    Batch coal liquefaction experiments using tubing bombs and continuous experiments by cell liquefaction test facility were carried out. The main purpose was to maximize the coal liquefaction yields by improving the activity of coal dissolution catalysts which are oil soluble transition metal naphthenate and to supplement the incomplete research results. In the meantime, the study on the reaction characteristics of coal liquefaction and coal liquid upgrading catalyst upon sulfiding conditions and phosphorous addition have been conducted (author). 102 refs., 35 figs.

  15. Retesting of liquefaction and nonliquefaction case histories from the 1976 Tangshan earthquake

    Science.gov (United States)

    Moss, R.E.S.; Kayen, R.E.; Tong, L.-Y.; Liu, S.-Y.; Cai, G.-J.; Wu, J.

    2011-01-01

    A field investigation was performed to retest liquefaction and nonliquefaction sites from the 1976 Tangshan earthquake in China. These sites were carefully investigated in 1978 and 1979 by using standard penetration test (SPT) and cone penetration test (CPT) equipment; however, the CPT measurements are obsolete because of the now nonstandard cone that was used at the time. In 2007, a modern cone was mobilized to retest 18 selected sites that are particularly important because of the intense ground shaking they sustained despite their high fines content and/or because the site did not liquefy. Of the sites reinvestigated and carefully reprocessed, 13 were considered accurate representative case histories. Two of the sites that were originally investigated for liquefaction have been reinvestigated for cyclic failure of fine-grained soil and removed from consideration for liquefaction triggering. The most important outcome of these field investigations was the collection of more accurate data for three nonliquefaction sites that experienced intense ground shaking. Data for these three case histories is now included in an area of the liquefaction triggering database that was poorly populated and will help constrain the upper bound of future liquefaction triggering curves. ?? 2011 American Society of Civil Engineers.

  16. Earthquake induced liquefaction hazard, probability and risk assessment in the city of Kolkata, India: its historical perspective and deterministic scenario

    Science.gov (United States)

    Nath, Sankar Kumar; Srivastava, Nishtha; Ghatak, Chitralekha; Adhikari, Manik Das; Ghosh, Ambarish; Sinha Ray, S. P.

    2018-01-01

    synthesized bedrock ground motion for both the 1897 and 1934 earthquakes on non-linear analysis of local site conditions through DEEPSOIL Geotechnical analysis package present surface level peak ground acceleration of the order of 0.05-0.14 g for the 1934 Bihar-Nepal earthquake while for the 1897 Shillong earthquake it is found to be in the range of 0.03-0.11 g. The factor of safety (FOS) against liquefaction, the probability of liquefaction ( P L), the liquefaction potential index (LPI), and the liquefaction risk index are estimated under the influence of these two earthquakes wherein the city is classified into severe (LPI > 15), high (5 65% comprising of coarse-grained sediments of sand, silty sand, and clayey silty sand in mostly the deltaic plain geomorphologic unit with 39.1% sites depicting severe liquefaction hazard with a median LPI of 28.3. A non-linear regression analysis on both the historical and deterministic liquefaction scenarios in P L versus LPI domain with ± 1 standard deviation confidence bound generated a cubic polynomial relationship between the two liquefaction hazard proxies. This study considered a bench mark for other cities in the country and elsewhere forms an integral part of the mega-seismic microzonation endeavors undertaken in all the earthquake-prone counties in the world.

  17. Technology for advanced liquefaction processes: Coal/waste coprocessing studies

    Energy Technology Data Exchange (ETDEWEB)

    Cugini, A.V.; Rothenberger, K.S.; Ciocco, M.V. [Pittsburgh Energy Technology Center, PA (United States)] [and others

    1995-12-31

    The efforts in this project are directed toward three areas: (1) novel catalyst (supported and unsupported) research and development, (2) study and optimization of major operating parameters (specifically pressure), and (3) coal/waste coprocessing. The novel catalyst research and development activity has involved testing supported catalysts, dispersed catalysts, and use of catalyst testing units to investigate the effects of operating parameters (the second area) with both supported and unsupported catalysts. Several supported catalysts were tested in a simulated first stage coal liquefaction application at 404{degrees}C during this performance period. A Ni-Mo hydrous titanate catalyst on an Amocat support prepared by Sandia National laboratories was tested. Other baseline experiments using AO-60 and Amocat, both Ni-Mo/Al{sub 2}O{sub 3} supported catalysts, were also made. These experiments were short duration (approximately 12 days) and monitored the initial activity of the catalysts. The results of these tests indicate that the Sandia catalyst performed as well as the commercially prepared catalysts. Future tests are planned with other Sandia preparations. The dispersed catalysts tested include sulfated iron oxide, Bayferrox iron oxide (iron oxide from Miles, Inc.), and Bailey iron oxide (micronized iron oxide from Bailey, Inc.). The effects of space velocity, temperature, and solvent-to-coal ratio on coal liquefaction activity with the dispersed catalysts were investigated. A comparison of the coal liquefaction activity of these catalysts relative to iron catalysts tested earlier, including FeOOH-impregnated coal, was made. These studies are discussed.

  18. Analysis of flammability limits for the liquefaction process of oxygen-bearing coal-bed methane

    International Nuclear Information System (INIS)

    Li, Q.Y.; Wang, L.; Ju, Y.L.

    2011-01-01

    Highlights: → A novel liquefaction and distillation process is designed for oxygen bearing coal-bed methane. → Oxygen contained in coal-bed methane is removed in distillation process. → Flammability limits are analyzed for the whole operation process. → We find explosion hazard may exist in distillation tower. → Effective measures are proposed to ensure the operation safety in distillation tower. - Abstract: A novel liquefaction and distillation process has been proposed and designed for the typical oxygen-bearing coal-bed methane (CBM), in which the impurities of the oxygen and nitrogen components are removed in the distillation column. The flammability limit theory combining with HYSYS simulation results are employed to analyze and calculate the flammability limits and the results indicate that no flammability hazard exists in the stages of compression, liquefaction and throttling. However, flammability hazard exists at the top the distillation column because the methane mole fraction decreases to the value below the upper flammability limit (UFL). The safety measures of initially removing oxygen content from the feed gas combining with the control of the bottom flowrate (flowrate of the liquid product at column bottom) are proposed to ensure the operation safety of the liquefaction process. The results reveal that the operation safety of the whole process can be guaranteed, together with high methane recovery rate and high purity of the liquid product. The applicability of the liquefaction process has also been analyzed in this paper. The simulation results can offer references for the separation of oxygen from CBM, the analysis of flammability limits and the safety measures for the whole process.

  19. Case studies on direct liquefaction of low rank Wyoming coal

    Energy Technology Data Exchange (ETDEWEB)

    Adler, P.; Kramer, S.J.; Poddar, S.K. [Bechtel Corp., San Francisco, CA (United States)

    1995-12-31

    Previous Studies have developed process designs, costs, and economics for the direct liquefaction of Illinois No. 6 and Wyoming Black Thunder coals at mine-mouth plants. This investigation concerns two case studies related to the liquefaction of Wyoming Black Thunder coal. The first study showed that reducing the coal liquefaction reactor design pressure from 3300 to 1000 psig could reduce the crude oil equivalent price by 2.1 $/bbl provided equivalent performing catalysts can be developed. The second one showed that incentives may exist for locating a facility that liquifies Wyoming coal on the Gulf Coast because of lower construction costs and higher labor productivity. These incentives are dependent upon the relative values of the cost of shipping the coal to the Gulf Coast and the increased product revenues that may be obtained by distributing the liquid products among several nearby refineries.

  20. Evaluating liquefaction potential. A case history

    International Nuclear Information System (INIS)

    Blystra, A.R.

    1991-01-01

    Several earthen hydropower embankment dams in the midwestern United States were constructed using hydraulic fill methods and are liable to liquefaction during an earthquake due to the use of very loose, saturated sand in the embankment or foundations. A case history is presented describing the methodology used in evaluating the liquefaction potential of the largest earthfill dam in Michigan. The methodology includes the use of standard penetration and cone penetration test data in the formulation of a simplified procedure. Field investigations, laboratory testing, and analyses used are described. In addition to the drilling program, field work included an extensive ground penetrating radar survey, acoustic emission testing, and an electrical resistivity survey. It was found that the lowest calculated factor of safety against liquefaction is 0.63 for a loose zone ca 140 feet below the top of the embankment, and the factor of safety against slope failure, should the zone liquefy, is 1.49. It was concluded that while liquefaction is possible, post earthquake stability is adequate. 6 refs., 3 figs., 1 tab

  1. Dispersed-phase catalysis in coal liquefaction

    International Nuclear Information System (INIS)

    Utz, B.R.; Cugini, A.V.; Frommell, E.A.

    1990-01-01

    This paper reports that the specific reaction (activation) conditions for the conversion of catalyst precursors to unsupported catalyst have a direct effect on the catalytic activity and dispersion. The importance of reaction intermediates in decomposition of ammonium heptamolybdate and ammonium tetrathiomolybdate, and the sensitivity of these intermediates to reaction conditions, were studied in coal liquefaction systems. Recent results indicate that optimization of activation conditions facilitates the formation of a highly dispersed and active form of molybdenum disulfide for coal liquefaction. The use of the catalyst precursors ammonium heptamolybdate, ammonium tetrathiomolybdate, and molybdenum trisulfide for the conversion of coal to soluble products will be discussed. The use of an unsupported dispersed-phase catalyst for direct coal liquefaction is not a novel concept and has been employed in may studies with varying success. Dispersed-phase catalysts soluble and oil-soluble salts, and as finely divided powders. While some methods of catalyst introduction give higher dispersion of the catalyst and greater activity for the liquefaction of coal, all of the techniques allow the formation of a finely dispersed inorganic phase

  2. Liquefaction Potential for Soil Deposits in Muscat, Oman

    Science.gov (United States)

    El Hussain, I. W.; Deif, A.; Girgis, M.; Al-Rawas, G.; Mohamed, A.; Al-Jabri, K.; Al-Habsi, Z.

    2015-12-01

    Muscat is located in the northeastern part of Oman on a narrow strip between Oman coast and Oman Mountains, which is the place for at least four earthquakes of order of 5.2 magnitude in the last 1300 years. The near surface geology of Muscat varies from hard rocks in the eastern, southern and western parts to dense and lose sediments in the middle and northern parts. Liquefaction occurs in saturated cohesionless soils when its shear strength decreased to zero due to the increase of pore pressure. More than 500 boreholes in Muscat area were examined for their liquefaction susceptibility based on the soil characteristics data. Only soils susceptible to liquefaction are further considered for liquefaction hazard assessment. Liquefaction occurs if the cyclic stress ratio (CSR) caused by the earthquake is higher than the cyclic resistance ratio (CRR) of the soil. CSR values were evaluated using PGA values at the surface obtained from previously conducted seismic hazard and microzonation studies. CRR for Muscat region is conducted using N values of SPT tests from numerous borehole data and the shear wave velocity results from 99 MASW surveys over the entire region. All the required corrections are conducted to get standardized (N1) 60 values, to correct shear-wave velocity, and scale the results for Mw 6.0 instead of the proposed 7.5 (magnitude scaling factor). Liquefaction hazard maps are generated using the minimum factor of safety (FS) at each site as a representative of the FS against liquefaction at that location. Results indicate that under the current level of seismic hazard, liquefaction potential is possible at few sites along the northern coast where alluvial soils and shallow ground water table are present. The expected soft soil settlement is also evaluated at each liquefiable site.

  3. Palm oil mill effluent treatment using a two-stage microbial fuel cells system integrated with immobilized biological aerated filters.

    Science.gov (United States)

    Cheng, Jia; Zhu, Xiuping; Ni, Jinren; Borthwick, Alistair

    2010-04-01

    An integrated system of two-stage microbial fuel cells (MFCs) and immobilized biological aerated filters (I-BAFs) was used to treat palm oil mill effluent (POME) at laboratory scale. By replacing the conventional two-stage up-flow anaerobic sludge blanket (UASB) with a newly proposed upflow membrane-less microbial fuel cell (UML-MFC) in the integrated system, significant improvements on NH(3)-N removal were observed and direct electricity generation implemented in both MFC1 and MFC2. Moreover, the coupled iron-carbon micro-electrolysis in the cathode of MFC2 further enhanced treatment efficiency of organic compounds. The I-BAFs played a major role in further removal of NH(3)-N and COD. For influent COD and NH(3)-N of 10,000 and 125 mg/L, respectively, the final effluents COD and NH(3)-N were below 350 and 8 mg/L, with removal rates higher than 96.5% and 93.6%. The GC-MS analysis indicated that most of the contaminants were satisfactorily biodegraded by the integrated system. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. Mongolian coal liquefaction test; Mongorutan no ekika tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, H.; Kubo, H. [Mitsui SRC Development Co. Ltd., Tokyo (Japan); Tsedevsuren, T. [National Research Center of Chemistry and Technology of Coal in Mongoria (Mongolia)

    1996-10-28

    This paper describes the results of liquefaction tests of Mongolian coals using an autoclave and a flow micro reactor. Uvdughudag coal, Hootiinhonhor coal, and Shivee-Ovoo coal were used for liquefaction tests with an autoclave. Oil yields of Uvdughudag and Hootiinhonhor coals were 55.56 wt% and 55.29 wt%, respectively, which were similar to that of Wyoming coal. Similar results were obtained, as to produced gas and water yields. These coals were found to be suitable for coal liquefaction. Lower oil yield, 42.55 wt% was obtained for Shivee-Ovoo coal, which was not suitable for liquefaction. Liquefaction tests were conducted for Uvdughudag coal with a flow micro reactor. The oil yield was 55.7 wt%, which was also similar to that of Wyoming coal, 56.1 wt%. Hydrogen consumption of Uvdughudag coal was also similar to that of Wyoming coal. From these, Uvdughudag coal can be a prospective coal for liquefaction. From the distillation distribution of oil, distillate fraction yield below 350{degree}C of Uvdughudag coal was 50.7 wt%, which was much higher than that of Wyoming coal, 35.6 wt%. Uvdughudag coal is a coal with high light oil fraction yield. 2 figs., 5 tabs.

  5. Effect of pre-swelling of coal on its liquefaction properties

    Energy Technology Data Exchange (ETDEWEB)

    Hengfu Shui; Zhicai Wang; Meixia Cao [Anhui University of Technology, Ma' anshan (China). School of Chemistry & Chemical Engineering

    2007-07-01

    The effects of pre-swelling of Shenhua coal on its liquefaction property were studied in this paper. It was found that pre-swelling treatments of Shenhua coal in three solvents, i.e toluene (TOL), N-methyl-2-pyrrolidinone (NMP) and tetralin (THN) increased its liquefaction conversion, and the liquefied product distributions were also quite different. Removal of the pre-swelling solvent from the swollen coals further increased the liquefaction conversion compared to that of the swollen coals with the swelling solvent existed in them. It was found that oil and gas yields for the liquefaction of swollen coals in NMP and TOL with swelling solvent existed dramatically decreased. Pre-swelling in THN at 120{sup o}C gave the highest liquefaction conversion, however the liquefaction conversion decreased with the increase of pre-swelling temperature in the case of NMP. TG and FTIR analyses of raw coal, the swollen coals and liquefied products were carried out and the mechanism of the effects of pre-swelling of coal on its extraction and liquefaction behaviors were probed in the paper. 12 refs., 6 figs., 3 tabs.

  6. Advanced direct liquefaction concepts for PETC generic units

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-01

    In the Advance Coal Liquefaction Concept Proposal (ACLCP) carbon monoxide (CO) and water have been proposed as the primary reagents in the pretreatment process. The main objective of this project is to develop a methodology for pretreating coal under mild conditions based on a combination of existing processes which have shown great promise in liquefaction, extraction and pyrolysis studies. The aim of this pretreatment process is to partially depolymerise the coal, eliminate oxygen and diminish the propensity for retograde reactions during subsequent liquefaction. The desirable outcome of the CO pretreatment step should be: (1) enhanced liquefaction activity and/or selectivity toward products of higher quality due to chemical modification of the coal structure; (2) cleaner downstream products; (3) overall improvement in operability and process economics.

  7. Direct liquefaction of wood through solvolysis and catalytic hydrodeoxygenation: an engineering assessment

    Energy Technology Data Exchange (ETDEWEB)

    Moffat, J.M.; Overend, J.P.

    1985-01-01

    Liquefaction of wood to produce fuel and chemical intermediates has been intensively studied over the last decade. The results of Canadian research into process feasibility are presented on the basis of two studies, the first in 1980 utilizing data of the mid-70s and the other on the basis of research conducted up to 1982. The earlier study was for a single reactor concept in which catalyst, wood and hydrogen were reacted to produce a proto-oil, while the later study embodies a two-stage concept involving dissolution of the polymer matrix followed by fractionation and catalytic upgrading using hydrodeoxygenation. Increased knowledge of the characteristics of the first stage products show that there are many component mixtures containing between 10 and 20% oxygen. Most of the oxygen is in aromatic phenol-type structures with some ether linkages, and low severity processes to deoxygenate the product while increasing the hydrogen to carbon ratio are called for. The economic prospects for a two-stage process are described on the basis of a hydrocarbon process proposed by HRI International for Kraft process lignin. These show that a mix of BTX products and fuel oil could generate a profitable rate of return. 62 references.

  8. Solvent recyclability in a multistep direct liquefaction process

    Energy Technology Data Exchange (ETDEWEB)

    Hetland, M.D.; Rindt, J.R. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-31

    Direct liquefaction research at the Energy & Environmental Research Center (EERC) has, for a number of years, concentrated on developing a direct liquefaction process specifically for low-rank coals (LRCs) through the use of hydrogen-donating solvents and solvents similar to coal-derived liquids, the water/gas shift reaction, and lower-severity reaction conditions. The underlying assumption of all of the research was that advantage could be taken of the reactivity and specific qualities of LRCs to produce a tetrahydrofuran (THF)-soluble material that might be easier to upgrade than the soluble residuum produced during direct liquefaction of high-rank coals. A multistep approach was taken to produce the THF-soluble material, consisting of (1) preconversion treatment to prepare the coal for solubilization, (2) solubilization of the coal in the solvent, and (3) polishing to complete solubilization of the remaining material. The product of these three steps can then be upgraded during a traditional hydrotreatment step. The results of the EERC`s research indicated that additional studies to develop this process more fully were justified. Two areas were targeted for further research: (1) determination of the recyclability of the solvent used during solubilization and (2) determination of the minimum severity required for hydrotreatment of the liquid product. The current project was funded to investigate these two areas.

  9. Liquefaction Microzonation of Babol City Using Artificial Neural Network

    DEFF Research Database (Denmark)

    Farrokhzad, F.; Choobbasti, A.J.; Barari, Amin

    2012-01-01

    that will be less susceptible to damage during earthquakes. The scope of present study is to prepare the liquefaction microzonation map for the Babol city based on Seed and Idriss (1983) method using artificial neural network. Artificial neural network (ANN) is one of the artificial intelligence (AI) approaches...... microzonation map is produced for research area. Based on the obtained results, it can be stated that the trained neural network is capable in prediction of liquefaction potential with an acceptable level of confidence. At the end, zoning of the city is carried out based on the prediction of liquefaction...... that can be classified as machine learning. Simplified methods have been practiced by researchers to assess nonlinear liquefaction potential of soil. In order to address the collective knowledge built-up in conventional liquefaction engineering, an alternative general regression neural network model...

  10. Semi-automated landform classification for hazard mapping of soil liquefaction by earthquake

    Science.gov (United States)

    Nakano, Takayuki

    2018-05-01

    Soil liquefaction damages were caused by huge earthquake in Japan, and the similar damages are concerned in near future huge earthquake. On the other hand, a preparation of soil liquefaction risk map (soil liquefaction hazard map) is impeded by the difficulty of evaluation of soil liquefaction risk. Generally, relative soil liquefaction risk should be able to be evaluated from landform classification data by using experimental rule based on the relationship between extent of soil liquefaction damage and landform classification items associated with past earthquake. Therefore, I rearranged the relationship between landform classification items and soil liquefaction risk intelligibly in order to enable the evaluation of soil liquefaction risk based on landform classification data appropriately and efficiently. And I developed a new method of generating landform classification data of 50-m grid size from existing landform classification data of 250-m grid size by using digital elevation model (DEM) data and multi-band satellite image data in order to evaluate soil liquefaction risk in detail spatially. It is expected that the products of this study contribute to efficient producing of soil liquefaction hazard map by local government.

  11. Wave liquefaction in soils with clay content

    DEFF Research Database (Denmark)

    Kirca, Özgür; Sumer, B. Mutlu; Fredsøe, Jørgen

    2012-01-01

    The paper presents the results of an experimental study of the influence of clay content (in silt-clay and sand-clay mixtures) on liquefaction beneath progressive waves. The experiments showed that the influence of clay content is very significant. Susceptibility of silt to liquefaction is increa...

  12. Energy consumption, destruction of exergy and boil off during the process of liquefaction, transport and regasification of liquefied natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Stradioto, Diogo Angelo; Schneider, Paulo Smith [Dept. of Mechanical Engineering. Universidade Federal do Rio Grande do Sul, Porto Alegre (Brazil)], e-mail: pss@mecanica.ufrgs.br

    2010-07-01

    A supply chain of Liquefied Natural Gas (LNG) is composed by several processes like extraction, purification, liquefaction, storage, transport, regasification and distribution. In all these stages, processes need of energy. The main objective of this work is to quantify the energy consumption, mass loss and exergy destruction occurred throughout the chain. Results show that the process of liquefaction is the largest consumer of energy. Storage and transport by ship are responsible for the bigger mass losses and regasification is the process of larger destruction of exergy. A case study is performed considering a stream of pure methane at the input of a liquefaction plant, and evaluates energy along the chain, ending up at the distribution of NG after its regasification. (author)

  13. Coal liquefaction and gas conversion contractors review conference: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    This volume contains 55 papers presented at the conference. They are divided into the following topical sections: Direct liquefaction; Indirect liquefaction; Gas conversion (methane conversion); and Advanced research liquefaction. Papers in this last section deal mostly with coprocessing of coal with petroleum, plastics, and waste tires, and catalyst studies. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  14. BP and NCB to collaborate in coal liquefaction study. [Supercritical gas extraction; dissolution in anthracene oil

    Energy Technology Data Exchange (ETDEWEB)

    1978-02-17

    British Petroleum and NCB are collaborating in a two year study of coal liquefaction which could result in a demonstration plant being built. The two liquefaction techniques which the NCB is developing at present are supercritical extraction, and dissolution in anthracene oil. A disadvantage of the latter process is that high grade coking coals must be used.

  15. Coal liquefaction and gas conversion: Proceedings. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    Volume I contains papers presented at the following sessions: AR-Coal Liquefaction; Gas to Liquids; and Direct Liquefaction. Selected papers have been processed separately for inclusion in the Energy Science and Technology Database.

  16. Two-stage implant systems.

    Science.gov (United States)

    Fritz, M E

    1999-06-01

    Since the advent of osseointegration approximately 20 years ago, there has been a great deal of scientific data developed on two-stage integrated implant systems. Although these implants were originally designed primarily for fixed prostheses in the mandibular arch, they have been used in partially dentate patients, in patients needing overdentures, and in single-tooth restorations. In addition, this implant system has been placed in extraction sites, in bone-grafted areas, and in maxillary sinus elevations. Often, the documentation of these procedures has lagged. In addition, most of the reports use survival criteria to describe results, often providing overly optimistic data. It can be said that the literature describes a true adhesion of the epithelium to the implant similar to adhesion to teeth, that two-stage implants appear to have direct contact somewhere between 50% and 70% of the implant surface, that the microbial flora of the two-stage implant system closely resembles that of the natural tooth, and that the microbiology of periodontitis appears to be closely related to peri-implantitis. In evaluations of the data from implant placement in all of the above-noted situations by means of meta-analysis, it appears that there is a strong case that two-stage dental implants are successful, usually showing a confidence interval of over 90%. It also appears that the mandibular implants are more successful than maxillary implants. Studies also show that overdenture therapy is valid, and that single-tooth implants and implants placed in partially dentate mouths have a success rate that is quite good, although not quite as high as in the fully edentulous dentition. It would also appear that the potential causes of failure in the two-stage dental implant systems are peri-implantitis, placement of implants in poor-quality bone, and improper loading of implants. There are now data addressing modifications of the implant surface to alter the percentage of

  17. Hydrothermal Liquefaction Treatment Preliminary Hazard Analysis Report

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Peter P.; Wagner, Katie A.

    2015-08-31

    A preliminary hazard assessment was completed during February 2015 to evaluate the conceptual design of the modular hydrothermal liquefaction treatment system. The hazard assessment was performed in 2 stages. An initial assessment utilizing Hazard Identification and Preliminary Hazards Analysis (PHA) techniques identified areas with significant or unique hazards (process safety-related hazards) that fall outside of the normal operating envelope of PNNL and warranted additional analysis. The subsequent assessment was based on a qualitative What-If analysis. This analysis was augmented, as necessary, by additional quantitative analysis for scenarios involving a release of hazardous material or energy with the potential for affecting the public.

  18. Summary of FY 1980 results of Sunshine Project. Development of coal liquefaction techniques; 1980 nendo sekitan ekika gijutsu no kaihatsu seika hokokusho. Sunshine keikaku itaku kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    This report summarizes the results of the 3 R and D themes for coal liquefaction techniques, pursued by the Sunshine Project; (1) development of solvent extraction type liquefaction plant, and brown coal liquefaction technique R and D demonstration surveys, (2) development of solvolysis type liquefaction plant, and (3) development of direct hydrogenation type liquefaction plant. For the theme (1), the 1 T/D test plant, solid/liquid separator and small-size continuous settlement separator are constructed, and partly completed. The elementary studies include solvent extraction type liquefaction process, materials for coal liquefaction plant and solid/liquid separation. Australia's Victoria brown coal and Chinese coal are studied to clarify the possible problems involved in liquefaction of these coal species for commercialization of the liquefaction techniques in the early stage. The elementary techniques studied include dehydration of brown coal, milling at high temperature in oil, de-ashing, and secondary and primary hydrogenation. For the theme (2), the 1 T/D plant is inspected and maintained to clarify the problems involved in the continuous operation, revamped and repaired as necessary, given preventive maintenance, and tested for operability confirmation. The elementary studies include solvolysis type liquefaction process, scale-up, hydrogenation plant for solvolysis pitch. For the item (3), the 2.4 T/D test plant is constructed, and the elementary studies are conducted, for, e.g., liquefaction reactions in the presence of an iron-based catalyst. (NEDO)

  19. Summary of FY 1980 results of Sunshine Project. Development of coal liquefaction techniques; 1980 nendo sekitan ekika gijutsu no kaihatsu seika hokokusho. Sunshine keikaku itaku kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    This report summarizes the results of the 3 R and D themes for coal liquefaction techniques, pursued by the Sunshine Project; (1) development of solvent extraction type liquefaction plant, and brown coal liquefaction technique R and D demonstration surveys, (2) development of solvolysis type liquefaction plant, and (3) development of direct hydrogenation type liquefaction plant. For the theme (1), the 1 T/D test plant, solid/liquid separator and small-size continuous settlement separator are constructed, and partly completed. The elementary studies include solvent extraction type liquefaction process, materials for coal liquefaction plant and solid/liquid separation. Australia's Victoria brown coal and Chinese coal are studied to clarify the possible problems involved in liquefaction of these coal species for commercialization of the liquefaction techniques in the early stage. The elementary techniques studied include dehydration of brown coal, milling at high temperature in oil, de-ashing, and secondary and primary hydrogenation. For the theme (2), the 1 T/D plant is inspected and maintained to clarify the problems involved in the continuous operation, revamped and repaired as necessary, given preventive maintenance, and tested for operability confirmation. The elementary studies include solvolysis type liquefaction process, scale-up, hydrogenation plant for solvolysis pitch. For the item (3), the 2.4 T/D test plant is constructed, and the elementary studies are conducted, for, e.g., liquefaction reactions in the presence of an iron-based catalyst. (NEDO)

  20. Effect of multi-stream heat exchanger on performance of natural gas liquefaction with mixed refrigerant

    Science.gov (United States)

    Chang, Ho-Myung; Lim, Hye Su; Choe, Kun Hyung

    2012-12-01

    A thermodynamic study is carried out to investigate the effect of multi-stream heat exchanger on the performance of natural gas (NG) liquefaction with mixed refrigerant (MR). A cold stream (low-pressure MR) is in thermal contact with opposite flow of two hot streams (high-pressure MR and NG feed) at the same time. In typical process simulation with commercial software (such as Aspen HYSYS®), the liquefaction performance is estimated with a method of minimum temperature approach, simply assuming that two hot streams have the same temperature. In this study, local energy balance equations are rigorously solved with temperature-dependent properties of MR and NG feed, and are linked to the thermodynamic cycle analysis. The figure of merit (FOM) is quantitatively examined in terms of UA (the product of overall heat transfer coefficient and heat exchange area) between respective streams. In a single-stage MR process, it is concluded that the temperature profile from HYSYS is difficult to realize in practice, and the FOM value from HYSYS is an over-estimate, but can be closely achieved with a proper heat-exchanger design. It is also demonstrated that there exists a unique optimal ratio in three UA's, and no direct heat exchanger between hot streams is recommended.

  1. Biomass Direct Liquefaction Options. TechnoEconomic and Life Cycle Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Tews, Iva J.; Zhu, Yunhua; Drennan, Corinne; Elliott, Douglas C.; Snowden-Swan, Lesley J.; Onarheim, Kristin; Solantausta, Yrjo; Beckman, David

    2014-07-31

    The purpose of this work was to assess the competitiveness of two biomass to transportation fuel processing routes, which were under development in Finland, the U.S. and elsewhere. Concepts included fast pyrolysis (FP), and hydrothermal liquefaction (HTL), both followed by hydrodeoxygenation, and final product refining. This work was carried out as a collaboration between VTT (Finland), and PNNL (USA). The public funding agents for the work were Tekes in Finland and the Bioenergy Technologies Office of the U.S. Department of Energy. The effort was proposed as an update of the earlier comparative technoeconomic assessment performed by the IEA Bioenergy Direct Biomass Liquefaction Task in the 1980s. New developments in HTL and the upgrading of the HTL biocrude product triggered the interest in reinvestigating this comparison of these biomass liquefaction processes. In addition, developments in FP bio-oil upgrading had provided additional definition of this process option, which could provide an interesting comparison.

  2. Histotripsy Liquefaction of Large Hematomas.

    Science.gov (United States)

    Khokhlova, Tatiana D; Monsky, Wayne L; Haider, Yasser A; Maxwell, Adam D; Wang, Yak-Nam; Matula, Thomas J

    2016-07-01

    Intra- and extra-muscular hematomas result from repetitive injury as well as sharp and blunt limb trauma. The clinical consequences can be serious, including debilitating pain and functional deficit. There are currently no short-term treatment options for large hematomas, only lengthy conservative treatment. The goal of this work was to evaluate the feasibility of a high intensity focused ultrasound (HIFU)-based technique, termed histotripsy, for rapid (within a clinically relevant timeframe of 15-20 min) liquefaction of large volume (up to 20 mL) extra-vascular hematomas for subsequent fine-needle aspiration. Experiments were performed using in vitro extravascular hematoma phantoms-fresh bovine blood poured into 50 mL molds and allowed to clot. The resulting phantoms were treated by boiling histotripsy (BH), cavitation histotripsy (CH) or a combination in a degassed water tank under ultrasound guidance. Two different transducers operating at 1 MHz and 1.5 MHz with f-number = 1 were used. The liquefied lysate was aspirated and analyzed by histology and sized in a Coulter Counter. The peak instantaneous power to achieve BH was lower than (at 1.5 MHz) or equal to (at 1 MHz) that which was required to initiate CH. Under the same exposure duration, BH-induced cavities were one and a half to two times larger than the CH-induced cavities, but the CH-induced cavities were more regularly shaped, facilitating easier aspiration. The lysates contained a small amount of debris larger than 70 μm, and 99% of particulates were smaller than 10 μm. A combination treatment of BH (for initial debulking) and CH (for liquefaction of small residual fragments) yielded 20 mL of lysate within 17.5 minutes of treatment and was found to be most optimal for liquefaction of large extravascular hematomas. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  3. Coal liquefaction technologies for producing ultra clean fuel

    International Nuclear Information System (INIS)

    Tahir, M.S.; Haq, N.U.; Nasir, H.; Islam, N.

    2011-01-01

    The expanding demand for petroleum, accompanied by the diminishing petroleum reserves and the energy security, has intensified the significance in coal liquefaction technologies (CTL) globally and specially in Pakistan. Pakistan is rich in coal resources, but short of petroleum. The Geological Survey of Pakistan based on wide spread drilling over an area of 9000 sq. km, a total of 175 billion tons of coal resource potential has been assessed. This paper overviews a general introduction on the mechanisms and processes of CLT such as direct coal liquefaction (DCL) and indirect coal liquefaction (ICL) technologies. (author)

  4. FY 1994 report on the Coal Liquefaction Committee; 1994 nendo sekitan ekika iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The paper reported the FY 1994 activities of the Coal Liquefaction Committee. The Coal Liquefaction Committee in this fiscal year was held on November 29, 1994 (1st) and March 22, 1995 (2nd), and report was made on the bituminous coal liquefaction study and state of the R and D of liquefaction base technology. Report was also made on the state of construction of bituminous coal liquefaction PP, outline of the results of the PSU operation, outline of the 11th Japan-U.S. JTM, etc. In the liquefaction base study, report/discussion were made about the improvement/rationalization of liquefaction process, study of innovative technology of coal liquefaction, study of coal liquefaction conditions, study for higher liquefaction element technology, project on the internationalization of coal liquefaction technology, etc. As to the relation of the entrained bed coal gasification power plant, report/discussion were made about survey/study on the processing of coal for coal gasification use (survey of coal kind selection, development of information processing system for coal conversion technology). Besides, as a topic, report was made on the economical evaluation/calculation of a commercial plant for brown coal liquefaction. (NEDO)

  5. Japan's New Sunshine Project. 1994 annual summary of coal liquefaction and gasification

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This paper summarizes the report for fiscal 1994 on research and development related to coal liquefaction and gasification. In the research and development of coal liquefaction technologies, reports were given on research of liquefaction characteristics of different coals and liquefaction process thereof, and on research of catalysts for the coal liquefaction. In the research and development of coal gasification technologies, reports were given on fundamental studies on gasification characteristics of different coals. In the research and development of liquefaction technologies for bituminous coal, reports were given on design, construction and operation of a bituminous coal liquefaction pilot plant with a capacity of 150 t/d, and the operation supporting studies on the pilot plant. In the fundamental research on the coal liquefaction process, reports were given on refining technologies and utilization of the refined materials, and studies on environment preservation in applying the coal liquefaction technologies. In the research on hydrogen manufacturing technologies by using the fundamental coal technology, reports were given on design, construction and operational studies of a pilot plant. In the research and development of the coal gasification technologies, reports were given on development of a jet-flow gasified coal electric power plant, selection of coals, and development of a data processing system. (NEDO)

  6. Achievement report for fiscal 1982 on Sunshine Program. Research and development of coal liquefaction technology (Conceptual designs for coal liquefaction pilot plants - Solvent extraction liquefaction process); 1982 nendo sekitan ekika gijutsu no kenkyu kaihatsu seika hokokusho. Sekitan ekika pilot plant no gainen sekkei (yozai chushutsu ekikaho)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-03-01

    This research aims to prepare conceptual designs for a 250t/d-class and 500t/d-class coal liquefaction pilot plants based on the achievement of research on solvent extraction liquefaction of coal. It also aims to define the solvent extraction process and provide decision-making material relative to the development and promotion of coal liquefaction technologies in the future. Development started in 1978 of the technology of solvent extraction liquefaction of coal, and a 1t/d PDU (process development unit) was completed in 1981. Studies through its operation have continued for more than 3000 hours already, and technical data are being accumulated steadily. Techniques acquired through operating the 1t/d PDU have been put together, and rough process conditions are established. A rough process result is achieved of the same conditions. In these two respects, the newly developed process is equal to other processes. The phenomena in this process are roughly grasped. It is deemed that, with the existing technique combined with the technique acquired here, a technological level has been reached where conceptual designs of large pilot plants may be worked out for solvent extraction liquefaction of coal. Under the circumstances, with a view to developing a commercial plant whose main products will be fuel oils, conceptual designs are prepared for large pilot plants, and are compiled into this report. (NEDO)

  7. Seismic behavior of breakwaters on complex ground by numerical tests: Liquefaction and post liquefaction ground settlements

    Science.gov (United States)

    Gu, Linlin; Zhang, Feng; Bao, Xiaohua; Shi, Zhenming; Ye, Guanlin; Ling, Xianzhang

    2018-04-01

    A large number of breakwaters have been constructed along coasts to protect humans and infrastructures from tsunamis. There is a risk that foundation soils of these structures may liquefy, or partially liquefy during the earthquake preceding a tsunami, which would greatly reduce the structures' capacity to resist the tsunami. It is necessary to consider not only the soil's liquefaction behavior due to earthquake motions but also its post-liquefaction behavior because this behavior will affect the breakwater's capacity to resist an incoming tsunami. In this study, numerical tests based on a sophisticated constitutive model and a soil-water coupled finite element method are used to predict the mechanical behavior of breakwaters and the surrounding soils. Two real breakwaters subjected to two different seismic excitations are examined through numerical simulation. The simulation results show that, earthquakes affect not only the immediate behavior of breakwaters and the surrounding soils but also their long-term settlements due to post-earthquake consolidation. A soil profile with thick clayey layers beneath liquefied soil is more vulnerable to tsunami than a soil profile with only sandy layers. Therefore, quantitatively evaluating the seismic behavior of breakwaters and surrounding soils is important for the design of breakwater structures to resist tsunamis.

  8. Coal liquefaction policy in China: Explaining the policy reversal since 2006

    International Nuclear Information System (INIS)

    Rong Fang; Victor, David G.

    2011-01-01

    China has emerged as a leader in coal liquefaction. While the country's abundant coal resources and acute concerns about oil security help explain China's interest in liquefaction, the driving forces for this industry are complicated and policy has been inconsistent. Since 2006 Beijing has tried to slow down the development of liquefaction; even as China has become more dependent on imported oil, the central government has been wary about the large impact of liquefaction technologies on scarce resources such as water. However, local government officials in coal rich areas have strong incentives to pour investment into the technology, which helps explain the uneven development and policy. The future of coal liquefaction will depend on how these forces unfold along with major Beijing-led reforms in the Chinese coal industry, which is closing smaller mines and favoring the emergence of larger coal producing firms. Those reforms will have mixed effects on liquefaction. They temporarily contribute to higher prices for coal while over the longer term creating coal companies that have much greater financial and technical skills needed to deploy technologies such as coal liquefaction at a scale needed if this energy pathway is to be competitive with conventional sources of liquid fuel. - Highlights: ► We explain swings in Chinese policy on coal liquefaction, a possible substitute for imported oil. ► Since 2006 Beijing's support has waned due to fears about environmental impacts and cost of liquefaction. ► Local governments in some coal rich regions remain strongly supportive. ► Volatile oil prices and rising coal prices make this industry more risky than previously thought. ► Consolidation of the coal industry will have mixed effects on viability of liquefaction projects.

  9. Influence of clay content on wave-induced liquefaction

    DEFF Research Database (Denmark)

    Kirca, V.S. Ozgur; Sumer, B. Mutlu; Fredsøe, Jørgen

    2014-01-01

    of measurements were carried out: (1) pore-water pressure measurements across the soil depth and (2) water-surface elevation measurements. These measurements were synchronized with video recordings of the liquefaction process from the side. The ranges of the various quantities in the experiments were wave height...... of silt and clay was not liquefied. Sand may become prone to liquefaction with the introduction of clay, contrary to the general perception that this type of sediment is normally liquefaction-resistant under waves. For instance, sand with d50 50:4 mmwas liquefied with CC510:8%, whereas sand with d50 50...

  10. Coal liquefaction committee report for fiscal 1981; 1981 nendo sekitan ekika iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-03-01

    For the assurance of smooth progress of coal technology development endeavors, the New Energy and Industrial Technology Development Organization (NEDO) has installed coal technology development committees (general committee on coal technologies, coal liquefaction committee, plant materials committee, coal type survey committee, total system committee, and coal gasification committee). The coal liquefaction committee deliberates and evaluates liquefaction technology and propels forward smoothly the efforts to develop the technology. Under the coal liquefaction committee, there are four subcommittees, which are the 1st subcommittee (primary liquefaction subcommittee), 2nd subcommittee (solid/liquid separation subcommittee), 3rd subcommittee (secondary hydrogenation subcommittee), and the 4th subcommittee (brown coal liquefaction subcommittee). The 2nd and 3rd subcommittees deal with common tasks as they were studied in fiscal 1980. The 1st subcommittee incorporates into itself the old subcommittees that respectively worked on the three liquefaction processes (the direct hydrogenation process, the solvent extraction process, and the Solvolysis process), and is designed to provide a site for information exchange. A brown coal liquefaction committee is incorporated into the coal liquefaction committee as the 4th subcommittee. This report is a compilation of the agendas of the respective subcommittees of the coal liquefaction committee. (NEDO)

  11. Quantitative characterization of the aqueous fraction from hydrothermal liquefaction of algae

    Energy Technology Data Exchange (ETDEWEB)

    Maddi, Balakrishna; Panisko, Ellen; Wietsma, Thomas; Lemmon, Teresa; Swita, Marie; Albrecht, Karl; Howe, Daniel

    2016-10-01

    Aqueous streams generated from hydrothermal liquefaction contain approximately 30% of the total carbon present from the algal feed. Hence, this aqueous carbon must be utilized to produce liquid fuels and/or specialty chemicals for economic sustainability of hydrothermal liquefaction on industrial scale. In this study, aqueous fractions produced from the hydrothermal liquefaction of fresh water and saline water algal cultures were analyzed using a wide variety of analytical instruments to determine their compositional characteristics. This study will also inform researchers designing catalysts for down-stream processing such as high-pressure catalytic conversion of organics in aqueous phase, catalytic hydrothermal gasification, and biological conversions. Organic chemical compounds present in all eight aqueous fractions were identified using two-dimensional gas chromatography equipped with time-of-flight mass spectrometry. Identified compounds include organic acids, nitrogen compounds and aldehydes/ketones. Conventional gas chromatography and liquid chromatography methods were utilized to quantify the identified compounds. Inorganic species in the aqueous stream of hydrothermal liquefaction of algae were identified using ion chromatography and inductively coupled plasma optical emission spectrometer. The concentrations of organic chemical compounds and inorganic species are reported. The amount quantified carbon ranged from 45 to 72 % of total carbon in the aqueous fractions.

  12. Experimental study on the liquefaction of cellulose in supercritical ethanol

    Science.gov (United States)

    Peng, Jinxing; Liu, Xinyuan; Bao, Zhenbo

    2018-03-01

    Cellulose is the major composition of solid waste for producing biofuel; cellulose liquefaction is helpful for realizing biomass supercritical liquefaction process. This paper is taking supercritical ethanol as the medium, liquefied cellulose with the intermittence installation of high press cauldron. Experiments have studied technical condition and the technology parameter of cellulose liquefaction in supercritical ethanol, and the pyrolysis mechanism was analysed based on the pyrolysis product. Results show that cellulose can be liquefied, can get good effect through appropriate technology condition. Under not catalyst, highest liquefaction rate of cellulose can reach 73.5%. The composition of the pyrolysis product was determined by GC-MS.

  13. Labor Union Effects on Innovation and Commercialization Productivity: An Integrated Propensity Score Matching and Two-Stage Data Envelopment Analysis

    Directory of Open Access Journals (Sweden)

    Dongphil Chun

    2015-04-01

    Full Text Available Research and development (R&D is a critical factor in sustaining a firm’s competitive advantage. Accurate measurement of R&D productivity and investigation of its influencing factors are of value for R&D productivity improvements. This study is divided into two sections. The first section outlines the innovation and commercialization stages of firm-level R&D activities. This section analyzes the productivity of each stage using a propensity score matching (PSM and two-stage data envelopment analysis (DEA integrated model to solve the selection bias problem. Second, this study conducts a comparative analysis among subgroups categorized as labor unionized or non-labor unionized on productivity at each stage. We used Korea Innovation Survey (KIS data for analysis using a sample of 400 Korean manufacturers. The key findings of this study include: (1 firm innovation and commercialization productivity are balanced and show relatively low innovation productivity; and (2 labor unions have a positive effect on commercialization productivity. Moreover, labor unions are an influential factor in determining manufacturing firms’ commercialization productivity.

  14. Prediction of strain energy-based liquefaction resistance of sand-silt mixtures: An evolutionary approach

    Science.gov (United States)

    Baziar, Mohammad H.; Jafarian, Yaser; Shahnazari, Habib; Movahed, Vahid; Amin Tutunchian, Mohammad

    2011-11-01

    Liquefaction is a catastrophic type of ground failure, which usually occurs in loose saturated soil deposits under earthquake excitations. A new predictive model is presented in this study to estimate the amount of strain energy density, which is required for the liquefaction triggering of sand-silt mixtures. A wide-ranging database containing the results of cyclic tests on sand-silt mixtures was first gathered from previously published studies. Input variables of the model were chosen from the available understandings evolved from the previous studies on the strain energy-based liquefaction potential assessment. In order to avoid overtraining, two sets of validation data were employed and a particular monitoring was made on the behavior of the evolved models. Results of a comprehensive parametric study on the proposed model are in accord with the previously published experimental observations. Accordingly, the amount of strain energy required for liquefaction onset increases with increase in initial effective overburden pressure, relative density, and mean grain size. The effect of nonplastic fines on strain energy-based liquefaction resistance shows a more complicated behavior. Accordingly, liquefaction resistance increases with increase in fines up to about 10-15% and then starts to decline for a higher increase in fines content. Further verifications of the model were carried out using the valuable results of some downhole array data as well as centrifuge model tests. These verifications confirm that the proposed model, which was derived from laboratory data, can be successfully utilized under field conditions.

  15. A comprehensive review on two-stage integrative schemes for the valorization of dark fermentative effluents.

    Science.gov (United States)

    Sivagurunathan, Periyasamy; Kuppam, Chandrasekhar; Mudhoo, Ackmez; Saratale, Ganesh D; Kadier, Abudukeremu; Zhen, Guangyin; Chatellard, Lucile; Trably, Eric; Kumar, Gopalakrishnan

    2017-12-21

    This review provides the alternative routes towards the valorization of dark H 2 fermentation effluents that are mainly rich in volatile fatty acids such as acetate and butyrate. Various enhancement and alternative routes such as photo fermentation, anaerobic digestion, utilization of microbial electrochemical systems, and algal system towards the generation of bioenergy and electricity and also for efficient organic matter utilization are highlighted. What is more, various integration schemes and two-stage fermentation for the possible scale up are reviewed. Moreover, recent progress for enhanced performance towards waste stabilization and overall utilization of useful and higher COD present in the organic source into value-added products are extensively discussed.

  16. Liquefaction susceptibility of fine-grained soils: preliminary study report. Final report, September 1985-March 1986

    Energy Technology Data Exchange (ETDEWEB)

    Chang, N.Y.

    1987-09-01

    Soil liquefaction, a hazardous ground failure induced by strong motion earthquakes, can cause catastrophic damage to structures such as dams, bridges, power plants, and water-front structures and may involve great losses of life. Examples of liquefaction and resulting damage were observed during the Alaska (1964), Niigata, Japan (1964), and Tangshan, China (1976), earthquakes. Ground failure due to earthquake-induced soil liquefaction may manifest itself as excessive settlement, loss of bearing capacity, sand boiling, and flow slides. The liquefaction potential of clean sands has been studied extensively for the last two decades. However, case histories revealed that liquefied sands were seldom clean. They may contain various percentages of silt or clay or both. In fact, the Chinese observation in the Tansghan earthquake indicated that some cohesive soils may have liquefied. If this indeed had happened, then structures underlain by fine-grained soils, with a marginal safety factor based on the liquefaction criteria normally applied to sands, may actually be unsafe. Thus there is an urgent need for establishing new criteria for the liquefaction susceptibility of soils to include those identified as fine-grained. The author, Professor N.Y. Chang of the University of Colorado at Denver, visited several Chinese agencies and and universities in and near Beijing, China, in the summer of 1985 in an attempt to investigate and verify reported data on the liquefaction of cohesive soils during the Tangshan earthquake of 1976 and to negotiate cooperative research into the problem. This report presents the result of supportive literature review and the findings of the China trip.

  17. Effects of Long-Duration Ground Motions on Liquefaction Hazards

    Science.gov (United States)

    Greenfield, Michael W.

    Soil liquefaction during past earthquakes has caused extensive damage to buildings, bridges, dam, pipelines and other elements of infrastructure. Geotechnical engineers use empirical observations from earthquake case histories in conjunction with soil mechanics to predict the behavior of liquefiable soils. However, current empirical databases are insufficient to evaluate the behavior of soils subject to long-duration earthquakes, such as a possible Mw = 9.0 Cascadia Subduction Zone earthquake. The objective of this research is to develop insight into the triggering and effects of liquefaction due to long-duration ground motions and to provide recommendations for analysis and design. Recorded ground motions from 21 case histories with surficial evidence of liquefaction showed marked differences in soil behavior before and after liquefaction was triggered. In some cases, strong shaking continued for several minutes after the soil liquefied, and a variety of behaviors were observed including dilation pulses, continued softening due to soil fabric degradation, and soil stiffening due to pore pressure dissipation and drainage. Supplemental field and laboratory investigations were performed at three sites that liquefied during the 2011 Mw = 9.0 Tohoku earthquake. The recorded ground motions and field investigation data were used in conjunction with laboratory observations, analytical models, and numerical models to evaluate the behavior of liquefiable soils subjected to long-duration ground motions. Observations from the case histories inspired a framework to predict ground deformations based on the differences in soil behavior before and after liquefaction has triggered. This framework decouples the intensity of shaking necessary to trigger liquefaction from the intensity of shaking that drives deformation by identifying the time when liquefaction triggers. The timing-based framework promises to dramatically reduce the uncertainty in deformation estimates compared to

  18. Japan`s sunshine project. 17.. 1992 annual summary of coal liquefaction and gasification

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    This report describes the achievement of coal liquefaction and gasification technology development in the Sunshine Project for FY 1992. It presents the research and development of coal liquefaction which includes studies on reaction mechanism of coal liquefaction and catalysts for coal liquefaction, the research and development of coal gasification technologies which includes studies on gasification characteristics of various coals and improvement of coal gasification efficiency, the development of bituminous coal liquefaction which includes engineering, construction and operation of a bituminous coal liquefaction pilot plant and research by a process supporting unit (PSU), the development of brown coal liquefaction which includes research on brown coal liquefaction with a pilot plant and development of techniques for upgrading coal oil from brown coal, the development of common base technologies which includes development of slurry letdown valves and study on upgrading technology of coal-derived distillates, the development of coal-based hydrogen production technology with a pilot plant, the development of technology for entrained flow coal gasification, the assessment of coal hydrogasification, and the international co-operation. 4 refs., 125 figs., 39 tabs.

  19. Energy demand in Portuguese manufacturing: a two-stage model

    International Nuclear Information System (INIS)

    Borges, A.M.; Pereira, A.M.

    1992-01-01

    We use a two-stage model of factor demand to estimate the parameters determining energy demand in Portuguese manufacturing. In the first stage, a capital-labor-energy-materials framework is used to analyze the substitutability between energy as a whole and other factors of production. In the second stage, total energy demand is decomposed into oil, coal and electricity demands. The two stages are fully integrated since the energy composite used in the first stage and its price are obtained from the second stage energy sub-model. The estimates obtained indicate that energy demand in manufacturing responds significantly to price changes. In addition, estimation results suggest that there are important substitution possibilities among energy forms and between energy and other factors of production. The role of price changes in energy-demand forecasting, as well as in energy policy in general, is clearly established. (author)

  20. On the risk of liquefaction of buffer and backfill

    Energy Technology Data Exchange (ETDEWEB)

    Pusch, R. [Geodevelopment AB, Lund (Sweden)

    2000-10-01

    The necessary prerequisites for liquefaction of buffers and backfills in a KBS-3 repository exist but the stress conditions and intended densities practically eliminate the risk of liquefaction for single earthquakes with magnitudes up to M=8 and normal duration. For buffers rich in expandable minerals it would be possible to reduce the density at water saturation to 1,700 - 1,800 kg/m{sup 3} or even less without any significant risk of liquefaction, while the density at saturation of backfills with 10 - 15% expandable clay should not be reduced to less than about 1,900 kg/m{sup 3}. Since the proposed densities of both buffers and backfills will significantly exceed these minimum values it is concluded that there is no risk of liquefaction of the engineered soil barriers in a KBS-3 repository even for very significant earthquakes.

  1. On the risk of liquefaction of buffer and backfill

    International Nuclear Information System (INIS)

    Pusch, R.

    2000-10-01

    The necessary prerequisites for liquefaction of buffers and backfills in a KBS-3 repository exist but the stress conditions and intended densities practically eliminate the risk of liquefaction for single earthquakes with magnitudes up to M=8 and normal duration. For buffers rich in expandable minerals it would be possible to reduce the density at water saturation to 1,700 - 1,800 kg/m 3 or even less without any significant risk of liquefaction, while the density at saturation of backfills with 10 - 15% expandable clay should not be reduced to less than about 1,900 kg/m 3 . Since the proposed densities of both buffers and backfills will significantly exceed these minimum values it is concluded that there is no risk of liquefaction of the engineered soil barriers in a KBS-3 repository even for very significant earthquakes

  2. Assessment of Soil Liquefaction Potential Based on Numerical Method

    DEFF Research Database (Denmark)

    Choobasti, A. Janalizadeh; Vahdatirad, Mohammad Javad; Torabi, M.

    2012-01-01

    Paying special attention to geotechnical hazards such as liquefaction in huge civil projects like urban railways especially in susceptible regions to liquefaction is of great importance. A number of approaches to evaluate the potential for initiation of liquefaction, such as Seed and Idriss...... simplified method have been developed over the years. Although simplified methods are available in calculating the liquefaction potential of a soil deposit and shear stresses induced at any point in the ground due to earthquake loading, these methods cannot be applied to all earthquakes with the same...... accuracy, also they lack the potential to predict the pore pressure developed in the soil. Therefore, it is necessary to carry out a ground response analysis to obtain pore pressures and shear stresses in the soil due to earthquake loading. Using soil historical, geological and compositional criteria...

  3. Cooperative research in coal liquefaction. Final report, May 1, 1990-- April 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Huffman, G.P. [ed.

    1992-02-15

    The Consortium for Fossil Fuel Liquefaction Science (CFFLS) is currently engaged in a three year contract with the US Department of Energy investigating a range of research topics dealing with direct coal liquefaction. This report summarizes the results of this program in its second year, from May 1, 1990 to April 30, 1991. Accomplishments for this period are presented for the following tasks: Iron-based catalysts for coal liquefaction, exploratory research on coal conversion, novel coal liquefaction concepts, and novel catalysts for coal liquefaction.

  4. A novel process for small-scale pipeline natural gas liquefaction

    International Nuclear Information System (INIS)

    He, T.B.; Ju, Y.L.

    2014-01-01

    Highlights: • A novel process was proposed to liquefy natural gas by utilizing the pressure exergy. • The process is zero energy consumption. • The maximum liquefaction rate of the process is 12.61%. • The maximum exergy utilization rate is 0.1961. • The economic analysis showed that the payback period of the process is quit short. - Abstract: A novel process for small-scale pipeline natural gas liquefaction is designed and presented. The novel process can utilize the pressure exergy of the pipeline to liquefy a part of natural gas without any energy consumption. The thermodynamic analysis including mass, energy balance and exergy analysis are adopted in this paper. The liquefaction rate and exergy utilization rate are chosen as the objective functions. Several key parameters are optimized to approach the maximum liquefaction rate and exergy utilization rate. The optimization results showed that the maximum liquefaction rate is 12.61% and the maximum exergy utilization rate is 0.1961. What is more, the economic performances of the process are also discussed and compared by using the maximum liquefaction rate and exergy utilization rate as indexes. In conclusion, the novel process is suitable for pressure exergy utilization due to its simplicity, zero energy consumption and short payback period

  5. Characterisation of Liquefaction Effects for Beyond-Design Basis Safety Assessment of Nuclear Power Plants

    Science.gov (United States)

    Bán, Zoltán; Győri, Erzsébet; János Katona, Tamás; Tóth, László

    2015-04-01

    Preparedness of nuclear power plants to beyond design base external effects became high importance after 11th of March 2011 Great Tohoku Earthquakes. In case of some nuclear power plants constructed at the soft soil sites, liquefaction should be considered as a beyond design basis hazard. The consequences of liquefaction have to be analysed with the aim of definition of post-event plant condition, identification of plant vulnerabilities and planning the necessary measures for accident management. In the paper, the methodology of the analysis of liquefaction effects for nuclear power plants is outlined. The case of Nuclear Power Plant at Paks, Hungary is used as an example for demonstration of practical importance of the presented results and considerations. Contrary to the design, conservatism of the methodology for the evaluation of beyond design basis liquefaction effects for an operating plant has to be limited to a reasonable level. Consequently, applicability of all existing methods has to be considered for the best estimation. The adequacy and conclusiveness of the results is mainly limited by the epistemic uncertainty of the methods used for liquefaction hazard definition and definition of engineering parameters characterizing the consequences of liquefaction. The methods have to comply with controversial requirements. They have to be consistent and widely accepted and used in the practice. They have to be based on the comprehensive database. They have to provide basis for the evaluation of dominating engineering parameters that control the post-liquefaction response of the plant structures. Experience of Kashiwazaki-Kariwa plant hit by Niigata-ken Chuetsu-oki earthquake of 16 July 2007 and analysis of site conditions and plant layout at Paks plant have shown that the differential settlement is found to be the dominating effect in case considered. They have to be based on the probabilistic seismic hazard assessment and allow the integration into logic

  6. Report on results for fiscal 1997 on development of coal liquefaction technology . Development of liquefaction base technology (studies on development and internationalization of environmentally benign coal liquefaction technology); 1997 nendo sekitan ekika gijutsu seika hokokusho. Ekika kiban gijutsu no kaihatsu (kankyo chowagata sekitan ekika gijutsu no kaihatsu oyobi kokusaika kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The research objective is the development of environmentally benign coal liquefaction technology and the studies on internationalization of coal liquefaction technology. Implemented for the former are (1) research on improvement and rationalization of liquefaction process and (2) research on advancement of liquefaction base technology. In (1), studies were made on in-oil preprocessing technology and scale suppressing measures for the purpose of obtaining reform/high grade of coal, and on improvement of liquefied oil collecting ratio, sophistication of coal slurry and attainment of light oil/high grade from liquefied crude oil for the purpose of optimizing liquefaction reactive conditions and improving a solvent. In (2), in developing high activity/high dispersion type new catalysts, catalytic sufurization behavior and activity manifestation mechanism were explored, as were iron hydroxide based iron ore properties and liquefaction reactive characteristics. The initial reactive characteristics of liquefaction for example were investigated for the purpose of collecting basic data for expanding kinds of coal. In order to attain the latter objective of the research, a feasibility study of liquefaction location was conducted, as were the investigation including sampling of iron ore for catalytic material and the investigation of coal gasification technology. After the completion of the Australian brown coal liquefaction project, the development of the coal liquefaction technology commenced in fiscal 1994 produced a number of useful records and ended in 1997. (NEDO)

  7. Coal liquefaction process streams characterization and evaluation. Quarterly technical progress report, October 1--December 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, G.A.; Brandes, S.D.; Winschel, R.A.; Burke, F.P.

    1992-03-01

    CONSOL R&D is conducting a three-year program to characterize process and product streams from direct coal liquefaction process development projects. The program objectives are two-fold: (1) to obtain and provide appropriate samples of coal liquids for the evaluation of analytical methodology, and (2) to support ongoing DOE-sponsored coal liquefaction process development efforts. The two broad objectives have considerable overlap and together serve to provide a bridge between process development and analytical chemistry.

  8. Fiscal 1991 report. Coal liquefaction committee; 1991 nendo sekitan ekika iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-03-01

    The committee in this fiscal year had the 1st meeting in July 1991, the 2nd in August 1991, and the 3rd in March 1992, when fiscal 1990 research and development results, fiscal 1991 research and development programs, fiscal 1991 research and development results, etc., were reported and deliberated. At the 2nd meeting, the meaning of coal liquefaction technology development and how to go ahead with the task were described, which topic for discussion was entitled 'How coal liquefaction technology should be for the 21st century.' After discussion, it was agreed upon that a coal liquefaction technology package be completed in fiscal 2000 based on the absorption of each other's findings and on the utilization of basic studies common to both to be realized through the exchange of technologies between the brown coal liquefaction project and the bituminous coal liquefaction project. Under the brown coal liquefaction project, a 50 ton/day pilot plant was built and operated in Victoria, Australia, and the operation was completed in October 1990. The results of research and development under the coal brown liquefaction project will be compiled by fiscal 1993. (NEDO)

  9. Comparison of the sand liquefaction estimated based on codes and practical earthquake damage phenomena

    Science.gov (United States)

    Fang, Yi; Huang, Yahong

    2017-12-01

    Conducting sand liquefaction estimated based on codes is the important content of the geotechnical design. However, the result, sometimes, fails to conform to the practical earthquake damages. Based on the damage of Tangshan earthquake and engineering geological conditions, three typical sites are chosen. Moreover, the sand liquefaction probability was evaluated on the three sites by using the method in the Code for Seismic Design of Buildings and the results were compared with the sand liquefaction phenomenon in the earthquake. The result shows that the difference between sand liquefaction estimated based on codes and the practical earthquake damage is mainly attributed to the following two aspects: The primary reasons include disparity between seismic fortification intensity and practical seismic oscillation, changes of groundwater level, thickness of overlying non-liquefied soil layer, local site effect and personal error. Meanwhile, although the judgment methods in the codes exhibit certain universality, they are another reason causing the above difference due to the limitation of basic data and the qualitative anomaly of the judgment formulas.

  10. Fiscal 1994 report. Liquefaction key technology subcommittee; 1994 nendo ekika kiban gijutsu bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The subcommittee held the 1st meeting in August 1994 and the 2nd in March 1995, when preceding fiscal year's research results, fiscal 1994 research plans, fiscal 1994 research results, etc., were introduced, and deliberated. In the study of hydrorefining of naphtha, kerosene, and light oil fractions, a nitrogen concentration level of not more than 5 ppm was achieved by refining oils from Indonesian coal. Studies were also made about the two-step hydrorefining system, the relationship between the coal oil refining level and sludge formation, etc. In the research for the development of novel catalysts for upgrading coal oil, the active life of a nickel-supporting catalyst for hydrogenation at the 1st step was somewhat prolonged with an increase in the amount of nickel. In the study of coal liquefaction conditions, an AWIP method was deliberated, wherein liquefaction process waste water was utilized as one of catalytic component adjusting materials. For upgrading liquefaction key technologies, studies were made for catalyst improvement and pretreatment method development, and about the behavior of liquefaction reaction in a high boiling solvent-aided process. (NEDO)

  11. FY 1992 report on the Coal Liquefaction Committee; 1992 nendo sekitan ekika iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-03-01

    The paper reported activities of the Coal Liquefaction Committee in FY 1992. In the 1st committee meeting, report/discussion were made of the summary of the FY 1992 R and D plan on the bituminous coal liquefaction, brown coal liquefaction and the common/basic technology. Further, the following were reported as topics: results of the operation by bituminous coal liquefaction PSU and small equipment, state of arrangement of the results of the brown coal liquefaction project, making of the basic policy for development of the common/basic technology, construction of package of coal liquefaction technology. In the 2nd committee meeting, the summary of the results of the FY 1992 R and D was reported/discussed. As to the development of bituminous coal liquefaction technology, study using pilot plant and support study were reported. Concerning the development of brown coal liquefaction technology, study using a 50t/d pilot plant and complementary study of operation. Relating to the development of the common/basic technology, trial manufacture/development of plant equipment/materials, survey of selection of coal kind, etc. The paper also reported a scheme on the evaluation of efficiency of the brown coal liquefaction process. (NEDO)

  12. Energy-based numerical models for assessment of soil liquefaction

    Directory of Open Access Journals (Sweden)

    Amir Hossein Alavi

    2012-07-01

    Full Text Available This study presents promising variants of genetic programming (GP, namely linear genetic programming (LGP and multi expression programming (MEP to evaluate the liquefaction resistance of sandy soils. Generalized LGP and MEP-based relationships were developed between the strain energy density required to trigger liquefaction (capacity energy and the factors affecting the liquefaction characteristics of sands. The correlations were established based on well established and widely dispersed experimental results obtained from the literature. To verify the applicability of the derived models, they were employed to estimate the capacity energy values of parts of the test results that were not included in the analysis. The external validation of the models was verified using statistical criteria recommended by researchers. Sensitivity and parametric analyses were performed for further verification of the correlations. The results indicate that the proposed correlations are effectively capable of capturing the liquefaction resistance of a number of sandy soils. The developed correlations provide a significantly better prediction performance than the models found in the literature. Furthermore, the best LGP and MEP models perform superior than the optimal traditional GP model. The verification phases confirm the efficiency of the derived correlations for their general application to the assessment of the strain energy at the onset of liquefaction.

  13. A study on the hydrotreating of coal hydro liquefaction residue and its kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Huang, J.; Lu, X.; Zhang, D.; Gao, J. [Department of Chemical Engineering for Energy Resources, East China University of Science and Technology, Shanghai (China)

    2010-09-15

    Hydro-conversion of coal hydro liquefaction residue obtained from a 6 t/day pilot plant of Shenhua Group in Shanghai was carried out under the hydrotreating condition. The coal hydro liquefaction residue and its product were extracted in sequence with n-hexane, toluene and tetrahydrofuran in a Soxhlet apparatus. The n-hexane soluble fractions increased with the increase of reaction temperature and time. Its amount increased from 14.14% to a maximum of 40.86% under the conditions of 470 {sup o}C and 30 min, which meant that moderate extension of coal residence time in the coal hydro liquefaction reactor is beneficial to the increase of oil yield. A 4-lumped kinetic model of coal hydro liquefaction residue hydro-conversion was performed using solubility-based lumped fractions. In the model, the tetrahydrofuran insoluble fractions were classified into two parts: easily reactive part and unreactive part. The kinetic parameters were estimated by a fourth-order Runge-Kutta method and a nonlinear least squares method, and the apparent activation energies were calculated according to the Arrhenius Equation. A large quantity of total catalyst consisting of remained liquefaction catalyst, part of the mineral from raw coal and additive Fe-based catalyst could considerably reduce the apparent activation energy of hydro-conversion for the toluene insoluble/tetrahydrofuran insoluble fractions to 36.79 kJ-mol{sup -1}. The calculated values of the model coincided well with the experimental values. (authors)

  14. Numerical analysis of stone columns in mitigating liquefaction effects in embankment fills

    Energy Technology Data Exchange (ETDEWEB)

    Borghei, Z.; Soroush, A. [Amirkabir University of Technology, Tehran, (Iran, Islamic Republic of); Noorzad, A. [Power and Water University of Technology, Tehran, (Iran, Islamic Republic of)

    2010-07-01

    The traditional approach to liquefaction in embankment fills is to use in-situ densification. The use of stone columns offers the possibility of preventing liquefaction and associated settlements while reducing the cost and time required for treatment. This paper investigated the behaviour of stone columns using a numerical method. The study focused on a case study, a sand layer beneath two wall tanks, butane and propane NGL, located on Siri Island, Persian Gulf, Iran. Numerical analyses were carried out to evaluate the rate of excess pore pressure build-up in the improved ground. The numerical model results were compared to the simulation results from a centrifuge test for a uniform 19m-thick liquefiable sand layer. The numerical methodology was verified. The results showed that the stone columns can significantly increase the rate of pore pressure dissipation and reduce the settlement. It was found that the installation process densifies the surrounding soil, decreasing the liquefaction potential.

  15. Report on 1979 result of Sunshine Project (detailed design). Part 1. Forty t/day solvolysis coal liquefaction pilot plant; 1979 nendo 40T/nichi solvolysis sekitan pilot plant shosai sekkei. 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-03-01

    The subject design documents are the compilation of the result of the design operation for the 'detailed design of 40 t/day class solvolysis coal liquefaction pilot plant'. The design of this pilot plant was conducted using, as the fundamental reference, the basic data provided by Kyushu National Industrial Research Institute and Kyushu University and the results of a contract research on '1 t/day class solvolysis coal liquefaction plant'. The subject detailed design was intended for Phase 1 centering on a single stage liquefaction - coal liquefaction (transformation into pitch) by solvolysis liquefaction reaction. The areas covered consists of the pre-treatment process, material mixing process, reaction process, reaction freezing process, coke separation process, SR recovery process, pitch refining process, utility facilities, and waste water treatment facilities. Incidentally, the processes for which the design operation has been completed this year, particularly the reaction process, coke separation process, SR recovery process, etc., are in the field untrodden technologically in the world; therefore, their design method is supposed to be established from the results of the R and D on coal liquefaction, '1 t/day class solvolysis coal liquefaction plant.' (NEDO)

  16. Report on 1979 result of Sunshine Project (detailed design). Part 1. Forty t/day solvolysis coal liquefaction pilot plant; 1979 nendo 40T/nichi solvolysis sekitan pilot plant shosai sekkei. 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-03-01

    The subject design documents are the compilation of the result of the design operation for the 'detailed design of 40 t/day class solvolysis coal liquefaction pilot plant'. The design of this pilot plant was conducted using, as the fundamental reference, the basic data provided by Kyushu National Industrial Research Institute and Kyushu University and the results of a contract research on '1 t/day class solvolysis coal liquefaction plant'. The subject detailed design was intended for Phase 1 centering on a single stage liquefaction - coal liquefaction (transformation into pitch) by solvolysis liquefaction reaction. The areas covered consists of the pre-treatment process, material mixing process, reaction process, reaction freezing process, coke separation process, SR recovery process, pitch refining process, utility facilities, and waste water treatment facilities. Incidentally, the processes for which the design operation has been completed this year, particularly the reaction process, coke separation process, SR recovery process, etc., are in the field untrodden technologically in the world; therefore, their design method is supposed to be established from the results of the R and D on coal liquefaction, '1 t/day class solvolysis coal liquefaction plant.' (NEDO)

  17. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Ji-Lu, E-mail: triace@163.com; Zhu, Ming-Qiang; Wu, Hai-tang

    2015-09-15

    Highlights: • Swine carcasses can be converted to bio-oil by alkaline hydrothermal liquefaction. • It seems that the use of the bio-oil for heat or CHP is technically suitable. • Some valuable chemicals were found in the bio-oils. • The bio-oil and the solid residue constituted an energy efficiency of 93.63% for the feedstock. • The solid residue can be used as a soil amendment, to sequester C and for preparing activated carbon. - Abstract: It is imperative that swine carcasses are disposed of safely, practically and economically. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil was performed. Firstly, the effects of temperature, reaction time and pH value on the yield of each liquefaction product were determined. Secondly, liquefaction products, including bio-oil and solid residue, were characterized. Finally, the energy recovery ratio (ERR), which was defined as the energy of the resultant products compared to the energy input of the material, was investigated. Our experiment shows that reaction time had certain influence on the yield of liquefaction products, but temperature and pH value had bigger influence on the yield of liquefaction products. Yields of 62.2 wt% bio-oil, having a high heating value of 32.35 MJ/kg and a viscosity of 305cp, and 22 wt% solid residue were realized at a liquefaction temperature of 250 °C, a reaction time of 60 min and a pH value of 9.0. The bio-oil contained up to hundreds of different chemical components that may be classified according to functional groups. Typical compound classes in the bio-oil were hydrocarbons, organic acids, esters, ketones and heterocyclics. The energy recovery ratio (ERR) reached 93.63%. The bio-oil is expected to contribute to fossil fuel replacement in stationary applications, including boilers and furnaces, and upgrading processes for the bio-oil may be used to obtain liquid transport fuels.

  18. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil

    International Nuclear Information System (INIS)

    Zheng, Ji-Lu; Zhu, Ming-Qiang; Wu, Hai-tang

    2015-01-01

    Highlights: • Swine carcasses can be converted to bio-oil by alkaline hydrothermal liquefaction. • It seems that the use of the bio-oil for heat or CHP is technically suitable. • Some valuable chemicals were found in the bio-oils. • The bio-oil and the solid residue constituted an energy efficiency of 93.63% for the feedstock. • The solid residue can be used as a soil amendment, to sequester C and for preparing activated carbon. - Abstract: It is imperative that swine carcasses are disposed of safely, practically and economically. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil was performed. Firstly, the effects of temperature, reaction time and pH value on the yield of each liquefaction product were determined. Secondly, liquefaction products, including bio-oil and solid residue, were characterized. Finally, the energy recovery ratio (ERR), which was defined as the energy of the resultant products compared to the energy input of the material, was investigated. Our experiment shows that reaction time had certain influence on the yield of liquefaction products, but temperature and pH value had bigger influence on the yield of liquefaction products. Yields of 62.2 wt% bio-oil, having a high heating value of 32.35 MJ/kg and a viscosity of 305cp, and 22 wt% solid residue were realized at a liquefaction temperature of 250 °C, a reaction time of 60 min and a pH value of 9.0. The bio-oil contained up to hundreds of different chemical components that may be classified according to functional groups. Typical compound classes in the bio-oil were hydrocarbons, organic acids, esters, ketones and heterocyclics. The energy recovery ratio (ERR) reached 93.63%. The bio-oil is expected to contribute to fossil fuel replacement in stationary applications, including boilers and furnaces, and upgrading processes for the bio-oil may be used to obtain liquid transport fuels

  19. Structural integration of separation and reaction systems: I. Integration of stage-wise processes

    Directory of Open Access Journals (Sweden)

    Mitrović Milan

    2002-01-01

    Full Text Available The structural integration of separation processes, using multifunctional equipment, has been studied on four stage-wise liquid-liquid separations extraction, absorption, distillation, adsorption and on some combinations of these processes. It was shown for stage - wise processes that the ultimate aim of equipment integration is 3-way integration (by components by steps and by stages and that membrane multiphase contactors present concerning the equipment optimal solutions in many cases. First, by using partially integrated equipment and, later by developing fully integrated systems it was experimentally confirmed that structural 3-way integration produces much higher degrees of component separations and component enrichments in compact and safe equipment.

  20. GIS-based soil liquefaction susceptibility map of Mumbai city for earthquake events

    Science.gov (United States)

    Mhaske, Sumedh Yamaji; Choudhury, Deepankar

    2010-03-01

    The problem of liquefaction of soil during seismic event is one of the important topics in the field of Geotechnical Earthquake Engineering. Liquefaction of soil is generally occurs in loose cohesionless saturated soil when pore water pressure increases suddenly due to induced ground motion and shear strength of soil decreases to zero and leading the structure situated above to undergo a large settlement, or failure. The failures took place due to liquefaction induced soil movement spread over few square km area continuously. Hence this is a problem where spatial variation involves and to represent this spatial variation Geographic Information System (GIS) is very useful in decision making about the area subjected to liquefaction. In this paper, GIS software GRAM++ is used to prepare soil liquefaction susceptibility map for entire Mumbai city in India by marking three zones viz. critically liquefiable soil, moderately liquefiable soil and non liquefiable soil. Extensive field borehole test data for groundwater depth, standard penetration test (SPT) blow counts, dry density, wet density and specific gravity, etc. have been collected from different parts of Mumbai. Simplified procedure of Youd et al. (2001) is used for calculation of factor of safety against soil liquefaction potential. Mumbai city and suburban area are formed by reclaiming lands around seven islands since 1865 till current date and still it is progressing in the area such as Navi Mumbai and beyond Borivali to Mira road suburban area. The factors of safety against soil liquefaction were determined for earthquake moment magnitude ranging from Mw = 5.0 to 7.5. It is found that the areas like Borivali, Malad, Dahisar, Bhandup may prone to liquefaction for earthquake moment magnitude ranging from Mw = 5.0 to 7.5. The liquefaction susceptibility maps were created by using GRAM++ by showing the areas where the factor of safety against the soil liquefaction is less than one. Proposed liquefaction

  1. Novel bimetallic dispersed catalysts for temperature-programmed coal liquefaction. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chunshan Song; Schobert, H.H.; Parfitt, D.P. [and others

    1997-11-01

    Development of new catalysts is a promising approach to more efficient coal liquefaction. It has been recognized that dispersed catalysts are superior to supported catalysts for primary liquefaction of coals, because the control of initial coal dissolution or depolymerization requires intimate contact between the catalyst and coal. This research is a fundamental and exploratory study on catalytic coal liquefaction, with the emphasis on exploring novel bimetallic dispersed catalysts for coal liquefaction and the effectiveness of temperature-programmed liquefaction using dispersed catalysts. The primary objective of this research was to explore novel bimetallic dispersed catalysts from organometallic molecular precursors, that could be used in low concentrations but exhibit relatively high activity for efficient hydroliquefaction of coals under temperature-programmed conditions. We have synthesized and tested various catalyst precursors in liquefaction of subbituminous and bituminous coals and in model compound studies to examine how do the composition and structure of the catalytic precursors affect their effectiveness for coal liquefaction under different reaction conditions, and how do these factors affect their catalytic functions for hydrogenation of polyaromatic hydrocarbons, for cleavage of C-C bonds in polycyclic systems such as 4-(1-naphthylmethyl)bibenzyl, for hydrogenolysis of C-O bond such as that in dinaphthylether, for hydrodeoxygenation of phenolic compounds and other oxygen-containing compounds such as xanthene, and for hydrodesulfurization of polycyclic sulfur compounds such as dibenzothiophene. The novel bimetallic and monometallic precursors synthesized and tested in this project include various Mo- and Fe-based compounds.

  2. Report on the coal liquefaction committee in fiscal 1992; 1992 nendo sekitan ekika iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-03-01

    This paper reports the activities of the coal liquefaction committee in fiscal 1992. The first committee meeting was held on August 21. After having confirmed the minutes of the previous meeting, an explanation was given on the research and development plans in fiscal 1992. The explanation covered the general explanation, bituminous coal liquefaction, brown coal liquefaction, and the common and fundamental aspects. The presented topics included the achievements in the operations using a bituminous coal liquefaction PSU and a small device, the status of compiling the achievements in the brown coal liquefaction project, preparation of the basic policy on developing the common basic technologies, and structuring of a coal liquefaction technology package. The second meeting was held on March 18, 1993. The meeting verified the minutes of the previous meeting, and gave the sub-committee reports for fiscal 1992. The sub-committees include those for bituminous coal liquefaction, brown coal liquefaction, environmental safety evaluation, and separation and refining technologies. As the summary of the achievements in fiscal 1992, descriptions were given on the bituminous coal liquefaction, brown coal liquefaction, and common and basic aspects. The fiscal 1993 plan presented included the budget aspect. A description was given as a topic on the economic performance evaluation and the working scheme (the execution plan) for the brown coal liquefaction process. (NEDO)

  3. Liquefaction of ground tire rubber at low temperature.

    Science.gov (United States)

    Cheng, Xiangyun; Song, Pan; Zhao, Xinyu; Peng, Zonglin; Wang, Shifeng

    2018-01-01

    Low-temperature liquefaction has been investigated as a novel method for recycling ground tire rubber (GTR) into liquid using an environmentally benign process. The liquefaction was carried out at different temperatures (140, 160 and 180 °C) over variable time ranges (2-24 h) by blending the GTR with aromatic oil in a range from 0 to 100 parts per hundred rubber (phr). The liquefied GTR was separated into sol (the soluble fraction of rubber which can be extracted with toluene) and gel fractions (the solid fraction obtained after extraction) to evaluate the reclaiming efficiency. It was discovered that the percentage of the sol fraction increased with time, swelling ratio and temperature. Liquefied rubber was obtained with a high sol fraction (68.34 wt%) at 140 °C. Simultaneously, separation of nano-sized carbon black from the rubber networks occurred. The separation of carbon black from the network is the result of significant damage to the cross-linked-network that occurs throughout the liquefaction process. During liquefaction, a competitive reaction between main chain scission and cross-link bond breakage takes place. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Japan's New Sunshine Project. 1994 annual summary of coal liquefaction and gasification

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This paper summarizes the report for fiscal 1994 on research and development related to coal liquefaction and gasification. In the research and development of coal liquefaction technologies, reports were given on research of liquefaction characteristics of different coals and liquefaction process thereof, and on research of catalysts for the coal liquefaction. In the research and development of coal gasification technologies, reports were given on fundamental studies on gasification characteristics of different coals. In the research and development of liquefaction technologies for bituminous coal, reports were given on design, construction and operation of a bituminous coal liquefaction pilot plant with a capacity of 150 t/d, and the operation supporting studies on the pilot plant. In the fundamental research on the coal liquefaction process, reports were given on refining technologies and utilization of the refined materials, and studies on environment preservation in applying the coal liquefaction technologies. In the research on hydrogen manufacturing technologies by using the fundamental coal technology, reports were given on design, construction and operational studies of a pilot plant. In the research and development of the coal gasification technologies, reports were given on development of a jet-flow gasified coal electric power plant, selection of coals, and development of a data processing system. (NEDO)

  5. Engineering geologic and geotechnical analysis of paleoseismic shaking using liquefaction effects: Field examples

    Science.gov (United States)

    Green, R.A.; Obermeier, S.F.; Olson, S.M.

    2005-01-01

    The greatest impediments to the widespread acceptance of back-calculated ground motion characteristics from paleoliquefaction studies typically stem from three uncertainties: (1) the significance of changes in the geotechnical properties of post-liquefied sediments (e.g., "aging" and density changes), (2) the selection of appropriate geotechnical soil indices from individual paleoliquefaction sites, and (3) the methodology for integration of back-calculated results of strength of shaking from individual paleoliquefaction sites into a regional assessment of paleoseismic strength of shaking. Presented herein are two case studies that illustrate the methods outlined by Olson et al. [Engineering Geology, this issue] for addressing these uncertainties. The first case study is for a site near Memphis, Tennessee, wherein cone penetration test data from side-by-side locations, one of liquefaction and the other of no liquefaction, are used to readily discern that the influence of post-liquefaction "aging" and density changes on the measured in situ soil indices is minimal. In the second case study, 12 sites that are at scattered locations in the Wabash Valley and that exhibit paleoliquefaction features are analyzed. The features are first provisionally attributed to the Vincennes Earthquake, which occurred around 6100 years BP, and are used to illustrate our proposed approach for selecting representative soil indices of the liquefied sediments. These indices are used in back-calculating the strength of shaking at the individual sites, the results from which are then incorporated into a regional assessment of the moment magnitude, M, of the Vincennes Earthquake. The regional assessment validated the provisional assumption that the paleoliquefaction features at the scattered sites were induced by the Vincennes Earthquake, in the main, which was determined to have M ??? 7.5. The uncertainties and assumptions used in the assessment are discussed in detail. ?? 2004 Elsevier B

  6. Post-liquefaction soil-structure interaction for buried structures: Sensitivity analysis studies

    International Nuclear Information System (INIS)

    Pires, J.A.; Ang, H.S.; Katayama, I.; Satoh, M.

    1993-01-01

    The post liquefaction behavior of buried conduits is analyzed and sensitivity analysis is conducted to investigate the damage potential of the forces induced in the buried lifelines following seismically induced liquefaction of the surrounding soil. Various lifeline configurations and loading conditions are considered. The loading conditions considered are: buoyancy forces and permanent ground displacements parallel to the lifeline axis. Pertinent parameters for the soil-lifeline interaction following liquefaction are identified. (author)

  7. Cooperative research in coal liquefaction. Technical progress report, May 1, 1993--April 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Huffman, G.P. [ed.

    1994-10-01

    Accomplishments for the past year are presented for the following tasks: coliquefaction of coal with waste materials; catalysts for coal liquefaction to clean transportation fuels; fundamental research in coal liquefaction; and in situ analytical techniques for coal liquefaction and coal liquefaction catalysts some of the highlights are: very promising results have been obtained from the liquefaction of plastics, rubber tires, paper and other wastes, and the coliquefaction of wastes with coal; a number of water soluble coal liquefaction catalysts, iron, cobalt, nickel and molybdenum, have been comparatively tested; mossbauer spectroscopy, XAFS spectroscopy, TEM and XPS have been used to characterize a variety of catalysts and other samples from numerous consortium and DOE liquefaction projects and in situ ESR measurements of the free radical density have been conducted at temperatures from 100 to 600{degrees}C and H{sub 2} pressures up to 600 psi.

  8. Sinking during earthquakes: Critical acceleration criteria control drained soil liquefaction

    Science.gov (United States)

    Clément, C.; Toussaint, R.; Stojanova, M.; Aharonov, E.

    2018-02-01

    This article focuses on liquefaction of saturated granular soils, triggered by earthquakes. Liquefaction is defined here as the transition from a rigid state, in which the granular soil layer supports structures placed on its surface, to a fluidlike state, in which structures placed initially on the surface sink to their isostatic depth within the granular layer. We suggest a simple theoretical model for soil liquefaction and show that buoyancy caused by the presence of water inside a granular medium has a dramatic influence on the stability of an intruder resting at the surface of the medium. We confirm this hypothesis by comparison with laboratory experiments and discrete-element numerical simulations. The external excitation representing ground motion during earthquakes is simulated via horizontal sinusoidal oscillations of controlled frequency and amplitude. In the experiments, we use particles only slightly denser than water, which as predicted theoretically increases the effect of liquefaction and allows clear depth-of-sinking measurements. In the simulations, a micromechanical model simulates grains using molecular dynamics with friction between neighbors. The effect of the fluid is captured by taking into account buoyancy effects on the grains when they are immersed. We show that the motion of an intruder inside a granular medium is mainly dependent on the peak acceleration of the ground motion and establish a phase diagram for the conditions under which liquefaction happens, depending on the soil bulk density, friction properties, presence of water, and peak acceleration of the imposed large-scale soil vibrations. We establish that in liquefaction conditions, most cases relax toward an equilibrium position following an exponential in time. We also show that the equilibrium position itself, for most liquefaction regimes, corresponds to the isostatic equilibrium of the intruder inside a medium of effective density. The characteristic time to relaxation is

  9. Liquefaction under drained condition, from the lab to reality ?

    Science.gov (United States)

    Clément, Cécile; Aharonov, Einat; Stojanova, Menka; Toussaint, Renaud

    2015-04-01

    Liquefaction constitutes a significant natural hazard in relation to earthquakes and landslides. This effect can cause buildings to tilt or sink into the soil, mud-volcanoes, floatation of buried objects, long-runout landslides, etc. In this work we present a new understanding regarding the mechanism by which buildings sink and tilt during liquefaction caused by earthquakes. Conventional understanding of liquefaction explains most observed cases as occurring in an undrained, under-compacted, layer of sandy soil saturated with water [1]: According to that understanding, the under compacted sandy layer has the tendency to compact when a load is applied. In our case the load comes from ground shaking during an earthquake. When the soil compacts, the fluid pore pressure rises. Because in undrained conditions the fluid cannot flow out, the pore pressure builds up. The weight of buildings is in this case transferred from the grains of the soil to the pore water. The soil loses its rigidity and it flows like a liquid. From this model scientists made theoretical and empirical laws for geotechnical use and buildings construction. Despite the success of this conventional model in many cases, liquefied soils were also observed under drained conditions, and in previously compacted soils, which doesn't agree with the assumption of the model quoted above. One of the famous liquefaction events is the Kobe port destruction during the 1995 earthquake. A simple calculation of the Deborah number following Goren et al ([2][3]) shows that the undrained constraint was not met below the Kobe port during the 1995 earthquake. We propose another model, of liquefaction in drained granular media. According to our model the mere presence of water in granular media is enough to cause liquefaction during an earthquake, provided that the water reaches close to the surface. Our computations are based on the buoyancy force, and we take into account the static fluid pressure only. For small

  10. Preliminary study of soil liquefaction hazard at Terengganu shoreline, Peninsular Malaysia

    Science.gov (United States)

    Hashim, H.; Suhatril, M.; Hashim, R.

    2017-06-01

    Terengganu is a shoreline state located in Peninsular Malaysia which is a growing hub for port industries and tourism centre. The northern part offers pristine settings of a relax beach areas whereas the southern part are observed to be a growing centre for development. The serious erosion on soil deposit along the beach line presents vulnerable soil condition to soil liquefaction consists of sandy with low plasticity and shallow ground water. Moreover, local earthquake from nearby fault have present significant tremors over the past few years which need to be considered in the land usage or future development in catering the seismic loading. Liquefaction analysis based on field standard penetration of soil is applied on 546 boreholes scattered along the shoreline areas ranging 244 km of shoreline stretch. Based on simplified approach, it is found that more than 70% of the studied areas pose high liquefaction potential since there are saturated loose sand and silt deposits layer ranges at depth 3 m and up to 20 m. The presence of clay deposits and hard stratum at the remaining 30% of the studied areas shows good resistance to soil liquefaction hence making the area less significant to liquefaction hazard. Result indicates that liquefaction improving technique is advisable in future development of shoreline areas of Terengganu state.

  11. Biomass Indirect Liquefaction Strategy Workshop Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-07-01

    This report is based on the proceedings of the U.S. Department of Energy Bioenergy Technologies Office Biomass Indirect Liquefaction Strategy Workshop. The workshop, held March 20–21, 2014, in Golden, Colorado, discussed and detailed the research and development needs for biomass indirect liquefaction. Discussions focused on pathways that convert biomass-based syngas (or any carbon monoxide, hydrogen gaseous stream) to liquid intermediates (alcohols or acids) and further synthesize those intermediates to liquid hydrocarbons that are compatible as either a refinery feed or neat fuel.

  12. Meta-analysis of Gaussian individual patient data: Two-stage or not two-stage?

    Science.gov (United States)

    Morris, Tim P; Fisher, David J; Kenward, Michael G; Carpenter, James R

    2018-04-30

    Quantitative evidence synthesis through meta-analysis is central to evidence-based medicine. For well-documented reasons, the meta-analysis of individual patient data is held in higher regard than aggregate data. With access to individual patient data, the analysis is not restricted to a "two-stage" approach (combining estimates and standard errors) but can estimate parameters of interest by fitting a single model to all of the data, a so-called "one-stage" analysis. There has been debate about the merits of one- and two-stage analysis. Arguments for one-stage analysis have typically noted that a wider range of models can be fitted and overall estimates may be more precise. The two-stage side has emphasised that the models that can be fitted in two stages are sufficient to answer the relevant questions, with less scope for mistakes because there are fewer modelling choices to be made in the two-stage approach. For Gaussian data, we consider the statistical arguments for flexibility and precision in small-sample settings. Regarding flexibility, several of the models that can be fitted only in one stage may not be of serious interest to most meta-analysis practitioners. Regarding precision, we consider fixed- and random-effects meta-analysis and see that, for a model making certain assumptions, the number of stages used to fit this model is irrelevant; the precision will be approximately equal. Meta-analysts should choose modelling assumptions carefully. Sometimes relevant models can only be fitted in one stage. Otherwise, meta-analysts are free to use whichever procedure is most convenient to fit the identified model. © 2018 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

  13. Study on thermochemical liquefaction of biomass feedstocks; Biomass genryo no yuka hanno tokusei ni kansuru kisoteki kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-10

    Liquefaction is applied to various biomass wastes and unused biomass to study characteristics of the liquefaction in each case. The paper described the system of the conversion and use of biomass into energy, conducted the positioning of the liquefaction, and outlined a history of the liquefaction chemistry and the study. To obtain basic data of characteristics of the liquefaction of various biomass raw materials, the liquefaction was conducted changing operational factors for the purpose of clarifying the product distribution of oil and by-products and oil properties. A comprehensive consideration was made of the liquefaction based on basic data and literature reports on the liquefaction of various biomass. From the above-mentioned studies, it was concluded that the energy can be recovered in a form of oil by applying the liquefaction to various biomass materials. A series of the study clarified effects of various operational factors on characteristics of the liquefaction as well as effects of classification of biomass materials and composition of the materials on characteristics of the liquefaction. 141 refs., 78 figs., 56 tabs.

  14. Liquefaction assessment based on combined use of CPT and shear wave velocity measurements

    Science.gov (United States)

    Bán, Zoltán; Mahler, András; Győri, Erzsébet

    2017-04-01

    Soil liquefaction is one of the most devastating secondary effects of earthquakes and can cause significant damage in built infrastructure. For this reason liquefaction hazard shall be considered in all regions where moderate-to-high seismic activity encounters with saturated, loose, granular soil deposits. Several approaches exist to take into account this hazard, from which the in-situ test based empirical methods are the most commonly used in practice. These methods are generally based on the results of CPT, SPT or shear wave velocity measurements. In more complex or high risk projects CPT and VS measurement are often performed at the same location commonly in the form of seismic CPT. Furthermore, VS profile determined by surface wave methods can also supplement the standard CPT measurement. However, combined use of both in-situ indices in one single empirical method is limited. For this reason, the goal of this research was to develop such an empirical method within the framework of simplified empirical procedures where the results of CPT and VS measurements are used in parallel and can supplement each other. The combination of two in-situ indices, a small strain property measurement with a large strain measurement, can reduce uncertainty of empirical methods. In the first step by careful reviewing of the already existing liquefaction case history databases, sites were selected where the records of both CPT and VS measurement are available. After implementing the necessary corrections on the gathered 98 case histories with respect to fines content, overburden pressure and magnitude, a logistic regression was performed to obtain the probability contours of liquefaction occurrence. Logistic regression is often used to explore the relationship between a binary response and a set of explanatory variables. The occurrence or absence of liquefaction can be considered as binary outcome and the equivalent clean sand value of normalized overburden corrected cone tip

  15. Optimisation of expansion liquefaction processes using mixed refrigerant N_2–CH_4

    International Nuclear Information System (INIS)

    Ding, He; Sun, Heng; He, Ming

    2016-01-01

    Highlights: • A refrigerant composition matching method for N_2–CH_4 expansion processes. • Efficiency improvements for propane pre-cooled N_2–CH_4 expansion processes. • The process shows good adaptability to varying natural gas compositions. - Abstract: An expansion process with a pre-cooling system is simulated and optimised by Aspen HYSYS and MATLAB"™. Taking advantage of higher specific refrigeration effect of methane and easily reduced refrigeration temperature of nitrogen, the designed process adopts N_2–CH_4 as a mixed refrigerant. Based on the different thermodynamic properties and sensitivity difference of N_2 and CH_4 over the same heat transfer temperature range, this work proposes a novel method of matching refrigerant composition which aims at single-stage or multi-stage series expansion liquefaction processes with pre-cooling systems. This novel method is applied successfully in propane pre-cooled N_2–CH_4 expansion process, and the unit power consumption is reduced to 7.09 kWh/kmol, which is only 5.35% higher than the global optimised solutions obtained by genetic algorithm. This novel method can fulfil the accomplishments of low energy consumption and high liquefaction rate, and thus decreases the gap between the mixed refrigerant and expansion processes in energy consumption. Furthermore, the high exergy efficiency of the process indicates good adaptability to varying natural gas compositions.

  16. Effect of Recycle Solvent Hydrotreatment on Oil Yield of Direct Coal Liquefaction

    Directory of Open Access Journals (Sweden)

    Shansong Gao

    2015-07-01

    Full Text Available Effects of the recycle solvent hydrotreatment on oil yield of direct coal liquefaction were carried out in the 0.18 t/day direct coal liquefaction bench support unit of National Engineering Laboratory for Direct Coal Liquefaction (China. Results showed that the hydrogen-donating ability of the hydrogenated recycle solvent improved and the hydrogen consumption of solvent hydrotreatment was increased by decreasing liquid hourly space velocity (LHSV from 1.5 to 1.0 h−1 and increasing reaction pressure from 13.7 to 19.0 MPa. The hydrogen-donating ability of the hydrogenated recycle solvent was enhanced, thus promoting the oil yield and coal conversion of the liquefaction reaction. The coal conversion and distillates yield of coal liquefaction were increased from 88.74% to 88.82% and from 47.41% to 49.10%, respectively, with the increase in the solvent hydrotreatment pressure from 13.7 to 19.0 MPa. The coal conversion and distillates of coal liquefaction were increased from 88.82% to 89.27% and from 49.10% to 54.49%, respectively, when the LHSV decreased from 1.5 to 1.0 h−1 under the solvent hydrotreatment pressure of 19.0 MPa.

  17. Dynamic behavior of potentially unstable soils and application of model for seismic risk reduction from liquefaction occurrence

    International Nuclear Information System (INIS)

    Sheshov, Vlatko

    2002-11-01

    Throughout the last decades, liquefaction phenomenon has been one of the most frequently discussed subjects in geotechnical earthquake engineering. Liquefaction has been a problem arousing considerable attention among the world scientists. The consequences from liquefaction occurrence have been present after each stronger earthquake. We have been witnesses of several strong earthquakes (Kobe - Japan, Chi Chi-Taiwan, Bhuj-India) that have occurred in the last decade. In these earthquakes, the liquefaction phenomenon caused severe damage to structures, loss of their functioning and indirect loss of human lives. Liquefaction as a phenomenon should not arouse fear but should call for serious elaboration and attention instead. The destructive nature of liquefaction could be mitigated, i.e., overcome in two ways: avoiding construction at locations characterized by high liquefaction potential which is not always possible and taking of measures for improvement of foundation soil. Finding out suitable measures for improvement of soil and thus mitigating the liquefaction potential has been the main incentive for the elaboration of this dissertation. The dissipation method involving the use of vertical drains as one of the measures for improvement of soils has been elaborated in details in this scientific work. The doctoral dissertation has been realized through experimental and analytical investigations. The experimental investigations done in the first phase represent model seismic shaking table tests of the efficiency of vertical drains (prefabricated and gravel drains). The analytical investigations in this phase have involved mathematical simulation of the effect of vertical drains upon pore pressure state during the experiments. The second phase of the experimental investigations has involved model tests of the behavior of pile foundations in soils susceptible to liquefaction with installed prefabricated drains. In this phase, the 'p - y' relationships have been

  18. Optimization for microwave-assisted direct liquefaction of bamboo residue in glycerol/methanol mixtures

    Science.gov (United States)

    Jiulong Xie; Jinqiu Qi; Chungyun Hse; Todd F. Shupe

    2015-01-01

    Bamboo residues were liquefied in a mixture of glycerol and methanol in the presence of sulfuric acid using microwave energy. We investigated the effects of liquefaction conditions, including glycerol/methanol ratio, liquefaction temperature, and reaction time on the conversion yield. The optimal liquefaction conditions were under the temperature of 120

  19. Characteristics estimation of coal liquefaction residue; Sekitan ekika zansa seijo no suisan ni kansuru kento

    Energy Technology Data Exchange (ETDEWEB)

    Itonaga, M.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Okada, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan)

    1996-10-28

    The paper studied a possibility of estimating characteristics of coal liquefaction residue from liquefaction conditions in the case of fixing coal kind in the NEDOL process coal liquefaction PSU. Wyoming coal was used for the study, and the already proposed simplified liquefaction reaction models were used. Among material balances explained by the models, those of asphaltene, preasphaltene, THF insoluble matters are concerned with residue composition. Ash content is separately calculated from ash balance. Reaction velocity constants of simplified liquefaction reaction models which influence the residue composition were obtained by the multiple regression method from experimental results in the past. The estimation expression of residue viscosity was introduced from residue ash/composition. When the residue composition is estimated by the model from liquefaction conditions, and the residue viscosity is obtained using it, the higher the liquefaction temperature is, the higher the residue viscosity is. The result obtained well agreed the measuring result. The simplified liquefaction model of a certain coal kind has been established, and characteristics of residue can be estimated even at liquefaction conditions which have never been experienced before if there is a certain amount of the accumulated data on residue composition/characteristics. 4 refs., 4 figs., 4 tabs.

  20. Liquefaction behaviors of bamboo residues in a glycerol-based solvent using microwave energy

    Science.gov (United States)

    Jiulong Xie; Chung-Yun Hse; Todd F. Shupe; Jinqiu Qi; Hui Pan

    2014-01-01

    Liquefaction of bamboo was performed in glycerol–methanol as co-solvent using microwave energy and was evaluated by characterizing the liquefied residues. High efficiency conversion of bamboo was achieved under mild reaction conditions. Liquefaction temperature and time interacted to affect the liquefaction reaction. Fourier transform infrared analyzes of the residues...

  1. Influence of solvent type on microwave-assisted liquefaction of bamboo

    Science.gov (United States)

    Jiulong Xie; Chung Hse; Todd F. Shupe; Tingxing Hu

    2016-01-01

    Microwave-assisted liquefaction of bamboo in glycerol, polyethylene glycerol (PEG), methanol, ethanol, and water were comparatively investigated by evaluating the temperature-dependence for conversion and liquefied residue characteristics. The conversion for the liquefaction in methanol, ethanol, and water increased with an increase in reaction temperature, while that...

  2. An optimum cold end configuration for helium liquefaction cycles

    International Nuclear Information System (INIS)

    Minta, M.; Smith, J.L.

    1984-01-01

    This chapter examines the effect of the non-ideal behavior of helium at low temperature on the performance of helium liquefaction cycles. The effect is isolated by means of a continuum model for the precooling stage. The cold end losses are due primarily to the composite effect of the non-ideality of helium at low temperatures and the heat exchanger losses, in addition to the component losses fixed by the expander/compressor efficiencies. Topics considered include continuously distributed full-pressure ratio expanders, continuously distributed full-flow expanders, the heat exchange effect (ideal gas working fluid, real gas working fluid), and cold end configuration. The cold end configuration minimizes the cycle cold end losses

  3. Characteristics of the products of hydrothermal liquefaction combined with cellulosic bio-ethanol process

    International Nuclear Information System (INIS)

    Li, Rundong; Xie, Yinghui; Yang, Tianhua; Li, Bingshuo; Zhang, Yang; Kai, Xingping

    2016-01-01

    The integration utilization of fermentation residues from cellulosic bio-ethanol has attracted a great deal of attention to balance the total cost of bio-ethanol production while simultaneously dealing with bio-ethanol wastewater. A process of hydrothermal liquefaction (HTL) of intact materials from cellulosic bio-ethanol in a batch reactor was proposed. The effects of the reaction temperature and time on the liquefaction characteristics were examined. The optimum condition for liquefaction fermentation residues was 370 °C (21.25 MPa) and 30 min with a bio-oil yield of 40.79 wt%. GC-MS results indicated that the major chemical species in the bio-oil were phenols, ketones, long-chain hydrocarbons and fatty acids. Supercritical conditions (375 °C, 23.50 MPa) was favored for the low-molecular-weight species formation compared to subcritical conditions (370 °C, 21.25 MPa), as some long-chain species decreased. This work thus can provide a novel idea for bio-oil production from HTL of cellulosic bio-ethanol fermentation residues. - Highlights: • Bio-oil production via HTL combined with cellulosic bio-ethanol process was proposed. • Optimum condition for HTL of materials from cellulosic bio-ethanol was 370 °C and 30 min. • Bio-oil contained higher content of hydrocarbons and lower contents of organic acids.

  4. Comparative study on liquefaction of creosote and chromated copper arsenate (CCA)-treated wood and untreated southern pine wood: effects of acid catalyst content, liquefaction time, temperature, and phenol to wood ratio

    Science.gov (United States)

    Hui Pan; Chung-Yun Hse; Todd F. Shupe

    2009-01-01

    Creosote- and chromated copper arsenate (CCA)-treated wood waste and untreated southern pine wood were liquefied with phenol and sulfuric acid. The effects of sulfuric acid content, liquefaction time, liquefaction temperature, and phenol to wood ratio on liquefaction rate (i.e., wood residue content) were investigated and analyzed by analysis of variance (...

  5. Hydrothermal liquefaction of agricultural and forestry wastes: state-of-the-art review and future prospects.

    Science.gov (United States)

    Cao, Leichang; Zhang, Cheng; Chen, Huihui; Tsang, Daniel C W; Luo, Gang; Zhang, Shicheng; Chen, Jianmin

    2017-12-01

    Hydrothermal liquefaction has been widely applied to obtain bioenergy and high-value chemicals from biomass in the presence of a solvent at moderate to high temperature (200-550°C) and pressure (5-25MPa). This article summarizes and discusses the conversion of agricultural and forestry wastes by hydrothermal liquefaction. The history and development of hydrothermal liquefaction technology for lignocellulosic biomass are briefly introduced. The research status in hydrothermal liquefaction of agricultural and forestry wastes is critically reviewed, particularly for the effects of liquefaction conditions on bio-oil yield and the decomposition mechanisms of main components in biomass. The limitations of hydrothermal liquefaction of agricultural and forestry wastes are discussed, and future research priorities are proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Liquefaction technology assessment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-05-01

    A survey of coal liquefaction technology and analysis of projected relative performance of high potential candidates has been completed and the results are reported here. The key objectives of the study included preparation of a broad survey of the status of liquefaction processes under development, selection of a limited number of high potential process candidates for further study, and an analysis of the relative commercial potential of these candidates. Procedures which contributed to the achievement of the above key goals included definition of the characteristics and development status of known major liquefaction process candidates, development of standardized procedures for assessing technical, environmental, economic and product characteristics for the separate candidates, and development of procedures for selecting and comparing high potential processes. The comparisons were made for three production areas and four marketing areas of the US. In view of the broad scope of the objectives the survey was a limited effort. It used the experience gained during preparation of seven comprehensive conceptual designs/economic evaluations plus comprehensive reviews of the designs, construction and operation of several pilot plants. Results and conclusions must be viewed in the perspective of the information available, how this information was treated, and the full context of the economic comparison results. Comparative economics are presented as ratios; they are not intended to be predictors of absolute values. Because the true cost of constructing and operating large coal conversion facilities will be known only after commercialization, relative values are considered more appropriate. (LTN)

  7. Liquefaction induced by modern earthquakes as a key to paleoseismicity: A case study of the 1988 Saguenay event

    International Nuclear Information System (INIS)

    Tuttle, M.; Cowie, P.; Wolf, L.

    1992-01-01

    Liquefaction features, including sand dikes, sills, and sand-filled craters, that formed at different distances from the epicenter of the 1988 (Mw 5.9) Saguenay earthquake are compared with one another and with older features. Modern liquefaction features decrease in size with increasing distance from the Saguenay epicenter. This relationship suggests that the size of liquefaction features may be used to determine source zones of past earthquakes and to estimate attenuation of seismic energy. Pre-1988 liquefaction features are cross-cut by the 1988 features. Although similar in morphology to the modern features, the pre-1988 features are more weathered and considerably larger in size. The larger pre-1988 features are located in the Ferland area, whereas the smallest pre-1988 feature occurs more than 37 km to the southwest. This spatial distribution of different size features suggests that an unidentified earthquake source zone (in addition to the one that generated the Saguenay earthquake) may exist in the Laurentide-Saguenay region. Structural relationships of the liquefaction features indicate that one, possibly two, earthquakes induced liquefaction in the region prior to 1988. The age of only one pre-1988 feature is well-constrained at 340 ± 70 radiocarbon years BP. If the 1663 earthquake was responsible for the formation of this feature, this event may have been centered in the Laurentide-Saguenay region rather than in the Charlevoix seismic zone

  8. Hydrogen Transfer during Liquefaction of Elbistan Lignite to Biomass; Total Reaction Transformation Approach

    Science.gov (United States)

    Koyunoglu, Cemil; Karaca, Hüseyin

    2017-12-01

    Given the high cost of the tetraline solvent commonly used in liquefaction, the use of manure with EL is an important factor when considering the high cost of using tetraline as a hydrogen transfer source. In addition, due to the another cost factor which is the catalyst prices, red mud (commonly used, produced as a byproduct in the production of aluminium) is reduced cost in the work of liquefaction of coal, biomass, even coal combined biomass, corresponding that making the EL liquefaction an agenda for our country is another important factor. Conditions for liquefaction experiments conducted for hydrogen transfer from manure to coal; Catalyst concentration of 9%, liquid/solid ratio of 3/1, reaction time of 60 min, fertilizer/lignite ratio of 1/3, and the reaction temperature of 400 °C, the stirred speed of 400 rpm and the initial nitrogen pressure of 20 bar was fixed. In order to demonstrate the hydrogen, transfer from manure to coal, coal is used solely, by using tetraline (also known as a hydrogen carrier) and distilled water which is not hydrogen donor as a solvent in the co-liquefaction of experiments, and also the liquefaction conditions are carried out under an inert (N2) gas atmosphere. According to the results of the obtained liquefaction test; using tetraline solvent the total liquid product conversion percentage of the oil + gas conversion was 38.3 %, however, the results of oil+gas conversion obtained using distilled water and EL combined with manure the total liquid product conversion percentage was 7.4 %. According to the results of calorific value and elemental analysis, only the ratio of (H/C)atomic of coal obtained by using tetraline increased with the liquefaction of manure and distilled water. The reason of the increase in the amount of hydrogen due to hydrogen transfer from the manure on the solid surface of the coal, and also on the surface of the inner pore of the coal during the liquefaction, brings about the evaluation of the coal as a

  9. Production of Advanced Biofuels via Liquefaction - Hydrothermal Liquefaction Reactor Design: April 5, 2013

    Energy Technology Data Exchange (ETDEWEB)

    Knorr, D.; Lukas, J.; Schoen, P.

    2013-11-01

    This report provides detailed reactor designs and capital costs, and operating cost estimates for the hydrothermal liquefaction reactor system, used for biomass-to-biofuels conversion, under development at Pacific Northwest National Laboratory. Five cases were developed and the costs associated with all cases ranged from $22 MM/year - $47 MM/year.

  10. Studies on catalytic hydrotreating of recycled solvents from coal liquefaction process. Part 1. Characteristics changes of recycled solvents during hydrotreating

    Energy Technology Data Exchange (ETDEWEB)

    Morimura, Y.; Nakata, S.; Yokota, Y.; Shirota, Y.; Nakamura, M. [Chiyoda Corp., Tokyo (Japan); Mitarai, Y. [Sumitomo Metal Mining Co. Ltd., Tokyo (Japan); Inoue, Y. [Nippon Ketjen Co. Ltd., Tokyo (Japan)

    1995-07-01

    A bituminous coal liquefaction process, called the NEDOL process, is under development by the New Energy and Industrial Technology Development Organization (NEDO). Important features of this process include the capacity to produce hydrogen-donatable solvents, obtained by hydrogenation of middle distillates of coal derived oils, and to recycle these solvents to a liquefaction stage as hydrogen donor solvents. These recycled solvents, obtained by liquefaction of Wandoan coal, and their catalytic hydrotreated oils, have been extensively characterized, using a variety of analytical methods. The following items have been examined and are discussed in this study: (1) Influence of chemical hydrogen consumption on the reactivities of hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodeoxygenation (HDO) and hydrogenation of aromatic-rings, during hydrotreating; (2) Changes in composition of hydrocarbon types, nitrogen- and oxygen-containing compounds, as a function of chemical hydrogen consumption; (3) Changes of average molecular weights; (4) Characteristics changes of oxygen- and nitrogen-containing compounds, and reactivities of HDO and HDN; (5) Characteristics changes of donatable hydrogen as a function of a degree of hydrogenation ({delta}fa). 14 refs., 14 figs., 3 tabs.

  11. Numerical modeling of liquefaction-induced failure of geo-structures subjected to earthquakes

    International Nuclear Information System (INIS)

    Rapti, Ioanna

    2016-01-01

    and coupled hydro-mechanical conditions. Two criteria are used to define the onset of the structure's collapse. The second order work is used to describe the local instability at specific instants of the ground motion, while the estimation of a local safety factor is proposed by calculating soil's residual strength. Concerning the failure mode, the effect of excess pore water pressure is of great importance, as an otherwise stable structure-foundation system in dry and fully drained conditions becomes unstable during coupled analysis. Finally, a levee-foundation system is simulated and the influence of soil's permeability, depth of the liquefiable layer, as well as, characteristics of input ground motion on the liquefaction-induced failure is evaluated. For the current levee model, its induced damage level (i.e. settlements and deformations) is strongly related to both liquefaction apparition and dissipation of excess pore water pressure on the foundation. A circular collapse surface is generated inside the liquefied region and extends towards the crest in both sides of the levee. Even so, when the liquefied layer is situated in depth, no effect on the levee response is found. This research work can be considered as a reference case study for seismic assessment of embankment-type structures subjected to earthquake and provides a high-performance computational framework accessible to engineers. (author)

  12. One-stage and two-stage penile buccal mucosa urethroplasty

    Directory of Open Access Journals (Sweden)

    G. Barbagli

    2016-03-01

    Full Text Available The paper provides the reader with the detailed description of current techniques of one-stage and two-stage penile buccal mucosa urethroplasty. The paper provides the reader with the preoperative patient evaluation paying attention to the use of diagnostic tools. The one-stage penile urethroplasty using buccal mucosa graft with the application of glue is preliminary showed and discussed. Two-stage penile urethroplasty is then reported. A detailed description of first-stage urethroplasty according Johanson technique is reported. A second-stage urethroplasty using buccal mucosa graft and glue is presented. Finally postoperative course and follow-up are addressed.

  13. EARTHQUAKE INDUCED LIQUEFACTION ANALYSIS OF

    African Journals Online (AJOL)

    liquefaction analysis of Tendaho earth-fill dam, which is part ... sugar cane plantation in an area of 60,000 hectares. The project .... The model is prepared using the QUAKE/W program for the ..... Geo-slope International, Ltd., Canada. Dynamic ...

  14. Second stage gasifier in staged gasification and integrated process

    Science.gov (United States)

    Liu, Guohai; Vimalchand, Pannalal; Peng, Wan Wang

    2015-10-06

    A second stage gasification unit in a staged gasification integrated process flow scheme and operating methods are disclosed to gasify a wide range of low reactivity fuels. The inclusion of second stage gasification unit operating at high temperatures closer to ash fusion temperatures in the bed provides sufficient flexibility in unit configurations, operating conditions and methods to achieve an overall carbon conversion of over 95% for low reactivity materials such as bituminous and anthracite coals, petroleum residues and coke. The second stage gasification unit includes a stationary fluidized bed gasifier operating with a sufficiently turbulent bed of predefined inert bed material with lean char carbon content. The second stage gasifier fluidized bed is operated at relatively high temperatures up to 1400.degree. C. Steam and oxidant mixture can be injected to further increase the freeboard region operating temperature in the range of approximately from 50 to 100.degree. C. above the bed temperature.

  15. Assessment of Susceptibility to Liquefaction of Saturated Road Embankment Subjected to Dynamic Loads

    Science.gov (United States)

    Borowiec, Anna; Maciejewski, Krzysztof

    2014-03-01

    Liquefaction has always been intensely studied in parts of the world where earthquakes occur. However, the seismic activity is not the only possible cause of this phenomenon. It may in fact be triggered by some human activities, such as constructing and mining or by rail and road transport. In the paper a road embankment built across a shallow water reservoir is analyzed in terms of susceptibility to liquefaction. Two types of dynamic loadings are considered: first corresponding to an operation of a vibratory roller and second to an earthquake. In order to evaluate a susceptibility of soil to liquefaction, a factor of safety against triggering of liquefaction is used (FSTriggering). It is defined as a ratio of vertical effective stresses to the shear stresses both varying with time. For the structure considered both stresses are obtained using finite element method program, here Plaxis 2D. The plastic behavior of the cohesionless soils is modeled by means of Hardening Soil (HS) constitutive relationship, implemented in Plaxis software. As the stress tensor varies with time during dynamic excitation, the FSTriggering has to be calculated for some particular moment of time when liquefaction is most likely to occur. For the purposes of this paper it is named a critical time and established for reference point at which the pore pressures were traced in time. As a result a factor of safety distribution throughout embankment is generated. For the modeled structure, cyclic point loads (i.e., vibrating roller) present higher risk than earthquake of magnitude 5.4. Explanation why considered structure is less susceptible to earthquake than typical dam could lay in stabilizing and damping influence of water, acting here on both sides of the slope. Analogical procedure is applied to assess liquefaction susceptibility of the road embankment considered but under earthquake excitation. Only the higher water table is considered as it is the most unfavorable. Additionally the

  16. Co-liquefaction of micro algae with coal. 2; Bisai sorui to sekitan no kyoekika hanno. 2

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, C.; Matsui, T.; Otsuki, M.; Ikenaga, N.; Suzuki, T. [Kansai University, Osaka (Japan). Faculty of Engineering

    1996-10-28

    For the removal and recycle of CO2, a global warming gas, utilization of photosynthesis by micro algae is investigated. Formed micro algae are decomposed into CO2, H2O and CH4 again, which does not result in the permanent fixation. For the effective utilization of these micro algae, creation of petroleum alternate energy was tried through the co-liquefaction of micro algae with coal. Were investigated influences of the reaction temperature during the co-liquefaction and influences of catalysts, such as Fe(CO)5-S, Ru(CO)12, and Mo(CO)6-S, which are effective for the coal liquefaction. Micro algae, such as chlorella, spirulina, and littorale, and Yallourn brown coal were tested. It was found that co-liquefaction of micro algae with coal can be successfully proceeded under the same conditions as the liquefaction of coal. The oil yield obtained from the co-liquefaction in the presence of Fe(CO)5-S, an effective catalyst for coal liquefaction, agreed appropriately with the arithmetical mean value from separate liquefaction of coal and micro algae. It was suggested that pyrrhotite, an active species for coal liquefaction, was sufficiently formed by increasing the addition of sulfur. 2 refs., 7 figs., 1 tab.

  17. Liquefaction induced by earthquakes in Japan. Jiban no ekijoka/ekijoka saigai chosa kenkyu no seika

    Energy Technology Data Exchange (ETDEWEB)

    Tono, I [Nation Inst. for Enviromental Studies, Tsukuba (Japan)

    1992-09-01

    Disaster caused by liquefaction is an important problem for the development of water-front because most of the places suffered from liquefaction disasters recently are located on sandy grounds. The damaged cases in the past due to liquefaction induced by earthquakes are grouped into: subsidence and inclination caused by the loss of supporting force of the ground, coming to the surface of buried structures due to excess pore hydrostatic pressure, destruction of lifeline accompanying the fluidization of ground, breakdown of bulkhead, retaining wall, etc. by increased earth pressure, sinking of soil structures, ground fissure, sliding, and immersion in floods and submergence of farms due to spouting of underground water. As regards prediction of liquefaction, description is made on the prediction of the occurrence of liquefaction and liquefaction prediction for which sedimentation environment is taken into consideration. Open-cut investigation can be said as the most effective means for accurate learning of the depth, thickness and sedimentation structure of liquefied layers. Liquefaction layers found in remains are also introduced. 16 refs., 6 figs.

  18. Thermodynamic Analysis on of Skid-Mounted Coal-bed Methane Liquefaction Device using Cryogenic Turbo-Expander

    Science.gov (United States)

    Chen, Shuangtao; Niu, Lu; Zeng, Qiang; Li, Xiaojiang; Lou, Fang; Chen, Liang; Hou, Yu

    2017-12-01

    Coal-bed methane (CBM) reserves are rich in Sinkiang of China, and liquefaction is a critical step for the CBM exploration and utilization. Different from other CBM gas fields in China, CBM distribution in Sinkiang is widespread but scattered, and the pressure, flow-rate and nitrogen content of CBM feed vary significantly. The skid-mounted liquefaction device is suggested as an efficient and economical way to recover methane. Turbo-expander is one of the most important parts which generates the cooling capacity for the cryogenic liquefaction system. Using turbo-expander, more cooling capacity and higher liquefied fraction can be achieved. In this study, skid-mounted CBM liquefaction processes based on Claude cycle are established. Cryogenic turbo-expander with high expansion ratio is employed to improve the efficiency of CBM liquefaction process. The unit power consumption per liquefaction mole flow-rate for CBM feed gas is used as the object function for process optimization, compressor discharge pressure, flow ratio of feed gas to turbo-expander and nitrogen friction are analyzed, and optimum operation range of the liquefaction processes are obtained.

  19. FY 1991 report on the bituminous coal liquefaction section; 1991 nendo rekiseitan ekikabukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-03-01

    The paper reported activities of the bituminous coal liquefaction section in FY 1991. In the 1st bituminous coal liquefaction section meeting, report/discussion were made on the outline of the plan on the FY 1991 research using pilot plant and the support study of pilot plant. In the 2nd section meeting, report was made on 'How the development of coal liquefaction technology should be in the 21st century,' a report made by the joint section of bituminous coal/brown coal liquefaction. In the 3rd section meeting, report/discussion were made on the state of progress of the FY 1991 R and D and results. In the study using the bituminous coal liquefaction pilot plant, report was made on the outline of construction of a 150t/d pilot plant, study on the acquisition of material balance, analytical study of the data on liquefaction tower, testing survey on properties of coal slurry, and testing survey on slurry preheating furnace. In the support study of pilot plant, report was made on the study using 1t/d PUS, study on the development of the optimum coal refining technology and improvement in the distillate distribution, study of conditions for coal liquefaction and study of solvent hydrogenation catalyst. (NEDO)

  20. Comparison of FeS, FeS + S and solid superacid catalytic properties for coal hydro-liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Zhicai Wang; Hengfu Shui; Dexiang Zhang; Jinsheng Gao [East China University of Science and Technology, Shanghai (China). College of Resource and Environment Engineering

    2007-03-15

    Catalyst plays an important role in direct coal liquefaction. This paper focuses on the catalytic behavior of a novel SO{sub 4}{sup 2-}/ZrO{sub 2} superacid catalyst in coal hydro-liquefaction. A series of hydro-liquefaction experiments were conducted under mild conditions - 400{sup o}C, 30 min and H{sub 2} initial pressure 4 MPa in a batch autoclave with a volume of 100 ml. The catalytic property of SO{sub 4}{sup 2-}/ZrO{sub 2} was compared with FeS and FeS + S by Shenhua coal. The liquefaction products catalyzed by different catalysts were analyzed by FTIR spectrum, {sup 1}H NMR spectrum and element analysis. In addition, the SO{sub 4}{sup 2-}/ZrO{sub 2} solid superacid was characterized. The results indicated that the SO{sub 4}{sup 2-}/ZrO{sub 2} solid superacid shows outstanding catalytic property for direct liquefaction of coal and gives the highest coal conversion and gas + oil yield compared to other two catalysts. The THF conversion and the extraction yield of CS{sub 2}/NMP mixed solvent of liquefied coal catalyzed with SO{sub 4}{sup 2-}/ZrO{sub 2} are 76.3%, daf and 81.2%, daf respectively, and the yield of gas + oil is 62.5%, daf under the condition used in this study. The pyrolysis of coal macromolecular clusters can be promoted by catalysts such as FeS, FeS + S and SO{sub 4}{sup 2-}/ZrO{sub 2}. There may be only the pyrolysis of volatile matter and the relaxation of the structure of coal macromolecular clusters in non-catalytic liquefaction at 400{sup o}C. Added sulfur in FeS can improve the catalytic activity of hydrogenation. SO{sub 4}{sup 2-}/ZrO{sub 2} is a notable catalyst in the study of coal direct liquefaction because it shows excellent catalytic activities for the pyrolysis and the hydrogenation. In addition, it has been found that the C-O bond is the most stable group in coal liquefaction reaction except for the covalent bond between carbon and carbon. 34 refs., 6 figs., 6 tabs.

  1. A case study of liquefaction risk analysis based on the thickness and depth of the liquefaction layer using CPT and electric resistivity data in the Hinode area, Itako City, Ibaraki Prefecture, Japan

    Science.gov (United States)

    Jinguuji, Motoharu; Toprak, Selcuk

    2017-12-01

    The Hinode area of Itako City in Ibaraki Prefecture, Japan, suffered some of the most severe liquefaction damage of any areas in the Great Eastern Japan Earthquake in 2011. This liquefaction damage has been investigated by Itako City, as well as by universities and research institutes in Japan. The National Institute of Advanced Industrial Science and Technology (AIST) has carried out numerous investigations along the Tone River, and in particular, intensive surveys were done in the Hinode area. We have conducted a risk analysis based on the thickness and depth of the liquefaction layer measured using cone penetration testing (CPT) data and electric resistivity data obtained in the Hinode area. The distribution of the risk estimated from CPT at 143 points, and that obtained from analysis of the resistivity survey data, agreed with the distribution of actual damage. We also carried out conventional risk analyses method using the liquefaction resistance factor (FL) and liquefaction potential index (PL) methods with CPT data. The results show high PL values over the entire area, but their distribution did not agree well with actual damage in some parts of the study area. Because the analysis of the thickness and depth of the liquefaction layer, using geophysical prospecting methods, can cover a widespread area, this method will be very useful in investigating liquefaction risk, especially for gas and water pipelines.

  2. Report on the FY 1998 results of the New Sunshine Project (B version). Development of coal liquefaction technology (Development of base technology of liquefaction (Project on internationalization of coal liquefaction technology)); 1998 nendo sekitan ekika gijutsu kaihatsu seika hokokusho (B ban). Ekika kiban gijutsu no kaihatsu (sekitan ekika gijutsu no kokusaika jigyo)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    In 1994, a memorandum on the research cooperation was agreed between NEDO and BPPT (The Agency for the Assessment and Application Technology) in Indonesia, based on the request for the coal liquefaction technology cooperation from BPPT. It includes the following items: conference for professionals to be held, invitation and training of Indonesian engineers, activity for joint field survey and potential survey of location of coal liquefaction commercial plant. Further in 1997, the secondary memorandum was concluded for the potential survey for securing the hydrogen required for coal liquefaction by coal gasification. The survey was summarized as the potential survey for location of coal liquefaction. In the testing study for improving economical efficiency of liquefaction process, it was made clear that the higher the Fe content of Banko coal is, the higher the reaction of liquefaction is, and that Fe compounds in coal show catalysis. In the Soroako area in Sulawesi island, there are the nickel mine run by PT. Inco. Soroako limonite is promising as catalyst material for commercial-scale coal liquefaction. In the gasification method, the plant construction cost increases, but the production amount of coal-derived liquid can be increased. That is more profitable than the production of hydrogen from natural gas. (NEDO)

  3. Thermodynamic Evaluation of Floating Production Storage and Offloading Facilities with Liquefaction Processes

    DEFF Research Database (Denmark)

    Nguyen, Tuong-Van; Sánchez, Yamid Alberto Carranza; Junior, Silvio de Oliveira

    2016-01-01

    Floating, production, storage and offloading (FPSO) plants are facilities used in upstream petroleum processing.They have gained interest because they are more flexible than conventional plants and can be used for producingoil and gas in deep-water fields. In general, gas export is challenging...... because of the lack of infrastructure in remotelocations. The present work investigates the possibility of integrating liquefaction processes on such facilities, consideringfour possible petroleum compositions, which differ in their contents of carbon dioxide, light and heavy hydrocarbons.The performance...

  4. A spotlight on liquefaction: evidence from clinical settings and experimental models in tuberculosis.

    Science.gov (United States)

    Cardona, Pere-Joan

    2011-01-01

    Liquefaction is one of the most intriguing aspects of human tuberculosis. It is a major cause of the transition from the infection to active disease (tuberculosis, TB) as well as the transmission of M. tuberculosis to other persons. This paper reviews the natural history of liquefaction in humans from a pathological and radiological point of view and discusses how the experimental models available can be used to address the topic of liquefaction and cavity formation. Different concepts that have been related to liquefaction, from the influence of immune response to mechanical factors, are reviewed. Synchronic necrosis or apoptosis of infected macrophages in a close area, together with an ineffective fibrosis, appears to be clue in this process, in which macrophages, the immune response, and bacillary load interact usually in a particular scenario: the upper lobes of the lung. The summary would be that even if being a stochastic effect, liquefaction would result if the organization of the intragranulomatous necrosis (by means of fibrosis) would be disturbed.

  5. Sunshine Program for fiscal 1981. Research on direct coal-liquefaction reactor; 1981 nendo sekitan chokusetsu ekika hannoki no kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-04-17

    The research aims to develop a new-type high-efficiency reactor for direct coal-liquefaction from a reaction engineering viewpoint and, at the same time, to settle problems expected to occur in industrializing this technique. The research items are Item 1 on the analysis of characteristics of a tubular continuous reactor and Item 2 on high-activity catalysts. Under Item 1, on the assumption that liquefaction reaction is dominantly a reaction in a continuous phase, a reactor is selected in consideration of homogeneous-phase reaction, and operating conditions are set according to the selected reactor and to the liquefaction reaction characteristics. A somewhat large Re number is assigned to the paste. Since the hydrogen partial pressure lowers with the progress of reaction, hydrogen is resupplied at the middle of the reaction tube. The volume of gas increases toward the final stage of reaction, decreasing the continuous phase holdup. Since it is undesirable to let the decrease stand, a vapor-liquid separator is provided for the control of the gas volume. In this fiscal year, investigation is conducted into details so as to determine if the reactor is equipped with intended characteristics. Under Item 2, the iron ore is deemed to be the most promising as disposal catalysts for liquefaction. In this fiscal year, studies are conducted to disclose the activity etc. of catalysts of this type. (NEDO)

  6. Hydrothermal liquefaction of microalgae's for bio oil production

    DEFF Research Database (Denmark)

    Toor, Saqib; Reddy, Harvind; Deng, Shuguang

    process water for algae cultivation. GC-MS, elemental analyzer, calorimeter and nutrient analysis were used to analyze bio-crude, lipid-extracted algae and water samples produced in the hydrothermal liquefaction process. The highest bio-oil yield of 46% was obtained on Nannochloropsis salina at 310 °C...... and 107 bar. For Spirulina platensis algae sample, the highest bio-oil yield is 38% at 350 °C and 195 bar. Preliminary data also indicate that a lipid-extracted algae solid residue sample obtained in the hydrothermal liquefaction process contains a high level of proteins...

  7. Effect of pre-swelling of coal on its solvent extraction and liquefaction properties

    Energy Technology Data Exchange (ETDEWEB)

    Hengfu Shui; Zhicai Wang; Meixia Cao [Anhui University of Technology, Ma' anshan (China). School of Chemistry and Chemical Engineering

    2008-10-15

    Effects of pre-swelling of coal on solvent extraction and liquefaction properties were studied with Shenhua coal. It was found that pre-swelling treatments of the coal in three solvents, i.e., toluene (TOL), N-methyl-2-pyrrolidinone (NMP) and tetralin (THN) increased its extraction yield and liquefaction conversion, and differed the liquefied product distributions. The pre-swollen coals after removing the swelling solvents showed increased conversion in liquefaction compared with that of the swollen coals in the presence of swelling solvents. It was also found that the yields of (oil + gas) in liquefaction of the pre-swollen coals with NMP and TOL dramatically decreased in the presence of swelling solvent. TG and FTIR analyses of the raw coal, the swollen coals and the liquefied products were carried out in order to investigate the mechanism governing the effects of pre-swelling treatment on coal extraction and liquefaction. The results showed that the swelling pre-treatment could disrupt some non-covalent interactions of the coal molecules, relax its network structure and loosened the coal structure. It would thus benefit diffusion of a hydrogen donor solvent into the coal structure during liquefaction, and also enhance the hydrogen donating ability of the hydrogen-rich species derived from the coal. 21 refs., 4 figs., 3 tabs.

  8. Decision Support For Digester Algae Integration For Improved Environmental And Economic Sustainability

    Energy Technology Data Exchange (ETDEWEB)

    2017-06-28

    The Idaho National Laboratory (INL) has teamed with University of Idaho and Boise State University to make the use of ADs more attractive by implementing a two-stage AD and coupling additional processes to the system. The addition of a polyhydroxyalkanoate (PHA) reactor, algae cultivation system, and a biomass treatment system such as fast-pyrolysis or hydrothermal liquefaction (HTL) would further sequester carbon and nutrients, as well as add valuable products that can be sold or used on-site to mitigate costs. The Decision-support for Digester-Algae IntegRation for Improved Environmental and Economic Sustainability (DAIRIEES) technoeconomic model will play a key role in evaluating the effectiveness and viability of this system to achieve economic and environmental sustainability by the dairy industry.

  9. Liquefaction of Lignocellulose in Fractionated Light Bio-Oil: Proof of Concept and Techno-Economic Assessment

    NARCIS (Netherlands)

    Kumar, S.; Lange, Jean Paul; van Rossum, G.; Kersten, Sascha R.A.

    2015-01-01

    The direct thermal liquefaction of lignocellulose can provide a biocrude that could be used as a precursor for biofuels. However, earlier attempts to use the whole reactor effluent as a liquefaction medium, by recycling it to the liquefaction reactor, were hampered by the buildup of heavy products.

  10. Fiscal 1989 report. Coal liquefaction committee; 1989 nendo sekitan ekika iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-03-01

    The committee in this fiscal year had its 1st meeting in June 1989 and 2nd meeting in March 1990, when fiscal 1989 research and development programs and fiscal 1989 research and development results, etc., were reported and discussed. The operating status of the 1 ton/day PSU (process supporting unit) for bituminous coal liquefaction was reported and discussed. The report included its 1st operation for the demonstration of a long-term stable run under standard conditions that continued for trouble-free 50 days, the 2nd operation for the investigation of the effect of liquefaction reaction temperature in which the liquefaction yield recorded the maximum at 450 degrees C with the collection of coal oils of 55 wt.% on the average, and the 3rd operation for the investigation of the effects of liquefaction reaction pressure and catalyst injection size whose details were being analyzed. Reported in relation with the brown coal liquefaction pilot plant was a comprehensive operation of a series of 1st hydrogenation, solvent deashing, and 2nd hydrogenation processes completed after a continuous operation of 460 hours establishing a total operating time of 1050 hours. (NEDO)

  11. Coal liquefaction: A research and development needs assessment: Final report, Volume II

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, H.D.; Burke, F.P.; Chao, K.C.; Davis, B.H.; Gorbaty, M.L.; Klier, K.; Kruse, C.W.; Larsen, J.W.; Lumpkin, R.E.; McIlwain, M.E.; Wender, I.; Stewart, N.

    1989-03-01

    Volume II of this report on an assessment of research needs for coal liquefaction contains reviews of the five liquefaction technologies---direct, indirect, pyrolysis, coprocessing, and bioconversion. These reviews are not meant to be encyclopedic; several outstanding reviews of liquefaction have appeared in recent years and the reader is referred to these whenever applicable. Instead, these chapters contain reviews of selected topics that serve to support the panel's recommendations or to illustrate recent accomplishments, work in progress, or areas of major research interest. At the beginning of each of these chapters is a brief introduction and a summary of the most important research recommendations brought out during the panel discussions and supported by the material presented in the review. A review of liquefaction developments outside the US is included. 594 refs., 100 figs., 60 tabs.

  12. Experimental validation of a mathematical model for seabed liquefaction in waves

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Kirca, Özgür; Fredsøe, Jørgen

    2011-01-01

    This paper summarizes the results of an experimental study directed towards the validation of a mathematical model for the buildup of pore water pressure and resulting liquefaction of marine soils under progressive waves. Experiments were conducted under controlled conditions with silt ( d50 = 0.......070 mm) in a wave flume with a soil pit. Waves with wave heights in the range 7.7-18 cm with the water depth 55 cm and the wave period 1.6 s enabled us to study both the liquefaction and no-liquefaction regime pore water pressure buildup. The experimental data was used to validate the model. A numerical...

  13. Optics of two-stage photovoltaic concentrators with dielectric second stages

    Science.gov (United States)

    Ning, Xiaohui; O'Gallagher, Joseph; Winston, Roland

    1987-04-01

    Two-stage photovoltaic concentrators with Fresnel lenses as primaries and dielectric totally internally reflecting nonimaging concentrators as secondaries are discussed. The general design principles of such two-stage systems are given. Their optical properties are studied and analyzed in detail using computer ray trace procedures. It is found that the two-stage concentrator offers not only a higher concentration or increased acceptance angle, but also a more uniform flux distribution on the photovoltaic cell than the point focusing Fresnel lens alone. Experimental measurements with a two-stage prototype module are presented and compared to the analytical predictions.

  14. Optics of two-stage photovoltaic concentrators with dielectric second stages.

    Science.gov (United States)

    Ning, X; O'Gallagher, J; Winston, R

    1987-04-01

    Two-stage photovoltaic concentrators with Fresnel lenses as primaries and dielectric totally internally reflecting nonimaging concentrators as secondaries are discussed. The general design principles of such two-stage systems are given. Their optical properties are studied and analyzed in detail using computer ray trace procedures. It is found that the two-stage concentrator offers not only a higher concentration or increased acceptance angle, but also a more uniform flux distribution on the photovoltaic cell than the point focusing Fresnel lens alone. Experimental measurements with a two-stage prototype module are presented and compared to the analytical predictions.

  15. Assessment of Soil Liquefaction Potential in Defence Housing Authority, Karachi, Pakistan

    Directory of Open Access Journals (Sweden)

    Sumaira Asif Khan

    2017-04-01

    Full Text Available The occurrence of liquefaction phenomenon may be induced in the event of a large magnitude earthquake but sometimes loose, saturated and poorly graded sand may be subjected to liquefaction due to the vibration produced by other sources. Liquefaction could cause damage to building and infrastructure due to sudden increase of pore pressure in the loose layers of saturated sand causing the loss of bearing capacity and shear strength. Defence Housing Authority (DHA is the well planned residential scheme established by Pakistan Army along the coastal belt of Karachi. The soil occurring in DHA is fine grained, poorly graded and mainly comprises of sandy silt and silty sand of Recent age, where water table is encountered at very shallow depth. Hence, it is important to assess the geotechnical behavior of the soil in DHA area, where most of the high rise buildings and mega civil structures are being constructed. In present study, seismic soil liquefaction was evaluated at 15 sites (30 bore holes in DHA by using simplified empirical method in terms of Factor of Safety (FS. The Relative Density (RD was determined with the help of Standard Penetration Test (SPT data. Grain size analysis was also carried out on each borehole samples. The results revealed that the DHA area is vulnerable to liquefaction during severe seismic event of magnitude between 6.5 and 7.5 in Karachi.

  16. Liquefaction-induced lateral spreading in Oceano, California, during the 2003 San Simeon Earthquake

    Science.gov (United States)

    Holzer, Thomas L.; Noce, Thomas E.; Bennett, Michael J.; Di Alessandro, Carola; Boatwright, John; Tinsley, John C.; Sell, Russell W.; Rosenberg, Lewis I.

    2004-01-01

    The December 22, 2003, San Simeon, California, (M6.5) earthquake caused damage to houses, road surfaces, and underground utilities in Oceano, California. The community of Oceano is approximately 50 miles (80 km) from the earthquake epicenter. Damage at this distance from a M6.5 earthquake is unusual. To understand the causes of this damage, the U.S. Geological Survey conducted extensive subsurface exploration and monitoring of aftershocks in the months after the earthquake. The investigation included 37 seismic cone penetration tests, 5 soil borings, and aftershock monitoring from January 28 to March 7, 2004. The USGS investigation identified two earthquake hazards in Oceano that explain the San Simeon earthquake damage?site amplification and liquefaction. Site amplification is a phenomenon observed in many earthquakes where the strength of the shaking increases abnormally in areas where the seismic-wave velocity of shallow geologic layers is low. As a result, earthquake shaking is felt more strongly than in surrounding areas without similar geologic conditions. Site amplification in Oceano is indicated by the physical properties of the geologic layers beneath Oceano and was confirmed by monitoring aftershocks. Liquefaction, which is also commonly observed during earthquakes, is a phenomenon where saturated sands lose their strength during an earthquake and become fluid-like and mobile. As a result, the ground may undergo large permanent displacements that can damage underground utilities and well-built surface structures. The type of displacement of major concern associated with liquefaction is lateral spreading because it involves displacement of large blocks of ground down gentle slopes or towards stream channels. The USGS investigation indicates that the shallow geologic units beneath Oceano are very susceptible to liquefaction. They include young sand dunes and clean sandy artificial fill that was used to bury and convert marshes into developable lots. Most of

  17. Single-stage-to-orbit versus two-stage-two-orbit: A cost perspective

    Science.gov (United States)

    Hamaker, Joseph W.

    1996-03-01

    This paper considers the possible life-cycle costs of single-stage-to-orbit (SSTO) and two-stage-to-orbit (TSTO) reusable launch vehicles (RLV's). The analysis parametrically addresses the issue such that the preferred economic choice comes down to the relative complexity of the TSTO compared to the SSTO. The analysis defines the boundary complexity conditions at which the two configurations have equal life-cycle costs, and finally, makes a case for the economic preference of SSTO over TSTO.

  18. Japan`s New Sunshine Project. 20. 1995 annual summary of coal liquefaction and gasification

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The paper described a summary of the 1995 study on coal liquefaction and gasification under the New Sunshine Project. As for coal liquefaction, a study was made of liquefaction characteristics and catalysts of various coals. Also studied were liquefaction conditions for quality improvement of liquefaction products, an evaluation method of quality of coal liquid, and a utilization method of coal liquid. In order to prevent carbonization and realize effective liquefaction, a study was conducted for elucidation of the reaction mechanism of high pressure hydrogenation. In a 150t/d pilot plant using hydrogen transfer hydrogenation solvents, the NEDOL method was studied using various catalysts and kinds of coals. This is a step prior to data acquisition for engineering, actual construction of equipment and operation. A 1t/d process supporting unit is a unit to support it. The unit conducts studies on slurry letdown valves and synthetic iron sulfide catalysts, screening of Chinese coals, etc. As to coal gasification, the paper added to the basic research the combined cycle power generation using entrained flow coal gasification for improvement of thermal efficiency and environmental acceptability and the HYCOL method for hydrogen production. 68 refs., 40 figs.

  19. Application of Algae as Cosubstrate To Enhance the Processability of Willow Wood for Continuous Hydrothermal Liquefaction

    DEFF Research Database (Denmark)

    Sintamarean, Iulia-Maria; Pedersen, Thomas Helmer; Zhao, Xueli

    2017-01-01

    This work proposes a novel strategy to improve the continuous processing of wood slurries in hydrothermal liquefaction systems by coprocessing with algae. Of all algae tested, brown seaweeds and microalgae perform best in preventing slurries dewatering, the main reason for pumpability issues...... with wood slurries. Rheological tests (viscosity–shear rate profile) indicate that the addition of these two algae to the wood slurry causes the highest increase in viscosity, which coincides with improved wood slurries stability and pumpability. Hydrothermal liquefaction of wood-algae slurries at 400 °C...

  20. A Spotlight on Liquefaction: Evidence from Clinical Settings and Experimental Models in Tuberculosis

    Directory of Open Access Journals (Sweden)

    Pere-Joan Cardona

    2011-01-01

    Full Text Available Liquefaction is one of the most intriguing aspects of human tuberculosis. It is a major cause of the transition from the infection to active disease (tuberculosis, TB as well as the transmission of M. tuberculosis to other persons. This paper reviews the natural history of liquefaction in humans from a pathological and radiological point of view and discusses how the experimental models available can be used to address the topic of liquefaction and cavity formation. Different concepts that have been related to liquefaction, from the influence of immune response to mechanical factors, are reviewed. Synchronic necrosis or apoptosis of infected macrophages in a close area, together with an ineffective fibrosis, appears to be clue in this process, in which macrophages, the immune response, and bacillary load interact usually in a particular scenario: the upper lobes of the lung. The summary would be that even if being a stochastic effect, liquefaction would result if the organization of the intragranulomatous necrosis (by means of fibrosis would be disturbed.

  1. Predicted Liquefaction in the Greater Oakland and Northern Santa Clara Valley Areas for a Repeat of the 1868 Hayward Earthquake

    Science.gov (United States)

    Holzer, T. L.; Noce, T. E.; Bennett, M. J.

    2008-12-01

    Probabilities of surface manifestations of liquefaction due to a repeat of the 1868 (M6.7-7.0) earthquake on the southern segment of the Hayward Fault were calculated for two areas along the margin of San Francisco Bay, California: greater Oakland and the northern Santa Clara Valley. Liquefaction is predicted to be more common in the greater Oakland area than in the northern Santa Clara Valley owing to the presence of 57 km2 of susceptible sandy artificial fill. Most of the fills were placed into San Francisco Bay during the first half of the 20th century to build military bases, port facilities, and shoreline communities like Alameda and Bay Farm Island. Probabilities of liquefaction in the area underlain by this sandy artificial fill range from 0.2 to ~0.5 for a M7.0 earthquake, and decrease to 0.1 to ~0.4 for a M6.7 earthquake. In the greater Oakland area, liquefaction probabilities generally are less than 0.05 for Holocene alluvial fan deposits, which underlie most of the remaining flat-lying urban area. In the northern Santa Clara Valley for a M7.0 earthquake on the Hayward Fault and an assumed water-table depth of 1.5 m (the historically shallowest water level), liquefaction probabilities range from 0.1 to 0.2 along Coyote and Guadalupe Creeks, but are less than 0.05 elsewhere. For a M6.7 earthquake, probabilities are greater than 0.1 along Coyote Creek but decrease along Guadalupe Creek to less than 0.1. Areas with high probabilities in the Santa Clara Valley are underlain by latest Holocene alluvial fan levee deposits where liquefaction and lateral spreading occurred during large earthquakes in 1868 and 1906. The liquefaction scenario maps were created with ArcGIS ModelBuilder. Peak ground accelerations first were computed with the new Boore and Atkinson NGA attenuation relation (2008, Earthquake Spectra, 24:1, p. 99-138), using VS30 to account for local site response. Spatial liquefaction probabilities were then estimated using the predicted ground motions

  2. Whole Algae Hydrothermal Liquefaction Technology Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Biddy, Mary J.; Davis, Ryan; Jones, Susanne B.; Zhu, Yunhua

    2013-03-31

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This pathway case investigates the feasibility of using whole wet microalgae as a feedstock for conversion via hydrothermal liquefaction. Technical barriers and key research needs have been assessed in order for the hydrothermal liquefaction of microalgae to be competitive with petroleum-derived gasoline, diesel and jet range blendstocks.

  3. Development of an extruder-feeder biomass direct liquefaction process. Volume 2, Parts 4--8: Final report

    Energy Technology Data Exchange (ETDEWEB)

    White, D.H.; Wolf, D. [Arizona Univ., Tucson, AZ (United States). Dept. of Chemical Engineering

    1991-10-01

    As an abundant, renewable, domestic energy resource, biomass could help the United States reduce its dependence on imported oil. Biomass is the only renewable energy technology capable of addressing the national need for liquid transportation fuels. Thus, there is an incentive to develop economic conversion processes for converting biomass, including wood, into liquid fuels. Through research sponsored by the US DOE`s Biomass Thermochemical Conversion Program, the University of Arizona has developed a unique biomass direct liquefaction system. The system features a modified single-screw extruder capable of pumping solid slurries containing as high as 60 wt% wood flour in wood oil derived vacuum bottoms at pressures up to 3000 psi. The extruder-feeder has been integrated with a unique reactor by the University to form a system which offers potential for improving high pressure biomass direct liquefaction technology. The extruder-feeder acts simultaneously as both a feed preheater and a pumping device for injecting wood slurries into a high pressure reactor in the biomass liquefaction process. An experimental facility was constructed and following shakedown operations, wood crude oil was produced by mid-1985. By July 1988, a total of 57 experimental continuous biomass liquefaction runs were made using White Birch wood feedstock. Good operability was achieved at slurry feed rates up to 30 lb/hr, reactor pressures from 800 to 3000 psi and temperatures from 350{degree}C to 430{degree}C under conditions covering a range of carbon monoxide feed rates and sodium carbonate catalyst addition. Crude wood oils containing as little as 6--10 wt% residual oxygen were produced. 38 refs., 82 figs., 26 tabs.

  4. Techno-economic Analysis of Acid Gas Removal and Liquefaction for Pressurized LNG

    Science.gov (United States)

    Lee, S. H.; Seo, Y. K.; Chang, D. J.

    2018-05-01

    This study estimated the life cycle cost (LCC) of an acid gas removal and a liquefaction processes for Pressurized LNG (PLNG) production and compared the results with the cost of normal LNG production. PLNG is pressurized LNG that is liquefied at a higher pressure and temperature than normal LNG. Due to the high temperature, the energy for liquefaction is reduced. The allowable CO2 concentration in PLNG is increased up to 3 mol% when the product pressure 25 bar. An amine process with 35 wt% of diethanolamine (DEA) aqueous solution and a nitrogen expansion cycle were selected for the acid gas removal and the liquefaction processes, respectively. Two types of CO2 concentration in the feed gas were investigated to analyze their impacts on the acid gas removal unit. When the CO2 concentration was 5 mol%, the acid gas removal unit was required for both LNG and PLNG production. However, the acid gas removal unit was not necessary in PLNG when the concentration was 0.5 mol% and the pressure was higher than 15 bar. The results showed that the LCC of PLNG was reduced by almost 35% relative to that of LNG when the PLNG pressure was higher than 15 bar.

  5. Assessment and mitigation of liquefaction

    International Nuclear Information System (INIS)

    Czelada, J. A.; Melentijevic, S.

    2014-01-01

    The simplified empirical procedure in its original form presented in Youd et al (2001) and some further developments given in Idriss and Boulanger (2006) for evaluating liquefaction resistance of soils is presented in this paper only for the criteria based on standard penetration test (SPT). Methods for estimating the ground improvement techniques by stone columns and dynamics compaction are presented. For stone columns Priebe method (1995) and homogenized method (equivalent parameters) are present. for dynamic compaction methods proposed by Recomendacion Geotecnica para las Obras Maritimas y/o Porturaria - ROM 0.5-05 (2005) and Nashed et al. (2009) are described. These analysis methods for each ground improvement technique are compared in two different case histories showing similar results in each one. (Author)

  6. Enhancement of energy performance in a boil-off gas re-liquefaction system of LNG carriers using ejectors

    International Nuclear Information System (INIS)

    Tan, Hongbo; Zhao, Qingxuan; Sun, Nannan; Li, Yanzhong

    2016-01-01

    Highlights: • An ejector-enhanced LNG boil-off gas (BOG) re-liquefaction system is proposed. • The new system has an improvement of 28% in COP over the existing system. • The specific energy consumption of the new system is reduced to 0.59 kW h/kg(BOG). • The power consumption of 754.1 kW is saved in the case study. - Abstract: An ejector-enhanced Liquefied Natural Gas (LNG) boil-off gas (BOG) re-liquefaction system is proposed to improve the energy efficiency of the existing system. In the new system, two ejectors are respectively used to reduce the energy loss in the expansion of the pressurized BOG and inject a part of fuel BOG into the compression system, and a recuperator is employed to recover the cold energy of the BOG exited from LNG tank. The performance improvement of the proposed system is analysed on the basis of the simulation in Aspen HYSYS. In the case of the re-liquefaction capacity of 4557.6 kg/h, the coefficient of performance (COP) and exergy efficiency can be increased by 28%, and the specific energy consumption (SEC) reduced from 0.756 to 0.59 kW h/kg(BOG) compared to the conventional BOG re-liquefaction system. Correspondingly, the power consumption of 754.1 kW is saved. This means that applying ejectors can effectively improve the energy efficiency of the existing BOG re-liquefaction system for LNG carriers.

  7. An Integrated Simulation, Inference and Optimization Approach for Groundwater Remediation with Two-stage Health-Risk Assessment

    Directory of Open Access Journals (Sweden)

    Aili Yang

    2018-05-01

    Full Text Available In this study, an integrated simulation, inference and optimization approach with two-stage health risk assessment (i.e., ISIO-THRA is developed for supporting groundwater remediation for a petroleum-contaminated site in western Canada. Both environmental standards and health risk are considered as the constraints in the ISIO-THRA model. The health risk includes two parts: (1 the health risk during the remediation process and (2 the health risk in the natural attenuation period after remediation. In the ISIO-THRA framework, the relationship between contaminant concentrations and time is expressed through first-order decay models. The results demonstrate that: (1 stricter environmental standards and health risk would require larger pumping rates for the same remediation duration; (2 higher health risk may happen in the period of the remediation process; (3 for the same environmental standard and acceptable health-risk level, the remediation techniques that take the shortest time would be chosen. ISIO-THRA can help to systematically analyze interaction among contaminant transport, remediation duration, and environmental and health concerns, and further provide useful supportive information for decision makers.

  8. Direct hydrothermal liquefaction of undried macroalgae Enteromorpha prolifera using acid catalysts

    International Nuclear Information System (INIS)

    Yang, Wenchao; Li, Xianguo; Liu, Shishi; Feng, Lijuan

    2014-01-01

    Highlights: • Bio-oil from liquefaction of wet E. prolifera was as feasible as dry powder. • Adding acid catalysts could improve the flow property of bio-oil. • Alkenes in the bio-oil converted to ketones in the presence of acid catalysts. • Content of 5-methyl furfural increased in the bio-oil obtained with acid catalysts. • Esters were formed in the bio-oil when adding sulfuric acid as a catalyst. - Abstract: Direct liquefaction of macroalgae Enteromorpha prolifera without predrying treatment was performed in a batch reactor. Effects of temperature, reaction time, biomass-to-water ratio and acid catalysts (sulfuric acid and acetic acid) on liquefaction products were investigated. Raw material and liquefaction products were analyzed by elemental analysis, Fourier transform infrared (FT-IR) and gas chromatography–mass spectrometry (GC–MS). Results showed that liquefaction at 290 °C for 20 min with 1:3 biomass-to-water ratio produced the highest bio-oil yield of 28.4 wt%, and high heating value (HHV) was 29.5 MJ/kg. Main components of bio-oil were fatty acids, ketones, alkenes and 5-methyl furfural, and main components of water soluble organics (WSOs) were pyridines, carboxylic acids and glycerol. In the bio-oil obtained with acid catalysts, content of ketones significantly increased while alkenes disappeared. Content of 5-methyl furfural also increased. Flow property of bio-oils was improved in the presence of acid catalysts. Moreover, esters were formed when adding sulfuric acid

  9. Study on sand particles creep model and open pit mine landslide mechanism caused by sand fatigue liquefaction

    Science.gov (United States)

    Du, Dong-Ning; Wang, Lai-Gui; Zhang, Xiang-Dong; Zhang, Shu-Kun

    2017-06-01

    The sand particles in the sand - rock composite slope of the open pit mine occurs creep deformation and fatigue liquefaction under the action of vehicle load vibration and hydraulic gradient, which causes landslide geological disasters and it destroys the surface environment. To reveal the mechanism, a mechanics model based on the model considering the soil structural change with a new “plastic hinge” element is developed, to improve its constitutive and creep curve equations. Data from sand creep experiments are used to identify the parameters in the model and to validate the model. The results show that the mechanical model can describe the rotation progress between the sand particles, disclose the negative acceleration creep deformation stage during the third phase, and require fewer parameters while maintaining accuracy. It provides a new creep model considering rotation to analyze sand creep mechanism, which provides a theoretical basis for revealing the open pit mine landslide mechanism induced by creep deformation and fatigue liquefaction of sandy soil.

  10. Thermal properties of biopolyol from oil palm fruit fibre (OPFF) using solvolysis liquefaction technique

    Science.gov (United States)

    Kormin, Shaharuddin; Rus, Anika Zafiah M.; Azahari, M. Shafiq M.

    2017-09-01

    Liquefaction is known to be an effective method for converting biomass into a biopolyol. The biomass liquefaction of oil palm fruit waste (PFW) in the presence of liquefaction solvent/polyhydric alcohol (PA): polyethylene glycol 400 (PEG400) using sulfuric acid as catalyst was studied. For all experiments, the liquefaction was conducted at 150°C and atmospheric pressure. The mass ratio of OPFW to liquefaction solvents used in all the experiments was, 1/3. Thermogravimetric analyses (TGA) were used to analyze their biopolyol and residue behaviors. It was found that thermal stability of oil palm mesocarp fibre (PM), oil palm shell (PS) and oil palm kernel (PK) fibre exhibited the first degradation of hard segment at (232, 104, 230°C) and the second degradation of soft segment at (314, 226, 412°C) as compared to PM, PS and PK residue which (229, 102, 227°C) of hard segment and (310, 219, 299°C) of segment, respectively. This behavior of thermal degradation of the hard segment and soft segment of biopolyol was changes after undergo solvolysis liquefaction process. The result analysis showed that the resulting biopolyol and its residue was suitable monomer for polyurethane (PU) synthesis for the production of PU foams.

  11. Direct liquefaction of plastics and coprocessing of coal with plastics

    Energy Technology Data Exchange (ETDEWEB)

    Huffman, G.P.; Feng, Z.; Mahajan, V. [Univ. of Kentucky, Lexington, KY (United States)

    1995-12-31

    The objectives of this work were to optimize reaction conditions for the direct liquefaction of waste plastics and the coprocessing of coal with waste plastics. In previous work, the direct liquefaction of medium and high density polyethylene (PE), polypropylene (PPE), poly(ethylene terephthalate) (PET), and a mixed plastic waste, and the coliquefaction of these plastics with coals of three different ranks was studied. The results established that a solid acid catalyst (HZSM-5 zeolite) was highly active for the liquefaction of the plastics alone, typically giving oil yields of 80-95% and total conversions of 90-100% at temperatures of 430-450 {degrees}C. In the coliquefaction experiments, 50:50 mixtures of plastic and coal were used with a tetralin solvent (tetralin:solid = 3:2). Using approximately 1% of the HZSM-5 catalyst and a nanoscale iron catalyst, oil yields of 50-70% and total conversion of 80-90% were typical. In the current year, further investigations were conducted of the liquefaction of PE, PPE, and a commingled waste plastic obtained from the American Plastics Council (APC), and the coprocessing of PE, PPE and the APC plastic with Black Thunder subbituminous coal. Several different catalysts were used in these studies.

  12. Use of liquefaction-induced features for paleoseismic analysis - An overview of how seismic liquefaction features can be distinguished from other features and how their regional distribution and properties of source sediment can be used to infer the location and strength of Holocene paleo-earthquakes

    Science.gov (United States)

    Obermeier, S.F.

    1996-01-01

    morphology that is consistent with a very sudden application of a large hydraulic force. This article discusses case studies in widely separated and different geological settings: coastal South Carolina, the New Madrid seismic zone, the Wabash Valley seismic zone, and coastal Washington State. These studies encompass most of the range of settings and the types of liquefaction-induced features likely to be encountered anywhere. The case studies describe the observed features and the logic for assigning a seismic liquefaction origin to them. Also discussed are some types of sediment deformations that can be misinterpreted as having a seismic origin. Two independent methods for estimating prehistoric magnitude are discussed briefly. One method is based on determination of the maximum distance from the epicenter over which liquefaction-induced effects have formed. The other method is based on use of geotechnical engineering techniques at sites of marginal liquefaction, in order to bracket the peak accelerations as a function of epicentral distance; these accelerations can then be compared with predictions from seismological models.

  13. Comparisons of single-stage and two-stage approaches to genomic selection.

    Science.gov (United States)

    Schulz-Streeck, Torben; Ogutu, Joseph O; Piepho, Hans-Peter

    2013-01-01

    Genomic selection (GS) is a method for predicting breeding values of plants or animals using many molecular markers that is commonly implemented in two stages. In plant breeding the first stage usually involves computation of adjusted means for genotypes which are then used to predict genomic breeding values in the second stage. We compared two classical stage-wise approaches, which either ignore or approximate correlations among the means by a diagonal matrix, and a new method, to a single-stage analysis for GS using ridge regression best linear unbiased prediction (RR-BLUP). The new stage-wise method rotates (orthogonalizes) the adjusted means from the first stage before submitting them to the second stage. This makes the errors approximately independently and identically normally distributed, which is a prerequisite for many procedures that are potentially useful for GS such as machine learning methods (e.g. boosting) and regularized regression methods (e.g. lasso). This is illustrated in this paper using componentwise boosting. The componentwise boosting method minimizes squared error loss using least squares and iteratively and automatically selects markers that are most predictive of genomic breeding values. Results are compared with those of RR-BLUP using fivefold cross-validation. The new stage-wise approach with rotated means was slightly more similar to the single-stage analysis than the classical two-stage approaches based on non-rotated means for two unbalanced datasets. This suggests that rotation is a worthwhile pre-processing step in GS for the two-stage approaches for unbalanced datasets. Moreover, the predictive accuracy of stage-wise RR-BLUP was higher (5.0-6.1%) than that of componentwise boosting.

  14. On the prior probabilities for two-stage Bayesian estimates

    International Nuclear Information System (INIS)

    Kohut, P.

    1992-01-01

    The method of Bayesian inference is reexamined for its applicability and for the required underlying assumptions in obtaining and using prior probability estimates. Two different approaches are suggested to determine the first-stage priors in the two-stage Bayesian analysis which avoid certain assumptions required for other techniques. In the first scheme, the prior is obtained through a true frequency based distribution generated at selected intervals utilizing actual sampling of the failure rate distributions. The population variability distribution is generated as the weighed average of the frequency distributions. The second method is based on a non-parametric Bayesian approach using the Maximum Entropy Principle. Specific features such as integral properties or selected parameters of prior distributions may be obtained with minimal assumptions. It is indicated how various quantiles may also be generated with a least square technique

  15. To the vibrational over wetting and liquefaction effects in moistured soils

    International Nuclear Information System (INIS)

    Karimov, F.H.; Oripov, G.O.; Saidov, R.M.; Tojibekov, M.

    2003-01-01

    There is a lot of evidence of the dynamical effects in soils when they become wetted or during or after the earthquakes or explosions. There are some quantitative estimates for the vibrational wetting and liquefaction of soils under consideration. For the models in the present research the moistured sands and weak soils like losses are accepted. The first model is focusing on soil fractures sliding down under the action of vibrations, tightening of a hard phase, squeezing water phase out and thus bringing to soil liquefaction. The second is based on soil fractures plunging at the action of vibrations into the aquatic background. This mechanism seems to be more effective for the high degree moistured soils. The third mechanism is based on capillary phenomena in moistured porous medium. When inertia forces are large enough the resultant force, consisting of sliding down gravity component and inertia forces, overcomes friction and fracture becomes unstable. Both vibrations amplitude and frequency are the stability controlling factors, playing an important role in the vibrational wetting and liquefaction effects through porous water phase squeezing out or capillary lifting phenomena leading to the wetting or liquefaction of the medium. (author)

  16. Comparative effectiveness of one-stage versus two-stage basilic vein transposition arteriovenous fistulas.

    Science.gov (United States)

    Ghaffarian, Amir A; Griffin, Claire L; Kraiss, Larry W; Sarfati, Mark R; Brooke, Benjamin S

    2018-02-01

    Basilic vein transposition (BVT) fistulas may be performed as either a one-stage or two-stage operation, although there is debate as to which technique is superior. This study was designed to evaluate the comparative clinical efficacy and cost-effectiveness of one-stage vs two-stage BVT. We identified all patients at a single large academic hospital who had undergone creation of either a one-stage or two-stage BVT between January 2007 and January 2015. Data evaluated included patient demographics, comorbidities, medication use, reasons for abandonment, and interventions performed to maintain patency. Costs were derived from the literature, and effectiveness was expressed in quality-adjusted life-years (QALYs). We analyzed primary and secondary functional patency outcomes as well as survival during follow-up between one-stage and two-stage BVT procedures using multivariate Cox proportional hazards models and Kaplan-Meier analysis with log-rank tests. The incremental cost-effectiveness ratio was used to determine cost savings. We identified 131 patients in whom 57 (44%) one-stage BVT and 74 (56%) two-stage BVT fistulas were created among 8 different vascular surgeons during the study period that each performed both procedures. There was no significant difference in the mean age, male gender, white race, diabetes, coronary disease, or medication profile among patients undergoing one- vs two-stage BVT. After fistula transposition, the median follow-up time was 8.3 months (interquartile range, 3-21 months). Primary patency rates of one-stage BVT were 56% at 12-month follow-up, whereas primary patency rates of two-stage BVT were 72% at 12-month follow-up. Patients undergoing two-stage BVT also had significantly higher rates of secondary functional patency at 12 months (57% for one-stage BVT vs 80% for two-stage BVT) and 24 months (44% for one-stage BVT vs 73% for two-stage BVT) of follow-up (P < .001 using log-rank test). However, there was no significant difference

  17. Post Hoc Analysis of Passive Cavitation Imaging for Classification of Histotripsy-Induced Liquefaction in Vitro.

    Science.gov (United States)

    Bader, Kenneth B; Haworth, Kevin J; Maxwell, Adam D; Holland, Christy K

    2018-01-01

    Histotripsy utilizes focused ultrasound to generate bubble clouds for transcutaneous tissue liquefaction. Bubble activity maps are under development to provide image guidance and monitor treatment progress. The aim of this paper was to investigate the feasibility of using plane wave B-mode and passive cavitation images to be used as binary classifiers of histotripsy-induced liquefaction. Prostate tissue phantoms were exposed to histotripsy pulses over a range of pulse durations (5- ) and peak negative pressures (12-23 MPa). Acoustic emissions were recorded during the insonation and beamformed to form passive cavitation images. Plane wave B-mode images were acquired following the insonation to detect the hyperechoic bubble cloud. Phantom samples were sectioned and stained to delineate the liquefaction zone. Correlation between passive cavitation and plane wave B-mode images and the liquefaction zone was assessed using receiver operating characteristic (ROC) curve analysis. Liquefaction of the phantom was observed for all the insonation conditions. The area under the ROC (0.94 versus 0.82), accuracy (0.90 versus 0.83), and sensitivity (0.81 versus 0.49) was greater for passive cavitation images relative to B-mode images ( ) along the azimuth of the liquefaction zone. The specificity was greater than 0.9 for both imaging modalities. These results demonstrate a stronger correlation between histotripsy-induced liquefaction and passive cavitation imaging compared with the plane wave B-mode imaging, albeit with limited passive cavitation image range resolution.

  18. Design considerations for single-stage and two-stage pneumatic pellet injectors

    International Nuclear Information System (INIS)

    Gouge, M.J.; Combs, S.K.; Fisher, P.W.; Milora, S.L.

    1988-09-01

    Performance of single-stage pneumatic pellet injectors is compared with several models for one-dimensional, compressible fluid flow. Agreement is quite good for models that reflect actual breech chamber geometry and incorporate nonideal effects such as gas friction. Several methods of improving the performance of single-stage pneumatic pellet injectors in the near term are outlined. The design and performance of two-stage pneumatic pellet injectors are discussed, and initial data from the two-stage pneumatic pellet injector test facility at Oak Ridge National Laboratory are presented. Finally, a concept for a repeating two-stage pneumatic pellet injector is described. 27 refs., 8 figs., 3 tabs

  19. Dual stage active magnetic regenerator and method

    Science.gov (United States)

    Pecharsky, Vitalij K.; Gschneidner, Jr., Karl A.

    1999-03-30

    A dual stage active magnetic regenerator refrigerator as well as method using the Joule-Brayton thermodynamic cycle includes a high temperature stage refrigerant comprising DyAl.sub.2 or (Dy.sub.1-x Er.sub.x)Al.sub.2 where x is selected to be greater than 0 and less than about 0.3 in combination with a low temperature stage comprising (Dy.sub.1-x Er.sub.x)Al.sub.2 where x is selected to be greater than about 0.5 and less than 1 to provide significantly improved refrigeration efficiency in the liquefaction of gaseous hydrogen.

  20. Thermochemical liquefaction characteristics of microalgae in sub- and supercritical ethanol

    Energy Technology Data Exchange (ETDEWEB)

    You, Qiao; Chen, Liang [College of Environmental Science and Engineering, Hunan University, Changsha (China); Key Laboratory of Environment Biology and Pollution Control, Ministry of Education, Changsha (China)

    2011-01-15

    Thermochemical liquefaction characteristics of Spirulina, a kind of high-protein microalgae, were investigated with the sub- and supercritical ethanol as solvent in a 1000 mL autoclave. The influences of various liquefaction parameters on the yields of products (bio-oil and residue) from the liquefaction of Spirulina were studied, such as the reaction temperature (T), the S/L ratio (R{sub 1}, solid: Spirulina, liquid: ethanol), the solvent filling ratio (R{sub 2}) and the type and dosage of catalyst. Without catalyst, the bio-oil yields were in the range of 35.4 wt.% and 45.3 wt.% depending on the changes of T, R{sub 1} and R{sub 2}. And the bio-oil yields increased generally with increasing T and R{sub 2}, while the bio-oil yields reduced with increasing R{sub 1}. The FeS catalyst was certified to be an ideal catalyst for the liquefaction of Spirulina microalgae for its advantages on promoting bio-oil production and suppressing the formation of residue. The optimal dosage of catalyst (FeS) was ranging from 5-7 wt.%. The elemental analyses and FT-IR and GC-MS measurements for the bio-oils revealed that the liquid products have much higher heating values than the crude Spirulina sample and fatty acid ethyl ester compounds were dominant in the bio-oils, irrespective of whether catalyst was used. (author)

  1. Activity and selectivity of three molybdenum catalysts for coal liquefaction reactions

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, C.W.; Pellegrino, J.L.

    The activity and selectivity of three different molybdenum catalysts for reactions occurring in coal liquefaction, specifically for hydrogenation (HYD), hydrodeoxygenation (HDO), hydrodenitrogenation (HDN), hydrodesulfurization (HDS), and hydrocracking (HYC), have been examined. The three molybdenum catalysts used were molybdenum napthenate, molybdenum on ..gamma..-alumina, and a precipitated, disordered MoS/sub 2/. Molybdenum naphthenate was most selective for HYD and HDN. All three catalysts exhibited approximately equal activity for HDS and HDO and little selectivity for HYC of alkyl bridge structures. The activity and selectivity of the three molybdenum catalysts for producing hydrocarbons and removing heteroatoms from coal during liquefaction were determined and compared. Molybdenum naphthenate was the most active catalyst for hydrocarbon production and removal of nitrogen- and oxygen-containing species during coal liquefaction. 31 refs., 4 figs., 7 tabs.

  2. Role of expanders in helium liquefaction cycles: Parametric studies using Collins cycle

    International Nuclear Information System (INIS)

    Thomas, Rijo Jacob; Ghosh, Parthasarathi; Chowdhury, Kanchan

    2011-01-01

    Large scale helium liquefaction/refrigeration plant is a key subsystem of fusion devices. Performance of these plants is dependent on a number of geometric and operating parameters of its constituting components such as compressors, heat exchangers, expanders, valves, etc. Expander has been chosen as the subject matter of analyses in the present study. As the sensible cold of helium vapor is lost in liquefiers, the expanders in liquefaction cycles have to provide more refrigeration than those in refrigeration cycles. The expander parameters such as rate of mass flow, operating pressure, inlet temperature, etc. are inter-dependent, and hence, it is difficult to predict the system behavior with variation of a particular parameter. This necessitates the use of process simulators. Parametric studies have been performed on Collins helium liquefaction cycle using Aspen HYSYS. Collins cycle has all the basic characteristics of a large-scale helium liquefier and the results of this study may be extrapolated to understand the behavior of large scale helium liquefiers. The study shows that the maximum liquid production is obtained when 80% of the compressor flow is diverted through the expanders and it is equally distributed between the two expanders. The relationships between the liquid production and the isentropic efficiency of expanders are almost linear and both the higher and lower temperature expanders exhibit similar trends.

  3. Role of expanders in helium liquefaction cycles: Parametric studies using Collins cycle

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Rijo Jacob, E-mail: rijojthomas@gmail.com [Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur, West Bengal 721302 (India); Ghosh, Parthasarathi; Chowdhury, Kanchan [Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur, West Bengal 721302 (India)

    2011-06-15

    Large scale helium liquefaction/refrigeration plant is a key subsystem of fusion devices. Performance of these plants is dependent on a number of geometric and operating parameters of its constituting components such as compressors, heat exchangers, expanders, valves, etc. Expander has been chosen as the subject matter of analyses in the present study. As the sensible cold of helium vapor is lost in liquefiers, the expanders in liquefaction cycles have to provide more refrigeration than those in refrigeration cycles. The expander parameters such as rate of mass flow, operating pressure, inlet temperature, etc. are inter-dependent, and hence, it is difficult to predict the system behavior with variation of a particular parameter. This necessitates the use of process simulators. Parametric studies have been performed on Collins helium liquefaction cycle using Aspen HYSYS. Collins cycle has all the basic characteristics of a large-scale helium liquefier and the results of this study may be extrapolated to understand the behavior of large scale helium liquefiers. The study shows that the maximum liquid production is obtained when 80% of the compressor flow is diverted through the expanders and it is equally distributed between the two expanders. The relationships between the liquid production and the isentropic efficiency of expanders are almost linear and both the higher and lower temperature expanders exhibit similar trends.

  4. Evaluation of liquefaction potential of soil based on standard penetration test using multi-gene genetic programming model

    Science.gov (United States)

    Muduli, Pradyut; Das, Sarat

    2014-06-01

    This paper discusses the evaluation of liquefaction potential of soil based on standard penetration test (SPT) dataset using evolutionary artificial intelligence technique, multi-gene genetic programming (MGGP). The liquefaction classification accuracy (94.19%) of the developed liquefaction index (LI) model is found to be better than that of available artificial neural network (ANN) model (88.37%) and at par with the available support vector machine (SVM) model (94.19%) on the basis of the testing data. Further, an empirical equation is presented using MGGP to approximate the unknown limit state function representing the cyclic resistance ratio (CRR) of soil based on developed LI model. Using an independent database of 227 cases, the overall rates of successful prediction of occurrence of liquefaction and non-liquefaction are found to be 87, 86, and 84% by the developed MGGP based model, available ANN and the statistical models, respectively, on the basis of calculated factor of safety (F s) against the liquefaction occurrence.

  5. Continuous production of bio-oil by catalytic liquefaction from wet distiller’s grain with solubles (WDGS) from bio-ethanol production

    International Nuclear Information System (INIS)

    Toor, Saqib Sohail; Rosendahl, Lasse; Nielsen, Mads Pagh; Glasius, Marianne; Rudolf, Andreas; Iversen, Steen Brummerstedt

    2012-01-01

    Bio-refinery concepts are currently receiving much attention due to the drive toward flexible, highly efficient systems for utilization of biomass for food, feed, fuel and bio-chemicals. One way of achieving this is through appropriate process integration, in this particular case combining enzymatic bio-ethanol production with catalytic liquefaction of the wet distillers grains with soluble, a byproduct from the bio-ethanol process. The catalytic liquefaction process is carried out at sub-critical conditions (280–370 °C and 25 MPa) in the presence of a homogeneous alkaline and a heterogeneous Zirconia catalyst, a process known as the Catliq ® process. In the current work, catalytic conversion of WDGS was performed in a continuous pilot plant with a maximum capacity of 30 dm 3 h −1 of wet biomass. In the process, WDGS was converted to bio-oil, gases and water-soluble organic compounds. The oil obtained was characterized using several analysis methods, among them elementary analysis and GC–MS. The study shows that WDGS can be converted to bio oil with high yields. The results also indicate that through the combination of bio-ethanol production and catalytic liquefaction, it is possible to significantly increase the liquid product yield and scope, opening up for a wider end use applicability. -- Highlights: ► Hydrothermal liquefaction of wet biomass. ► Product phase analysis: oil, acqeous, gas and mineral phase. ► Energy and mass balance evaluation.

  6. Report for fiscal 1995 by basic liquefaction technology subcommittee; 1995 nendo ekika kiban gijutsu bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Delivered at the 1st meeting are a report on the fiscal 1995 research plan and an interim report, involving the use of coal-derived oils, research on refining technology using a PDU (process developing unit), reforming technology and petroleum blending technology for coal-derived oils, development of new reforming catalysts, technology of heterocompound separation, and the development of applications. Reported in relation with the development of environmentally friendly coal liquefaction technology are the study of coal liquefaction conditions, study of the upgrading of basic liquefaction techniques for the improvement and rationalization of the liquefaction process, and a project of liquefaction technology internationalization. A report is also given on a liquefaction catalyst study meeting. At the 2nd meeting, reports are delivered on the development of environmentally friendly coal liquefaction technology, including a briefing on the situation in general, designing of highly active catalysts, elucidation of the mechanism of emergence of activity, achievement of the marginal yield of coal-derived oils, and the properties of catalyst attached to coal. Delivered in relation with the use of coal-derived oils and technology for their refining are a briefing on the situation in general and reports on the blockup to occur in the naphtha fraction process and measures to counter the problem, control of the metamorphosis of active metals in reaction, heterocompound separation technology, and the development of applications. (NEDO)

  7. Probabilistic versus deterministic hazard assessment in liquefaction susceptible zones

    Science.gov (United States)

    Daminelli, Rosastella; Gerosa, Daniele; Marcellini, Alberto; Tento, Alberto

    2015-04-01

    Probabilistic seismic hazard assessment (PSHA), usually adopted in the framework of seismic codes redaction, is based on Poissonian description of the temporal occurrence, negative exponential distribution of magnitude and attenuation relationship with log-normal distribution of PGA or response spectrum. The main positive aspect of this approach stems into the fact that is presently a standard for the majority of countries, but there are weak points in particular regarding the physical description of the earthquake phenomenon. Factors like site effects, source characteristics like duration of the strong motion and directivity that could significantly influence the expected motion at the site are not taken into account by PSHA. Deterministic models can better evaluate the ground motion at a site from a physical point of view, but its prediction reliability depends on the degree of knowledge of the source, wave propagation and soil parameters. We compare these two approaches in selected sites affected by the May 2012 Emilia-Romagna and Lombardia earthquake, that caused widespread liquefaction phenomena unusually for magnitude less than 6. We focus on sites liquefiable because of their soil mechanical parameters and water table level. Our analysis shows that the choice between deterministic and probabilistic hazard analysis is strongly dependent on site conditions. The looser the soil and the higher the liquefaction potential, the more suitable is the deterministic approach. Source characteristics, in particular the duration of strong ground motion, have long since recognized as relevant to induce liquefaction; unfortunately a quantitative prediction of these parameters appears very unlikely, dramatically reducing the possibility of their adoption in hazard assessment. Last but not least, the economic factors are relevant in the choice of the approach. The case history of 2012 Emilia-Romagna and Lombardia earthquake, with an officially estimated cost of 6 billions

  8. Two-Stage Series-Resonant Inverter

    Science.gov (United States)

    Stuart, Thomas A.

    1994-01-01

    Two-stage inverter includes variable-frequency, voltage-regulating first stage and fixed-frequency second stage. Lightweight circuit provides regulated power and is invulnerable to output short circuits. Does not require large capacitor across ac bus, like parallel resonant designs. Particularly suitable for use in ac-power-distribution system of aircraft.

  9. Ground motions estimates for a cascadia earthquake from liquefaction evidence

    Science.gov (United States)

    Dickenson, S.E.; Obermeier, S.F.

    1998-01-01

    Paleoseismic studies conducted in the coastal regions of the Pacific Northwest in the past decade have revealed evidence of crustal downdropping and subsequent tsunami inundation, attributable to a large earthquake along the Cascadia subduction zone which occurred approximately 300 years ago, and most likely in 1700 AD. In order to characterize the severity of ground motions from this earthquake, we report on results of a field search for seismically induced liquefaction features. The search was made chiefly along the coastal portions of several river valleys in Washington, rivers along the central Oregon coast, as well as on islands in the Columbia River of Oregon and Washington. In this paper we focus only on the results of the Columbia River investigation. Numerous liquefaction features were found in some regions, but not in others. The regional distribution of liquefaction features is evaluated as a function of geologic and geotechnical factors at each site in order to estimate the intensity of ground shaking.

  10. Motor fuels made by direct liquefaction of coal, peat and biomass. Drivmedel genom direktfoervaetskning av kol, torv och biomassa

    Energy Technology Data Exchange (ETDEWEB)

    Granath, L; Karlsson, G; Karlsson, G; Nilsson, T

    1981-01-01

    The Department of Chemical Technology at the Royal Institute of Technology has completed a system study concerning direct liquefaction of peat and biomass to produce transportation fuel. A comprehensive survey of coal liquefaction is included. Gasoline produced in Sweden from direct liquefaction of imported coal may compete with regular gasoline at the earliest around 1985. Biomass can become a competitive alternative to black coal at the beginning of the 21st century. Methanol can be produced from wood with a higher efficiency than the transportation fuels which are produced by direct liquefaction. The peat is not good source for liquefaction as wood chips. A continuously working liquefaction plant designed also for peat among other substances is under construction at the Royal Institute of Technology, Stockholm.

  11. Two-stage anaerobic digestion of cheese whey

    Energy Technology Data Exchange (ETDEWEB)

    Lo, K V; Liao, P H

    1986-01-01

    A two-stage digestion of cheese whey was studied using two anaerobic rotating biological contact reactors. The second-stage reactor receiving partially treated effluent from the first-stage reactor could be operated at a hydraulic retention time of one day. The results indicated that two-stage digestion is a feasible alternative for treating whey. 6 references.

  12. Advanced direct liquefaction concepts for PETC generic units. Quarterly technical progress report, January--March 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-01

    In the Advance Coal Liquefaction Concept Proposal (ACLCP) carbon monoxide (CO) and water have been proposed as the primary reagents in the pretreatment process. The main objective of this project is to develop a methodology for pretreating coal under mild conditions based on a combination of existing processes which have shown great promise in liquefaction, extraction and pyrolysis studies. The aim of this pretreatment process is to partially depolymerise the coal, eliminate oxygen and diminish the propensity for retograde reactions during subsequent liquefaction. The desirable outcome of the CO pretreatment step should be: (1) enhanced liquefaction activity and/or selectivity toward products of higher quality due to chemical modification of the coal structure; (2) cleaner downstream products; (3) overall improvement in operability and process economics.

  13. On the robustness of two-stage estimators

    KAUST Repository

    Zhelonkin, Mikhail

    2012-04-01

    The aim of this note is to provide a general framework for the analysis of the robustness properties of a broad class of two-stage models. We derive the influence function, the change-of-variance function, and the asymptotic variance of a general two-stage M-estimator, and provide their interpretations. We illustrate our results in the case of the two-stage maximum likelihood estimator and the two-stage least squares estimator. © 2011.

  14. Sensitivity Analysis in Two-Stage DEA

    Directory of Open Access Journals (Sweden)

    Athena Forghani

    2015-07-01

    Full Text Available Data envelopment analysis (DEA is a method for measuring the efficiency of peer decision making units (DMUs which uses a set of inputs to produce a set of outputs. In some cases, DMUs have a two-stage structure, in which the first stage utilizes inputs to produce outputs used as the inputs of the second stage to produce final outputs. One important issue in two-stage DEA is the sensitivity of the results of an analysis to perturbations in the data. The current paper looks into combined model for two-stage DEA and applies the sensitivity analysis to DMUs on the entire frontier. In fact, necessary and sufficient conditions for preserving a DMU's efficiency classiffication are developed when various data changes are applied to all DMUs.

  15. Sensitivity Analysis in Two-Stage DEA

    Directory of Open Access Journals (Sweden)

    Athena Forghani

    2015-12-01

    Full Text Available Data envelopment analysis (DEA is a method for measuring the efficiency of peer decision making units (DMUs which uses a set of inputs to produce a set of outputs. In some cases, DMUs have a two-stage structure, in which the first stage utilizes inputs to produce outputs used as the inputs of the second stage to produce final outputs. One important issue in two-stage DEA is the sensitivity of the results of an analysis to perturbations in the data. The current paper looks into combined model for two-stage DEA and applies the sensitivity analysis to DMUs on the entire frontier. In fact, necessary and sufficient conditions for preserving a DMU's efficiency classiffication are developed when various data changes are applied to all DMUs.

  16. Hydrothermal Liquefaction Treatment Hazard Analysis Report

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Peter P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wagner, Katie A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-12

    Hazard analyses were performed to evaluate the modular hydrothermal liquefaction treatment system. The hazard assessment process was performed in 2 stages. An initial assessment utilizing Hazard Identification and Preliminary Hazards Analysis (PHA) techniques identified areas with significant or unique hazards (process safety-related hazards) that fall outside of the normal operating envelope of PNNL and warranted additional analysis. The subsequent assessment was based on a qualitative What-If analysis. The analysis was augmented, as necessary, by additional quantitative analysis for scenarios involving a release of hazardous material or energy with the potential for affecting the public. The following selected hazardous scenarios received increased attention: •Scenarios involving a release of hazardous material or energy, controls were identified in the What-If analysis table that prevent the occurrence or mitigate the effects of the release. •Scenarios with significant consequences that could impact personnel outside the immediate operations area, quantitative analyses were performed to determine the potential magnitude of the scenario. The set of “critical controls” were identified for these scenarios (see Section 4) which prevent the occurrence or mitigate the effects of the release of events with significant consequences.

  17. Two stage-type railgun accelerator

    International Nuclear Information System (INIS)

    Ogino, Mutsuo; Azuma, Kingo.

    1995-01-01

    The present invention provides a two stage-type railgun accelerator capable of spiking a flying body (ice pellet) formed by solidifying a gaseous hydrogen isotope as a fuel to a thermonuclear reactor at a higher speed into a central portion of plasmas. Namely, the two stage-type railgun accelerator accelerates the flying body spiked from a initial stage accelerator to a portion between rails by Lorentz force generated when electric current is supplied to the two rails by way of a plasma armature. In this case, two sets of solenoids are disposed for compressing the plasma armature in the longitudinal direction of the rails. The first and the second sets of solenoid coils are previously supplied with electric current. After passing of the flying body, the armature formed into plasmas by a gas laser disposed at the back of the flying body is compressed in the longitudinal direction of the rails by a magnetic force of the first and the second sets of solenoid coils to increase the plasma density. A current density is also increased simultaneously. Then, the first solenoid coil current is turned OFF to accelerate the flying body in two stages by the compressed plasma armature. (I.S.)

  18. Development of liquefaction process of coal and biomass in supercritical water; Chorinkaisui wo mochiita sekitan biomass doji ekika process no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nonaka, H.; Matsumura, Y.; Tsutsumi, A.; Yoshida, K. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering; Masuno, Y.; Inaba, A. [National Institute for Resources and Environment, Tsukuba (Japan)

    1996-10-28

    Liquefaction of coal and biomass in supercritical water has been investigated, in which strong solubilization force of supercritical water against hydrocarbons is utilized. Free radicals are formed through the cleavage of covalent bonds in coal under the heating condition at around 400{degree}C during coal liquefaction. It is important to stabilize these unstable intermediate products by hydrogen transfer. On the other hand, hydrogen is not required for the liquefaction of biomass having higher H/C atomic ratio and oxygen content than those of coal. Co-liquefaction of coal and biomass was conducted using supercritical water, in which excess hydrogen from the liquefaction of biomass would be transferred to coal, resulting in the effective liquefaction of coal. Mixture of coal and cellulose was liquefied in supercritical water at 390{degree}C under the pressure of 25 MPa using a semi-continuous reactor, and the results were compared with those from the separate liquefaction of them. The co-liquefaction of coal and cellulose did not show any difference in the residue yield from the separate liquefaction of these, but led to the increased production of compounds with lower molecular weight. The liquefaction was completed in 15 minutes. 5 refs., 3 figs., 3 tabs.

  19. Liquefaction of H2 molecules upon exterior surfaces of carbon nanotube bundles

    International Nuclear Information System (INIS)

    Han, Sang Soo; Kang, Jeung Ku; Lee, Hyuck Mo; Duin, Adri C.T. van; Goddard, William A. III

    2005-01-01

    We have used molecular dynamics simulations to investigate interaction of H 2 molecules on the exterior surfaces of carbon nanotubes (CNTs): single and bundle types. At 80 K and 10 MPa, it is found that charge transfer occurs from a low curvature region to a high curvature region of the deformed CNT bundle, which develops charge polarization only on the deformed structure. The long-range electrostatic interactions of polarized charges on the deformed CNT bundle with hydrogen molecules are observed to induce a high local-ordering of H 2 gas that results in hydrogen liquefaction. Our predicted heat of hydrogen liquefaction on the CNT bundle is 97.6 kcal kg -1 . On the other hand, hydrogen liquefaction is not observed in the CNT of a single type. This is because charge polarization is not developed on the single CNT as it is symmetrically deformed under the same pressure. Consequently, the hydrogen storage capacity on the CNT bundle is much higher due to liquefaction than that on the single CNT. Additionally, our results indicate that it would also be possible to liquefy H 2 gas on a more strongly polarized CNT bundle at temperatures higher than 80 K

  20. Dynamic dielectric properties of a wood liquefaction system using polyethylene glycol and glycerol

    Science.gov (United States)

    Mengchao Zhou; Thomas L. Eberhardt; Bo Cai; Chung-Yun Hse; Hui Pan

    2017-01-01

    Microwave-assisted liquefaction has shown potential for rapid thermal processing of lignocellulosic biomass. The efficiency of microwave heating depends largely on the dielectric properties of the materials being heated. The objective of this study was to investigate the dynamic interactions between microwave energy and the reaction system during the liquefaction of a...

  1. Design, synthesis, and characterization of novel fine-particle, unsupported catalysts for coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Klein, M.T.

    1991-12-30

    The purpose of this work is to investigate the kinetics-assisted design, synthesis and characterization of fme-pardcle, unsupported catalysts for coal liquefaction. The goal is to develop a fundamental understanding of coal catalysis and catalysts that will, in turn, allow for the specification of a novel optimal catalyst for coal liquefaction.

  2. Thermoeconomic optimization of a cryogenic refrigeration cycle for re-liquefaction of the LNG boil-off gas

    Energy Technology Data Exchange (ETDEWEB)

    Sayyaadi, Hoseyn; Babaelahi, M. [Faculty of Mechanical Engineering-Energy Division, K.N. Toosi University of Technology, P.O. Box: 19395-1999, No. 15-19, Pardis Str., Mollasadra Ave., Vanak Sq., Tehran 1999 143344 (Iran)

    2010-09-15

    The development of the liquefaction process for the Liquefied Natural Gas (LNG) boil-off re-liquefaction plants will be addressed to provide an environmentally friendly and cost effective solution for the gas transportation. In this manner, onboard boil-off gas (BOG) re-liquefaction system as a cryogenic refrigeration cycle is utilized in order to re-liquefy the BOG and returns it to the cargo tanks instead of burning it. In this paper, a thermoeconomic optimization of the LNG-BOG liquefaction system is performed. A thermoeconomic model based on energy and exergy analyses and an economic model according to the total revenue requirement (TRR) are developed. Minimizing of the unit cost of the refrigeration effect as a product of BOG re-liquefaction plant is performed using the genetic algorithm. Results of thermoeconomic optimization are compared with corresponding features of the base case system. Finally, sensitivity of the total cost of the system product with respect to the variation of some operating parameters is studied. (author)

  3. Catalytic activity of pyrite for coal liquefaction reaction; Tennen pyrite no shokubai seino ni kansuru kento

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, K.; Kozu, M.; Okada, T.; Kobayashi, M. [Nippon Coal Oil Co. Ltd., Tokyo (Japan)

    1996-10-28

    Since natural pyrite is easy to obtain and cheap as coal liquefaction catalyst, it is to be used for the 150 t/d scale NEDOL process bituminous coal liquefaction pilot plant. NEDO and NCOL have investigated the improvement of catalytic activity of pulverized natural pyrite for enhancing performance and economy of the NEDOL process. In this study, coal liquefaction tests were conducted using natural pyrite catalyst pulverized by dry-type bowl mill under nitrogen atmosphere. Mechanism of catalytic reaction of the natural pyrite was discussed from relations between properties of the catalyst and liquefaction product. The natural pyrite provided an activity to transfer gaseous hydrogen into the liquefaction product. It was considered that pulverized pyrite promotes the hydrogenation reaction of asphaltene because pulverization increases its contact rate with reactant and the amount of active points on its surface. It was inferred that catalytic activity of pyrite is affected greatly by the chemical state of Fe and S on its surface. 3 refs., 4 figs., 1 tab.

  4. Design and analysis of liquefaction process for offshore associated gas resources

    International Nuclear Information System (INIS)

    Li, Q.Y.; Ju, Y.L.

    2010-01-01

    Liquefaction is the key section on floating platform. Some experts and designers selected mixed refrigerant process for floating platform, while some recommended expander cycle. However, few of them compared the two types of processes systemically before making a choice. In this paper, the liquefaction processes of propane pre-cooled mixed refrigerant cycle (C 3 /MRC), mixed refrigerant cycle (MRC) and nitrogen expander cycle (N 2 expander) for the special offshore associated gases in South China Sea have been designed and studied. These processes have been analyzed and compared systematically considering the main factors including the performance parameters, economic performance, layout, sensitivity to motion, suitability to different gas resources, safety and operability, accounting for the features of the floating production, storage and offloading unit for liquefied natural gas (LNG-FPSO) in marine environment. The results indicated that N 2 expander has higher energy consumption and poorer economic performance, while it has much more advantages than C 3 /MRC and MRC for offshore application because it is simpler and more compact and thus requiring less deck area, less sensitive to LNG-FPSO motion, has better suitability for other gas resources, has higher safety and is easier to operate. Therefore, N 2 expander is the most suitable offshore liquefaction process. In addition, the exergy analysis is conducted for N 2 expander and the results indicate that the compression equipments and after coolers, expanders and LNG heat exchangers are the main contribution to the total exergy losses. The measures to decrease the losses for these equipments are then discussed.

  5. Direct liquefaction of low-rank coals under mild conditions

    Energy Technology Data Exchange (ETDEWEB)

    Braun, N.; Rinaldi, R. [Max-Planck-Institut fuer Kohlenforschung, Muelheim an der Ruhr (Germany)

    2013-11-01

    Due to decreasing of petroleum reserves, direct coal liquefaction is attracting renewed interest as an alternative process to produce liquid fuels. The combination of hydrogen peroxide and coal is not a new one. In the early 1980, Vasilakos and Clinton described a procedure for desulfurization by leaching coal with solutions of sulphuric acid/H{sub 2}O{sub 2}. But so far, H{sub 2}O{sub 2} has never been ascribed a major role in coal liquefaction. Herein, we describe a novel approach for liquefying low-rank coals using a solution of H{sub 2}O{sub 2} in presence of a soluble non-transition metal catalyst. (orig.)

  6. Life cycle assessment of bio-jet fuel from hydrothermal liquefaction of microalgae

    International Nuclear Information System (INIS)

    Fortier, Marie-Odile P.; Roberts, Griffin W.; Stagg-Williams, Susan M.; Sturm, Belinda S.M.

    2014-01-01

    Highlights: • A life cycle assessment of bio-jet fuel from wastewater algae was performed. • We used experimental data from algae cultivation through hydrothermal liquefaction. • We performed Monte Carlo and sensitivity analyses with ranges of parameter values. • Transport of moderately dewatered algae increased life cycle climate change impacts. • Collocation and heat integration reduce life cycle greenhouse gas emissions by 76%. - Abstract: Bio-jet fuel is increasingly being produced from feedstocks such as algae and tested in flight. As the industry adopts bio-jet fuels from various feedstocks and conversion processes, life cycle assessment (LCA) is necessary to determine whether these renewable fuels result in lower life cycle greenhouse gas (LC-GHG) emissions than conventional jet fuel. An LCA was performed for a functional unit of 1 GJ of bio-jet fuel produced through thermochemical conversion (hydrothermal liquefaction (HTL)) of microalgae cultivated in wastewater effluent. Two pathways were analyzed to compare the impacts of siting HTL at a wastewater treatment plant (WWTP) to those of siting HTL at a refinery. Base cases for each pathway were developed in part using primary data from algae production in wastewater effluent and HTL experiments of this algae at the University of Kansas. The LC-GHG emissions of these cases were compared to those of conventional jet fuel, and a sensitivity analysis and Monte Carlo analyses were performed. When algal conversion using HTL was modeled at a refinery versus at the WWTP site, the transportation steps of biomass and waste nutrients were major contributors to the LC-GHG emissions of algal bio-jet fuel. The LC-GHG emissions were lower for the algal bio-jet fuel pathway that performs HTL at a WWTP (35.2 kg CO 2eq /GJ for the base case) than for the pathway for HTL at a refinery (86.5 kg CO 2eq /GJ for the base case). The LCA results were particularly sensitive to the extent of heat integration, the source of

  7. Quaternary Geology and Liquefaction Susceptibility, Napa, California 1:100,000 Quadrangle: A Digital Database

    Science.gov (United States)

    Sowers, Janet M.; Noller, Jay S.; Lettis, William R.

    1998-01-01

    Earthquake-induced ground failures such as liquefaction have historically brought loss of life and damage to property and infrastructure. Observations of the effects of historical large-magnitude earthquakes show that the distribution of liquefaction phenomena is not random. Liquefaction is restricted to areas underlain by loose, cohesionless sands and silts that are saturated with water. These areas can be delineated on the basis of thorough geologic, geomorphic, and hydrologic mapping and map analysis (Tinsley and Holzer, 1990; Youd and Perkins, 1987). Once potential liquefaction zones are delineated, appropriate public and private agencies can prepare for and mitigate seismic hazard in these zones. In this study, we create a liquefaction susceptibility map of the Napa 1:100,000 quadrangle using Quaternary geologic mapping, analysis of historical liquefaction information, groundwater data, and data from other studies. The study is atterned after state-of-the-art studies by Youd (1973) Dupre and Tinsley (1980) and Dupre (1990) in the Monterey-Santa Cruz area, Tinsley and others (1985) in the Los Angeles area, and Youd and Perkins (1987) in San Mateo County, California. The study area comprises the northern San Francisco Metropolitan Area, including the cities of Santa Rosa, Vallejo, Napa, Novato, Martinez, and Fairfield (Figure 1). Holocene estuarine deposits, Holocene stream deposits, eolian sands, and artificial fill are widely present in the region (Helley and Lajoie, 1979) and are the geologic materials of greatest concern. Six major faults capable of producing large earthquakes cross the study area, including the San Andreas, Rodgers Creek, Hayward, West Napa, Concord, and Green Valley faults (Figure 1).

  8. A new boil-off gas re-liquefaction system for LNG carriers based on dual mixed refrigerant cycle

    Science.gov (United States)

    Tan, Hongbo; Shan, Siyu; Nie, Yang; Zhao, Qingxuan

    2018-06-01

    A new boil-off gas (BOG) re-liquefaction system for LNG carriers has been proposed to improve the system energy efficiency. Two cascade mixed refrigerant cycles (or dual mixed refrigerant cycle, DMR) are used to provide the cooling capacity for the re-liquefaction of BOG. The performance of the new system is analysed on the basis of the thermodynamic data obtained in the process simulation in Aspen HYSYS software. The results show that the power consumed in the BOG compressor and the high-temperature mixed refrigerant compressor could be saved greatly due to the reduced mass flow rates of the processed fluids. Assuming the re-liquefaction capacity of the investigated system is 4557.6 kg/h, it is found that the total power consumption can be reduced by 25%, from 3444 kW in the existing system to 2585.8 kW in the proposed system. The coefficient of performance (COP) of 0.25, exergy efficiency of 41.3% and the specific energy consumption (SEC) of 0.589 kWh/kg(LNG) could be achieved in the new system. It exhibits 33% of improvement in the COP and exergy efficiency in comparison with the corresponding values of the existing system. It indicates that employing the DMR based BOG re-liquefaction system could improve the system energy efficiency of LNG carriers substantially.

  9. Two-step two-stage fission gas release model

    International Nuclear Information System (INIS)

    Kim, Yong-soo; Lee, Chan-bock

    2006-01-01

    Based on the recent theoretical model, two-step two-stage model is developed which incorporates two stage diffusion processes, grain lattice and grain boundary diffusion, coupled with the two step burn-up factor in the low and high burn-up regime. FRAPCON-3 code and its in-pile data sets have been used for the benchmarking and validation of this model. Results reveals that its prediction is in better agreement with the experimental measurements than that by any model contained in the FRAPCON-3 code such as ANS 5.4, modified ANS5.4, and Forsberg-Massih model over whole burn-up range up to 70,000 MWd/MTU. (author)

  10. Two-stage revision of septic knee prosthesis with articulating knee spacers yields better infection eradication rate than one-stage or two-stage revision with static spacers.

    Science.gov (United States)

    Romanò, C L; Gala, L; Logoluso, N; Romanò, D; Drago, L

    2012-12-01

    The best method for treating chronic periprosthetic knee infection remains controversial. Randomized, comparative studies on treatment modalities are lacking. This systematic review of the literature compares the infection eradication rate after two-stage versus one-stage revision and static versus articulating spacers in two-stage procedures. We reviewed full-text papers and those with an abstract in English published from 1966 through 2011 that reported the success rate of infection eradication after one-stage or two-stage revision with two different types of spacers. In all, 6 original articles reporting the results after one-stage knee exchange arthoplasty (n = 204) and 38 papers reporting on two-stage revision (n = 1,421) were reviewed. The average success rate in the eradication of infection was 89.8% after a two-stage revision and 81.9% after a one-stage procedure at a mean follow-up of 44.7 and 40.7 months, respectively. The average infection eradication rate after a two-stage procedure was slightly, although significantly, higher when an articulating spacer rather than a static spacer was used (91.2 versus 87%). The methodological limitations of this study and the heterogeneous material in the studies reviewed notwithstanding, this systematic review shows that, on average, a two-stage procedure is associated with a higher rate of eradication of infection than one-stage revision for septic knee prosthesis and that articulating spacers are associated with a lower recurrence of infection than static spacers at a comparable mean duration of follow-up. IV.

  11. Influence of the void ratio and the confining on the static liquefaction in slopes in shangi sand

    Directory of Open Access Journals (Sweden)

    Alfonso Mariano Ramos Cañón

    2015-01-01

    Full Text Available A numerical study on the onset of static liquefaction in slopes under undrained conditions of loading was developed based on a general liquefaction flow instability criterion for elastoplastic soils based on the concept of loss of controllability. The criterion is applied to the case of axisymmetric loading to detect the onset of static liquefaction. The criterion is used in conjunction with an elastoplastic model for sands and is tested by means of numerical simulations of element tests. The numerical results are compared with experimental evidence obtaining good agreement. A quantitative study of the influence of the mean pressure, void ratio and the anisotropy of stress on the onset of static liquefaction is presented for the Changi sand. From the analysis of the numerical results, it can be concluded that: a. the mobilized friction angle at the onset of liquefaction is not an intrinsic property of the material, but is a state variable b. Despite of the multiple variables involved in the process of generation of undrained instability, the state of stresses at the onset of static liquefaction can be conveniently represented by a linear relation between Dq/po and no . This graphical representation can be used in the practice of geotechnical engineering to quantify the margin of security against the static liquefaction of a sandy slope.

  12. Two stages of economic development

    OpenAIRE

    Gong, Gang

    2016-01-01

    This study suggests that the development process of a less-developed country can be divided into two stages, which demonstrate significantly different properties in areas such as structural endowments, production modes, income distribution, and the forces that drive economic growth. The two stages of economic development have been indicated in the growth theory of macroeconomics and in the various "turning point" theories in development economics, including Lewis's dual economy theory, Kuznet...

  13. Economically viable large-scale hydrogen liquefaction

    Science.gov (United States)

    Cardella, U.; Decker, L.; Klein, H.

    2017-02-01

    The liquid hydrogen demand, particularly driven by clean energy applications, will rise in the near future. As industrial large scale liquefiers will play a major role within the hydrogen supply chain, production capacity will have to increase by a multiple of today’s typical sizes. The main goal is to reduce the total cost of ownership for these plants by increasing energy efficiency with innovative and simple process designs, optimized in capital expenditure. New concepts must ensure a manageable plant complexity and flexible operability. In the phase of process development and selection, a dimensioning of key equipment for large scale liquefiers, such as turbines and compressors as well as heat exchangers, must be performed iteratively to ensure technological feasibility and maturity. Further critical aspects related to hydrogen liquefaction, e.g. fluid properties, ortho-para hydrogen conversion, and coldbox configuration, must be analysed in detail. This paper provides an overview on the approach, challenges and preliminary results in the development of efficient as well as economically viable concepts for large-scale hydrogen liquefaction.

  14. FY 1980 Report on results of Sunshine Project. Development of coal liquefaction techniques (Development of materials for the coal liquefaction plant); 1980 nendo sekitan ekika gijutsu no kaihatsu seika hokokusho. Sekitan ekika plant zairyo no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    A 1 T/D solvent-extraction type coal liquefaction test plant was constructed and operated to obtain the technical data for the design of, and establish the techniques for, an efficient coal liquefaction plant. The FY 1980 program includes surveys on the materials for coal liquefaction plants, covering those already developed and under development, to clarify the problematical points; drafting the test schedules; and conceptual designs of the material testing facilities. The major problems involved in the materials for coal liquefaction plants include erosion by fluidizing coal slurry, hydrogen embrittlement of the reactor materials, and corrosion by the liquefaction products (e.g., stress-corrosion cracking of austenitic steel, and corrosion by organic acids). The surveys on materials research trends suggest that USA seems to concentrate their research efforts on the reactor materials. The corrosion tests are mostly of in-plant tests, but the stress corrosion and slurry erosion tests are conducted on a laboratory scale. The conceptual designs are drawn for some testing units, e.g., the loop type material testing unit and basic testing unit for jet-spray type slurry erosion. (NEDO)

  15. Thermodynamic analysis of hydrocarbon refrigerants-based ethylene BOG re-liquefaction system

    Science.gov (United States)

    Beladjine, Boumedienne M.; Ouadha, Ahmed; Addad, Yacine

    2016-09-01

    The present study aims to make a thermodynamic analysis of an ethylene cascade re-liquefaction system that consists of the following two subsystems: a liquefaction cycle using ethylene as the working fluid and a refrigeration cycle operating with a hydrocarbon refrigerant. The hydrocarbon refrigerants considered are propane (R290), butane (R600), isobutane (R600a), and propylene (R1270). A computer program written in FORTRAN is developed to compute parameters for characteristic points of the cycles and the system's performance, which is determined and analyzed using numerical solutions for the refrigerant condensation temperature, temperature in tank, and temperature difference in the cascade condenser. Results show that R600a gives the best performance, followed by (in order) R600, R290, and R1270. Furthermore, it is found that an increase in tank temperature improves system performance but that an increase in refrigerant condensation temperature causes deterioration. In addition, it is found that running the system at a low temperature difference in the cascade condenser is advantageous.

  16. Scrum integration in stage-gate models for collaborative product development

    DEFF Research Database (Denmark)

    Sommer, Anita Friis; Slavensky, Andreas; Nguyen, Vivi Thuy

    2013-01-01

    to differentiate from low-cost competitors and increase PD performance, some industrial manufacturers now seek competitive advantage by experimenting with new ways for collaborative PD. This includes integrating customer-focused agile process models, like Scrum, from the software industry into their existing PD...... models. Thus, instead of replacing traditional stage-gate models agile methods are currently integrated in existing PD models generating hybrid solution for collaborative PD. This paper includes a study of three industrial cases that have successfully integrated Scrum into a stage-gate process model...

  17. Novel use of residue from direct coal liquefaction process

    Energy Technology Data Exchange (ETDEWEB)

    Jianli Yang; Zhaixia Wang; Zhenyu Liu; Yuzhen Zhang [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion

    2009-09-15

    Direct coal liquefaction residue (DCLR) is, commonly, designed to be used as a feed stock for gasification or combustion. Use of DCLR as a value added product is very important for improving overall economy of direct coal liquefaction processes. This study shows that the DCLR may be used as a pavement asphalt modifier. The modification ability is similar to that of Trinidad Lake Asphalt (TLA), a superior commercial modifier. Asphalts modified by two DCLRs meet the specifications of ASTM D5710 and BSI BS-3690 designated for the TLA-modified asphalts. The required addition amount for the DCLRs tested is less than that for TLA due possibly to the high content of asphaltene in DCLRs. Different compatibility was observed for the asphalts with the same penetration grade but from the different origin. Different components in the DCLR play different roles in the modification. Positive synergetic effects among the fractions were observed, which may due to the formation of the stable colloid structure. Unlike polymer-type modifier, the structure of asphalt-type modifier has a similarity with petroleum asphalts which favors the formation of a stable dispersed polar fluid (DPF) colloid structure and improves the performance of pavement asphalt. 12 refs., 1 fig., 6 tabs.

  18. Hydrothermal Liquefaction of the Microalgae Phaeodactylum tricornutum

    DEFF Research Database (Denmark)

    Sigaard Christensen, Per; Peng, Gaël; Vogel, Frédéric

    2014-01-01

    The microalgae Phaeodactylum tricornutum was processed by hydrothermal liquefaction in order to assess the influence of reaction temperature and reaction time on the product and elemental distribution. The experiments were carried out at different reaction times (5 and 15 min) and over a wide range...

  19. The making of Andersen’s liquefaction chart

    DEFF Research Database (Denmark)

    Sabaliauskas, Tomas; Ibsen, Lars Bo

    Andersen’s chart (Andersen & Berre, 1999) is a graphical method of observing cyclic soil response. It allows observing soil response to various stress amplitudes that can lead to liquefaction, excess plastic deformation stabilizing soil response.The process of obtaining the original chart has been...

  20. Report on the achievements in the Sunshine Project in fiscal 1987. Collection of data from coal liquefaction processes, and development of a disposal system; 1987 nendo sekitan ekika process nado no data no shushu, shori system nado no kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-03-01

    The present study is intended to investigate the current status of the information control system in the coal liquefaction technology development project, and structure a coal liquefaction database system to manage and utilize comprehensively the items of information provided by the system. Section 2 shows the result of epitomizing opinions on the purpose of the coal liquefaction database by means of a questionnaire survey to NEDO, and opinions of people of experience and academic standing. Section 3 depicts the basic conception of a coal database total system. Section 4 summarizes the conceptual idea of the fundamental database by washing out the data input and output, and the contents recorded in the database. Section 5 summarizes the basic sub-system required for management and utilization of the database, and different application systems for data analysis required in each stage of performing the coal liquefaction technology development, and for operation assistance. Section 6 summarizes a general technological information retrieval system, in which general information on coal liquefaction is recorded, processed, and registered and accumulated in the database, and then the information retrieval and the original information providing service are carried out. Section 7 summarizes philosophies on development and operation of the coal liquefaction database, operating institutions, and problems to be solved. (NEDO)

  1. A cause and effect two-stage BSC-DEA method for measuring the relative efficiency of organizations

    Directory of Open Access Journals (Sweden)

    Seyed Esmaeel Najafi

    2011-01-01

    Full Text Available This paper presents an integration of balanced score card (BSE with two-stage data envelopment analysis (DEA. The proposed model of this paper uses different financial and non-financial perspectives to evaluate the performance of decision making units in different BSC stages. At each stage, a two-stage DEA method is implemented to measure the relative efficiency of decision making units and the results are monitored using the cause and effect relationships. An empirical study for a banking sector is also performed using the method developed in this paper and the results are briefly analyzed.

  2. Effective conversion of maize straw wastes into bio-hydrogen by two-stage process integrating H2 fermentation and MECs.

    Science.gov (United States)

    Li, Yan-Hong; Bai, Yan-Xia; Pan, Chun-Mei; Li, Wei-Wei; Zheng, Hui-Qin; Zhang, Jing-Nan; Fan, Yao-Ting; Hou, Hong-Wei

    2015-12-01

    The enhanced H2 production from maize straw had been achieved through the two-stage process of integrating H2 fermentation and microbial electrolysis cells (MECs) in the present work. Several key parameters affecting hydrolysis of maize straw through subcritical H2O were optimized by orthogonal design for saccharification of maize straw followed by H2 production through H2 fermentation. The maximum reducing sugar (RS) content of maize straw reached 469.7 mg/g-TS under the optimal hydrolysis condition with subcritical H2O combining with dilute HCl of 0.3% at 230 °C. The maximum H2 yield, H2 production rate, and H2 content was 115.1 mL/g-TVS, 2.6 mL/g-TVS/h, and 48.9% by H2 fermentation, respectively. In addition, the effluent from H2 fermentation was used as feedstock of MECs for additional H2 production. The maximum H2 yield of 1060 mL/g-COD appeared at an applied voltage of 0.8 V, and total COD removal reached about 35%. The overall H2 yield from maize straw reached 318.5 mL/g-TVS through two-stage processes. The structural characterization of maize straw was also carefully investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) spectra.

  3. Numerical simulation of liquefaction behaviour of granular materials ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    cles using Discrete Element Method (DEM) is used to study the liquefaction behaviour of ... studies have focussed on the stress-strain relation- ... experimentation still remains quite problematic. ... distorting the periodic cell and changing its vol-.

  4. Whole Algae Hydrothermal Liquefaction: 2014 State of Technology

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Susanne B.; Zhu, Yunhua; Snowden-Swan, Lesley J.; Anderson, Daniel; Hallen, Richard T.; Schmidt, Andrew J.; Albrecht, Karl O.; Elliott, Douglas C.

    2014-07-30

    This report describes the base case yields and operating conditions for converting whole microalgae via hydrothermal liquefaction and upgrading to liquid fuels. This serves as the basis against which future technical improvements will be measured.

  5. Catalytic subcritical water liquefaction of flax straw for high yield of furfural

    International Nuclear Information System (INIS)

    Harry, Inibehe; Ibrahim, Hussameldin; Thring, Ron; Idem, Raphael

    2014-01-01

    There is substantial interest in the application of biomass as a renewable fuel or for production of chemicals. Flax straw can be converted into valuable chemicals and biofuels via liquefaction in sub-critical water. In this study, the yield of furfural and the kinetics of flax straw liquefaction under sub-critical water conditions were investigated using a high-pressure autoclave reactor. The liquefaction was conducted in the temperature range of 175–325 °C, pressure of 0.1 MPa–8 MPa, retention time in the range of 0 min–120 min, and flax straw mass fraction (w F ) of 5–20 %. Also, the effect of acid catalysts on furfural yield was studied. The kinetic parameters of flax straw liquefaction were determined using nonlinear regression of the experimental data, assuming second-order kinetics. The apparent activation energy was found to be 27.97 kJ mol −1 while the reaction order was 2.0. The optimum condition for furfural yield was at 250 °C, 6.0 MPa, w F of 5% and 0 retention time after reaching set conditions. An acid catalyst was found to selectively favour furfural yield with 40% flax straw conversion. - Highlights: • Flax straw liquefaction in subcritical water. • Creation of a reaction pathway that can be used to optimized furfural production. • Acid catalyst selectively favoured furfural yield with respect to other liquid products. • At the highest process temperature of 325 °C, a carbon conversion of 40% was achieved. • Activation energy and reaction order was 28 kJ/mol and 2.0 respectively

  6. Fiscal 1991 report on the brown coal liquefaction section meeting; 1991 nendo kattan ekika bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-03-01

    At the 1st through 5th brown coal liquefaction group meetings held for the fiscal year, reports are delivered and discussions are made about the progress of research and development. At the 1st meeting, a fiscal 1991 brown coal liquefaction research plan is introduced, and discussed. At the 2nd meeting, an interim report on the brown coal liquefaction technology development project is discussed. At the 3rd meeting (a joint meeting of the brown coal and bituminous coal liquefaction groups), an agendum entitled 'what the development of brown/bituminous coal liquefaction technologies for the 21st century should be' is reported, and discussed. At the 4th meeting, reports are made on the results of deliberation at the Industrial Technology Council, progress of the follow-up study, progress of the collection of achievements, and so forth. At the 5th meeting, the outline of the follow-up study, the collection of achievements in the pilot plant study (a project report preparation schedule and materials evaluation), the progress of pilot plant dismantling work, etc., are reported and discussed. (NEDO)

  7. Fiscal 1991 report on the brown coal liquefaction section meeting; 1991 nendo kattan ekika bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-03-01

    At the 1st through 5th brown coal liquefaction group meetings held for the fiscal year, reports are delivered and discussions are made about the progress of research and development. At the 1st meeting, a fiscal 1991 brown coal liquefaction research plan is introduced, and discussed. At the 2nd meeting, an interim report on the brown coal liquefaction technology development project is discussed. At the 3rd meeting (a joint meeting of the brown coal and bituminous coal liquefaction groups), an agendum entitled 'what the development of brown/bituminous coal liquefaction technologies for the 21st century should be' is reported, and discussed. At the 4th meeting, reports are made on the results of deliberation at the Industrial Technology Council, progress of the follow-up study, progress of the collection of achievements, and so forth. At the 5th meeting, the outline of the follow-up study, the collection of achievements in the pilot plant study (a project report preparation schedule and materials evaluation), the progress of pilot plant dismantling work, etc., are reported and discussed. (NEDO)

  8. Liquefaction analysis of alluvial soil deposits in Bedsa south west of Cairo

    Directory of Open Access Journals (Sweden)

    Kamal Mohamed Hafez Ismail Ibrahim

    2014-09-01

    Full Text Available Bedsa is one of the districts in Dahshour that lays south west of Cairo and suffered from liquefaction during October 1992 earthquake, Egypt. The soil profile consists of alluvial river Nile deposits mainly sandy mud with low plasticity; the ground water is shallow. The earthquake hypocenter was 18 km far away with local magnitude 5.8; the fault length was 13.8 km, as recorded by the Egyptian national seismological network (ENSN at Helwan. The analysis used the empirical method introduced by the national center for earthquake engineering research (NCEER based on field standard penetration of soil. It is found that the studied area can liquefy since there are saturated loose sandy silt layers at depth ranges from 7 to 14 m. The settlement is about 26 cm. The probability of liquefaction ranges between 40% and 100%. The presence of impermeable surface from medium cohesive silty clay acts as a plug resisting and trapping the upward flow of water during liquefaction, so fountain and spouts at weak points occurs. It is wise to use point bearing piles with foundation level deeper than 14 m beyond the liquefiable depth away from ground slopes, otherwise liquefaction improving techniques have to be applied in the area.

  9. Fiscal 1993 report. Coal liquefaction committee; 1993 nendo sekitan ekika iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    The committee in this fiscal year had the 1st meeting in July 1993, the 2nd in December 1993, and the 3rd in March 1994, when fiscal 1993 research and development programs and results were reported and discussed. Reported and discussed at the 2nd meeting were the compilation of brown coal liquefaction technology development project results, evaluation report on the same, hydrorefining of oil from brown coal and the research and development of application technologies for the same, and an environmental safety evaluation test on the same. In selecting a standard coal for the operation of the 150 ton/day pilot plant, PSU (process supporting unit)-aided studies were made on the analytical values presented by coals, yield of the liquid, yield of the liquefaction residue, yield of the generated gas, amount of the hydrogen consumed, coal oil properties, liquefaction residue properties, operationality, etc. On-site investigations were conducted also in Indonesia, and a conclusion was reached that Tanito Harum coal would be the most suitable for the pilot plant. Concerning the liquefaction catalyst for the pilot plant, a report was given on a comparison made between the activity of a synthetic iron sulfide and that of natural pyrite. (NEDO)

  10. Cooperative research program in coal liquefaction. Quarterly report, May 1, 1993--October 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, G.P. [ed.

    1994-07-01

    This report summarizes progress in four areas of research under the general heading of Coal Liquefaction. Results of studies concerning the coliquefaction of coal with waste organic polymers or chemical products of these polymers were reported. Secondly, studies of catalytic systems for the production of clean transportation fuels from coal were discussed. Thirdly, investigations of the chemical composition of coals and their dehydrogenated counterparts were presented. These studies were directed toward elucidation of coal liquefaction processes on the chemical level. Finally, analytical methodologies developed for in situ monitoring of coal liquefaction were reported. Techniques utilizing model reactions and methods based on XAFS, ESR, and GC/MS are discussed.

  11. Liquefaction of Semen Generates and Later Degrades a Conserved Semenogelin Peptide That Enhances HIV Infection

    Science.gov (United States)

    Liu, Haichuan; Usmani, Shariq M.; Neidleman, Jason; Müller, Janis A.; Avila-Herrera, Aram; Gawanbacht, Ali; Zirafi, Onofrio; Chu, Simon; Dong, Ming; Kumar, Senthil T.; Smith, James F.; Pollard, Katherine S.; Fändrich, Marcus; Kirchhoff, Frank; Münch, Jan; Witkowska, H. Ewa; Greene, Warner C.

    2014-01-01

    ABSTRACT Semen enhances HIV infection in vitro, but how long it retains this activity has not been carefully examined. Immediately postejaculation, semen exists as a semisolid coagulum, which then converts to a more liquid form in a process termed liquefaction. We demonstrate that early during liquefaction, semen exhibits maximal HIV-enhancing activity that gradually declines upon further incubation. The decline in HIV-enhancing activity parallels the degradation of peptide fragments derived from the semenogelins (SEMs), the major components of the coagulum that are cleaved in a site-specific and progressive manner upon initiation of liquefaction. Because amyloid fibrils generated from SEM fragments were recently demonstrated to enhance HIV infection, we set out to determine whether any of the liquefaction-generated SEM fragments associate with the presence of HIV-enhancing activity. We identify SEM1 from amino acids 86 to 107 [SEM1(86-107)] to be a short, cationic, amyloidogenic SEM peptide that is generated early in the process of liquefaction but that, conversely, is lost during prolonged liquefaction due to the activity of serine proteases. Synthetic SEM1(86-107) amyloids directly bind HIV-1 virions and are sufficient to enhance HIV infection of permissive cells. Furthermore, endogenous seminal levels of SEM1(86-107) correlate with donor-dependent variations in viral enhancement activity, and antibodies generated against SEM1(86-107) recognize endogenous amyloids in human semen. The amyloidogenic potential of SEM1(86-107) and its virus-enhancing properties are conserved among great apes, suggesting an evolutionarily conserved function. These studies identify SEM1(86-107) to be a key, HIV-enhancing amyloid species in human semen and underscore the dynamic nature of semen's HIV-enhancing activity. IMPORTANCE Semen, the most common vehicle for HIV transmission, enhances HIV infection in vitro, but how long it retains this activity has not been investigated. Semen

  12. Reducing capital and operating costs in gas processing, liquefaction, and storage

    Energy Technology Data Exchange (ETDEWEB)

    Krusen, III, L C [Phillips Petroleum Co., Bartlesville, OK (United States). Research Div.

    1997-06-01

    The LNG industry is unanimous that capital costs must be reduced throughout the chain, and especially at the liquefaction facility including associated gas processing and LNG storage. The Ken ai LNG plant provides an example of how both reduced capital and operating costs were attained. This paper will cover cost production strategies that can be applied to liquefaction processes in general, and will than focus on their realization in the Phillips Optimized Cascade LNG process. The paper concludes that reduced LNG plant costs are attainable. (Author).

  13. Reducing capital and operating costs in gas processing, liquefaction, and storage

    International Nuclear Information System (INIS)

    Krusen, L.C. III

    1997-01-01

    The LNG industry is unanimous that capital costs must be reduced throughout the chain, and especially at the liquefaction facility including associated gas processing and LNG storage. The Ken ai LNG plant provides an example of how both reduced capital and operating costs were attained. This paper will cover cost production strategies that can be applied to liquefaction processes in general, and will than focus on their realization in the Phillips Optimized Cascade LNG process. The paper concludes that reduced LNG plant costs are attainable. (Author)

  14. Co-Liquefaction of Elbistan Lignite with Manure Biomass; Part 3 - Effect of Reaction Time and Temperature

    Science.gov (United States)

    Koyunoglu, Cemil; Karaca, Hüseyin

    2017-12-01

    Most of the liquefaction process were carried out in a batch reactor, in which the residence time of the liquefaction products is long enough to favour the retrogressive reactions. To minimize retrogressive reactions, the liquefaction of coal was carried out in a flowing solvent reactor in which a fixed bed of coal is continuously permeated by hot solvent. Solvent flowing through the coal bed carries the liquefaction products out of the reactor. Unlike experiments carried out under similar conditions in a batch reactor no increase in solid residue is observed during long time high temperature runs in the flowing solvent reactor. There is a greater appreciation of the importance of retrograde, or polymerization, reactions. If the free radicals formed when coal breaks down are not quickly capped with hydrogen, they react with each other to form large molecules that are much harder to break down than the original coal. Reaction time impacts both the co-liquefaction cost and the product yield. So as to study this idea, the experiments of Elbistan Lignite (EL) with manure co-liquefaction carried out by changing the reaction time from 30 to 120 minutes. As a result, the greatest oil products yields obtained at 60 minutes. Therefore, by thinking about the oil products yield values acquired, the optimal reaction time was obtained to be 60 minutes for Elbistan lignite (EL) with manure liquefied with the temperature of 350°C and 400°C. Above 425°C did not examine because solvent (tetraline) loses its function after 425 °C. The obtained optimum temperature found 400°C due to higher total conversion of liquefaction products and also oil+gas yields.

  15. Accuracy of the One-Stage and Two-Stage Impression Techniques: A Comparative Analysis.

    Science.gov (United States)

    Jamshidy, Ladan; Mozaffari, Hamid Reza; Faraji, Payam; Sharifi, Roohollah

    2016-01-01

    Introduction . One of the main steps of impression is the selection and preparation of an appropriate tray. Hence, the present study aimed to analyze and compare the accuracy of one- and two-stage impression techniques. Materials and Methods . A resin laboratory-made model, as the first molar, was prepared by standard method for full crowns with processed preparation finish line of 1 mm depth and convergence angle of 3-4°. Impression was made 20 times with one-stage technique and 20 times with two-stage technique using an appropriate tray. To measure the marginal gap, the distance between the restoration margin and preparation finish line of plaster dies was vertically determined in mid mesial, distal, buccal, and lingual (MDBL) regions by a stereomicroscope using a standard method. Results . The results of independent test showed that the mean value of the marginal gap obtained by one-stage impression technique was higher than that of two-stage impression technique. Further, there was no significant difference between one- and two-stage impression techniques in mid buccal region, but a significant difference was reported between the two impression techniques in MDL regions and in general. Conclusion . The findings of the present study indicated higher accuracy for two-stage impression technique than for the one-stage impression technique.

  16. [Longjintonglin Capsules for type IIIA prostatitis accompanied by abnormal semen liquefaction: A clinical observation].

    Science.gov (United States)

    Cai, Hong-cai; Wan, Chang-chun; Geng, Qiang; Liu, Wei; Zhang, Guo-wei; Shang, Xue-jun; Huang, Yu-feng

    2016-01-01

    To evaluate the therapeutic effect of Longjintonglin Capsules on type IIIA prostatitis accompanied by abnormal semen liquefaction. We selected 140 patients with type IIIA prostatitis accompanied by abnormal semen liquefaction according to the diagnostic standards of the American Institutes of Health (NIH) and treated them with Longjintonglin Capsules orally 3 capsules once tid for 12 weeks. We obtained the NIH Chronic Prostatitis Symptom Indexes (NIH-CPSI), traditional Chinese medicine (TCM) syndrome scores, leukocyte count in the expressed prostatic secretion (EPS), semen liquefaction time, and the results of semen analysis and compared these indicators before and after the treatment. Of the 140 cases, 132 were included in this study, excluding 8 due to their incomplete case histories. Before and after 4, 8 and 12 weeks of medication, the total NIH-CPSI scores were 24.52 ± 5.43, 21.28 ± 4.85, 18.01 ± 4.28, and 14.49 ± 3.65 (P prostatitis were cured and another 72 well responded, with an overall response rate of 78.0%. Of those with abnormal semen liquefaction, 61 were cured, 39 well responded, and 32 failed to respond, with an overall effectiveness rate of 75.8%. Semen analysis showed significantly increased percentage of progressively motile sperm after 4, 8 and 12 weeks of medication as compared with the baseline (P prostatitis accompanied by abnormal semen liquefaction.

  17. Report on the achievements in the Sunshine Project. A comprehensive report on development of coal liquefaction technologies and a performance test on Chinese coal liquefaction (fiscals 1981 through 1987); Sekitan ekika gijutsu kaihatsu seika hokokusho. Chugokutan ekika seino shiken sogo hokokusho (1981 nendo kara 1987 nendo)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-03-01

    The present Japan-China joint development project is intended to study liquefaction performance of different types of Chinese coals, select coal types suitable for coal liquefaction, and serve for enhancement in the coal liquefaction technologies employed by the Chinese side. Since a small continuous testing device has been installed in fiscal 1982 and begun with the trial operation in March 1983, the liquefaction test has been performed for about five years, and is scheduled to continue another three years. Chinese coals produced in seven provinces and two autonomous regions have been subjected to the coal type selection, on which discussions were given for liquefying reaction characteristics by using autoclave testing and small continuous testing devices. As a result, circulation tests were performed by the end of fiscal 1987 on five coal types, namely Beisu coal, Texgxian coal, Xianfeng coal, Shenmu coal, and Meihekou coal. Data were acquired during the circulation and at the equilibrium. Comparison of the results of tests on these five coal types with the results having been acquired from the 0.1-t/d BSU in Japan before modification verified the result being nearly reasonable. (NEDO)

  18. Comparison of single-stage and temperature-phased two-stage anaerobic digestion of oily food waste

    International Nuclear Information System (INIS)

    Wu, Li-Jie; Kobayashi, Takuro; Li, Yu-You; Xu, Kai-Qin

    2015-01-01

    Highlights: • A single-stage and two two-stage anaerobic systems were synchronously operated. • Similar methane production 0.44 L/g VS_a_d_d_e_d from oily food waste was achieved. • The first stage of the two-stage process became inefficient due to serious pH drop. • Recycle favored the hythan production in the two-stage digestion. • The conversion of unsaturated fatty acids was enhanced by recycle introduction. - Abstract: Anaerobic digestion is an effective technology to recover energy from oily food waste. A single-stage system and temperature-phased two-stage systems with and without recycle for anaerobic digestion of oily food waste were constructed to compare the operation performances. The synchronous operation indicated the similar ability to produce methane in the three systems, with a methane yield of 0.44 L/g VS_a_d_d_e_d. The pH drop to less than 4.0 in the first stage of two-stage system without recycle resulted in poor hydrolysis, and methane or hydrogen was not produced in this stage. Alkalinity supplement from the second stage of two-stage system with recycle improved pH in the first stage to 5.4. Consequently, 35.3% of the particulate COD in the influent was reduced in the first stage of two-stage system with recycle according to a COD mass balance, and hydrogen was produced with a percentage of 31.7%, accordingly. Similar solids and organic matter were removed in the single-stage system and two-stage system without recycle. More lipid degradation and the conversion of long-chain fatty acids were achieved in the single-stage system. Recycling was proved to be effective in promoting the conversion of unsaturated long-chain fatty acids into saturated fatty acids in the two-stage system.

  19. (Pittsburgh Energy Technology Center): Quarterly technical progress report for the period ending June 30, 1987. [Advanced Coal Research and Technology Development Programs

    Energy Technology Data Exchange (ETDEWEB)

    None

    1988-02-01

    Research programs on coal and coal liquefaction are presented. Topics discussed are: coal science, combustion, kinetics, surface science; advanced technology projects in liquefaction; two stage liquefaction and direct liquefaction; catalysts of liquefaction; Fischer-Tropsch synthesis and thermodynamics; alternative fuels utilization; coal preparation; biodegradation; advanced combustion technology; flue gas cleanup; environmental coordination, and technology transfer. Individual projects are processed separately for the data base. (CBS)

  20. Shear-wave velocity-based probabilistic and deterministic assessment of seismic soil liquefaction potential

    Science.gov (United States)

    Kayen, R.; Moss, R.E.S.; Thompson, E.M.; Seed, R.B.; Cetin, K.O.; Der Kiureghian, A.; Tanaka, Y.; Tokimatsu, K.

    2013-01-01

    Shear-wave velocity (Vs) offers a means to determine the seismic resistance of soil to liquefaction by a fundamental soil property. This paper presents the results of an 11-year international project to gather new Vs site data and develop probabilistic correlations for seismic soil liquefaction occurrence. Toward that objective, shear-wave velocity test sites were identified, and measurements made for 301 new liquefaction field case histories in China, Japan, Taiwan, Greece, and the United States over a decade. The majority of these new case histories reoccupy those previously investigated by penetration testing. These new data are combined with previously published case histories to build a global catalog of 422 case histories of Vs liquefaction performance. Bayesian regression and structural reliability methods facilitate a probabilistic treatment of the Vs catalog for performance-based engineering applications. Where possible, uncertainties of the variables comprising both the seismic demand and the soil capacity were estimated and included in the analysis, resulting in greatly reduced overall model uncertainty relative to previous studies. The presented data set and probabilistic analysis also help resolve the ancillary issues of adjustment for soil fines content and magnitude scaling factors.

  1. Accuracy of the One-Stage and Two-Stage Impression Techniques: A Comparative Analysis

    Directory of Open Access Journals (Sweden)

    Ladan Jamshidy

    2016-01-01

    Full Text Available Introduction. One of the main steps of impression is the selection and preparation of an appropriate tray. Hence, the present study aimed to analyze and compare the accuracy of one- and two-stage impression techniques. Materials and Methods. A resin laboratory-made model, as the first molar, was prepared by standard method for full crowns with processed preparation finish line of 1 mm depth and convergence angle of 3-4°. Impression was made 20 times with one-stage technique and 20 times with two-stage technique using an appropriate tray. To measure the marginal gap, the distance between the restoration margin and preparation finish line of plaster dies was vertically determined in mid mesial, distal, buccal, and lingual (MDBL regions by a stereomicroscope using a standard method. Results. The results of independent test showed that the mean value of the marginal gap obtained by one-stage impression technique was higher than that of two-stage impression technique. Further, there was no significant difference between one- and two-stage impression techniques in mid buccal region, but a significant difference was reported between the two impression techniques in MDL regions and in general. Conclusion. The findings of the present study indicated higher accuracy for two-stage impression technique than for the one-stage impression technique.

  2. Studies on characteristics of fluid dynamics in the coal liquefaction reactor; Sekitan ekika hanno tonai no ryudo tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Sakawaki, K.; Nogami, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan); Mochizuki, M.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Tachikawa, N.; Moki, T.; Ishikawa, I. [Japan Atomic Energy Research Institute, Tokyo (Japan)

    1996-10-28

    To design the coal liquefaction reactor of large scale plant in future, it is important to understand characteristics of fluid dynamics within the coal liquefaction reactor. In this study, to measure the fluid dynamics of liquid phase within the coal liquefaction reactor operated under high temperature and high pressure coal liquefaction condition, neutron attenuating tracer (NAT) technique, one of the tracer test methods, was applied using 1 t/d coal treating PSU. The residence time of liquid phase within the reactor can be measured by utilizing property of neutron of being absorbed by materials. The tracer was injected at the inlets of first and third reactors, and the neutron was counted at each outlet. The concentration of tracer was derived from the discrete value, to determine the residence time distribution of liquid phase. The mean residence time of liquid phase in the single first reactor and in the total three reactors were prolonged under the severe operation conditions of liquefaction. The more severe the liquefaction operation condition was, the more active the mixing of liquid phase was in the first reactor. It was found that the progress of reaction was accelerated. 2 refs., 5 figs., 1 tab.

  3. St. Louis area earthquake hazards mapping project; seismic and liquefaction hazard maps

    Science.gov (United States)

    Cramer, Chris H.; Bauer, Robert A.; Chung, Jae-won; Rogers, David; Pierce, Larry; Voigt, Vicki; Mitchell, Brad; Gaunt, David; Williams, Robert; Hoffman, David; Hempen, Gregory L.; Steckel, Phyllis; Boyd, Oliver; Watkins, Connor M.; Tucker, Kathleen; McCallister, Natasha

    2016-01-01

    We present probabilistic and deterministic seismic and liquefaction hazard maps for the densely populated St. Louis metropolitan area that account for the expected effects of surficial geology on earthquake ground shaking. Hazard calculations were based on a map grid of 0.005°, or about every 500 m, and are thus higher in resolution than any earlier studies. To estimate ground motions at the surface of the model (e.g., site amplification), we used a new detailed near‐surface shear‐wave velocity model in a 1D equivalent‐linear response analysis. When compared with the 2014 U.S. Geological Survey (USGS) National Seismic Hazard Model, which uses a uniform firm‐rock‐site condition, the new probabilistic seismic‐hazard estimates document much more variability. Hazard levels for upland sites (consisting of bedrock and weathered bedrock overlain by loess‐covered till and drift deposits), show up to twice the ground‐motion values for peak ground acceleration (PGA), and similar ground‐motion values for 1.0 s spectral acceleration (SA). Probabilistic ground‐motion levels for lowland alluvial floodplain sites (generally the 20–40‐m‐thick modern Mississippi and Missouri River floodplain deposits overlying bedrock) exhibit up to twice the ground‐motion levels for PGA, and up to three times the ground‐motion levels for 1.0 s SA. Liquefaction probability curves were developed from available standard penetration test data assuming typical lowland and upland water table levels. A simplified liquefaction hazard map was created from the 5%‐in‐50‐year probabilistic ground‐shaking model. The liquefaction hazard ranges from low (60% of area expected to liquefy) in the lowlands. Because many transportation routes, power and gas transmission lines, and population centers exist in or on the highly susceptible lowland alluvium, these areas in the St. Louis region are at significant potential risk from seismically induced liquefaction and associated

  4. Two-Stage Centrifugal Fan

    Science.gov (United States)

    Converse, David

    2011-01-01

    Fan designs are often constrained by envelope, rotational speed, weight, and power. Aerodynamic performance and motor electrical performance are heavily influenced by rotational speed. The fan used in this work is at a practical limit for rotational speed due to motor performance characteristics, and there is no more space available in the packaging for a larger fan. The pressure rise requirements keep growing. The way to ordinarily accommodate a higher DP is to spin faster or grow the fan rotor diameter. The invention is to put two radially oriented stages on a single disk. Flow enters the first stage from the center; energy is imparted to the flow in the first stage blades, the flow is redirected some amount opposite to the direction of rotation in the fixed stators, and more energy is imparted to the flow in the second- stage blades. Without increasing either rotational speed or disk diameter, it is believed that as much as 50 percent more DP can be achieved with this design than with an ordinary, single-stage centrifugal design. This invention is useful primarily for fans having relatively low flow rates with relatively high pressure rise requirements.

  5. Outline of research achievement of fiscal 1983. Development of coal liquefaction technologies; Sekitan ekika gijutsu kaihatsu. 1983 nendo kenkyu seika no gaiyo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-07-01

    Reported are the results of (1) the development of bituminous coal liquefaction technology, (2) development of brown coal liquefaction technology, (3) experimental fabrication and development of plant equipment and materials therefor, and (4) a survey on coal type selection. The goals of the development are mentioned below. Under Item (1), an optimum liquefaction process and a solid/liquid separation process are to be defined, the effect of iron-based catalysts upon liquefaction reaction is to be elucidated, a technology for constructing a direct hydroliquefaction unit is to be established, and a plant using such a unit is to be developed. Under Item (2), an optimum liquefaction technology is to be established, high in economic efficiency and reliability, by subjecting Australia's Victoria brown coal to the direct liquefaction process. In particular, a new brown coal liquefaction technology is to be established, which will be an organic combination of a novel, raw brown coal slurry dehydration technology, a solvent deashing technology, and the secondary hydrogenation technology, all centering on the basic technology of primary hydrogenation. Under Item (3), reactor materials, accessory materials, slurry pumps, etc., are to be experimentally manufactured and developed further. Under Item (4), data are to be collected on coal resources, coal quality, liquefaction characteristics, etc., during the process of technology development for liquefaction, etc. Furthermore, methods are to be established for the effective utilization of liquefaction products and for their optimum refining. (NEDO)

  6. Post-cyclic behavior of low plasticity silt under full and limited liquefaction using triaxial compression testing.

    Science.gov (United States)

    2010-02-01

    During an earthquake, liquefaction does not happen all the time. It depends on the duration and magnitude of the earthquake and the properties (with relationship to resistance of liquefaction) of the low plasticity silt. Under low duration or magnitu...

  7. Indirect coal liquefaction - the first commercial CTL project in the USA

    Energy Technology Data Exchange (ETDEWEB)

    Radtke, K.; Battensby, D.; Marsico, C.; Hooper, M.; Mather, C. [Uhde GmbH (Germany)

    2006-07-01

    The polygeneration of fuels, chemical and power offers an innovative and economically advantageous way to utilise disadvantaged fuels, such as lignite, waste coal and petroleum coke, in a coal-to-liquids (CTL) plant by means of integration of three main process blocks: gasification island to convert coal into clean synthesis gas; Fischer-Tropsch synthesis to convert synthesis gas into clean liquid fuels and chemicals; and combustion of synthesis gas to produce electric power and steam. This paper describes the process and technology side of this indirect coal liquefaction project with key plant data that has been elaborated for a commercial scale CTL project, which is expected to be the first CTL plant in the USA. The plant will use the Shell Coal Gasification process. 6 figs.

  8. Stuart oil shale project stage two: executive summary: draft environmental impact statement

    International Nuclear Information System (INIS)

    1999-09-01

    The project is an oil shale open pit mine and processing operation that is currently being commissioned 15 km north of Gladstone, Queensland, Australia, and is owned as a joint venture by Southern Pacific Petroleum N.L., Central Pacific Minerals N.L, and Suncor Energy Inc., a leading Canadian company that is an integrated energy company. The results of a comprehensive investigation are included of the potential environmental impacts of the project, and which are described in the Draft Environmental Impact Statement (EIS). In stage two, there is included the existing mine expansion as well as the construction of an additional process plant based around a larger commercial scale ATP oil shale processing plant. The new stage two operation will be developed next to and integral with services and infrastructure provided for stage one. Described are: the assessment process, regulatory framework and the project area, the needs for an alternative to the project, the proposal itself, the existing natural, social and economic impacts, and the environmental impacts as well as plans for their mitigation. In appendices there are included a draft environmental management overview strategy and an environmental management plan. The elements covered in the report by section are: background, need for the project, the proponent, legislation and approvals, project description, environmental issues and impact management

  9. Liquefaction of torrefied wood using microwave irradiation

    Science.gov (United States)

    Mengchao Zhou; Thomas Eberhardt; Pingping Xin; Chung-Yun Hse; Hui Pan

    2016-01-01

    Torrefaction is an effective pretreatment method to improve the uniformity and quality of lignocellulosic biomass before further thermal processing (e.g., gasification, combustion). The objective of this study was to determine the impacts of torrefaction as a pretreatment before liquefaction. Wood chips were torrefied for 2 h at three different temperatures (230, 260,...

  10. Enhanced coproduction of hydrogen and methane from cornstalks by a three-stage anaerobic fermentation process integrated with alkaline hydrolysis.

    Science.gov (United States)

    Cheng, Xi-Yu; Liu, Chun-Zhao

    2012-01-01

    A three-stage anaerobic fermentation process including H(2) fermentation I, H(2) fermentation II, methane fermentation was developed for the coproduction of hydrogen and methane from cornstalks. Hydrogen production from cornstalks using direct microbial conversion by Clostridium thermocellum 7072 was markedly enhanced in the two-stage thermophilic hydrogen fermentation process integrated with alkaline treatment. The highest total hydrogen yield from cornstalks in the two-stage fermentation process reached 74.4 mL/g-cornstalk. The hydrogen fermentation effluents and alkaline hydrolyzate were further used for methane fermentation by anaerobic granular sludge, and the total methane yield reached 205.8 mL/g-cornstalk. The total energy recovery in the three-stage anaerobic fermentation process integrated with alkaline hydrolysis reached 70.0%. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Finite Element Modelling of Seismic Liquefaction in Soils

    NARCIS (Netherlands)

    Galavi, V.; Petalas, A.; Brinkgreve, R.B.J.

    2013-01-01

    Numerical aspects of seismic liquefaction in soils as implemented in the finite element code, PLAXIS, is described in this paper. After description of finite element equations of dynamic problems, three practical dynamic boundary conditions, namely viscous boundary tractions, tied degrees of freedom

  12. Probabilistic and Scenario Seismic and Liquefaction Hazard Analysis of the Mississippi Embayment Incorporating Nonlinear Site Effects

    Science.gov (United States)

    Cramer, C. H.; Dhar, M. S.

    2017-12-01

    The influence of deep sediment deposits of the Mississippi Embayment (ME) on the propagation of seismic waves is poorly understood and remains a major source of uncertainty for site response analysis. Many researchers have studied the effects of these deposits on seismic hazard of the area using available information at the time. In this study, we have used updated and newly available resources for seismic and liquefaction hazard analyses of the ME. We have developed an improved 3D geological model. Additionally, we used surface geological maps from Cupples and Van Arsdale (2013) to prepare liquefaction hazard maps. Both equivalent linear and nonlinear site response codes were used to develop site amplification distributions for use in generating hazard maps. The site amplification distributions are created using the Monte Carlo approach of Cramer et al. (2004, 2006) on a 0.1-degree grid. The 2014 National Seismic Hazard model and attenuation relations (Petersen et al., 2014) are used to prepare seismic hazard maps. Then liquefaction hazard maps are generated using liquefaction probability curves from Holzer (2011) and Cramer et al. (2015). Equivalent linear response (w/ increased precision, restricted nonlinear behavior with depth) shows similar hazard for the ME compared to nonlinear analysis (w/o pore pressure) results. At short periods nonlinear deamplification dominates the hazard, but at long periods resonance amplification dominates. The liquefaction hazard tends to be high in Holocene and late Pleistocene lowland sediments, even with lowered ground water levels, and low in Pleistocene loess of the uplands. Considering pore pressure effects in nonlinear site response analysis at a test site on the lowlands shows amplification of ground motion at short periods. PGA estimates from ME liquefaction and MMI observations are in the 0.25 to 0.4 g range. Our estimated M7.5 PGA hazard within 10 km of the fault can exceed this. Ground motion observations from

  13. Coal liquefaction still a dream

    Energy Technology Data Exchange (ETDEWEB)

    Overberg, H

    1982-03-19

    Liquefaction of coal is not profitable in West Germany and will not be so far some time to coal. This is true for West German and imported coal. The result may be improved but not changed by combined conversion of coal and top residues of distilleries. These are the main statements of a study carried out by Messrs. Veba Oel AG, Gelsenkirchen, on behalf of the Federal Minister for Research and Technology. The results of the study are presented in 20 volumes.

  14. Profile fitting and the two-stage method in neutron powder diffractometry for structure and texture analysis

    International Nuclear Information System (INIS)

    Jansen, E.; Schaefer, W.; Will, G.; Kernforschungsanlage Juelich G.m.b.H.

    1988-01-01

    An outline and an application of the two-stage method in neutron powder diffractometry are presented. Stage (1): Individual reflection data like position, half-width and integrated intensity are analysed by profile fitting. The profile analysis is based on an experimentally determined instrument function and can be applied without prior knowledge of a structural model. A mathematical procedure is described which results in a variance-covariance matrix containing standard deviations and correlations of the refined reflection parameters. Stage (2): The individual reflection data derived from the profile fitting procedure can be used for appropriate purposes either in structure determination or in texture and strain or stress analysis. The integrated intensities are used in the non-diagonal weighted least-squares routine POWLS for structure refinement. The weight matrix is given by the inverted variance-covariance matrix of stage (1). This procedure is the basis for reliable and real Bragg R values and for a realistic estimation of standard deviations of structural parameters. In the case of texture analysis the integrated intensities are compiled into pole figures representing the intensity distribution for all sample orientations of individual hkl. Various examples for the wide application of the two-stage method in structure and texture analysis are given: Structure refinement of a standard quartz specimen, magnetic ordering in the system Tb x Y 1-x Ag, preferred orientation effects in deformed marble and texture investigations of a triclinic plagioclase. (orig.)

  15. SUMMARY REPORT OF THE DOE DIRECT LIQUEFACTION PROCESS DEVELOPMENT CAMPAIGN OF THE LATE TWENTIETH CENTURY; FINAL

    International Nuclear Information System (INIS)

    F.P. Burke; S.D. Brandes; D.C. McCoy; R.A. Winschel; D. Gray; G. Tomlinson

    2001-01-01

    Following the petroleum price and supply disruptions of 1973, the U.S. government began a substantial program to fund the development of alternative fuels. Direct coal liquefaction was one of the potential routes to alternative fuels. The direct coal liquefaction program was funded at substantial levels through 1982, and at much lower levels thereafter. Those processes that were of most interest during this period were designed to produce primarily distillate fuels. By 1999, U.S. government funding for the development of direct coal liquefaction ended. Now that the end of this campaign has arrived, it is appropriate to summarize the process learnings derived from it. This report is a summary of the process learnings derived from the DOE direct coal liquefaction process development campaign of the late twentieth century. The report concentrates on those process development programs that were designed to produce primarily distillate fuels and were largely funded by DOE and its predecessors in response to the petroleum supply and price disruptions of the 1970s. The report is structured as chapters written by different authors on most of the major individual DOE-funded process development programs. The focus of the report is process learnings, as opposed to, say, fundamental coal liquefaction science or equipment design. As detailed in the overview (Chapter 2), DOE's direct coal liquefaction campaign made substantial progress in improving the process yields and the quality of the distillate product. Much of the progress was made after termination by 1983 of the major demonstration programs of the ''first generation'' (SRC-II, H-Coal, EDS) processes

  16. Determination of Liquefaction Potential using Artificial Neural Networks

    DEFF Research Database (Denmark)

    Farrokhzad, F; Choobbasti, A.J; Barari, Amin

    2011-01-01

    The authors propose an alternative general regression model based on neural networks, which enables analysis of summary data obtained by liquefaction analysis according to usual methods. For that purpose, the data from some thirty boreholes made during field investigations in Babol, in the Iranian...

  17. Model of unplanned smoking initiation of children and adolescents: an integrated stage model of smoking behavior.

    Science.gov (United States)

    Kremers, S P J; Mudde, A N; De Vries, H

    2004-05-01

    Two lines of psychological research have attempted to spell out the stages of adolescent smoking initiation. The first has focused on behavioral stages of smoking initiation, while the second line emphasized motivational stages. A large international sample of European adolescents (N = 10,170, mean age = 13.3 years) was followed longitudinally. Self-reported motivational and behavioral stages of smoking initiation were integrated, leading to the development of the Model of Unplanned Smoking Initiation of Children and Adolescents (MUSICA). The MUSICA postulates that youngsters experiment with smoking while they are in an unmotivated state as regards their plans for smoking regularly in the future. More than 95% of the total population resided in one of the seven stages distinguished by MUSICA. The probability of starting to smoke regularly during the 12 months follow-up period increased with advanced stage assignment at baseline. Unique social cognitive predictors of stage progression from the various stages were identified, but effect sizes of predictors of transitions were small. The integration of motivational and behavioral dimensions improves our understanding of the process of smoking initiation. In contrast to current theories of smoking initiation, adolescent uptake of smoking behavior was found to be an unplanned action.

  18. Assessment of materials selection and performance for direct-coal- liquefaction plants in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, A.R.; Judkins, R.R.; Keiser, J.R.

    1996-09-01

    Several direct coal liquefaction processes have been demonstrated at the pilot plant level in the United States. Presently only one plant remains operational, namely, the Hydrocarbon Technologies, Inc., 4.0- ton-per-day process development unit in Lawrenceville, New Jersey. The period from 1974 to 1982 saw the greatest amount of development of direct coal liquefaction in the United States with four major pilot plants being devoted to variants of this technology. The plants included the SRC-I plant at Wilsonville, Alabama, which operated from 1974 to 1992; the SRC-I/II plant at Fort Lewis, Washington, which operated from 1974 to 1981; the H-Coal plant at Catlettsburg, Kentucky, which operated from 1980 to 1982; and the Exxon Coal Liquefaction Pilot Plant at Baytown, Texas, which operated from 1980 to 1982. Oak Ridge National Laboratory scientists and engineers were actively involved in many phases and technical disciplines at all four of these plants, especially in materials testing, evaluation, and failure analyses. In addition, ORNL materials scientists and engineers conducted reviews of the demonstration and commercial plant designs for materials selections. The ORNL staff members worked closely with materials engineers at the pilot plants in identifying causes of materials degradation and failures, and in identifying solutions to these problems. This report provides a comprehensive summary of those materials activities. Materials performance data from laboratory and coal liquefaction pilot plant tests, failure analyses, and analyses of components after use in pilot plants were reviewed and assessed to determine the extent and causes of materials degradation in direct coal liquefaction process environments. Reviews of demonstration and commercial plant design documents for materials selections were conducted. These reviews and assessments are presented to capture the knowledge base on the most likely materials of construction for direct coal liquefaction plants.

  19. Japan`s New Sunshine Project. 1996 Annual Summary of Coal Liquefaction and Gasification; 1996 nendo new sunshine keikaku seika hokokusho gaiyoshu. Sekitan no ekika gasuka

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    In reference to the results of the research and development under the fiscal 1996 New Sunshine Project, a report was summed up on coal liquefaction and coal gasification. As to the R and D of coal liquefaction technology, researches were conducted on liquefaction characteristics and engineering properties by coal kind, catalysts for coal liquefaction, liquefaction reaction of coal and reformation utilization of the liquefied products, liquefaction reaction mechanism and coking mechanism, solubility of coal in solvent and catalytic reaction mechanism, solvent reaction mechanism by hydrogen donor solvent, etc. Concerning the R and D of coal gasification technology, made were the basic study of eco-technology adaptable gasification technology and the study of coal gasification enhancing technology. Further, as to the development of bituminous coal liquefaction technology, carried out were the study in pilot plants and the support study of pilot plants. Additionally, R and D were done of the basic technology of coal liquefaction such as upgrading technology and environmentally acceptable coal liquefaction technology, and of coal hydrogasification technology. 3 refs., 81 figs., 25 tabs.

  20. Influence of saturation degree and role of suction in unsaturated soils behaviour: application to liquefaction

    Directory of Open Access Journals (Sweden)

    Vernay Mathilde

    2016-01-01

    Full Text Available The effect of the pore fluid compressibility on liquefaction has been studied by various authors. But few papers have been published about the role of suction in cyclic behavior of unsaturated soils. Most of these works use Skempton coefficient B as a reference in terms of saturation degree to analyze their results. The use of B in experimental conditions is convenient, but is not accurate when studying liquefaction behavior, since effects of suction are neglected. In this paper, the influence of saturation degree on mechanical behavior of a soil under dynamic loads is studied. Cyclic undrained triaxial tests were performed on sand samples, under various levels of saturation. Soil-water characteristic curve was used, in order to study influence of suction. The first results confirm that when the degree of saturation decreases, the resistance increases. Initial positive suction tends to stiffen the soil. It also appears that the presence of air delays the occurrence of liquefaction, but doesn’t prevent it. Indeed, liquefaction is observed, whether the soil is saturated or not.

  1. Coal liquefaction with preasphaltene recycle

    Science.gov (United States)

    Weimer, Robert F.; Miller, Robert N.

    1986-01-01

    A coal liquefaction system is disclosed with a novel preasphaltene recycle from a supercritical extraction unit to the slurry mix tank wherein the recycle stream contains at least 90% preasphaltenes (benzene insoluble, pyridine soluble organics) with other residual materials such as unconverted coal and ash. This subject process results in the production of asphaltene materials which can be subjected to hydrotreating to acquire a substitute for No. 6 fuel oil. The preasphaltene-predominant recycle reduces the hydrogen consumption for a process where asphaltene material is being sought.

  2. Survival of Legionella in earthquake-induced soil disturbance (liquefaction) in residential areas, Christchurch, New Zealand: implications for disease.

    Science.gov (United States)

    Graham, Frances F; Harte, David Jg

    2017-05-12

    To investigate a possible link between liquefaction dust exposure and the noticeable increase in legionellosis cases in response to major earthquakes in 2010 and 2011 that resulted in widespread soil disturbance (liquefaction) in parts of Christchurch, New Zealand. We culture tested liquefaction-affected soil for Legionella spp. in the six months following the first earthquake in 2010. Thirty silt samples were collected randomly from locations within Christchurch's metropolitan area that were affected by liquefaction. The samples were tested to determine the presence of Legionella using qualitative and quantitative methods. Liquefaction-affected soil samples from three sites were further subjected to particle size distribution analysis and determination of major oxides. A controlled field study was established using six silt samples and one control (commercial compost), seeded with a wild-type strain of Legionella bozemanae serogroup (sg) 1 and persistence monitored over a 60-day period by culturing for the presence of Legionella. Dry matter determinations were undertaken so that total Legionella could be calculated on a dry weight basis. Legionella bacteria were undetectable after day one in the silt samples. However, L. bozemanae sg1 was detected in the control sample for the entire study period. This study showed that the liquefaction-affected soil could not contribute directly to the observed increase in legionellosis cases after the earthquakes due to its inability to support growth and survival of the Legionella bacteria.

  3. Low-Cost Methane Liquefaction Plant and Vehicle Refueling Station

    International Nuclear Information System (INIS)

    Wilding, B.; Bramwell, D.

    1999-01-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) is currently negotiating a collaborative effort with Pacific Gas and Electric (PG and E) that will advance the use of liquefied natural gas (LNG) as a vehicle fuel. We plan to develop and demonstrate a small-scale methane liquefaction plant (production of 5,000 to 10,000 gallons per day) and a low-cost ($150,000) LNG refueling station to supply fuel to LNG-powered transit buses and other heavy-duty vehicles. INEEL will perform the research and development work. PG and E will deploy the new facilities commercially in two demonstration projects, one in northern California, and one in southern California

  4. Fiscal 1997 achievement report. Coal liquefaction technology development - Bituminous coal liquefaction technology development - Study for supporting pilot plant - Study using 1t/d PSU (Study of operation using PSU); 1997 nendo seika hokokusho. Sekitan ekika gijutsu kaihatsu - Rekiseitan ekika gijutsu no kaihatsu - Pilot plant no shien kenkyu - 1t/d process support unit (PSU) ni yoru kenkyu (PSU ni yoru unten kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The operation of a 1t/d PSU (process support unit) was studied for the NEDOL coal liquefaction process. In the modification of facilities, equipment and devices were procured for the product oil reforming facilities and their installation was partly accomplished. In the coal injection operation, a 60-day slurry operation was conducted, using coal types of the upper limit and lower limit qualities, for expanding the scope of coal types applicable to the NEDOL process and for exploring optimum conditions, and another operation of 37 days was conducted using Chinese coal and Chinese-prepared liquefaction catalysts, and the two operations were studied for difference in yields and in operationality. Characteristics of the liquefaction reactors were investigated and basic studies were made relative to the physical property of the yielded coal oil. In the operation for maintenance, the 1st liquefaction reactor was singly operated for an 8-day slurry operation, which was to check the progress of liquefaction in a 1-reactor setup. Concerning the reforming of the product oil, the hydrogenation reactors were checked for their response to temperature control. Moreover, hydrogenation solvents were produced for the PSU and for China. (NEDO)

  5. Characteristics of process oils from HTI coal/plastics co-liquefaction runs

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, G.A.; Brandes, S.D.; Winschel, R.A. [and others

    1995-12-31

    The objective of this project is to provide timely analytical support to DOE`s liquefaction development effort. Specific objectives of the work reported here are presented. During a few operating periods of Run POC-2, HTI co-liquefied mixed plastics with coal, and tire rubber with coal. Although steady-state operation was not achieved during these brief tests periods, the results indicated that a liquefaction plant could operate with these waste materials as feedstocks. CONSOL analyzed 65 process stream samples from coal-only and coal/waste portions of the run. Some results obtained from characterization of samples from Run POC-2 coal/plastics operation are presented.

  6. Initial Earthquake Centrifuge Model Experiments for the Study of Liquefaction

    National Research Council Canada - National Science Library

    Steedman, R

    1998-01-01

    .... These are intended to gather data suitable for the development of improved design approaches for the prediction of liquefaction under earthquake loading using the new centrifuge facility at the WES...

  7. An Advanced Wet Expansion Turbine for Hydrogen Liquefaction, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is responsive to NASA SBIR Topic X10.01, specifically, the need for efficient small- to medium-scale hydrogen liquefaction technologies including...

  8. Nitrogen expander cycles for large capacity liquefaction of natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Ho-Myung; Park, Jae Hoon; Gwak, Kyung Hyun [Hong Ik University, Department of Mechanical Engineering, Seoul, 121-791 (Korea, Republic of); Choe, Kun Hyung [Korea Gas Corporation, Incheon, 406-130 (Korea, Republic of)

    2014-01-29

    Thermodynamic study is performed on nitrogen expander cycles for large capacity liquefaction of natural gas. In order to substantially increase the capacity, a Brayton refrigeration cycle with nitrogen expander was recently added to the cold end of the reputable propane pre-cooled mixed-refrigerant (C3-MR) process. Similar modifications with a nitrogen expander cycle are extensively investigated on a variety of cycle configurations. The existing and modified cycles are simulated with commercial process software (Aspen HYSYS) based on selected specifications. The results are compared in terms of thermodynamic efficiency, liquefaction capacity, and estimated size of heat exchangers. The combination of C3-MR with partial regeneration and pre-cooling of nitrogen expander cycle is recommended to have a great potential for high efficiency and large capacity.

  9. Nitrogen expander cycles for large capacity liquefaction of natural gas

    Science.gov (United States)

    Chang, Ho-Myung; Park, Jae Hoon; Gwak, Kyung Hyun; Choe, Kun Hyung

    2014-01-01

    Thermodynamic study is performed on nitrogen expander cycles for large capacity liquefaction of natural gas. In order to substantially increase the capacity, a Brayton refrigeration cycle with nitrogen expander was recently added to the cold end of the reputable propane pre-cooled mixed-refrigerant (C3-MR) process. Similar modifications with a nitrogen expander cycle are extensively investigated on a variety of cycle configurations. The existing and modified cycles are simulated with commercial process software (Aspen HYSYS) based on selected specifications. The results are compared in terms of thermodynamic efficiency, liquefaction capacity, and estimated size of heat exchangers. The combination of C3-MR with partial regeneration and pre-cooling of nitrogen expander cycle is recommended to have a great potential for high efficiency and large capacity.

  10. Nitrogen expander cycles for large capacity liquefaction of natural gas

    International Nuclear Information System (INIS)

    Chang, Ho-Myung; Park, Jae Hoon; Gwak, Kyung Hyun; Choe, Kun Hyung

    2014-01-01

    Thermodynamic study is performed on nitrogen expander cycles for large capacity liquefaction of natural gas. In order to substantially increase the capacity, a Brayton refrigeration cycle with nitrogen expander was recently added to the cold end of the reputable propane pre-cooled mixed-refrigerant (C3-MR) process. Similar modifications with a nitrogen expander cycle are extensively investigated on a variety of cycle configurations. The existing and modified cycles are simulated with commercial process software (Aspen HYSYS) based on selected specifications. The results are compared in terms of thermodynamic efficiency, liquefaction capacity, and estimated size of heat exchangers. The combination of C3-MR with partial regeneration and pre-cooling of nitrogen expander cycle is recommended to have a great potential for high efficiency and large capacity

  11. Determination of soil liquefaction characteristics by large-scale laboratory tests

    International Nuclear Information System (INIS)

    1975-05-01

    The testing program described in this report was carried out to study the liquefaction behavior of a clean, uniform, medium sand. Horizontal beds of this sand, 42 inches by 90 inches by 4 inches were prepared by pluviation with a special sand spreader, saturated, and tested in a shaking table system designed for this program, which applied a horizontal cyclic shear stress to the specimens. Specimen size was selected to reduce boundary effects as much as possible. Values of pore pressures and shear strains developed during the tests are presented for sand specimens at relative densities of 54, 68, 82, and 90 percent, and the results interpreted to determine the values of the stress ratio causing liquefaction at the various relative densities

  12. Two-stage free electron laser research

    Science.gov (United States)

    Segall, S. B.

    1984-10-01

    KMS Fusion, Inc. began studying the feasibility of two-stage free electron lasers for the Office of Naval Research in June, 1980. At that time, the two-stage FEL was only a concept that had been proposed by Luis Elias. The range of parameters over which such a laser could be successfully operated, attainable power output, and constraints on laser operation were not known. The primary reason for supporting this research at that time was that it had the potential for producing short-wavelength radiation using a relatively low voltage electron beam. One advantage of a low-voltage two-stage FEL would be that shielding requirements would be greatly reduced compared with single-stage short-wavelength FEL's. If the electron energy were kept below about 10 MeV, X-rays, generated by electrons striking the beam line wall, would not excite neutron resonance in atomic nuclei. These resonances cause the emission of neutrons with subsequent induced radioactivity. Therefore, above about 10 MeV, a meter or more of concrete shielding is required for the system, whereas below 10 MeV, a few millimeters of lead would be adequate.

  13. Two-Stage Battery Energy Storage System (BESS in AC Microgrids with Balanced State-of-Charge and Guaranteed Small-Signal Stability

    Directory of Open Access Journals (Sweden)

    Bing Xie

    2018-02-01

    Full Text Available In this paper, a two-stage battery energy storage system (BESS is implemented to enhance the operation condition of conventional battery storage systems in a microgrid. Particularly, the designed BESS is composed of two stages, i.e., Stage I: integration of dispersed energy storage units (ESUs using parallel DC/DC converters, and Stage II: aggregated ESUs in grid-connected operation. Different from a conventional BESS consisting of a battery management system (BMS and power conditioning system (PCS, the developed two-stage architecture enables additional operation and control flexibility in balancing the state-of-charge (SoC of each ESU and ensures the guaranteed small-signal stability, especially in extremely weak grid conditions. The above benefits are achieved by separating the control functions between the two stages. In Stage I, a localized power sharing scheme based on the SoC of each particular ESU is developed to manage the SoC and avoid over-charge or over-discharge issues; on the other hand, in Stage II, an additional virtual impedance loop is implemented in the grid-interactive DC/AC inverters to enhance the stability margin with multiple parallel-connected inverters integrating at the point of common coupling (PCC simultaneously. A simulation model based on MATLAB/Simulink is established, and simulation results verify the effectiveness of the proposed BESS architecture and the corresponding control diagram.

  14. Optimizing the conditions for the microwave-assisted direct liquefaction of Ulva prolifera for bio-oil production using response surface methodology

    International Nuclear Information System (INIS)

    Liu, Junhai; Zhuang, Yingbin; Li, Yan; Chen, Limei; Guo, Jingxue; Li, Demao; Ye, Naihao

    2013-01-01

    Microwave-assisted direct liquefaction (MADL) of Ulva prolifera was performed in ethylene glycol (EG) using sulfuric acid (H 2 SO 4 ) as a catalyst. Response Surface Methodology (RSM) based on central composite rotatable design (CCRD) was employed to optimize the conditions of three independent variables (catalyst content, solvent-to-feedstock ratio and temperature) for the liquefaction yield. And the bio-oil was analyzed by elementary analysis, Fourier transform infrared spectroscopic analysis (FT-IR) and gas chromatography–mass spectrometry (GC–MS). The maximum liquefaction yield was 93.17%, which was obtained under a microwave power of 600 W for 30 min at 165 °C with a solvent-to-feedstock ratio of 18.87:1 and 4.93% sulfuric acid. The bio-oil was mainly composed of phthalic acid esters, alkenes and a fatty acid methyl ester with a long chain from C 16 to C 20 . - Highlights: • Ulva prolifera was converted to bio-oil through microwave-assisted direct liquefaction. • Response surface methodology was used to optimize the liquefaction technology. • A maximum liquefaction rate of 93.17 wt% bio-oil was obtained. • The bio-oil was composed of carboxylic acids and esters

  15. Subcritical hydrothermal liquefaction of barley straw in fresh water and recycled aqueous phase

    DEFF Research Database (Denmark)

    Zhu, Zhe; Toor, Saqib; Rosendahl, Lasse

    2014-01-01

    This project focuses on the investigation of addition of aqueous phase in the production of biofuel from biomass through hydrothermal liquefaction (HTL) technology. Hydrothermal liquefaction is a wet thermal conversion process, which can convert all kinds of biomass to fuels. In this study, barley...... straw was first liquefied in fresh distilled water with the presence of K2CO3 catalyst at 300 C as the reference run. Afterwards, the aqueous phase which is obtained from liquefaction process in the previous run was recycled and used as the reaction medium from the second to the fourth run....... With the addition of recycling aqueous phase in HTL process, it is expected that the amount of the waste water and energy consumption can be reduced. The effect of water recirculation on product yield and properties was investigated in this study. The results showed that bio-oil yield was 34.85 wt% when the barley...

  16. Catalytic hydrothermal liquefaction (HTL of biomass for bio-crude production using Ni/HZSM-5 catalysts

    Directory of Open Access Journals (Sweden)

    Shouyun Cheng

    2017-04-01

    Full Text Available Hydrothermal liquefaction (HTL is an effective method that can convert biomass into bio-crude, but direct use of bio-crude derived from biomass HTL remains a challenge due to the lower quality. In this study, bifunctional Ni/HZSM-5 catalysts and zinc hydrolysis were combined to produce upgraded bio-crude in an in-situ HTL process. The K2CO3 and HZSM-5 catalysts with different Ni loading ratios were tested. The effects of different catalysts on the yield and quality of bio-crude and gas were investigated. The results indicated that the catalysts improved bio-crude and gas yields, compared to pine sawdust liquefaction without catalyst. The catalysts reduced the contents of undesirable oxygenated compounds such as acids, ketones, phenols, alcohols and esters in bio-crude products while increased desirable hydrocarbons content. K2CO3 produced highest bio-crude yield and lowest solid residue yield among all catalysts. Compared to parent HZSM-5 catalyst, bifunctional Ni/HZSM-5 catalysts exhibited higher catalyst activity to improve quality of upgraded bio-crude due to its integration of cracking and hydrodeoxygenation reactions. 6%Ni/HZSM-5 catalyst produced the bio-crude with the highest hydrocarbons content at 11.02%. This catalyst can be a candidate for bio-crude production from biomass HTL.

  17. Geological occurrence response to trace elemental migration in coal liquefaction based on SPSS: take no. 11 coalbed in Antaibao mine for example

    Science.gov (United States)

    Xia, Xiaohong; Qin, Yong; Yang, Weifeng

    2013-03-01

    Coal liquefaction is an adoptable method to transfer the solid fossil energy into liquid oil in large scale, but the dirty material in which will migrate to different step of liquefaction. The migration rule of some trace elements is response to the react activity of macerals in coal and the geological occurrence of the element nature of itself. In this paper, from the SPSS data correlation analysis and hierarchical clustering dendrogram about the trace elements with macerals respond to coal liquefaction yield, it shows the trace elements in No.11 Antaibao coal seam originated from some of lithophile and sulphophle elements. Correlation coefficient between liquefaction yield of three organic macerals and migration of the elements in liquefaction residue indicated that the lithophile are easy to transfer to residue, while sulphophle are apt to in the liquid products. The activated macerals are response to sulphophle trace elements. The conclusion is useful to the coal blending and environmental effects on coal direct liquefaction.

  18. Isolation and characterization of cellulose nanofibers from bamboo using microwave liquefaction combined with chemical treatment and ultrasonication

    Science.gov (United States)

    Jiulong Xie; Chung Hse; Cornelis F. De Hoop; Tingxing Hu; Jinqiu Qi; Todd F. Shupe

    2016-01-01

    Cellulose nanofibers were successfully isolated from bamboo using microwave liquefaction combinedwith chemical treatment and ultrasonic nanofibrillation processes. The microwave liquefaction couldeliminate almost all the lignin in bamboo, resulting in high cellulose content residues within 7 min, andthe cellulose enriched residues could be readily purified by...

  19. Efficient Air Desulfurization Catalysts Derived from Pig Manure Liquefaction Char

    Directory of Open Access Journals (Sweden)

    Rajiv Wallace

    2017-11-01

    Full Text Available Biochar from the liquefaction of pig manure was used as a precursor of H2S desulfurization adsorbents. In its inorganic matter, it contains marked quantities of calcium, magnesium and iron, which are known as hydrogen sulfide oxidation catalysts. The char was used either as-received or mixed with 10% nanographite. The latter was added to increase both the content of the carbon phase and conductivity. ZnCl2 in two different ratios of char to an activation agent (1:1 and 1:2 was used to create the porosity in the carbon phase. The content of the later was between 18–45%. The activated samples adsorbed 144 mg/g H2S. Sulfur was the predominant product of reactive adsorption. Its deposition in the pore system and blockage of the most active pores ceased the materials’ activity. The presence of the catalytic phase was necessary but not sufficient to guarantee good performance. The developed porosity, which can store oxidation products in the resulting composite, is essential for the good performance of the desulfurization process. The surface of the composite with nanographite showed the highest catalytic activity, similar to that of the commercial Midas® carbon catalyst. The results obtained indicate that a high quality reactive adsorbent/catalyst for H2S removal can be obtained from pig manure liquefaction wastes.

  20. Maps of Quaternary Deposits and Liquefaction Susceptibility in the Central San Francisco Bay Region, California

    Science.gov (United States)

    Witter, Robert C.; Knudsen, Keith L.; Sowers, Janet M.; Wentworth, Carl M.; Koehler, Richard D.; Randolph, Carolyn E.; Brooks, Suzanna K.; Gans, Kathleen D.

    2006-01-01

    This report presents a map and database of Quaternary deposits and liquefaction susceptibility for the urban core of the San Francisco Bay region. It supercedes the equivalent area of U.S. Geological Survey Open-File Report 00-444 (Knudsen and others, 2000), which covers the larger 9-county San Francisco Bay region. The report consists of (1) a spatial database, (2) two small-scale colored maps (Quaternary deposits and liquefaction susceptibility), (3) a text describing the Quaternary map and liquefaction interpretation (part 3), and (4) a text introducing the report and describing the database (part 1). All parts of the report are digital; part 1 describes the database and digital files and how to obtain them by downloading across the internet. The nine counties surrounding San Francisco Bay straddle the San Andreas fault system, which exposes the region to serious earthquake hazard (Working Group on California Earthquake Probabilities, 1999). Much of the land adjacent to the Bay and the major rivers and streams is underlain by unconsolidated deposits that are particularly vulnerable to earthquake shaking and liquefaction of water-saturated granular sediment. This new map provides a consistent detailed treatment of the central part of the 9-county region in which much of the mapping of Open-File Report 00-444 was either at smaller (less detailed) scale or represented only preliminary revision of earlier work. Like Open-File Report 00-444, the current mapping uses geomorphic expression, pedogenic soils, inferred depositional environments, and geologic age to define and distinguish the map units. Further scrutiny of the factors controlling liquefaction susceptibility has led to some changes relative to Open-File Report 00-444: particularly the reclassification of San Francisco Bay mud (Qhbm) to have only MODERATE susceptibility and the rating of artificial fills according to the Quaternary map units inferred to underlie them (other than dams - adf). The two colored

  1. Fiscal 1989 report on the bituminous coal liquefaction section meeting; 1989 nendo rekiseitan ekika bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-03-01

    At the 1st, 2nd, and 3rd group meetings held for the fiscal year, reports are given and discussions are made about the progress of research and development. Reported and discussed in relation to the progress of the pilot plant support research are studies with the 1t/d PSU (process supporting unit) (Nippon Steel Corporation, Mitsui Coal Liquefaction Co., Ltd., and Japan Coal Oil Co., Ltd.); improvement on distillate distribution (Sumitomo Metal Industries, Ltd.); development of an optimum decalcification technique (Sumitomo Coal Mining Co., Ltd., and Sumitomo Metal Industries, Ltd.); studies of solvent hydrogenation catalysts (Sumitomo Metal Mining Co., Ltd., and Chiyoda Corp.); and studies of coal liquefaction conditions (Mitsui Engineering and Shipbuilding Co., Ltd.). In relation to studies using a bituminous coal liquefaction pilot plant, the progress of the 150t/d PP (pilot plant) effort (Japan Coal Oil, Co., Ltd.) and the outlines of pilot surveys (Japan Coal Oil Co., Ltd.) are reported and discussed, the latter covering liquefaction solvent performance optimization, slurry preheating furnaces, coal slurry properties, and so forth. (NEDO)

  2. Fiscal 1990 report on the bituminous coal liquefaction section meeting; 1990 nendo rekiseitan ekika bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-03-01

    At the 1st, 2nd, and 3rd group meetings held for the fiscal year, reports are delivered and discussions are made concerning the progress of research and development activities. Reported and discussed in relation to the pilot plant support research, etc., are studies with the 1t/d PSU (process supporting unit) (Nippon Steel Corporation, Mitsui Coal Liquefaction Co., Ltd., and Japan Coal Oil Co., Ltd.); development of an optimum coal refining technique (Sumitomo Coal Mining Co., Ltd.); development of an optimum pretreatment technique and improvement on distillate distribution (Sumitomo Metal Industries, Ltd.); studies of coal liquefaction conditions (Mitsui Engineering and Shipbuilding Co., Ltd.); and studies of solvent hydrogenation catalysts (Sumitomo Metal Mining Co., Ltd., and Chiyoda Corp.). Reported and discussed in relation to researches using a bituminous coal liquefaction pilot plant are the progress of the 150t/d PP (pilot plant) effort (Japan Coal Oil Co., Ltd.) and the outlines of pilot surveys (Japan Coal Oil Co., Ltd.), the latter covering liquefaction solvent performance optimization, slurry pre-heating furnaces, coal slurry properties, and so forth. (NEDO)

  3. A stage is a stage is a stage: a direct comparison of two scoring systems.

    Science.gov (United States)

    Dawson, Theo L

    2003-09-01

    L. Kohlberg (1969) argued that his moral stages captured a developmental sequence specific to the moral domain. To explore that contention, the author compared stage assignments obtained with the Standard Issue Scoring System (A. Colby & L. Kohlberg, 1987a, 1987b) and those obtained with a generalized content-independent stage-scoring system called the Hierarchical Complexity Scoring System (T. L. Dawson, 2002a), on 637 moral judgment interviews (participants' ages ranged from 5 to 86 years). The correlation between stage scores produced with the 2 systems was .88. Although standard issue scoring and hierarchical complexity scoring often awarded different scores up to Kohlberg's Moral Stage 2/3, from his Moral Stage 3 onward, scores awarded with the two systems predominantly agreed. The author explores the implications for developmental research.

  4. Ground Characterization Studies in Canakkale Pilot Site of LIQUEFACT Project

    Science.gov (United States)

    Ozcep, F.; Oztoprak, S.; Aysal, N.; Bozbey, I.; Tezel, O.; Ozer, C.; Sargin, S.; Bekin, E.; Almasraf, M.; Cengiz Cinku, M.; Ozdemir, K.

    2017-12-01

    The our aim is to outline the ground characterisation studies in Canakkale test site. Study is based on the EU H2020 LIQUEFACT project entitled "Liquefact: Assessment and mitigation of liquefaction potential across Europe: a holistic approach to protect structures / infrastructures for improved resilience to earthquake-induced liquefaction disasters". Objectives and extent of ground characterization for Canakkale test site includes pre-existing soil investigation studies and complementary field studies. There were several SPT and geophysical tests carried out in the study area. Within the context of the complementary tests, six (6) study areas in the test site were chosen and complementary tests were carried out in these areas. In these areas, additional boreholes were opened and SPT tests were performed. It was decided that additional CPT (CPTU and SCPT) and Marchetti Dilatometer (DMT) tests should be carried out within the scope of the complementary testing. Seismic refraction, MASW and micro tremor measurements had been carried out in pre-existing studies. Shear wave velocities obtained from MASW measurements were evaluated to the most rigorous level. These tests were downhole seismic, PS-logging, seismic refraction, 2D-ReMi, MASW, micro tremor (H/V Nakamura method), 2D resistivity and resonance acoustic profiling (RAP). RAP is a new technique which will be explained briefly in the relevant section. Dynamic soil properties had not been measured in pre-existing studies, therefore these properties were investigated within the scope of the complementary tests. Selection of specific experimental tests of the complementary campaign was based on cost-benefit considerations Within the context of complementary field studies, dynamic soil properties were measured using resonant column and cyclic direct shear tests. Several sieve analyses and Atterberg Limits tests which were documented in the pre-existing studies were evaluated. In the complementary study carried out

  5. The making of Andersen’s liquefaction chart

    OpenAIRE

    Sabaliauskas, Tomas; Ibsen, Lars Bo

    2017-01-01

    Andersen’s chart (Andersen & Berre, 1999) is a graphical method of observing cyclic soil response. It allows observing soil response to various stress amplitudes that can lead to liquefaction, excess plastic deformation stabilizing soil response.The process of obtaining the original chart has been improved. Algorithm based approximation is introduced. Pore pressure dependent ultimate bearing capacity normalization factor is introduced to normalize the chart.

  6. Method for controlling boiling point distribution of coal liquefaction oil product

    Science.gov (United States)

    Anderson, Raymond P.; Schmalzer, David K.; Wright, Charles H.

    1982-12-21

    The relative ratio of heavy distillate to light distillate produced in a coal liquefaction process is continuously controlled by automatically and continuously controlling the ratio of heavy distillate to light distillate in a liquid solvent used to form the feed slurry to the coal liquefaction zone, and varying the weight ratio of heavy distillate to light distillate in the liquid solvent inversely with respect to the desired weight ratio of heavy distillate to light distillate in the distillate fuel oil product. The concentration of light distillate and heavy distillate in the liquid solvent is controlled by recycling predetermined amounts of light distillate and heavy distillate for admixture with feed coal to the process in accordance with the foregoing relationships.

  7. Two-stage thermal/nonthermal waste treatment process

    International Nuclear Information System (INIS)

    Rosocha, L.A.; Anderson, G.K.; Coogan, J.J.; Kang, M.; Tennant, R.A.; Wantuck, P.J.

    1993-01-01

    An innovative waste treatment technology is being developed in Los Alamos to address the destruction of hazardous organic wastes. The technology described in this report uses two stages: a packed bed reactor (PBR) in the first stage to volatilize and/or combust liquid organics and a silent discharge plasma (SDP) reactor to remove entrained hazardous compounds in the off-gas to even lower levels. We have constructed pre-pilot-scale PBR-SDP apparatus and tested the two stages separately and in combined modes. These tests are described in the report

  8. Thermodynamic design of natural gas liquefaction cycles for offshore application

    Science.gov (United States)

    Chang, Ho-Myung; Lim, Hye Su; Choe, Kun Hyung

    2014-09-01

    A thermodynamic study is carried out for natural gas liquefaction cycles applicable to offshore floating plants, as partial efforts of an ongoing governmental project in Korea. For offshore liquefaction, the most suitable cycle may be different from the on-land LNG processes under operation, because compactness and simple operation are important as well as thermodynamic efficiency. As a turbine-based cycle, closed Claude cycle is proposed to use NG (natural gas) itself as refrigerant. The optimal condition for NG Claude cycle is determined with a process simulator (Aspen HYSYS), and the results are compared with fully-developed C3-MR (propane pre-cooled mixed refrigerant) JT cycles and various N2 (nitrogen) Brayton cycles in terms of efficiency and compactness. The newly proposed NG Claude cycle could be a good candidate for offshore LNG processes.

  9. Re-Condensation and Liquefaction of Helium and Hydrogen Using Coolers

    International Nuclear Information System (INIS)

    Green, Michael A.

    2009-01-01

    Coolers are used to cool cryogen free devices at temperatures from 5 to 30 K. Cryogen free cooling involves a temperature drop within the device being cooled and between the device and the cooler cold heads. Liquid cooling with a liquid cryogen distributed over the surface of a device combined with re-condensation can result in a much lower temperature drop between the cooler and the device being cooled. The next logical step beyond simple re-condensation is using a cooler to liquefy the liquid cryogen in the device. A number of tests of helium liquefaction and re-condensation of helium have been run using a pulse tube cooler in the drop-in mode. This report discusses the parameter space over which re-condensation and liquefaction for helium and hydrogen can occur.

  10. Comparison of Oone-Stage Free Gracilis Muscle Flap With Two-Stage Method in Chronic Facial Palsy

    Directory of Open Access Journals (Sweden)

    J Ghaffari

    2007-08-01

    Full Text Available Background:Rehabilitation of facial paralysis is one of the greatest challenges faced by reconstructive surgeons today. The traditional method for treatment of patients with facial palsy is the two-stage free gracilis flap which has a long latency period of between the two stages of surgery.Methods: In this paper, we prospectively compared the results of the one-stage gracilis flap method with the two -stage technique.Results:Out of 41 patients with facial palsy refered to Hazrat-e-Fatemeh Hospital 31 were selected from whom 22 underwent two- stage and 9 one-stage method treatment. The two groups were identical according to age,sex,intensity of illness, duration, and chronicity of illness. Mean duration of follow up was 37 months. There was no significant relation between the two groups regarding the symmetry of face in repose, smiling, whistling and nasolabial folds. Frequency of complications was equal in both groups. The postoperative surgeons and patients' satisfaction were equal in both groups. There was no significant difference between the mean excursion of muscle flap in one-stage (9.8 mm and two-stage groups (8.9 mm. The ratio of contraction of the affected side compared to the normal side was similar in both groups. The mean time of the initial contraction of the muscle flap in the one-stage group (5.5 months had a significant difference (P=0.001 with the two-stage one (6.5 months.The study revealed a highly significant difference (P=0.0001 between the mean waiting period from the first operation to the beginning of muscle contraction in one-stage(5.5 monthsand two-stage groups(17.1 months.Conclusion:It seems that the results and complication of the two methods are the same,but the one-stage method requires less time for facial reanimation,and is costeffective because it saves time and decreases hospitalization costs.

  11. Report on results of R and D of coal liquefaction technology in fiscal 1981; 1981 nendo sekitan ekika gijutsu no kenkyu kaihatsu seika setsumeisho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-03-01

    This paper explains the results of development of coal liquefaction technology under the Sunshine Project in fiscal 1981. In connection with solvent extraction and liquefaction, an 1 t/day experimental plant was completed for bituminous coals and operated continuously for 153 hours. An examination also started for the development of a 250 t/day pilot plant. As the element studies, R and D is in progress on the solvent extraction and liquefaction process, solid-liquid separation, secondary hydrogenation, and plant materials. In brown coals, the construction work of a 50 t/day pilot plant started for the purpose of establishing liquefaction technology for brown coal in Victoria State, Australia, with a part of the equipment manufactured. As the element studies, research was conducted on primary hydrogenation, deliming, secondary hydrogenation, dehydration and catalysts. In solvolysis liquefaction, a short-time concluding liquefaction reaction was continuously performed by a plant of 1 t/day scale. In direct hydro-liquefaction, a 2.4 t/day experimental plant was constructed, with the element studies conducted successively. In other words, researches were carried out by the bench scale plant on liquefaction, solid-liquid separation, iron-based catalysts, catalyst and reutilization, motive force recovery system by hydrohoist, and effect of preheating and deaeration. (NEDO)

  12. Contribution of wave-induced liquefaction in triggering hyperpycnal flows in Yellow River Estuary

    Science.gov (United States)

    Liu, X.; Jia, Y.

    2017-12-01

    Hyperpycnal flows, driven mainly by the gravity of near-bed negatively buoyant layers, are one of the most important processes for moving marine sediment across the earth. The issue of hyperpycnal flows existing in marine environment has drawn increasing scholars' attention since that was observed in situ off the Yellow River estuary in the 1980s. Most researches maintain that hyperpycnal flows in the Yellow River estuary are caused by the high-concentration sediments discharged from the Yellow River into sea, however, other mechanisms have been discounted since the sediment input from the river has been significantly changed due to climate and anthropogenic change. Here we demonstrate that wave-seabed interactions can generate hyperpycnal flows, without river input, by sediment flux convergence above an originally consolidated seabed. Using physical model experiments and multi-sensor field measurements, we characterize the composition-dependent liquefaction properties of the sediment due to wave-induced pore water pressure accumulation. This allows quantification of attenuation of sediment threshold velocity and critical shear stress (predominant variables in transport mechanics) during the liquefaction under waves. Parameterising the wave-seabed interactions in a new concept model shows that high waves propagating over the seabed sediment can act as a scarifier plough remoulding the seabed sediment. This contributes to marine hyperpycnal flows as the sediment is quickly resuspended under accumulating attenuation in strength. Therefore, the development of more integrative numerical models could supply realistic predictions of marine record in response to rising magnitude and frequency of storms.

  13. Bio-char derived from sewage sludge by liquefaction: Characterization and application for dye adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Leng, Lijian [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Yuan, Xingzhong, E-mail: yxz@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Huang, Huajun [School of Land Resources and Environment, Jiangxi Agricultural University, Nanchang 330045 (China); Shao, Jianguang; Wang, Hou [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China); Chen, Xiaohong [School of Business, Central South University, Changsha 410083 (China); Zeng, Guangming [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082 (China)

    2015-08-15

    Graphical abstract: - Highlights: • SS liquefaction bio-chars were effective on MG and MB removal from aqueous. • MG adsorption capacity depended strongly on carboxylic and phenolic groups. • Metal release accounted for nearly 30% of the total MG adsorbed on bio-chars. • Acetone and low temperature favor effective adsorbent production by liquefaction. - Abstract: Bio-chars produced by liquefaction of sewage sludge with methanol, ethanol, or acetone as the solvent at 260–380 °C were characterized in terms of their elemental composition, thermogravimetric characteristics, surface area and pore size distribution, and oxygen-containing functional groups composition. The surface area and total volume of the bio-chars were low, but the contents of oxygen-containing functional groups were high. The bio-chars were effective on Malachite green (MG) and Methylene blue (MB) removal from aqueous solution. The MG adsorption equilibrium data showed excellent fit to the Langmuir model and the kinetic data fitted well to the Pseudo-second-order model. Thermodynamic investigations indicated that MG adsorption on bio-char was spontaneous and endothermic. The MG adsorption mechanism appears to be associated with cation release and functional group participation. Additionally, liquefaction of SS with acetone as the solvent at low temperature (280 °C) would favor the production of bio-char adsorbent in terms of bio-char yield and MG and MB adsorption capacity.

  14. Thermodynamic design of hydrogen liquefaction systems with helium or neon Brayton refrigerator

    Science.gov (United States)

    Chang, Ho-Myung; Ryu, Ki Nam; Baik, Jong Hoon

    2018-04-01

    A thermodynamic study is carried out for the design of hydrogen liquefaction systems with helium (He) or neon (Ne) Brayton refrigerator. This effort is motivated by our immediate goal to develop a small-capacity (100 L/h) liquefier for domestic use in Korea. Eight different cycles are proposed and their thermodynamic performance is investigated in comparison with the existing liquefaction systems. The proposed cycles include the standard and modified versions of He Brayton refrigerators whose lowest temperature is below 20 K. The Brayton refrigerator is in direct thermal contact with the hydrogen flow at atmospheric pressure from ambient-temperature gas to cryogenic liquid. The Linde-Hampson system pre-cooled by a Ne Brayton refrigerator is also considered. Full cycle analysis is performed with the real properties of fluids to estimate the figure of merit (FOM) under an optimized operation condition. It is concluded that He Brayton refrigerators are feasible for this small-scale liquefaction, because a reasonably high efficiency can be achieved with simple and safe (low-pressure) operation. The complete cycles with He Brayton refrigerator are presented for the development of a prototype, including the ortho-to-para conversion.

  15. Investigation of bio-composites using Novolac type liquefied wood resin: effects of liquefaction and fabrication conditions

    Science.gov (United States)

    Hui Pan; Chung-Yun Hse; Todd F. Shupe

    2009-01-01

    Wood liquefaction using an organic solvent and an acid catalyst has long been studied as a novel technique to utilize biomass as an alternative to petroleum-based products. Oxalic acid is a weaker organic acid than a mineral acid and wood liquefaction with oxalic acid as a catalyst will result in a higher amount of wood residue than that with a mineral acid....

  16. One-stage versus two-stage exchange arthroplasty for infected total knee arthroplasty: a systematic review.

    Science.gov (United States)

    Nagra, Navraj S; Hamilton, Thomas W; Ganatra, Sameer; Murray, David W; Pandit, Hemant

    2016-10-01

    Infection complicating total knee arthroplasty (TKA) has serious implications. Traditionally the debate on whether one- or two-stage exchange arthroplasty is the optimum management of infected TKA has favoured two-stage procedures; however, a paradigm shift in opinion is emerging. This study aimed to establish whether current evidence supports one-stage revision for managing infected TKA based on reinfection rates and functional outcomes post-surgery. MEDLINE/PubMed and CENTRAL databases were reviewed for studies that compared one- and two-stage exchange arthroplasty TKA in more than ten patients with a minimum 2-year follow-up. From an initial sample of 796, five cohort studies with a total of 231 patients (46 single-stage/185 two-stage; median patient age 66 years, range 61-71 years) met inclusion criteria. Overall, there were no significant differences in risk of reinfection following one- or two-stage exchange arthroplasty (OR -0.06, 95 % confidence interval -0.13, 0.01). Subgroup analysis revealed that in studies published since 2000, one-stage procedures have a significantly lower reinfection rate. One study investigated functional outcomes and reported that one-stage surgery was associated with superior functional outcomes. Scarcity of data, inconsistent study designs, surgical technique and antibiotic regime disparities limit recommendations that can be made. Recent studies suggest one-stage exchange arthroplasty may provide superior outcomes, including lower reinfection rates and superior function, in select patients. Clinically, for some patients, one-stage exchange arthroplasty may represent optimum treatment; however, patient selection criteria and key components of surgical and post-operative anti-microbial management remain to be defined. III.

  17. Two Agendas for Bioethics: Critique and Integration.

    Science.gov (United States)

    Garrett, Jeremy R

    2015-07-01

    Many bioethicists view the primary task of bioethics as 'value clarification'. In this article, I argue that the field must embrace two more ambitious agendas that go beyond mere clarification. The first agenda, critique, involves unmasking, interrogating, and challenging the presuppositions that underlie bioethical discourse. These largely unarticulated premises establish the boundaries within which problems can be conceptualized and solutions can be imagined. The function of critique, then, is not merely to clarify these premises but to challenge them and the boundaries they define. The second agenda, integration, involves honoring and unifying what is right in competing values. Integration is the morally ideal response to value conflict, offering the potential for transcending win/lose outcomes. The function of integration, then, is to envision actions or policies that not only resolve conflicts, but that do so by jointly realizing many genuine values in deep and compelling ways. My argument proceeds in stages. After critically examining the role and dominant status of value clarification in bioethical discourse, I describe the nature and value of the two agendas, identify concrete examples of where each has been and could be successful, and explain why a critical integrative bioethics--one that appreciates the joint necessity and symbiotic potential of the two agendas--is crucial to the future of the field. The ultimate goal of all of this is to offer a more compelling vision for how bioethics might conduct itself within the larger intellectual and social world it seeks to understand and serve. © 2014 John Wiley & Sons Ltd.

  18. A two stage data envelopment analysis model with undesirable output

    Science.gov (United States)

    Shariff Adli Aminuddin, Adam; Izzati Jaini, Nur; Mat Kasim, Maznah; Nawawi, Mohd Kamal Mohd

    2017-09-01

    The dependent relationship among the decision making units (DMU) is usually assumed to be non-existent in the development of Data Envelopment Analysis (DEA) model. The dependency can be represented by the multi-stage DEA model, where the outputs from the precedent stage will be the inputs for the latter stage. The multi-stage DEA model evaluate both the efficiency score for each stages and the overall efficiency of the whole process. The existing multi stage DEA models do not focus on the integration with the undesirable output, in which the higher input will generate lower output unlike the normal desirable output. This research attempts to address the inclusion of such undesirable output and investigate the theoretical implication and potential application towards the development of multi-stage DEA model.

  19. Continuous bench-scale slurry catalyst testing direct coal liquefaction rawhide sub-bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, R.F.; Coless, L.A.; Davis, S.M. [and others

    1995-12-31

    In 1992, the Department of Energy (DOE) sponsored research to demonstrate a dispersed catalyst system using a combination of molybdenum and iron precursors for direct coal liquefaction. This dispersed catalyst system was successfully demonstrated using Black Thunder sub-bituminous coal at Wilsonville, Alabama by Southern Electric International, Inc. The DOE sponsored research continues at Exxon Research and Development Laboratories (ERDL). A six month continuous bench-scale program using ERDL`s Recycle Coal Liquefaction Unit (RCLU) is planned, three months in 1994 and three months in 1995. The initial conditions in RCLU reflect experience gained from the Wilsonville facility in their Test Run 263. Rawhide sub-bituminous coal which is similar to the Black Thunder coal tested at Wilsonville was used as the feed coal. A slate of five dispersed catalysts for direct coal liquefaction of Rawhide sub-bituminous coal has been tested. Throughout the experiments, the molybdenum addition rate was held constant at 100 wppm while the iron oxide addition rate was varied from 0.25 to 1.0 weight percent (dry coal basis). This report covers the 1994 operations and accomplishments.

  20. Technical and economic aspects of brown coal gasification and liquefaction

    International Nuclear Information System (INIS)

    Speich, P.

    1980-01-01

    A number of gasification and liquefaction processes for Rhenish brown coal are investigated along with the technical and economic aspects of coal beneficiation. The status of coal beneficiation and the major R + D activities are reviewed. (orig.) [de

  1. Bio-crude production from secondary pulp/paper-mill sludge and waste newspaper via co-liquefaction in hot-compressed water

    International Nuclear Information System (INIS)

    Zhang, Linghong; Champagne, Pascale; Xu, Chunbao

    2011-01-01

    Co-liquefaction of secondary pulp/paper-mill sludge (solids concentration: 1.6 wt%) and waste newspaper with a total solids concentration of 11.3 wt% was investigated with and without the addition of catalysts in a 75 ml Parr High-Pressure reactor at temperatures of 250-380 o C for 20 min. The yield of heavy oil (HO) without catalyst was between 16.7 and 28.0 wt% within this temperature range, and peaked at 350 o C. The addition of HCO 2 H, FeS, or KOH at 5 wt% of the total solids (on a dry basis) was found to enhance the HO yield at 300 o C, particularly HCO 2 H, which increased the yield of HO from 24.9 to 34.4 wt%. More interestingly, synergistic effects between secondary pulp/paper-mill sludge and waste newspaper were observed in the co-liquefaction operations. For example, the HO yield attained was 26.9 wt% at 300 o C in the co-liquefaction of the mixture of 33 wt% sludge and 67 wt% waste newspaper, and was noted to be 9 wt% and 6 wt% higher than the yields obtained from liquefaction of sludge and waste newspaper alone, respectively. The HOs from liquefaction or co-liquefaction at 300 o C for 20 min exhibited significantly higher energy contents (HHV ≥ 30 MJ/kg), almost doubled those (-tilde 16 MJ/kg) of the original feedstocks.

  2. Effect of ammoniacal nitrogen on one-stage and two-stage anaerobic digestion of food waste

    International Nuclear Information System (INIS)

    Ariunbaatar, Javkhlan; Scotto Di Perta, Ester; Panico, Antonio; Frunzo, Luigi; Esposito, Giovanni; Lens, Piet N.L.; Pirozzi, Francesco

    2015-01-01

    Highlights: • Almost 100% of the biomethane potential of food waste was recovered during AD in a two-stage CSTR. • Recirculation of the liquid fraction of the digestate provided the necessary buffer in the AD reactors. • A higher OLR (0.9 gVS/L·d) led to higher accumulation of TAN, which caused more toxicity. • A two-stage reactor is more sensitive to elevated concentrations of ammonia. • The IC 50 of TAN for the AD of food waste amounts to 3.8 g/L. - Abstract: This research compares the operation of one-stage and two-stage anaerobic continuously stirred tank reactor (CSTR) systems fed semi-continuously with food waste. The main purpose was to investigate the effects of ammoniacal nitrogen on the anaerobic digestion process. The two-stage system gave more reliable operation compared to one-stage due to: (i) a better pH self-adjusting capacity; (ii) a higher resistance to organic loading shocks; and (iii) a higher conversion rate of organic substrate to biomethane. Also a small amount of biohydrogen was detected from the first stage of the two-stage reactor making this system attractive for biohythane production. As the digestate contains ammoniacal nitrogen, re-circulating it provided the necessary alkalinity in the systems, thus preventing an eventual failure by volatile fatty acids (VFA) accumulation. However, re-circulation also resulted in an ammonium accumulation, yielding a lower biomethane production. Based on the batch experimental results the 50% inhibitory concentration of total ammoniacal nitrogen on the methanogenic activities was calculated as 3.8 g/L, corresponding to 146 mg/L free ammonia for the inoculum used for this research. The two-stage system was affected by the inhibition more than the one-stage system, as it requires less alkalinity and the physically separated methanogens are more sensitive to inhibitory factors, such as ammonium and propionic acid

  3. Staging of gastric adenocarcinoma using two-phase spiral CT: correlation with pathologic staging

    International Nuclear Information System (INIS)

    Seo, Tae Seok; Lee, Dong Ho; Ko, Young Tae; Lim, Joo Won

    1998-01-01

    To correlate the preoperative staging of gastric adenocarcinoma using two-phase spiral CT with pathologic staging. One hundred and eighty patients with gastric cancers confirmed during surgery underwent two-phase spiral CT, and were evaluated retrospectively. CT scans were obtained in the prone position after ingestion of water. Scans were performed 35 and 80 seconds after the start of infusion of 120mL of non-ionic contrast material with the speed of 3mL/sec. Five mm collimation, 7mm/sec table feed and 5mm reconstruction interval were used. T-and N-stage were determined using spiral CT images, without knowledge of the pathologic results. Pathologic staging was later compared with CT staging. Pathologic T-stage was T1 in 70 cases(38.9%), T2 in 33(18.3%), T3 in 73(40.6%), and T4 in 4(2.2%). Type-I or IIa elevated lesions accouted for 10 of 70 T1 cases(14.3%) and flat or depressed lesions(type IIb, IIc, or III) for 60(85.7%). Pathologic N-stage was NO in 85 cases(47.2%), N1 in 42(23.3%), N2 in 31(17.2%), and N3 in 22(12,2%). The detection rate of early gastric cancer using two-phase spiral CT was 100.0%(10 of 10 cases) among elevated lesions and 78.3%(47 of 60 cases) among flat or depressed lesions. With regard to T-stage, there was good correlation between CT image and pathology in 86 of 180 cases(47.8%). Overstaging occurred in 23.3%(42 of 180 cases) and understaging in 28.9%(52 of 180 cases). With regard to N-stage, good correlation between CT image and pathology was noted in 94 of 180 cases(52.2%). The rate of understaging(31.7%, 57 of 180 cases) was higher than that of overstaging(16.1%, 29 of 180 cases)(p<0.001). The detection rate of early gastric cancer using two-phase spiral CT was 81.4%, and there was no significant difference in detectability between elevated and depressed lesions. Two-phase spiral CT for determing the T-and N-stage of gastric cancer was not effective;it was accurate in abont 50% of cases understaging tended to occur.=20

  4. Frequency analysis of a two-stage planetary gearbox using two different methodologies

    Science.gov (United States)

    Feki, Nabih; Karray, Maha; Khabou, Mohamed Tawfik; Chaari, Fakher; Haddar, Mohamed

    2017-12-01

    This paper is focused on the characterization of the frequency content of vibration signals issued from a two-stage planetary gearbox. To achieve this goal, two different methodologies are adopted: the lumped-parameter modeling approach and the phenomenological modeling approach. The two methodologies aim to describe the complex vibrations generated by a two-stage planetary gearbox. The phenomenological model describes directly the vibrations as measured by a sensor fixed outside the fixed ring gear with respect to an inertial reference frame, while results from a lumped-parameter model are referenced with respect to a rotating frame and then transferred into an inertial reference frame. Two different case studies of the two-stage planetary gear are adopted to describe the vibration and the corresponding spectra using both models. Each case presents a specific geometry and a specific spectral structure.

  5. Integrated Circuit Design of 3 Electrode Sensing System Using Two-Stage Operational Amplifier

    Science.gov (United States)

    Rani, S.; Abdullah, W. F. H.; Zain, Z. M.; N, Aqmar N. Z.

    2018-03-01

    This paper presents the design of a two-stage operational amplifier(op amp) for 3-electrode sensing system readout circuits. The designs have been simulated using 0.13μm CMOS technology from Silterra (Malaysia) with Mentor graphics tools. The purpose of this projects is mainly to design a miniature interfacing circuit to detect the redox reaction in the form of current using standard analog modules. The potentiostat consists of several op amps combined together in order to analyse the signal coming from the 3-electrode sensing system. This op amp design will be used in potentiostat circuit device and to analyse the functionality for each module of the system.

  6. Simplified dynamic analysis to evaluate liquefaction-induced lateral deformation of earth slopes: a computational fluid dynamics approach

    Science.gov (United States)

    Jafarian, Yaser; Ghorbani, Ali; Ahmadi, Omid

    2014-09-01

    Lateral deformation of liquefiable soil is a cause of much damage during earthquakes, reportedly more than other forms of liquefaction-induced ground failures. Researchers have presented studies in which the liquefied soil is considered as viscous fluid. In this manner, the liquefied soil behaves as non-Newtonian fluid, whose viscosity decreases as the shear strain rate increases. The current study incorporates computational fluid dynamics to propose a simplified dynamic analysis for the liquefaction-induced lateral deformation of earth slopes. The numerical procedure involves a quasi-linear elastic model for small to moderate strains and a Bingham fluid model for large strain states during liquefaction. An iterative procedure is considered to estimate the strain-compatible shear stiffness of soil. The post-liquefaction residual strength of soil is considered as the initial Bingham viscosity. Performance of the numerical procedure is examined by using the results of centrifuge model and shaking table tests together with some field observations of lateral ground deformation. The results demonstrate that the proposed procedure predicts the time history of lateral ground deformation with a reasonable degree of precision.

  7. Highly Dispersed Pseudo-Homogeneous and Heterogeneous Catalysts Synthesized via Inverse Micelle Solutions for the Liquefaction of Coal

    Energy Technology Data Exchange (ETDEWEB)

    Hampden-Smith, M.; Kawola, J.S.; Martino, A.; Sault, A.G.; Yamanaka, S.A.

    1999-01-05

    The mission of this project was to use inverse micelle solutions to synthesize nanometer sized metal particles and test the particles as catalysts in the liquefaction of coal and other related reactions. The initial focus of the project was the synthesis of iron based materials in pseudo-homogeneous form. The frost three chapters discuss the synthesis, characterization, and catalyst testing in coal liquefaction and model coal liquefaction reactions of iron based pseudo-homogeneous materials. Later, we became interested in highly dispersed catalysts for coprocessing of coal and plastic waste. Bifunctional catalysts . to hydrogenate the coal and depolymerize the plastic waste are ideal. We began studying, based on our previously devised synthesis strategies, the synthesis of heterogeneous catalysts with a bifunctional nature. In chapter 4, we discuss the fundamental principles in heterogeneous catalysis synthesis with inverse micelle solutions. In chapter 5, we extend the synthesis of chapter 4 to practical systems and use the materials in catalyst testing. Finally in chapter 6, we return to iron and coal liquefaction now studied with the heterogeneous catalysts.

  8. A model experiment of liquefaction and fluid transport: quantifying the effect of permeability discontinuity

    Science.gov (United States)

    Yasuda, N.; Sumita, I.

    2013-12-01

    Model experiments of liquefaction of a water-saturated sand (quick sand) is commonly conducted in class and in public. Various phenomena caused by liquefaction are reproduced within a closed bottle containing push-pins (Nohguchi, 2004). Experiments for tilted and layered case have also been conducted (Peacock, 2006). However quantitative measurements of liquid transport in these experiments have rarely been made. Here we show that such measurements are possible by analyzing the video images taken during such experiments. In addition, we show that a simple physical model is capable of explaining the time scales needed to expel the interstitial liquid. An experimental cell (cross section 22.0 mm x 99.4 mm, height 107.6 mm) is filled with a granular matter and water. The lower 33.0 mm consists of a two-layered granular medium, the upper layer consists of fine particles and the lower layer consists of coarse particles, with particle sizes of 0.05 mm and 0.2 mm, respectively. Since permeability depends on the square of the particle size, the upper layer becomes a low-permeability layer. We liquefy the cell by an impulsive vibration and study how the liquid migrates afterwards. We also vary the particle size combinations (upper layer: 0.05-0.15 mm, lower layer: 0.15-0.6 mm) and the thickness ratio of the 2 layers, and study how the time scale of the liquid migration depends on these changeable parameters. In a two-layered medium, we find that the pore water which originated from the bottom layer temporary accumulates at the interface of the two layers, and then ascends through the upper layer in the form of horizontal sheet or vertical channels. We find that these two different discharge styles are controlled by the permeability ratio of the two layers. We study the temporal change of the thicknesses of the two layers and find that there are three stages; 1: the slope of the upper surface is leveled by the impulse, 2: the pore water is discharged from the bottom layer

  9. Hydrothermal liquefaction of barley straw to bio-crude oil

    DEFF Research Database (Denmark)

    Zhu, Zhe; Rosendahl, Lasse; Toor, Saqib

    2015-01-01

    Hydrothermal liquefaction (HTL) of barley straw with K2CO3 at different temperatures (280–400 C) was conducted and compared to optimize its process conditions; the aqueous phase as a co-product from this process was recycled to explore the feasibility of implementing wastewater reuse for bio...

  10. Study on hydrogen transfer in coal liquefaction by tritium and carbon-14 tracers

    International Nuclear Information System (INIS)

    Nitoh, Osamu; Kabe, Toshiaki; Kabe, Yaeko.

    1985-01-01

    For the analysis of mechanism of hydrogenation and cracking of coal, the liquefaction of Taiheiyo coal using tritium labeled gaseous hydrogen and tritium labeled tetralin with small amounts of carbon-14 labeled naphthalene has been studied. Taiheiyo coal(25g) was thermally decomposed in tetralin or naphthalene solvent(75g) at 400--440 0 C under the initial hydrogen pressure of 5.9MPa for 30min with Ni-Mo-Al 2 O 3 catalyst(0--5g). The reaction mixture in an autoclave was separated by filtration, distillation and solvent extraction. Produced gas, oils and the solvent were analyzed by gas chromatography. The tritium and carbon-14 contents of separated reaction products were measured with a liquid scintilation counter to study the hydrogen transfer mechanism. The distribution of reaction products and the amount of hydrogen transfer from gas or solvent to the products were also determined. In hydrogen donor solvent such as tetralin, the coal liquefaction yield was independent from the catalyst, but the catalyst was effective in hydrocracking of preasphaltene and asphaltene. In naphthalene solvent, the coal liquefaction reaction hardly occured in the absence of the catalyst, because hydrogen transfer from both the solvent and gaseous hydrogen was scarce. Tritium distribution in the reaction products showed that complicated hydrogen exchange reactions between gaseous hydrogen, coal liquids and solvent came out by the presence of coal liquids and catalyst. The very small amounts of carbon-14 transferred to the liquefaction products showed that carbon exchange or transfer between solvent and coal did not take place. (author)

  11. Study on the Control Algorithm of Two-Stage DC-DC Converter for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Changhao Piao

    2014-01-01

    Full Text Available The fast response, high efficiency, and good reliability are very important characteristics to electric vehicles (EVs dc/dc converters. Two-stage dc-dc converter is a kind of dc-dc topologies that can offer those characteristics to EVs. Presently, nonlinear control is an active area of research in the field of the control algorithm of dc-dc converters. However, very few papers research on two-stage converter for EVs. In this paper, a fixed switching frequency sliding mode (FSFSM controller and double-integral sliding mode (DISM controller for two-stage dc-dc converter are proposed. And a conventional linear control (lag is chosen as the comparison. The performances of the proposed FSFSM controller are compared with those obtained by the lag controller. In consequence, the satisfactory simulation and experiment results show that the FSFSM controller is capable of offering good large-signal operations with fast dynamical responses to the converter. At last, some other simulation results are presented to prove that the DISM controller is a promising method for the converter to eliminate the steady-state error.

  12. Renewable hydrocarbon fuels from hydrothermal liquefaction: A techno-economic analysis

    DEFF Research Database (Denmark)

    Pedersen, Thomas Helmer; Hansen, Nick Høy; Pérez, Oscar Miralles

    2018-01-01

    This study demonstrates the economic feasibility of producing renewable transportation drop-in fuels from lignocellulosic biomass through hydrothermal liquefaction and upgrading. An Aspen Plus® process model is developed based on extensive experimental data to document a techno-economic assessmen...

  13. Microwave-assisted liquefaction of wood with polyhydric alcohols and its application in preparation of polyurethane (PU) foams

    Science.gov (United States)

    Hui Pan; Zhifeng Zheng; Chung Y. Hse

    2011-01-01

    Microwave radiation was used as the heating source in southern pine wood liquefaction with PEG/glycerin binary solvent. It was found that microwave heating was more efficient than conventional oil bath heating for wood liquefaction. The wood residue content of the H2SO4 catalyzed liquefied wood dropped to zero within 5 min with microwave heating. The resulting...

  14. Novel bimetallic dispersed catalysts for temperature-programmed coal liquefaction. Technical progress report, October--December 1993

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, E.; Kirby, S.; Song, Chunshan; Schobert, H.H.

    1994-04-01

    Development of new catalysts is a promising approach to more, efficient coal liquefaction. It has been recognized that dispersed catalysts can be superior to supported catalysts for primary liquefaction of coals, because the control of initial coal dissolution or depolymerization requires infinite contact between the catalyst and coal. The primary objective of this research is to explore the potential of bimetallic dispersed catalysts from heterometallic molecular precursors in their use in model compound liquefaction reactions. This quarterly report describes the use of three precursors in model compound reactions. The first catalyst is a heterometallic complex consisting of two transition metals, Mo and Ni, and sulfur in a single molecule. The second is a thiocubane type complex consisting of cobalt, molybdenum and sulfur. The third is a thiocubane type cluster consisting of iron and sulfur and the fourth, the pure inorganic salt ammonium tetrathiomolybdate (ATM). It was found that the structure and the ligands in the model complexes affect the activity of the resulting catalyst significantly. The optimum reaction at a pressure of 6.9 MPa hydrogen gas varied for different catalysts. The bimetallic catalysts generated in situ from the organometallic precursor are more active than monometallic catalysts like ATTM and the thiocubane type cluster Fe{sub 4}. Main products are hydrogenated phenanthrene derivatives, like DBP, THP, sym-OHP, cis- and trans-unsym-OHP with minor isomerization products such as sym-OHA. Our results indicate that other transition metal and ligand combinations in the organometallic precursors and the use of another model compound could result in substantially higher conversion activity.

  15. Biotransformation of Domestic Wastewater Treatment Plant Sludge by Two-Stage Integrated Processes -Lsb & Ssb

    Directory of Open Access Journals (Sweden)

    Md. Zahangir Alam, A. H. Molla and A. Fakhru’l-Razi

    2012-10-01

    Full Text Available The study of biotransformation of domestic wastewater treatment plant (DWTP sludge was conducted in laboratory-scale by two-stage integrated process i.e. liquid state bioconversion (LSB and solid state bioconversion (SSB processes. The liquid wastewater sludge [4% w/w of total suspended solids (TSS] was treated by mixed filamentous fungi Penicillium corylophilum and Aspergillus niger, isolated, screened and mixed cultured in terms of their higher biodegradation potential to wastewater sludge. The biosolids was increased to about 10% w/w. Conversely, the soluble [i.e. Total dissolve solid (TDS] and insoluble substances (TSS in treated supernatant were decreased effectively in the LSB process. In the developed LSB process, 93.8 g kg-1of biosolids were enriched with fungal biomass protein and nutrients (NPK, and 98.8% of TSS, 98.2% of TDS, 97.3% of turbidity, 80.2% of soluble protein, 98.8% of reducing sugar and 92.7% of chemical oxygen demand (COD in treated sludge supernatant were removed after 8 days of treatment. Specific resistance to filtration (1.39x1012 m/kg was decreased tremendously by the microbial treatment of DWTP sludge after 6 days of fermentation. The treated biosolids in DWTP sludge was considered as pretreated resource materials for composting and converted into compost by SSB process. The SSB process was evaluated for composting by monitoring the microbial growth and its subsequent roles in biodegradation in composting bin (CB. The process was conducted using two mixed fungal cultures, Trichoderma harzianum with Phanerochaete chrysosporium 2094 and (T/P and T. harzianum and Mucor hiemalis (T/M; and two bulking materials, sawdust (SD and rice straw (RS. The most encouraging results of microbial growth and subsequent solid state bioconversion were exhibited in the RS than the SD. Significant decrease of the C/N ratio and germination index (GI were attained as well as the higher value of glucosamine was exhibited in compost; which

  16. Two-Stage Fuzzy Portfolio Selection Problem with Transaction Costs

    Directory of Open Access Journals (Sweden)

    Yanju Chen

    2015-01-01

    Full Text Available This paper studies a two-period portfolio selection problem. The problem is formulated as a two-stage fuzzy portfolio selection model with transaction costs, in which the future returns of risky security are characterized by possibility distributions. The objective of the proposed model is to achieve the maximum utility in terms of the expected value and variance of the final wealth. Given the first-stage decision vector and a realization of fuzzy return, the optimal value expression of the second-stage programming problem is derived. As a result, the proposed two-stage model is equivalent to a single-stage model, and the analytical optimal solution of the two-stage model is obtained, which helps us to discuss the properties of the optimal solution. Finally, some numerical experiments are performed to demonstrate the new modeling idea and the effectiveness. The computational results provided by the proposed model show that the more risk-averse investor will invest more wealth in the risk-free security. They also show that the optimal invested amount in risky security increases as the risk-free return decreases and the optimal utility increases as the risk-free return increases, whereas the optimal utility increases as the transaction costs decrease. In most instances the utilities provided by the proposed two-stage model are larger than those provided by the single-stage model.

  17. Wide-bandwidth bilateral control using two-stage actuator system

    International Nuclear Information System (INIS)

    Kokuryu, Saori; Izutsu, Masaki; Kamamichi, Norihiro; Ishikawa, Jun

    2015-01-01

    This paper proposes a two-stage actuator system that consists of a coarse actuator driven by a ball screw with an AC motor (the first stage) and a fine actuator driven by a voice coil motor (the second stage). The proposed two-stage actuator system is applied to make a wide-bandwidth bilateral control system without needing expensive high-performance actuators. In the proposed system, the first stage has a wide moving range with a narrow control bandwidth, and the second stage has a narrow moving range with a wide control bandwidth. By consolidating these two inexpensive actuators with different control bandwidths in a complementary manner, a wide bandwidth bilateral control system can be constructed based on a mechanical impedance control. To show the validity of the proposed method, a prototype of the two-stage actuator system has been developed and basic performance was evaluated by experiment. The experimental results showed that a light mechanical impedance with a mass of 10 g and a damping coefficient of 2.5 N/(m/s) that is an important factor to establish good transparency in bilateral control has been successfully achieved and also showed that a better force and position responses between a master and slave is achieved by using the proposed two-stage actuator system compared with a narrow bandwidth case using a single ball screw system. (author)

  18. Two-stage precipitation of neptunium (IV) oxalate

    International Nuclear Information System (INIS)

    Luerkens, D.W.

    1983-07-01

    Neptunium (IV) oxalate was precipitated using a two-stage precipitation system. A series of precipitation experiments was used to identify the significant process variables affecting precipitate characteristics. Process variables tested were input concentrations, solubility conditions in the first stage precipitator, precipitation temperatures, and residence time in the first stage precipitator. A procedure has been demonstrated that produces neptunium (IV) oxalate particles that filter well and readily calcine to the oxide

  19. Studies on liquefaction and pyrolysis of peat and biomass at KTH

    International Nuclear Information System (INIS)

    Bjoernbom, E.; Sjoestrom, K.; Hoernel, C.; Zanzi, R.; Bjoernbom, P.

    1996-01-01

    A brief review of the study on thermochemical conversion of solid fuels is done. The study have been performed in the Royal Institute of Technology, Stockholm, since the outbreak of energy crisis in the seventies. The main problems connected with utilisation of peat for energy are: 90% moisture content in the deposits and 35-40% oxygen content in the dry substance. Simultaneous dewatering and liquefaction of peat have been achieved by the Bjoerbom method. The wet peat has been treated with CO and H 2 O without preliminary drying, using water as a medium agent. After treatment water has been phase-separated from the heavy oil product. Another approach is de-oxygenation of peat prior to liquefaction. A significant part of oxygen in peat and biomass can be removed by thermal decomposition of the fuels prior to liquefaction and removal of carbon dioxide and water from the organic matter in them. The products obtained after de-oxygenation demand low consumption of external hydrogenation agent because they are rich in hydrogen. Some criteria for selection of peat as a raw material for liquefaction are given. The equipment and experimental procedure for pyrolysis of peat and biomass are described. A free fall tubular reactor with max operating pressure of 5 MPa and temperature of 1100 o C has been used. The effect of treatment conditions under the rapid pyrolysis in the free fall reactor on the yield and the reactivity of char obtained after the final pyrolysis is shown. Peat and wood are transformed into pyrolysis products for less than 1 second; 35-50% of the moisture- and ash-free peat and 70% of the wood have been converted into gaseous products.The char obtained in the rapid pyrolysis contains a fraction which can be further de-volatilized by slow pyrolysis for a few minutes - time much longer than the time for formation of primary products. High reactivity of char is favoured by lower pyrolysis temperature, shorter residence time and larger particle size of the fuel

  20. Non-enhanced CT versus contrast-enhanced CT in integrated PET/CT studies for nodal staging of rectal cancer

    International Nuclear Information System (INIS)

    Tateishi, Ukihide; Maeda, Tetsuo; Morimoto, Tsuyoshi; Miyake, Mototaka; Arai, Yasuaki; Kim, E.E.

    2007-01-01

    The purpose of the present study was to determine the diagnostic accuracy of non-enhanced CT and contrast-enhanced CT in integrated PET/CT studies for preoperative nodal staging of rectal cancer. Retrospective analysis was performed in 53 patients with pathologically proven rectal cancer who had been referred for preoperative staging. All patients underwent integrated PET/CT consisting of non-enhanced and contrast-enhanced CT followed by whole-body fluorine-18-fluorodeoxyglucose ([ 18 F]FDG) PET. Both non-enhanced and contrast-enhanced PET/CT images were evaluated separately by two observers in consensus. The reference standard was histopathologic results. For nodal staging of rectal cancer, we compared diagnostic accuracy on a per-patient basis between the two modalities. Nodal staging was correctly determined with non-enhanced studies in 37 patients (70%) and with contrast-enhanced studies in 42 patients (79%). On a per-patient basis, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of regional lymph node staging were 85%, 68%, 83%, 72%, and 79%, respectively, with contrast-enhanced studies, and 85%, 42%, 73%, 62%, and 70%, respectively, with non-enhanced studies. The difference in the accuracy of nodal staging between the two modalities was not significant (p = 0.063). Compared with non-enhanced studies, contrast-enhanced studies determined more correctly the status of pararectal lymph nodes (p 0.002), internal iliac lymph nodes (p = 0.004), and obturator lymph nodes (p < 0.0001). Contrast-enhanced PET/CT is superior to non-enhanced PET/CT for precise definition of regional nodal status in rectal cancer. (orig.)

  1. Hydrothermal co-liquefaction of microalgae, wood, and sugar beet pulp

    NARCIS (Netherlands)

    Brilman, D. W.F.; Drabik, N.; Wądrzyk, M.

    2017-01-01

    Hydrothermal co-liquefaction of mixed (wet and dry) biomass residue streams would greatly enhance the viability and scale up potential of the technology as platform in bioenergy and biorefinery applications. This study aims to identify possible interaction effects between three different feeds

  2. Prediction model of biocrude yield and nitrogen heterocyclic compounds analysis by hydrothermal liquefaction of microalgae with model compounds.

    Science.gov (United States)

    Sheng, Lili; Wang, Xin; Yang, Xiaoyi

    2018-01-01

    The model of biocrude yield and the nitrogen heterocyclic compounds in biocrude of microalgae hydrothermal liquefaction are two of the most concerned issues in this field at present. This study explored a hydrothermal liquefaction biocrude yield model involved in the interaction among biochemical compounds in microalgae and analysed nitrogen heterocyclic compounds in biocrude. The model compound (castor oil, soya protein and glucose) and Nanochloropsis were liquefied at 280°C for 1h. The products were analyzed by GC-MS, element analysis and FTIR. The results suggested that interactions among different components in microalgae enhanced biocrude yield. The biocrude yield prediction model involved cross-interactions performed more accurate than previous models.When the ratio of protein and carbohydrate around 3, the cross-interaction and nitrogen heterocyclic compounds in biocrude would both reach the highest extent. Copyright © 2017. Published by Elsevier Ltd.

  3. Effect of ammoniacal nitrogen on one-stage and two-stage anaerobic digestion of food waste

    Energy Technology Data Exchange (ETDEWEB)

    Ariunbaatar, Javkhlan, E-mail: jaka@unicas.it [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio 43, 03043 Cassino, FR (Italy); UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft (Netherlands); Scotto Di Perta, Ester [Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Via Claudio 21, 80125 Naples (Italy); Panico, Antonio [Telematic University PEGASO, Piazza Trieste e Trento, 48, 80132 Naples (Italy); Frunzo, Luigi [Department of Mathematics and Applications Renato Caccioppoli, University of Naples Federico II, Via Claudio, 21, 80125 Naples (Italy); Esposito, Giovanni [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio 43, 03043 Cassino, FR (Italy); Lens, Piet N.L. [UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft (Netherlands); Pirozzi, Francesco [Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Via Claudio 21, 80125 Naples (Italy)

    2015-04-15

    Highlights: • Almost 100% of the biomethane potential of food waste was recovered during AD in a two-stage CSTR. • Recirculation of the liquid fraction of the digestate provided the necessary buffer in the AD reactors. • A higher OLR (0.9 gVS/L·d) led to higher accumulation of TAN, which caused more toxicity. • A two-stage reactor is more sensitive to elevated concentrations of ammonia. • The IC{sub 50} of TAN for the AD of food waste amounts to 3.8 g/L. - Abstract: This research compares the operation of one-stage and two-stage anaerobic continuously stirred tank reactor (CSTR) systems fed semi-continuously with food waste. The main purpose was to investigate the effects of ammoniacal nitrogen on the anaerobic digestion process. The two-stage system gave more reliable operation compared to one-stage due to: (i) a better pH self-adjusting capacity; (ii) a higher resistance to organic loading shocks; and (iii) a higher conversion rate of organic substrate to biomethane. Also a small amount of biohydrogen was detected from the first stage of the two-stage reactor making this system attractive for biohythane production. As the digestate contains ammoniacal nitrogen, re-circulating it provided the necessary alkalinity in the systems, thus preventing an eventual failure by volatile fatty acids (VFA) accumulation. However, re-circulation also resulted in an ammonium accumulation, yielding a lower biomethane production. Based on the batch experimental results the 50% inhibitory concentration of total ammoniacal nitrogen on the methanogenic activities was calculated as 3.8 g/L, corresponding to 146 mg/L free ammonia for the inoculum used for this research. The two-stage system was affected by the inhibition more than the one-stage system, as it requires less alkalinity and the physically separated methanogens are more sensitive to inhibitory factors, such as ammonium and propionic acid.

  4. Two-Stage Multi-Objective Collaborative Scheduling for Wind Farm and Battery Switch Station

    Directory of Open Access Journals (Sweden)

    Zhe Jiang

    2016-10-01

    Full Text Available In order to deal with the uncertainties of wind power, wind farm and electric vehicle (EV battery switch station (BSS were proposed to work together as an integrated system. In this paper, the collaborative scheduling problems of such a system were studied. Considering the features of the integrated system, three indices, which include battery swapping demand curtailment of BSS, wind curtailment of wind farm, and generation schedule tracking of the integrated system are proposed. In addition, a two-stage multi-objective collaborative scheduling model was designed. In the first stage, a day-ahead model was built based on the theory of dependent chance programming. With the aim of maximizing the realization probabilities of these three operating indices, random fluctuations of wind power and battery switch demand were taken into account simultaneously. In order to explore the capability of BSS as reserve, the readjustment process of the BSS within each hour was considered in this stage. In addition, the stored energy rather than the charging/discharging power of BSS during each period was optimized, which will provide basis for hour-ahead further correction of BSS. In the second stage, an hour-ahead model was established. In order to cope with the randomness of wind power and battery swapping demand, the proposed hour-ahead model utilized ultra-short term prediction of the wind power and the battery switch demand to schedule the charging/discharging power of BSS in a rolling manner. Finally, the effectiveness of the proposed models was validated by case studies. The simulation results indicated that the proposed model could realize complement between wind farm and BSS, reduce the dependence on power grid, and facilitate the accommodation of wind power.

  5. Report on results for fiscal 1997 (B edition) on development of coal liquefaction technology. Development of bituminous coal liquefaction technology (research by pilot plant) 1/2; 1997 nendo sekitan ekika gijutsu kaihatsu seika hokokusho (B ban). Rekiseitan ekika gijutsu no kaihatsu (pilot plant ni yoru kenkyu) 2/2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-06-01

    This paper reports the operation of a pilot plant of a bituminous coal liquefaction technology as the 1/2 report. The operation research of the Run-2 through the Run-4-2 was conducted using, as the material, tanitoharum coal which is operating basis coal. The Run-2 achieved a coal charging continuous operation for 42 days. During the operation of 80% slurry supply load, various data were obtained including material balance under the NEDOL standard liquefaction conditions, with a liquefaction yield of 54% daf coal achieved. Steam blowing into the heating tube was found effective as measures to cope with coking generation in the heating furnace of a vacuum distillation tower. The softening point of liquefaction residuals was improved to 178 degrees C through the extracting adjustment of reduced pressure heavy gravity light oil fraction for washing. The Run-3/4-1 achieved a plant load ratio of 100% and a long-term coal charging continuous operation for 80 days, while the Run-3 achieved a slurry supply load of 100% under the NEDOL standard liquefaction conditions. The Run-4-1 achieved a high liquefaction yield of 58wt% daf coal. Performance was confirmed of a neutron beam source irradiation apparatus/measuring system and a tracer injection equipment. (NEDO)

  6. A Compact Two-Stage 120 W GaN High Power Amplifier for SweepSAR Radar Systems

    Science.gov (United States)

    Thrivikraman, Tushar; Horst, Stephen; Price, Douglas; Hoffman, James; Veilleux, Louise

    2014-01-01

    This work presents the design and measured results of a fully integrated switched power two-stage GaN HEMT high-power amplifier (HPA) achieving 60% power-added efficiency at over 120Woutput power. This high-efficiency GaN HEMT HPA is an enabling technology for L-band SweepSAR interferometric instruments that enable frequent repeat intervals and high-resolution imagery. The L-band HPA was designed using space-qualified state-of-the-art GaN HEMT technology. The amplifier exhibits over 34 dB of power gain at 51 dBm of output power across an 80 MHz bandwidth. The HPA is divided into two stages, an 8 W driver stage and 120 W output stage. The amplifier is designed for pulsed operation, with a high-speed DC drain switch operating at the pulsed-repetition interval and settles within 200 ns. In addition to the electrical design, a thermally optimized package was designed, that allows for direct thermal radiation to maintain low-junction temperatures for the GaN parts maximizing long-term reliability. Lastly, real radar waveforms are characterized and analysis of amplitude and phase stability over temperature demonstrate ultra-stable operation over temperature using integrated bias compensation circuitry allowing less than 0.2 dB amplitude variation and 2 deg phase variation over a 70 C range.

  7. Subtask 3.9 - Direct Coal Liquefaction Process Development

    Energy Technology Data Exchange (ETDEWEB)

    Aulich, Ted; Sharma, Ramesh

    2012-07-01

    The Energy and Environmental Research Center (EERC), in partnership with the U.S. Department of Energy (DOE) and Accelergy Corporation, an advanced fuels developer with technologies exclusively licensed from ExxonMobil, undertook Subtask 3.9 to design, build, and preliminarily operate a bench-scale direct coal liquefaction (DCL) system capable of converting 45 pounds/hour of pulverized, dried coal to a liquid suitable for upgrading to fuels and/or chemicals. Fabrication and installation of the DCL system and an accompanying distillation system for off-line fractionation of raw coal liquids into 1) a naphtha middle distillate stream for upgrading and 2) a recycle stream was completed in May 2012. Shakedown of the system was initiated in July 2012. In addition to completing fabrication of the DCL system, the project also produced a 500-milliliter sample of jet fuel derived in part from direct liquefaction of Illinois No. 6 coal, and submitted the sample to the Air Force Research Laboratory (AFRL) at Wright Patterson Air Force Base, Dayton, Ohio, for evaluation. The sample was confirmed by AFRL to be in compliance with all U.S. Air Force-prescribed alternative aviation fuel initial screening criteria.

  8. Indirect liquefaction of coal. [Coal gasification plus Fischer-Tropsch, methanol or Mobil M-gasoline process

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-06-30

    The most important potential environmental problems uniquely associated with indirect liquefaction appear to be related to the protection of occupational personnel from the toxic and carcinogenic properties of process and waste stream constituents, the potential public health risks from process products, by-products and emissions and the management of potentially hazardous solid wastes. The seriousness of these potential problems is related partially to the severity of potential effects (i.e., human mortality and morbidity), but even more to the uncertainty regarding: (1) the probable chemical characteristics and quantities of process and waste streams; and (2) the effectiveness and efficiencies of control technologies not yet tested on a commercial scale. Based upon current information, it is highly improbable that these potential problems will actually be manifested or pose serious constraints to the development of indirect liquefaction technologies, although their potential severity warrants continued research and evaluation. The siting of indirect liquefaction facilities may be significantly affected by existing federal, state and local regulatory requirements. The possibility of future changes in environmental regulations also represents an area of uncertainty that may develop into constraints for the deployment of indirect liquefaction processes. Out of 20 environmental issues identified as likely candidates for future regulatory action, 13 were reported to have the potential to impact significantly the commercialization of coal synfuel technologies. These issues are listed.

  9. Two-stage dental implants inserted in a one-stage procedure : a prospective comparative clinical study

    NARCIS (Netherlands)

    Heijdenrijk, Kees

    2002-01-01

    The results of this study indicate that dental implants designed for a submerged implantation procedure can be used in a single-stage procedure and may be as predictable as one-stage implants. Although one-stage implant systems and two-stage.

  10. Assessment of thermodynamic models for the design, analysis and optimisation of gas liquefaction systems

    International Nuclear Information System (INIS)

    Nguyen, Tuong-Van; Elmegaard, Brian

    2016-01-01

    Highlights: • Six thermodynamic models used for evaluating gas liquefaction systems are compared. • Three gas liquefaction systems are modelled, assessed and optimised for each equation of state. • The predictions of thermophysical properties and energy flows are significantly different. • The GERG-2008 model is the only consistent one, while cubic, virial and statistical equations are unsatisfying. - Abstract: Natural gas liquefaction systems are based on refrigeration cycles – they consist of the same operations such as heat exchange, compression and expansion, but they have different layouts, components and working fluids. The design of these systems requires a preliminary simulation and evaluation of their performance. However, the thermodynamic models used for this purpose are characterised by different mathematical formulations, ranges of application and levels of accuracy. This may lead to inconsistent results when estimating hydrocarbon properties and assessing the efficiency of a given process. This paper presents a thorough comparison of six equations of state widely used in the academia and industry, including the GERG-2008 model, which has recently been adopted as an ISO standard for natural gases. These models are used to (i) estimate the thermophysical properties of a Danish natural gas, (ii) simulate, and (iii) optimise liquefaction systems. Three case studies are considered: a cascade layout with three pure refrigerants, a single mixed-refrigerant unit, and an expander-based configuration. Significant deviations are found between all property models, and in all case studies. The main discrepancies are related to the prediction of the energy flows (up to 7%) and to the heat exchanger conductances (up to 11%), and they are not systematic errors. The results illustrate the superiority of using the GERG-2008 model for designing gas processes in real applications, with the aim of reducing their energy use. They demonstrate as well that

  11. Effect of process parameters on hydrothermal liquefaction of oil palm biomass for bio-oil production and its life cycle assessment

    International Nuclear Information System (INIS)

    Chan, Yi Herng; Yusup, Suzana; Quitain, Armando T.; Tan, Raymond R.; Sasaki, Mitsuru; Lam, Hon Loong; Uemura, Yoshimitsu

    2015-01-01

    Highlights: • Water is used as a clean solvent to liquefy palm biomass to bio-oil. • The optimum liquefaction condition of oil palm biomass is 390 °C and 25 MPa. • Optimum reaction time for liquefaction of empty fruit bunch and palm mesocarp fiber is 120 min. • Optimum reaction time for liquefaction of palm kernel shell is 240 min. • From the life cycle assessment, a net 2.29 kg CO 2 equivalent is generated per kg of bio-oil produced. - Abstract: This paper presents the studies on the effect of three process parameters; temperature, pressure and reaction time on the subcritical and supercritical hydrothermal liquefaction of oil palm empty fruit bunch, palm mesocarp fiber and palm kernel shell. The effect of temperature (330–390 °C), pressure (25–35 MPa) and reaction time (30–240 min) on bio-oil yields were investigated using a Inconel batch reactor. The optimum liquefaction condition for empty fruit bunch, palm mesocarp fiber and palm kernel shell was at supercritical condition of water; 390 °C and 25 MPa. For the effect of reaction time, bio-oil from empty fruit bunch and palm mesocarp fiber attained maximum yields at 120 min, whereas bio-oil yield from palm kernel shell continued to increase at reaction time of 240 min. Lastly, a life cycle assessment based on a conceptual biomass hydrothermal liquefaction process for bio-oil production was constructed and presented

  12. Simulation and statistical analysis for the optimization of nitrogen liquefaction plant with cryogenic Claude cycle using process modeling tool: ASPEN HYSYS

    International Nuclear Information System (INIS)

    Joshi, D.M.

    2017-01-01

    Cryogenic technology is used for liquefaction of many gases and it has several applications in food process engineering. Temperatures below 123 K are considered to be in the field of cryogenics. Extreme low temperatures are a basic need for many industrial processes and have several applications, such as superconductivity of magnets, space, medicine and gas industries. Several methods can be used to obtain the low temperatures required for liquefaction of gases. The process of cooling or refrigerating a gas to a temperature below its critical temperature so that liquid can be formed at some suitable pressure, which is below the critical pressure, is the basic liquefaction process. Different cryogenic cycle configurations are designed for getting the liquefied form of gases at different temperatures. Each of the cryogenic cycles like Linde cycle, Claude cycle, Kapitza cycle or modified Claude cycle has its own advantages and disadvantages. The placement of heat exchangers, Joule-Thompson valve and turboexpander decides the configuration of a cryogenic cycle. Each configuration has its own efficiency according to the application. Here, a nitrogen liquefaction plant is used for the analysis purpose. The process modeling tool ASPEN HYSYS can provide a software simulation approach before the actual implementation of the plant in the field. This paper presents the simulation and statistical analysis of the Claude cycle with the process modeling tool ASPEN HYSYS. It covers the technique used to optimize the liquefaction of the plant. The simulation results so obtained can be used as a reference for the design and optimization of the nitrogen liquefaction plant. Efficient liquefaction will give the best performance and productivity to the plant.

  13. Simulation and statistical analysis for the optimization of nitrogen liquefaction plant with cryogenic Claude cycle using process modeling tool: ASPEN HYSYS

    Science.gov (United States)

    Joshi, D. M.

    2017-09-01

    Cryogenic technology is used for liquefaction of many gases and it has several applications in food process engineering. Temperatures below 123 K are considered to be in the field of cryogenics. Extreme low temperatures are a basic need for many industrial processes and have several applications, such as superconductivity of magnets, space, medicine and gas industries. Several methods can be used to obtain the low temperatures required for liquefaction of gases. The process of cooling or refrigerating a gas to a temperature below its critical temperature so that liquid can be formed at some suitable pressure, which is below the critical pressure, is the basic liquefaction process. Different cryogenic cycle configurations are designed for getting the liquefied form of gases at different temperatures. Each of the cryogenic cycles like Linde cycle, Claude cycle, Kapitza cycle or modified Claude cycle has its own advantages and disadvantages. The placement of heat exchangers, Joule-Thompson valve and turboexpander decides the configuration of a cryogenic cycle. Each configuration has its own efficiency according to the application. Here, a nitrogen liquefaction plant is used for the analysis purpose. The process modeling tool ASPEN HYSYS can provide a software simulation approach before the actual implementation of the plant in the field. This paper presents the simulation and statistical analysis of the Claude cycle with the process modeling tool ASPEN HYSYS. It covers the technique used to optimize the liquefaction of the plant. The simulation results so obtained can be used as a reference for the design and optimization of the nitrogen liquefaction plant. Efficient liquefaction will give the best performance and productivity to the plant.

  14. Comparative assessment of single-stage and two-stage anaerobic digestion for the treatment of thin stillage.

    Science.gov (United States)

    Nasr, Noha; Elbeshbishy, Elsayed; Hafez, Hisham; Nakhla, George; El Naggar, M Hesham

    2012-05-01

    A comparative evaluation of single-stage and two-stage anaerobic digestion processes for biomethane and biohydrogen production using thin stillage was performed to assess the impact of separating the acidogenic and methanogenic stages on anaerobic digestion. Thin stillage, the main by-product from ethanol production, was characterized by high total chemical oxygen demand (TCOD) of 122 g/L and total volatile fatty acids (TVFAs) of 12 g/L. A maximum methane yield of 0.33 L CH(4)/gCOD(added) (STP) was achieved in the two-stage process while a single-stage process achieved a maximum yield of only 0.26 L CH(4)/gCOD(added) (STP). The separation of acidification stage increased the TVFAs to TCOD ratio from 10% in the raw thin stillage to 54% due to the conversion of carbohydrates into hydrogen and VFAs. Comparison of the two processes based on energy outcome revealed that an increase of 18.5% in the total energy yield was achieved using two-stage anaerobic digestion. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Design optimization of single mixed refrigerant natural gas liquefaction process using the particle swarm paradigm with nonlinear constraints

    International Nuclear Information System (INIS)

    Khan, Mohd Shariq; Lee, Moonyong

    2013-01-01

    The particle swarm paradigm is employed to optimize single mixed refrigerant natural gas liquefaction process. Liquefaction design involves multivariable problem solving and non-optimal execution of these variables can waste energy and contribute to process irreversibilities. Design optimization requires these variables to be optimized simultaneously; minimizing the compression energy requirement is selected as the optimization objective. Liquefaction is modeled using Honeywell UniSim Design ™ and the resulting rigorous model is connected with the particle swarm paradigm coded in MATLAB. Design constraints are folded into the objective function using the penalty function method. Optimization successfully improved efficiency by reducing the compression energy requirement by ca. 10% compared with the base case. -- Highlights: ► The particle swarm paradigm (PSP) is employed for design optimization of SMR NG liquefaction process. ► Rigorous SMR process model based on UniSim is connected with PSP coded in MATLAB. ► Stochastic features of PSP give more confidence in the optimality of complex nonlinear problems. ► Optimization with PSP notably improves energy efficiency of the SMR process.

  16. Research on mechanism of and catalysts for extraction liquefaction of coal using coal-based solvents; Sekitankei yozai ni yoru sekitan no chushutsu ekika kiko to shokubai no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-07-01

    Papers of Professor Yoshio Kamiya of Tokyo University are compiled into this report. The list of the papers includes (1) Synthesis of heavy fuel oils from coal; (2) Research and development of coal liquefaction; (3) Dissolution reaction of coal by hydrogen-donating aromatic solvents (I); (4) Effect of hydrogen-donor solvent on the liquefaction of coal; (5) Recent studies on the chemical structure of solvent refined coal; (6) Dissolution reaction of coal by hydrogen-donating aromatic solvents (II); (7) Future of coal as energy material; (8), (9), (10) same as (6) in the subject discussed; (11) Recent studies on coal liquefaction catalysts; (12) Environmental problems and drain treatment to accompany processes of converting fossil resources into fuels; (13) Chemistry of coal oxidation; (14) Fractionation and analysis of solvent refined coal by gel permeation chromatography; (15) Current state of research and development of coal liquefaction; (16) Properties and components of coal oils from coal liquefaction processes under development; (17) Solvent effect of coal derived aromatic compounds on the liquefaction of Akabira coal; (18) Chemistry of coal liquefaction; (19) Research and development of coal liquefaction in the U.S.; (20) Thermal treatment of coal-related aromatic ethers in tetralin solution; (21) Recent technology of utilizing heavy carbon resources; (22) Chemical properties and reactivity of coal; (23) Current state and future of development of coal liquefaction processes; and (24) Development of overseas coal liquefaction projects. (NEDO)

  17. Biological production of alcohols from coal through indirect liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Barik, S; Prieto, S; Harrison, S B; Clausen, E C; Gaddy, J L

    1988-08-01

    The purpose of this project is to demonstrate the feasibility of producing liquid fuels from the components of synthesis gas through biological indirect liquefaction. The results of pure culture and natural source screening studies aimed at finding organisms capable of carrying out the conversions are presented and discussed. 17 refs., 2 figs., 8 tabs.

  18. Fiscal 1995 report. Liquefaction key technology subcommittee; 1995 nendo ekika kiban gijutsu bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The subcommittee held the 1st meeting in September 1955 and the 2nd in March 1996, when fiscal 1995 research plans and research results were introduced and deliberated. In the study for designing a high-dispersion catalyst and the elucidation of the mechanism of activity expression, catalysts of highly dispersed iron supported on the brown coal surface in various ways were compared with each other in terms of liquefaction activity. Furthermore, geometric changes in the iron catalyst during the sulfurizing process were examined using the XRD (X-ray diffraction) and TEM (transient electromagnetic) methods. An improved catalyst was found to achieve a liquefaction yield near the Yallourn coal liquefaction limit in a high boiling solvent system. Concerning the study of coal oil product applications and refining technologies, reports were delivered on research results relating to the problem of blocking to occur during naphtha fraction refining and measures therefor, inhibition of active metal geometric changes during reaction, methods for separating hetero-compounds from coal oil and application thereof, and so forth. (NEDO)

  19. Condensate from a two-stage gasifier

    DEFF Research Database (Denmark)

    Bentzen, Jens Dall; Henriksen, Ulrik Birk; Hindsgaul, Claus

    2000-01-01

    Condensate, produced when gas from downdraft biomass gasifier is cooled, contains organic compounds that inhibit nitrifiers. Treatment with activated carbon removes most of the organics and makes the condensate far less inhibitory. The condensate from an optimised two-stage gasifier is so clean...... that the organic compounds and the inhibition effect are very low even before treatment with activated carbon. The moderate inhibition effect relates to a high content of ammonia in the condensate. The nitrifiers become tolerant to the condensate after a few weeks of exposure. The level of organic compounds...... and the level of inhibition are so low that condensate from the optimised two-stage gasifier can be led to the public sewer....

  20. Evidence of two-stage melting of Wigner solids

    Science.gov (United States)

    Knighton, Talbot; Wu, Zhe; Huang, Jian; Serafin, Alessandro; Xia, J. S.; Pfeiffer, L. N.; West, K. W.

    2018-02-01

    Ultralow carrier concentrations of two-dimensional holes down to p =1 ×109cm-2 are realized. Remarkable insulating states are found below a critical density of pc=4 ×109cm-2 or rs≈40 . Sensitive dc V-I measurement as a function of temperature and electric field reveals a two-stage phase transition supporting the melting of a Wigner solid as a two-stage first-order transition.

  1. Development of advanced air-blown entrained-flow two-stage bituminous coal IGCC gasifier

    Directory of Open Access Journals (Sweden)

    Abaimov Nikolay A.

    2017-01-01

    Full Text Available Integrated gasification combined cycle (IGCC technology has two main advantages: high efficiency, and low levels of harmful emissions. Key element of IGCC is gasifier, which converts solid fuel into a combustible synthesis gas. One of the most promising gasifiers is air-blown entrained-flow two-stage bituminous coal gasifier developed by Mitsubishi Heavy Industries (MHI. The most obvious way to develop advanced gasifier is improvement of commercial-scale 1700 t/d MHI gasifier using the computational fluid dynamics (CFD method. Modernization of commercial-scale 1700 t/d MHI gasifier is made by changing the regime parameters in order to improve its cold gas efficiency (CGE and environmental performance, namely H2/CO ratio. The first change is supply of high temperature (900°C steam in gasifier second stage. And the second change is additional heating of blast air to 900°C.

  2. Design and control of a decoupled two degree of freedom translational parallel micro-positioning stage.

    Science.gov (United States)

    Lai, Lei-Jie; Gu, Guo-Ying; Zhu, Li-Min

    2012-04-01

    This paper presents a novel decoupled two degrees of freedom (2-DOF) translational parallel micro-positioning stage. The stage consists of a monolithic compliant mechanism driven by two piezoelectric actuators. The end-effector of the stage is connected to the base by four independent kinematic limbs. Two types of compound flexure module are serially connected to provide 2-DOF for each limb. The compound flexure modules and mirror symmetric distribution of the four limbs significantly reduce the input and output cross couplings and the parasitic motions. Based on the stiffness matrix method, static and dynamic models are constructed and optimal design is performed under certain constraints. The finite element analysis results are then given to validate the design model and a prototype of the XY stage is fabricated for performance tests. Open-loop tests show that maximum static and dynamic cross couplings between the two linear motions are below 0.5% and -45 dB, which are low enough to utilize the single-input-single-out control strategies. Finally, according to the identified dynamic model, an inversion-based feedforward controller in conjunction with a proportional-integral-derivative controller is applied to compensate for the nonlinearities and uncertainties. The experimental results show that good positioning and tracking performances are achieved, which verifies the effectiveness of the proposed mechanism and controller design. The resonant frequencies of the loaded stage at 2 kg and 5 kg are 105 Hz and 68 Hz, respectively. Therefore, the performance of the stage is reasonably good in term of a 200 N load capacity. © 2012 American Institute of Physics

  3. One-stage and two-stage penile buccal mucosa urethroplasty

    African Journals Online (AJOL)

    G. Barbagli

    2015-12-02

    Dec 2, 2015 ... there also seems to be a trend of decreasing urethritis and an increase of instrumentation and catheter related strictures in these countries as well [4–6]. The repair of penile urethral strictures may require one- or two- stage urethroplasty [7–10]. Certainly, sexual function can be placed at risk by any surgery ...

  4. Two-Stage Variable Sample-Rate Conversion System

    Science.gov (United States)

    Tkacenko, Andre

    2009-01-01

    A two-stage variable sample-rate conversion (SRC) system has been pro posed as part of a digital signal-processing system in a digital com munication radio receiver that utilizes a variety of data rates. The proposed system would be used as an interface between (1) an analog- todigital converter used in the front end of the receiver to sample an intermediatefrequency signal at a fixed input rate and (2) digita lly implemented tracking loops in subsequent stages that operate at v arious sample rates that are generally lower than the input sample r ate. This Two-Stage System would be capable of converting from an input sample rate to a desired lower output sample rate that could be var iable and not necessarily a rational fraction of the input rate.

  5. Integrative EEG biomarkers predict progression to Alzheimer's disease at the MCI stage

    Directory of Open Access Journals (Sweden)

    Simon-Shlomo ePoil

    2013-10-01

    Full Text Available Alzheimer's disease (AD is a devastating disorder of increasing prevalence in modern society. Mild cognitive impairment (MCI is considered a transitional stage between normal aging and AD; however, not all subjects with MCI progress to AD. Prediction of conversion to AD at an early stage would enable an earlier, and potentially more effective, treatment of AD. Electroencephalography (EEG biomarkers would provide a non-invasive and relatively cheap screening tool to predict conversion to AD; however, traditional EEG biomarkers have not been considered accurate enough to be useful in clinical practice. Here, we aim to combine the information from multiple EEG biomarkers into a diagnostic classification index in order to improve the accuracy of predicting conversion from MCI to AD within a two-year period. We followed 86 patients initially diagnosed with MCI for two years during which 25 patients converted to AD. We show that multiple EEG biomarkers mainly related to activity in the beta-frequency range (13–30 Hz can predict conversion from MCI to AD. Importantly, by integrating six EEG biomarkers into a diagnostic index using logistic regression the prediction improved compared with the classification using the individual biomarkers, with a sensitivity of 88% and specificity of 82%, compared with a sensitivity of 64% and specificity of 62% of the best individual biomarker in this index. In order to identify this diagnostic index we developed a data mining approach implemented in the Neurophysiological Biomarker Toolbox (http://www.nbtwiki.net/. We suggest that this approach can be used to identify optimal combinations of biomarkers (integrative biomarkers also in other modalities. Potentially, these integrative biomarkers could be more sensitive to disease progression and response to therapeutic intervention.

  6. Advanced Direct Liquefaction Concepts for PETC Generic Units - Phase II

    Energy Technology Data Exchange (ETDEWEB)

    None

    1997-09-01

    Reported here are the results of Laboratory and Bench- Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE- AC22- 91PC91040 during the period April 1, 1997 to June 30, 1997. This contract is with the University of Kentucky Research Foundation which supports work with the University of Kentucky Center for Applied Energy Research, CONSOL, Inc., LDP Associates, and Hydrocarbon Technologies, Inc. This work involves the introduction into the basic two stage liquefaction process several novel concepts which includes dispersed lower- cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. This report includes a data analysis of the ALC- 2 run which was the second continuous run in which Wyodak Black Thunder coal was fed to a two kg/ h bench- scale unit. One of the objectives of that run was to determine the relative activity of several Mo- based coal impregnated catalyst precursors. The precursors included ammonium heptamolybdate (100 mg Mo/ kg dry coal), which was used alone as well as in combination with ferrous sulfate (1% Fe/ dry coal) and nickel sulfate (50 mg Ni/ kg dry coal). The fourth precursor that was tested was phosphomolybdic acid which was used at a level of 100 mg Mo/ kg dry coal. Because of difficulties in effectively separating solids from the product stream, considerable variation in the feed stream occurred. Although the coal feed rate was nearly constant, the amount of recycle solvent varied which resulted in wide variations of resid, unconverted coal and mineral matter in the feed stream. Unfortunately, steady state was not achieved in any of the four conditions that were run. Earlier it was reported that Ni- Mo catalyst appeared to give the best results based upon speculative steady- state yields that were developed.

  7. Reflections on Centaur Upper Stage Integration by the NASA Lewis (Glenn) Research Center

    Science.gov (United States)

    Graham, Scott R.

    2015-01-01

    The NASA Glenn (then Lewis) Research Center (GRC) led several expendable launch vehicle (ELV) projects from 1963 to 1998, most notably the Centaur upper stage. These major, comprehensive projects included system management, system development, integration (both payload and stage), and launch operations. The integration role that GRC pioneered was truly unique and highly successful. Its philosophy, scope, and content were not just invaluable to the missions and vehicles it supported, but also had significant Agency-wide benefits. An overview of the NASA Lewis Research Center (now the NASA Glenn Research Center) philosophy on ELV integration is provided, focusing on Atlas/Centaur, Titan/Centaur, and Shuttle/Centaur vehicles and programs. The necessity of having a stable, highly technically competent in-house staff is discussed. Significant depth of technical penetration of contractor work is another critical component. Functioning as a cohesive team was more than a concept: GRC senior management, NASA Headquarters, contractors, payload users, and all staff worked together. The scope, content, and history of launch vehicle integration at GRC are broadly discussed. Payload integration is compared to stage development integration in terms of engineering and organization. Finally, the transition from buying launch vehicles to buying launch services is discussed, and thoughts on future possibilities of employing the successful GRC experience in integrating ELV systems like Centaur are explored.

  8. Thermostable endoglucanases in the liquefaction of hydrothermally pretreated wheat straw

    Directory of Open Access Journals (Sweden)

    Siika-aho Matti

    2011-01-01

    Full Text Available Abstract Background Thermostable enzymes have several benefits in lignocellulose processing. In particular, they potentially allow the use of increased substrate concentrations (because the substrate viscosity decreases as the temperature increases, resulting in improved product yields and reduced capital and processing costs. A short pre-hydrolysis step at an elevated temperature using thermostable enzymes aimed at rapid liquefaction of the feedstock is seen as an attractive way to overcome the technical problems (such as poor mixing and mass transfer properties connected with high initial solid loadings in the lignocellulose to ethanol process. Results The capability of novel thermostable enzymes to reduce the viscosity of high-solid biomass suspensions using a real-time viscometric measurement method was investigated. Heterologously expressed enzymes from various thermophilic organisms were compared for their ability to liquefy the lignocellulosic substrate, hydrothermally pretreated wheat straw. Once the best enzymes were identified, the optimal temperatures for these enzymes to decrease substrate viscosity were compared. The combined hydrolytic properties of the thermostable preparations were tested in hydrolysis experiments. The studied mixtures were primarily designed to have good liquefaction potential, and therefore contained an enhanced proportion of the key liquefying enzyme, EGII/Cel5A. Conclusions Endoglucanases were shown to have a superior ability to rapidly reduce the viscosity of the 15% (w/w; dry matter hydrothermally pretreated wheat straw. Based on temperature profiling studies, Thermoascus aurantiacus EGII/Cel5A was the most promising enzyme for biomass liquefaction. Even though they were not optimized for saccharification, many of the thermostable enzyme mixtures had superior hydrolytic properties compared with the commercial reference enzymes at 55°C.

  9. Assessment of wood liquefaction in acidified ethylene glycol using experimental design methodology

    Energy Technology Data Exchange (ETDEWEB)

    Rezzoug, S.A. [Universite de La Rochelle, Lab. de Maitrise des Technologies Agro-Industrielles, La Rochelle, 17 (France); Capart, R. [Universite de Technologie de Compiegne, Dept. de Genie Chimique, Compiegne, 60 (France)

    2003-03-01

    The liquefaction of milled wood (Pinus pinaster) was effected in ethylene glycol acidified with small quantities of H{sub 2}SO{sub 4} as catalyst. The purpose of this paper is to evaluate the influence upon the liquefaction yield of the three operating variables, the maximal temperature (150-280 deg C), the reaction time at maximal temperature (20-60 min) and the amount of added H{sub 2}SO{sub 4} (0-1.5% on dry wood). The individual effects, as well as the interactions between operating variables, are investigated by using an experimental design methodology. From a Pareto chart, it appears that the most significant effects are clearly those of the maximum temperature and the interaction between acidity and temperature. Such effects can be graphically verified through response surfaces and contour line plots. From a regression analysis, the conversion rate of wood into liquid is simply expressed as a function of the operating variables by a polynomial containing quadratic terms. A statistical model seems particularly appropriate in the case of complex and multi-components, as wood, a kinetic model is nevertheless proposed for the liquefaction of micro-crystalline cellulose. This model accounts for the formation of a carbonaceous solid residue from the liquid product. Such an unwanted phenomenon obviously results in a lower yield in liquid product. (Author)

  10. Conceptual study of hydrogen donor solvent in the NEDOL coal liquefaction process

    Energy Technology Data Exchange (ETDEWEB)

    Kouzu, M.; Onozaki, M.; Oi, S. [Mitsui SRC Co Ltd, Tokyo (Japan)

    2002-03-01

    A 150 ton/day coal liquefaction pilot plant (PP) of the NEDOL process, supported by New Energy and Industrial Technology Development Organization (NEDO), was operated successfully for a total of 269 days at Kashima, Japan. With a great number of data obtained through the operation, the design procedure for the NEDOL process was studied. Middle and heavy oils from the coal employed were recycled as a hydrogen-donor solvent after hydrotreatment over Ni Mo/gamma-Al2O{sub 3} in a trickle bed reactor. The hydrogen donating ability of the solvent was high enough to obtain higher oil yield (50-58 wt%) at the aromaticity of ca. 0.45. Life expectancy of solvent hydrotreatment catalyst, requisite to the hydrotreater design, was estimated under PP operating conditions. In addition, physical properties of the solvent required for process design were determined, and hydrodynamics in the liquefaction bubble column reactors were examined. Taking the obtained hydrodynamics and thermal behavior into consideration, a design procedure of the liquefaction bubble column reactors was establsihed using a process simulator (CARD) validated by the product yields of PP. The simulation including distillation and solvent hydrotreatment showed that the content of heavy oil fraction (b.p. 350 - 538{degree} C) in the solvent was a determinant factor in the design of a large scale plant based on the NEDOL process.

  11. Vacuum behavior and control of a MEMS stage with integrated thermal displacement sensor

    NARCIS (Netherlands)

    Krijnen, B.; Brouwer, Dannis Michel; Abelmann, Leon; Herder, Justus Laurens

    2015-01-01

    We investigate the applicability of a MEMS stage in a vacuum environment. The stage is suspended by a flexure mechanism and is actuated by electrostatic comb-drives. The position of the stage is measured by an integrated sensor based on the conductance of heat through air. The vacuum behavior of the

  12. Simulation and Optimization of an Innovative Dual Mixed Component Refrigerant Cycle (DMRC) for Natural Gas Offshore Liquefaction Plants

    International Nuclear Information System (INIS)

    SHAHBA, L.A.; Fahmy, M.F.M.

    2004-01-01

    Simulation and optimization of an innovative liquefaction process used for the LNG production , namely the Dual Mixed Refrigerant Process (DMRC) has been conducted using the HYSYS simulator .This new process is especially suitable for off shore natural gas liquefaction plants. A numerical optimization technique has been used to determine the optimum conditions for Egyptian natural gas feed source. The investigation of the effect of different compositions of the Mixed refrigerants used was conducted. Meanwhile, the investigation of the influence of the temperature of cooling water used was conducted. The best optimum conditions for the DMRC process were determined .The optimum results achieved for the DMRC process revealed that the DMRC process can be successfully applied as a promising technique for off shore natural gas liquefaction plants

  13. Shear wave velocity investigation of soil liquefaction sites from the Tangshan, China M7.8 earthquake of 1976 using active and passive surface wave methods

    Science.gov (United States)

    Kayen, Robert E; Tao, Xiaxin; Shi, Lijing; Shi, Hailiang

    2008-01-01

    An initial investigation of soil liquefaction sites from the July, 28 1976 Tangshan M7.8 earthquake was conducted between 1976 and 1978 by the National Ministry of Railways, China. These data are the basis of the ‘Chinese Method’ for assessment of liquefaction potential of silty-sand deposits, and are an important component of the worldwide data set for modern probabilistic methods for assessment of soil liquefaction using Bayesian updating and system reliability tools. We revisited 26 sites identified in the maps and published 198 report of the Ministry of Railways in order to investigate these locations with a suite of active- and passive-array surface wave methods. These sites are clustered along the north coast of the Bo Hai Sea in three areas: Lutai, Tianjin; Tangshan City and outlying village, Hebei; and Luannan county, Hebei. First, we gathered and evaluated the Rayleigh wave dispersion characteristics of the ground by comparing dispersion curves from the active source harmonic wave-spectral analysis of surface waves (SASW) method and the passive array Spatial Auto-Correlation method (SPAC). The dispersive properties of the liquefied ground as measured by these two methods were found to be almost identical. These tests were hybridized and the data sets merged in order to invert of shear wave velocities for analysis of liquefaction potential using a probabilistic framework. The data from high-values of seismic intensity near Tangshan city to low-intensities distant of the event in Luannan County segregate out into clusters of liquefied and non liquefied points clearly separated by liquefaction boundary curves developed from a large global data set of 310 sites

  14. A novel conceptual design of parallel nitrogen expansion liquefaction process for small-scale LNG (liquefied natural gas) plant in skid-mount packages

    International Nuclear Information System (INIS)

    He, Tianbiao; Ju, Yonglin

    2014-01-01

    The utilization of unconventional natural gas is still a great challenge for China due to its distribution locations and small reserves. Thus, liquefying the unconventional natural gas by using small-scale LNG plant in skid-mount packages is a good choice with great economic benefits. A novel conceptual design of parallel nitrogen expansion liquefaction process for small-scale plant in skid-mount packages has been proposed. It first designs a process configuration. Then, thermodynamic analysis of the process is conducted. Next, an optimization model with genetic algorithm method is developed to optimize the process. Finally, the flexibilities of the process are tested by two different feed gases. In conclusion, the proposed parallel nitrogen expansion liquefaction process can be used in small-scale LNG plant in skid-mount packages with high exergy efficiency and great economic benefits. - Highlights: • A novel design of parallel nitrogen expansion liquefaction process is proposed. • Genetic algorithm is applied to optimize the novel process. • The unit energy consumption of optimized process is 0.5163 kWh/Nm 3 . • The exergy efficiency of the optimized case is 0.3683. • The novel process has a good flexibility for different feed gas conditions

  15. Air liquefaction and enrichment system propulsion in reusable launch vehicles

    Science.gov (United States)

    Bond, W. H.; Yi, A. C.

    1994-07-01

    A concept is shown for a fully reusable, Earth-to-orbit launch vehicle with horizontal takeoff and landing, employing an air-turborocket for low speed and a rocket for high-speed acceleration, both using liquid hydrogen for fuel. The turborocket employs a modified liquid air cycle to supply the oxidizer. The rocket uses 90% pure liquid oxygen as its oxidizer that is collected from the atmosphere, separated, and stored during operation of the turborocket from about Mach 2 to 5 or 6. The takeoff weight and the thrust required at takeoff are markedly reduced by collecting the rocket oxidizer in-flight. This article shows an approach and the corresponding technology needs for using air liquefaction and enrichment system propulsion in a single-stage-to-orbit (SSTO) vehicle. Reducing the trajectory altitude at the end of collection reduces the wing area and increases payload. The use of state-of-the-art materials, such as graphite polyimide, in a direct substitution for aluminum or aluminum-lithium alloy, is critical to meet the structure weight objective for SSTO. Configurations that utilize 'waverider' aerodynamics show great promise to reduce the vehicle weight.

  16. Producing Lignin-Based Polyols through Microwave-Assisted Liquefaction for Rigid Polyurethane Foam Production

    Directory of Open Access Journals (Sweden)

    Bai-Liang Xue

    2015-02-01

    Full Text Available Lignin-based polyols were synthesized through microwave-assisted liquefaction under different microwave heating times (5–30 min. The liquefaction reactions were carried out using polyethylene glycol (PEG-400/glycerol as liquefying solvents and 97 wt% sulfur acid as a catalyst at 140 °C. The polyols obtained were analyzed for their yield, composition and structural characteristics using gel permeation chromatography (GPC, Fourier transform infrared (FT-IR and nuclear magnetic resonance (NMR spectra. FT-IR and NMR spectra showed that the liquefying solvents reacted with the phenol hydroxyl groups of the lignin in the liquefied product. With increasing microwave heating time, the viscosity of polyols was slightly increased and their corresponding molecular weight (MW was gradually reduced. The optimal condition at the microwave heating time (5 min ensured a high liquefaction yield (97.47% and polyol with a suitable hydroxyl number (8.628 mmol/g. Polyurethane (PU foams were prepared by polyols and methylene diphenylene diisocyanate (MDI using the one-shot method. With the isocyanate/hydroxyl group ([NCO]/[OH] ratio increasing from 0.6 to 1.0, their mechanical properties were gradually increased. This study provided some insight into the microwave-assisted liquefied lignin polyols for the production of rigid PU foam.

  17. Process for the liquefaction of solid carbonaceous materials wherein nitrogen is separated from hydrogen via ammonia synthesis

    Science.gov (United States)

    Stetka, Steven S.; Nazario, Francisco N.

    1982-01-01

    In a process for the liquefaction of solid carbonaceous materials wherein bottoms residues are upgraded with a process wherein air is employed, the improvement wherein nitrogen buildup in the system is avoided by ammonia synthesis. In a preferred embodiment hydrogen from other portions of the liquefaction process will be combined with hydrogen produced as a result of the bottoms upgrading to increase the H.sub.2 :N.sub.2 ratio in the ammonia reactor.

  18. A characterization and evaluation of coal liquefaction process streams. Quarterly technical progress report, July 1--September 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, G.A.; Brandes, S.D.; Winschel, R.A.; Burke, F.P.

    1995-12-01

    The objectives of this project are to support the DOE direct coal liquefaction process development program and to improve the useful application of analytical chemistry to direct coal liquefaction process development. Independent analyses by well-established methods will be obtained of samples produced in direct coal liquefaction processes under evaluation by DOE. Additionally, analytical instruments and techniques which are currently underutilized for the purpose of examining coal-derived samples will be evaluated. The data obtained from this study will be used to help guide current process development and to develop an improved data base on coal and coal liquids properties. A sample bank will be established and maintained for use in this project and will be available for use by other researchers. The reactivity of the non-distillable resids toward hydrocracking at liquefaction conditions (i.e., resid reactivity) will be examined. From the literature and data experimentally obtained, a mathematical kinetic model of resid conversion will be constructed. It is anticipated that such a model will provide insights useful for improving process performance and thus the economics of direct coal liquefaction. Some of the contract activities for this quarter are: We completed many of the analyses on the 81 samples received from HTI bench-scale run CMSL-9, in which coal, coal/mixed plastics, and coal/high density polyethylene were fed; Liquid chromatographic separations of the 15 samples in the University of Delaware sample set were completed; and WRI completed CP/MAS {sup 13}C-NMR analyses on the Delaware sample set.

  19. Evaluation of performance of analytical and numerical methods to account for liquefaction effects on the seismic response of anchored quay walls

    NARCIS (Netherlands)

    van Elsäcker, W.A.; Besseling, F.; Lengkeek, H.J.; Brinkgreve, R.B.J.; de Gijt, J.G.; Jonkman, S.N.

    2017-01-01

    Liquefaction induced by earthquakes has shown to have potential devastating influence on seismic performance of anchored quay walls. Therefore, measures to mitigate liquefaction are commonly part of the design of quay walls in
    seismically active regions. Such mitigation measures are costly.

  20. Report on the FY 1998 results of the New Sunshine Project (B version). Data attached 2. Development of coal liquefaction technology (Development of base technology of liquefaction (Project on internationalization of coal liquefaction technology)); 1998 nendo sekitan ekika gijutsu kaihatsu seika hokokusho (B ban). Ekika kiban gijutsu no kaihatsu (sekitan ekika gijutsu no kokusaika jigyo (fuzoku shiryo 2))

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    As a part of the project for internationalization of coal liquefaction technology, this paper reported on the potential survey for location of Indonesian low grade coal liquefaction (study of applicability of the improved BCL process and survey of hydrogen production technology using coal gasification). The survey was conducted of a locational possibility of a coal liquefaction commercial plant to be located at mine site in South Sumatra for Banko coal raw material. The improved BCL process was applied in which the results of the study by NBCL Takasago Research Institute were reflected. Further, the hydrogen production was studied by gasification of Banko coal, and the comparison was made with the conventional natural gas reforming method. As a result of the study using information/knowledge obtained during the conceptual design of Australian brown coal, the construction cost of commercial scale liquefaction plant with the Banko coal processing amount of 30,000 tons/day became 549.8 billion yen in the case of using natural gas as raw material for hydrogen production. This construction cost is the lowest as compared with 601.7 billion yen in the demonstrative BCL process and with 577.1 billion yen in the advanced BCL process. This is a process making use of features of Banko coal. The process for hydrogen production by the steam reforming method using natural gas has an advantage of increasing the production amount of coal-derived liquid the most of the three other methods. (NEDO)

  1. Report on the FY 1998 results of the New Sunshine Project (B version). Data attached 1. Development of coal liquefaction technology (Development of base technology of liquefaction (Project on internationalization of coal liquefaction technology)); 1998 nendo sekitan ekika gijutsu kaihatsu seika hokokusho (B ban). Ekika kiban gijutsu no kaihatsu (sekitan ekika gijutsu no kokusaika jigyo (fuzoku shiryo-1))

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    As a part of the project for internationalization of coal liquefaction technology, this paper reported on the potential survey for location of Indonesian low grade coal liquefaction (study of applicability of the improved BCL process and survey of hydrogen production technology using coal gasification). The survey was conducted of a locational possibility of a coal liquefaction commercial plant to be located at mine site in South Sumatra for Banko coal raw material. The improved BCL process was applied in which the results of the study by NBCL Takasago Research Institute were reflected. Further, the hydrogen production was studied by gasification of Banko coal, and the comparison was made with the conventional natural gas reforming method. As a result of the study using information/knowledge obtained during the conceptual design of Australian brown coal, the construction cost of commercial scale liquefaction plant with the Banko coal processing amount of 30,000 tons/day became 549.8 billion yen in the case of using natural gas as raw material for hydrogen production. This construction cost is the lowest as compared with 601.7 billion yen in the demonstrative BCL process and with 577.1 billion yen in the advanced BCL process. This is a process making use of features of Banko coal. The process for hydrogen production by the steam reforming method using natural gas has an advantage of increasing the production amount of coal-derived liquid the most of the three other methods. (NEDO)

  2. Two-Stage Multiobjective Optimization for Emergency Supplies Allocation Problem under Integrated Uncertainty

    Directory of Open Access Journals (Sweden)

    Xuejie Bai

    2016-01-01

    Full Text Available This paper proposes a new two-stage optimization method for emergency supplies allocation problem with multisupplier, multiaffected area, multirelief, and multivehicle. The triplet of supply, demand, and the availability of path is unknown prior to the extraordinary event and is descriptive with fuzzy random variable. Considering the fairness, timeliness, and economical efficiency, a multiobjective expected value model is built for facility location, vehicle routing, and supply allocation decisions. The goals of proposed model aim to minimize the proportion of demand nonsatisfied and response time of emergency reliefs and the total cost of the whole process. When the demand and the availability of path are discrete, the expected values in the objective functions are converted into their equivalent forms. When the supply amount is continuous, the equilibrium chance in the constraint is transformed to its equivalent one. To overcome the computational difficulty caused by multiple objectives, a goal programming model is formulated to obtain a compromise solution. Finally, an example is presented to illustrate the validity of the proposed model and the effectiveness of the solution method.

  3. Conversion of Low-Rank Wyoming Coals into Gasoline by Direct Liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Polyakov, Oleg

    2013-12-31

    Under the cooperative agreement program of DOE and funding from Wyoming State’s Clean Coal Task Force, Western Research Institute and Thermosolv LLC studied the direct conversion of Wyoming coals and coal-lignin mixed feeds into liquid fuels in conditions highly relevant to practice. During the Phase I, catalytic direct liquefaction of sub-bituminous Wyoming coals was investigated. The process conditions and catalysts were identified that lead to a significant increase of desirable oil fraction in the products. The Phase II work focused on systematic study of solvothermal depolymerization (STD) and direct liquefaction (DCL) of carbonaceous feedstocks. The effect of the reaction conditions (the nature of solvent, solvent/lignin ratio, temperature, pressure, heating rate, and residence time) on STD was investigated. The effect of a number of various additives (including lignin, model lignin compounds, lignin-derivable chemicals, and inorganic radical initiators), solvents, and catalysts on DCL has been studied. Although a significant progress has been achieved in developing solvothermal depolymerization, the side reactions – formation of considerable amounts of char and gaseous products – as well as other drawbacks do not render aqueous media as the most appropriate choice for commercial implementation of STD for processing coals and lignins. The trends and effects discovered in DCL point at the specific features of liquefaction mechanism that are currently underutilized yet could be exploited to intensify the process. A judicious choice of catalysts, solvents, and additives might enable practical and economically efficient direct conversion of Wyoming coals into liquid fuels.

  4. Study of pseudo liquefaction of granular material in a rising stream of two-phased foam

    Energy Technology Data Exchange (ETDEWEB)

    Guliev, B B; Mekhtiev, K G

    1970-01-01

    An experimental study was conducted in the laboratory to determine the capability of foam to move loose sand from the bottom to the top of a glass column. The sand used varied in diameter from 1.6 to 10.2 mm. The glass tubes were about 190 cm high and varied in diameter from 3 to 7.6 cm. Foam was produced by mixing air and a solution of surfactant PO-1. Foam density was maintained at 0.1 g/cu cm. In most experiments, foam entered the bottom of the tube and carried the sand as a plug or piston to the top of the tube and out. This happened at slow and fast foam velocities. The data indicated that pseudo liquefaction of sand grains by foam does not occur and that foam should be very effective in removal of sand plugs from wells. Several field tests with foam were successful in removal of sand plugs. Foam was shown to be more effective than water for this purpose.

  5. Numerical simulation of two-dimensional late-stage coarsening for nucleation and growth

    International Nuclear Information System (INIS)

    Akaiwa, N.; Meiron, D.I.

    1995-01-01

    Numerical simulations of two-dimensional late-stage coarsening for nucleation and growth or Ostwald ripening are performed at area fractions 0.05 to 0.4 using the monopole and dipole approximations of a boundary integral formulation for the steady state diffusion equation. The simulations are performed using two different initial spatial distributions. One is a random spatial distribution, and the other is a random spatial distribution with depletion zones around the particles. We characterize the spatial correlations of particles by the radial distribution function, the pair correlation functions, and the structure function. Although the initial spatial correlations are different, we find time-independent scaled correlation functions in the late stage of coarsening. An important feature of the late-stage spatial correlations is that depletion zones exist around particles. A log-log plot of the structure function shows that the slope at small wave numbers is close to 4 and is -3 at very large wave numbers for all area fractions. At large wave numbers we observe oscillations in the structure function. We also confirm the cubic growth law of the average particle radius. The rate constant of the cubic growth law and the particle size distribution functions are also determined. We find qualitatively good agreement between experiments and the present simulations. In addition, the present results agree well with simulation results using the Cahn-Hilliard equation

  6. Feasibility and comparative studies of thermochemical liquefaction of Camellia oleifera cake in different supercritical organic solvents for producing bio-oil

    International Nuclear Information System (INIS)

    Chen, Hongmei; Zhai, Yunbo; Xu, Bibo; Xiang, Bobin; Zhu, Lu; Li, Ping; Liu, Xiaoting; Li, Caiting; Zeng, Guangming

    2015-01-01

    Highlights: • Thermochemical liquefaction of COC was a prominent process for producing bio-oil. • Type of solvent affected the yield and composition of bio-oil considerably. • Liquefaction of COC in SCEL at 300 °C was preferred for producing bio-oil. - Abstract: Thermochemical liquefaction of Camellia oleifera cake (COC) for producing bio-oil was conducted in supercritical methanol (SCML), ethanol (SCEL) and acetone (SCAL), respectively. GC–MS, elemental analysis and ICP-OES were used to characterize properties of bio-oil. Results showed that thermochemical liquefaction of COC was a prominent process for generating bio-oil. Increase of temperature was beneficial to the increase of bio-oil yield, and yield of bio-oil followed the sequence of SCAL > SCEL > SCML. In spite of the highest bio-oil yield, the lowest calorific value and highest contents of Zn, Pb, Cd, Ni, Fe, Mn, and Cr were found in bio-oil from SCAL. Though SCML has very similar bio-oil composition and calorific value with SCEL, higher bio-oil yield and lower contents of heavy metals could be obtained with SCEL, especially in bio-oil from SCEL at 300 °C. Moreover, the origin of ethanol could make the bio-oil product totally renewable. Therefore, liquefaction of COC in SCEL at 300 °C could have great potential in generating bio-oil

  7. Shear wave velocity-based evaluation and design of stone column improved ground for liquefaction mitigation

    Science.gov (United States)

    Zhou, Yanguo; Sun, Zhengbo; Chen, Jie; Chen, Yunmin; Chen, Renpeng

    2017-04-01

    The evaluation and design of stone column improvement ground for liquefaction mitigation is a challenging issue for the state of practice. In this paper, a shear wave velocity-based approach is proposed based on the well-defined correlations of liquefaction resistance (CRR)-shear wave velocity ( V s)-void ratio ( e) of sandy soils, and the values of parameters in this approach are recommended for preliminary design purpose when site specific values are not available. The detailed procedures of pre- and post-improvement liquefaction evaluations and stone column design are given. According to this approach, the required level of ground improvement will be met once the target V s of soil is raised high enough (i.e., no less than the critical velocity) to resist the given earthquake loading according to the CRR- V s relationship, and then this requirement is transferred to the control of target void ratio (i.e., the critical e) according to the V s- e relationship. As this approach relies on the densification of the surrounding soil instead of the whole improved ground and is conservative by nature, specific considerations of the densification mechanism and effect are given, and the effects of drainage and reinforcement of stone columns are also discussed. A case study of a thermal power plant in Indonesia is introduced, where the effectiveness of stone column improved ground was evaluated by the proposed V s-based method and compared with the SPT-based evaluation. This improved ground performed well and experienced no liquefaction during subsequent strong earthquakes.

  8. A Dual-Stage Two-Phase Model of Selective Attention

    Science.gov (United States)

    Hubner, Ronald; Steinhauser, Marco; Lehle, Carola

    2010-01-01

    The dual-stage two-phase (DSTP) model is introduced as a formal and general model of selective attention that includes both an early and a late stage of stimulus selection. Whereas at the early stage information is selected by perceptual filters whose selectivity is relatively limited, at the late stage stimuli are selected more efficiently on a…

  9. [Surgical treatment for incisions fat colliquation or infections at early stage after operation of lumbar disc herniation].

    Science.gov (United States)

    Guan, Ting-Jin; Zheng, Liang-Guo; Sun, Peng; Li, Xing-Xue

    2014-05-01

    To explore the reason, key diagnosic point and therapeutic method of the incisions fat colliquation or infections at early stage after operation of lumbar disc herniation. From July 2007 to May 2012, clinical data of 11 patients with incision fat liquefaction or early infection after lumbar discectomy were retrospectively analyzed. There were 5 males and 6 females with an average age of 43.1 years, and the mean time of incisions fat colliquation or infection was 5 days and a half after operation. The main clinical features included local wound pain aggravating, fervescence, fresh seepage in the wound, and blood inflammatory index increased, etc. The wound could heal at the first treatment stage or not was an evaluation standard of curative effect. All patients were followed up with an average period of 21 months. The wounds of 10 cases healed at the first stage without recurrence and complications. In 1 case infected by staphylococcus aureus, distal part of the wound present local red, swelling and with wave motion at 2 months after operation, staphylococcus aureus infection was confirmed after puncture and bacterial culture, and 1 thrum was found after local incision. The wound healed after change dressings for 1 week, without recurrence after followed up for 13 months. Preventing the risk factors before operation, minimizing invasive technique during operation reasonable antibiotics application for the lumbar operation reguiring placement objects, and correctly handling with wound after operation could prevent and reduce the incidence of incisions fat liquefaction or infection after operation of lumbar disc herniation. For incision fat liquefaction or infection, early diagnosis, debridement, VSD negative pressure irrigation and drainage, to choosing sensitive antibiotics according to the results of drug sensitivity, may contribute to wound early healing and decrease complication.

  10. Advanced liquefaction using coal swelling and catalyst dispersion techniques. Volume 2, appendices. Final technical report, October 1, 1991--September 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, C.W. [Auburn Univ., AL (United States); Chander, S. [Pennsylvania State Univ., College Park, PA (United States); Gutterman, C.

    1995-04-01

    Liquefaction experiments were undertaken using subbituminous Black Thunder mine coal to observe the effects of aqueous SO{sub 2} coal beneficiation and the introduction of various coal swelling solvents and catalyst precursors. Aqueous SO{sub 2} beneficiation of Black Thunder coal removed alkali metals and alkaline earth metals, increased the sulfur content and increased the catalytic liquefaction conversion to THF solubles compared to untreated Black Thunder coal. The liquefaction solvent had varying effects on coal conversion, depending upon the type of solvent added. The hydrogen donor solvent, dihydroanthracene, was most effective, while a coal-derived Wilsonville solvent promoted more coal conversion than did relatively inert 1-methylnaphthalene. Swelling of coal with hydrogen bonding solvents tetrahydrofuran (THF), isopropanol, and methanol, prior to reaction resulted in increased noncatalytic conversion of both untreated and SO{sub 2} treated Black Thunder coals, while dimethylsulfoxide (DMSO), which was absorbed more into the coal than any other swelling solvent, was detrimental to coal conversion. Swelling of SO{sub 2} treated coal before liquefaction resulted in the highest coal conversions; however, the untreated coal showed the most improvements in catalytic reactions when swelled in either THF, isopropanol, or methanol prior to liquefaction. The aprotic solvent DMSO was detrimental to coal conversion.

  11. Survey on the trend of coal liquefaction/gasification technologies, broken down by application; Sekitan no ekika gas ka no yotobetsu gijutsu no doko chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-03-01

    To drive forward the development of the above-named technologies efficiently and effectively, it is necessary to clearly define what coal derived products will meet the need of the clientele and to develop coal derived products accordingly. This survey aims to disclose the whole pictures of the oil/gas using areas and enable the study and evaluation of the possibilities of using coal derived products as substitutes in every one of the expected applications. It also aims to clarify product characteristics, use conditions, technical tasks, and problems to accompany actual substitution in the applications where possibilities are high of their serving as substitutes. Chapter 1, explaining the trend of coal liquefaction/gasification technologies, describes projects for the development of coal liquefaction/gasification technologies, trend of the development of coal liquefaction/gasification technologies, and properties of coal liquefaction/gasification products. Chapter 2, explaining the trend of demand for energy for use in the respective applications, analyzes the trend of demands for oil products, gases, and methanol. Chapter 3 summarizes the applications of chemical materials and fuels for studying the use of coal liquefaction/gasification products as substitutes in the respective applications. Chapter 4 collects problems to solve for the enhancement of coal liquefaction/gasification projects. (NEDO)

  12. [Comparison research on two-stage sequencing batch MBR and one-stage MBR].

    Science.gov (United States)

    Yuan, Xin-Yan; Shen, Heng-Gen; Sun, Lei; Wang, Lin; Li, Shi-Feng

    2011-01-01

    Aiming at resolving problems in MBR operation, like low nitrogen and phosphorous removal efficiency, severe membrane fouling and etc, comparison research on two-stage sequencing batch MBR (TSBMBR) and one-stage aerobic MBR has been done in this paper. The results indicated that TSBMBR owned advantages of SBR in removing nitrogen and phosphorous, which could make up the deficiency of traditional one-stage aerobic MBR in nitrogen and phosphorous removal. During steady operation period, effluent average NH4(+) -N, TN and TP concentration is 2.83, 12.20, 0.42 mg/L, which could reach domestic scenic environment use. From membrane fouling control point of view, TSBMBR has lower SMP in supernatant, specific trans-membrane flux deduction rate, membrane fouling resistant than one-stage aerobic MBR. The sedimentation and gel layer resistant of TSBMBR was only 6.5% and 33.12% of one-stage aerobic MBR. Besides high efficiency in removing nitrogen and phosphorous, TSBMBR could effectively reduce sedimentation and gel layer pollution on membrane surface. Comparing with one-stage MBR, TSBMBR could operate with higher trans-membrane flux, lower membrane fouling rate and better pollutants removal effects.

  13. The current status of coal liquefaction technologies - Panorama 2008; La liquefaction du charbon: ou en est-on aujourd'hui? - Panorama 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    In 2008, a first coal liquefaction unit to produce motor fuel (20,000 BPSD) will come on-stream in Shenhua, China (in the Ercos region of Inner Mongolia). Other, more ambitious projects have been announced in China for between now and 2020. Since oil production is expected to peak in the medium term, this technology may develop regionally in the next 20 years to cover ever-increasing demand for motor fuel.

  14. New magnetic refrigeration materials for the liquefaction of hydrogen

    International Nuclear Information System (INIS)

    Gschneidner, K.A.; Takeya, H.; Moorman, J.O.; Pecharsky, V.K.; Malik, S.K.; Zimm, C.B.

    1994-01-01

    Five heavy lanthanide ferromagnetic intermetallic compounds were studied as potential magnetic refrigerants for the liquefaction of hydrogen gas. (Dy 0.5 Er 0.5 )Al 2 and TbNi 2 appear to be better refrigerants than GdPd for a Joule-Brayton cycle refrigerator, while (Gd 0.54 Er 0.46 )AlNi seems to be a suitable refrigerant for an Ericsson cycle refrigerator

  15. STUDIES ON SOIL LIQUEFACTION AND SETTLEMENT IN THE URAYASU DISTRICT USING EFFECTIVE STRESS ANALYSES FOR THE 2011 EAST JAPAN GREAT EARTHQUAKE

    Science.gov (United States)

    Fukutake, Kiyoshi; Jang, Jiho

    The 2011 East Japan Great Earthquake caused soil liquefaction over a wide area. In particular, severe soil liquefaction was reported in the northern parts of the reclaimed lands around Tokyo Bay, even though the seismic intensity in this area was only about 5 on the Japan scale with low acceleration. The authors surveyed the residual settlement in the Urayasu district and then conducted effective stress analyses of areas affected and not affected by liquefaction. The analyses compared with the acceleration waves monitored with K-NET Urayasu or ground settlements surveyed. It is based on the acceleration observed on the seismic bedrocks in earthquake engineering in some other districts adjacent to Urayasu. Much of the settlement was due to the long duration of the earthquake, with further settlement resulting from the aftershock. The study shows that the affects of aftershocks need to be monitored, as well as needs for improvement of simplified liquefaction prediction methods using the factor of safety, FL.

  16. The influence of magnetic field strength in ionization stage on ion transport between two stages of a double stage Hall thruster

    International Nuclear Information System (INIS)

    Yu Daren; Song Maojiang; Li Hong; Liu Hui; Han Ke

    2012-01-01

    It is futile for a double stage Hall thruster to design a special ionization stage if the ionized ions cannot enter the acceleration stage. Based on this viewpoint, the ion transport under different magnetic field strengths in the ionization stage is investigated, and the physical mechanisms affecting the ion transport are analyzed in this paper. With a combined experimental and particle-in-cell simulation study, it is found that the ion transport between two stages is chiefly affected by the potential well, the potential barrier, and the potential drop at the bottom of potential well. With the increase of magnetic field strength in the ionization stage, there is larger plasma density caused by larger potential well. Furthermore, the potential barrier near the intermediate electrode declines first and then rises up while the potential drop at the bottom of potential well rises up first and then declines as the magnetic field strength increases in the ionization stage. Consequently, both the ion current entering the acceleration stage and the total ion current ejected from the thruster rise up first and then decline as the magnetic field strength increases in the ionization stage. Therefore, there is an optimal magnetic field strength in the ionization stage to guide the ion transport between two stages.

  17. Role of non-ferrous coal minerals and by-product metallic wastes in coal liquefaction. Technical progress report, March 1, 1981-May 31, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Garg, D.; Givens, E.N.; Schweighardt, F.K.; Curtis, C.W.; Guin, J.A.; Huang, W.J.; Shridharani, K.

    1981-06-01

    This report covers results from both tubing-bomb experiments and continuous PDU runs. The following materials were evaluated in the PDU on Elkhorn No. 2 coal from Floyd County, Kentucky: Molybdic oxides; iron oxide; pyrite; pyrite/iron oxide mixture, and iron sulfate impregnation. A base case liquefaction run was also made for direct comparison. All of the above materials were examined at both 825 and 850/sup 0/F. Tubing-bomb experiments are reported on pyrite, red mud, sodium sulfide and organic compounds of cobalt, nickel, molybdenum, zinc, chromium and lead. Significant conclusions were drawn on the catalysis by different materials. Especially significant was the higher level of activity resulting from impregnation versus particle incorporation of the catalyst in the system. Impregnation of coal decreased the hydrocarbon gases yield and increased oil yield. Hydrogen consumption was significantly reduced by impregnation. Addition of molybdic oxide containing 90% MoO/sub 3/ and 10% silica to coal liquefaction reaction mixture had the following effect: coal conversion increased, oil yield increased by more than a factor of two at both temperatures, hydrogen consumption increased, solvent/oil fraction showed substantial increase in hydrogen content, and molybdenum in the resulting liquefaction residue was apparently transformed into an amorphous material. A more thorough evaluation of completely sulfided molybdenum will be made to see if its activity increases. In the tubing-bomb experiments organic compound of molybdenum showed the highest activity for coal conversion and oil production. Significant synergism was noted between red mud and sodium sulfide in the coal liquefaction reaction.

  18. Numerical Analyses of Earthquake Induced Liquefaction and Deformation Behaviour of an Upstream Tailings Dam

    Directory of Open Access Journals (Sweden)

    Muhammad Auchar Zardari

    2017-01-01

    Full Text Available Much of the seismic activity of northern Sweden consists of micro-earthquakes occurring near postglacial faults. However, larger magnitude earthquakes do occur in Sweden, and earthquake statistics indicate that a magnitude 5 event is likely to occur once every century. This paper presents dynamic analyses of the effects of larger earthquakes on an upstream tailings dam at the Aitik copper mine in northern Sweden. The analyses were performed to evaluate the potential for liquefaction and to assess stability of the dam under two specific earthquakes: a commonly occurring magnitude 3.6 event and a more extreme earthquake of magnitude 5.8. The dynamic analyses were carried out with the finite element program PLAXIS using a recently implemented constitutive model called UBCSAND. The results indicate that the magnitude 5.8 earthquake would likely induce liquefaction in a limited zone located below the ground surface near the embankment dikes. It is interpreted that stability of the dam may not be affected due to the limited extent of the liquefied zone. Both types of earthquakes are predicted to induce tolerable magnitudes of displacements. The results of the postseismic slope stability analysis, performed for a state after a seismic event, suggest that the dam is stable during both the earthquakes.

  19. The use of mixed pyrrhotite/pyrite catalysts for co-liquefaction of coal and waste rubber tires

    Energy Technology Data Exchange (ETDEWEB)

    Dadyburjor, D.B.; Zondlo, J.W.; Sharma, R.K. [West Virginia Univ., Morgantown, WV (United States)] [and others

    1995-12-31

    The overall objective of this research program is to determine the optimum processing conditions for tire/coal co-liquefaction. The catalysts used will be a ferric-sulfide-based materials, as well as promising catalysts from other consortium laboratories. The intent here is to achieve the maximum coal+tire conversion at the mildest conditions of temperature and pressure. Specific objectives include an investigation of the effects of time, temperature, pressure, catalyst and co-solvent on the conversion and product slate of the co-liquefaction. Accomplishments and conclusions are discussed.

  20. Neonatal deep white matter venous infarction and liquefaction: a pseudo-abscess lesion

    International Nuclear Information System (INIS)

    Ruess, Lynne; Rusin, Jerome A.; Dent, Carly M.; Tiarks, Hailey J.; Yoshida, Michelle A.

    2014-01-01

    Deep white matter hemorrhagic venous infarction with subsequent cavitation due to necrosis and liquefaction has been described in neonates and may be associated with infection and meningitis. In our experience, the MRI pattern of these lesions is confused with the pattern seen with cerebral abscesses. The purpose of our study was to characterize the MRI findings of post infarction necrosis and liquefaction after hemorrhagic deep white matter venous infarction in infants and to distinguish these lesions from cerebral abscesses. An institutional review board approved a retrospective review of imaging records to identify all patients with cerebral venous infarction at a children's hospital during a 10-year period. Nine infants had deep white matter hemorrhagic venous infarction with white matter fluid signal cavitary lesions. A diagnosis of cerebral abscess was considered in all. The imaging and laboratory findings in these patients are reviewed and compared to descriptions of abscesses found in the literature. There were six female and three male infants. The mean age at presentation was 20 days (range: 0-90 days), while the corrected age at presentation was less than 30 days for all patients. Seven patients presented with seizures and signs of infection; one infant presented with lethargy and later proved to have protein C deficiency. MRI was performed 0-12 days from presentation in these eight patients. Another patient with known protein C deficiency underwent MRI at 30 days for follow-up of screening US abnormalities. There were a total of 38 deep cerebral white matter fluid signal cavitary lesions: 25 frontal, 9 parietal, 2 temporal, 2 occipital. Larger lesions had dependent debris. All lesions had associated hemorrhage and many lesions had evidence of adjacent small vessel venous thrombosis. Lesions imaged after gadolinium showed peripheral enhancement. Three lesions increased in size on follow-up imaging. Three patients, two with meningitis confirmed via

  1. Neonatal deep white matter venous infarction and liquefaction: a pseudo-abscess lesion

    Energy Technology Data Exchange (ETDEWEB)

    Ruess, Lynne; Rusin, Jerome A. [Nationwide Children' s Hospital, Department of Radiology, Columbus, OH (United States); The Ohio State University College of Medicine and Public Health, Columbus, OH (United States); Dent, Carly M.; Tiarks, Hailey J.; Yoshida, Michelle A. [Nationwide Children' s Hospital, Department of Radiology, Columbus, OH (United States)

    2014-11-15

    Deep white matter hemorrhagic venous infarction with subsequent cavitation due to necrosis and liquefaction has been described in neonates and may be associated with infection and meningitis. In our experience, the MRI pattern of these lesions is confused with the pattern seen with cerebral abscesses. The purpose of our study was to characterize the MRI findings of post infarction necrosis and liquefaction after hemorrhagic deep white matter venous infarction in infants and to distinguish these lesions from cerebral abscesses. An institutional review board approved a retrospective review of imaging records to identify all patients with cerebral venous infarction at a children's hospital during a 10-year period. Nine infants had deep white matter hemorrhagic venous infarction with white matter fluid signal cavitary lesions. A diagnosis of cerebral abscess was considered in all. The imaging and laboratory findings in these patients are reviewed and compared to descriptions of abscesses found in the literature. There were six female and three male infants. The mean age at presentation was 20 days (range: 0-90 days), while the corrected age at presentation was less than 30 days for all patients. Seven patients presented with seizures and signs of infection; one infant presented with lethargy and later proved to have protein C deficiency. MRI was performed 0-12 days from presentation in these eight patients. Another patient with known protein C deficiency underwent MRI at 30 days for follow-up of screening US abnormalities. There were a total of 38 deep cerebral white matter fluid signal cavitary lesions: 25 frontal, 9 parietal, 2 temporal, 2 occipital. Larger lesions had dependent debris. All lesions had associated hemorrhage and many lesions had evidence of adjacent small vessel venous thrombosis. Lesions imaged after gadolinium showed peripheral enhancement. Three lesions increased in size on follow-up imaging. Three patients, two with meningitis confirmed via

  2. Soil Improvement By Jet Grout Method And Geogrid Against Liquefaction: Example Of Samsun-Tekkeköy

    Science.gov (United States)

    Öztürk, Seda; Banu İkizler, S.; Şadoǧlu, Erol; Dadaşbilge, Ozan; Angın, Zekai

    2017-04-01

    Liquefaction that occurs due to cyclic and temporary loads on non-cohesive and water-logged sandy soil during earthquake causes considerable loss of lives and property in Turkey and the world. Turkey is a country of which a major part of territories is under earthquake risk due to its tectonic characteristics. Therefore, necessary precautions should be taken against possible disasters such as earthquakes that cannot be prevented in existing conditions. This study focuses on soil improvement applications for a site, located in the influence area of the North Anatolian Fault Zone that is one of the most active strike-slip fault systems of the world. The site was found to have liquefaction potential as a result of the analyses taking into account seismicity of the region and soil conditions. The investigation site is located in the industrial installations, Tekkeköy district of Samsun province and 8 new fuel tanks will be built in the area. Accordingly, as a result of the drilling works performed on the ground for site investigation, the filling layer between 0,9-1,2 m up the ground surface, the medium-tight and medium sand between 6-8 m after filling layer and then at the bottom, following this, medium tight-dense fine-medium sand layers have been encountered. In the Standard Penetration Tests made in this layer, values within N30=11-Refusal (>50) were obtained. It has been determined that the underground water level varies between 1.4-4 m according to the data obtained from the inspection well. In addition, the natural unit weight of the soil was determined as approximately 18 kN/m3 and the internal friction angle as (φ), 30o. The soil is composed of alluviums and layers of medium dense sand of the Holocene age originating from the sea. When all these conditions are evaluated, detailed risk analyses have been deemed necessary, since they indicate a risk of liquefaction. Liquefaction risk analyses were performed according to Seed and Idriss (1971) method for four

  3. Single-stage Acetabular Revision During Two-stage THA Revision for Infection is Effective in Selected Patients.

    Science.gov (United States)

    Fink, Bernd; Schlumberger, Michael; Oremek, Damian

    2017-08-01

    The treatment of periprosthetic infections of hip arthroplasties typically involves use of either a single- or two-stage (with implantation of a temporary spacer) revision surgery. In patients with severe acetabular bone deficiencies, either already present or after component removal, spacers cannot be safely implanted. In such hips where it is impossible to use spacers and yet a two-stage revision of the prosthetic stem is recommended, we have combined a two-stage revision of the stem with a single revision of the cup. To our knowledge, this approach has not been reported before. (1) What proportion of patients treated with single-stage acetabular reconstruction as part of a two-stage revision for an infected THA remain free from infection at 2 or more years? (2) What are the Harris hip scores after the first stage and at 2 years or more after the definitive reimplantation? Between June 2009 and June 2014, we treated all patients undergoing surgical treatment for an infected THA using a single-stage acetabular revision as part of a two-stage THA exchange if the acetabular defect classification was Paprosky Types 2B, 2C, 3A, 3B, or pelvic discontinuity and a two-stage procedure was preferred for the femur. The procedure included removal of all components, joint débridement, definitive acetabular reconstruction (with a cage to bridge the defect, and a cemented socket), and a temporary cemented femoral component at the first stage; the second stage consisted of repeat joint and femoral débridement and exchange of the femoral component to a cementless device. During the period noted, 35 patients met those definitions and were treated with this approach. No patients were lost to followup before 2 years; mean followup was 42 months (range, 24-84 months). The clinical evaluation was performed with the Harris hip scores and resolution of infection was assessed by the absence of clinical signs of infection and a C-reactive protein level less than 10 mg/L. All

  4. Achievement report for fiscal 1981 on Sunshine Program-assisted project. Development of coal liquefaction plant (Research on total system); 1981 nendo sekitan ekika plant no kaihatsu (total system no kenkyu) seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-03-01

    For a quantitative analysis of a coal liquefaction process and its constituent sub-processes from both engineering and economic viewpoints, research is conducted for the development of a coal liquefaction process simulator. In the development of a liquefaction simulator, surveys and studies are performed relative to a coal liquefaction process, which is the object of this development effort, its system, existing like simulators, computation for the estimation of the physical properties that a liquefaction simulator should be equipped with, liquefaction yield prediction model, unit operation model, etc. Based on the results of these studies, a conceptual system design is drawn, which is the first step toward the programming of a more concrete software program. Also compiled into this book are the contents of advice and guidance provided by the total system committee in the period September 1981-February 1982 on the research for the development of a liquefaction simulator, and reports by researchers who were dispatched to the U.S. etc. for the development of a coal liquefaction simulator. (NEDO)

  5. A Modified Critical State Two-surface Plasticity Model for Sand

    DEFF Research Database (Denmark)

    Bakmar, Christian LeBlanc; Hededal, O.; Ibsen, Lars Bo

    This paper provides background information and documentation for the implementation of a robust plasticity model as a user-subroutine in the commercial finite difference code, FLAC3D by Itasca. The plasticity model presented is equal to the 3 dimensional critical state two-surface plasticity model...... volumetric and stress-strain behaviour under monotonic and cyclic loading and thereby related observations like accumulation of pore pressure, cyclic mobility and cyclic liquefaction. The plasticity model is implemented with an integration scheme based on the general return mapping algorithm. The integration...... scheme faces convergence difficulties, primarily at very low mean effective stresses. The convergence problems are addressed by suitable correction strategies designed to add robustness, stability and efficiency to the integration scheme. An outline of all model parameters is given with suggestions...

  6. A 45 ps time digitizer with a two-phase clock and dual-edge two-stage interpolation in a field programmable gate array device

    Science.gov (United States)

    Szplet, R.; Kalisz, J.; Jachna, Z.

    2009-02-01

    We present a time digitizer having 45 ps resolution, integrated in a field programmable gate array (FPGA) device. The time interval measurement is based on the two-stage interpolation method. A dual-edge two-phase interpolator is driven by the on-chip synthesized 250 MHz clock with precise phase adjustment. An improved dual-edge double synchronizer was developed to control the main counter. The nonlinearity of the digitizer's transfer characteristic is identified and utilized by the dedicated hardware code processor for the on-the-fly correction of the output data. Application of presented ideas has resulted in the measurement uncertainty of the digitizer below 70 ps RMS over the time interval ranging from 0 to 1 s. The use of the two-stage interpolation and a fast FIFO memory has allowed us to obtain the maximum measurement rate of five million measurements per second.

  7. A 45 ps time digitizer with a two-phase clock and dual-edge two-stage interpolation in a field programmable gate array device

    International Nuclear Information System (INIS)

    Szplet, R; Kalisz, J; Jachna, Z

    2009-01-01

    We present a time digitizer having 45 ps resolution, integrated in a field programmable gate array (FPGA) device. The time interval measurement is based on the two-stage interpolation method. A dual-edge two-phase interpolator is driven by the on-chip synthesized 250 MHz clock with precise phase adjustment. An improved dual-edge double synchronizer was developed to control the main counter. The nonlinearity of the digitizer's transfer characteristic is identified and utilized by the dedicated hardware code processor for the on-the-fly correction of the output data. Application of presented ideas has resulted in the measurement uncertainty of the digitizer below 70 ps RMS over the time interval ranging from 0 to 1 s. The use of the two-stage interpolation and a fast FIFO memory has allowed us to obtain the maximum measurement rate of five million measurements per second

  8. Hydrothermal liquefaction pathways for low-nitrogen biocrude from wet algae

    Energy Technology Data Exchange (ETDEWEB)

    Tanzella, Francis [SRI International, Menlo Park, CA (United States); Lim, Jin-Ping [SRI International, Menlo Park, CA (United States)

    2016-12-13

    Our SRI International (SRI) team has developed a new two-step hydrothermal liquefaction (HTL) process to convert wet algal biomass into biocrude oil. The first step in the process (low-temperature HTL or HTL1) yields crude oil but, most importantly, it selectively dissolves nitrogen-containing compounds in the aqueous phase. Once the oil and the aqueous phase are separated, the low-nitrogen soft solids left behind can be taken to the second step (high-temperature HTL or HTL2) for full conversion to biocrude. HTL2 will hence yield low-nitrogen biocrude, which can be hydro-processed to yield transportation fuels. The expected high carbon yield and low nitrogen content can lead to a transportation fuel from algae that avoids two problems common to existing algae-to-fuel processes: (1) poisoning of the hydro-processing catalyst; and (2) inefficient conversion of algae-to-liquid fuels. The process we studied would yield a new route to strategic energy production from domestic sources.

  9. Assessment of stone columns as a mitigation technique of liquefaction-induced effects during Italian earthquakes (May 2012).

    Science.gov (United States)

    Forcellini, Davide; Tarantino, Angelo Marcello

    2014-01-01

    Soil liquefaction has been observed worldwide during recent major earthquakes with induced effects responsible for much of the damage, disruption of function, and considerable replacement expenses for structures. The phenomenon has not been documented in recent time with such damage in Italian context before the recent Emilia-Romagna Earthquake (May 2012). The main lateral spreading and vertical deformations affected the stability of many buildings and impacted social life inducing valuable lessons on liquefaction risk assessment and remediation. This paper aims first of all to reproduce soil response to liquefaction-induced lateral effects and thus to evaluate stone column mitigation technique effectiveness by gradually increasing the extension of remediation, in order to achieve a satisfactory lower level of permanent deformations. The study is based on the use of a FE computational interface able to analyse the earthquake-induced three-dimensional pore pressure generation adopting one of the most credited nonlinear theories in order to assess realistically the displacements connected to lateral spreading.

  10. The current status of coal liquefaction technologies - Panorama 2008

    International Nuclear Information System (INIS)

    2008-01-01

    In 2008, a first coal liquefaction unit to produce motor fuel (20,000 BPSD) will come on-stream in Shenhua, China (in the Ercos region of Inner Mongolia). Other, more ambitious projects have been announced in China for between now and 2020. Since oil production is expected to peak in the medium term, this technology may develop regionally in the next 20 years to cover ever-increasing demand for motor fuel

  11. Non-catalytic transfer hydrogenation in supercritical CO2 for coal liquefaction

    Science.gov (United States)

    Elhussien, Hussien

    This thesis presents the results of the investigation on developing and evaluating a low temperature (coal dissolution in supercritical CO2. The main idea behind the thesis was that one hydrogen atom from water and one hydrogen atom from the hydrogen transfer agent (HTA) were used to hydrogenate the coal. The products of coal dissolution were non-polar and polar while the supercritical CO2, which enhanced the rates of hydrogenation and dissolution of the non-polar molecules and removal from the reaction site, was non-polar. The polar modifier (PM) for CO2 was added to the freed to aid in the dissolution and removal of the polar components. The addition of a phase transfer agent (PTA) allowed a seamless transport of the ions and by-product between the aqueous and organic phases. DDAB, used as the PTA, is an effective phase transfer catalyst and showed enhancement to the coal dissolution process. COAL + DH- +H 2O → COAL.H2 + DHO-- This process has a great feature due to the fact that the chemicals were obtained without requir-ing to first convert coal to CO and H2 units as in indirect coal liquefaction. The experiments were conducted in a unique reactor set up that can be connected through two lines. one line to feed the reactor with supercritical CO 2 and the other connected to gas chromatograph. The use of the supercritical CO2 enhanced the solvent option due to the chemical extraction, in addition to the low environmental impact and energy cost. In this thesis the experiment were conducted at five different temperatures from atmos-pheric to 140°C, 3000 - 6000 psi with five component of feed mixture, namely water, HTA, PTA, coal, and PM in semi batch vessels reactor system with a volume of 100 mL. The results show that the chemicals were obtained without requiring to first convert coal to CO and H2 units as in indirect coal liquefaction. The results show that the conversion was found to be 91.8% at opti-mum feed mixtures values of 3, 1.0 and 5.4 for water: PM

  12. 3D visualization of liquefaction-induced dune collapse in the Navajo Sandstone, Utah, USA

    Science.gov (United States)

    Ford, Colby; Nick, Kevin; Bryant, Gerald

    2015-04-01

    The eolian Navajo Sandstone outcrop on the Canyon Overlook Trail in Zion National Park in Southern Utah is dissected by modern erosion in a way which reveals a great deal of the three-dimensional architecture of a major soft-sediment deformation event. The feature is bounded below by a well-developed interdune complex made up of two superimposed carbonate lenses, above by an irregular truncational surface, and incorporates 3 - 10 m of sandstone over an approximately 2 km area. The material above the deformed interval is undeformed cross-bedded sandstone, with crossbeds downlapping onto the surface of truncation. The stratigraphic confinement of deformation and the irregularity of the upper bounding surface suggests a deformation process which created topography, which was in turn covered by the next upwind dune before it could be eroded flat. The deformed material itself is laterally segmented by a stacked succession of shear surfaces, which all strike approximately perpendicular to the paleo-wind direction and dip at decreasing angles in the down paleo-wind direction. These factors point to the collapse of a major dune into the downwind interdune area, likely initiated by liquefaction in the interdune complex. The foundering of the dune's toe into the liquefied area created a powerful lateral stress field which did not extend significantly into the subsurface. The dune collapse process has been used in the past to describe other soft-sediment deformation features in the Navajo Sandstone, but this site provides a wealth of physical details which were not previously associated with dune collapse. Shear surfaces originate in the interdune deposit as slip between laminae, then the cohesive muds provided support as they were thrust upward to angles of up to 50 degrees. The margins of the site also contain important paleoenvironmental indicators. Dinosaur tracks are exposed both at the extreme upwind and downwind margins of the interdune deposit in and slightly above

  13. Beneficial synergistic effect on bio-oil production from co-liquefaction of sewage sludge and lignocellulosic biomass.

    Science.gov (United States)

    Leng, Lijian; Li, Jun; Yuan, Xingzhong; Li, Jingjing; Han, Pei; Hong, Yuchun; Wei, Feng; Zhou, Wenguang

    2018-03-01

    Co-liquefaction of municipal sewage sludge (MSS) and lignocellulosic biomass such as rice straw or wood sawdust at different mixing ratios and the characterization of the obtained bio-oil and bio-char were investigated. Synergistic effects were found during co-processing of MSS with biomass for production of bio-oil with higher yield and better fuel properties than those from individual feedstock. The co-liquefaction of MSS/rice straw (4/4, wt) increased the bio-oil yield from 22.74% (bio-oil yield from liquefaction of MSS individually) or 23.67% (rice straw) to 32.45%. Comparable increase on bio-oil yield was also observed for MSS/wood sawdust mixtures (2/6, wt). The bio-oils produced from MSS/biomass mixtures were mainly composed of esters and phenols with lower boiling points (degradation temperatures) than those from individual feedstock (identified with higher heavy bio-oil fractions). These synergistic effects were probably resulted from the interactions between the intermittent products of MSS and those of biomass during processing. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Two-stage stochastic programming model for the regional-scale electricity planning under demand uncertainty

    International Nuclear Information System (INIS)

    Huang, Yun-Hsun; Wu, Jung-Hua; Hsu, Yu-Ju

    2016-01-01

    Traditional electricity supply planning models regard the electricity demand as a deterministic parameter and require the total power output to satisfy the aggregate electricity demand. But in today's world, the electric system planners are facing tremendously complex environments full of uncertainties, where electricity demand is a key source of uncertainty. In addition, electricity demand patterns are considerably different for different regions. This paper developed a multi-region optimization model based on two-stage stochastic programming framework to incorporate the demand uncertainty. Furthermore, the decision tree method and Monte Carlo simulation approach are integrated into the model to simplify electricity demands in the form of nodes and determine the values and probabilities. The proposed model was successfully applied to a real case study (i.e. Taiwan's electricity sector) to show its applicability. Detail simulation results were presented and compared with those generated by a deterministic model. Finally, the long-term electricity development roadmap at a regional level could be provided on the basis of our simulation results. - Highlights: • A multi-region, two-stage stochastic programming model has been developed. • The decision tree and Monte Carlo simulation are integrated into the framework. • Taiwan's electricity sector is used to illustrate the applicability of the model. • The results under deterministic and stochastic cases are shown for comparison. • Optimal portfolios of regional generation technologies can be identified.

  15. Analysis of the relationship between the coal properties and their liquefaction characteristics by using the coal data base; Tanshu data base ni yoru tanshitsu to ekika tokusei no kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Kanbayashi, Y.; Okada, K. [Coal Mining Research Center, Tokyo (Japan)

    1996-10-28

    The relationship between coal properties and liquefaction or gasification characteristics was analyzed by using the analysis and test results and liquefaction characteristics in the coal data base. On liquefaction reaction, the close relation between an oil yield and coal constituent composition or a coal rank is well-known. Various multivariable regression analyses were conducted by using 6 factors as variables such as calorific value, volatile component, O/C and H/C atomic ratios, exinite+vitrinite content and vitrinite reflectance, and liquefaction characteristics as variate. On liquefaction characteristics, the oil yield of dehydrated and deashed coals, asphaltene yield, hydrogen consumption, produced water and gas quantities, and oil+asphaltene yield were predicted. The theoretical gasification efficiency of each specimen was calculated to evaluate the liquefaction reaction obtained. As a result, the oil yield increased with H/C atomic ratio, while the theoretical gasification efficiency increased with O/C atomic ratio. 5 figs., 1 tab.

  16. Novel bimetallic dispersed catalysts for temperature-programmed coal liquefaction. Technical progress report, October 1995--December 1995

    Energy Technology Data Exchange (ETDEWEB)

    Song, C.; Cooke, W.S.; Schmidt, E.; Schobert, H.H.

    1996-02-01

    Coal liquefaction involves cleavage of methylene, dimethylene and ether bridges connecting polycyclic aromatic units and the reactions of various oxygen functional groups. Here in this quarterly, we report on the catalytic effects of several molybdenum-, cobalt-, and iron-containing compounds in the reactions of dibenzothiophene (DBT) with hydrogen under conditions related to coal liquefaction. The catalytic effects of several molybdenum-, cobalt-, and iron-containing compounds have been examined in the hydrogenation and hydrodesulfurization reactions of dibenzothiophene (DBT) under conditions related to coal liquefaction. The metal compounds are candidate catalyst precursors for direct coal liquefaction. The reactions were carried out in batch microautoclave reactors at 400{degrees}C for 30 minutes with 6.9 MPa (cold) hydrogen pressure, and tridecane solvent. A metal loading of 0.5 mol% resulted in low conversion and only hydrogenation. Addition of sulfur in 4:1 molar ratio led only to a minor increase in conversion and hydrodesulfurization. The use of a higher boiling solvent (octadecane vs. tridecane) was beneficial in providing increased conversion, hydrodesulfurization, and hydrogenation. An increase in metal compound loading to 36.2 mol% led to a dramatic increase in conversion, hydrodesulfurization, and hydrocracking. Molybdenum hexacarbonyl at 36 mol% loading, with added sulfur at 6:1 ratio and octadecane solvent, gave 100% conversion of dibenzothiophene to other products with 100% hydrodesulfurization. Ammonium tetrathiomolybdate and molybdenum(III) chloride are less active under similar conditions. A cobalt-molybdenum thiocubane complex gave unexpectedly low conversions. Iron and cobalt carbonyls also provided very low conversions, even with added sulfur.

  17. Behavior of catalyst and mineral matter in coal liquefaction; Sekitan ekika hannochu no kobusshitsu to shokubai no kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Iwasaki, K.; Wang, J.; Tomita, A. [Tohoku University, Sendai (Japan). Institute for Chemical Reaction Science

    1996-10-28

    Mineral matter in coals is important in various senses for coal liquefaction. It is possible that the catalytic activity is affected by the interaction between catalyst and mineral matter. Iron-based catalyst forms pyrrhotite in the process of liquefaction, but the interaction between it and mineral matter is not known in detail. In this study, the interaction between mineral matter and catalyst and the selective reaction between them were investigated. Tanito Harum coal was used for this study. This coal contains a slight amount of siderite and jarosite besides pyrite as iron compounds. Liquefaction samples were obtained from the 1 t/d NEDOL process PSU. The solid deposits in the reactor mainly contained pyrrhotite and quartz. A slight amount of kaolinite was observed, and pyrite was little remained. It was found that the catalyst (pyrrhotite) often coexisted with quartz, clay and calcite. 8 figs., 2 tabs.

  18. Development of technology for brown coal liquefaction. Design, construction and operation of pilot plant; development of 50t/d pilot plant

    Energy Technology Data Exchange (ETDEWEB)

    1986-08-01

    As for the development of 50t/d pilot plant for the development of liquefaction plant of Victorian brown coal in Austraria, outline of the contents about the second stage construction following the first stage construction up to this time is reported from the following 4 viewpoints; 1: design of process apparatuses, 2: manufacture of apparatuses, 3: fieldwork of the construction and 4: operation of the first stage facilities. On the first item the outline of detail design made by Japanese and Australian companies is described. On the second item the acceptance of purchasing goods from Japan and Australia and the condition of inspection and quality assurance to specific principal parts are described. On the third item the supplementary construction of the first stage, contents of constructions of the second stage are described. On the fourth item, preparation for operation, target, the whole circumstances and the results of maintenance, especially review of operation technique, training of operators, and occurrence and repair of troubles are described. As other relevant works, envirommental assessment, waste disposal, enviromental monitoring for exhaust gases, drainage and working enviroments, safety measure, educational training and moreover activities for local district people and the state of labor market as the support for execution of the project are described.

  19. Novel bimetallic dispersed catalysts for temperature-programmed coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Chunshan, Song; Kirby, S.; Schmidt, E. [Pennsylvania State Univ., University Park, PA (United States)] [and others

    1995-12-31

    The objective of this project is to explore bimetallic dispersed catalysts for more efficient coal liquefaction. Coal liquefaction involves cleavage of methylene, dimethylene and ether bridges connecting various aromatic units and the reactions of various oxygen functional groups. This paper describes recent results on (1) hydrodeoxygenation of O-containing polycyclic model compounds using novel organometallic catalyst precursors; and (2) activity and selectivity of dispersed Fe catalysts from organometallic and inorganic precursors for hydrocracking of 4-(1-naphthylmethyl) bibenzyl. The results showed that some iron containing catalysts have higher activity in the sulfur-free form, contrary to conventional wisdom. Adding sulfur to Fe precursors with Cp-ligands decreased the activity of the resulting catalyst. This is in distinct contrast to the cases with iron pentacarbonyl and superfine Fe{sub 2}O{sub 3}, where S addition increased their catalytic activity substantially. A positive correlation between sulfur addition and increased activity can be seen, but a reversed trend between Fe cluster size and hydrocracking conversion could be observed, for carbonyl-type Fe precursors. It is apparent that the activity and selectivity of Fe catalysts for NMBB conversion depends strongly on both the type of ligand environment, the oxidation state and the number of intermetal bonds in the molecular precursor.

  20. New method for evaluating liquefaction potential

    Energy Technology Data Exchange (ETDEWEB)

    Arulmoli, K.; Arulanandan, K.; Seed, H.B.

    1985-01-01

    A new method of indexing the grain and aggregate properties of sand using electrical parameters is described. Correlations are established between these parameters and relative density, D /sub r/ , cyclic stress ratio, /tau//sigma'/sub 0/, and K2 /sub max/ . An electrical probe, used to predict these parameters from in-situ electrical measurements, is described. Evaluations are made of D /sub r/ and /tau//sigma/sub 0/, which are compared with values measured independently from controlled laboratory tests. Reasonable agreement is found between predicted and measured values. The potential applicability of the electrical probe in the field is shown by evaluation of liquefaction and nonliquefaction at sites affected by the 1906 San Francisco, Niigata and Tangshan earthquakes.

  1. STUDY OF SOLVENT AND CATALYST INTERACTIONS IN DIRECT COAL LIQUEFACTION; SEMIANNUAL

    International Nuclear Information System (INIS)

    Michael T. Klein

    2000-01-01

    There are several aspects of the Direct Coal Liquefaction process which are not fully understood and which if better understood might lead to improved yields and conversions. Among these questions are the roles of the catalyst and the solvent. While the solvent is known to act by transfer of hydrogen atoms to the free radicals formed by thermal breakdown of the coal in an uncatalyzed system, in the presence of a solid catalyst as is now currently practiced, the yields and conversions are higher than in an uncatalyzed system. The role of the catalyst in this case is not completely understood. DOE has funded many projects to produce ultrafine and more active catalysts in the expectation that better contact between catalyst and coal might result. This approach has met with limited success probably because mass transfer between two solids in a fluid medium i.e. the catalyst and the coal, is very poor. It is to develop an understanding of the role of the catalyst and solvent in Direct Liquefaction that this project was initiated. Specifically it was of interest to know whether direct contact between the coal and the catalyst was important. By separating the solid catalyst in a stainless steel basket permeable to the solvent but not the coal in the liquefaction reactor, it was shown that the catalyst still maintains a catalytic effect on the liquefaction process. There is apparently transfer of hydrogen atoms from the catalyst through the basket wall to the coal via the solvent. Strong hydrogen donor solvents appear to be more effective in this respect than weak hydrogen donors. It therefore appears that intimate contact between catalyst and coal is not a requirement, and that the role of the catalyst may be to restore the hydrogen donor strength to the solvent as the reaction proceeds. A range of solvents of varying hydrogen donor strength was investigated. Because of the extensive use of thermogravimetric analysis in this laboratory in was noted that the peak

  2. Assessment and mitigation of liquefaction; Evaluacion y mitigacion de la licuefaccion

    Energy Technology Data Exchange (ETDEWEB)

    Czelada, J. A.; Melentijevic, S.

    2014-07-01

    The simplified empirical procedure in its original form presented in Youd et al (2001) and some further developments given in Idriss and Boulanger (2006) for evaluating liquefaction resistance of soils is presented in this paper only for the criteria based on standard penetration test (SPT). Methods for estimating the ground improvement techniques by stone columns and dynamics compaction are presented. For stone columns Priebe method (1995) and homogenized method (equivalent parameters) are present. for dynamic compaction methods proposed by Recomendacion Geotecnica para las Obras Maritimas y/o Porturaria - ROM 0.5-05 (2005) and Nashed et al. (2009) are described. These analysis methods for each ground improvement technique are compared in two different case histories showing similar results in each one. (Author)

  3. Final Report on Two-Stage Fast Spectrum Fuel Cycle Options

    International Nuclear Information System (INIS)

    Yang, Won Sik; Lin, C. S.; Hader, J. S.; Park, T. K.; Deng, P.; Yang, G.; Jung, Y. S.; Kim, T. K.; Stauff, N. E.

    2016-01-01

    This report presents the performance characteristics of two ''two-stage'' fast spectrum fuel cycle options proposed to enhance uranium resource utilization and to reduce nuclear waste generation. One is a two-stage fast spectrum fuel cycle option of continuous recycle of plutonium (Pu) in a fast reactor (FR) and subsequent burning of minor actinides (MAs) in an accelerator-driven system (ADS). The first stage is a sodium-cooled FR fuel cycle starting with low-enriched uranium (LEU) fuel; at the equilibrium cycle, the FR is operated using the recovered Pu and natural uranium without supporting LEU. Pu and uranium (U) are co-extracted from the discharged fuel and recycled in the first stage, and the recovered MAs are sent to the second stage. The second stage is a sodium-cooled ADS in which MAs are burned in an inert matrix fuel form. The discharged fuel of ADS is reprocessed, and all the recovered heavy metals (HMs) are recycled into the ADS. The other is a two-stage FR/ADS fuel cycle option with MA targets loaded in the FR. The recovered MAs are not directly sent to ADS, but partially incinerated in the FR in order to reduce the amount of MAs to be sent to the ADS. This is a heterogeneous recycling option of transuranic (TRU) elements

  4. Two-stage electrolysis to enrich tritium in environmental water

    International Nuclear Information System (INIS)

    Shima, Nagayoshi; Muranaka, Takeshi

    2007-01-01

    We present a two-stage electrolyzing procedure to enrich tritium in environmental waters. Tritium is first enriched rapidly through a commercially-available electrolyser with a large 50A current, and then through a newly-designed electrolyser that avoids the memory effect, with a 6A current. Tritium recovery factor obtained by such a two-stage electrolysis was greater than that obtained when using the commercially-available device solely. Water samples collected in 2006 in lakes and along the Pacific coast of Aomori prefecture, Japan, were electrolyzed using the two-stage method. Tritium concentrations in these samples ranged from 0.2 to 0.9 Bq/L and were half or less, that in samples collected at the same sites in 1992. (author)

  5. Method of controlling a distillatory coulumn in a liquefaction and distillation device for radioactive rare gases

    International Nuclear Information System (INIS)

    Kimura, Shigeru; Awata, Yoshihisa.

    1975-01-01

    Object: To automatically and securely perform controlling purity of column bottom liquid, which is most difficult in the liquefaction and distillation device. Structure: In a liquefaction and distillation device for liquefying and separating rare gas krypton in fuel reprocessing gases, a difference in temperature between the column bottom liquid (column top) and the distillation portion is detected so as to maintain temperature in the distillation portion of the distilling column constant, and the vaporization amount of column bottom liquid is varied with the difference in temperature to control purity of the column bottom liquid. (Kamimura, M.)

  6. Report on the bituminous coal liquefaction sub-committee in fiscal 1992; 1992 nendo rekiseitan ekika bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-03-01

    This paper reports the activities of the bituminous coal liquefaction sub-committee in the Sunshine Project in fiscal 1992. With an intention of developing a technology on the process (NEDOL) suitable for liquefaction of wide range of coal types placing sub-bituminous coal at the center, researches were carried out by using a pilot plant, and engineering data purposed for practical application of the technology were acquired. The construction of the pilot plant was launched in fiscal 1991. It is necessary to execute the pilot plant plan steadily in the future, and at the same time, reliably acquire different data by means of supportive researches. Economic performance of the process is also important. The first sub-committee meeting presented the following agenda: the status of constructing the 150-t/d pilot plant, tests and investigations thereon, research works by using a 1-t/d PSU, development of the most suitable coal refining technology, development of a coal pretreatment technology, improvement of the distilled oil distribution, studies on coal liquefaction conditions, and studies on solvent hydrogenating catalysts. The second sub-committee meeting presented the following agenda: the status of constructing the pilot plant, tests and investigations on improving the performance of natural pylite catalyst and circulating solvent, technological investigations on structuring a liquefying reaction data analyzing system, studies using a 1-t/d PSU, development of the most suitable coal refining technology, studies on coal liquefaction conditions, and studies on solvent hydrogenating catalysts. (NEDO)

  7. Two-stage nonrecursive filter/decimator

    International Nuclear Information System (INIS)

    Yoder, J.R.; Richard, B.D.

    1980-08-01

    A two-stage digital filter/decimator has been designed and implemented to reduce the sampling rate associated with the long-term computer storage of certain digital waveforms. This report describes the design selection and implementation process and serves as documentation for the system actually installed. A filter design with finite-impulse response (nonrecursive) was chosen for implementation via direct convolution. A newly-developed system-test statistic validates the system under different computer-operating environments

  8. Predicting the liquefaction phenomena from shear velocity profiling: Empirical approach to 6.3 Mw, May 2006 Yogyakarta earthquake

    Energy Technology Data Exchange (ETDEWEB)

    Hartantyo, Eddy, E-mail: hartantyo@ugm.ac.id [PhD student, Physics Department, FMIPA, UGM. Sekip Utara Yogyakarta 55281 Indonesia (Indonesia); Brotopuspito, Kirbani S.; Sismanto; Waluyo [Geophysics Laboratory, FMIPA, Universitas Gadjah Mada, Sekip Utara Yogyakarta 55281 (Indonesia)

    2015-04-24

    The liquefactions phenomena have been reported after a shocking 6.5Mw earthquake hit Yogyakarta province in the morning at 27 May 2006. Several researchers have reported the damage, casualties, and soil failure due to the quake, including the mapping and analyzing the liquefaction phenomena. Most of them based on SPT test. The study try to draw the liquefaction susceptibility by means the shear velocity profiling using modified Multichannel Analysis of Surface Waves (MASW). This paper is a preliminary report by using only several measured MASW points. The study built 8-channel seismic data logger with 4.5 Hz geophones for this purpose. Several different offsets used to record the high and low frequencies of surface waves. The phase-velocity diagrams were stacked in the frequency domain rather than in time domain, for a clearer and easier dispersion curve picking. All codes are implementing in Matlab. From these procedures, shear velocity profiling was collected beneath each geophone’s spread. By mapping the minimum depth of shallow water table, calculating PGA with soil classification, using empirical formula for saturated soil weight from shear velocity profile, and calculating CRR and CSR at every depth, the liquefaction characteristic can be identify in every layer. From several acquired data, a liquefiable potential at some depth below water table was obtained.

  9. A silicon integrated micro nano-positioning XY-stage for nano-manipulation

    International Nuclear Information System (INIS)

    Sun Lining; Wang Jiachou; Rong Weibin; Li Xinxin; Bao Haifei

    2008-01-01

    An integrated micro XY-stage with a 2 × 2 mm 2 movable table is designed and fabricated for application in nanometer-scale operation and nanometric positioning precision. The device integrates the functions of both actuating and sensing in a monolithic chip and is mainly composed of a silicon-based XY-stage, comb-drive actuator and a displacement sensor, which are developed by using double-sided bulk-micromachining technology. The high-aspect-ratio comb-driven XY-stage is achieved by deep reactive ion etching (DRIE) on both sides of the wafer. The displacement sensor is formed on four vertical sidewall surface piezoresistors with a full Wheatstone bridge circuit, where a novel fabrication process of a vertical sidewall surface piezoresistor is proposed. Comprehensive design and analysis of the comb actuator, the piezoresistive displacement sensor and the XY-stage are given in full detail, and the experimental results verify the design and fabrication of the device. The final realization of the device shows that the sensitivity of the fabricated piezoresistive sensors is better than 1.17 mV µm −1 without amplification, and the linearity is better than 0.814%. Under 28.5 V driving voltage, a ±10 µm single-axis displacement is measured without crosstalk and the resonant frequency is measured at 983 Hz in air

  10. Simulation and experimental study of solar-absorption heat transformer integrating with two-stage high temperature vapor compression heat pump

    Directory of Open Access Journals (Sweden)

    Nattaporn Chaiyat

    2014-11-01

    Full Text Available In this study, simulation and experiment studies of a 10 kW solar H2O–LiBr absorption heat transformer (AHT integrating with a two-stage vapor compression heat pump (VCHP were carried out. The whole system was named as compression/absorption heat transformer (CAHT. The VCHP was used to recover rejected heat at the AHT condenser which was transferred back to the AHT evaporator at a higher temperature. The AHT unit took solar heat from a set of flat-plate solar collectors in parallel connection. R-134a and R-123 were refrigerants in the VCHP cycle. From the simulation, the total cycle coefficient (COP of the solar-CAHT was 0.71 compared with 0.49 of the normal solar-AHT. From the experiment, the total cycle COPs of the solar-CAHT and the solar-AHT were 0.62 and 0.39, respectively. The experimental results were lower than those of the simulated models due to the oversize of the experimental compressor. The annual expense of the solar-CAHT was found to be 5113 USD which was lower than 5418 USD of the solar-AHT. So it could be concluded that the modified unit was beneficial than the normal unit in terms of energy efficiency and economic expense.

  11. Energy production from agricultural residues: High methane yields in pilot-scale two-stage anaerobic digestion

    International Nuclear Information System (INIS)

    Parawira, W.; Read, J.S.; Mattiasson, B.; Bjoernsson, L.

    2008-01-01

    There is a large, unutilised energy potential in agricultural waste fractions. In this pilot-scale study, the efficiency of a simple two-stage anaerobic digestion process was investigated for stabilisation and biomethanation of solid potato waste and sugar beet leaves, both separately and in co-digestion. A good phase separation between hydrolysis/acidification and methanogenesis was achieved, as indicated by the high carbon dioxide production, high volatile fatty acid concentration and low pH in the acidogenic reactors. Digestion of the individual substrates gave gross energy yields of 2.1-3.4 kWh/kg VS in the form of methane. Co-digestion, however, gave up to 60% higher methane yield, indicating that co-digestion resulted in improved methane production due to the positive synergism established in the digestion liquor. The integrity of the methane filters (MFs) was maintained throughout the period of operation, producing biogas with 60-78% methane content. A stable effluent pH showed that the methanogenic reactors had good ability to withstand the variations in load and volatile fatty acid concentrations that occurred in the two-stage process. The results of this pilot-scale study show that the two-stage anaerobic digestion system is suitable for effective conversion of semi-solid agricultural residues as potato waste and sugar beet leaves

  12. On A Two-Stage Supply Chain Model In The Manufacturing Industry ...

    African Journals Online (AJOL)

    We model a two-stage supply chain where the upstream stage (stage 2) always meet demand from the downstream stage (stage 1).Demand is stochastic hence shortages will occasionally occur at stage 2. Stage 2 must fill these shortages by expediting using overtime production and/or backordering. We derive optimal ...

  13. FY 1980 Report on results of Sunshine Project. Research and development of coal liquefaction techniques (Development of direct hydrogenation type liquefaction plant and researches on liquefaction reactions in the presence of iron-based catalyst); 1980 nendo sekitan ekika gijutsu no kenkyu kaihatsu, chokusetsu suiten ekika plant no kaihatsu seika hokokusho. Tetsukei shokubai ni yoru ekika hanno no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    This program is aimed at development of iron-based catalyst suited for direct hydrogenation type coal liquefaction by elucidating the effects of the catalyst on the liquefaction reactions. The iron-based catalyst seems to act as the radical stabilizer rather than the reaction promoter, because the increased quantity of the catalyst and increased H{sub 2} pressure share the common pattern rather than the catalyst enhances the activity, which is associated with increased reaction temperature or residence time. This is more notably observed when the coal species is changed to brown coal. In other words, recombination of the decomposition products by polycondensation is accelerated in the presence of the catalyst in decomposition of brown coal from bituminous coal, with the result that the catalyst effects are more notably observed. Whether this results from difference in age between brown coal and bituminous coal or content of specific types of ashes should be elucidated, because this point is considered to deeply relate to eventual development of the liquefaction reaction system. The FY 1980 program includes the primary screening of different types of iron compounds and tests of some iron-metal-based catalysts. (NEDO)

  14. Two new discrete integrable systems

    International Nuclear Information System (INIS)

    Chen Xiao-Hong; Zhang Hong-Qing

    2013-01-01

    In this paper, we focus on the construction of new (1+1)-dimensional discrete integrable systems according to a subalgebra of loop algebra à 1 . By designing two new (1+1)-dimensional discrete spectral problems, two new discrete integrable systems are obtained, namely, a 2-field lattice hierarchy and a 3-field lattice hierarchy. When deriving the two new discrete integrable systems, we find the generalized relativistic Toda lattice hierarchy and the generalized modified Toda lattice hierarchy. Moreover, we also obtain the Hamiltonian structures of the two lattice hierarchies by means of the discrete trace identity

  15. Treatment of corn ethanol distillery wastewater using two-stage anaerobic digestion.

    Science.gov (United States)

    Ráduly, B; Gyenge, L; Szilveszter, Sz; Kedves, A; Crognale, S

    In this study the mesophilic two-stage anaerobic digestion (AD) of corn bioethanol distillery wastewater is investigated in laboratory-scale reactors. Two-stage AD technology separates the different sub-processes of the AD in two distinct reactors, enabling the use of optimal conditions for the different microbial consortia involved in the different process phases, and thus allowing for higher applicable organic loading rates (OLRs), shorter hydraulic retention times (HRTs) and better conversion rates of the organic matter, as well as higher methane content of the produced biogas. In our experiments the reactors have been operated in semi-continuous phase-separated mode. A specific methane production of 1,092 mL/(L·d) has been reached at an OLR of 6.5 g TCOD/(L·d) (TCOD: total chemical oxygen demand) and a total HRT of 21 days (5.7 days in the first-stage, and 15.3 days in the second-stage reactor). Nonetheless the methane concentration in the second-stage reactor was very high (78.9%); the two-stage AD outperformed the reference single-stage AD (conducted at the same reactor loading rate and retention time) by only a small margin in terms of volumetric methane production rate. This makes questionable whether the higher methane content of the biogas counterbalances the added complexity of the two-stage digestion.

  16. Comparative TEA for Indirect Liquefaction Pathways to Distillate-Range Fuels via Oxygenated Intermediates

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Eric; Snowden-Swan, Lesley J.; Talmadge, Michael; Dutta, Abhijit; Jones, Susanne; Ramasamy, Karthikeyan; Gray, Michael; Dagle, Robert; Padmaperuma, Asanga; Gerber, Mark; Sahir, Asad; Tao, Ling; Zhang, Yanan

    2017-03-03

    This paper presents a comparative techno-economic analysis of five conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with specific focus on pathways utilizing oxygenated intermediates (derived either via thermochemical or biochemical conversion steps). The four emerging pathways of interest are compared with one conventional pathway (Fischer-Tropsch) for the production of the hydrocarbon blendstocks. The processing steps of the four emerging pathways include: biomass-to-syngas via indirect gasification, gas cleanup, conversion of syngas to alcohols/oxygenates, followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation. We show that the emerging pathways via oxygenated intermediates have the potential to be cost competitive with the conventional Fischer-Tropsch process. The evaluated pathways and the benchmark process generally exhibit similar fuel yields and carbon conversion efficiencies. The resulting minimum fuel selling prices are comparable to the benchmark at approximately $3.60 per gallon-gasoline equivalent, with potential for two new pathways to be more economically competitive. Additionally, the coproduct values can play an important role in the economics of the processes with oxygenated intermediates derived via syngas fermentation. Major cost drivers for the integrated processes are tied to achievable fuel yields and conversion efficiency of the intermediate steps, i.e., the production of oxygenates/alcohols from syngas and the conversion of oxygenates/alcohols to hydrocarbon fuels.

  17. Rapid Two-stage Versus One-stage Surgical Repair of Interrupted Aortic Arch with Ventricular Septal Defect in Neonates

    Directory of Open Access Journals (Sweden)

    Meng-Lin Lee

    2008-11-01

    Conclusion: The outcome of rapid two-stage repair is comparable to that of one-stage repair. Rapid two-stage repair has the advantages of significantly shorter cardiopulmonary bypass duration and AXC time, and avoids deep hypothermic circulatory arrest. LVOTO remains an unresolved issue, and postoperative aortic arch restenosis can be dilated effectively by percutaneous balloon angioplasty.

  18. Integrating and Analyzing Psychosocial and Stage Theories To Challenge the Development of the Injured Collegiate Athlete.

    Science.gov (United States)

    Harris, Laura L.

    2003-01-01

    Integrated a psychosocial developmental theory (the Kubler-Ross Stage Theory) and a psychological stage theory (the Ross Stage Theory) and a psychological stage theory (the Chickering and Reisser psychosocial and developmental theory) for challenging injured collegiate student-athletes' personal development. A search of online databases from…

  19. Teaching basic life support with an automated external defibrillator using the two-stage or the four-stage teaching technique.

    Science.gov (United States)

    Bjørnshave, Katrine; Krogh, Lise Q; Hansen, Svend B; Nebsbjerg, Mette A; Thim, Troels; Løfgren, Bo

    2018-02-01

    Laypersons often hesitate to perform basic life support (BLS) and use an automated external defibrillator (AED) because of self-perceived lack of knowledge and skills. Training may reduce the barrier to intervene. Reduced training time and costs may allow training of more laypersons. The aim of this study was to compare BLS/AED skills' acquisition and self-evaluated BLS/AED skills after instructor-led training with a two-stage versus a four-stage teaching technique. Laypersons were randomized to either two-stage or four-stage teaching technique courses. Immediately after training, the participants were tested in a simulated cardiac arrest scenario to assess their BLS/AED skills. Skills were assessed using the European Resuscitation Council BLS/AED assessment form. The primary endpoint was passing the test (17 of 17 skills adequately performed). A prespecified noninferiority margin of 20% was used. The two-stage teaching technique (n=72, pass rate 57%) was noninferior to the four-stage technique (n=70, pass rate 59%), with a difference in pass rates of -2%; 95% confidence interval: -18 to 15%. Neither were there significant differences between the two-stage and four-stage groups in the chest compression rate (114±12 vs. 115±14/min), chest compression depth (47±9 vs. 48±9 mm) and number of sufficient rescue breaths between compression cycles (1.7±0.5 vs. 1.6±0.7). In both groups, all participants believed that their training had improved their skills. Teaching laypersons BLS/AED using the two-stage teaching technique was noninferior to the four-stage teaching technique, although the pass rate was -2% (95% confidence interval: -18 to 15%) lower with the two-stage teaching technique.

  20. Two stages and three components of the postural preparation to action.

    Science.gov (United States)

    Krishnan, Vennila; Aruin, Alexander S; Latash, Mark L

    2011-07-01

    Previous studies of postural preparation to action/perturbation have primarily focused on anticipatory postural adjustments (APAs), the changes in muscle activation levels resulting in the production of net forces and moments of force. We hypothesized that postural preparation to action consists of two stages: (1) Early postural adjustments (EPAs), seen a few hundred ms prior to an expected external perturbation and (2) APAs seen about 100 ms prior to the perturbation. We also hypothesized that each stage consists of three components, anticipatory synergy adjustments seen as changes in covariation of the magnitudes of commands to muscle groups (M-modes), changes in averaged across trials levels of muscle activation, and mechanical effects such as shifts of the center of pressure. Nine healthy participants were subjected to external perturbations created by a swinging pendulum while standing in a semi-squatting posture. Electrical activity of twelve trunk and leg muscles and displacements of the center of pressure were recorded and analyzed. Principal component analysis was used to identify four M-modes within the space of muscle activations using indices of integrated muscle activation. This analysis was performed twice, over two phases, 400-700 ms prior to the perturbation and over 200 ms just prior to the perturbation. Similar robust results were obtained using the data from both phases. An index of a multi-M-mode synergy stabilizing the center of pressure displacement was computed using the framework of the uncontrolled manifold hypothesis. The results showed high synergy indices during quiet stance. Each of the two stages started with a drop in the synergy index followed by a change in the averaged across trials activation levels in postural muscles. There was a very long electromechanical delay during the early postural adjustments and a much shorter delay during the APAs. Overall, the results support our main hypothesis on the two stages and three components

  1. Latent hazard related to a hydrogen liquefaction installation

    International Nuclear Information System (INIS)

    Spoendlin, R.

    1961-01-01

    In this note, the author reports an attempt of analysis of hazards which could be related to a hydrogen liquefaction installation in order to identify the most appropriate safety measures. In order to do so, experiments have been performed on electrostatic charges born by solid crystals in liquid hydrogen, and explosion tests have been performed on a mixture of solid oxygen and liquid hydrogen. Moreover, the author tried to analyse accidents which occurred in this field by performing a survey among scientists working in laboratories in different countries

  2. Subsidence by liquefaction-fluidization in man-made strata around Tokyo bay, Japan: from geological survey on damaged part at the 2011 off the Pacific Coast of Tohoku Earthquake

    Science.gov (United States)

    Kazaoka, O.; Kameyama, S.; Shigeno, K.; Suzuki, Y.; Morisaki, M.; Kagawa, A.; Yoshida, T.; Kimura, M.; Sakai, Y.; Ogura, T.; Kusuda, T.; Furuno, K.

    2015-11-01

    Geological disaster by liquefaction-fluidization happened on southern part of the Quaternary Paleo-Kanto submarine basin at the 2011 Earthquake off the Pacific Coast of Tohoku. Liquefaction-fluidization phenomena occurred mainly in man-made strata over shaking 5+ intensity of Japan Meteorological Agency scale. Many subsided spots, 10-50 m width, 20-100 m length and less than 1 m depth, by liquefaction-fluidization distributed on reclaimed land around northern Tokyo bay. Large amount of sand and groundwater spouted out in the terrible subsided parts. But there are little subsidence and no jetted sand outside the terrible subsided part. Liquefaction-fluidization damaged part at the 1987 earthquake east off Chiba prefecture re-liquefied and fluidized in these parts at the 2011 great earthquake. The damaged area were more wide on the 2011 earthquake than the 1987 quake. Detailed classification maps of subsidence by liquefaction-fluidization on the 2011 grate earthquake were made by fieldwork in Chiba city around Tokyo bay. A mechanism of subsidence by liquefaction-fluidization in man-made strata was solved by geological survey with continuous large box cores on the ACE Liner and large relief peals of the cores at a typical subsided part.

  3. A Characterization and Evaluation of Coal Liquefaction Process Streams

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-10-01

    An updated assessment of the physico-chemical analytical methodology applicable to coal-liquefaction product streams and a review of the literature dealing with the modeling of fossil-fuel resid conversion to product oils are presented in this document. In addition, a summary is provided for the University of Delaware program conducted under this contract to develop an empirical test to determine relative resid reactivity and to construct a computer model to describe resid structure and predict reactivity.

  4. Preliminary maps of Quaternary deposits and liquefaction susceptibility, nine-county San Francisco Bay region, California: a digital database

    Science.gov (United States)

    Knudsen, Keith L.; Sowers, Janet M.; Witter, Robert C.; Wentworth, Carl M.; Helley, Edward J.; Nicholson, Robert S.; Wright, Heather M.; Brown, Katherine H.

    2000-01-01

    This report presents a preliminary map and database of Quaternary deposits and liquefaction susceptibility for the nine-county San Francisco Bay region, together with a digital compendium of ground effects associated with past earthquakes in the region. The report consists of (1) a spatial database of fivedata layers (Quaternary deposits, quadrangle index, and three ground effects layers) and two text layers (a labels and leaders layer for Quaternary deposits and for ground effects), (2) two small-scale colored maps (Quaternary deposits and liquefaction susceptibility), (3) a text describing the Quaternary map, liquefaction interpretation, and the ground effects compendium, and (4) the databse description pamphlet. The nine counties surrounding San Francisco Bay straddle the San Andreas fault system, which exposes the region to serious earthquake hazard (Working Group on California Earthquake Probabilities, 1999). Much of the land adjacent to the Bay and the major rivers and streams is underlain by unconsolidated deposits that are particularly vulnerable to earthquake shaking and liquefaction of water-saturated granular sediment. This new map provides a modern and regionally consistent treatment of Quaternary surficial deposits that builds on the pioneering mapping of Helley and Lajoie (Helley and others, 1979) and such intervening work as Atwater (1982), Helley and others (1994), and Helley and Graymer (1997a and b). Like these earlier studies, the current mapping uses geomorphic expression, pedogenic soils, and inferred depositional environments to define and distinguish the map units. In contrast to the twelve map units of Helley and Lajoie, however, this new map uses a complex stratigraphy of some forty units, which permits a more realistic portrayal of the Quaternary depositional system. The two colored maps provide a regional summary of the new mapping at a scale of 1:275,000, a scale that is sufficient to show the general distribution and relationships of

  5. Final Report on Two-Stage Fast Spectrum Fuel Cycle Options

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Won Sik [Purdue Univ., West Lafayette, IN (United States); Lin, C. S. [Purdue Univ., West Lafayette, IN (United States); Hader, J. S. [Purdue Univ., West Lafayette, IN (United States); Park, T. K. [Purdue Univ., West Lafayette, IN (United States); Deng, P. [Purdue Univ., West Lafayette, IN (United States); Yang, G. [Purdue Univ., West Lafayette, IN (United States); Jung, Y. S. [Purdue Univ., West Lafayette, IN (United States); Kim, T. K. [Argonne National Lab. (ANL), Argonne, IL (United States); Stauff, N. E. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-01-30

    This report presents the performance characteristics of twotwo-stage” fast spectrum fuel cycle options proposed to enhance uranium resource utilization and to reduce nuclear waste generation. One is a two-stage fast spectrum fuel cycle option of continuous recycle of plutonium (Pu) in a fast reactor (FR) and subsequent burning of minor actinides (MAs) in an accelerator-driven system (ADS). The first stage is a sodium-cooled FR fuel cycle starting with low-enriched uranium (LEU) fuel; at the equilibrium cycle, the FR is operated using the recovered Pu and natural uranium without supporting LEU. Pu and uranium (U) are co-extracted from the discharged fuel and recycled in the first stage, and the recovered MAs are sent to the second stage. The second stage is a sodium-cooled ADS in which MAs are burned in an inert matrix fuel form. The discharged fuel of ADS is reprocessed, and all the recovered heavy metals (HMs) are recycled into the ADS. The other is a two-stage FR/ADS fuel cycle option with MA targets loaded in the FR. The recovered MAs are not directly sent to ADS, but partially incinerated in the FR in order to reduce the amount of MAs to be sent to the ADS. This is a heterogeneous recycling option of transuranic (TRU) elements

  6. Runway Operations Planning: A Two-Stage Heuristic Algorithm

    Science.gov (United States)

    Anagnostakis, Ioannis; Clarke, John-Paul

    2003-01-01

    The airport runway is a scarce resource that must be shared by different runway operations (arrivals, departures and runway crossings). Given the possible sequences of runway events, careful Runway Operations Planning (ROP) is required if runway utilization is to be maximized. From the perspective of departures, ROP solutions are aircraft departure schedules developed by optimally allocating runway time for departures given the time required for arrivals and crossings. In addition to the obvious objective of maximizing throughput, other objectives, such as guaranteeing fairness and minimizing environmental impact, can also be incorporated into the ROP solution subject to constraints introduced by Air Traffic Control (ATC) procedures. This paper introduces a two stage heuristic algorithm for solving the Runway Operations Planning (ROP) problem. In the first stage, sequences of departure class slots and runway crossings slots are generated and ranked based on departure runway throughput under stochastic conditions. In the second stage, the departure class slots are populated with specific flights from the pool of available aircraft, by solving an integer program with a Branch & Bound algorithm implementation. Preliminary results from this implementation of the two-stage algorithm on real-world traffic data are presented.

  7. Fiscal 1999 research cooperation project report. Research cooperation on coal liquefaction technology; 1999 nendo sekitan ekika gijutsu ni kansuru kenkyu kyoryoku jigyo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This report summarizes the fiscal 1999 research cooperation project result on coal liquefaction technology. Cooperative FS was made on coal liquefaction technology of Indonesian coal as petroleum substituting energy. To obtain the basic data necessary for the FS, study was made on the applicability of Indonesian natural minerals as catalytic materials. Promising low-cost abundant Soroako Limonite ore showed a high catalytic activity for liquefaction reaction of Banko coal, and an excellent grindability. Improved BCL process including hydrogenation process was promising for production of high-quality coal liquid superior in storage stability with less nitrogen and sulfur contents. Survey was made on the general conditions of Tanjung Enim area including South Banko coal field concerned, and the geological features and coal seam of South Banko coal field which is composed of 3 seams including coal deposits of 6.35 hundred million tons. To study the marketability of coal liquid, survey was made on the current situation of oil, oil product standards, and blendability of coal liquid. Hydrogen for the liquefaction process can be obtained by coal gasification. (NEDO)

  8. Two-stage residual inclusion estimation: addressing endogeneity in health econometric modeling.

    Science.gov (United States)

    Terza, Joseph V; Basu, Anirban; Rathouz, Paul J

    2008-05-01

    The paper focuses on two estimation methods that have been widely used to address endogeneity in empirical research in health economics and health services research-two-stage predictor substitution (2SPS) and two-stage residual inclusion (2SRI). 2SPS is the rote extension (to nonlinear models) of the popular linear two-stage least squares estimator. The 2SRI estimator is similar except that in the second-stage regression, the endogenous variables are not replaced by first-stage predictors. Instead, first-stage residuals are included as additional regressors. In a generic parametric framework, we show that 2SRI is consistent and 2SPS is not. Results from a simulation study and an illustrative example also recommend against 2SPS and favor 2SRI. Our findings are important given that there are many prominent examples of the application of inconsistent 2SPS in the recent literature. This study can be used as a guide by future researchers in health economics who are confronted with endogeneity in their empirical work.

  9. Maximally efficient two-stage screening: Determining intellectual disability in Taiwanese military conscripts.

    Science.gov (United States)

    Chien, Chia-Chang; Huang, Shu-Fen; Lung, For-Wey

    2009-01-27

    The purpose of this study was to apply a two-stage screening method for the large-scale intelligence screening of military conscripts. We collected 99 conscripted soldiers whose educational levels were senior high school level or lower to be the participants. Every participant was required to take the Wisconsin Card Sorting Test (WCST) and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) assessments. Logistic regression analysis showed the conceptual level responses (CLR) index of the WCST was the most significant index for determining intellectual disability (ID; FIQ ≤ 84). We used the receiver operating characteristic curve to determine the optimum cut-off point of CLR. The optimum one cut-off point of CLR was 66; the two cut-off points were 49 and 66. Comparing the two-stage window screening with the two-stage positive screening, the area under the curve and the positive predictive value increased. Moreover, the cost of the two-stage window screening decreased by 59%. The two-stage window screening is more accurate and economical than the two-stage positive screening. Our results provide an example for the use of two-stage screening and the possibility of the WCST to replace WAIS-R in large-scale screenings for ID in the future.

  10. Improve the biodegradability of post-hydrothermal liquefaction wastewater with ozone: conversion of phenols and N-heterocyclic compounds.

    Science.gov (United States)

    Yang, Libin; Si, Buchun; Martins, Marcio Arêdes; Watson, Jamison; Chu, Huaqiang; Zhang, Yuanhui; Tan, Xiaobo; Zhou, Xuefei; Zhang, Yalei

    2017-04-01

    Hydrothermal liquefaction is a promising technology to convert wet biomass into bio-oil. However, post-hydrothermal liquefaction wastewater (PHWW) is also produced during the process. This wastewater contains a high concentration of organic compounds, including phenols and N-heterocyclic compounds which are two main inhibitors for biological treatment. Thus, proper treatment is required. In this work, ozone was used to convert phenols and N-heterocyclic compounds with a dosage range of 0-4.64 mg O 3 /mL PHWW. After ozone treatment, the phenols were fully converted, and acids were produced. However, N-heterocyclic compounds were found to have a low conversion rate (21.7%). The kinetic analysis for the degradation of phenols and N-heterocyclic compounds showed that the substitute played an important role in determining the priority of ozone reactions. The OH moiety in the ring compounds (phenols and pyridinol) may form hydroxyl radical, which lead to an efficient reaction. A substantial improved biodegradability of PHWW was observed after ozone treatment. The ratio of BOD 5 /COD was increased by about 32.36%, and reached a maximum of 0.41. The improved biodegradability of PHWW was justified by the conversion of phenols and N-heterocyclic compounds.

  11. The Dynamic Behavior of a Network of Pipelines and Liquefaction of Soil Caused by the Earthquake Acceleration

    Directory of Open Access Journals (Sweden)

    Alireza Mirza Goltabar Roshan

    2015-09-01

    Full Text Available Risk analysis pipelines in the quake as one of the most vital arteries in the current circumstances in the world is of special importance. in our everyday activities, used to underground structures such as pipes, tunnels, wells and so on for services such as transporting water, transportation, irrigation, drainage, sewage disposal, transporting oil and gas, carrying acid waste, industrial, household and so on. With regard to the huge investments structures, especially buried underground pipes, we need to study these constructs in response to the earthquake, is clearly felt. Pipelines used for transporting gas and other fluids, are widely distributed in all areas. These lines due to passing through the densely populated areas are always buried in the earth. Seismic behavior of these pipes as a result of the interaction between the soil and the pipe is different from the above-ground structures. The manner of modelling of the effects of soil liquefaction on the pipes in this thesis is that two shear springs and a normal spring is defined between soil and the pipe that in liquefaction mode minimize the friction shear strength.

  12. [Transformation Regularity of Nitrogen in Aqueous Product Derived from Hydrothermal Liquefaction of Sewage Sludge in Subcritical Water].

    Science.gov (United States)

    Sun, Yan-qing; Sun, Zhen; Zhang, Jing-lai

    2015-06-01

    Hydrothermal liquefaction in subcritical water is a potential way to treat sewage sludge as a resource rather than a waste. This study focused on the transformation regularity of nitrogen in aqueous product which was derived from hydrothermal liquefaction of sewage sludge under different operating conditions. Results showed, within the studied temperature scope and time span, the concentration of total nitrogen (TN) fluctuated in the range of 2867.62 mg x L(-1) to 4171.30 mg x L(-1). The two major exiting formation of nitrogen in aqueous product was ammonia nitrogen (NH4+ -N) and organic nitrogen (Org-N). NH4+ -N possessed 54.6%-90.7% of TN, while Org-N possessed 7.4%-44.5%. The concentration of nitrate nitrogen (NO- -N) was far more less than NH4+ -N and Org-N. Temperature had a great influence on the transformation regularity of nitrogen. Both the concentration of TN and Org-N increased accordingly to the increase of reaction temperature. With the reaction time prolonging, the concentration of TN and Org-N increased, while the concentration of NH4+ -N increased first, then became stationary, and then decreased slightly.

  13. The Two-Word Stage: Motivated by Linguistic or Cognitive Constraints?

    Science.gov (United States)

    Berk, Stephanie; Lillo-Martin, Diane

    2012-01-01

    Child development researchers often discuss a "two-word" stage during language acquisition. However, there is still debate over whether the existence of this stage reflects primarily cognitive or linguistic constraints. Analyses of longitudinal data from two Deaf children, Mei and Cal, not exposed to an accessible first language (American Sign…

  14. A two-stage heating scheme for heat assisted magnetic recording

    Science.gov (United States)

    Xiong, Shaomin; Kim, Jeongmin; Wang, Yuan; Zhang, Xiang; Bogy, David

    2014-05-01

    Heat Assisted Magnetic Recording (HAMR) has been proposed to extend the storage areal density beyond 1 Tb/in.2 for the next generation magnetic storage. A near field transducer (NFT) is widely used in HAMR systems to locally heat the magnetic disk during the writing process. However, much of the laser power is absorbed around the NFT, which causes overheating of the NFT and reduces its reliability. In this work, a two-stage heating scheme is proposed to reduce the thermal load by separating the NFT heating process into two individual heating stages from an optical waveguide and a NFT, respectively. As the first stage, the optical waveguide is placed in front of the NFT and delivers part of laser energy directly onto the disk surface to heat it up to a peak temperature somewhat lower than the Curie temperature of the magnetic material. Then, the NFT works as the second heating stage to heat a smaller area inside the waveguide heated area further to reach the Curie point. The energy applied to the NFT in the second heating stage is reduced compared with a typical single stage NFT heating system. With this reduced thermal load to the NFT by the two-stage heating scheme, the lifetime of the NFT can be extended orders longer under the cyclic load condition.

  15. Mechanical integrity of PFHE in LNG liquefaction process

    NARCIS (Netherlands)

    Ligterink, N.E.; Hageraats-Ponomareva, S.V.; Velthuis, J.F.M.

    2012-01-01

    The mechanical integrity of heat exchangers is the result of an interplay of many physical phenomena. A full, albeit simple, model, that covers mixture phase thermodynamics, heat transfer, flow dynamics, and the thermal and pressure stresses has been created. Using this simulation model it is now

  16. Design and analysis of a small-scale natural gas liquefaction process adopting single nitrogen expansion with carbon dioxide pre-cooling

    International Nuclear Information System (INIS)

    Yuan, Zongming; Cui, Mengmeng; Xie, Ying; Li, Chunlin

    2014-01-01

    With the growth of energy consumption and environmental protection concerns, it is of enormous economic and environmental values for the development of stranded gas. As a means for exploitation and transportation of stranded gas to market, a novel small-scale liquefaction process adopting single nitrogen expansion with carbon dioxide pre-cooling is put up with in this paper. Taking unit energy consumption as the target function, Aspen HYSYS is employed to simulate and optimize the process to achieve the liquefaction rate of 0.77 with unit energy consumption of 9.90 kW/kmol/h. Furthermore, the adaptability of this process under different pressure, temperature and compositions of feed gas is studied. Based on the optimization results, the exergy losses of main equipment in the process are evaluated and analyzed in details. With compact device, safety operation, simple capability, this liquefaction process proves to be suitable for the development of small gas reserves, satellite distribution fields of gas or coalbed methane fields. - Highlights: •A novel small-scale liquefaction process used in stranded gas is designed. •The adaptability of this process under different pressure, temperature and compositions of feed gas is studied. •The exergy analysis of main equipment in the process is analyzed

  17. Design and analysis of a small-scale natural gas liquefaction process adopting single nitrogen expansion with carbon dioxide pre-cooling

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Zongming; Cui, Mengmeng; Xie, Ying; Li, Chunlin

    2014-03-01

    With the growth of energy consumption and environmental protection concerns, it is of enormous economic and environmental values for the development of stranded gas. As a means for exploitation and transportation of stranded gas to market, a novel small-scale liquefaction process adopting single nitrogen expansion with carbon dioxide pre-cooling is put up with in this paper. Taking unit energy consumption as the target function, Aspen HYSYS is employed to simulate and optimize the process to achieve the liquefaction rate of 0.77 with unit energy consumption of 9.90 kW/kmol/h. Furthermore, the adaptability of this process under different pressure, temperature and compositions of feed gas is studied. Based on the optimization results, the exergy losses of main equipment in the process are evaluated and analyzed in details. With compact device, safety operation, simple capability, this liquefaction process proves to be suitable for the development of small gas reserves, satellite distribution fields of gas or coalbed methane fields. - Highlights: •A novel small-scale liquefaction process used in stranded gas is designed. •The adaptability of this process under different pressure, temperature and compositions of feed gas is studied. •The exergy analysis of main equipment in the process is analyzed.

  18. Microalgae growth on the aqueous phase from Hydrothermal Liquefaction of the same microalgae

    NARCIS (Netherlands)

    Garcia Alba, Laura;