WorldWideScience

Sample records for catalytic multi-stage liquefaction

  1. 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.

  2. Catalytic coal liquefaction. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Weller, S W

    1981-01-01

    Monolith catalysts of MoO/sub 3/-CoO-Al/sub 2/O/sub 3/ were prepared and tested for coal liquefaction in a stirred autoclave. In general, the monolith catalysts were not as good as particulate catalysts prepared on Corning alumina supports. Measurement of O/sub 2/ chemisorption and BET surface area has been made on a series of Co/Mo/Al/sub 2/O/sub 3/ catalysts obtained from PETC. The catalysts were derived from Cyanamid 1442A and had been tested for coal liquefaction in batch autoclaves and continuous flow units. MoO/sub 3/-Al/sub 2/O/sub 3/ catalysts over the loading range 3.9 to 14.9 wt % MoO/sub 3/ have been studied with respect to BET surface (before and after reduction), O/sub 2/ chemisorption at -78/sup 0/C, redox behavior at 500/sup 0/C, and activity for cyclohexane dehydrogenation at 500/sup 0/C. In connection with the fate of tin catalysts during coal liquefaction, calculations have been made of the relative thermodynamic stability of SnCl/sub 2/, Sn, SnO/sub 2/, and SnS in the presence of H/sub 2/, HCl, H/sub 2/S and H/sub 2/O. Ferrous sulfate dispersed in methylnaphthalene has been shown to be reduced to ferrous sulfide under typical coal hydroliquefaction conditions (1 hour, 450/sup 0/C, 1000 psi initial p/sub H/sub 2//). This suggests that ferrous sulfide may be the common catalytic ingredient when either (a) ferrous sulfate impregnated on powdered coal, or (b) finely divided iron pyrite is used as the catalyst. Old research on impregnated ferrous sulfate, impregnated ferrous halides, and pyrite is consistent with this assumption. Eight Co/Mo/Al/sub 2/O/sub 3/ catalysts from commercial suppliers, along with SnCl/sub 2/, have been studied for the hydrotreating of 1-methylnaphthalene (1-MN) in a stirred autoclave at 450 and 500/sup 0/C.

  3. Multi-stage selective catalytic reduction of NOx in lean burn engine exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Penetrante, B.M.; Hsaio, M.C.; Merritt, B.T.; Vogtlin, G.E. [Lawrence Livermore National Lab., CA (United States)

    1997-12-31

    Many studies suggest that the conversion of NO to NO{sub 2} is an important intermediate step in the selective catalytic reduction (SCR) of NO{sub x} to N{sub 2}. Some effort has been devoted to separating the oxidative and reductive functions of the catalyst in a multi-stage system. This method works fine for systems that require hydrocarbon addition. The hydrocarbon has to be injected between the NO oxidation catalyst and the NO{sub 2} reduction catalyst; otherwise, the first-stage oxidation catalyst will also oxidize the hydrocarbon and decrease its effectiveness as a reductant. The multi-stage catalytic scheme is appropriate for diesel engine exhausts since they contain insufficient hydrocarbons for SCR, and the hydrocarbons can be added at the desired location. For lean-burn gasoline engine exhausts, the hydrocarbons already present in the exhausts will make it necessary to find an oxidation catalyst that can oxidize NO to NO{sub 2} but not oxidize the hydrocarbon. A plasma can also be used to oxidize NO to NO{sub 2}. Plasma oxidation has several advantages over catalytic oxidation. Plasma-assisted catalysis can work well for both diesel engine and lean-burn gasoline engine exhausts. This is because the plasma can oxidize NO in the presence of hydrocarbons without degrading the effectiveness of the hydrocarbon as a reductant for SCR. In the plasma, the hydrocarbon enhances the oxidation of NO, minimizes the electrical energy requirement, and prevents the oxidation of SO{sub 2}. This paper discusses the use of multi-stage systems for selective catalytic reduction of NO{sub x}. The multi-stage catalytic scheme is compared to the plasma-assisted catalytic scheme.

  4. Compressor selection methods for multi-stage re-liquefaction system of liquefied CO2 transport ship for CCS

    International Nuclear Information System (INIS)

    Recently, CCS (carbon dioxide capture and sequestration) has been receiving considerable attention as a possible means of dealing with emissions of CO2, a greenhouse gas. To this end, EOR (enhanced oil recovery) and EGR (enhanced gas recovery) are regarded as being viable options for economically sequestrating large amounts of CO2. A feasible approach would involve capturing CO2 from large-scale CO2 emission sources such as power plants, and then transporting that captured gas to near-depleted oil and gas wells to maintain the reservoir pressure and enhance the oil/gas recovery rate. In the future, CO2 will be transported large distances from emission sources in developed countries to oil/gas producing regions by pipelines or ships. The long-distance ship-based transport of CO2 would require that the gas be compressed or liquefied (LCO2). Furthermore, an LCO2 transport ship would have to be capable of processing boil-off gas while at sea. In this study, the selection method of compressors for re-liquefaction system of dedicated LCO2 transport ship was investigated by computational method. The performance of same compression ratio (SCR) method exhibited low levels of efficiency and reliability as for coefficient of performance (COP) and compressor discharge temperature in terms of oil degradation compared to that of intermediate pressure optimization (IPO). Of these three methods, IPO produced the highest level of performance of all, but could not guarantee compressor reliability as like SCR, too. Intermediate pressure optimization with same discharge temperature (IPODT) method was found to be better in terms of reliability, with a decrease in performance of only 5% relative to that obtained by IPO. Consequently, we recommend the use of the IPODT method for the design of a multi-stage compression system for the re-liquefaction cycle of an LCO2 transport ship. - Highlights: • Compressor selection methods for CO2 re-liquefaction system are compared. • Simulation

  5. 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.

  6. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Song, C.; Huang, L.; Wenzel, K.; Saini, A.K.; Burgess, C.; Hatcher, P.G.; Schobert, H.H.

    1992-12-01

    During this quarterly period progress has been made in the following three subjects related to the effects of low-temperature thermal and catalytic pretreatments on coal structure and reactivity in liquefaction. First, the liquefaction behavior of three bituminous coals with a carbon content ranging from 77% to 85% was evaluated spectroscopically by [sup 13]C NMR and pyrolysis/gas chromatography/mass spectrometry to delineate the structural changes that occur in the coal during liquefaction. Complementary data includes ultimate and proximate analysis, along with optical microscopy for maceral determinations. Even though these are all bituminous coals they exhibit quite different physical and chemical characteristics. The coals vary in rank, ranging from HvC b to HvA b, in petrographic composition, different maceral percentages, and in chemical nature, percent of carbon and of volatiles. It is these variations that govern the products, their distribution, and conversion percentages. Some of the products formed can be traced to a specific maceral group. Second, pyrolysis-GC-MS and FTIR techniques were used to characterize Wyodak coal before and after drying in vacuum and in air and the residues from its thermal and catalytic liquefactions. The analysis of the air-dried coal shows a decrease in the phenolic type structures in the coal network and increase in the carbonyl structures as the oxidative drying proceeds. An enhanced decrease in the carbonyl structure is observed in the liquefaction residues from the raw coal as compared to that of the vacuum dried coal. The analyses of the liquefaction residues of the air-dried coal show an increase in the ether linkages which may have a negative impact on liquefaction. The extent of the solvent adduction also increases during liquefaction with the extent of oxidation of the coal. Finally, the effects of reaction conditions were investigated on conversion of low-rank coals using a Texas subbituminous coal.

  7. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Song, C.; Saini, A.; Huang, L.; Wenzel, K.; Hatcher, P.G.; Schobert, H.H.

    1992-01-01

    Low-temperature catalytic pretreatment is a promising approach to the development of an improved liquefaction process. This work is a fundamental study on effects of pretreatments on coal structure and reactivity in liquefaction. The main objectives of this project are to study the coal structural changes induced by low-temperature catalytic and thermal pretreatments by using spectroscopic techniques; and to clarify the pretreatment-induced changes in reactivity or convertibility of coals in the subsequent liquefaction. This report describes the progress of our work during the first quarterly period. Substantial progress has been made in the spectroscopic characterization of fresh and THF-extracted samples of two subbituminous coals and fresh samples of three bituminous coals using cross-polarization magic angle spinning (CPMAS) solid state {sup 13}C NMR and pyrolysis-GC-MS techniques. CPMAS {sup 13}C NMR and pyrolysis-GC-MS provided important information on carbon distribution/functionality and molecular components/structural units, respectively, for these coal samples. Pyrolysis-GC-MS revealed that there are remarkable structural differences in structural units between the subbituminous coals and the bituminous coals. Furthermore, significant progress has been made in the pretreatments and spectroscopic characterization of catalytically and thermally pretreated as well as physically treated Wyodak subbituminous coal, and temperature-staged and temperature-programmed thermal and catalytic liquefaction of a Montana subbituminous coal.

  8. HRI catalytic two-stage liquefaction (CTSL) process materials: chemical analysis and biological testing

    Energy Technology Data Exchange (ETDEWEB)

    Wright, C.W.; Later, D.W.

    1985-12-01

    This report presents data from the chemical analysis and biological testing of coal liquefaction materials obtained from the Hydrocarbon Research, Incorporated (HRI) catalytic two-stage liquefaction (CTSL) process. Materials from both an experimental run and a 25-day demonstration run were analyzed. Chemical methods of analysis included adsorption column chromatography, high-resolution gas chromatography, gas chromatography/mass spectrometry, low-voltage probe-inlet mass spectrometry, and proton nuclear magnetic resonance spectroscopy. The biological activity was evaluated using the standard microbial mutagenicity assay and an initiation/promotion assay for mouse-skin tumorigenicity. Where applicable, the results obtained from the analyses of the CTSL materials have been compared to those obtained from the integrated and nonintegrated two-stage coal liquefaction processes. 18 refs., 26 figs., 22 tabs.

  9. Hydrothermal processing of fermentation residues in a continuous multistage rig – Operational challenges for liquefaction, salt separation, and catalytic gasification

    International Nuclear Information System (INIS)

    Fermentation residues are a waste stream of biomethane production containing substantial amounts of organic matter, and thus representing a primary energy source which is mostly unused. For the first time this feedstock was tested for catalytic gasification in supercritical water (T ≥ 374 °C, p ≥ 22 MPa) for methane production. The processing steps include hydrothermal liquefaction, salt separation, as well as catalytic gasification over a ruthenium catalyst in supercritical water. In continuous experiments at a feed rate of 1 kg h−1 a partial liquefaction and carbonization of some of the solids was observed. Significant amounts of heavy tars were formed. Around 50% of the feed carbon remained in the rig. Furthermore, a homogeneous coke was formed, presumably originating from condensed tars. The mineralization of sulfur and its separation in the salt separator was insufficient, because most of the sulfur was still organically bound after liquefaction. Desalination was observed at a salt separator set point temperature of 450 °C and 28 MPa; however, some of the salts could not be withdrawn as a concentrated brine. At 430 °C no salt separation took place. Higher temperatures in the salt separator were found to promote tar and coke formation, resulting in conflicting process requirements for efficient biomass liquefaction and desalination. In the salt separator effluent, solid crystals identified as struvite (magnesium ammonium phosphate) were found. This is the first report of struvite formation from a supercritical water biomass conversion process and represents an important finding for producing a fertilizer from the separated salt brine. - Highlights: • Continuous processing of fermentation residues in sub- and supercritical water. • Continuous separation of salt brines at supercritical water conditions. • Struvite crystals (magnesium ammonium phosphate) were recovered from the effluent. • Separation of sulfur from the biomass could not

  10. Preliminary chemical analysis and biological testing of materials from the HRI catalytic two-stage liquefaction (CTSL) process. [Aliphatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Later, D.W.; Wilson, B.W.

    1985-01-01

    Coal-derived materials from experimental runs of Hydrocarbon Research Incorporated's (HRI) catalytic two-stage liquefaction (CTSL) process were chemically characterized and screened for microbial mutagenicity. This process differs from two-stage coal liquefaction processes in that catalyst is used in both stages. Samples from both the first and second stages were class-fractionated by alumina adsorption chromatography. The fractions were analyzed by capillary column gas chromatography; gas chromatography/mass spectrometry; direct probe, low voltage mass spectrometry; and proton nuclear magnetic resonance spectrometry. Mutagenicity assays were performed with the crude and class fractions in Salmonella typhimurium, TA98. Preliminary results of chemical analyses indicate that >80% CTSL materials from both process stages were aliphatic hydrocarbon and polynuclear aromatic hydrocarbon (PAH) compounds. Furthermore, the gross and specific chemical composition of process materials from the first stage were very similar to those of the second stage. In general, the unfractionated materials were only slightly active in the TA98 mutagenicity assay. Like other coal liquefaction materials investigated in this laboratory, the nitrogen-containing polycyclic aromatic compound (N-PAC) class fractions were responsible for the bulk of the mutagenic activity of the crudes. Finally, it was shown that this activity correlated with the presence of amino-PAH. 20 figures, 9 tables.

  11. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction. Technical progress report, August 1992--November 1992

    Energy Technology Data Exchange (ETDEWEB)

    Song, C.; Huang, L.; Wenzel, K.; Saini, A.K.; Burgess, C.; Hatcher, P.G.; Schobert, H.H.

    1992-12-01

    During this quarterly period progress has been made in the following three subjects related to the effects of low-temperature thermal and catalytic pretreatments on coal structure and reactivity in liquefaction. First, the liquefaction behavior of three bituminous coals with a carbon content ranging from 77% to 85% was evaluated spectroscopically by {sup 13}C NMR and pyrolysis/gas chromatography/mass spectrometry to delineate the structural changes that occur in the coal during liquefaction. Complementary data includes ultimate and proximate analysis, along with optical microscopy for maceral determinations. Even though these are all bituminous coals they exhibit quite different physical and chemical characteristics. The coals vary in rank, ranging from HvC b to HvA b, in petrographic composition, different maceral percentages, and in chemical nature, percent of carbon and of volatiles. It is these variations that govern the products, their distribution, and conversion percentages. Some of the products formed can be traced to a specific maceral group. Second, pyrolysis-GC-MS and FTIR techniques were used to characterize Wyodak coal before and after drying in vacuum and in air and the residues from its thermal and catalytic liquefactions. The analysis of the air-dried coal shows a decrease in the phenolic type structures in the coal network and increase in the carbonyl structures as the oxidative drying proceeds. An enhanced decrease in the carbonyl structure is observed in the liquefaction residues from the raw coal as compared to that of the vacuum dried coal. The analyses of the liquefaction residues of the air-dried coal show an increase in the ether linkages which may have a negative impact on liquefaction. The extent of the solvent adduction also increases during liquefaction with the extent of oxidation of the coal. Finally, the effects of reaction conditions were investigated on conversion of low-rank coals using a Texas subbituminous coal.

  12. Multi-stage flash degaser

    Science.gov (United States)

    Rapier, Pascal M.

    1982-01-01

    A multi-stage flash degaser (18) is incorporated in an energy conversion system (10) having a direct-contact, binary-fluid heat exchanger to remove essentially all of the noncondensable gases from geothermal brine ahead of the direct-contact binary-fluid heat exchanger (22) in order that the heat exchanger (22) and a turbine (48) and condenser (32) of the system (10) can operate at optimal efficiency.

  13. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction. Technical progress report, October 1991--December 1991

    Energy Technology Data Exchange (ETDEWEB)

    Song, C.; Saini, A.; Huang, L.; Wenzel, K.; Hatcher, P.G.; Schobert, H.H.

    1992-01-01

    Low-temperature catalytic pretreatment is a promising approach to the development of an improved liquefaction process. This work is a fundamental study on effects of pretreatments on coal structure and reactivity in liquefaction. The main objectives of this project are to study the coal structural changes induced by low-temperature catalytic and thermal pretreatments by using spectroscopic techniques; and to clarify the pretreatment-induced changes in reactivity or convertibility of coals in the subsequent liquefaction. This report describes the progress of our work during the first quarterly period. Substantial progress has been made in the spectroscopic characterization of fresh and THF-extracted samples of two subbituminous coals and fresh samples of three bituminous coals using cross-polarization magic angle spinning (CPMAS) solid state {sup 13}C NMR and pyrolysis-GC-MS techniques. CPMAS {sup 13}C NMR and pyrolysis-GC-MS provided important information on carbon distribution/functionality and molecular components/structural units, respectively, for these coal samples. Pyrolysis-GC-MS revealed that there are remarkable structural differences in structural units between the subbituminous coals and the bituminous coals. Furthermore, significant progress has been made in the pretreatments and spectroscopic characterization of catalytically and thermally pretreated as well as physically treated Wyodak subbituminous coal, and temperature-staged and temperature-programmed thermal and catalytic liquefaction of a Montana subbituminous coal.

  14. Interconnected Levels of Multi-Stage Marketing

    DEFF Research Database (Denmark)

    Vedel, Mette; Geersbro, Jens; Ritter, Thomas

    2012-01-01

    Multi-stage marketing gains increasing attention as knowledge of and influence on the customer's customer become more critical for the firm's success. Despite this increasing managerial relevance, systematic approaches for analyzing multi-stage marketing are still missing. This paper conceptualizes...... different levels of multi-stage marketing and illustrates these stages with a case study. In addition, a triadic perspective is introduced as an analytical tool for multi-stage marketing research. The results from the case study indicate that multi-stage marketing exists on different levels. Thus, managers...... must not only decide in general on the merits of multi-stage marketing for their firm, but must also decide on which level they will engage in multi-stage marketing. The triadic perspective enables a rich and multi-dimensional understanding of how different business relationships influence each other...

  15. Multi-stage complex contagions

    Science.gov (United States)

    Melnik, Sergey; Ward, Jonathan A.; Gleeson, James P.; Porter, Mason A.

    2013-03-01

    The spread of ideas across a social network can be studied using complex contagion models, in which agents are activated by contact with multiple activated neighbors. The investigation of complex contagions can provide crucial insights into social influence and behavior-adoption cascades on networks. In this paper, we introduce a model of a multi-stage complex contagion on networks. Agents at different stages—which could, for example, represent differing levels of support for a social movement or differing levels of commitment to a certain product or idea—exert different amounts of influence on their neighbors. We demonstrate that the presence of even one additional stage introduces novel dynamical behavior, including interplay between multiple cascades, which cannot occur in single-stage contagion models. We find that cascades—and hence collective action—can be driven not only by high-stage influencers but also by low-stage influencers.

  16. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction. Technical progress report, July--September 1993

    Energy Technology Data Exchange (ETDEWEB)

    Song, C.; Saini, A.K.; Huang, L.; Schobert, H.H.; Hatcher, P.G.

    1994-01-01

    In this quarter, progress has been made in the following two aspects: (1) spectroscopic and chemical reaction studies on the effects of drying and mild oxidation of a Wyodak subbituminous coal on its structure and pretreatment/liquefaction at 350{degrees}C; and (2) effects of dispersed catalyst and solvent on conversion and structural changes of a North Dakota lignite. Drying and oxidation of Wyodak subbituminous coal at 100-150{degrees}C have been shown to have significant effects on its structure and on its catalytic and non-catalytic low-severity liquefaction at 350{degrees}C for 30 min under 6.9 MPa H{sub 2}. Spectroscopic analyses using solid-state {sup 13}C NMR, Pyrolysis-GC-MS, and FT-IR revealed that oxidative drying at 100-150{degrees}C causes the transformation of phenolics and catechol into other related structures (presumably via condensation) and high-severity air drying at 150{degrees}C for 20 h leads to disappearance of catechol-like structure. Increasing air drying time or temperature increases oxidation to form more oxygen functional groups at the expense of aliphatic carbons. Such a clearly negative impact of severe oxidation is considered to arise from significantly increased oxygen functionality which enhances the cross-link formation in the early stage of coal liquefaction. Physical, chemical, and surface physicochemical aspects of drying and oxidation and the role of water are also discussed. A North Dakota lignite (DECS-1) coal was studied for its behaviors in non-catalytic and catalytic liquefaction. Reactions were carried out at temperatures between 250 and 450{degrees}C. Regardless the reaction solvents and the catalyst being used, the optimum temperature was found to be 400{degrees}C. The donor solvent has a significant effect over the conversion especially at temperatures higher than 350{degrees}C.

  17. 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 (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, HTA: coal, water: coal respectively. With the oil price increase and growing in energy demand, the coal liquefaction remain affordable and available energy alternative.

  18. Impact of heterotrophically stressed algae for biofuel production via hydrothermal liquefaction and catalytic hydrotreating in continuous-flow reactors

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, Karl O.; Zhu, Yunhua; Schmidt, Andrew J.; Billing, Justin M.; Hart, Todd R.; Jones, Susanne B.; Maupin, Gary; Hallen, Richard; Ahrens, Toby; Anderson, Daniel

    2016-03-01

    Two algal feedstocks were prepared for direct comparison of their properties when converted to liquid hydrocarbon fuel. The first feedstock was prepared by growing an algal strain phototrophically using a bio-film based approach. The second feedstock employed the same algal strain but was stressed heterotrophically to significantly increase the lipid concentration. The algal feedstocks were converted to liquid hydrocarbon fuels. First, the whole algae (i.e. not defatted or lipid extracted) were converted to an intermediate biocrude using continuous hydrothermal liquefaction (HTL) at 350°C and 3000 psig. The biocrudes were subsequently upgraded via catalytic hydrotreating (HT) at 400°C and 1500 psig to remove oxygen and nitrogen as well as increase the hydrogen-to-carbon ratio. The yield and composition of the products from HTL and HT processing of the feedstocks are compared. A techno-economic analysis of the process for converting each feedstock to liquid fuels was also conducted. The capital and operating costs associated with converting the feedstocks to finished transportation fuels are reported. A fuel minimum selling price is presented as a function of the cost of the algal feedstock delivered to the HTL conversion plant.

  19. Low-severity catalytic two-stage liquefaction process: Illinois coal conceptual commercial plant design and economics

    Energy Technology Data Exchange (ETDEWEB)

    Abrams, L.M.; Comolli, A.G.; Popper, G.A.; Wang, C.; Wilson, G.

    1988-09-01

    Hydrocarbon Research, Inc. (HRI) is conducting a program for the United States Department of Energy (DOE) to evaluate a Catalytic Two-Stage Liquefaction (CTSL) Process. This program which runs through 1987, is a continuation of an earlier DOE sponsored program (1983--1985) at HRI to develop a new technology concept for CTSL. The earlier program included bench-scale testing of improved operating conditions for the CTSL Process on Illinois No. 6 bituminous coal and Wyoming sub-bituminous coal, and engineering screening studies to identify the economic incentive for CTSL over the single-stage H-Coal/reg sign/ Process for Illinois No. 6 coal. In the current program these engineering screening studies are extended to deep-cleaned Illinois coal and use of heavy recycle. The results from this comparison will be used as a guide for future experiments with respect to selection of coal feedstocks and areas for further process optimization. A preliminary design for CTSL of Illinois deep-cleaned coal was developed based on demonstrated bench-scale performance in Run No. 227-47(I-27), and from HRI's design experience on the Breckinridge Project and H-Coal/reg sign/ Process pilot plant operations at Catlettsburg. Complete conceptual commercial plant designs were developed for a grassroots facility using HRI's Process Planning Model. Product costs were calculated and economic sensitivities analyzed. 14 refs., 11 figs., 49 tabs.

  20. Experiments for Multi-Stage Processes

    DEFF Research Database (Denmark)

    Tyssedal, John; Kulahci, Murat

    2015-01-01

    Multi-stage processes are very common in both process and manufacturing industries. In this article we present a methodology for designing experiments for multi-stage processes. Typically in these situations the design is expected to involve many factors from different stages. To minimize...... the required number of experimental runs, we suggest using mirror image pairs of experiments at each stage following the first. As the design criterion, we consider their projectivity and mainly focus on projectivity 3 designs. We provide the methodology for generating these designs for processes with any...

  1. Multi-Stage Programs are Generalized Arrows

    CERN Document Server

    Megacz, Adam

    2010-01-01

    The lambda calculus, subject to typing restrictions, provides a syn- tax for the internal language of cartesian closed categories. This paper establishes a parallel result: staging annotations, subject to named level restrictions, provide a syntax for the internal language of Freyd categories, which are known to be in one-to-one correspondence with Arrows. The connection is made by interpreting multi-stage type systems as indexed functors from polynomial categories to their reindexings (Definitions 15 and 16). This result applies only to multi-stage languages which are (1) homogeneous, (2) allow cross-stage persistence and (3) place no restrictions on the use of structural rules in typing derivations. Removing these restrictions and repeating the construction yields generalized arrows, of which Arrows are a particular case. A translation from well-typed multi-stage programs to single-stage GArrow terms is provided. The translation is defined by induction on the structure of the proof that the multi-stage prog...

  2. Multi-stage LTL transport systems in supply chain management

    OpenAIRE

    Gonzalez-Feliu, Jesus

    2013-01-01

    This paper aims to unify concepts and to describe the multi-stage transport systems and their integratyion to supply chain management. Multi-stage distribution systems are common logistics management, and often they are assimilated to multi-stage transport strategies. However, transport is often considered as an external operation or a specific stage, even when it is a multi-stage system. First, the paper presents the main concepts of multi-stage transport systems by defining the concept an m...

  3. Coal liquefaction technology. (Latest citations from the NTIS Bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The bibliography contains citations concerning the technologies and processes for converting coal to liquid chemicals and fuels. Topics include materials characterization of liquefaction processes, catalysis, pyrolysis, depolymerization, coprocessing, and integrated liquefaction. Also discussed are liquid fuel use in automobiles and power generation, low-temperature carbonization technology, multi-stage liquefaction, cost benefit analysis, and commercialization of liquefaction technology. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  4. Multi-stage sampling in genetic epidemiology.

    Science.gov (United States)

    Whittemore, A S; Halpern, J

    When data are expensive to collect, it can be cost-efficient to sample in two or more stages. In the first stage a simple random sample is drawn and then stratified according to some easily measured attribute. In each subsequent stage a random subset of previously selected units is sampled for more detailed observation, with a unit's sampling probability determined by its attributes as observed in the previous stages. These designs are useful in many medical studies; here we use them in genetic epidemiology. Two genetic studies illustrate the strengths and limitations of the approach. The first study evaluates nuclear and mitochondrial DNA in U.S. blacks. The goal is to estimate the relative contributions of white male genes and white female genes to the gene pool of African-Americans. This example shows that the Horvitz-Thompson estimators proposed for multi-stage designs can be inefficient, particularly when used with unnecessary stratification. The second example is a multi-stage study of familial prostate cancer. The goal is to gather pedigrees, blood samples and archived tissue for segregation and linkage analysis of familial prostate cancer data by first obtaining crude family data from prostate cancer cases and cancer-free controls. This second example shows the gains in efficiency from multi-stage sampling when the individual likelihood or quasilikelihood scores vary substantially across strata. PMID:9004389

  5. Interconnected levels of multi-stage marketing: A triadic approach

    OpenAIRE

    Vedel, Mette; Geersbro, Jens; Ritter, Thomas

    2012-01-01

    Multi-stage marketing gains increasing attention as knowledge of and influence on the customer's customer become more critical for the firm's success. Despite this increasing managerial relevance, systematic approaches for analyzing multi-stage marketing are still missing. This paper conceptualizes different levels of multi-stage marketing and illustrates these stages with a case study. In addition, a triadic perspective is introduced as an analytical tool for multi-stage marketing research. ...

  6. Multi Staged Gasification Systems - A New Approach

    Energy Technology Data Exchange (ETDEWEB)

    Huber, M.B.; Koidl, F.; Kreutner, G.; Giovannini, A. (MCI - Univ. of Applied Science for Environmental-, Process- and Biotechnology, A-6020 Innsbruck (Austria)); Kleinhappl, M.; Roschitz, C.; Hofbauer, H. (Austrian Bioeneregy Centre, Graz (Austria)); Gruber, F. (GE Jenbacher, Jenbach (Austria)); Krueger, J. (SynCraft Engineering, Schwaz (Austria))

    2008-10-15

    Multi-staged fixed bed (MFB) gasification systems represent one of the most promising and effective methods of transforming solid biomass into power and heat (CHP). The underlying magic of this gasification process is, that a clean producer gas suitable for gas engines at high cold-gas efficiency rates can be produced. These two attributes allow multi-staged gasification systems to minimize the efforts for gas cleaning, while maximizing the energy retrieval out of the biomass. Though already demonstrated in small-scale, MFB gasification becomes a challenge when thinking of commercial-sized plants above 150kW{sub el}. In such a dimension especially the pressure loss over the char bed and bulk instabilities become the major process obstacles. After years of investigation the MCI developed a new process pathway which allows avoiding these bottle necks while maintaining the advantages of MFB systems. The core of the new staged alignment is the combination of a partial-oxidation-accelerator with a floating-bed-reduction-reactor. The process has already achieved technical proof of concept during ongoing investigations at a 250 kW{sub th} pilot plant in Jenbach and will be upscaled to demonstration plant size as soon as sufficient long time experience is gained

  7. Multi-stage magnetic induction mass accelerator

    International Nuclear Information System (INIS)

    The magnetic induction method of mass acceleration readily lends itself to multi-staging. In the limit of many stages, such an accelerator approaches a distributed energy source system where only closing switches are necessary. We describe the design and performance of a three-stage accelerator, each driven by a separate capacitor bank. This system was modeled using a previously reported computer code. In order to do this the code was modified to calculate projectile acceleration through a succession of driver coils: Thermal conductivity and surface melting models were also added. The former is necessary due to the extended transit time through many stages. The latter is needed in anticipation of the more extreme ohmic heating when the capacitor banks are replaced by explosive-driven, magnetic flux compression generators. The performance goal of this system is to at least double the kinetic energy of a 0.3 kgm copperclad, steel projectile injected at a velocity of 300 m/sec from an explosive-driven gun. We then plan to test the system at the thermal and mechanical limit by using explosive-driven, magnetic flux compression generators as energy sources. We envision a six-stage system driven by three generators

  8. Catalytic Two-Stage Liquefaction (CTSL{trademark}) process bench studies and PDU scale-up with sub-bituminous coal. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Comolli, A.G.; Johanson, E.S.; Karolkiewicz, W.F.; Lee, L.K.T.; Stalzer, R.H.; Smith, T.O.

    1993-03-01

    Reported are the details and results of Laboratory and Bench-Scale experiments using sub-bituminous coal conducted at Hydrocarbon Research, Inc., under DOE Contract No. DE-AC22-88PC88818 during the period October 1, 1988 to December 31, 1992. The work described is primarily concerned with testing of the baseline Catalytic Two-Stage Liquefaction (CTSL{trademark}) process with comparisons with other two stage process configurations, catalyst evaluations and unit operations such as solid separation, pretreatments, on-line hydrotreating, and an examination of new concepts. In the overall program, three coals were evaluated, bituminous Illinois No. 6, Burning Star and sub-bituminous Wyoming Black Thunder and New Mexico McKinley Mine seams. The results from a total of 16 bench-scale runs are reported and analyzed in detail. The runs (experiments) concern process variables, variable reactor volumes, catalysts (both supported, dispersed and rejuvenated), coal cleaned by agglomeration, hot slurry treatments, reactor sequence, on-line hydrotreating, dispersed catalyst with pretreatment reactors and CO{sub 2}/coal effects. The tests involving the Wyoming and New Mexico Coals are reported herein, and the tests involving the Illinois coal are described in Topical Report No. 2. On a laboratory scale, microautoclave tests evaluating coal, start-up oils, catalysts, thermal treatment, CO{sub 2} addition and sulfur compound effects were conducted and reported in Topical Report No. 3. Other microautoclave tests are described in the Bench Run sections to which they refer such as: rejuvenated catalyst, coker liquids and cleaned coals. The microautoclave tests conducted for modelling the CTSL{trademark} process are described in the CTSL{trademark} Modelling section of Topical Report No. 3 under this contract.

  9. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction. Final technical report, Volume 2 - hydrogenative and hydrothermal pretreatments and spectroscopic characterization using pyrolysis-GC-MS, CPMAS {sup 13}C NMR and FT-IR

    Energy Technology Data Exchange (ETDEWEB)

    Chunshan Song; Hatcher, P.G.; Saini, A.K.; Wenzel, K.A.

    1998-01-01

    It has been indicated by DOE COLIRN panel that low-temperature catalytic pretreatment is a promising approach to the development of an improved liquefaction process. This work is a fundamental study on effects of pretreatments on coal structure and reactivity in liquefaction. The main objectives of this project are to study the coal structural changes induced by low-temperature catalytic and thermal pretreatments by using spectroscopic techniques; and to clarify the pretreatment-induced changes in reactivity or convertibility of coals. As the second volume of the final report, here we summarize our work on spectroscopic characterization of four raw coals including two subbituminous coals and two bituminous coals, tetrahydrofuran (THF)-extracted but unreacted coals, the coals (THF-insoluble parts) that have been thermally pretreated. in the absence of any solvents and in the presence of either a hydrogen-donor solvent or a non-donor solvent, and the coals (THF-insoluble parts) that have been catalytically pretreated in the presence of a dispersed Mo sulfide catalyst in the absence of any solvents and in the presence of either a hydrogen-donor solvent or a non-donor solvent.

  10. PARALLEL MULTI-STAGE & MULTI-STEP METHOD IN ODES

    Institute of Scientific and Technical Information of China (English)

    Xiao-qiu Song

    2000-01-01

    In this paper, the theory of parallel multi-stage & multi-step method is dis cussed, which is a form of combining Runge-Kutta method with linear multi-step method that can be used for parallel computation.

  11. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction. Final technical report, Volume 1 - effects of solvents, catalysts and temperature conditions on conversion and structural changes of low-rank coals

    Energy Technology Data Exchange (ETDEWEB)

    Lili Huang; Schobert, H.H.; Chunshan Song

    1998-01-01

    The main objectives of this project were to study the effects of low-temperature pretreatments on coal structure and their impacts on subsequent liquefaction. The effects of pretreatment temperatures, catalyst type, coal rank, and influence of solvent were examined. Specific objectives were to identify the basic changes in coal structure induced by catalytic and thermal pretreatments, and to determine the reactivity of the catalytically and thermally treated coals for liquefaction. In the original project management plan it was indicated that six coals would be used for the study. These were to include two each of bituminous, subbituminous, and lignite rank. For convenience in executing the experimental work, two parallel efforts were conducted. The first involved the two lignites and one subbituminous coal; and the second, the two bituminous coals and the remaining subbituminous coal. This Volume presents the results of the first portion of the work, studies on two lignites and one subbituminous coal. The remaining work accomplished under this project will be described and discussed in Volume 2 of this report. The objective of this portion of the project was to determine and compare the effects of solvents, catalysts and reaction conditions on coal liquefaction. Specifically, the improvements of reaction conversion, product distribution, as well as the structural changes in the coals and coal-derived products were examined. This study targeted at promoting hydrogenation of the coal-derived radicals, generated during thermal cleavage of chemical bonds, by using a good hydrogen donor-solvent and an effective catalyst. Attempts were also made in efforts to match the formation and hydrogenation of the free radicals and thus to prevent retrogressive reaction.

  12. Improved Heuristics for Multi-Stage Requirements Planning Systems

    OpenAIRE

    Joseph D. Blackburn; Robert A. Millen

    1982-01-01

    Most of the recent studies of heuristic lot-sizing techniques for multi-stage material requirements planning systems have investigated the problem in the context of a single stage. In this paper, the multi-stage problem is first modeled analytically to indicate the potential errors inherent in the commonly proposed single-pass, stage-by-stage approaches (e.g., Wagner-Whitin). Then, based on this analysis, several simple cost modifications are suggested to improve the global optimality of thes...

  13. Accuracy of transferring microparts in a multi stage former

    DEFF Research Database (Denmark)

    Mahshid, Rasoul; Hansen, Hans Nørgaard; Arentoft, Mogens

    2013-01-01

    Many fasteners used in electromechanical systems are micro metal parts which should be manufactured with high accuracy and reliability and in large quantities. Micro forming is promising to fulfill these demands. This research focuses on investigating a gripping unit in a multi stage former, as t...

  14. Information Overload in Multi-Stage Selection Procedures

    NARCIS (Netherlands)

    S.S. Ficco (Stefano); V.A. Karamychev (Vladimir)

    2004-01-01

    textabstractThe paper studies information processing imperfections in a fully rational decision-making network. It is shown that imperfect information transmission and imperfect information acquisition in a multi-stage selection game yield information overload. The paper analyses the mechanisms resp

  15. Effect of properties of iron compounds on the catalytic activity in direct coal liquefaction; Tetsu kagobutsu no keitai to sekitan ekika kassei

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, T.; Tazawa, K. [Mitsubishi Chemical Corp., Tokyo (Japan); Shimasaki, K. [Kobe Steel Ltd. (Japan)

    1998-08-20

    When considering merchandising scale of the coal liquefaction process, it is a preliminary condition that metal used for its catalyst is rich in resource volume, cheap in production cost, without pollution, and so forth, and application of cheap iron ore and ferrous compounds to disposable catalyst is desired. As liquefaction activity of the iron ore was hitherto improved by its micro crushing, its mechanical crush had a limit of about 2 {mu}m in mean particle diameter. However, together with recent crushing technique, crushers with high performance were developed, and then micro crushing by sub-micron became possible industri8ally even for iron ore. In this study, three kinds of Australian iron ores such as limonite of ferric hydroxide type iron ore, pyrite of ferrous sulfide type, and hematite of ferric oxide type were micro crushed to examine coal liquefaction activity and hydrogenation reaction activity of 1-methyl naphthalene (1-MN) and also relationship between properties and activity of catalyst for the latter before and after reaction. 11 refs., 8 figs., 5 tabs.

  16. Performance of Multi-Channel Multi-Stage Spectrum Sensing

    CERN Document Server

    Gabran, Wesam; Čabrić, Danijela

    2010-01-01

    We present an analytical framework which enables performance evaluation of different multi-channel multi-stage spectrum sensing protocols for Opportunistic Spectrum Access networks. Analyzed performance metrics include the average secondary user throughput and the average collision probability between the primary and secondary users. The analysis framework takes into account buffering of incoming secondary user traffic, parallel and single channel access, as well as prolonged channel observation periods at the first and last stage of sensing. The main results show that when a constraint is given upon the probability of primary user mis-detection, multi-stage sensing is in most cases superior to the single stage sensing counterpart. Further, prolonged channel observation at the first sensing stage decreases the collision probability considerably while keeping the throughput at an acceptable level. Finally, in most network scenarios considered in this work, two stages of sensing are enough to obtain the maximum...

  17. Process for multi-stage treatment of radioactive waste water

    International Nuclear Information System (INIS)

    For the multi-stage treatment of radioactive waste waters with a decanter the solids contained in the waste waters are dried up to a residual moisture of 10% and are subsequently disposed. Solids remaining in the liquid part are removed with a separator up to the colloidal range, whereas the liquid product of the decanter is filtered up to the molecular range so that it can be used as industrial water. (orig.)

  18. Multi-Stage Transportation Problem With Capacity Limit

    OpenAIRE

    I. Brezina; Z. Čičková; J. Pekár; M. Reiff

    2010-01-01

    The classical transportation problem can be applied in a more general way in practice. Related problems as Multi-commodity transportation problem, Transportation problems with different kind of vehicles, Multi-stage transportation problems, Transportation problem with capacity limit is an extension of the classical transportation problem considering the additional special condition. For solving such problems many optimization techniques (dynamic programming, linear programming, special algor...

  19. 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.

  20. Direct coal liquefaction using iron-titanium hydride as a hydrogen distribution and catalytic material. Yearly report No. 1, September 1, 1984-August 31, 1985

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.E. Jr.

    1985-09-29

    During this year the experimental apparatus was completed after substantial delays by the manufacturer and eight direct coal liquefaction experiments were accomplished. These experiments have produced conversion and selectivity data on samples of Utah coal slurried in tetralin and catalyzed using iron-titanium hydride. Hydrogen loading of the alloy, catalyst particle size, catalyst concentration, coal particle size, operating temperatures for alloy addition and liquefaction without the catalysts present, have all been studied during these experiments. Conversions as high as 61% DAF in 30 min have been recorded at 500/sup 0/F and 500 psia. Product selectivities favor the oil fraction during the initial phase of the reaction, but as the reaction proceeds the heavier fractions are observed to increase at the expense of the oil fraction. We are currently working on a kinetic model in an effort to predict these results. Additionally, proton NMR, fractional distillation, and chromatographic analyses are currently being performed on the recovered product. We have completed the study of Utah coal and are moving on to samples of Kentucky and Alabama coals after a minor modification of the experimental apparatus is completed. Equipment manufacture, delivery, and installation delays, totaling over 6 months, greatly reduced the time available for research, making a 6 month no cost extension necessary. The extended time will permit completion of the proposed research tasks. 10 figs., 8 tabs.

  1. 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

  2. 76 FR 19747 - Grant of Authority for Subzone Status; Grundfos Pumps Manufacturing Corporation (Multi-Stage...

    Science.gov (United States)

    2011-04-08

    ... (Multi-Stage Centrifugal Pumps); Allentown, PA Pursuant to its authority under the Foreign-Trade Zones... to the Board for authority to establish a special-purpose subzone at the multi-stage centrifugal pump... status for activity related to the manufacturing of multi-stage centrifugal pumps at the Grundfos...

  3. Dynamics of multi-stage infections on networks

    CERN Document Server

    Sherborne, N; Kiss, I Z

    2015-01-01

    This paper investigates the dynamics of infectious diseases with a non-exponentially distributed infectious period. This is achieved by considering a multi-stage infection model on networks. Using pairwise approximation with a standard closure, a number of important characteristics of disease dynamics are derived analytically, including the final size of an epidemic and a threshold for epidemic outbreaks. Stochastic simulations of dynamics on networks are performed and compared to the results of pairwise models for several realistic examples of infectious diseases to illustrate the role played by the number of stages in the disease dynamics. The agreement between the pairwise and simulation methods is excellent in the cases we consider.

  4. Mortgage Loan Portfolio Optimization Using Multi-Stage Stochastic Programming

    DEFF Research Database (Denmark)

    Rasmussen, Kourosh Marjani; Clausen, Jens

    2007-01-01

    We consider the dynamics of the Danish mortgage loan system and propose several models to reflect the choices of a mortgagor as well as his attitude towards risk. The models are formulated as multi stage stochastic integer programs, which are difficult to solve for more than 10 stages. Scenario...... reduction and LP relaxation are used to obtain near optimal solutions for large problem instances. Our results show that the standard Danish mortgagor should hold a more diversified portfolio of mortgage loans, and that he should rebalance the portfolio more frequently than current practice....

  5. Multi-stage apodized pupil Lyot coronagraph experimental results

    Science.gov (United States)

    Abe, L.; Venet, M.; Enya, K.; Kataza, H.; Nakagawa, T.; Tamura, M.

    2008-07-01

    Prolate (Pupil) Apodized Lyot Coronagraphs (PPALC) are known to offer optimal performances for a Lyot-type Coronagraph configuration, i.e. with an opaque occulting focal mask. One additional benefit of PPALC is its possible use in a multi-stage configuration. In theory, the coronagraphic performance can be QN, where Q is the energy rejection factor of one stage (the first one), and N the number of stages. Several ground-based telescopes are considering PPALC as an option for their high-contrast instrumentation (e.g. Gemini/GPI, EELT/EPICS, Subaru HiCIAO). Although the PPALC suffers from several limitations, several works are currently focused on fabricating entrance pupil apodizers and trying to find ways to overcome chromatism issues. In this work, we present the first experimental results from Multi-Stage PPALC (MS-PPALC) that was done in the context of the Japanese space telescope SPICA coronagraph project. Our entrance pupil apodizers use small diameter High Energy Beam Sensitive glass (HEBS-glass) from Canyon Materials Inc. The current results show modest coronagraphic performance due to uncompensated phase aberrations inherent to HEBS-glass material. In addition, and due to these uncompensated phase aberrations, the present optical configuration is an altered version of the originally planned set-up. However, we can demonstrate the validity the MS-PPALC concept and compare it to numerical simulations.

  6. Multi-stage circulating fluidized bed syngas cooling

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guohai; Vimalchand, Pannalal; Guan, Xiaofeng; Peng, WanWang

    2016-10-11

    A method and apparatus for cooling hot gas streams in the temperature range 800.degree. C. to 1600.degree. C. using multi-stage circulating fluid bed (CFB) coolers is disclosed. The invention relates to cooling the hot syngas from coal gasifiers in which the hot syngas entrains substances that foul, erode and corrode heat transfer surfaces upon contact in conventional coolers. The hot syngas is cooled by extracting and indirectly transferring heat to heat transfer surfaces with circulating inert solid particles in CFB syngas coolers. The CFB syngas coolers are staged to facilitate generation of steam at multiple conditions and hot boiler feed water that are necessary for power generation in an IGCC process. The multi-stage syngas cooler can include internally circulating fluid bed coolers, externally circulating fluid bed coolers and hybrid coolers that incorporate features of both internally and externally circulating fluid bed coolers. Higher process efficiencies can be realized as the invention can handle hot syngas from various types of gasifiers without the need for a less efficient precooling step.

  7. Numerical Simulation of Multi-Stage Turbomachinery Flows

    Science.gov (United States)

    Adamczyk, John J.; Hathaway, Michael D.; Shabbir, Aamir; Wellborn, Steven R.

    1999-01-01

    A comprehensive assessment is made of the predictive capability of the average passage flow model as applied to multi-stage axial flow compressors. The average passage flow model describes the time average flow field within a typical passage of a blade row embedded in a multi-stage configuration. In this work data taken within a four and one-half stage large low speed compressor will be used to assess the weakness and strengths of the predictive capabilities of the average passage flow model. The low speed compressor blading is of modern design and employs stators with end-bends. Measurements were made with slow and high response instrumentation. The high response measurements revealed the velocity components of both the rotor and stator wakes. Based on the measured wake profiles it will be argued that blade boundary layer transition is playing an important role in setting compressor performance. A model which mimics the effects of blade boundary layer transition within the frame work of the average passage model will be presented. Simulations which incorporated this model showed a dramatic improvement in agreement with data.

  8. Interconnected levels of Multi-Stage Marketing – A Triadic approach

    DEFF Research Database (Denmark)

    Vedel, Mette; Geersbro, Jens; Ritter, Thomas

    2012-01-01

    Multi-stage marketing gains increasing attention as knowledge of and influence on the customer's customer become more critical for the firm's success. Despite this increasing managerial relevance, systematic approaches for analyzing multi-stage marketing are still missing. This paper conceptualizes...... different levels of multi-stage marketing and illustrates these stages with a case study. In addition, a triadic perspective is introduced as an analytical tool for multi-stage marketing research. The results from the case study indicate that multi-stage marketing exists on different levels. Thus, managers...... must not only decide in general on the merits of multi-stage marketing for their firm, but must also decide on which level they will engage in multi-stage marketing. The triadic perspective enables a rich and multi-dimensional understanding of how different business relationships influence each other...

  9. Axial flow, multi-stage turbine and compressor models

    International Nuclear Information System (INIS)

    Design models of multi-stage, axial-flow turbine and compressor are developed for high temperature nuclear reactor power plants with Closed Brayton Cycle for energy conversion. The models are based on a mean-line through-flow analysis for free-vortex flow, account for the profile, secondary, end wall, trailing edge and tip clearance losses in the cascades, and calculate the geometrical parameters of the blade cascades. The effects of the mean-stage work coefficient, flow coefficient and stage reaction on the design and performance of helium turbine and compressor are investigated. The results compare favorably with those reported for 6 stages helium turbine and 20 stages helium compressor. Also presented and discussed are the results of parametric analyses of a 530-MW helium turbine, and a 251-MW helium compressor.

  10. Chemistry and catalysis of coal liquefaction: catalytic and thermal upgrading of coal liquid and hydrogenation of CO to produce fuels. Quarterly progress report, January-March 1980

    Energy Technology Data Exchange (ETDEWEB)

    Wiser, W.H.

    1980-08-01

    Analysis of a group of coal liquids produced by catalytic hydrogenation of Utah coals with ZnCl/sub 2/ catalyst was begun. Carbon-13 nuclear magnetic resonance and liquid chromatography techniques will be used to correlate chemical properties with hydrogenation reactivity. Equipment previously used for downflow measurements of heat and momentum transfer in a gas-coal suspension was modified for upflow measurements. The catalytic hydrodeoxygenation of methyl benzoate has been studied to elucidate the reactions of ester during upgrading of coal-derived liquids. The kinetics of hydrogenation of phenanthrene have also been determined. The catalytic cracking mechanism of octahydroanthracene is reported in detail. Studies of the hydrodesulfurization of thiophene indicate that some thiophene is strongly adsorbed as a hydrogen-deficient polymer on cobalt-molybdate catalyst. Part of the polymer can be desorbed as thiophene by hydrogenation. Poisoning of the catalyst inhibits the hydrosulfurization activity to a greater degree than the hydrogenation activity. Iron-manganese catalysts for carbon monoxide hydrogenation is studied to determine the role of iron carbide formation on selectivity. Pure iron catalyst forms a Hagg iron carbide phase under reaction conditions.

  11. Controllability in Multi-Stage Laser Ion Acceleration

    Science.gov (United States)

    Kawata, S.; Kamiyama, D.; Ohtake, Y.; Barada, D.; Ma, Y. Y.; Kong, Q.; Wang, P. X.; Gu, Y. J.; Li, X. F.; Yu, Q.

    2015-11-01

    The present paper shows a concept for a future laser ion accelerator, which should have an ion source, ion collimators, ion beam bunchers and ion post acceleration devices. Based on the laser ion accelerator components, the ion particle energy and the ion energy spectrum are controlled, and a future compact laser ion accelerator would be designed for ion cancer therapy or for ion material treatment. In this study each component is designed to control the ion beam quality. The energy efficiency from the laser to ions is improved by using a solid target with a fine sub-wavelength structure or a near-critical density gas plasma. The ion beam collimation is performed by holes behind the solid target or a multi-layered solid target. The control of the ion energy spectrum and the ion particle energy, and the ion beam bunching are successfully realized by a multi-stage laser-target interaction. A combination of each component provides a high controllability of the ion beam quality to meet variable requirements in various purposes in the laser ion accelerator. The work was partly supported by MEXT, JSPS, ASHULA project/ ILE, Osaka University, CORE (Center for Optical Research and Education, Utsunomiya University, Japan), Fudan University and CDI (Creative Dept. for Innovation) in CCRD, Utsunomiya University.

  12. Multi-stage FE simulation of hot ring rolling

    Science.gov (United States)

    Wang, C.; Geijselaers, H. J. M.; van den Boogaard, A. H.

    2013-05-01

    As a unique and important member of the metal forming family, ring rolling provides a cost effective process route to manufacture seamless rings. Applications of ring rolling cover a wide range of products in aerospace, automotive and civil engineering industries [1]. Above the recrystallization temperature of the material, hot ring rolling begins with the upsetting of the billet cut from raw stock. Next a punch pierces the hot upset billet to form a hole through the billet. This billet, referred to as preform, is then rolled by the ring rolling mill. For an accurate simulation of hot ring rolling, it is crucial to include the deformations, stresses and strains from the upsetting and piercing process as initial conditions for the rolling stage. In this work, multi-stage FE simulations of hot ring rolling process were performed by mapping the local deformation state of the workpiece from one step to the next one. The simulations of upsetting and piercing stages were carried out by 2D axisymmetric models using adaptive remeshing and element erosion. The workpiece for the ring rolling stage was subsequently obtained after performing a 2D to 3D mapping. The commercial FE package LS-DYNA was used for the study and user defined subroutines were implemented to complete the control algorithm. The simulation results were analyzed and also compared with those from the single-stage FE model of hot ring rolling.

  13. Multi-stage Stochastic Programming Models in Production Planning

    Directory of Open Access Journals (Sweden)

    Abas Esmaeili

    2013-10-01

    Full Text Available Production planing is a key area of operations management. An important methodology for production planing is mathematical programming. Traditonal mathematical programming models for production planing are deterministic, and canot provide robust production plans in the presence of uncertainty. As such, deterministic planing models may yield unsatisfactory decisions. Stochastic programming, an active branch of mathematical programming dealing with optimization problems involving uncertain data, has sen several sucesful aplications in production planing. Unlike alternative aproaches to decision making under uncertainty, such as Markov decision proceses, stochastic programming requires few asumptions on the underlying stochastic proceses and alows for modeling of complicated decision structures. On the other hand, stochastic programming asumes finite number of stages and exogenous uncertainties. With recent increase in computational power and algorithmic developments, the limitations of stochastic programming arising from computational dificulties have ben relieved to a large extent. Nowadays, god production planing is a considered as one of the reason for improvement in production and many studies have ben conducted in order to identify the models of production planing. The main purpose of this research is to study multi-stage stochastic programming models in production planing.

  14. Energy efficiency of multi-stage adsorption drying for low-temperature drying

    NARCIS (Netherlands)

    Djaeni, M.; Straten, van G.; Bartels, P.V.; Sanders, J.P.M.; Boxtel, van A.J.B.

    2009-01-01

    This work discusses the evaluation of multi-stage adsorption dryers with air dehumidification by zeolite and alumina pillared clay. In a multi-stage dryer, product is dried in succeeding stages while air leaving a stage is fed to the next stage after dehumidification by an adsorbent. Energy efficien

  15. Bodypart Recognition Using Multi-stage Deep Learning.

    Science.gov (United States)

    Yan, Zhennan; Zhan, Yiqiang; Peng, Zhigang; Liao, Shu; Shinagawa, Yoshihisa; Metaxas, Dimitris N; Zhou, Xiang Sean

    2015-01-01

    Automatic medical image analysis systems often start from identifying the human body part contained in the image; Specifically, given a transversal slice, it is important to know which body part it comes from, namely "slice-based bodypart recognition". This problem has its unique characteristic--the body part of a slice is usually identified by local discriminative regions instead of global image context, e.g., a cardiac slice is differentiated from an aorta arch slice by the mediastinum region. To leverage this characteristic, we design a multi-stage deep learning framework that aims at: (1) discover the local regions that are discriminative to the bodypart recognition, and (2) learn a bodypart identifier based on these local regions. These two tasks are achieved by the two stages of our learning scheme, respectively. In the pre-train stage, a convolutional neural network (CNN) is learned in a multi-instance learning fashion to extract the most discriminative local patches from the training slices. In the boosting stage, the learned CNN is further boosted by these local patches for bodypart recognition. By exploiting the discriminative local appearances, the learned CNN becomes more accurate than global image context-based approaches. As a key hallmark, our method does not require manual annotations of the discriminative local patches. Instead, it automatically discovers them through multi-instance deep learning. We validate our method on a synthetic dataset and a large scale CT dataset (7000+ slices from wholebody CT scans). Our method achieves better performances than state-of-the-art approaches, including the standard CNN. PMID:26221694

  16. Hydrothermal liquefaction of biomass

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Hoffmann, Jessica;

    2014-01-01

    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. Cooperative research program in coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Huffman, G.P. (ed.)

    1991-01-01

    This Quarterly Report on coal liquefaction research includes discussion in the areas of (1) Iron Based Catalysts for Coal Liquefaction; (2) Exploratory Research on Coal Conversion; (3) Novel Coal Liquefaction Concepts; (4) Novel Catalysts for Coal Liquefaction. (VC)

  18. Multi-stage and multi-orifice throttling analysis for thermal power generating sets

    Institute of Scientific and Technical Information of China (English)

    郭茂林; 王刚; 张瑞

    2002-01-01

    Multi-stage and multi-orifice throttling analysis for bypass valves in thermal power generating sets is important for normal operation of power generating equipment. It is improper to exclude the factor of flow resistance from the expansion coefficient for the flow formula used for analysing the multi-stage and multi-orifice flow of compressible fluid, which means expansion of gas has nothing to do with resistance. The authors put forward an expanded energy equation and related formula to overcome the drawback, and use them for multi-stage and multi-orifice throttling analysis of compressible fluid for thermal power generating sets.

  19. Mean squared error properties of the kernel-based multi-stage median predictor for time series

    NARCIS (Netherlands)

    J.G. de Gooijer; A. Gannoun; D. Zerom Godefay

    2002-01-01

    We propose a kernel-based multi-stage conditional median predictor for -mixing time series of Markovian structure. Mean squared error properties of single-stage and multi-stage conditional medians are derived and discussed.

  20. Coal liquefaction. Quarterly report, January--March 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-12-01

    Current ERDA work in coal liquefaction is aimed at improved process configurations for both catalytic and non-catalytic processes to provide more attractive processing economics and lower capital investment. Coal liquefaction can now be achieved under more moderate processing conditions and more rapidly than was the case in the 1930's. The advantage of coal liquefaction is that the entire range of liquid products, including heavy boiler fuel, distillate fuel oil, gasoline, jet fuel, and diesel oil, can be produced from coal by varying the type of process and operating conditions used in the process. Furthermore, coal-derived liquid fuels also have the potential for use as chemical feedstocks. To determine the most efficient means of utilizing coal resources, ERDA is sponsoring the development of several conversion processes that are currently in the pilot plant stage. Nineteen projects under development are described and progress for each in the quarter is detailed briefly. (LTN)

  1. 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.

  2. 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...

  3. Throughput and Collision Analysis of Multi-Channel Multi-Stage Spectrum Sensing Algorithms

    OpenAIRE

    Gabran, Wesam; Pawełczak, Przemysław; Čabrić, Danijela

    2010-01-01

    Multi-stage sensing is a novel concept that refers to a general class of spectrum sensing algorithms that divide the sensing process into a number of sequential stages. The number of sensing stages and the sensing technique per stage can be used to optimize performance with respect to secondary user throughput and the collision probability between primary and secondary users. So far, the impact of multi-stage sensing on network throughput and collision probability for a realistic network mode...

  4. Reduced models of multi-stage cyclic structures using cyclic symmetry reduction and component mode synthesis

    Science.gov (United States)

    Tran, Duc-Minh

    2014-10-01

    Reduced models of multi-stage cyclic structures such as bladed-disk assemblies are developed by using the multi-stage cyclic symmetry reduction and/or component mode synthesis methods. The multi-stage cyclic symmetry reduction consists in writing the equations of the bladed disks, the inter-disk structures, the inter-disk constraints and the whole multi-stage coupled system in terms of the traveling wave coordinates for all the phase indexes of the reference sectors and for all the bladed disks. Several reduced coupled systems are then solved by selecting at each time only one or a few phase indexes for each bladed disk and by applying the cyclic symmetry boundary conditions. On the other hand, component mode synthesis methods are used either independently or in combination with the multi-stage cyclic symmetry reduction to obtain reduced models of the multi-stage structure. Two of them are particularly efficient, that are firstly component mode synthesis methods with interface modes applied on the bladed disks and secondly component mode synthesis methods with traveling wave coordinates applied on the reference sectors.

  5. 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.

  6. Coal liquefaction processes

    Energy Technology Data Exchange (ETDEWEB)

    Baker, N.R.; Blazek, C.F.; Tison, R.R.

    1979-07-01

    Coal liquefaction is an emerging technology receiving great attention as a possible liquid fuel source. Currently, four general methods of converting coal to liquid fuel are under active development: direct hydrogenation; pyrolysis/hydrocarbonization; solvent extraction; and indirect liquefaction. This work is being conducted at the pilot plant stage, usually with a coal feed rate of several tons per day. Several conceptual design studies have been published recently for large (measured in tens of thousands of tons per day coal feed rate) commercial liquefaction plants, and these reports form the data base for this evaluation. Products from a liquefaction facility depend on the particular method and plant design selected, and these products range from synthetic crude oils up through the lighter hydrocarbon gases, and, in some cases, electricity. Various processes are evaluated with respect to product compositions, thermal efficiency, environmental effects, operating and maintenance requirements, and cost. Because of the large plant capacities of current conceptual designs, it is not clear as to how, and on what scale, coal liquefaction may be considered appropriate as an energy source for Integrated Community Energy Systems (CES). Development work, both currently under way and planned for the future, should help to clarify and quantify the question of applicability.

  7. Adaptation of Decoy Fusion Strategy for Existing Multi-Stage Search Workflows

    Science.gov (United States)

    Ivanov, Mark V.; Levitsky, Lev I.; Gorshkov, Mikhail V.

    2016-06-01

    A number of proteomic database search engines implement multi-stage strategies aiming at increasing the sensitivity of proteome analysis. These approaches often employ a subset of the original database for the secondary stage of analysis. However, if target-decoy approach (TDA) is used for false discovery rate (FDR) estimation, the multi-stage strategies may violate the underlying assumption of TDA that false matches are distributed uniformly across the target and decoy databases. This violation occurs if the numbers of target and decoy proteins selected for the second search are not equal. Here, we propose a method of decoy database generation based on the previously reported decoy fusion strategy. This method allows unbiased TDA-based FDR estimation in multi-stage searches and can be easily integrated into existing workflows utilizing popular search engines and post-search algorithms.

  8. Strategies and limits in multi-stage single-point incremental forming

    DEFF Research Database (Denmark)

    Skjødt, Martin; Silva, M.B.; Martins, P. A. F.;

    2010-01-01

    Multi-stage single-point incremental forming (SPIF) is a state-of-the-art manufacturing process that allows small-quantity production of complex sheet metal parts with vertical walls. This paper is focused on the application of multi-stage SPIF with the objective of producing cylindrical cups with...... vertical walls. The strategy consists of forming a conical cup with a taper angle in the first stage, followed by three subsequent stages that progressively move the conical shape towards the desired cylindrical geometry. The investigation includes material characterization, determination of forming......-limit curves and fracture forming-limit curves (FFLCs), numerical simulation, and experimentation, namely the evaluation of strain paths and fracture strains in actual multi-stage parts. Assessment of numerical simulation with experimentation shows good agreement between computed and measured strain and strain...

  9. Adaptation of Decoy Fusion Strategy for Existing Multi-Stage Search Workflows

    Science.gov (United States)

    Ivanov, Mark V.; Levitsky, Lev I.; Gorshkov, Mikhail V.

    2016-09-01

    A number of proteomic database search engines implement multi-stage strategies aiming at increasing the sensitivity of proteome analysis. These approaches often employ a subset of the original database for the secondary stage of analysis. However, if target-decoy approach (TDA) is used for false discovery rate (FDR) estimation, the multi-stage strategies may violate the underlying assumption of TDA that false matches are distributed uniformly across the target and decoy databases. This violation occurs if the numbers of target and decoy proteins selected for the second search are not equal. Here, we propose a method of decoy database generation based on the previously reported decoy fusion strategy. This method allows unbiased TDA-based FDR estimation in multi-stage searches and can be easily integrated into existing workflows utilizing popular search engines and post-search algorithms.

  10. Effectiveness of multi-stage scrubbers in reducing emissions of air pollutants from pig houses

    OpenAIRE

    Zhao, Y.; Aarnink, A.J.A.; Jong, de, P.; Ogink, N. W. M.; Groot Koerkamp, P.W.G.

    2011-01-01

    Emissions of air pollutants from livestock houses may raise environmental problems and pose hazards to public health. They can be reduced by scrubbers installed at the air outlets of livestock houses. In this study, three multi-stage scrubbers were evaluated in terms of their effectiveness in reducing emissions of airborne dust, total bacteria, ammonia, and CO2 from pig houses in winter. The three multi-stage scrubbers were one double-stage scrubber (acid stage+ bio-filter), one double-stage ...

  11. Sequential maneuvering decisions based on multi-stage influence diagram in air combat

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A multi-stage influence diagram is used to model the pilot's sequential decision making in one on one air combat.The model based on the multi-stage influence diagram graphically describes the elements of decision process,and contains a point-mass model for the dynamics of an aircraft and takes into account the decision maker's Dreferences under uncertain conditions.Considering an active opponent,the opponent's maneuvers can be modeled stochastically.The solution of multistage influence diagram Can be obtained by converting the multistage influence diagram into a two-level optimization problem.The simulation results show the model is effective.

  12. Liquefaction of uranium tailings

    International Nuclear Information System (INIS)

    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

  13. 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.

  14. Strain Paths and Fractures in Rotational Symmetric Multi Stage Single Point Incremental Forming

    DEFF Research Database (Denmark)

    Skjødt, Martin; Silva, M.B.; Martins, P.A.F.;

    2008-01-01

    A multi stage strategy, which allows forming of SPIF parts with vertical walls, is investigated with emphasis on strain paths and fracture strains. Whereas downwards movement of the tool pin results in deformation close to plane strain upwards moving tool results in biaxial strains. A good correl...

  15. Thickness distribution of multi-stage incremental forming with different forming stages and angle intervals

    Institute of Scientific and Technical Information of China (English)

    李军超; 杨芬芬; 周志强

    2015-01-01

    Although multi-stage incremental sheet forming has always been adopted instead of single-stage forming to form parts with a steep wall angle or to achieve a high forming performance, it is largely dependent on empirical designs. In order to research multi-stage forming further, the effect of forming stages (n) and angle interval between the two adjacent stages (Δα) on thickness distribution was investigated. Firstly, a finite element method (FEM) model of multi-stage incremental forming was established and experimentally verified. Then, based on the proposed simulation model, different strategies were adopted to form a frustum of cone with wall angle of 30° to research the thickness distribution of multi-pass forming. It is proved that the minimum thickness increases largely and the variance of sheet thickness decreases significantly as the value of n grows. Further, with the increase of Δα, the minimum thickness increases initially and then decreases, and the optimal thickness distribution is achieved with Δα of 10°. Additionally, a formula is deduced to estimate the sheet thickness after multi-stage forming and proved to be effective. And the simulation results fit well with the experimental results.

  16. Effectiveness of multi-stage scrubbers in reducing emissions of air pollutants from pig houses

    NARCIS (Netherlands)

    Zhao, Y.; Aarnink, A.J.A.; Jong, de M.C.M.; Ogink, N.W.M.; Groot Koerkamp, P.W.G.

    2011-01-01

    Emissions of air pollutants from livestock houses may raise environmental problems and pose hazards to public health. They can be reduced by scrubbers installed at the air outlets of livestock houses. In this study, three multi-stage scrubbers were evaluated in terms of their effectiveness in reduci

  17. Multi-stage kernel-based conditional quantile prediction in time series

    NARCIS (Netherlands)

    J.G. de Gooijer; A. Gannoun; D. Zerom Godefay

    2001-01-01

    We present a multi-stage conditional quantile predictor for time series of Markovian structure. It is proved that at any quantile level p \\in (0,1), the asymptotic mean squared error (MSE) of the new predictor is smaller than the single-stage conditional quantile predictor. A simulation study confir

  18. Axial liquid mixing in a gas-liquid Multi-Stage Agitated Contactor (MAC)

    NARCIS (Netherlands)

    Breman, B.B; Beenackers, A.A C M; Bouma, M.J; VanderWerf, M.H.

    1996-01-01

    Data on interstage liquid mixing are reported for a gas-liquid Multi-stage Agitated Contactor (MAC). A dynamic method using heat as a tracer was applied for water, n-octane and monoethylene glycol as liquids both with and without the presence of a dispersed gas phase (air). In all cases, the axial m

  19. Seven prostate cancer susceptibility loci identified by a multi-stage genome-wide association study

    DEFF Research Database (Denmark)

    Kote-Jarai, Zsofia; Olama, Ali Amin Al; Giles, Graham G;

    2011-01-01

    Prostate cancer (PrCa) is the most frequently diagnosed male cancer in developed countries. We conducted a multi-stage genome-wide association study for PrCa and previously reported the results of the first two stages, which identified 16 PrCa susceptibility loci. We report here the results...

  20. Seven prostate cancer susceptibility loci identified by a multi-stage genome-wide association study

    DEFF Research Database (Denmark)

    Kote-Jarai, Zsofia; Olama, Ali Amin Al; Giles, Graham G;

    2011-01-01

    Prostate cancer (PrCa) is the most frequently diagnosed male cancer in developed countries. We conducted a multi-stage genome-wide association study for PrCa and previously reported the results of the first two stages, which identified 16 PrCa susceptibility loci. We report here the results of st...

  1. Research on EMI Reduction of Multi-stage Interleaved Bridgeless Power Factor Corrector

    DEFF Research Database (Denmark)

    Li, Qingnan; Thomsen, Ole Cornelius; Andersen, Michael A. E.

    2012-01-01

    Working as an electronic pollution eliminator, the Power Factor Corrector's (PFC) own Electromagnetic Interference (EMI) problems have been blocking its performance improvement for long. In this paper, a systematic research on EMI generation of a multi-stage Two-Boost-Circuit Interleaved Bridgeless...

  2. Co-liquefaction of the Elbistan Lignite and Poplar Sawdust. Part I: The Effect of the Liquefaction Parameters

    Energy Technology Data Exchange (ETDEWEB)

    Karaca, H.; Acar, M.; Yilmaz, M.; Keklik, I. [Inonu University, Malatya (Turkey). Faculty of Engineering

    2009-07-01

    In this study, the liquefaction of Elbistan lignite and poplar sawdust, and the co-liquefaction of the Elbistan lignite and the poplar sawdust in an inert atmosphere and in non-catalytic conditions have been examined. Also, the effects of solvent/coal ratio and stirring speed on the total conversion derived as the result of the liquefaction process was attempted to be determined. Based on the results, although the effects of the solvent/coal ratio and the stirring speed on total conversion are similar for both the Elbistan lignite and the poplar sawdust, it was also noted that, under similar conditions, the conversion for the poplar sawdust was higher, as compared to the conversion of the Elbistan lignite. As the result of the liquefaction of Elbistan lignite and poplar sawdust under inert atmospheric conditions, the total conversion was increased partially, depending on both solvent/coal ratio and the speed of stirring. However, it was also noted that the total conversion did not change to a significant extent in high solvent/coal ratios and in stirring speed. As the result of the co-liquefaction of the Elbistan lignite and poplar sawdust under inert atmospheric conditions, total conversion was increased, based on the solvent/coal ratio. However, as in the case of the liquefaction of Elbistan lignite and poplar sawdust, it was noted that the high solvent/coal ratios (i.e., solvent/coal ratios of higher than 2/1) did not have a significant effect on the total conversion that was derived as the result of the co-liquefaction of the Elbistan lignite and poplar sawdust.

  3. 亚/超临界甲醇体系中磷钼酸催化液化木粉%Catalytic liquefaction of wood in sub/supercritical methanol under phosphomolybdic acid

    Institute of Scientific and Technical Information of China (English)

    曾常伟; 林星; 汪雪琴; 蔡政汉; 吕建华; 黄彪

    2016-01-01

    To discover bio-environmental and sustainable catalyst to effectively transform fir sawdust to biofuel, liquefaction process catalyzed by phosphomolybdic acid and using sub/supercritical methanol as solvent was evaluated. The optimum reaction condition was investigated in terms of temperature, duration, dosages of catalyst and sawdust. Results showed that phosphomolybdic acid to-gether with subcritical methanol significantly accelerated sawdust liquefaction. The optimum reaction condition was achieved at liquif-ying 1 g sawdust, 150 mL methanol and 0.5 g phosphomolybdic acid at 240℃ for 30 minutes, maximizing at 93.32%. Subsequent-ly, quantity and chemical composition of light bio-oil, heavy bio-oil and residue were characterized by scanning electron microscope, Fourier translation infrared spectrum and gas chromatography-mass spectrometer. Results showed that the residue was mainly consist of lignin and its derivatives, which was from the liquefaction of lignin from methanol. Light bio-oil obtained at optimum condition comprised of complex compounds such as ester, phenol, aldehyde and ketone, resulting from the reaction between cellulose and methanol. While, heavy bio-oil, mainly comprised of phenol, was obtained from lignin liquefaction.%以杉木屑为原料,研究磷钼酸在亚/超临界甲醇条件下的催化液化性能,并探讨反应温度、反应时间、催化剂用量和杉木屑用量对杉木屑液化率的影响.结果表明该磷钼酸在亚/超临界甲醇条件下具有很好的催化液化性能.在150 mL甲醇、0.5 g催化剂、1 g杉木屑、240℃条件下反应30 min,液化率达到93.32%.采用SEM、FT-IR和GC-MS对液化残渣、轻油和重油进行表征.结果表明,残渣主要是由木质素或木质素衍生物组成;而液化产物轻油主要是由酯类、酚类、醛类、酮类等组成,主要是由纤维素及半纤维素与甲醇反应得到;而液化产物重油中的酚类物质主要是由木质素液化反应得到.

  4. Magnetic refrigerator for hydrogen liquefaction

    OpenAIRE

    Matsumoto, Koichi; Kondo, T.; Yoshioka, S; Kamiya, K.; Numazawa, T.

    2009-01-01

    Magnetic refrigeration which is based on the magnetocaloric effect of solids has the potential to achieve high thermal efficiency for hydrogen liquefaction. We have been developing a magnetic refrigerator for hydrogen liquefaction which cools down hydrogen gas from liquid natural gas temperature and liquefies at 20 K. The magnetic liquefaction system consists of two magnetic refrigerators: Carnot magnetic refrigerator (CMR) and active magnetic regenerator (AMR) device. CMR with Carnot cycle s...

  5. Mechanical and mathematical models of multi-stage horizontal fracturing strings and their application

    Directory of Open Access Journals (Sweden)

    Zhanghua Lian

    2015-03-01

    Full Text Available Multi-stage SRV fracturing in horizontal wells is a new technology developed at home and abroad in recent years to effectively develop shale gas or low-permeability reservoirs, but on the other hand makes the mechanical environment of fracturing strings more complicated at the same time. In view of this, based on the loading features of tubing strings during the multi-stage fracturing of a horizontal well, mechanical models were established for three working cases of multiple packer setting, open differential-pressure sliding sleeve, and open ball-injection sliding sleeve under a hold-down packer. Moreover, mathematical models were respectively built for the above three cases. According to the Lame formula and Von Mises stress calculation formula for the thick-walled cylinder in the theory of elastic mechanics, a mathematical model was also established to calculate the equivalent stress for tubing string safety evaluation when the fracturing string was under the combined action of inner pressure, external squeezing force and axial stress, and another mathematical model was built for the mechanical strength and safety evaluation of multi-stage fracturing strings. In addition, a practical software was developed for the mechanical safety evaluation of horizontal well multi-stage fracturing strings according to the mathematical model developed for the mechanical calculation of the multi-packer string in horizontal wells. The research results were applied and verified in a gas well of Tahe Oilfield in the Tarim Basin with excellent effects, providing a theoretical basis and a simple and reliable technical means for optimal design and safety evaluation of safe operational parameters of multi-stage fracturing strings in horizontal wells.

  6. The natural gas liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Petit, P.

    1996-03-01

    This work deals with the transport of natural gas and more particularly with the natural gas liquefaction. Indeed, the transport distances (several thousands of kilometers) and the existing seaways have incited to develop a marine transport chain: the liquefied natural gas is carried out at - 161 degrees Celsius in thermically isolated containers of methane tankers. The interest of liquefying the natural gas is that it allows to reduce a lot the storage containers (650 m{sup 3} of gas at the atmospheric pressure only gives 1 m{sup 3} at the liquid state). In this study, the main constituents of the natural gas are given. The different liquefaction plants which exist in the world are described. Two units types exist at present: the base load and the peak shaving units. The liquefaction processes are then explained (the Pictet cycles, the auto-refrigerated cascade cycle and the combined cycles). The liquid obtained from natural gas has then to be re-gasified before being distributed. The re-gasification processes are then given. The heat exchangers used in liquefaction or re-gasification plants equipment are cryogenic exchangers: they can run with very weak temperature variations and on a very large temperature range. They are compared into details. The important quantities of the cryogenic liquid that constitutes the natural gas liquid contain a considerable energetic potential. In order to recover this energy, several solutions have been elaborated, for instance in using as cold source the natural gas liquid under re-gasification. A cost estimation of a natural gas plant is given too. (O.M.). 18 figs., 7 tabs.

  7. Organosolv liquefaction of sugarcane bagasse catalyzed by acidic ionic liquids.

    Science.gov (United States)

    Chen, Zhengjian; Long, Jinxing

    2016-08-01

    An efficient and eco-friendly process is proposed for sugarcane bagasse liquefaction under mild condition using IL catalyst and environmental friendly solvent of ethanol/H2O. The relationship between IL acidic strength and its catalytic performance is investigated. The effects of reaction condition parameters such as catalyst dosage, temperature, time and solvent are also intensively studied. The results show that ethanol/H2O has a significant promotion effect on the simultaneous liquefaction of sugarcane bagasse carbohydrate and lignin. 97.5% of the bagasse can be liquefied with 66.46% of volatile product yield at 200°C for 30min. Furthermore, the IL catalyst shows good recyclability where no significant loss of the catalytic activity is exhibited even after five runs. PMID:27115746

  8. Examination of alternative catalysts for biomass direct liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Tran, A.D.; Rogers, D.Z.

    1985-08-01

    We have now completed a survey study of several water-soluble salts of transition metals that are deemed likely to have utility as catalysts for direct biomass liquefaction in a carbon monoxide steam process. Certain salts of molybdenum and nickel are the most effective catalysts, and are the only species for which some catalytic activity independent of the ligand can be shown. The most effective forms of the nickel and molybdenum are cyanide and oxyanion complexes. 30 refs., 5 figs., 4 tabs.

  9. 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.

  10. 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...... wave height. Recommendations are made as to how to assess liquefaction potential in standing waves. Copyright © 2012 by the International Society of Offshore and Polar Engineers (ISOPE)....

  11. Pricing convertible bonds based on a multi-stage compound-option model

    Science.gov (United States)

    Gong, Pu; He, Zhiwei; Zhu, Song-Ping

    2006-07-01

    In this paper, we introduce the concept of multi-stage compound options to the valuation of convertible bonds (CBs). Rather than evaluating a nested high-dimensional integral that has arisen from the valuation of multi-stage compound options, we found that adopting the finite difference method (FDM) to solve the Black-Scholes equation for each stage actually resulted in a better numerical efficiency. By comparing our results with those obtained by solving the Black-Scholes equation directly, we can show that the new approach does provide an approximation approach for the valuation of CBs and demonstrate that it offers a great potential for a further extension to CBs with more complex structures such as those with call and/or put provisions.

  12. Multi-stage high order semi-Lagrangian schemes for incompressible flows in Cartesian geometries

    CERN Document Server

    Cameron, Alexandre; Dormy, Emmanuel

    2016-01-01

    Efficient transport algorithms are essential to the numerical resolution of incompressible fluid flow problems. Semi-Lagrangian methods are widely used in grid based methods to achieve this aim. The accuracy of the interpolation strategy then determines the properties of the scheme. We introduce a simple multi-stage procedure which can easily be used to increase the order of accuracy of a code based on multi-linear interpolations. This approach is an extension of a corrective algorithm introduced by Dupont \\& Liu (2003, 2007). This multi-stage procedure can be easily implemented in existing parallel codes using a domain decomposition strategy, as the communications pattern is identical to that of the multi-linear scheme. We show how a combination of a forward and backward error correction can provide a third-order accurate scheme, thus significantly reducing diffusive effects while retaining a non-dispersive leading error term.

  13. A 1 kW-class multi-stage heat-driven thermoacoustic cryocooler system operating at liquefied natural gas temperature range

    Science.gov (United States)

    Zhang, L. M.; Hu, J. Y.; Wu, Z. H.; Luo, E. C.; Xu, J. Y.; Bi, T. J.

    2015-07-01

    This article introduces a multi-stage heat-driven thermoacoustic cryocooler capable of reaching cooling capacity about 1 kW at liquefied natural gas temperature range without any moving mechanical parts. The cooling system consists of an acoustically resonant double-acing traveling wave thermoacoustic heat engine and three identical pulse tube coolers. Unlike other traditional traveling wave thermoacoustic heat engines, the acoustically resonant double-acting thermoacoustic heat engine is a closed-loop configuration consists of three identical thermoacoustic conversion units. Each pulse tube cooler is bypass driven by one thermoacoustic heat engine unit. The device is acoustically completely symmetric and therefore "self-matching" for efficient traveling-wave thermoacoustic conversion. In the experiments, with 7 MPa helium gas as working gas, when the heating temperature reaches 918 K, total cooling capacity of 0.88 kW at 110 K is obtained with a resonant frequency of about 55 Hz. When the heating temperature is 903 K, a maximum total cooling capacity at 130 K of 1.20 kW is achieved, with a thermal-to-cold exergy efficiency of 8%. Compared to previously developed heat-driven thermoacoustic cryocoolers, this device has higher thermal efficiency and higher power density. It shows a good prospect of application in the field of natural gas liquefaction and recondensation.

  14. Flash flood detection through a multi-stage probabilistic warning system for heavy precipitation events

    OpenAIRE

    Alfieri, L.; Velasco, D.; Thielen, J.

    2011-01-01

    The deadly combination of short to no warning lead times and the vulnerability of urbanized areas makes flash flood events extremely dangerous for the modern society. This paper contributes to flash flood early warning by proposing a multi-stage warning system for heavy precipitation events based on threshold exceedances within a probabilistic framework. It makes use of meteorological products at different resolutions, namely, numerical weather predictions (NWP), radar-NWP b...

  15. An integrated multi-stage supply chain inventory model with imperfect production process

    OpenAIRE

    Soumita Kundu; Tripti Chakrabarti

    2015-01-01

    This paper deals with an integrated multi-stage supply chain inventory model with the objective of cost minimization by synchronizing the replenishment decisions for procurement, production and delivery activities. The supply chain structure examined here consists of a single manufacturer with multi-buyer where manufacturer orders a fixed quantity of raw material from outside suppliers, processes the materials and delivers the finished products in unequal shipments to each customer. In this p...

  16. Multi-stage phase retrieval algorithm based upon the gyrator transform

    OpenAIRE

    Rodrigo, José A.; Duadi, H.; Alieva, Tatiana; Zalevsky, Z.

    2010-01-01

    The gyrator transform is a useful tool for optical information processing applications. In this work we propose a multi-stage phase retrieval approach based on this operation as well as on the well-known Gerchberg-Saxton algorithm. It results in an iterative algorithm able to retrieve the phase information using several measurements of the gyrator transform power spectrum. The viability and performance of the proposed algorithm is demonstrated by means of several numerical simulations and exp...

  17. Application of multi-stage Monte Carlo method for solving machining optimization problems

    Directory of Open Access Journals (Sweden)

    Miloš Madić

    2014-08-01

    Full Text Available Enhancing the overall machining performance implies optimization of machining processes, i.e. determination of optimal machining parameters combination. Optimization of machining processes is an active field of research where different optimization methods are being used to determine an optimal combination of different machining parameters. In this paper, multi-stage Monte Carlo (MC method was employed to determine optimal combinations of machining parameters for six machining processes, i.e. drilling, turning, turn-milling, abrasive waterjet machining, electrochemical discharge machining and electrochemical micromachining. Optimization solutions obtained by using multi-stage MC method were compared with the optimization solutions of past researchers obtained by using meta-heuristic optimization methods, e.g. genetic algorithm, simulated annealing algorithm, artificial bee colony algorithm and teaching learning based optimization algorithm. The obtained results prove the applicability and suitability of the multi-stage MC method for solving machining optimization problems with up to four independent variables. Specific features, merits and drawbacks of the MC method were also discussed.

  18. Algae liquefaction / Hope Baloyi

    OpenAIRE

    Baloyi, Hope

    2012-01-01

    The liquefaction of algae for the recovery of bio–oil was studied. Algae oil is a non–edible feedstock and has minimal impact on food security and food prices; furthermore, it has been identified as a favourable feedstock for the production of biodiesel and this is attributed to its high oil yield per hectare. Algae oil can be potentially used for fuel blending for conventional diesel. The recovery step for algae oil for the production of biodiesel is costly and demands a lot of energy due to...

  19. Hydrotreating of distillates from Spanish coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-02-01

    Distillates obtained from a first-stage Spanish coal liquefaction process have been catalytically hydrotreated in microreactor in two steps. A commercially available Harshaw HT-400 E (Co-Mo/Al[sub 2]O[sub 3]) catalyst, 10 MPa hydrogen pressure and two temperatures (400 and 425deg C) have been used. The results have been evaluated for heteroatoms removal, oils yield, boiling point distribution and aromaticity by several techniques (GC, FT-i.r., [sup 1]H n.m.r., ultrasonic extraction and liquid chromatography). At the first step of hydrotreating, preasphaltenes rather than asphaltenes have been hydrocracked to produce smaller-size polar compounds in the oil fraction but aromaticity has not varied significatively. In the second step, heteroatoms content have been considerably reduced and the product meets refinery specifications for nitrogen but does not meet sulphur refinery specifications for feedstocks. (orig.).

  20. 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....

  1. Mathematical modeling on multi-stage series crushing ratio distribution based on fuzzy physical programming

    Institute of Scientific and Technical Information of China (English)

    Yu-Long QI; Chen-Chen CAI; Ping-Zhen LANG

    2013-01-01

    Double-layer,multi-roller plate crusher is a new device,that uses a multi-stage series crushing style to break particles,with the crushing ratio distribution directly influencing the machine's performance.Three crushing ratios of 2.25,2.15 and 2.0 1,used for fuzzy physical programming,were determined.The comparison of the optimized result between the double-layer multi-roller plate crusher and a high pressure roll grinder showed that the double-layer multi-roller plate crusher had a better performance,reducing crushing force and wear.

  2. Multi Stage Strategies for Single Point Incremental Forming of a Cup

    DEFF Research Database (Denmark)

    Skjødt, Martin; Bay, Niels; Endelt, Benny;

    2008-01-01

    comparing explicit FE analysis with experiments. Good agreement is found between calculated and measured thickness distribution, overall geometry and strains. Using the proposed multi stage strategy it is shown possible to produce a cup with a height close to the radius and side parallel to the symmetry......A five stage forming strategy for forming of a circular cylindrical cup with a height/radius ratio of one is presented. Geometrical relations are discussed and theoretical strains are calculated. The influence of forming direction (upwards or downwards) is investigated for the second stage...

  3. Reduction of multi-stage disk models: Application to an industrial rotor

    OpenAIRE

    Sternchüss, Arnaud,; Balmes, Etienne; Jean, Pierrick; Lombard, Jean Pierre

    2009-01-01

    The present study deals with the reduction of models of multi-stage bladed disk assemblies. The proposed method relies on the substructuring of the rotor into sectors. The bladed disks are coupled by intermediate rings which remove the problem of incompatible meshes. The sectors are represented by super-elements whose kinematic subspaces are spanned by a set of cyclic modeshapes and a set of normal modes when their left and right interfaces are fixed. The first step is to compute the cyclic m...

  4. A theoretical analysis of price elasticity of energy demand in multi-stage energy conversion systems

    International Nuclear Information System (INIS)

    The objective of this paper is an analytical exploration of the problem of price elasticity of energy demand in multi-stage energy conversion systems. The paper describes in some detail an analytical model of energy demand in such systems. Under a clearly stated set of assumptions, the model makes it possible to explore both the impacts of the number of sub-systems, and of varying sub-system elasticities on overall system elasticity. The analysis suggests that overall price elasticity of energy demand for such systems will tend asymptotically to unity as the number of sub-systems increases

  5. A theoretical analysis of price elasticity of energy demand in multi-stage energy conversion systems

    OpenAIRE

    Lowe, R J

    2003-01-01

    The objective of this paper is an analytical exploration of the problem of price elasticity of energy demand in multi-stage energy conversion systems. The paper describes in some detail an analytical model of energy demand in such systems. Under a clearly stated set of assumptions, the model makes it possible to explore both the impacts of the number of sub-systems, and of varying sub-system elasticities on overall system elasticity. The analysis suggests that overall price elasticity of ener...

  6. Oscillating Disturbance Propagation in Passages of Multi-Stage Hydrogen Turbine

    Institute of Scientific and Technical Information of China (English)

    刘红; 郑晓琳; 陈佐一

    2001-01-01

    The propagation of oscillating disturbances with various frequencies in multi-stage turbine passages in a rocket is analyzed using the oscillating fluid mechanics theorem and the parametric polynomial method. The results show that oscillating disturbances can be rapidly dissipated when the disturbance occurs at the inlet except for very high-frequency oscillation such as 50 kHz. Dangerous low-frequency oscillations occur at the outlet. The effects of the flow parameter variations on the oscillating disturbance propagation are also studied. The analysis will facilitate safe operation of the whole rocket system.

  7. Lab-testing, predicting, and modeling multi-stage activated carbon adsorption of organic micro-pollutants from treated wastewater.

    Science.gov (United States)

    Zietzschmann, F; Altmann, J; Hannemann, C; Jekel, M

    2015-10-15

    Multi-stage reuse of powdered activated carbon (PAC) is often applied in practice for a more efficient exploitation of the PAC capacity to remove organic micro-pollutants (OMP). However, the adsorption mechanisms in multi-stage PAC reuse are rarely investigated, as large-scale experiments do not allow for systematic tests. In this study, a laboratory method for the separation of PAC/water suspensions and the subsequent reuse of the PAC and the water was developed. The method was tested on wastewater treatment plant (WWTP) effluent in a setup with up to 7 PAC reuse stages. The tests show that the overall OMP removal from WWTP effluent can be increased when reusing PAC. The reason is that a repeated adsorption in multi-stage PAC reuse results in similar equilibrium concentrations as a single-stage adsorption. Thus, a single relationship between solid and liquid phase OMP concentrations appears valid throughout all stages. This also means that the adsorption efficiency of multi-stage PAC reuse setups can be estimated from the data of a single-stage setup. Furthermore, the overall OMP removals in multi-stage setups coincide with the overall UV254 removals, and for each respective OMP one relationship to UV254 removal is valid throughout all stages. The results were modeled by a simple modification of the equivalent background compound model (EBCM) which was also used to simulate the additional OMP removals in multi-stage setups with up to 50 reuse stages. PMID:26117373

  8. Magnetic refrigerator for hydrogen liquefaction

    International Nuclear Information System (INIS)

    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.

  9. Purification of High Salinity Brine by Multi-Stage Ion Concentration Polarization Desalination

    Science.gov (United States)

    Kim, Bumjoo; Kwak, Rhokyun; Kwon, Hyukjin J.; Pham, Van Sang; Kim, Minseok; Al-Anzi, Bader; Lim, Geunbae; Han, Jongyoon

    2016-01-01

    There is an increasing need for the desalination of high concentration brine (>TDS 35,000 ppm) efficiently and economically, either for the treatment of produced water from shale gas/oil development, or minimizing the environmental impact of brine from existing desalination plants. Yet, reverse osmosis (RO), which is the most widely used for desalination currently, is not practical for brine desalination. This paper demonstrates technical and economic feasibility of ICP (Ion Concentration Polarization) electrical desalination for the high saline water treatment, by adopting multi-stage operation with better energy efficiency. Optimized multi-staging configurations, dependent on the brine salinity values, can be designed based on experimental and numerical analysis. Such an optimization aims at achieving not just the energy efficiency but also (membrane) area efficiency, lowering the true cost of brine treatment. ICP electrical desalination is shown here to treat brine salinity up to 100,000 ppm of Total Dissolved Solids (TDS) with flexible salt rejection rate up to 70% which is promising in a various application treating brine waste. We also demonstrate that ICP desalination has advantage of removing both salts and diverse suspended solids simultaneously, and less susceptibility to membrane fouling/scaling, which is a significant challenge in the membrane processes. PMID:27545955

  10. Multi-stage ponds-wetlands ecosystem for effective wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    PENG Jian-feng; WANG Bao-zhen; WANG Lin

    2005-01-01

    The performance of the Dongying multi-stage ponds-wetlands ecosystem was investigated in this work. Study of the removal of different pollutants (BOD5, COD, SS, TP, TN, NH3-N, etc.) in different temperature seasons and different units in this system indicated that effluent BOD5 and SS were constant to less than 11 mg/L and 14 mg/L throughout the experimental processes; but that the removal efficiencies of pollutants such as TP, TN, NH3-N, COD varied greatly with season. The higher the temperature was, the higher was the observed removal in this system. Additionally, each unit of the system functioned differently in removing pollutants. BOD5 and SS were mainly removed in the first three units (hybrid facultative ponds, aeration ponds and aerated fish ponds), whereas nitrogen and phosphates were mainly removed in hydrophyte ponds and constructed reed wetlands.The multi-stage ponds-wetlands ecosystem exhibits good potential of removing different pollutants, and the effluent quality meet several standards for wastewater reuse.

  11. Multi-stage shifter for subsecond time resolution of emulsion gamma-ray telescopes

    Science.gov (United States)

    Rokujo, H.; Aoki, S.; Takahashi, S.; Kamada, K.; Mizutani, S.; Nakagawa, R.; Ozaki, K.

    2013-02-01

    To observe gamma-ray sources precisely, a balloon-borne experiment with a new type of detector, the emulsion gamma-ray telescope, is planned. A multi-stage shifter mechanism based on the concept of an analog clock serves as a time stamper with subsecond time resolution and uses multiple moving stages mounted on the emulsion chambers. This new technique was employed in a test experiment using a small-scale model in a short-duration balloon flight. Tracks recorded in nuclear emulsion were read by a fully automated scanning system, were reconstructed, and time information were assigned by analysis of their position displacements in the shifter layers. The estimated time resolution was 0.06-0.15 s. The number of tracks passing through the detector was counted every second, and hadron jets were detected as significant excesses observed in the counting rate. In future, the multi-stage shifter is greatly contributing to ongoing efforts to increase the effective area of emulsion gamma-ray telescopes.

  12. Simulation and analysis of multi-stage centrifugal fractional extraction process of 4-nitrobenzene glycine enantiomers☆

    Institute of Scientific and Technical Information of China (English)

    Ping Wen; Kewen Tang; Jicheng Zhou; Panliang Zhang

    2015-01-01

    Based on the interfacial ligand exchange model and the law of conservation of mass, the multi-stage enantioselective liquid–liquid extraction model has been established to analyze and discuss on multi-stage centrifugal fractional extraction process of 4-nitrobenzene glycine (PGL) enantiomers. The influence of phase ratio, extractant concentra-tion, and PF6−concentration on the concentrations of enantiomers in the extract and raffinate was investigated by experiment and simulation. A good agreement between model and experiment was obtained. On this basis, the influence of many parameters such as location of stage, concentration levels, extractant excess, and number of stages on the symmetric separation performance was simulated. The optimal location of feed stage is the middle of fractional extraction equipment. The feed flow must satisfy a restricted relationship on flow ratios and the liquid throughout of centrifugal device. For desired purity specification, the required flow ratios decrease with extractant concentration and increase with PF6−concentration. When the number of stages is 18 stages at extractant excess of 1.0 or 14 stages at extractant excess of 2.0, the eeeq (equal enantiomeric excess) can reach to 99%.

  13. Modelling and Control of the Multi-stage Cable Pulley-driven Flexible-joint Robot

    Directory of Open Access Journals (Sweden)

    Phongsaen Pitakwatchara

    2014-07-01

    Full Text Available This work is concerned with the task space impedance control of a robot driven through a multi-stage nonlinear flexible transmission system. Specifically, a two degrees-of-freedom cable pulley-driven flexible-joint robot is considered. Realistic modelling of the system is developed within the bond graph modelling framework. The model captures the nonlinear compliance behaviour of the multi-stage cable pulley transmission system, the spring effect of the augmented counterbalancing mechanism, the major loss throughout the system elements, and the typical inertial dynamics of the robot. Next, a task space impedance controller based on limited information about the angle and the current of the motors is designed. The motor current is used to infer the transmitted torque, by which the motor inertia may be modulated. The motor angle is employed to estimate the stationary distal robot link angle and the robot joint velocity. They are used in the controller to generate the desired damping force and to shape the potential energy of the flexible joint robot system to the desired configuration. Simulation and experimental results of the controlled system signify the competency of the proposed control law.

  14. Purification of High Salinity Brine by Multi-Stage Ion Concentration Polarization Desalination

    Science.gov (United States)

    Kim, Bumjoo; Kwak, Rhokyun; Kwon, Hyukjin J.; Pham, Van Sang; Kim, Minseok; Al-Anzi, Bader; Lim, Geunbae; Han, Jongyoon

    2016-08-01

    There is an increasing need for the desalination of high concentration brine (>TDS 35,000 ppm) efficiently and economically, either for the treatment of produced water from shale gas/oil development, or minimizing the environmental impact of brine from existing desalination plants. Yet, reverse osmosis (RO), which is the most widely used for desalination currently, is not practical for brine desalination. This paper demonstrates technical and economic feasibility of ICP (Ion Concentration Polarization) electrical desalination for the high saline water treatment, by adopting multi-stage operation with better energy efficiency. Optimized multi-staging configurations, dependent on the brine salinity values, can be designed based on experimental and numerical analysis. Such an optimization aims at achieving not just the energy efficiency but also (membrane) area efficiency, lowering the true cost of brine treatment. ICP electrical desalination is shown here to treat brine salinity up to 100,000 ppm of Total Dissolved Solids (TDS) with flexible salt rejection rate up to 70% which is promising in a various application treating brine waste. We also demonstrate that ICP desalination has advantage of removing both salts and diverse suspended solids simultaneously, and less susceptibility to membrane fouling/scaling, which is a significant challenge in the membrane processes.

  15. Purification of High Salinity Brine by Multi-Stage Ion Concentration Polarization Desalination.

    Science.gov (United States)

    Kim, Bumjoo; Kwak, Rhokyun; Kwon, Hyukjin J; Pham, Van Sang; Kim, Minseok; Al-Anzi, Bader; Lim, Geunbae; Han, Jongyoon

    2016-01-01

    There is an increasing need for the desalination of high concentration brine (>TDS 35,000 ppm) efficiently and economically, either for the treatment of produced water from shale gas/oil development, or minimizing the environmental impact of brine from existing desalination plants. Yet, reverse osmosis (RO), which is the most widely used for desalination currently, is not practical for brine desalination. This paper demonstrates technical and economic feasibility of ICP (Ion Concentration Polarization) electrical desalination for the high saline water treatment, by adopting multi-stage operation with better energy efficiency. Optimized multi-staging configurations, dependent on the brine salinity values, can be designed based on experimental and numerical analysis. Such an optimization aims at achieving not just the energy efficiency but also (membrane) area efficiency, lowering the true cost of brine treatment. ICP electrical desalination is shown here to treat brine salinity up to 100,000 ppm of Total Dissolved Solids (TDS) with flexible salt rejection rate up to 70% which is promising in a various application treating brine waste. We also demonstrate that ICP desalination has advantage of removing both salts and diverse suspended solids simultaneously, and less susceptibility to membrane fouling/scaling, which is a significant challenge in the membrane processes. PMID:27545955

  16. Distribution characteristics of holdups in a multi-stage bubble column using electrical resistance tomography

    Institute of Scientific and Technical Information of China (English)

    Haibo Jin; Yicheng Lian; Yujian Qin; Suohe Yang; Guangxiang He

    2013-01-01

    Based on the principle of chemical reaction engineering,the addition of perforated plates can improve the performance of conventional bubble column and decrease the backmixing behaviors.The distribution characteristics of gas holdup in a multi-stage bubble column embedded with five types of sieve plates and three types of tongue plates were studied using electrical resistance tomography (ERT).The effects of superficial gas velocity and the geometric design of perforated plates on the gas holdup and its radial distribution above and below the plates of the bubble column were discussed.Experimental results show ERT is suitable as an online monitoring tool to provide useful information on the hydrodynamic parameters of multi-stage bubble columns.With increasing superficial gas velocity,local gas holdup increases,and gas holdup below the plate increases with decrease of free area (%FA),hole diameters or angle of tongue plates.ERT technique facilitates noninvasive and nonintrusive visualization of cross-sectional distribution of gas holdup in a bubble column.

  17. Young adults' decision making surrounding heavy drinking: a multi-staged model of planned behaviour.

    Science.gov (United States)

    Northcote, Jeremy

    2011-06-01

    This paper examines the real life contexts in which decisions surrounding heavy drinking are made by young adults (that is, on occasions when five or more alcoholic drinks are consumed within a few hours). It presents a conceptual model that views such decision making as a multi-faceted and multi-staged process. The mixed method study draws on purposive data gathered through direct observation of eight social networks consisting of 81 young adults aged between 18 and 25 years in Perth, Western Australia, including in-depth interviews with 31 participants. Qualitative and some basic quantitative data were gathered using participant observation and in-depth interviews undertaken over an eighteen month period. Participants explained their decision to engage in heavy drinking as based on a variety of factors. These elements relate to socio-cultural norms and expectancies that are best explained by the theory of planned behaviour. A framework is proposed that characterises heavy drinking as taking place in a multi-staged manner, with young adults having: 1. A generalised orientation to the value of heavy drinking shaped by wider influences and norms; 2. A short-term orientation shaped by situational factors that determines drinking intentions for specific events; and 3. An evaluative orientation shaped by moderating factors. The value of qualitative studies of decision making in real life contexts is advanced to complement the mostly quantitative research that dominates research on alcohol decision making.

  18. Inspection logistics planning for multi-stage production systems with applications to semiconductor fabrication lines

    Science.gov (United States)

    Chen, Kyle Dakai

    Since the market for semiconductor products has become more lucrative and competitive, research into improving yields for semiconductor fabrication lines has lately received a tremendous amount of attention. One of the most critical tasks in achieving such yield improvements is to plan the in-line inspection sampling efficiently so that any potential yield problems can be detected early and eliminated quickly. We formulate a multi-stage inspection planning model based on configurations in actual semiconductor fabrication lines, specifically taking into account both the capacity constraint and the congestion effects at the inspection station. We propose a new mixed First-Come-First-Serve (FCFS) and Last-Come-First-Serve (LCFS) discipline for serving the inspection samples to expedite the detection of potential yield problems. Employing this mixed FCFS and LCFS discipline, we derive approximate expressions for the queueing delays in yield problem detection time and develop near-optimal algorithms to obtain the inspection logistics planning policies. We also investigate the queueing performance with this mixed type of service discipline under different assumptions and configurations. In addition, we conduct numerical tests and generate managerial insights based on input data from actual semiconductor fabrication lines. To the best of our knowledge, this research is novel in developing, for the first time in the literature, near-optimal results for inspection logistics planning in multi-stage production systems with congestion effects explicitly considered.

  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. A motion study of a manipulator for transferring microparts in a multi stage former

    DEFF Research Database (Denmark)

    Mahshid, Rasoul; Hansen, Hans Nørgaard; Hansen, Casper;

    2013-01-01

    together. A motion study of the system gives an overview of different steps and movements inside the multi stage former. Significantly, increasing the production rate increases the acceleration and also causes the time frame tight. The time limitations put overlaps on the moving parts in terms of...... milliseconds. A high speed camera was used in the experiments with high resolution to show the details of the motion while enabling to detect any unwanted movement within milliseconds. Importantly, increasing the frequency of image capturing within the movement is another beneficial feature in the high speed...... works very well at a real process implementation. This significantly approves the techniques already were given to evaluate the precision in the positioning unit and the gripping unit. Copyright © 2013 by ASME....

  1. Decomposition and (importance) sampling techniques for multi-stage stochastic linear programs

    Energy Technology Data Exchange (ETDEWEB)

    Infanger, G.

    1993-11-01

    The difficulty of solving large-scale multi-stage stochastic linear programs arises from the sheer number of scenarios associated with numerous stochastic parameters. The number of scenarios grows exponentially with the number of stages and problems get easily out of hand even for very moderate numbers of stochastic parameters per stage. Our method combines dual (Benders) decomposition with Monte Carlo sampling techniques. We employ importance sampling to efficiently obtain accurate estimates of both expected future costs and gradients and right-hand sides of cuts. The method enables us to solve practical large-scale problems with many stages and numerous stochastic parameters per stage. We discuss the theory of sharing and adjusting cuts between different scenarios in a stage. We derive probabilistic lower and upper bounds, where we use importance path sampling for the upper bound estimation. Initial numerical results turned out to be promising.

  2. Multi-Stage Admission Control for Load Balancing in Next Generation Systems

    DEFF Research Database (Denmark)

    Mihovska, Albena D.; Anggorojati, Bayu; Luo, Jijun;

    2008-01-01

    This paper describes a load-dependent multi-stage admission control suitable for next generation systems. The concept uses decision polling in entities located at different levels of the architecture hierarchy and based on the load to activate a sequence of actions related to the admission...... of a user to the network, i.e., the ranking of the intermediate decisions is dynamic. The decision is controlled by passing a token between the base station (BS) and the gateway (GW), thereby considering the load status of the BS and the backhaul network. A token is assigned to the entity with the highest...... load. Each admission request will issue a flag whose colour will reflect the load level in this entity and will determine the correct sequence of the required admission control actions....

  3. Numerical investigation of flow through vegetated multi-stage compound cha-nnel

    Institute of Scientific and Technical Information of China (English)

    王雯; 槐文信; 高猛

    2014-01-01

    This paper addresses the problem of the renormalization group k-e turbulence modeling of a vegetated multi-stage compound channel. Results from Micro acoustic Doppler velocimeter (ADV) tests are used with time and spatial averaging (double-averaging method) in the analysis of the flow field and the characterization. Comparisons of the mean velocity, the Reynolds stress, and the turbulent energy distribution show the validity of the computational method. The mean velocity profile sees an obvious de-celeration in the terraces because of vegetation. Secondary flow exists mainly at the junction of the main channel and the vegetation region on the first terrace. The bed shear stress in the main channel is much greater than that in the terraces. The difference of the bed shear stress between two terraces is insignificant, and the presence of vegetation can effectively reduce the bed shear stress.

  4. Development of an automated multi-stage modal synthesis system for NASTRAN

    Science.gov (United States)

    Herting, D. N.; Hoesly, R. L.

    1977-01-01

    A mode synthesis development to be scheduled in the NASTRAN multi-level substructuring system for general dynamics applications is described. The method combines the better features of several state of the art mode synthesis techniques, yet is general enough to provide for any arbitrary combination of boundary degrees of freedom and normal mode boundary conditions. Normal modes or complex eigenvectors may be used in the definition of a structure component which may be combined with other components of any type. Combination structures fabricated from component modes may be processed as normal substructures, including further multi-stage mode synthesis reductions. Included are discussions of the user control of the system and advantages in actual application.

  5. Simulation of Multi-component Multi-stage Separation Process--An Improved Algorithm and Application

    Institute of Scientific and Technical Information of China (English)

    李春山; 张香平; 张锁江; 谭心舜; 项曙光

    2006-01-01

    This paper presents a flexible model and a robust algorithm for simulation of multi-stage multi-component separation processes in which multiple feeds, side streams, strippers and/or side heat exchangers are involved. The improved algorithm effectively accelerates the speed of convergence and offers better stability by introducing a damping factor for updating the stripping factor, and also reduces the requirement on the initial estimates by updating the Joacobian matrix directly with the stripping factor and enthalpy. On the other hand, an efficient algorithm was proposed to solve the approximate tri-diagonal matrix (containing the off-band elements) derived from the material balance equations (Mequations)and phase equilibrium equations (E equations), the advantages and simplicity of the "inside-out" technique of the Russell are retained. The present algorithm was demonstrated to be effective in simulating complex separation columns with typical case studies.

  6. A multi-stage approach for damage detection in structural systems based on flexibility

    Science.gov (United States)

    Grande, E.; Imbimbo, M.

    2016-08-01

    The paper proposes a fusion approach for damage detection in structural applications in the case of multiple damage locations and three-dimensional systems. Based on the Dempster-Shafer evidence theory, a multi-stage approach is proposed with the mode shapes assumed as primary sources and local decisions based on a flexibility method. The proposed approach has been applied to two case studies, a a fixed end beam analyzed in other papers and a three dimensional structures codified in a Benchmark problem. Both the case studies have shown the ability and the efficiency of the proposed approach to detect damage also in the case of multiple damage, limited number of identified parameters and noise measurements.

  7. Optimization of Adaboost Algorithm for Sonar Target Detection in a Multi-Stage ATR System

    Science.gov (United States)

    Lin, Tsung Han (Hank)

    2011-01-01

    JPL has developed a multi-stage Automated Target Recognition (ATR) system to locate objects in images. First, input images are preprocessed and sent to a Grayscale Optical Correlator (GOC) filter to identify possible regions-of-interest (ROIs). Second, feature extraction operations are performed using Texton filters and Principal Component Analysis (PCA). Finally, the features are fed to a classifier, to identify ROIs that contain the targets. Previous work used the Feed-forward Back-propagation Neural Network for classification. In this project we investigate a version of Adaboost as a classifier for comparison. The version we used is known as GentleBoost. We used the boosted decision tree as the weak classifier. We have tested our ATR system against real-world sonar images using the Adaboost approach. Results indicate an improvement in performance over a single Neural Network design.

  8. An integrated multi-stage supply chain inventory model with imperfect production process

    Directory of Open Access Journals (Sweden)

    Soumita Kundu

    2015-09-01

    Full Text Available This paper deals with an integrated multi-stage supply chain inventory model with the objective of cost minimization by synchronizing the replenishment decisions for procurement, production and delivery activities. The supply chain structure examined here consists of a single manufacturer with multi-buyer where manufacturer orders a fixed quantity of raw material from outside suppliers, processes the materials and delivers the finished products in unequal shipments to each customer. In this paper, we consider an imperfect production system, which produces defective items randomly and assumes that all defective items could be reworked. A simple algorithm is developed to obtain an optimal production policy, which minimizes the expected average total cost of the integrated production-inventory system.

  9. A multi-stage random forest classifier for phase contrast cell segmentation.

    Science.gov (United States)

    Essa, Ehab; Xie, Xianghua; Errington, Rachel J; White, Nick

    2015-01-01

    We present a machine learning based approach to automatically detect and segment cells in phase contrast images. The proposed method consists of a multi-stage classification scheme based on random forest (RF) classifier. Both low level and mid level image features are used to determine meaningful cell regions. Pixel-wise RF classification is first carried out to categorize pixels into 4 classes (dark cell, bright cell, halo artifact, and background) and generate a probability map for cell regions. K-means clustering is then applied on the probability map to group similar pixels into candidate cell regions. Finally, cell validation is performed by another RF to verify the candidate cell regions. The proposed method has been tested on U2-OS human osteosarcoma phase contrast images. The experimental results show better performance of the proposed method with precision 92.96% and recall 96.63% compared to a state-of-the-art segmentation technique. PMID:26737137

  10. Generation of High Pressure Oxygen via Electrochemical Pumping in a Multi-stage Electrolysis Stack

    Science.gov (United States)

    Setlock, John A (Inventor); Green, Robert D (Inventor); Farmer, Serene (Inventor)

    2016-01-01

    An oxygen pump can produce high-purity high-pressure oxygen. Oxygen ions (O.sup.2-) are electrochemically pumped through a multi-stage electrolysis stack of cells. Each cell includes an oxygen-ion conducting solid-state electrolyte between cathode and anode sides. Oxygen dissociates into the ions at the cathode side. The ions migrate across the electrolyte and recombine at the anode side. An insulator is between adjacent cells to electrically isolate each individual cell. Each cell receives a similar volt potential. Recombined oxygen from a previous stage can diffuse through the insulator to reach the cathode side of the next stage. Each successive stage similarly incrementally pressurizes the oxygen to produce a final elevated pressure.

  11. Solar Multi-stage Refrigeration Systems on the Basis of Absorber with the Internal Evaporative Cooling

    Directory of Open Access Journals (Sweden)

    Doroshenko A.V.

    2015-08-01

    Full Text Available In the article, the developed schematics are presented for the alternative refrigeration systems and air-conditioning systems, based on the use of absorbing cycle and solar energy for the regeneration of absorbent solution. Multi-stage principle of construction of drying and cool contours of solar systems is used with growth of concentration of absorbent on the stages of cooler. An absorber with internal evaporative cooling, allowing to remove the separate evaporated cooler, usually included after the absorber of the proper stage, is developed. Heat-mass-transfer apparatus of film-type, entering in the complement of drying and cool contours compatible and executed on the basis of multichannel compositions from polymeric materials. The preliminary comparative analysis of possibilities of the solar refrigeration systems and air-conditioning systems is executed.

  12. Multi-Stage Optimization Based Automatic Voltage Control Systems Considering Wind Power Forecasting Errors

    DEFF Research Database (Denmark)

    Qin, Nan; Bak, Claus Leth; Abildgaard, Hans;

    2016-01-01

    This paper proposes an automatic voltage control (AVC) system for power systems with limited continuous voltage control capability. The objective is to minimize the operational cost over a period, which consists of the power loss in the grid, the shunt switching cost, the transformer tap change...... cost and the generator reactive power output cost. The problem is formulated in a multi-stage optimal reactive power flow (MORPF) framework, solved by the nonlinear programming techniques via a rolling process. The voltage uncertainty caused by wind power forecasting errors is considered in the optimal...... electricity control center, where study cases based on the western Danish power system demonstrate the superiority of the proposed AVC system in term of the cost minimization. Monte Carlo simulations are carried out to verify the proposed method on the robustness improvements....

  13. Multi-stage full waveform inversion strategy for 2D elastic VTI media

    KAUST Repository

    Oh, Ju-Won

    2015-08-19

    One of the most important issues in the multi-parametric full waveform inversion (FWI) is to find an optimal parameterization, which helps us recover the subsurface anisotropic parameters as well as seismic velocities, with minimal tradeoff. As a result, we analyze three different parameterizations for elastic VTI media in terms of the influence of the S-waves on the gradient direction for c13, the spatial coverage of gradient direction and the degree of trade-offs between the parameters. Based on the dependency results, we design a multi-stage elastic VTI FWI strategy to enhance both the spatial coverage of the FWI and the robustness to the trade-offs among the parameters as well as FWI for the c13 structure.

  14. Modeling Humans as Reinforcement Learners: How to Predict Human Behavior in Multi-Stage Games

    Science.gov (United States)

    Lee, Ritchie; Wolpert, David H.; Backhaus, Scott; Bent, Russell; Bono, James; Tracey, Brendan

    2011-01-01

    This paper introduces a novel framework for modeling interacting humans in a multi-stage game environment by combining concepts from game theory and reinforcement learning. The proposed model has the following desirable characteristics: (1) Bounded rational players, (2) strategic (i.e., players account for one anothers reward functions), and (3) is computationally feasible even on moderately large real-world systems. To do this we extend level-K reasoning to policy space to, for the first time, be able to handle multiple time steps. This allows us to decompose the problem into a series of smaller ones where we can apply standard reinforcement learning algorithms. We investigate these ideas in a cyber-battle scenario over a smart power grid and discuss the relationship between the behavior predicted by our model and what one might expect of real human defenders and attackers.

  15. 煤液化重质产物的催化加氢裂解研究%Study of catalytic hydrocracking of asphaltenes from heavy products of coal liquefaction

    Institute of Scientific and Technical Information of China (English)

    康士刚; 宗志敏; 水恒福; 王知彩; 魏贤勇

    2011-01-01

    为了使煤直接液化的重质产物转化为轻质油类,利用管式高压反应釜,以四氢萘为溶剂、FeS和S为催化剂,对沥青烯进行了加氢裂解研究.考察了催化剂种类及加入量、反应温度和反应压力等因素对沥青烯加氢液化的转化率和产物分布的影响.利用FTIR与元素分析仪对原料沥青烯及残余沥青烯进行了结构表征.结果表明:在一定实验条件下,FeS加硫后使原料的转化率由30.76%增加至53.94%,油+气的产率也由6.01%增至38.39%,而逆向缩合程度减少了9%;两种催化体系下原料的液化转化率均随着温度的升高而增加,但不加硫时增加的幅度为15.20%,明显小于加硫时的23.83%;随着压力的增加,两种催化条件下原料的转化率均增加,而逆向缩合程度在不加硫时随着压力的增加而增加(16.17%,6~30.54%),加硫时则相反.%In order to upgrading the heavy products from Xiaolongtan lignite liquefaction, the hydrocracking experiments of asphaltenes (AS) were carried out with tetralin as solvent and FeS or sulfur as catalyst in a batch micro-autoclave. The effects of types and amount of catalyst, reaction temperature and hydrogen pressure on the distribution of liquefied products were investigated. The elementary and FTIR analyses were used to illustrate the structural characteristics of feedstock AS and residue ASs. The results indicate that under specific conditions,the addition of sulfur into FeS catalyst increases the conversion of feedstock AS from 30. 76 %to 53.94% with the yield of oil+gas from 6.01% to 38.39%. The retrogressive condensation is reduced by 9%. In the two cases, both the conversions of feedstock AS increase with the increasing of reaction temperature. The conversion increment of 15.20% without sulfur addition is distinctly lower than that of 23.83% with sulfur addition. With the increasing of initial H2 pressure, the conversions of feedstock AS increase in the two cases, where

  16. Nonlinear resonances in a multi-stage free-electron laser amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, S. [Graduate Univ. for Advanced Studies, Ibaraki-ken (Japan); Takayama, K. [National Lab. for High Energy Physics, Ibaraki-ken (Japan)

    1995-12-31

    A two-beam accelerator (TBA) is a possible candidate of future linear colliders, in which the demanded rf power is provided by a multi-stage free-electron laser (MFEL). After if amplification in each stage, a driving beam is re-accelerated by an induction unit and propagates into the next stage. Recently it has been recognized that the multi-stage character of the MFEL causes resonances between its periodicity and the synchrotron motion in an rf bucket. Since the synchrotron oscillation is strongly modulated by the resonance and at the worst a large fraction of particles is trapped in the resonance islands, the nonlinear resonances in the FEL longitudinal beam dynamics can lead to notable degradation of the MFEL performance, such as output fluctuation and phase modulation which have been big concerns in the accelerator society. The overall efficiency of the MFEL and the quality of the amplified microwave power are key issues for realizing the TBA/FEL Particularly the rf phase and amplitude errors must be maintained within tolerance. One of significant obstacles is an amplification of undesired modes. If a small-size waveguide is employed, the FEL resonance energies for undesired higher order modes shift very far from that for a fundamental mode; so it is possible to prevent higher order modes from evolving. Such a small-size waveguide, however, gives a high power density in the FEL. Simulation results have demonstrated that the nonlinear resonances occur in die FEL longitudinal motion when the power density exceeds some threshold. An analytical method for studying the nonlinear resonance in the TBA/FEL is developed based on the macroparticle model which can describe analytically the drastic behaviors in the evolutions of the phase and amplitude. In the theory the basic 1D-FEL equations are reduced to a nonlinear pendulum equation with respect to the ponderomotive phase.

  17. Lumped-equivalent circuit model for multi-stage cascaded magnetoelectric dual-tunable bandpass filter

    Institute of Scientific and Technical Information of China (English)

    张秋实; 朱锋杰; 周浩淼

    2015-01-01

    A lumped-equivalent circuit model of a novel magnetoelectric tunable bandpass filter, which is realized in the form of multi-stage cascading between a plurality of magnetoelectric laminates, is established in this paper for convenient analysis. The multi-stage cascaded filter is degraded to the coupling microstrip filter with only one magnetoelectric laminate and then compared with the existing experiment results. The comparison reveals that the insertion loss curves predicted by the degraded circuit model are in good agreement with the experiment results and the predicted results of the electromagnetic field simulation, thus the validity of the model is verified. The model is then degraded to the two-stage cascaded magneto-electric filter with two magnetoelectric laminates. It is revealed that if the applied external bias magnetic or electric fields on the two magnetoelectric laminates are identical, then the passband of the filter will drift under the changed external field; that is to say, the filter has the characteristics of external magnetic field tunability and electric field tunability. If the applied external bias magnetic or electric fields on two magnetoelectric laminates are different, then the passband will disappear so that the switching characteristic is achieved. When the same magnetic fields are applied to the laminates, the passband bandwidth of the two-stage cascaded magnetoelectric filter with two magnetoelectric laminates becomes nearly doubled in comparison with the passband filter which contains only one magnetoelectric laminate. The bandpass effect is also improved obviously. This research will provide a theoretical basis for the design, preparation, and application of a new high performance magnetoelectric tunable microwave device.

  18. Evaluation of wastewater treatment requirements for thermochemical biomass liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, D C [Pacific Northwest Lab., Richland, WA (United States)

    1992-04-01

    Biomass can provide a substantial energy source. Liquids are preferred for use as transportation fuels because of their high energy density and handling ease and safety. Liquid fuel production from biomass can be accomplished by any of several different processes including hydrolysis and fermentation of the carbohydrates to alcohol fuels, thermal gasification and synthesis of alcohol or hydrocarbon fuels, direct extraction of biologically produced hydrocarbons such as seed oils or algae lipids, or direct thermochemical conversion of the biomass to liquids and catalytic upgrading to hydrocarbon fuels. This report discusses direct thermochemical conversion to achieve biomass liquefaction and the requirements for wastewater treatment inherent in such processing. 21 refs.

  19. Marine impact on liquefaction processes

    NARCIS (Netherlands)

    Osch, M.M.E. van; Belfroid, S.P.C.; Oldenburg, M.

    2010-01-01

    In the last decade the interest for liquefied natural gas (LNG) is growing. A tendency is to produce and transport LNG on large floating vessels. One important choice in designing such a vessel is the liquefaction process. Several processes have been developed in recent years, ranging from mixed ref

  20. The multi-stage fitness test as a predictor of endurance fitness in wheelchair athletes.

    Science.gov (United States)

    Goosey-Tolfrey, Victoria L; Tolfrey, Keith

    2008-03-01

    The aims of this study were two-fold: (1) to consider the criterion-related validity of the multi-stage fitness test (MSFT) by comparing the predicted maximal oxygen uptake (.VO(2max)) and distance travelled with peak oxygen uptake (VO(2peak)) measured using a wheelchair ergometer (n = 24); and (2) to assess the reliability of the MSFT in a sub-sample of wheelchair athletes (n = 10) measured on two occasions. Twenty-four trained male wheelchair basketball players (mean age 29 years, s = 6) took part in the study. All participants performed a continuous incremental wheelchair ergometer test to volitional exhaustion to determine .VO(2peak), and the MSFT on an indoor wooden basketball court. Mean ergometer .VO(2peak) was 2.66 litres . min(-1) (s = 0.49) and peak heart rate was 188 beats . min(-1) (s = 10). The group mean MSFT distance travelled was 2056 m (s = 272) and mean peak heart rate was 186 beats . min(-1) (s = 11). Low to moderate correlations (rho = 0.39 to 0.58; 95% confidence interval [CI]: -0.02 to 0.69 and 0.23 to 0.80) were found between distance travelled in the MSFT and different expressions of wheelchair ergometer .VO(2peak). There was a mean bias of -1.9 beats . min(-1) (95% CI: -5.9 to 2.0) and standard error of measurement of 6.6 beats . min(-1) (95% CI: 5.4 to 8.8) between the ergometer and MSFT peak heart rates. A similar comparison of ergometer and predicted MSFT .VO(2peak) values revealed a large mean systematic bias of 15.3 ml . kg(-1) . min(-1) (95% CI: 13.2 to 17.4) and standard error of measurement of 3.5 ml . kg(-1) . min(-1) (95% CI: 2.8 to 4.6). Small standard errors of measurement for MSFT distance travelled (86 m; 95% CI: 59 to 157) and MSFT peak heart rate (2.4 beats . min(-1); 95% CI: 1.7 to 4.5) suggest that these variables can be measured reliably. The results suggest that the multi-stage fitness test provides reliable data with this population, but does not fully reflect the aerobic capacity of wheelchair athletes directly. PMID

  1. Research and Development for Multi-stage and Integrated Approach for Seafloor Massive Sulfides (SMSs) Exploration.

    Science.gov (United States)

    Asakawa, Eiichi; Sumi, Tomonori; Kadoshima, Kazuyuki; Kose, Masami; Lee, Sangkyun; Murakami, Fumitoshi; Tsukahara, Hitoshi; Koizumi, Akira; Koizumi, Yukiko; Ikeda, Makoto; Higashi, Michio

    2016-04-01

    The Cabinet Office, Government Japan started the Cross-ministerial Strategic Innovation Promotion Program (SIP) in 2014. "Next-generation Ocean Resource Exploration Techniques" is scheduled under SIP from 2014 to 2018. J-MARES (Research and Development Partnership for Next Generation Technology of Marine Resources Survey) participates this program and aims "Multi-stage and integrated approach for SMSs exploration" through the development of highly efficient and cost-effective geophysical exploration methods mainly on seismic and electric-magnetic methods, and combination of the known exploration tools and systems. J-MARES proposed Vertical Cable Seismic (VCS) technique as seismic survey. It is one of reflection seismic methods that uses hydrophone arrays vertically moored from the seafloor. It is useful to delineate detailed structures in a spatially-limited area efficiently. JGI, a member of J-MARES, has developed autonomous VCS systems and carried out several VCS surveys in hydrothermal fields in Okinawa Trough. By the VCS survey, the detailed subsurface structure is revealed and velocity is estimated up to 100m. Then we could recognize the buried sulfide deposit beneath the sediments. As for EM survey, the system has been originally developed by Waseda University. The system is towed closely to seafloor using ROV. It is one of Time Domain EM (TDEM) survey systems that consists of a loop coil and a 3 component high-sensitive magnetometer. By analyzing the decay curve of the transient magnetic field induced by the loop coil, the subsurface resistivity structure is estimated. The exploration depth depends on the measurement time and it is designed up to 100m enough for SMS exploration. We carried out the EM surveys around the north mound along VCS survey lines in Izena Hole, Okinawa-trough. The EM survey detects the highly conductive zone around the north mound. The efficiency is 3 times faster than the conventional TDEM measurement on the ocean bottom. Based on

  2. Research and Development for Multi-stage and Integrated Approach for Seafloor Massive Sulfides (SMSs) Exploration.

    Science.gov (United States)

    Lee, S.; Asakawa, E.; Sumi, T.; Kadoshima, K.; Kose, M.; Murakami, F.; Tsukahara, H.; Koizumi, A.; Koizumi, Y.; Ikeda, M.; Higashi, M.

    2015-12-01

    The seafloor hydrothermal systems and related mineral deposits had been discovered at more than 550 sites so for, and near the one-third of these sites were confirmed as the massive sulfide deposits (Hannington et al., 2011). However, we are now faced with the some task like the preservation of hydrothermal vent community and the secure of amount of mineral reserves for the commercialization. In Japan, the exploration and investigation researches in Japan's EEZ has been conducted from 1980s, and about 20 seafloor hydrothermal fields including several confirmed SMSs has been discovered so far. The Cabinet Office of Government Japan (2013) have been promoting "assessment of the amount of reserves of known mineral deposits, discovery of new mineral deposits and comprehension of the approximate amount of reserves, development of equipment technologies and environmental impact assessment methods related to mining and lifting, including actual offshore tests", expecting projects to be initiated aiming at commercialization with the participation of private companies in or after FY2023-FY2027. As part of the promotion, the "Cross-ministerial Strategic Innovation Promotion Program (SIP)" was started at FY2014 by the Cabinet Office of Government Japan, and the research project of "Next-generation technology for ocean resources exploration" is also ongoing (FY2014-FY2018). J-MARES(Research and Development Partnership for Next Generation Technology of Marine Resources Survey) is one of the private union participated the SIP organized four Inc.(JAPAX, JGI, NSENGI, and MMTEC) aimed at construction of "Multi-stage and integrated approach for SMSs exploration" through the development of upgradable and effectual geophysical exploration methods on seismic and electric-magnetic methods, and combination of the known exploration tools and systems. In this presentation, we introduce some results obtained from two research cruise (JM14-01 and JM14-02) on the known seafloor hydrothermal

  3. Coal liquefaction. Quarterly report, April--June 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    The United States has more energy available in coal than in petroleum, natural gas, oil shale, and tar sands combined. Nationwide energy shortages, together with the availability of abundant coal reserves, make commercial production of synthetic fuels from coal vital to the Nation's total supply of clean energy. In response to this need, the Office of Fossil Energy of the Energy Research and Development Administration (ERDA) is conducting a research and development program to provide technology that will permit rapid commercialization of processes for converting coal to synthetic liquid and gaseous fuels and for improved direct combustion of coal. These fuels must be storable and suitable for power generation, transportation, and residential and industrial uses. ERDA's program for the conversion of coal to liquid fuels was begun by two of ERDA's predecessor agencies: Office of Coal Research (OCR) in 1962, and Bureau of Mines, U.S. Department of the Interior, in the 1930's. Current work in coal liquefaction is aimed at improved process configurations for both catalytic and non-catalytic processes to provide more attractive processing economics and lower capital investment. Coal liquefaction can now be achieved under more moderate processing conditions and more rapidly than was the case in the 1930's. The advantage of coal liquefaction is that the entire range of liquid products, including heavy boiler fuel, distillate fuel oil, gasoline, jet fuel, and diesel oil, can be produced from coal by varying the type of process and operating conditions used in the process. Furthermore, coal-derived liquid fuels also have the potential for use as chemical feedstocks. To determine the most efficient means of utilizing coal resources, ERDA is sponsoring the development of several conversion processes that are currently in the pilot plant stage. Nineteen projects under development are described and progress for each in the quarter is detailed briefly

  4. Multi-Stage Feature Selection Based Intelligent Classifier for Classification of Incipient Stage Fire in Building

    Directory of Open Access Journals (Sweden)

    Allan Melvin Andrew

    2016-01-01

    Full Text Available In this study, an early fire detection algorithm has been proposed based on low cost array sensing system, utilising off- the shelf gas sensors, dust particles and ambient sensors such as temperature and humidity sensor. The odour or “smellprint” emanated from various fire sources and building construction materials at early stage are measured. For this purpose, odour profile data from five common fire sources and three common building construction materials were used to develop the classification model. Normalised feature extractions of the smell print data were performed before subjected to prediction classifier. These features represent the odour signals in the time domain. The obtained features undergo the proposed multi-stage feature selection technique and lastly, further reduced by Principal Component Analysis (PCA, a dimension reduction technique. The hybrid PCA-PNN based approach has been applied on different datasets from in-house developed system and the portable electronic nose unit. Experimental classification results show that the dimension reduction process performed by PCA has improved the classification accuracy and provided high reliability, regardless of ambient temperature and humidity variation, baseline sensor drift, the different gas concentration level and exposure towards different heating temperature range.

  5. A Multi-Stage Reverse Logistics Network Problem by Using Hybrid Priority-Based Genetic Algorithm

    Science.gov (United States)

    Lee, Jeong-Eun; Gen, Mitsuo; Rhee, Kyong-Gu

    Today remanufacturing problem is one of the most important problems regarding to the environmental aspects of the recovery of used products and materials. Therefore, the reverse logistics is gaining become power and great potential for winning consumers in a more competitive context in the future. This paper considers the multi-stage reverse Logistics Network Problem (m-rLNP) while minimizing the total cost, which involves reverse logistics shipping cost and fixed cost of opening the disassembly centers and processing centers. In this study, we first formulate the m-rLNP model as a three-stage logistics network model. Following for solving this problem, we propose a Genetic Algorithm pri (GA) with priority-based encoding method consisting of two stages, and introduce a new crossover operator called Weight Mapping Crossover (WMX). Additionally also a heuristic approach is applied in the 3rd stage to ship of materials from processing center to manufacturer. Finally numerical experiments with various scales of the m-rLNP models demonstrate the effectiveness and efficiency of our approach by comparing with the recent researches.

  6. Hydraulic design to optimize the treatment capacity of Multi-Stage Filtration units

    Science.gov (United States)

    Mushila, C. N.; Ochieng, G. M.; Otieno, F. A. O.; Shitote, S. M.; Sitters, C. W.

    2016-04-01

    Multi-Stage Filtration (MSF) can provide a robust treatment alternative for surface water sources of variable water quality in rural communities at low operation and maintenance costs. MSF is a combination of Slow Sand Filters (SSFs) and Pre-treatment systems. The general objective of this research was to optimize the treatment capacity of MSF. A pilot plant study was undertaken to meet this objective. The pilot plant was monitored for a continuous 98 days from commissioning till the end of the project. Three main stages of MSF namely: The Dynamic Gravel Filter (DGF), Horizontal-flow Roughing Filter (HRF) and SSF were identified, designed and built. The response of the respective MSF units in removal of selected parameters guiding drinking water quality such as microbiological (Faecal and Total coliform), Suspended Solids, Turbidity, PH, Temperature, Iron and Manganese was investigated. The benchmark was the Kenya Bureau (KEBS) and World Health Organization (WHO) Standards for drinking water quality. With respect to microbiological raw water quality improvement, MSF units achieved on average 98% Faecal and 96% Total coliform removal. Results obtained indicate that implementation of MSF in rural communities has the potential to increase access to portable water to the rural populace with a probable consequent decrease in waterborne diseases. With a reduced down time due to illness, more time would be spent in undertaking other economic activities.

  7. A multi-stage genome-wide association study of bladder cancer identifies multiple susceptibility loci

    Science.gov (United States)

    Rothman, Nathaniel; Garcia-Closas, Montserrat; Chatterjee, Nilanjan; Malats, Nuria; Wu, Xifeng; Figueroa, Jonine; Real, Francisco X; Van Den Berg, David; Matullo, Giuseppe; Baris, Dalsu; Thun, Michael; Kiemeney, Lambertus A; Vineis, Paolo; De Vivo, Immaculata; Albanes, Demetrius; Purdue, Mark P; Rafnar, Thorunn; Hildebrandt, Michelle A T; Kiltie, Anne E; Cussenot, Olivier; Golka, Klaus; Kumar, Rajiv; Taylor, Jack A; Mayordomo, Jose I; Jacobs, Kevin B; Kogevinas, Manolis; Hutchinson, Amy; Wang, Zhaoming; Fu, Yi-Ping; Prokunina-Olsson, Ludmila; Burdette, Laurie; Yeager, Meredith; Wheeler, William; Tardón, Adonina; Serra, Consol; Carrato, Alfredo; García-Closas, Reina; Lloreta, Josep; Johnson, Alison; Schwenn, Molly; Karagas, Margaret R; Schned, Alan; Andriole, Gerald; Grubb, Robert; Black, Amanda; Jacobs, Eric J; Diver, W Ryan; Gapstur, Susan M; Weinstein, Stephanie J; Virtamo, Jarmo; Cortessis, Victoria K; Gago-Dominguez, Manuela; Pike, Malcolm C; Stern, Mariana C; Yuan, Jian-Min; Hunter, David; McGrath, Monica; Dinney, Colin P; Czerniak, Bogdan; Chen, Meng; Yang, Hushan; Vermeulen, Sita H; Aben, Katja K; Witjes, J Alfred; Makkinje, Remco R; Sulem, Patrick; Besenbacher, Soren; Stefansson, Kari; Riboli, Elio; Brennan, Paul; Panico, Salvatore; Navarro, Carmen; Allen, Naomi E; Bueno-de-Mesquita, H Bas; Trichopoulos, Dimitrios; Caporaso, Neil; Landi, Maria Teresa; Canzian, Federico; Ljungberg, Borje; Tjonneland, Anne; Clavel-Chapelon, Francoise; Bishop, David T; Teo, Mark T W; Knowles, Margaret A; Guarrera, Simonetta; Polidoro, Silvia; Ricceri, Fulvio; Sacerdote, Carlotta; Allione, Alessandra; Cancel-Tassin, Geraldine; Selinski, Silvia; Hengstler, Jan G; Dietrich, Holger; Fletcher, Tony; Rudnai, Peter; Gurzau, Eugen; Koppova, Kvetoslava; Bolick, Sophia C E; Godfrey, Ashley; Xu, Zongli; Sanz-Velez, José I; García-Prats, María D; Sanchez, Manuel; Valdivia, Gabriel; Porru, Stefano; Benhamou, Simone; Hoover, Robert N; Fraumeni, Joseph F; Silverman, Debra T; Chanock, Stephen J

    2010-01-01

    We conducted a multi-stage, genome-wide association study (GWAS) of bladder cancer with a primary scan of 589,299 single nucleotide polymorphisms (SNPs) in 3,532 cases and 5,120 controls of European descent (5 studies) followed by a replication strategy, which included 8,381 cases and 48,275 controls (16 studies). In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1; rs1014971, (P=8×10−12) maps to a non-genic region of chromosome 22q13.1; rs8102137 (P=2×10−11) on 19q12 maps to CCNE1; and rs11892031 (P=1×10−7) maps to the UGT1A cluster on 2q37.1. We confirmed four previous GWAS associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3, validated previous candidate associations for the GSTM1 deletion (P=4×10−11) and a tag SNP for NAT2 acetylation status (P=4×10−11), as well as demonstrated smoking interactions with both regions. Our findings on common variants associated with bladder cancer risk should provide new insights into mechanisms of carcinogenesis. PMID:20972438

  8. Variation transmission model for setting acceptance criteria in a multi-staged pharmaceutical manufacturing process.

    Science.gov (United States)

    Montes, Richard O

    2012-03-01

    Pharmaceutical manufacturing processes consist of a series of stages (e.g., reaction, workup, isolation) to generate the active pharmaceutical ingredient (API). Outputs at intermediate stages (in-process control) and API need to be controlled within acceptance criteria to assure final drug product quality. In this paper, two methods based on tolerance interval to derive such acceptance criteria will be evaluated. The first method is serial worst case (SWC), an industry risk minimization strategy, wherein input materials and process parameters of a stage are fixed at their worst-case settings to calculate the maximum level expected from the stage. This maximum output then becomes input to the next stage wherein process parameters are again fixed at worst-case setting. The procedure is serially repeated throughout the process until the final stage. The calculated limits using SWC can be artificially high and may not reflect the actual process performance. The second method is the variation transmission (VT) using autoregressive model, wherein variation transmitted up to a stage is estimated by accounting for the recursive structure of the errors at each stage. Computer simulations at varying extent of variation transmission and process stage variability are performed. For the scenarios tested, VT method is demonstrated to better maintain the simulated confidence level and more precisely estimate the true proportion parameter than SWC. Real data examples are also presented that corroborate the findings from the simulation. Overall, VT is recommended for setting acceptance criteria in a multi-staged pharmaceutical manufacturing process.

  9. Multi-Stage Metering Mechanism for Transplanting of Vegetable Seedlings in Paper Pots

    Science.gov (United States)

    Nandede, B. M.; Raheman, H.

    2015-12-01

    A multi-stage rotating cup type metering mechanism was developed for transplanting of vegetable seedlings of tomato, brinjal and chili raised in paper pots. The developed setup consisted of a seedling feeding wheel, metering wheel, fixed slotted plate, seedling delivery tube, furrow opener, furrow closer and a power transmission system. Its evaluation was carried out with pot seedlings of tomato, brinjal and chili of 8-11 cm height at five forward speeds (0.6, 0.9, 1.2, 2.2 and 3.2 km/h) and two plant spacings (45 and 60 cm) in controlled soil bin condition. The mean values of feeding efficiency, conveying efficiency, planting efficiency and overall efficiency of the multistage metering unit were observed to be higher than 90 % for forward speeds of 0.6 to 2.2 km/h. With further increase in speed to 3.2 km/h, the feeding and conveying efficiency were observed to be higher than 90 %, whereas, the planting efficiency drastically reduced to around 50 % due to the problem in getting the pot seedlings vertically in the furrow. Also the seedlings were falling into the furrow at an angle greater than 70° to the vertical, hence not suitable for transplanting.

  10. Lymphoma diagnosis in histopathology using a multi-stage visual learning approach

    Science.gov (United States)

    Codella, Noel; Moradi, Mehdi; Matasar, Matt; Sveda-Mahmood, Tanveer; Smith, John R.

    2016-03-01

    This work evaluates the performance of a multi-stage image enhancement, segmentation, and classification approach for lymphoma recognition in hematoxylin and eosin (H and E) stained histopathology slides of excised human lymph node tissue. In the first stage, the original histology slide undergoes various image enhancement and segmentation operations, creating an additional 5 images for every slide. These new images emphasize unique aspects of the original slide, including dominant staining, staining segmentations, non-cellular groupings, and cellular groupings. For the resulting 6 total images, a collection of visual features are extracted from 3 different spatial configurations. Visual features include the first fully connected layer (4096 dimensions) of the Caffe convolutional neural network trained from ImageNet data. In total, over 200 resultant visual descriptors are extracted for each slide. Non-linear SVMs are trained over each of the over 200 descriptors, which are then input to a forward stepwise ensemble selection that optimizes a late fusion sum of logistically normalized model outputs using local hill climbing. The approach is evaluated on a public NIH dataset containing 374 images representing 3 lymphoma conditions: chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), and mantle cell lymphoma (MCL). Results demonstrate a 38.4% reduction in residual error over the current state-of-art on this dataset.

  11. Optimal phasing of district heating network investments using multi-stage stochastic programming

    Directory of Open Access Journals (Sweden)

    Romain Stephane Claude Lambert

    2016-06-01

    Full Text Available Most design optimisation studies for district heating systems have focused on the optimal sizing of network assets and on the location of production units. However, the strategic value of the flexibility in phasing of the inherently modular heat networks, which is an important aspect in many feasibility studies for district heating schemes in the UK, is almost always neglected in the scientific literature. This paper considers the sequential problem faced by a decision-maker in the phasing of long-term investments into district heating networks and their expansions. The problem is formulated as a multi-stage stochastic programme to determine the annual capital expenditure that maximises the expected net present value of the project. The optimisation approach is illustrated by applying it to the hypothetical case of the UK’s Marston Vale eco town. It was found that the approach is capable of simulating the optimal growth of a network, from both a single heat source or separate islands of growth, as well as the optimal marginal expansion of an existing district heating network. The proposed approach can be used by decision makers as a framework to determine both the optimal phasing and extension of district heating networks and can be adapted simply to various, more complex real-life situations by introducing additional constraints and parameters. The versatility of the base formulation also makes it a powerful approach regardless of the size of the network and also potentially applicable to cooling networks.

  12. Remediation of soils contaminated with particulate depleted uranium by multi stage chemical extraction.

    Science.gov (United States)

    Crean, Daniel E; Livens, Francis R; Sajih, Mustafa; Stennett, Martin C; Grolimund, Daniel; Borca, Camelia N; Hyatt, Neil C

    2013-12-15

    Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction. Uranium rich particles with characteristic spherical morphologies were observed in soils, consistent with other instances of DU munitions contamination. Batch extraction efficiencies for aqueous ammonium bicarbonate (42-50% total DU extracted), citric acid (30-42% total DU) and sulphuric acid (13-19% total DU) were evaluated. Characterisation of residues from bicarbonate-treated soils by synchrotron microfocus X-ray diffraction and X-ray absorption spectroscopy revealed partially leached U(IV)-oxide particles and some secondary uranyl-carbonate phases. Based on these data, a multi-stage extraction scheme was developed utilising leaching in ammonium bicarbonate followed by citric acid to dissolve secondary carbonate species. Site specific U extraction was improved to 68-87% total U by the application of this methodology, potentially providing a route to efficient DU decontamination using low cost, environmentally compatible reagents. PMID:23998894

  13. Low-cost multi-stage filtration enhanced by coagulation-flocculation in upflow gravel filtration

    Directory of Open Access Journals (Sweden)

    L. D. Sánchez

    2012-06-01

    Full Text Available This paper assesses the operational and design aspects of coagulation and flocculation in upflow gravel filters (CF-UGF in a multi-stage filtration (MSF plant. This study shows that CF-UGF units improve the performance of MSF considerably, when the system operates with turbidity above 30 NTU. It strongly reduces the load of particulate material before the water enters in the slow sand filters (SSF and therewith avoids short filter runs and prevents early interruption in SSF operations. The removal efficiency of turbidity in the CF-UGF with coagulant was between 85 and 96%, whereas the average efficiency without coagulant dosing was 46% (range: 21–76%. Operating with coagulant also improves the removal efficiency for total coliforms, E-coli and HPC. No reduction was observed in the microbial activity of the SSF, no obstruction of the SSF bed was demonstrated and SSF runs were maintained between 50 and 70 days for a maximum head loss of 0.70 m. The most important advantage is the flexibility of the system to operate with and without coagulant according to the influent turbidity. It was only necessary for 20% of the time to operate with the coagulant. The CF-UGF unit represented 7% of total construction costs and the O&M cost for the use of coagulant represented only 0.3%.

  14. Multi-Bed Multi-Stage Adsorption Refrigeration Cycle-Reducing Driving Heat Source Temperature

    Science.gov (United States)

    Alam, K. C. Amanul; Akahira, Akira; Hamamoto, Yoshinori; Akisawa, Atsushi; Kashiwagi, Takao; Saha, Bidyut Baran; Koyama, Shigeru; Ng, Kim Choon; Chua, Hui Tong

    The study aims at designing a multi-bed multi-stage adsorption chiller that can be driven by waste heat at near ambient temperature. The chiller is designed such a way that it can be switched into different modes depending on the driving heat source temperature. Stage regeneration techniques have been applied to operate the chiller by relatively low temperature heat source. Driving heat source temperature is validated by simulated data and the performances obtained from different modes are compared. In terms of COP (Coefficient of performance),the chiller shows best performance in conventional single-stage mode for driving heat source temperature greater than 60°C, two stage mode for driving source temperature between 42 and 60°C,in three-stage mode for driving source temperature less than 42°C. In terms of cooling capacity, it shows the best performance in single-stage mode for heat source temperature greater than 70°C. The mass recovery process in single-stage mode is also examined. It is seen that the mass recovery process improve cooling capacity significantly, specially for the low regenerating temperature region.

  15. Rigging Test Bed Development for Validation of Multi-Stage Decelerator Extractions

    Science.gov (United States)

    Kenig, Sivan J.; Gallon, John C.; Adams, Douglas S.; Rivellini, Tommaso P.

    2013-01-01

    The Low Density Supersonic Decelerator project is developing new decelerator systems for Mars entry which would include testing with a Supersonic Flight Dynamics Test Vehicle. One of the decelerator systems being developed is a large supersonic ringsail parachute. Due to the configuration of the vehicle it is not possible to deploy the parachute with a mortar which would be the preferred method for a spacecraft in a supersonic flow. Alternatively, a multi-stage extraction process using a ballute as a pilot is being developed for the test vehicle. The Rigging Test Bed is a test venue being constructed to perform verification and validation of this extraction process. The test bed consists of a long pneumatic piston device capable of providing a constant force simulating the ballute drag force during the extraction events. The extraction tests will take place both inside a high-bay for frequent tests of individual extraction stages and outdoors using a mobile hydraulic crane for complete deployment tests from initial pack pull out to canopy extraction. These tests will measure line tensions and use photogrammetry to track motion of the elements involved. The resulting data will be used to verify packing and rigging as well, as validate models and identify potential failure modes in order to finalize the design of the extraction system.

  16. Low-cost multi-stage filtration enhanced by coagulation-flocculation in upflow gravel filtration

    Directory of Open Access Journals (Sweden)

    L. D. Sánchez

    2012-12-01

    Full Text Available This paper assesses the operational and design aspects of coagulation and flocculation in upflow gravel filters (CF-UGF in a multi-stage filtration (MSF plant. This study shows that CF-UGF units improve the performance of MSF considerably, when the system operates with turbidity above 30 NTU. It strongly reduces the load of particulate material before the water enters in the slow sand filters (SSF and therewith avoids short filter runs and prevents early interruption in SSF operations. The removal efficiency of turbidity in the CF-UGF with coagulant was between 85 and 96%, whereas the average efficiency without coagulant dosing was 46% (range: 21–76%. Operating with coagulant also improves the removal efficiency for total coliforms, E-coli and HPC. No reduction was observed in the microbial activity of the SSF, no obstruction of the SSF bed was demonstrated and SSF runs were maintained between 50 and 70 days for a maximum head loss of 0.70 m. The most important advantage is the flexibility of the system to operate with and without coagulant according to the influent turbidity. It was only necessary for 20% of the time to operate with the coagulant. The CF-UGF unit represented 7% of total construction costs and the O&M cost for the use of coagulant represented only 0.3%.

  17. Transport line for a multi-staged laser-plasma acceleration: DACTOMUS

    Energy Technology Data Exchange (ETDEWEB)

    Chancé, Antoine, E-mail: antoine.chance@cea.fr [CEA, IRFU, SACM, Centre de Saclay, F-91191 Gif-sur-Yvette (France); Delferrière, Olivier; Schwindling, Jérôme [CEA, IRFU, SACM, Centre de Saclay, F-91191 Gif-sur-Yvette (France); Bruni, Christelle; Delerue, Nicolas [LAL, UMR9607, CNRS and Université Paris Sud, Orsay (France); Specka, Arnd [LLR, UMR7638, CNRS and Ecole Polytechnique, Palaiseau (France); Cros, Brgitte; Maynard, Gillies; Paradkar, Bhooshan S. [LPGP, UMR8578, CNRS and Université Paris Sud, Orsay (France); Mora, Patrick [CPhT, UMR7644, CNRS and Ecole Polytechnique, Palaiseau (France)

    2014-03-11

    Laser-plasma acceleration is one of the most promising techniques to reach very high acceleration gradients up to a few hundreds of GeV/m. In order to push this acceleration scheme in the domain of the very high energies, the CILEX project was launched with the laser APOLLON. One of the main topics of this project is to study multi-staged acceleration. It consists in generating and pre-accelerating electrons in a first laser-plasma stage, to transport them up to a second stage where the electrons are accelerated again thanks to another laser pulse. The DACTOMUS project, based on a collaboration CEA-IRFU, CEA-IRAMIS, LAL, LPGP, LULI and LLR, aims at the study and realization of such a transfer line between these two stages. Firstly, a prototype will be developed and tested by the groups of CEA-IRAMIS-SPAM, LPGP, and LULI on the UHI100 facility (CEA-SPAM). This collaboration must enable to realize the first acceleration stage. For the transport line prototype, the main difficulties are to realize a very compact and energy accepting line with diagnostics to characterize the electron beam. We will present here the optics of this line, its performances and the inserted diagnostics.

  18. Transport line for a multi-staged laser-plasma acceleration: DACTOMUS

    Science.gov (United States)

    Chancé, Antoine; Delferrière, Olivier; Schwindling, Jérôme; Bruni, Christelle; Delerue, Nicolas; Specka, Arnd; Cros, Brgitte; Maynard, Gillies; Paradkar, Bhooshan S.; Mora, Patrick

    2014-03-01

    Laser-plasma acceleration is one of the most promising techniques to reach very high acceleration gradients up to a few hundreds of GeV/m. In order to push this acceleration scheme in the domain of the very high energies, the CILEX project was launched with the laser APOLLON. One of the main topics of this project is to study multi-staged acceleration. It consists in generating and pre-accelerating electrons in a first laser-plasma stage, to transport them up to a second stage where the electrons are accelerated again thanks to another laser pulse. The DACTOMUS project, based on a collaboration CEA-IRFU, CEA-IRAMIS, LAL, LPGP, LULI and LLR, aims at the study and realization of such a transfer line between these two stages. Firstly, a prototype will be developed and tested by the groups of CEA-IRAMIS-SPAM, LPGP, and LULI on the UHI100 facility (CEA-SPAM). This collaboration must enable to realize the first acceleration stage. For the transport line prototype, the main difficulties are to realize a very compact and energy accepting line with diagnostics to characterize the electron beam. We will present here the optics of this line, its performances and the inserted diagnostics.

  19. Short-Term Multi-Stage Stochastic Optimization of Hydropower Reservoirs Under Meteorological Uncertainty

    Science.gov (United States)

    Schwanenberg, D.; Naumann, S.; Allen, C.

    2014-12-01

    Hydroelectric power systems are characterized by variability and uncertainty in yield and water resources obligations. Market volatility and the growing number of operational constraints for flood control, navigation, environmental obligations and ancillary services (including load balancing requirements for renewable resources) further the need to quantify sources of uncertainty. This research presents an integrated framework to handle several sources of uncertainty. Main focus is on the meteorological forecast uncertainty based on deterministic and probabilistic Numerical Weather Predictions (NWP), its consistent propagation through load and streamflow forecasts, and the generation of scenario trees with novel multi-dimensional distance metrics. The scenario trees enable us to extend a deterministic optimization setup to a multi-stage stochastic optimization approach as the mathematical formulation of the short-term system management. The Federal Columbia River Power System (FCRPS), managed by the Bonneville Power Administration, the US Army Corps of Engineers and the Bureau of Reclamation, serves as a large-scale test case for the application of the new framework. We proof the feasibility of the new approach and verify the operational applicability within a real-time environment.

  20. INFLUENCE OF NANOFILTRATION PRETREATMENT ON SCALE DEPOSITION IN MULTI-STAGE FLASH THERMAL DESALINATION PLANTS

    Directory of Open Access Journals (Sweden)

    Aiman E Al-Rawajfeh

    2011-01-01

    Full Text Available Scale formation represents a major operational problem encountered in thermal desalination plants. In current installed plants, and to allow for a reasonable safety margin, sulfate scale deposition limits the top brine temperature (TBT in multi-stage flash (MSF distillers up to 110-112oC. This has significant effect on the unit capital, operational and water production cost. In this work, the influence of nanofiltration (NF pretreatment on the scale deposition potential and increasing TBT in MSF thermal desalination plants is modeled on the basis of mass transfer with chemical reaction of solutes in the brine. Full and partial NF-pretreatment of the feed water were investigated. TBT can be increased in MSF by increasing the percentage of NF-treated feed. Full NF pretreatment of the make-up allows TBT in the MSF plant to be raised up to 175oC in the case of di hybrid NF-MSF and up to 165oC in the case of tri hybrid NF-RO-MSF. The significant scale reduction is associated with increasing flashing range, unit recovery, unit performance, and will lead to reduction in heat transfer surface area, pumping power and therefore, water production cost.

  1. Indirect thermal liquefaction process for producing liquid fuels from biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kuester, J.L.

    1980-01-01

    A progress report on an indirect liquefaction process to convert biomass type materials to quality liquid hydrocarbon fuels by gasification followed by catalytic liquid fuels synthesis has been presented. A wide variety of feedstocks can be processed through the gasification system to a gas with a heating value of 500 + Btu/SCF. Some feedstocks are more attractive than others with regard to producing a high olefin content. This appears to be related to hydrocarbon content of the material. The H/sub 2//CO ratio can be manipulated over a wide range in the gasification system with steam addition. Some feedstocks require the aid of a water-gas shift catalyst while others appear to exhibit an auto-catalytic effect to achieve the conversion. H/sub 2/S content (beyond the gasification system wet scrubber) is negligible for the feedstocks surveyed. The water gas shift reaction appears to be enhanced with an increase in pyrolysis reactor temperature over the range of 1300 to 1700/sup 0/F. Reactor temperature in the Fischer-Tropsch step is a significant factor with regard to manipulating product composition analysis. The optimum temperature however will probably correspond to maximum conversion to liquid hydrocarbons in the C/sub 5/ - C/sub 17/ range. Continuing research includes integrated system performance assessment, alternative feedstock characterization (through gasification) and factor studies for gasification (e.g., catalyst usage, alternate heat transfer media, steam usage, recycle effects, residence time study) and liquefaction (e.g., improved catalysts, catalyst activity characterization).

  2. 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......-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....

  3. Quantitative Characterization of the Aqueous Fraction from Hydrothermal Liquefaction of Algae

    Energy Technology Data Exchange (ETDEWEB)

    Maddi, Balakrishna; Panisko, Ellen A.; Wietsma, Thomas W.; Lemmon, Teresa L.; Swita, Marie S.; Albrecht, Karl O.; Howe, Daniel T.

    2016-07-18

    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.

  4. Process Design and Economics for the Conversion of Algal Biomass to Hydrocarbons: Whole Algae Hydrothermal Liquefaction and Upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Susanne B.; Zhu, Yunhua; Anderson, Daniel B.; Hallen, Richard T.; Elliott, Douglas C.; Schmidt, Andrew J.; Albrecht, Karl O.; Hart, Todd R.; Butcher, Mark G.; Drennan, Corinne; Snowden-Swan, Lesley J.; Davis, Ryan; Kinchin, Christopher

    2014-03-20

    This report provides a preliminary analysis of the costs associated with converting whole wet algal biomass into primarily diesel fuel. Hydrothermal liquefaction converts the whole algae into an oil that is then hydrotreated and distilled. The secondary aqueous product containing significant organic material is converted to a medium btu gas via catalytic hydrothermal gasification.

  5. Earthquake Risk - MO 2013 Liquefaction Potential (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Soil liquefaction potential was determined using existing geologic and alluvium maps. Quaternary, Tertiary, and Cretaceous-age sediments, and alluvium deposits are...

  6. Remediation of soils contaminated with particulate depleted uranium by multi stage chemical extraction

    International Nuclear Information System (INIS)

    Highlights: • Batch leaching was examined to remediate soils contaminated with munitions depleted uranium. • Site specific maximum extraction was 42–50% total U in single batch with NH4HCO3. • Analysis of residues revealed partial leaching and secondary carbonate phases. • Sequential batch leaching alternating between NH4HCO3 and citric acid was designed. • Site specific extraction was increased to 68–87% total U in three batch steps. -- Abstract: Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction. Uranium rich particles with characteristic spherical morphologies were observed in soils, consistent with other instances of DU munitions contamination. Batch extraction efficiencies for aqueous ammonium bicarbonate (42–50% total DU extracted), citric acid (30–42% total DU) and sulphuric acid (13–19% total DU) were evaluated. Characterisation of residues from bicarbonate-treated soils by synchrotron microfocus X-ray diffraction and X-ray absorption spectroscopy revealed partially leached U(IV)-oxide particles and some secondary uranyl-carbonate phases. Based on these data, a multi-stage extraction scheme was developed utilising leaching in ammonium bicarbonate followed by citric acid to dissolve secondary carbonate species. Site specific U extraction was improved to 68–87% total U by the application of this methodology, potentially providing a route to efficient DU decontamination using low cost, environmentally compatible reagents

  7. Seepage flow behaviors of multi-stage fractured horizontal wells in arbitrary shaped shale gas reservoirs

    Science.gov (United States)

    Zhao, Yu-Long; Shan, Bao-Chao; Zhang, Lie-Hui; Liu, Qi-Guo

    2016-10-01

    The horizontal well incorporated with massive hydraulic fracturing has become a key and necessary technology to develop shale gas reservoirs efficiently, and transient pressure analysis is a practical method to evaluate the effectiveness of the fracturing. Until now, however, the related studies on the pressure of such wells have mainly focused on regular outer-boundaries, such as infinite, circular and rectangular boundary shapes, which do not always fulfill the practical conditions and, of course, could cause errors. By extending the boundary element method (BEM) into the application of multi-staged fractured horizontal wells, this paper presents a way of analyzing the transient pressure in arbitrary shaped shale gas reservoirs considering ad-/de-sorption and diffusion of the shale gas with the ‘tri-porosity’ mechanism model. The boundary integral equation can be obtained by coupling the fundamental solution of the Helmholtz equation with the dimensionless diffusivity equation. After discretizing the outer-boundaries and the fractures, the boundary integral equations are linearized and the coefficient matrix of the pressure on the boundaries is assembled, after which bottom-hole pressure can be calculated conveniently. Comparing the BEM solution with semi-analytical solution cases, the accuracy of the new solution can be validated. Then, the characteristic curves of the dimensionless pseudo pressure, as well as its derivative for a well in shale gas reservoirs, are drawn, based on which the parameters’ sensitivity analyses are also conducted. This paper not only enriches the well testing theory and method in shale gas reservoirs, but also provides an effective method to solve problems with complex inner- and outer-boundaries.

  8. A Palaeoproterozoic multi-stage hydrothermal alteration system at Nalunaq gold deposit, South Greenland

    Science.gov (United States)

    Bell, Robin-Marie; Kolb, Jochen; Waight, Tod Earle; Bagas, Leon; Thomsen, Tonny B.

    2016-07-01

    Nalunaq is an orogenic, high gold grade deposit situated on the Nanortalik Peninsula, South Greenland. Mineralisation is hosted in shear zone-controlled quartz veins, located in fine- and medium-grained amphibolite. The deposit was the site of Greenland's only operating metalliferous mine until its closure in 2014, having produced 10.67 t of gold. This study uses a combination of field investigation, petrography and U/Pb zircon and titanite geochronology to define a multi-stage hydrothermal alteration system at Nalunaq. A clinopyroxene-plagioclase-garnet(-sulphide) alteration zone (CPGZ) developed in the Nanortalik Peninsula, close to regional peak metamorphism and prior to gold-quartz vein formation. The ca. 1783-1762-Ma gold-quartz veins are hosted in reactivated shear zones with a hydrothermal alteration halo of biotite-arsenopyrite-sericite-actinolite-pyrrhotite(-chlorite-plagioclase-löllingite-tourmaline-titanite), which is best developed in areas of exceptionally high gold grades. Aplite dykes dated to ca. 1762 Ma cross-cut the gold-quartz veins, providing a minimum age for mineralisation. A hydrothermal calcite-titanite alteration assemblage is dated to ca. 1766 Ma; however, this alteration is highly isolated, and as a result, its field relationships are poorly constrained. The hydrothermal alteration and mineralisation is cut by several generations of ca. 1745-Ma biotite granodiorite accompanied by brittle deformation. A ca. 1745-Ma lower greenschist facies hydrothermal epidote-calcite-zoisite alteration assemblage with numerous accessory minerals forms halos surrounding the late-stage fractures. The contrasting hydrothermal alteration styles at Nalunaq indicate a complex history of exhumation from amphibolite facies conditions to lower greenschist facies conditions in an orogenic belt which resembles modern Phanerozoic orogens.

  9. Characterization of the impregnated iron based catalyst for direct coal liquefaction by EXAFS

    Institute of Scientific and Technical Information of China (English)

    JianliYang; JishengZhun; 等

    2001-01-01

    Catalyst plays an important role in direct cola liquefaction(DCL)[1],Due to relatively high activity,low cost and environmentally benign for disposal,iron catalysts are regarded as the most attractive catalysts for DCL.To maximize catalytic effect and minimize catalyst usage,ultra-fine size catalysts are preferred.The most effective catalysts are found to be those impregnated onto coal because of their high dispersion on coal surface and intimate contact with coal particles.

  10. STATE SPACE MODELING OF DIMENSIONAL MACHINING ERRORS OF SERIAL-PARALLEL HYBRID MULTI-STAGE MACHINING SYSTEM

    Institute of Scientific and Technical Information of China (English)

    XI Lifeng; DU Shichang

    2007-01-01

    The final product quality is determined by cumulation, coupling and propagation of product quality variations from all stations in multi-stage manufacturing systems (MMSs). Modeling and control of variation propagation is essential to improve product quality. However, the current stream of variations (SOV) theory can only solve the problem that a single SOV affects the product quality. Due to the existence of multiple variation streams, limited research has been done on the quality control in serial-parallel hybrid multi-stage manufacturing systems (SPH-MMSs). A state space model and its modeling strategies are developed to describe the multiple variation streams stack-up in an SPH-MMS. The SOV theory is extended to SPH-MMS. The dimensions of system model are reduced to the production-reality level, and the effect and feasibility of the model is validated by a machining case.

  11. FABRICATION OF MESSAGE DIGEST TO AUTHENTICATE AUDIO SIGNALS WITH ALTERNATION OF COEFFICIENTS OF HARMONICS IN MULTI-STAGES (MDAC

    Directory of Open Access Journals (Sweden)

    Uttam Kr. Mondal

    2011-11-01

    Full Text Available Providing security to audio songs for maintaining its intellectual property right (IPR is one of chanllenging fields in commercial world especially in creative industry. In this paper, an effective approach has been incorporated to fabricate authentication of audio song through application of message digest method with alternation of coefficients of harmonics in multi-stages of higher frequency domain without affecting its audible quality. Decomposing constituent frequency components of song signal using Fourier transform with generating secret code via applying message digest followed by alternating coefficients of specific harmonics in multi-stages generates a secret code and this unique code is utilized to detect the originality of the song. A comparative study has been made with similar existing techniques and experimental results are also supported with mathematical formula based on Microsoft WAVE (".wav" stereo sound file.

  12. Fabrication of Message Digest to Authenticate Audio Signals with Alternation of Coefficients of Harmonics in Multi-Stages (MDAC)

    CERN Document Server

    Mondal, Uttam Kr

    2012-01-01

    Providing security to audio songs for maintaining its intellectual property right (IPR) is one of chanllenging fields in commercial world especially in creative industry. In this paper, an effective approach has been incorporated to fabricate authentication of audio song through application of message digest method with alternation of coefficients of harmonics in multi-stages of higher frequency domain without affecting its audible quality. Decomposing constituent frequency components of song signal using Fourier transform with generating secret code via applying message digest followed by alternating coefficients of specific harmonics in multi-stages generates a secret code and this unique code is utilized to detect the originality of the song. A comparative study has been made with similar existing techniques and experimental results are also supported with mathematical formula based on Microsoft WAVE (".wav") stereo sound file.

  13. Fabrication of Message Digest to Authenticate Audio Signals with Alternation of Coefficients of Harmonics in Multi-Stages (MDAC

    Directory of Open Access Journals (Sweden)

    Uttam Kr. Mondal

    2011-12-01

    Full Text Available Providing security to audio songs for maintaining its intellectual property right (IPR is one ofchanllenging fields in commercial world especially in creative industry. In this paper, an effectiveapproach has been incorporated to fabricate authentication of audio song through application of messagedigest method with alternation of coefficients of harmonics in multi-stages of higher frequency domainwithout affecting its audible quality. Decomposing constituent frequency components of song signal usingFourier transform with generating secret code via applying message digest followed by alternatingcoefficients of specific harmonics in multi-stages generates a secret code and this unique code is utilized todetect the originality of the song. A comparative study has been made with similar existing techniques andexperimental results are also supported with mathematical formula based on Microsoft WAVE (".wav"stereo sound file.

  14. Dynamic-programming approaches to single-and multi-stage stochastic knapsack problems for portfolio optimization

    OpenAIRE

    Khoo, Wai Gea

    1999-01-01

    This thesis proposes new methods, based on dynamic programming, for solving certain single-stage and multi-stage integer stochastic knapsack problems. These problems model stochastic portfolio optimization problems (SPOPs) which assume deterministic unit weight, and normally distributed unit return with known mean and variance for each item type. Given an initial wealth, the objective is to select a portfolio that maximizes the probability of achieving or exceeding a specified final return th...

  15. 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...

  16. 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.

  17. Recording-based identification of site liquefaction

    Institute of Scientific and Technical Information of China (English)

    Hu Yuxian; Zhang Yushan; Liang Jianwen; Ray Ruichong Zhang

    2005-01-01

    Reconnaissance reports and pertinent research on seismic hazards show that liquefaction is one of the key sources of damage to geotechnical and structural engineering systems. Therefore, identifying site liquefaction conditions plays an important role in seismic hazard mitigation. One of the widely used approaches for detecting liquefaction is based on the time-frequency analysis of ground motion recordings, in which short-time Fourier transform is typically used. It is known that recordings at a site with liquefaction are the result of nonlinear responses of seismic waves propagating in the liquefied layers underneath the site. Moreover, Fourier transform is not effective in characterizing such dynamic features as time-dependent frequency of the recordings rooted in nonlinear responses. Therefore, the aforementioned approach may not be intrinsically effective in detecting liquefaction. An alternative to the Fourier-based approach is presented in this study,which proposes time-frequency analysis of earthquake ground motion recordings with the aid of the Hilbert-Huang transform (HHT), and offers justification for the HHT in addressing the liquefaction features shown in the recordings. The paper then defines the predominant instantaneous frequency (PIF) and introduces the PIF-related motion features to identify liquefaction conditions at a given site. Analysis of 29 recorded data sets at different site conditions shows that the proposed approach is effective in detecting site liquefaction in comparison with other methods.

  18. Effect of proton-conduction in electrolyte on electric efficiency of multi-stage solid oxide fuel cells.

    Science.gov (United States)

    Matsuzaki, Yoshio; Tachikawa, Yuya; Somekawa, Takaaki; Hatae, Toru; Matsumoto, Hiroshige; Taniguchi, Shunsuke; Sasaki, Kazunari

    2015-07-28

    Solid oxide fuel cells (SOFCs) are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Therefore, evolved technologies are required to achieve considerably higher electrical efficiencies. Here we present an innovative concept for a critically-high fuel-to-electricity conversion efficiency of up to 85% based on the lower heating value (LHV), in which a high-temperature multi-stage electrochemical oxidation is combined with a proton-conducting solid electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 76% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC).

  19. Optimization of Unbalanced Multi-stage Logistics Systems Based on Prüfer Number and Effective Capacity Coding

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Unbalanced multi-stage logistics systems are optimized using an improved genetic algorithm based on the Prüfer number and the effective capacity coding. The improved decoding procedure uses the node capacity of the logistics system as an important factor, which influences the decoding procedure. As a result, any Prüfer number produced stochastically can be decoded to a feasible logistics pattern, which matchs the node capacities of the logistics system. With effective capacity coding, an unbalanced logistics system can be converted to a set of balanced systems. The effective capacity coding was combined with the Prüfer number to construct the chromosome for the new method to search the whole solution space of the unbalanced multi-stage logistics system. Simulation results show that the new method finds a better solution with less computational time than st-GA. Although using a little more memory, the new method is still an efficient and robust method for optimizing unbalanced multi-stage logistics systems.

  20. Simplified Multi-Stage and Per Capita Convergence. An analysis of two climate regimes for differentiation of commitments

    Energy Technology Data Exchange (ETDEWEB)

    Den Elzen, M.G.J.; Berk, M.M.; Lucas, P.

    2004-07-01

    This report describes and analyses in detail two climate regimes for differentiating commitments: the simplified Multi-Stage and Per Capita Convergence approaches. The Multi-Stage approach consists of a system to divide countries into groups with different types of commitments (stages). The Per Capita Convergence defines emission permits on the basis of a convergence of per capita emissions. The analysis focuses on two global greenhouse gas emission profiles resulting in long-term CO2-equivalent concentrations stabilising at 550 and 650 ppmv (S550e and S650e profile). The abatement efforts (allocations) for Annex I regions for S550e for all variants generally range from 25%-50% below 1990 levels in 2025 and 70-85% in 2050. For S650e, these efforts range from 10% increase to 25% reduction in 2025 and 40-60% reduction in 2050. For non-Annex I regions, the results are generally more differentiated for the various commitment schemes, stabilization targets and time horizons than for Annex I regions. The analysis further highlights the major strengths and weakness of the Multi-Stage and Per Capita Convergence variants, and points at important obstacles and pre-conditions for their feasibility and acceptability.

  1. A risk-based interactive multi-stage stochastic programming approach for water resources planning under dual uncertainties

    Science.gov (United States)

    Wang, Y. Y.; Huang, G. H.; Wang, S.; Li, W.; Guan, P. B.

    2016-08-01

    In this study, a risk-based interactive multi-stage stochastic programming (RIMSP) approach is proposed through incorporating the fractile criterion method and chance-constrained programming within a multi-stage decision-making framework. RIMSP is able to deal with dual uncertainties expressed as random boundary intervals that exist in the objective function and constraints. Moreover, RIMSP is capable of reflecting dynamics of uncertainties, as well as the trade-off between the total net benefit and the associated risk. A water allocation problem is used to illustrate applicability of the proposed methodology. A set of decision alternatives with different combinations of risk levels applied to the objective function and constraints can be generated for planning the water resources allocation system. The results can help decision makers examine potential interactions between risks related to the stochastic objective function and constraints. Furthermore, a number of solutions can be obtained under different water policy scenarios, which are useful for decision makers to formulate an appropriate policy under uncertainty. The performance of RIMSP is analyzed and compared with an inexact multi-stage stochastic programming (IMSP) method. Results of comparison experiment indicate that RIMSP is able to provide more robust water management alternatives with less system risks in comparison with IMSP.

  2. A multi-stage 3-D stress field modelling approach exemplified in the Bavarian Molasse Basin

    Science.gov (United States)

    Ziegler, Moritz O.; Heidbach, Oliver; Reinecker, John; Przybycin, Anna M.; Scheck-Wenderoth, Magdalena

    2016-09-01

    The knowledge of the contemporary in situ stress state is a key issue for safe and sustainable subsurface engineering. However, information on the orientation and magnitudes of the stress state is limited and often not available for the areas of interest. Therefore 3-D geomechanical-numerical modelling is used to estimate the in situ stress state and the distance of faults from failure for application in subsurface engineering. The main challenge in this approach is to bridge the gap in scale between the widely scattered data used for calibration of the model and the high resolution in the target area required for the application. We present a multi-stage 3-D geomechanical-numerical approach which provides a state-of-the-art model of the stress field for a reservoir-scale area from widely scattered data records. Therefore, we first use a large-scale regional model which is calibrated by available stress data and provides the full 3-D stress tensor at discrete points in the entire model volume. The modelled stress state is used subsequently for the calibration of a smaller-scale model located within the large-scale model in an area without any observed stress data records. We exemplify this approach with two-stages for the area around Munich in the German Molasse Basin. As an example of application, we estimate the scalar values for slip tendency and fracture potential from the model results as measures for the criticality of fault reactivation in the reservoir-scale model. The modelling results show that variations due to uncertainties in the input data are mainly introduced by the uncertain material properties and missing SHmax magnitude estimates needed for a more reliable model calibration. This leads to the conclusion that at this stage the model's reliability depends only on the amount and quality of available stress information rather than on the modelling technique itself or on local details of the model geometry. Any improvements in modelling and increases

  3. NDDP multi-stage flash desalination process simulator design process optimization

    International Nuclear Information System (INIS)

    The improvement of NDDP-MSF plant's performance ratio (PR) from design value of 9.0 to 13.1 was achieved by optimizing the plant's operating parameters within the feasible zone of operation. This plant has 20% excess heat transfer area over the design condition which helped us to get a PR of 15.1 after optimization. Thus we have obtained, (1) A 45% increase in the output over design value by the optimization carried out with design heat transfer area. (2) A 68% increase in the output over design value by the optimization carried out with increased heat transfer area. This report discusses the approach, methodology and results of the optimization study carried out. A simulator, MSFSIM which predicts the performance of a multi-stage flash (MSF) desalination plant has been coupled with Genetic Algorithm (GA) optimizer. Exhaustive optimization case studies have been conducted on this plant with an objective to increase the performance ratio (PR). The steady state optimization performed was based on obtaining the best stage wise pressure profile to enhance thermal efficiency which in-turn improves the performance ratio. Apart from this, the recirculating brine flow rate was also optimized. This optimization study enabled us to increase the PR of NDDP-MSF plant from design value of 9.0 to an optimized value 13.1. The actual plant is provided with 20% additional heat transfer area over and above the design heat transfer area. Optimization with this additional heat transfer area has taken the PR to 15.1. A desire to maintain equal flashing rates in all of the stages (a feature required for long life of the plant and to avoid cascading effect of non-flashing triggered by any stage) of the MSF plant has also been achieved. The deviation in the flashing rates within stages has been reduced. The startup characteristic of the plant (i.e the variation of stage pressure and the variation of recirculation flow rate with time), have been optimized with a target to minimize the

  4. Validation of multi-stage telephone-based identification of cognitive impairment and dementia

    Directory of Open Access Journals (Sweden)

    Chui Helena

    2005-04-01

    Full Text Available Abstract Background Many types of research on dementia and cognitive impairment require large sample sizes. Detailed in-person assessment using batteries of neuropyschologic testing is expensive. This study evaluates whether a brief telephone cognitive assessment strategy can reliably classify cognitive status when compared to an in-person "gold-standard" clinical assessment. Methods The gold standard assessment of cognitive status was conducted at the University of Southern California Alzheimer Disease Research Center (USC ADRC. It involved an examination of patients with a memory complaint by a neurologist or psychiatrist specializing in cognitive disorders and administration of a battery of neuropsychologic tests. The method being evaluated was a multi-staged assessment using the Telephone Interview of Cognitive Status-modified (TICSm with patients and the Telephone Dementia Questionnaire (TDQ with a proxy. Elderly male and female patients who had received the gold standard in-person assessment were asked to also undergo the telephone assessment. The unweighted kappa statistic was calculated to compare the gold standard and the multistage telephone assessment methods. Sensitivity for classification with dementia and specificity for classification as normal were also calculated. Results Of 50 patients who underwent the gold standard assessment and were referred for telephone assessment, 38 (76% completed the TICS. The mean age was 78.1 years and 26 (68% were female. When comparing the gold standard assessment and the telephone method for classifying subjects as having dementia or no dementia, the sensitivity of the telephone method was 0.83 (95% confidence interval 0.36, 1.00, the specificity was 1.00 (95% confidence interval 0.89,1.00. Kappa was 0.89 (95% confidence interval 0.69, 1.000. Considering a gold-standard assessment of age-associated memory impairment as cognitive impairment, the sensitivity of the telephone approach is 0.38 (95

  5. A Multi-Stage Wear Model for Grid-to-Rod Fretting of Nuclear Fuel Rods

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter Julian [ORNL

    2014-01-01

    The wear of fuel rod cladding against the supporting structures in the cores of pressurized water nuclear reactors (PWRs) is an important and potentially costly tribological issue. Grid-to-rod fretting (GTRF), as it is known, involves not only time-varying contact conditions, but also elevated temperatures, flowing hot water, aqueous tribo-corrosion, and the embrittling effects of neutron fluences. The multi-stage, closed-form analytical model described in this paper relies on published out-of-reactor wear and corrosion data and a set of simplifying assumptions to portray the conversion of frictional work into wear depth. The cladding material of interest is a zirconium-based alloy called Zircaloy-4, and the grid support is made of a harder and more wear-resistant material. Focus is on the wear of the cladding. The model involves an incubation stage, a surface oxide wear stage, and a base alloy wear stage. The wear coefficient, which is a measure of the efficiency of conversion of frictional work into wear damage, can change to reflect the evolving metallurgical condition of the alloy. Wear coefficients for Zircaloy-4 and for a polyphase zirconia layer were back-calculated for a range of times required to wear to a critical depth. Inputs for the model, like the friction coefficient, are taken from the tribology literature in lieu of in-reactor tribological data. Concepts of classical fretting were used as a basis, but are modified to enable the model to accommodate the complexities of the PWR environment. Factors like grid spring relaxation, pre-oxidation of the cladding, multiple oxide phases, gap formation, impact, and hydrogen embrittlement are part of the problem definition but uncertainties in their relative roles limits the ability to validate the model. Sample calculations of wear depth versus time in the cladding illustrate how GTRF wear might occur in a discontinuous fashion during months-long reactor operating cycles. A means to account for grid/rod gaps

  6. Catalytic coal liquefaction with treated solvent and SRC recycle

    Science.gov (United States)

    Garg, Diwakar; Givens, Edwin N.; Schweighardt, Frank K.

    1986-01-01

    A process for the solvent refining of coal to distillable, pentane soluble products using a dephenolated and denitrogenated recycle solvent and a recycled, pentane-insoluble, solvent-refined coal material, which process provides enhanced oil-make in the conversion of coal.

  7. Kinetics assisted design of catalysts for coal liquefaction. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Klein, M.T.; Foley, H.C.; Calkins, W.H.; Scouten, C.

    1998-02-01

    The thermal and catalytic reactions of 4-(1-naphthylmethyl)bibenzyl (NBBM), a resid and coal model compound, were examined. Catalytic reaction of NBBM was carried out at 400 C under hydrogen with a series of transition metal-based catalytic materials including Fe(CO){sub 4}PPh{sub 3}, Fe(CO){sub 3}(PPh{sub 3}){sub 2}, Fe(CO){sub 2}(PPh{sub 3}){sub 2}CS{sub 2}, Fe(CO){sub 5}, Mo(CO){sub 6}, Mn{sub 2}(CO){sub 10}, Fe{sub 2}O{sub 3} and MoS{sub 2}. Experimental findings and derived mechanistic insights were organized into molecular-level reaction models for NBBM pyrolysis and catalysis. Hydropyrolysis and catalysis reaction families occurring during NBBM hydropyrolysis at 420 C were summarized in the form of reaction matrices which, upon exhaustive application to the components of the reacting system, yielded the mechanistic reaction model. Each reaction family also had an associated linear free energy relationship (LFER) which provided an estimate of the rate constant k{sub i} given a structural property of species i or its reaction. Including the catalytic reaction matrices with those for the pyrolysis model provided a comprehensive NBBM catalytic reaction model and allowed regression of fundamental LFER parameters for the catalytic reaction families. The model also allowed specification of the property of an optimal catalyst. Iron, molybdenum and palladium were predicted to be most effective for model compound consumption. Due to the low costs associated with iron and its disposal, it is a good choice for coal liquefaction catalysis and the challenge remains to synthesize small particles able to access the full surface area of the coal macromolecule.

  8. 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.

  9. Preparation of mesoporous activated carbons from coal liquefaction residue for methane decomposition

    Institute of Scientific and Technical Information of China (English)

    Jianbo Zhang; Lijun Jin; Shengwei Zhu; Haoquan Hu

    2012-01-01

    Mesoporous activated carbons were prepared from direct coal liquefaction residue (CLR) by KOH activation method,and the experiments were carried out to investigate the effects of KOH/CLR ratio,solvent for mixing the CLR and KOH,and carbonization procedure on the resultant carbon texture and catalytic activity for catalytic methane decomposition (CMD).The results showed that optimal KOH/CLR ratio of 2 ∶ 1;solvent with higher solubility to KOH or the CLR,and an appropriate carbonization procedure are conductive to improving the carbon pore structure and catalytic activity for CMD.The resultant mesoporous carbons show higher and more stable activity than microporous carbons.Additionally,the relationship between the carbon textural properties and the catalytic activity for CMD was also discussed.

  10. Turnkey Helium Purification and Liquefaction Plant for DARWIN, Australia

    Science.gov (United States)

    Lindemann, U.; Boeck, S.; Blum, L.; Kurtcuoglu, K.

    2010-04-01

    The Linde Group, through its Australian subsidiary BOC Limited, has signed an agreement with Darwin LNG Pty Ltd for the supply of feed-gas to Linde's new helium refining and liquefaction facility in Darwin, Australia. Linde Kryotechnik AG, located in Switzerland, has carried out the engineering and fabrication of the equipment for the turn key helium plant. The raw feed gas flow of 20'730 Nm3/h contains up to of 3 mol% helium. The purification process of the feed gas consists of partial condensation of nitrogen in two stages, cryogenic adsorption and finally catalytic oxidation of hydrogen followed by a dryer system. Downstream of the purification the refined helium is liquefied using a modified Bryton process and stored in a 30'000 gal LHe tank. For further distribution and export of the liquid helium there are two stations available for filling of truck trailers and containers. The liquid nitrogen, required for refrigeration capacity to the nitrogen removal stages in the purification process as well as for the pre-cooling of the pure helium in the liquefaction process, is generated on site during the feed gas purification process. The optimized process provides low power consumption, maximum helium recovery and a minimum helium loss.

  11. 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.

  12. Liquefaction of crop residues for polyol production

    Directory of Open Access Journals (Sweden)

    Wan, C.

    2006-11-01

    Full Text Available The liquefaction of crop residues in the presence of ethylene glycol, ethylene carbonate, or polyethylene glycol using sulfuric acid as a catalyst was studied. For all experiments, the liquefaction was conducted at 160C and atmospheric pressure. The mass ratio of feedstock to liquefaction solvents used in all the experiments was 30:100. The results show that the acid catalyzed liquefaction process fit a pseudo-first-order kinetics model. Liquefaction yields of 80, 74, and 60% were obtained in 60 minutes of reaction when corn stover was liquefied with ethylene glycol, a mixture of polyethylene glycol and glycerol (9:1, w/w, and ethylene carbonate, respectively. When ethylene carbonate was used as solvent, the liquefaction yields of rice straw and wheat straw were 67% and 73%, respectively, which is lower than that of corn stover (80%. When a mixture of ethylene carbonate and ethylene glycol (8:2, w/w was used as solvent, the liquefaction yields for corn stover, rice straw and wheat straw were 78, 68, and 70%, respectively.

  13. Earthquake-induced liquefaction in Ferland, Quebec

    International Nuclear Information System (INIS)

    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

  14. REVIEW OF NATURAL GAS LIQUEFACTION PROCESSES

    Directory of Open Access Journals (Sweden)

    Katarina Simon

    2009-12-01

    Full Text Available High pressure pipelines are the most common way of natural gas transport from a gas field to a processing plant and further to consumers. In case when the distance between natural gas production and consumption regions is more than 4000 kilometers, and due to necessity of natural gas supply diversification, gas liquefaction and its transport by ships is being applied. The final choice of liquefaction process depends on the project variables, the development level of new or upgrading of already existing processes and available equipment. Current natural gas liquefaction processes and their usage in practice are shown in this paper (the paper is published in Croatian.

  15. 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.

  16. Cooperative research program in coal liquefaction. Quarterly report, August 1, 1991--October 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Huffman, G.P. [ed.

    1991-12-31

    This Quarterly Report on coal liquefaction research includes discussion in the areas of (1) Iron Based Catalysts for Coal Liquefaction; (2) Exploratory Research on Coal Conversion; (3) Novel Coal Liquefaction Concepts; (4) Novel Catalysts for Coal Liquefaction. (VC)

  17. Cooperative Research Program in coal liquefaction. Technical report, May 1, 1994--October 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    Progress reports 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.

  18. Coal liquefaction. Quarterly report, July--September 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-02-01

    ERDA's program for the conversion of coal to liquid fuels is aimed at improved process configurations for both catalytic and noncatalytic processes to provide more attractive processing economics and lower capital investment. The advantage of coal liquefaction is that the entire range of liquid products, including heavy boiler fuel, distillate fuel oil, gasoline, jet fuel, and diesel oil, can be produced from coal by varying the type of process and operating conditions used in the process. Furthermore, coal-derived liquids also have the potential for use as chemical feedstocks. To provide efficient and practical means of utilizing coal resources, ERDA is sponsoring the development of several conversion processes that are currently in the pilot plant stage. Responsibility for the design, construction, and operation of these facilities is given and progress in the quarter is summarized. Several supporting or complementary projects are described similarly. (LTN)

  19. Direct coal liquefaction baseline design and system analysis

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The primary objective of the study is to develop a computer model for a base line direct coal liquefaction design based on two stage direct coupled catalytic reactors. This primary objective is to be accomplished by completing the following: a base line design based on previous DOE/PETC results from Wilsonville pilot plant and other engineering evaluations; a cost estimate and economic analysis; a computer model incorporating the above two steps over a wide range of capacities and selected process alternatives; a comprehensive training program for DOE/PETC Staff to understand and use the computer model; a thorough documentation of all underlying assumptions for baseline economics; and a user manual and training material which will facilitate updating of the model in the future.

  20. Coal liquefaction. Quarterly report, October-December 1978

    Energy Technology Data Exchange (ETDEWEB)

    1979-09-01

    DOE's program for the conversion of coal to liquid fuels was begun by two of DOE's predecessor agencies: Office of Coal Research (OCR) in 1962, and ERDA. The Bureau of Mines, US Department of the Interior, had started work in the 1930's. Current work is aimed at improved process configurations for both catalytic and noncatalytic processes to provide more attractive processing economics and lower capital investment. The advantage of coal liquefaction is that the entire range of liquid products, especially boiler fuel, distillate fuel oil, and gasoline, can be produced from coal by varying the type of process and operating conditions used in the process. Furthermore, coal-derived liquids have the potential for use as chemical feedstocks. To provide efficient and practical means of utilizing coal resources, DOE is supporting the development of several conversion processes that are currently in the pilot plant stage. Each of these processes are described briefly.

  1. Determination of rational design parameters of a multi-stage solar water desalination still using transient mathematical modelling

    Energy Technology Data Exchange (ETDEWEB)

    Shatat, M.I.M.; Mahkamov, K. [School of Engineering, Durham University, South Road, Durham, DH1 3LE (United Kingdom)

    2010-01-15

    The paper describes the experimental investigations of the performance of a multi-stage water desalination still connected to a heat pipe evacuated tube solar collector with aperture area of 1.7 m{sup 2}. The multi-stage solar still water desalination system was designed to recover latent heat from evaporation and condensation processes in four stages. The variation in the solar radiation during a typical mid-summer day in the Middle East region was simulated on the test rig using an array of 110 halogen floodlights covering the area of the collector. The results of tests demonstrate that the system produces about 9 kg of fresh water per day and has a solar collector efficiency of about 68%. However, the overall efficiency of the laboratory test rig at this stage of the investigations was found to be at the level of 33% due to excessive heat losses in the system. The analysis of the distilled water showed that its quality was within the World Health Organization guidelines. The still's operation was numerically simulated by employing a mathematical model based on a system of ordinary energy and mass conservation differential equations written for each stage of the still. A computer program was developed for transient simulations of the evaporation and condensation processes inside the multi-stage still. Experimental results obtained and theoretical predictions were found to be in good agreement. The results on the determination of rational design dimensions and number of stages of the still for a given aperture of the solar collector are also presented in this work. (author)

  2. Multi-stage crustal growth and cratonization of the North China Craton

    Institute of Scientific and Technical Information of China (English)

    Mingguo Zhai

    2014-01-01

    The North China Craton (NCC) has a complicated evolutionary history with multi-stage crustal growth, recording nearly all important geological events in the early geotectonic history of the Earth. Our studies propose that the NCC can be divided into six micro-blocks with >w3.0e3.8 Ga old continental nuclei that are surrounded by Neoarchean greenstone belts (GRB). The micro-blocks are also termed as high-grade regions (HGR) and are mainly composed of orthogneisses with minor gabbros and BIF-bearing supracrustal beds or lenses, all of which underwent strong deformation and metamorphism of granu-lite-to high-grade amphibolite-facies. The micro-blocks are, in turn, from east to west, the Jiaoliao (JL), Qianhuai (QH), Ordos (ODS), Ji’ning (JN) and Alashan (ALS) blocks, and Xuchang (XCH) in the south. Recent studies led to a consensus that the basement of the NCC was composed of different blocks/ter-ranes that were finally amalgamated to form a coherent craton at the end of Neoarchean. Zircon U-Pb data show that TTG gneisses in the HGRs have two prominent age peaks at ca. 2.9e2.7 and 2.6e2.5 Ga which may correspond to the earliest events of major crustal growth in the NCC. Hafnium isotopic model ages range from ca. 3.8 to 2.5 Ga and mostly are in the range of 3.0e2.6 Ga with a peak at 2.82 Ga. Recent studies revealed a much larger volume of TTG gneisses in the NCC than previously considered, with a dominant ca. 2.7 Ga magmatic zircon ages. Most of the ca. 2.7 Ga TTG gneisses un-derwent metamorphism in 2.6e2.5 Ga as indicated by ubiquitous metamorphic rims around the cores of magmatic zircon in these rocks. Abundant ca. 2.6e2.5 Ga orthogneisses have Hf-in-zircon and Nd whole-rock model ages mostly around 2.9e2.7 Ga and some around 2.6e2.5 Ga, indicating the timing of pro-tolith formation or extraction of the protolith magma was from the mantle. Therefore, it is suggested that the 2.6e2.5 Ga TTGs probably represent a coherent event of continental accretion and major

  3. 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.

  4. Progress in Coal Liquefaction Technologies

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Worldwide primary energy consumption is entering an era of pluralism and high quality under the influence of rapid economic development, increasing energy shortage and strict environmental policies. Although renewable energy technology is developing rapidly, fossil fuels (coal, oil and gas) are still the dominant energy sources in the world. As a country rich in coal but short ofoil and gas, China's oil imports have soared in the past few years. Government, research organizations and enterprises in China are paying more and more attention to the processes of converting coal into clean liquid fuels. Direct and indirect coal liquefaction technologies are compared in this paper based on China's current energy status and technological progress not only in China itself but also in the world.

  5. Performance assessment and microbial diversity of two pilot scale multi-stage sub-surface flow constructed wetland systems.

    Science.gov (United States)

    Babatunde, A O; Miranda-CasoLuengo, Raul; Imtiaz, Mehreen; Zhao, Y Q; Meijer, Wim G

    2016-08-01

    This study assessed the performance and diversity of microbial communities in multi-stage sub-surface flow constructed wetland systems (CWs). Our aim was to assess the impact of configuration on treatment performance and microbial diversity in the systems. Results indicate that at loading rates up to 100gBOD5/(m(2)·day), similar treatment performances can be achieved using either a 3 or 4 stage configuration. In the case of phosphorus (P), the impact of configuration was less obvious and a minimum of 80% P removal can be expected for loadings up to 10gP/(m(2)·day) based on the performance results obtained within the first 16months of operation. Microbial analysis showed an increased bacterial diversity in stage four compared to the first stage. These results indicate that the design and configuration of multi-stage constructed wetland systems may have an impact on the treatment performance and the composition of the microbial community in the systems, and such knowledge can be used to improve their design and performance. PMID:27521934

  6. Studies of the impact of prerotation problem of the secondary impeller on performance of multi-stage centrifugal pumps

    International Nuclear Information System (INIS)

    In engineering practice, part of the multi-stage centrifugal pumps is designed without space guide vanes due to the size restrictions and the volute is distorted much in shape. In these pumps, tangential velocity of the fluid at the outlet of the first-stage impeller is so great that it has caused a prerotation problem which will affect the inlet flow conditions of the secondary impeller leading to serious efficiency and head decline of the secondary impeller. The head problem of the second stage in multi-stage centrifugal pumps caused by prerotation at the entrance of the second stage was analyzed and the internal hydraulic performance was optimized by setting clapboards in the volute in this paper. CFD numerical simulation method combined with experiment was applied to predict the effect of internal clapboards on the performance of the centrifugal pump. The original prototype was transformed according to the simulation result and tested to verify the optimization work. The experiment result shows that hydraulic performance is remarkably improved compared with the original one and the prerotation problem is basically solved.

  7. Application of multi-stage, multi-disk type downhole seismic source; Tadanshiki taso enbangata koseinai shingen no tekiyosei

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, N. [Japan National Oil Corp., Tokyo (Japan); Shoji, Y. [Oyo Corp., Tokyo (Japan)

    1997-05-27

    A multi-stage, multi-disk type seismic source was developed as a downhole seismic source. The seismic source is an improved version of the downhole seismic source of a system in which an elastic wave is generated by a weight accelerated by restitutive force of a spring striking the upper part of a laminated structure consisted of metal disks and elastic bodies installed in water in a well. Enhancing the vibration exciting efficiency requires impedance radiated from the disks to be increased. The multi-disk structure was adopted because of restrictions on the disk area under the limiting condition of being inside the well. Further limitation has still existed, which led to finally structuring the multi-disk type to a multi-stage construction to increase the radiated impedance. In order to increase average velocity on the radiation surface, mass relationship between the hammer and the anvil was sought so that the maximum velocity is achieved at the process of converting motion energies among the hammer, anvil and disks. The anvil mass may sufficiently be 50% to 100% of the hammer mass. The equipment was installed in an actual oil well for testing. This seismic source was verified to have sufficient applicability in the cross hole measurement. 5 refs., 7 figs., 1 tab.

  8. Optimum design of multi-layer K-edge filter and multi-stage detectors for triple energy bone densitometer

    Science.gov (United States)

    Mazoochi, Alireza; Rahmani, Faezeh; Abbasi Davani, Fereydoun; Ghaderi, Ruhollah

    2014-03-01

    Dual X-ray bone densitometry may cause some errors in diagnosis due to heterogeneous distribution of adipose tissue. It is necessary to develop a more accurate technique to consider the effects of fat. In this research, a triple energy X-ray method has been introduced and conceptual design of a system consisting of 160 kV X-ray tube, multi-layer K-edge filter and multi-stage detector has been presented. Design calculations have been performed using MCNP4C Monte Carlo code to select the type of filters and detectors with the best thicknesses for better distinguishing materials. The energy peaks (37 keV, 50 keV and 105 keV) can be separated optimally with a multi-layer filter composed of barium (170 μm) and gadolinium (100 μm) as the first and second layers, respectively which are coated on a 1 mm aluminum plate placed between the source and tissue. The transmitted photons have been counted by a multi-stage linear array of detectors consisting of ZnSe(Te) and CsI(Tl) with 400 μm and 5 mm thicknesses, respectively. Monte Carlo simulations show that the triple energy X-ray technique has better accuracy than that of the standard dual energy X-ray technique.

  9. Multi-Stage Control of Waste Heat Recovery from High Temperature Slags Based on Time Temperature Transformation Curves

    Directory of Open Access Journals (Sweden)

    Yongqi Sun

    2014-03-01

    Full Text Available This paper presents a significant method and a basic idea of waste heat recovery from high temperature slags based on Time Temperature Transformation (TTT curves. Three samples with a fixed CaO/SiO2 ratio of 1.05 and different levels of Al2O3 were designed and isothermal experiments were performed using a Single Hot Thermocouple Technique (SHTT. The TTT curves established through SHTT experiments described well the variation of slag properties during isothermal processes. In this study, we propose a multi-stage control method for waste heat recovery from high temperature slags, in which the whole temperature range from 1500 °C to 25 °C was divided into three regions, i.e., Liquid region, Crystallization region and Solid region, based on the TTT curves. Accordingly, we put forward an industrial prototype plant for the purpose of waste heat recovery and the potential of waste heat recovery was then calculated. The multi-stage control method provided not only a significant prototype, but also a basic idea to simultaneously extract high quality waste heat and obtain glassy phases on high temperature slags, which may fill the gap between slag properties and practical waste heat recovery processes.

  10. 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.

  11. 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.

  12. Coal liquefaction and gas conversion: Proceedings. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    Volume II contains papers presented at the following sessions: Indirect Liquefaction (oxygenated fuels); and Indirect Liquefaction (Fischer-Tropsch technology). Selected papers have been processed separately for inclusion in the Energy Science and Technology Database.

  13. 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.

  14. Coal liquefaction process research quarterly report, October-December 1979

    Energy Technology Data Exchange (ETDEWEB)

    Bickel, T.C.; Curlee, R.M.; Granoff, B.; Stohl, F.V.; Thomas, M.G.

    1980-03-01

    This quarterly report summarizes the activities of Sandia's continuing program in coal liquefaction process research. The overall objectives are to: (1) provide a fundamental understanding of the chemistry of coal liquefaction; (2) determine the role of catalysts in coal liquefaction; and (3) determine the mechanism(s) of catalyst deactivation. The program is composed of three major projects: short-contact-time coal liquefaction, mineral effects, and catalyst studies. These projects are interdependent and overlap significantly.

  15. Estimation of sand liquefaction based on support vector machines

    Institute of Scientific and Technical Information of China (English)

    苏永华; 马宁; 胡检; 杨小礼

    2008-01-01

    The origin and influence factors of sand liquefaction were analyzed, and the relation between liquefaction and its influence factors was founded. A model based on support vector machines (SVM) was established whose input parameters were selected as following influence factors of sand liquefaction: magnitude (M), the value of SPT, effective pressure of superstratum, the content of clay and the average of grain diameter. Sand was divided into two classes: liquefaction and non-liquefaction, and the class label was treated as output parameter of the model. Then the model was used to estimate sand samples, 20 support vectors and 17 borderline support vectors were gotten, then the parameters were optimized, 14 support vectors and 6 borderline support vectors were gotten, and the prediction precision reaches 100%. In order to verify the generalization of the SVM method, two other practical samples’ data from two cities, Tangshan of Hebei province and Sanshui of Guangdong province, were dealt with by another more intricate model for polytomies, which also considered some influence factors of sand liquefaction as the input parameters and divided sand into four liquefaction grades: serious liquefaction, medium liquefaction, slight liquefaction and non-liquefaction as the output parameters. The simulation results show that the latter model has a very high precision, and using SVM model to estimate sand liquefaction is completely feasible.

  16. 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.

  17. Coal liquefaction. Quarterly report, April-June 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-04-01

    DOE's program for the conversion of coal to liquid fuels was begun by two of DOE's predecessor agencies: Office of Coal Research (OCR) in 1962, and Bureau of Mines, US Department of the Interior, in the 1930's. Current work is aimed at improved process configurations for both catalytic and non-catalytic processes to provide more attractive processing economics and lower capital investment. The advantage of coal liquefaction is that the entire range of liquid products, especially boiler fuel, distillate fuel oil, and gasoline, can be produced from coal by varying the type of process and operating conditions used in the process. Furthermore, coal-derived liquids have the potential for use as chemical feedstocks. To provide efficient and practical means of utilizing coal resources, DOE is supporting the development of several conversion processes that are currently in the pilot plant stage. DOE, together with the Electric Power Research Institue, has contracted with fourteen projects are described brieflly: funding, description, status, history, and progress in the current quarter. (LTN)

  18. Optimization of Realistic Multi-Stage Hybrid Flow Shop Scheduling Problems with Missing Operations Using Meta-Heuristics

    Directory of Open Access Journals (Sweden)

    M. Saravanan

    2014-03-01

    Full Text Available A Hybrid flow shop scheduling is characterized ‘n’ jobs ‘m’ machines with ‘M’ stages by unidirectional flow of work with a variety of jobs being processed sequentially in a single-pass manner. The paper addresses the multi-stage hybrid flow shop scheduling problems with missing operations. It occurs in many practical situations such as stainless steel manufacturing company. The essential complexity of the problem necessitates the application of meta-heuristics to solve hybrid flow shop scheduling. The proposed Simulated Annealing algorithm (SA compared with Particle Swarm Optimization (PSO with the objective of minimization of makespan. It is show that the SA algorithm is efficient in finding out good quality solutions for the hybrid flow shop problems with missing operations.

  19. Study on the hot deformation behavior of Al-Zn-Mg-Cu-Craluminum alloy during multi-stage hot compression

    Institute of Scientific and Technical Information of China (English)

    Gaoyong LIN; Xiaoyan ZHENG; Wei YANG; Di FENG; Dashu PENG

    2009-01-01

    The mechanical behavior and microstructures of an Al-Zn-Mg-Cu-Cr aluminum alloy during multi-stage hot deformation were investigated by thermal stimulation test, optical microscopy, and transmission electron microscopy. The true stress vs true strain curves and the microstructure evolution of two hot deformation procedures were gained. The flow stress of the alloy studied decreases with increasing the deforming passes and declining the temperature, and the larger the temperature decline between adjacent stages, the larger the peak stress fall is. The stress-strain behavior mainly result from the dynamic recovery during deformation, the static recovery and re-crystallization in the delay time, and the second phases precipitated from the matrix at high temperature.

  20. Multi-stage FEL amplifier with diaphragm focusing line as direct energy driver for inertial confinement fusion

    International Nuclear Information System (INIS)

    An FEL based energy driver for Inertial Confinement Fusion (ICF) is proposed. The key element of the scheme is free electron laser system. Novel technical solutions, namely, using of multichannel, multi-stage FEL amplifier with diaphragm focusing line, reveal a possibility to construct the FEL system operating at radiation wavelength λ = 0.5 μm and providing flush energy E = 1 MJ and brightness 4 x 1022 W cm-2 sr-1 within steering pulse duration τ ∼ 0.1-2 ns. Total energy efficiency of the proposed ICF energy driver is about of 11% and repetition rate is 40 Hz. It is shown that the FEL based ICF energy driver may be constructed at the present level of accelerator technique R ampersand D

  1. Modular Adaptive System Based on a Multi-Stage Neural Structure for Recognition of 2D Objects of Discontinuous Production

    Directory of Open Access Journals (Sweden)

    I. Topalova

    2008-11-01

    Full Text Available This is a presentation of a new system for invariant recognition of 2D objects with overlapping classes, that can not be effectively recognized with the traditional methods. The translation, scale and partial rotation invariant contour object description is transformed in a DCT spectrum space. The obtained frequency spectrums are decomposed into frequency bands in order to feed different BPG neural nets (NNs. The NNs are structured in three stages - filtering and full rotation invariance; partial recognition; general classification. The designed multi-stage BPG Neural Structure shows very good accuracy and flexibility when tested with 2D objects used in the discontinuous production. The reached speed and the opportunuty for an easy restructuring and reprogramming of the system makes it suitable for application in different applied systems for real time work.

  2. Flexible Design and Operation of Multi-Stage Flash (MSF Desalination Process Subject to Variable Fouling and Variable Freshwater Demand

    Directory of Open Access Journals (Sweden)

    Said Alforjani Said

    2013-10-01

    Full Text Available This work describes how the design and operation parameters of the Multi-Stage Flash (MSF desalination process are optimised when the process is subject to variation in seawater temperature, fouling and freshwater demand throughout the day. A simple polynomial based dynamic seawater temperature and variable freshwater demand correlations are developed based on actual data which are incorporated in the MSF mathematical model using gPROMS models builder 3.0.3. In addition, a fouling model based on stage temperature is considered. The fouling and the effect of noncondensable gases are incorporated into the calculation of overall heat transfer co-efficient for condensers. Finally, an optimisation problem is developed where the total daily operating cost of the MSF process is minimised by optimising the design (no of stages and the operating (seawater rejected flowrate and brine recycle flowrate parameters.

  3. Evaluation of the Stability and Performance of a Multi-Stage Riemann Solver in Relativistic Hydrodynamic Simulations

    CERN Document Server

    Sikorski, J; Kikoła, D; Słodkowski, M; Aszklar, P

    2015-01-01

    The work deals with assessing the quality of a multi-stage Riemann solver for relativistic hydrodynamic simulations of heavy-ion collisions. The physical system is described using hydrodynamic conservation laws and then solved numerically. Because of the nature of such hydrodynamic simulations the numerical method has to cope with problems containing both strong discontinuities and smooth solutions, and reproduce these features with a high precision and stability. Moreover, to verify the correctness of the proposed physical model, a massive number of simulations with a high spatial resolution is needed. Due to the high numerical cost, a highly e?cient implementation for solving such large-scale problems is required. The MUSTA-FORCE algorithm is a universal tool for hydrodynamic simulations. It uses simple central schemes and does not require any knowledge of the physical process's details, thus it can be used for virtually any physical system. We investigate the application of the MUSTA-FORCE scheme for relat...

  4. PATIENT-CENTRED SCREENING FOR PRIMARY IMMUNODEFICIENCY, A MULTI-STAGE DIAGNOSTIC PROTOCOL DESIGNED FOR NONIMMUNOLOGISTS: 2011 UPDATE

    Directory of Open Access Journals (Sweden)

    E. de Vries

    2013-01-01

    Full Text Available Abstract. Members of the European Society for Immunodeficiencies (ESID and other colleagues have updated themulti-stage expert-opinion-based diagnostic protocol for non-immunologists incorporating newly defined primary immunodeficiency diseases (PIDs. The protocol presented here aims to increase the awareness of PIDs among doctors working in different fields. Prompt identification of PID is important for prognosis, but this may not be an easy task. The protocol therefore starts from the clinical presentation of the patient. Because PIDs may present at all ages, this protocol is aimed at both adult and paediatric physicians. The multi-stage design allows cost-effective screening for PID of the large number of potential cases in the early phases, with more expensive tests reserved for definitive classification in collaboration with a specialist in the field of immunodeficiency at a later stage.

  5. Evidence of Multi-Stage Hydrocarbon Charging and Biodegradation of the Silurian Asphaltic Sandstones in the Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    刘洛夫

    2002-01-01

    Asphalts distributed widely in the Silurian sandstones of the Tarim Basin include dry asphalt, soft asphalt and heavy oil. These asphaltic sandstones underwent multi-episodic sedimentary and tectonic events, and their occurrence is diverse and complex, being mixed with normal oil usually. So far, very little work has been done on the asphaltic sandstone origin and hydrocarbon charging ages. After detailed study on the Silurian sandstones, the following highlights were obtained from the analytical results: distribution of the mixed asphalt, heavy oil and normal oil in the Silurian sandstones is the result of multi-stage hydrocarbon charging from the Lower Paleozoic marine source rocks; the characters of asphalts formed from oils of different charging ages are of difference; the most important process constraining.the asphaltic sandstone origin is thought to be biodegradation.

  6. Study of catalytic effects of mineral matter level on coal reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Mazzocco, Nestor J.; Klunder, Edgar B.; Krastman, Donald

    1981-03-01

    Coal liquefaction experiments using a 400-lb/day bubble-column reactor tested the catalytic effects of added mineral matter level on coal conversion, desulfurization, and distillate yields in continuous operation under recycle conditions, with specific emphasis on the use of a disposable pyrite catalyst indigenous to the feed coal. Western Kentucky No. 11 run-of-mine (ROM) and washed coals were used as feedstocks to determine the effects of levels of mineral matter, specifically iron compounds. Liquefaction reactivity as characterized by total distillate yield was lower for washed coal, which contained less mineral matter. Liquefaction reactivity was regained when pyrite concentrate was added as a disposable catalyst to the washed coal feed in sufficient quantity to match the feed iron concentration of the run-of-mine coal liquefaction test run.

  7. 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.

  8. 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.

  9. 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.

  10. 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...

  11. 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 measuremen...

  12. The gas-liquid mass transfer coefficient (k(L)a) in the gas-liquid Multi-stage Agitated Contactor (MAC)

    NARCIS (Netherlands)

    Breman, B.B; Beenackers, A.A C M; Bouma, M.J; VanderWerf, M.H.

    1996-01-01

    Data on the volumetric liquid-side gas-liquid mass transfer coefficient, k(L)a, in a Multi-stage Agitated Contractor (MAC) are reported for three gas-liquid systems (air-water, helium-n-octane, and air-Monoethylene Glycol (MEG)). k(L)a (s(-1)) was determined using a dynamic method with moderately so

  13. A Multi-Stage Longitudinal Comparative Design Stage II Evaluation of the Changing Lives Program: The Life Course Interview (RDA-LCI)

    Science.gov (United States)

    Arango, Lisa Lewis; Kurtines, William M.; Montgomery, Marilyn J.; Ritchie, Rachel

    2008-01-01

    The study reported in this article, a Multi-Stage Longitudinal Comparative Design Stage II evaluation conducted as a planned preliminary efficacy evaluation (psychometric evaluation of measures, short-term controlled outcome studies, etc.) of the Changing Lives Program (CLP), provided evidence for the reliability and validity of the qualitative…

  14. Economic and thermal feasibility of multi stage flash desalination plant with brine–feed mixing and cooling

    International Nuclear Information System (INIS)

    Improving the performance of MSF (multi stage flash) desalination plants is a major challenge for desalination industry. High feed temperature in summer shortens the evaporation range of MSF plants and limits their yield. Installing a cooler at the feed intake expands the evaporation range of MSF plants and increases their yield. Adding a cooler and a mixing chamber increases the capital and operational costs of MSF plants. This paper presents thermal and economic analysis of installing a feed cooler at the plant intake. The profit of selling the additionally produced water must cover the cost of the cooling system. The selling prices for a reasonable breakeven depend on the selected cooling temperature. The cost of installing coolers capable of maintaining feed–brine mixture temperatures of 18–20 °C shows breakeven selling prices of 0.5–0.9 $/m3. These prices fall within the current range of potable water selling prices. - Highlights: • Thermo-economic analysis for MSF plant with brine mixing and cooling is presented. • Analysis is based on first and second laws of thermodynamics. • The profit gained from producing additional water covers the cooling cost. • The suggested modification is a promising technique for plants in hot climates

  15. Multi-stage ranking of emergency technology alternatives for water source pollution accidents using a fuzzy group decision making tool.

    Science.gov (United States)

    Qu, Jianhua; Meng, Xianlin; You, Hong

    2016-06-01

    Due to the increasing number of unexpected water source pollution events, selection of the most appropriate disposal technology for a specific pollution scenario is of crucial importance to the security of urban water supplies. However, the formulation of the optimum option is considerably difficult owing to the substantial uncertainty of such accidents. In this research, a multi-stage technical screening and evaluation tool is proposed to determine the optimal technique scheme, considering the areas of pollutant elimination both in drinking water sources and water treatment plants. In stage 1, a CBR-based group decision tool was developed to screen available technologies for different scenarios. Then, the threat degree caused by the pollution was estimated in stage 2 using a threat evaluation system and was partitioned into four levels. For each threat level, a corresponding set of technique evaluation criteria weights was obtained using Group-G1. To identify the optimization alternatives corresponding to the different threat levels, an extension of TOPSIS, a multi-criteria interval-valued trapezoidal fuzzy decision making technique containing the four arrays of criteria weights, to a group decision environment was investigated in stage 3. The effectiveness of the developed tool was elaborated by two actual thallium-contaminated scenarios associated with different threat levels. PMID:26897576

  16. A Risk-Constrained Multi-Stage Decision Making Approach to the Architectural Analysis of Mars Missions

    Science.gov (United States)

    Kuwata, Yoshiaki; Pavone, Marco; Balaram, J. (Bob)

    2012-01-01

    This paper presents a novel risk-constrained multi-stage decision making approach to the architectural analysis of planetary rover missions. In particular, focusing on a 2018 Mars rover concept, which was considered as part of a potential Mars Sample Return campaign, we model the entry, descent, and landing (EDL) phase and the rover traverse phase as four sequential decision-making stages. The problem is to find a sequence of divert and driving maneuvers so that the rover drive is minimized and the probability of a mission failure (e.g., due to a failed landing) is below a user specified bound. By solving this problem for several different values of the model parameters (e.g., divert authority), this approach enables rigorous, accurate and systematic trade-offs for the EDL system vs. the mobility system, and, more in general, cross-domain trade-offs for the different phases of a space mission. The overall optimization problem can be seen as a chance-constrained dynamic programming problem, with the additional complexity that 1) in some stages the disturbances do not have any probabilistic characterization, and 2) the state space is extremely large (i.e, hundreds of millions of states for trade-offs with high-resolution Martian maps). To this purpose, we solve the problem by performing an unconventional combination of average and minimax cost analysis and by leveraging high efficient computation tools from the image processing community. Preliminary trade-off results are presented.

  17. Multi-stage Modeling of Lüders Elongation and Work-Hardening Behaviors of Ferrite Steels Under Tension

    Science.gov (United States)

    Zhang, Zhongyang; Liao, Yiliang

    2016-04-01

    For structural and engineering steels, accurate modeling of stress-strain relation of ferrite phase is of particular importance, since the modeling results could benefit new material system design and process-microstructure-property analysis. Several modeling efforts have been made to achieve this target. However, few efforts have been put on the Lüders elongation behavior of ferrite. As a result, the modeling results from proposed models do not match well with experimental data, particularly at a relatively low-strain range. Furthermore, without the consideration of yield point elongation due to the formation of Lüders bands, additional calibration parameters are required to capture the stress level of stress-strain curves. In this work, a multi-stage model is developed to predict the stress-strain relation of ferrite phase steel under room temperature tension. This model is capable of capturing the grain size effect on both Lüders elongation and work-hardening behaviors of ferrite. The modeling results are extensively validated by experimental data.

  18. Seven novel prostate cancer susceptibility loci identified by a multi-stage genome-wide association study

    Science.gov (United States)

    Kote-Jarai, Zsofia; Olama, Ali Amin Al; Giles, Graham G.; Severi, Gianluca; Schleutker, Johanna; Weischer, Maren; Canzian, Frederico; Riboli, Elio; Key, Tim; Gronberg, Henrik; Hunter, David J.; Kraft, Peter; Thun, Michael J; Ingles, Sue; Chanock, Stephen; Albanes, Demetrius; Hayes, Richard B; Neal, David E.; Hamdy, Freddie C.; Donovan, Jenny L.; Pharoah, Paul; Schumacher, Fredrick; Henderson, Brian E.; Stanford, Janet L.; Ostrander, Elaine A.; Sorensen, Karina Dalsgaard; Dörk, Thilo; Andriole, Gerald; Dickinson, Joanne L.; Cybulski, Cezary; Lubinski, Jan; Spurdle, Amanda; Clements, Judith A.; Chambers, Suzanne; Aitken, Joanne; Frank Gardiner, R. A.; Thibodeau, Stephen N.; Schaid, Dan; John, Esther M.; Maier, Christiane; Vogel, Walther; Cooney, Kathleen A.; Park, Jong Y.; Cannon-Albright, Lisa; Brenner, Hermann; Habuchi, Tomonori; Zhang, Hong-Wei; Lu, Yong-Jie; Kaneva, Radka; Muir, Ken; Benlloch, Sara; Leongamornlert, Daniel A.; Saunders, Edward J.; Tymrakiewicz, Malgorzata; Mahmud, Nadiya; Guy, Michelle; O’Brien, Lynne T.; Wilkinson, Rosemary A.; Hall, Amanda L.; Sawyer, Emma J.; Dadaev, Tokhir; Morrison, Jonathan; Dearnaley, David P.; Horwich, Alan; Huddart, Robert A.; Khoo, Vincent S.; Parker, Christopher C.; Van As, Nicholas; Woodhouse, Christopher J.; Thompson, Alan; Christmas, Tim; Ogden, Chris; Cooper, Colin S.; Lophatonanon, Aritaya; Southey, Melissa C.; Hopper, John L.; English, Dallas; Wahlfors, Tiina; Tammela, Teuvo LJ; Klarskov, Peter; Nordestgaard, Børge G.; Røder, M. Andreas; Tybjærg-Hansen, Anne; Bojesen, Stig E.; Travis, Ruth; Campa, Daniele; Kaaks, Rudolf; Wiklund, Fredrik; Aly, Markus; Lindstrom, Sara; Diver, W Ryan; Gapstur, Susan; Stern, Mariana C; Corral, Roman; Virtamo, Jarmo; Cox, Angela; Haiman, Christopher A.; Le Marchand, Loic; FitzGerald, Liesel; Kolb, Suzanne; Kwon, Erika M.; Karyadi, Danielle M.; Orntoft, Torben Falck; Borre, Michael; Meyer, Andreas; Serth, Jürgen; Yeager, Meredith; Berndt, Sonja I.; Marthick, James R; Patterson, Briony; Wokolorczyk, Dominika; Batra, Jyotsna; Lose, Felicity; McDonnell, Shannon K; Joshi, Amit D.; Shahabi, Ahva; Rinckleb, Antje E.; Ray, Ana; Sellers, Thomas A.; Lin, Huo-Yi; Stephenson, Robert A; Farnham, James; Muller, Heiko; Rothenbacher, Dietrich; Tsuchiya, Norihiko; Narita, Shintaro; Cao, Guang-Wen; Slavov, Chavdar; Mitev, Vanio; Easton, Douglas F.; Eeles, Rosalind A.

    2012-01-01

    Prostate cancer (PrCa) is the most frequently diagnosed male cancer in developed countries. To identify common PrCa susceptibility alleles, we conducted a multi-stage genome-wide association study and previously reported the results of the first two stages, which identified 16 novel susceptibility loci for PrCa. Here we report the results of stage 3 in which we evaluated 1,536 SNPs in 4,574 cases and 4,164 controls. Ten novel association signals were followed up through genotyping in 51,311 samples in 30 studies through the international PRACTICAL consortium. In addition to previously reported loci, we identified a further seven new prostate cancer susceptibility loci on chromosomes 2p, 3q, 5p, 6p, 12q and Xq (P=4.0 ×10−8 to P=2.7 ×10−24). We also identified a SNP in TERT more strongly associated with PrCa than that previously reported. More than 40 PrCa susceptibility loci, explaining ~25% of the familial risk in this disease, have now been identified. PMID:21743467

  19. Multi-stage ranking of emergency technology alternatives for water source pollution accidents using a fuzzy group decision making tool.

    Science.gov (United States)

    Qu, Jianhua; Meng, Xianlin; You, Hong

    2016-06-01

    Due to the increasing number of unexpected water source pollution events, selection of the most appropriate disposal technology for a specific pollution scenario is of crucial importance to the security of urban water supplies. However, the formulation of the optimum option is considerably difficult owing to the substantial uncertainty of such accidents. In this research, a multi-stage technical screening and evaluation tool is proposed to determine the optimal technique scheme, considering the areas of pollutant elimination both in drinking water sources and water treatment plants. In stage 1, a CBR-based group decision tool was developed to screen available technologies for different scenarios. Then, the threat degree caused by the pollution was estimated in stage 2 using a threat evaluation system and was partitioned into four levels. For each threat level, a corresponding set of technique evaluation criteria weights was obtained using Group-G1. To identify the optimization alternatives corresponding to the different threat levels, an extension of TOPSIS, a multi-criteria interval-valued trapezoidal fuzzy decision making technique containing the four arrays of criteria weights, to a group decision environment was investigated in stage 3. The effectiveness of the developed tool was elaborated by two actual thallium-contaminated scenarios associated with different threat levels.

  20. Utilization of desulfurization gypsum to producing SO{sub 2} and CaO in multi-stage fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Zhu; Wang, Tao; Yang, Hairui; Zhang, Hai; Zhang, Zuyi [Tsinghua Univ., Beijing (China). Dept. of Thermal Engineering; Ministry of Education, Beijing (China). Key Lab. for Thermal Science and Power Engineering

    2013-07-01

    With emission control becomes more and more stringent, flue gas desulphurization (FGD) is commonly employed for desulfurization. However, the product of FGD, gypsum, causes the unexpected environmental problems. How to utilize the byproduct of FGD effectively and economically is a challenging task. This paper proposed the new technical process to produce SO{sub 2} and CaO by reducing the gypsum in multi-stage fluidized bed reactor with different atmosphere. In addition, some preliminary experiments were carried out in PTGA. The results show that CO concentration has little effect on the initial decomposing temperature, but affect the decomposing rate of phosphogypsum obviously. The decomposing product composed of CaS and CaO simultaneously. The ratio of the two products was determined by CO concentration. Lower CO content benefits to produce more CO product and more SO{sub 2}. The decomposition reaction of phosphogypsum in reducing atmosphere is parallel competition reaction. Therefore, it is necessary to eliminate the effect of CaS and other byproduct efficiently by the new technology, which utilize multi-atmosphere in multistage fluidized bed reactors.

  1. Multi-Stage Feature Selection by Using Genetic Algorithms for Fault Diagnosis in Gearboxes Based on Vibration Signal

    Directory of Open Access Journals (Sweden)

    Mariela Cerrada

    2015-09-01

    Full Text Available There are growing demands for condition-based monitoring of gearboxes, and techniques to improve the reliability, effectiveness and accuracy for fault diagnosis are considered valuable contributions. Feature selection is still an important aspect in machine learning-based diagnosis in order to reach good performance in the diagnosis system. The main aim of this research is to propose a multi-stage feature selection mechanism for selecting the best set of condition parameters on the time, frequency and time-frequency domains, which are extracted from vibration signals for fault diagnosis purposes in gearboxes. The selection is based on genetic algorithms, proposing in each stage a new subset of the best features regarding the classifier performance in a supervised environment. The selected features are augmented at each stage and used as input for a neural network classifier in the next step, while a new subset of feature candidates is treated by the selection process. As a result, the inherent exploration and exploitation of the genetic algorithms for finding the best solutions of the selection problem are locally focused. The Sensors 2015, 15 23904 approach is tested on a dataset from a real test bed with several fault classes under different running conditions of load and velocity. The model performance for diagnosis is over 98%.

  2. STUDY OF SOLVENT AND CATALYST INTERACTIONS IN DIRECT COAL LIQUEFACTION

    Energy Technology Data Exchange (ETDEWEB)

    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

  3. Iodine-catalyzed coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, J.T.; Duffield, J.E.; Davidson, M.G. (Amoco Oil Company, Naperville, IL (USA). Research and Development Dept.)

    Coals of two different ranks were liquefied in high yields using catalytic quantities of elemental iodine or iodine compounds. Iodine monochloride was found to be especially effective for enhancing both coal conversion and product quality. It appears that enhancement in coal conversion is due to the unique ability of iodine to catalyze radical-induced bond scission and hydrogen addition to the coal macromolecule or coal-derived free radicals. The starting iodine can be fully accounted for in the reaction products as both organic-bound and water-soluble forms. Unconverted coal and the heavy product fractions contain the majority of the organic-bound iodine. The results of iodine-catalyzed coal reactions emphasize the need for efficient hydrogen atom transfer along with bond scission to achieve high conversion and product quality. 22 refs., 12 tabs.

  4. LIQUEFACTION AND DISPLACEMENT OF SATURATED SAND UNDER VERTICAL VIBRATION LOADING

    Institute of Scientific and Technical Information of China (English)

    LU Xiaobing; TAN Qingming; CHENG C.M.; YU Shanbing; CUI Peng

    2004-01-01

    In order to investigate the influence of the vertical vibration loading on the liquefaction of saturated sand, one dimensional model for the saturated sand with a vertical vibration is presented based on the two phase continuous media theory. The development of the liquefaction and the liquefaction region are analyzed. It is shown that the vertical vibration loading could induce liquefaction.The rate of the liquefaction increases with the increase of the initial limit strain or initial porosity or amplitude and frequency of loading, and increases with the decrease of the permeability or initial modulus. It is shown also that there is a phase lag in the sand column. When the sand permeability distribution is non-uniform, the pore pressure and the strain will rise sharply where the permeability is the smallest, and fracture might be induced. With the development of liquefaction, the strength of the soil foundation becomes smaller and smaller. In the limiting case, landslides or debris flows could occur.

  5. 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.

    1991-09-01

    The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of the catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experimental program will focus upon the development of effective methods of impregnating coal with catalysts, evaluating the conditions under which the catalysts are most active and establishing the relative impact of improved impregnation on conversion and product distributions obtained from coal hydrogenation. Liquefaction experiments of solvent-treated and untreated Blind Canyon (DECS-6) and Texas lignite (DECS-1) have been performed using ammonium tetrathiomolybdate (ATTM) and bis (dicarbonylcyclopentadienyl) iron (CPI) as catalyst precursors using temperature-staged conditions (275{degrees}C, 30 min; 425{degrees}C, 30 min). Solid state {sup 13}C NMR analysis was carried out for each coal and for selected residues. 12 refs., 14 figs., 9 tabs.

  6. Multi-Stage 20-m Shuttle Run Fitness Test, Maximal Oxygen Uptake and Velocity at Maximal Oxygen Uptake

    Directory of Open Access Journals (Sweden)

    Paradisis Giorgos P.

    2014-07-01

    Full Text Available The multi-stage 20-m shuttle run fitness test (20mMSFT is a popular field test which is widely used to measure aerobic fitness by predicting maximum oxygen uptake (VO2 max and performance. However, the velocity at which VO 2 max occurs (vVO 2 max is a better indicator of performance than VO 2 max, and can be used to explain inter-individual differences in performance that VO 2 max cannot. It has been reported as a better predictor for running performance and it can be used to monitor athletes’ training for predicting optimal training intensity. This study investigated the validity and suitability of predicting VO2max and vVO2max of adult subjects on the basis of the performance of the 20mMST. Forty eight (25 male and 23 female physical education students performed, in random order, a laboratory based continuous horizontal treadmill test to determine VO2max, vVO 2 max and a 20mMST, with an interval of 3 days between each test. The results revealed significant correlations between the number of shuttles in the 20mMSFT and directly determined VO 2 max (r = 0.87, p<0.05 and vVO 2 max (r = 0.93, p<0.05. The equation for prediction of VO 2 max was y = 0.0276x + 27.504, whereas for vVO 2 max it was y = 0.0937x + 6.890. It can be concluded that the 20mMSFT can accurately predict VO 2 max and vVO 2 max and this field test can provide useful information regarding aerobic fitness of adults. The predicted vVO 2 max can be used in monitoring athletes, especially in determining optimal training intensity.

  7. Experimental Results of the First Two Stages of an Advanced Transonic Core Compressor Under Isolated and Multi-Stage Conditions

    Science.gov (United States)

    Prahst, Patricia S.; Kulkarni, Sameer; Sohn, Ki H.

    2015-01-01

    NASA's Environmentally Responsible Aviation (ERA) Program calls for investigation of the technology barriers associated with improved fuel efficiency of large gas turbine engines. Under ERA the task for a High Pressure Ratio Core Technology program calls for a higher overall pressure ratio of 60 to 70. This mean that the HPC would have to almost double in pressure ratio and keep its high level of efficiency. The challenge is how to match the corrected mass flow rate of the front two supersonic high reaction and high corrected tip speed stages with a total pressure ratio of 3.5. NASA and GE teamed to address this challenge by using the initial geometry of an advanced GE compressor design to meet the requirements of the first 2 stages of the very high pressure ratio core compressor. The rig was configured to run as a 2 stage machine, with Strut and IGV, Rotor 1 and Stator 1 run as independent tests which were then followed by adding the second stage. The goal is to fully understand the stage performances under isolated and multi-stage conditions and fully understand any differences and provide a detailed aerodynamic data set for CFD validation. Full use was made of steady and unsteady measurement methods to isolate fluid dynamics loss source mechanisms due to interaction and endwalls. The paper will present the description of the compressor test article, its predicted performance and operability, and the experimental results for both the single stage and two stage configurations. We focus the detailed measurements on 97 and 100 of design speed at 3 vane setting angles.

  8. Exprimental Results of the First Two Stages of an Advanced Transonic Core Compressor Under Isolated and Multi-Stage Conditions.

    Science.gov (United States)

    Prahst, Patricia S.; Kulkarni, Sameer; Sohn, Ki H.

    2015-01-01

    NASA's Environmentally Responsible Aviation (ERA) Program calls for investigation of the technology barriers associated with improved fuel efficiency for large gas turbine engines. Under ERA, the highly loaded core compressor technology program attempts to realize the fuel burn reduction goal by increasing overall pressure ratio of the compressor to increase thermal efficiency of the engine. Study engines with overall pressure ratio of 60 to 70 are now being investigated. This means that the high pressure compressor would have to almost double in pressure ratio while keeping a high level of efficiency. NASA and GE teamed to address this challenge by testing the first two stages of an advanced GE compressor designed to meet the requirements of a very high pressure ratio core compressor. Previous test experience of a compressor which included these front two stages indicated a performance deficit relative to design intent. Therefore, the current rig was designed to run in 1-stage and 2-stage configurations in two separate tests to assess whether the bow shock of the second rotor interacting with the upstream stage contributed to the unpredicted performance deficit, or if the culprit was due to interaction of rotor 1 and stator 1. Thus, the goal was to fully understand the stage 1 performance under isolated and multi-stage conditions, and additionally to provide a detailed aerodynamic data set for CFD validation. Full use was made of steady and unsteady measurement methods to understand fluid dynamics loss source mechanisms due to rotor shock interaction and endwall losses. This paper will present the description of the compressor test article and its measured performance and operability, for both the single stage and two stage configurations. We focus the paper on measurements at 97% corrected speed with design intent vane setting angles.

  9. Earthquake Risk - MO 2013 Liquefaction Potential St. Louis Area (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Soil liquefaction potential was determined using existing surficial materials and floodplain alluvium maps. Alluvium deposits and artificial deposits are generally...

  10. 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.

  11. Ultrasound-assisted liquefaction of honey

    OpenAIRE

    Kabbani, Dania

    2014-01-01

    Crystallization of honey is a common process of the honey industry. Liquid honey is preferred by most of the consumers and by food companies for ease of handling. Honey is commonly heated during pasteurization in order to liquefy it and inhibit any microbial growth. However, heating can degrade the main quality parameters of honey. A better method compared to expensive and time-consuming heating is desirable to pasteurize, accelerate the liquefaction and retard the crystallization process...

  12. Coal liquefaction process streams characterization and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, J.A.; Linehan, J.C.; Robins, W.H. (Battelle Pacific Northwest Lab., Richland, WA (United States))

    1992-07-01

    Under contract from the DOE , and in association with CONSOL Inc., Battelle, Pacific Northwest Laboratory (PNL) evaluated four principal and several complementary techniques for the analysis of non-distillable direct coal liquefaction materials in support of process development. Field desorption mass spectrometry (FDMS) and nuclear magnetic resonance (NMR) spectroscopic methods were examined for potential usefulness as techniques to elucidate the chemical structure of residual (nondistillable) direct coal liquefaction derived materials. Supercritical fluid extraction (SFE) and supercritical fluid chromatography/mass spectrometry (SFC/MS) were evaluated for effectiveness in compound-class separation and identification of residual materials. Liquid chromatography (including microcolumn) separation techniques, gas chromatography/mass spectrometry (GC/MS), mass spectrometry/mass spectrometry (MS/MS), and GC/Fourier transform infrared (FTIR) spectroscopy methods were applied to supercritical fluid extracts. The full report authored by the PNL researchers is presented here. The following assessment briefly highlights the major findings of the project, and evaluates the potential of the methods for application to coal liquefaction materials. These results will be incorporated by CONSOL into a general overview of the application of novel analytical techniques to coal-derived materials at the conclusion of CONSOL's contract.

  13. Thermal modelling of the multi-stage heating system with variable boundary conditions in the wafer based precision glass moulding process

    DEFF Research Database (Denmark)

    Sarhadi, Ali; Hattel, Jesper Henri; Hansen, Hans Nørgaard;

    2012-01-01

    of the heating system in the glass moulding process considering detailed heating mechanisms therefore plays an important part in optimizing the heating system and the subsequent pressing stage in the lens manufacturing process.The current paper deals with three-dimensional transient thermal modelling...... of the multi-stage heating system in a wafer based glass moulding process. In order to investigate the importance of the radiation from the interior and surface of the glass, a simple finite volume code is developed to model one dimensional radiation–conduction heat transfer in the glass wafer for an extreme...... pressures. Finally, the three-dimensional modelling of the multi-stage heating system in the wafer based glass moulding process is simulated with the FEM software ABAQUS for a particular industrial application for mobile phone camera lenses to obtain the temperature distribution in the glass wafer...

  14. Power supply to the air-core transformer coils of a large tokamak by a multi-stage inductive energy storage system

    International Nuclear Information System (INIS)

    The multi-stage inductive energy storage circuits have been studied by a simplex method to obtain an optimum design of a power supply system for the air-core transformer coils of a large tokamak. Parameters of the electric circuits subject to various constraints were determined by the method. The multi-stage inductive energy storage system is better than the single-stage system in viewpoint of the energy necessary to build up the plasma current. Circuit analysis including the plasma was made for the two cases: (1) the plasma resistance given as a function of time, and (2) the plasma resistance determined from a zero-dimensional plasma model. The plasma self-inductance and its time variation play an important role during the build up of plasma current, and influence largely on the optimal circuit parameters. (auth.)

  15. Multi-stage open peer review: scientific evaluation integrating the strengths of traditional peer review with the virtues of transparency and self-regulation

    Directory of Open Access Journals (Sweden)

    Ulrich ePöschl

    2012-07-01

    Full Text Available The traditional forms of scientific publishing and peer review do not live up to the demands of efficient communication and quality assurance in today’s highly diverse and rapidly evolving world of science. They need to be advanced and complemented by interactive and transparent forms of review, publication, and discussion that are open to the scientific community and to the public.The advantages of open access, public peer review and interactive discussion can be efficiently and flexibly combined with the strengths of traditional scientific peer review. Since 2001 the benefits and viability of this approach are clearly demonstrated by the highly successful interactive open access journal Atmo¬sphe¬ric Chemistry and Physics (ACP and a growing number of sister journals launched and operated by the European Geosciences Union (EGU and the open access publisher Copernicus.The interactive open access journals are practicing an integrative multi-stage process of publication and peer review combined with interactive public discussion, which effectively resolves the dilemma between rapid scientific exchange and thorough quality assurance. The high efficiency and predictive validity of multi-stage open peer review have been confirmed in a series of dedicated studies by evaluation experts from the social sciences, and the same or similar concepts have recently also been adopted in other disciplines, including the life sciences and economics. Multi-stage open peer review can be flexibly adjusted to the needs and peculiarities of different scientific communities. Due to the flexibility and compatibility with traditional structures of scientific publishing and peer review, the multi-stage open peer review concept enables efficient evolution in scientific communication and quality assurance. It has the potential for swift replacement of hidden peer review as the standard of scientific quality assurance, and it provides a basis for open evaluation in

  16. Comparing a single-stage geocoding method to a multi-stage geocoding method: how much and where do they disagree?

    Directory of Open Access Journals (Sweden)

    Rice Kenneth

    2007-03-01

    Full Text Available Abstract Background Geocoding methods vary among spatial epidemiology studies. Errors in the geocoding process and differential match rates may reduce study validity. We compared two geocoding methods using 8,157 Washington State addresses. The multi-stage geocoding method implemented by the state health department used a sequence of local and national reference files. The single-stage method used a single national reference file. For each address geocoded by both methods, we measured the distance between the locations assigned by each method. Area-level characteristics were collected from census data, and modeled as predictors of the discordance between geocoded address coordinates. Results The multi-stage method had a higher match rate than the single-stage method: 99% versus 95%. Of 7,686 addresses were geocoded by both methods, 96% were geocoded to the same census tract by both methods and 98% were geocoded to locations within 1 km of each other by the two methods. The distance between geocoded coordinates for the same address was higher in sparsely populated and low poverty areas, and counties with local reference files. Conclusion The multi-stage geocoding method had a higher match rate than the single-stage method. An examination of differences in the location assigned to the same address suggested that study results may be most sensitive to the choice of geocoding method in sparsely populated or low-poverty areas.

  17. Simulation of a multi-stage adiabatic reactor with inter-stage quenching for dimethyl ether synthesis

    Directory of Open Access Journals (Sweden)

    Bai Ziyang

    2014-01-01

    Full Text Available Adiabatic fixed-bed reactor has proven commercially successful in large scale production of catalytic dehydration of methanol to dimethyl ether. A one dimensional pseudo-homogeneous model of an industrial reactor of dimethyl ether synthesis has been established. To verify the proposed model, the simulation results have been compared to available data from an industrial reactor. A good agreement has been found between them. The distribution of the catalyst bed temperature and concentration of each component was obtained under conditions of inlet temperature 260°C, reaction pressure 1.2MPa and gaseous hourly space velocity 950.7 h-1. With inlet catalyst bed temperature 240-280°C, operating pressure 0.6-1.8MPa and gaseous hourly space velocity 831.8-1069.5 h-1, the influence of these reaction conditions on temperature distribution of the reactor catalytic bed, outlet methanol conversion and the dimethyl ether yield were calculated. The results show that, with the rise of inlet temperature (240-280°C and operating pressure (0.6-1.8MPa, the outlet conversion of methanol, the hot spot temperature and the DME yield increased. The increase of gaseous hourly space velocity (831.8-1069.5 h-1 leads to a decrease in the hot spot temperature of catalytic bed and the outlet conversion of methanol. But the DME yield rise initially and then descend.

  18. Triassic to Cenozoic multi-stage intra-plate deformation focused near the Bogd Fault system, Gobi Altai, Mongolia

    Institute of Scientific and Technical Information of China (English)

    Douwe J.J. van Hinsbergen; Dickson Cunningham; Gijsbert B. Straathof; Morgan Ganerød; Bart W.H. Hendriks; Arjan H. Dijkstra

    2015-01-01

    The Gobi Altai region of southern Mongolia has been in the Eurasian plate interior since the mid-Mesozoic, yet has experienced episodic phases of deformation since that time. In this paper, we docu-ment field evidence to characterize and date the intra-plate tectonic history of the Gobi Altai region from the Triassic to the present. To this end, we provide detailed mapping of the structure and stratigraphy of the eastern flanks of Mt. Ih Bogd that contains the widest variety of rock-time units in the area. We carry out geochronological analysis of basaltic lavas and basement granite in the area. We demonstrate that a crystalline basement with a 502 ? 8 Ma granitoid (U/Pb) underwent two phases of basin formation in the Mesozoic, which we date with new 40Ar/39Ar lava ages of 218.5 ? 1.5, 123.2 ? 0.7 and 124.8 ? 1.2 Ma, respectively. Both phases are linked to deposition of fluvio-lacustrine sediments and trap-like basaltic volcanics, with cumulative thicknesses of 1000e1500 m. Both basins were likely north-facing half-gra-bens that developed under wNeS extension, but were subsequently overthrusted by Paleozoic and older crystalline basement during a less well constrained, but likely mid-Cretaceous phase of NeS shortening and basin inversion. Our results are consistent with recent seismic imaging of rift basins w100 km to the NE of the study area where a similar history was reconstructed. The multiple phases of intra-plate deformation appear to have parallel structural trends, most likely due to reactivated Paleozoic base-ment structures created during the original terrane amalgamation of the Central Asian Orogenic Belt continental crust. This strong basement heterogeneity may predispose it to reactivation, and make it sensitive to changes in the overall stress field of the Eurasian plate driven by forces at its margins and base. Detailed study of Mongolia’s multi-stage tectonic history may thus provide a key proxy for the long-term dynamics of the Eurasian plate. In

  19. Liquefaction hazard analysis for infrastructure development in gulf of Jakarta

    Science.gov (United States)

    Dinata, Indra A.; Darlan, Yudi; Sadisun, Imam A.; Pindratno, Haris; Saryanto, Agus

    2016-05-01

    Gulf of Jakarta is an area of active sedimentation. There exist a wide sediment deposition area on the north coast of Jakarta. Generally, these sediments have not been consolidated, so that the conditions in these area is an important factor to determining liquefaction in these area. Liquefaction may occur because of earthquake that cause loss of strength and stiffness in soils. Analysis of liquefaction potential based from SPT data taken at gulf of Jakarta, include susceptibility rate and the factors that triggering. Liquefaction analysis methods compared with each other to get the factor of safety against liquefaction according to the characteristics of the soil. Liquefaction analysis at surface using susceptibility rating factor (SRF). SRF method controled by factors: history, geology, composition, and groundwater. Each factors have parameters that determine the value of SRF.From the analysis, Gulf of Jakarta has susceptibility rating from liquefaction with SRF value 12 - 35. The value shows that Gulf of Jakarta dominated by area that have susceptibility rating from medium to high. High susceptibility rating from liquefaction concentrated at coast area.

  20. An optimal design methodology for large-scale gas liquefaction

    International Nuclear Information System (INIS)

    Highlights: ► Configuration selection and parametric optimization carried out simultaneously for gas liquefaction systems. ► Effective Heat Transfer Factor proposed to indicate the performance of heat exchanger networks. ► Relatively high exergy efficiency of liquefaction process achievable under some general assumptions. -- Abstract: This paper presents an optimization methodology for thermodynamic design of large scale gas liquefaction systems. Such a methodology enables configuration selection and parametric optimization to be implemented simultaneously. Exergy efficiency and genetic algorithm have been chosen as an evaluation index and an evaluation criterion, respectively. The methodology has been applied to the design of expander cycle based liquefaction processes. Liquefaction processes of hydrogen, methane and nitrogen are selected as case studies and the simulation results show that relatively high exergy efficiencies (52% for hydrogen and 58% for methane and nitrogen) are achievable based on very general consumptions.

  1. 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...... 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......, a zone of the corridor of Tabriz urban railway line 2 susceptible to liquefaction was recognized. Then, using numerical analysis and cyclic stress method using QUAKE/W finite element code, soil liquefaction potential in susceptible zone was evaluated based on design earthquake....

  2. 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.

  3. 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.

  4. Pyrolysis characteristics and kinetics of residue from China Shenhua industrial direct coal liquefaction plant

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Pyrolysis behavior of direct coal liquefaction residue (DCLR) and its four fractions were investigated. • The inorganic components in DCLR have catalytic effects on both pyrolysis and gasification. • The pyrolysis activation energy of DCLR obtained from DAEM is in the range of 68.4–142.9 kJ/mol. - Abstract: The objective of this work is to comprehensively investigate the pyrolysis characteristics of the direct coal liquefaction residue (DCLR) from China Shenhua industrial direct coal liquefaction plant. The pyrolysis experiments were conducted with TGA under four kinds of atmospheres (N2, 10% H2, CO2, and air) and a fixed bed reactor in N2. Two obvious mass loss peaks at 470 °C and 770 °C, are mainly attributed to decomposition of the organic matrix and inorganic compounds in DCLR, respectively. The four fractions extracted from DCLR (hexane soluble fraction (HS), asphaltene fraction (A), preasphaltene (PA), and tetrahydrofuran insoluble (THFIS)) were studied separately by TG-FTIR, and the results show that the interaction among the fractions is unfavorable for the evolution of volatile matter. In addition, the inorganic compounds in DCLR exhibit catalysis behaviors on both pyrolysis under N2 and gasification under CO2. Moreover, the properties of DCLR pyrolysis products obtained from the fixed bed reactor were analyzed by GC–MS, SEM, and FTIR. Finally, a kinetic analysis of DCLR pyrolysis was performed using the distributed activation energy model (DAEM). The activation energy distribution of DCLR follows an approximate Gaussian distribution with a mean activation energy of 87.6 kJ/mol

  5. 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.

  6. Gastrointestinal stromal tumor: acute liquefaction necrosis

    International Nuclear Information System (INIS)

    Stromal tumors, together with leiomyomas and schwannomas, constitute the sol-called mesenchymal tumors of the intestinal wall. Stromal tumors are histologically differentiated from other mesenchymal tumors in that they are derived from the interstitial cell of Cajal. These tumors can be encountered at any point throughout the entire digestive tract, by usually develop in stomach or small bowel. the clinical presentation in anemia secondary to gastrointestinal bleeding. Acute abdomen due to perforation or necrosis is rare. We present a case of jejunal stromal tumors with massive liquefaction necrosis, a circumstance that resulted in the peculiar radiological features observed. (Author) 9 refs,

  7. Piezometer Performance at Wildlife Liquefaction Site, California

    OpenAIRE

    Scott, Ronald F.; Hushmand, B.

    1995-01-01

    In response to an urgent need for field data from instrumented liquefaction sites, the U.S. Geological Survey in 1982 selected and instrumented a site in southern California called the Wildlife site. Two accelerometers (one at ground surface and one at a depth of 7.5 m) and six electrical pore-pressure transducers (five in a liquefiable silty sand layer) were placed at the site. The November 1987 Superstition Hills earthquake triggered sand boils and the desired instrumental response by gener...

  8. Titanite-scale insights into multi-stage magma mixing in Early Cretaceous of NW Jiaodong terrane, North China Craton

    Science.gov (United States)

    Jiang, Peng; Yang, Kui-Feng; Fan, Hong-Rui; Liu, Xuan; Cai, Ya-Chun; Yang, Yue-Heng

    2016-08-01

    REEs contents, and Th/U ratios, but reveal high F contents (0.35-0.76 wt.%) and extreme high Nb/Ta ratios (up to 65.6). Such titanites are perceived to record late-stage mingling, during which F-rich and REE-poor hybrid granodioritic magma squeezed into the incompletely consolidated dioritic enclaves with accompanying fluid-rock interaction. Combining our results with previous isotopic studies, a new genetic model for Guojialing-type granodiorites is envisaged, which involves multi-stage magma mixing between Archean lower crust-derived felsic magma and mafic lower crust-derived dioritic magma, triggered by mantle-derived mafic magma underplating during the course of asthenospheric upwelling in Early Cretaceous. Such process further implicates the reactivation of Jiaodong lower crust during the destruction of NCC.

  9. Chemical analysis and mutational assay of distilled oils from the H-coal direct liquefaction process: a status report

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, B.W.; Later, D.W.; Wright, C.W.; Stewart, D.L.

    1985-01-01

    Samples from the H-Coal process, a catalytic, single-stage, coal liquefaction technology, were chemically characterized and screened for microbial mutagenicity. For these investigations, a blend of light and heavy H-Coal process oils was fractionally distilled into 50/sup 0/F boiling point cuts. The chemical analyses and biological testing results presented in this status report deal primarily with the blended material and the distillate fractions boiling above 650/sup 0/F. Results from the microbial mutagenicity assays indicated that onset of biological activity in the crude materials occurred above 700/sup 0/F. Similar trends have been observed for Solvent Refined Coal (SRC) I, SRC II, Integrated Two-Stage Liquefaction (ITSL) and Exxon EDS process materials. After chemical class fractionation, the primary source of microbial mutagenicity of the crude boiling point cuts was the nitrogen-containing polycyclic aromatic compound (N-PAC) fractions. Amino polycyclic aromatic hydrocarbons (amino-PAH) were present at sufficient concentration levels in the N-PAC fractions to account for the observed mutagenic responses. In general, the chemical composition of the H-Coal materials studied was similar to that of other single-stage liquefaction materials. The degree of alkylation in these materials was determined to be greater than in the SRC and less than in the EDS process distillate cuts. 13 references, 8 figures, 11 tables.

  10. Hydrothermal Liquefaction of Agricultural and Biorefinery Residues Final Report – CRADA #PNNL/277

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.; Neuenschwander, Gary G.; Hart, Todd R.; Rotness, Leslie J.; Zacher, Alan H.; Fjare, K. A.; Dunn, B. C.; McDonald, S. L.; Dassor, G.

    2010-07-28

    This project was performed as a Cooperative Research and Development Agreement (CRADA) with the participants: Archer-Daniels-Midland Company (ADM), ConocoPhillips (COP), and Pacific Northwest National Laboratory (PNNL). Funding from the federal government was provided by the Office of the Biomass Program within the Energy Efficiency and Renewable Energy assistant secretariat as part of the Thermochemical Conversion Platform. The three-year project was initiated in August 2007 with formal signing of the CRADA (#PNNL/277) in March 3, 2008 with subsequent amendments approved in November of 2008 and August of 2009. This report describes the results of the work performed by PNNL and the CRADA partners ADM and COP. It is considered Protected CRADA Information and is not available for public disclosure. The work conducted during this project involved developing process technology at PNNL for hydrothermal liquefaction (HTL) of agricultural and biorefinery residues and catalytic hydrothermal gasification (CHG) of the aqueous byproduct from the liquefaction step. Related work performed by the partners included assessment of aqueous phase byproducts, hydroprocessing of the bio-oil product and process analysis and economic modeling of the technology.

  11. Assessment of liquefaction potential index for Mumbai city

    Directory of Open Access Journals (Sweden)

    J. Dixit

    2012-09-01

    Full Text Available Mumbai city is the financial capital of India and is fifth most densely populated city in the world. Seismic soil liquefaction is evaluated for Mumbai city in terms of the factors of safety against liquefaction (FS along the depths of soil profiles for different earthquakes with 2% probability of exceedance in 50 yr using standard penetration test (SPT-based simplified empirical procedure. This liquefaction potential is evaluated at 142 representative sites in the city using the borehole records from standard penetration tests. Liquefaction potential index (LPI is evaluated at each borehole location from the obtained factors of safety (FS to predict the potential of liquefaction to cause damage at the surface level at the site of interest. Spatial distribution of soil liquefaction potential is presented in the form of contour maps of LPI values. As the majority of the sites in the city are of reclaimed land, the vulnerability of liquefaction is observed to be very high at many places.

  12. Liquefaction evaluation of dam foundation soils considering overlying structure

    Institute of Scientific and Technical Information of China (English)

    Gang Wang a; Xing Wei b; Hanlong Liu a

    2015-01-01

    The liquefaction analysis procedure conducted at a dam foundation associated with a layer of liquefiable sand is presented. In this case, the effects of the overlying dam and an embedded diaphragm wall on liquefaction potential of foundation soils are considered. The analysis follows the stress-based approach which compares the earthquake-induced cyclic stresses with the cyclic resistance of the soil, and the cyclic resistance of the sand under complex stress condition is the key issue. Comprehensive laboratory monotonic and cyclic triaxial tests are conducted to evaluate the static characteristics, dynamic char-acteristics and the cyclic resistance against liquefaction of the foundation soils. The distribution of the factor of safety considering liquefaction is given. It is found that the zones beneath the dam edges and near the upstream of the diaphragm wall are more susceptible to liquefaction than in free field, whereas the zone beneath the center of the dam is less susceptible to liquefaction than in free field. According to the results, the strategies of ground improvement are proposed to mitigate the liquefaction hazards.

  13. Combustion, pyrolysis, gasification, and liquefaction of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Reed, T.B.

    1980-09-01

    All the products now obtained from oil can be provided by thermal conversion of the solid fuels biomass and coal. As a feedstock, biomass has many advantages over coal and has the potential to supply up to 20% of US energy by the year 2000 and significant amounts of energy for other countries. However, it is imperative that in producing biomass for energy we practice careful land use. Combustion is the simplest method of producing heat from biomass, using either the traditional fixed-bed combustion on a grate or the fluidized-bed and suspended combustion techniques now being developed. Pyrolysis of biomass is a particularly attractive process if all three products - gas, wood tars, and charcoal - can be used. Gasification of biomass with air is perhaps the most flexible and best-developed process for conversion of biomass to fuel today, yielding a low energy gas that can be burned in existing gas/oil boilers or in engines. Oxygen gasification yields a gas with higher energy content that can be used in pipelines or to fire turbines. In addition, this gas can be used for producing methanol, ammonia, or gasoline by indirect liquefaction. Fast pyrolysis of biomass produces a gas rich in ethylene that can be used to make alcohols or gasoline. Finally, treatment of biomass with high pressure hydrogen can yield liquid fuels through direct liquefaction.

  14. Combustion, pyrolysis, gasification, and liquefaction of biomas

    Science.gov (United States)

    Reed, T. B.

    1980-09-01

    The advantages of biomass as a feedstock are examined and biomass conversion techniques are described. Combustion is the simplest method of producing heat from biomass, using either the traditional fixed bed combustion on a grate or the fluidized bed and suspended combustion techniques now being developed. Pyrolysis of biomass is a particularly attractive process if all three products gas, wood tars, and charcoal can be used. Gasification of biomass with air is perhaps the most flexible and best developed process for conversion of biomass to fuel, yielding a low energy gas that can be burned in existing gas/oil boilers or in engines. Oxygen gasification yields a gas with higher energy content that can be used in pipelines or to fire turbines. In addition, this gas can be used for producing methanol, ammonia, or gasoline by indirect liquefaction. Fast pyrolysis of biomass produces a gas rich in ethylene that can be used to make alcohols or gasoline. Finally, treatment of biomass with high pressure hydrogen can yield liquid fuels through direct liquefaction.

  15. 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.

  16. A multi-stage heuristic algorithm for matching problem in the modified miniload automated storage and retrieval system of e-commerce

    Science.gov (United States)

    Wang, Wenrui; Wu, Yaohua; Wu, Yingying

    2016-05-01

    E-commerce, as an emerging marketing mode, has attracted more and more attention and gradually changed the way of our life. However, the existing layout of distribution centers can't fulfill the storage and picking demands of e-commerce sufficiently. In this paper, a modified miniload automated storage/retrieval system is designed to fit these new characteristics of e-commerce in logistics. Meanwhile, a matching problem, concerning with the improvement of picking efficiency in new system, is studied in this paper. The problem is how to reduce the travelling distance of totes between aisles and picking stations. A multi-stage heuristic algorithm is proposed based on statement and model of this problem. The main idea of this algorithm is, with some heuristic strategies based on similarity coefficients, minimizing the transportations of items which can not arrive in the destination picking stations just through direct conveyors. The experimental results based on the cases generated by computers show that the average reduced rate of indirect transport times can reach 14.36% with the application of multi-stage heuristic algorithm. For the cases from a real e-commerce distribution center, the order processing time can be reduced from 11.20 h to 10.06 h with the help of the modified system and the proposed algorithm. In summary, this research proposed a modified system and a multi-stage heuristic algorithm that can reduce the travelling distance of totes effectively and improve the whole performance of e-commerce distribution center.

  17. Earthquake Risk - EARTHQUAKE_LIQUEFACTION_POTENTIAL_MM81_IN: Liquefaction Potential of Surficial Materials in Indiana (Indiana Geological Survey, 1:500,000, Polygon Shapefile)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — EARTHQUAKE_LIQUEFACTION_POTENTIAL_MM81_IN is a polygon shapefile that shows highly generalized categories (low, moderate, and high) of liquefaction potential, based...

  18. Effect of in-situ solvent soaking and heating pre-treatment on coal conversion and oil yield during liquefaction of demineralized low-rank Malaysian coal

    Energy Technology Data Exchange (ETDEWEB)

    M.A.M. Ishak; M.F. Abdullah; K. Ismail; M.O.A. Kadir; A.R. Mohamed [University Technology MARA, Perlis (Malaysia). Fuel Combustion Research Laboratory, Faculty of Applied Sciences

    2005-07-01

    The effect of in-situ solvent soaking and heating (SSH) pre-treatment on demineralized low-rank Malaysian coal towards coal conversion and oil yield during direct liquefaction was investigated. Demineralization of coal was carried out by leaching with strong protic acids such as HCl, HF and HNO{sub 3} whereby more than 95 % of mineral content in the coal was reduced. Apparently, the mineral matter that was removed by the HCl treatment (i.e. cationics) exhibits more catalytic effect during the liquefaction process. The reduction in the mineral content increased the coal porosity that enabled the solvent to penetrate into the coal macropores during the SSH pre-treatment process. The results of liquefaction on the pre-treated SSH demineralized coal at 420{sup o}C and at 4 MPa, however show comparable amount of coal conversion with slightly lower amount of oil yield being obtained with comparison to the raw and SSH-raw coals. Thus, besides the in-situ solvent soaking and heating pre-treatment, the presence of mineral matters in coal prove to be beneficial during coal liquefaction process.

  19. Vibrating Liquefaction Experiment and Mechanism Study in Saturated Granular Media

    Institute of Scientific and Technical Information of China (English)

    Li Jianhua; Xu Ming; Ju Haiyan; Zhao Jiangqian; Huang Hongyuan; Sun Yezhi

    2006-01-01

    By the vibrating liquefaction experiment of tailings and fine-ores of iron, it is observed and noted that the change of pore water pressure when the vibrating liquefaction takes place. Based on relevant suppositions, the equation of wave propagation in saturated granular media is obtained. This paper postulates the potential vector equation and the velocity expression of three kinds of body waves under normal conditions.Utilizing the wave theory and the experimental results, the influence of three body waves on pore water pressure and granules has been analyzed in detail. This revealed the rapid increment mechanism of pore water pressure and the wave mechanism of vibrating liquefaction.

  20. Direct coal liquefaction baseline design and system analysis. Quarterly report, January--March 1991

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The primary objective of the study is to develop a computer model for a base line direct coal liquefaction design based on two stage direct coupled catalytic reactors. This primary objective is to be accomplished by completing the following: a base line design based on previous DOE/PETC results from Wilsonville pilot plant and other engineering evaluations; a cost estimate and economic analysis; a computer model incorporating the above two steps over a wide range of capacities and selected process alternatives; a comprehensive training program for DOE/PETC Staff to understand and use the computer model; a thorough documentation of all underlying assumptions for baseline economics; and a user manual and training material which will facilitate updating of the model in the future.

  1. A Review of Hydrothermal Liquefaction Bio-Crude Properties and Prospects for Upgrading to Transportation Fuels

    Directory of Open Access Journals (Sweden)

    Jerome A. Ramirez

    2015-07-01

    Full Text Available Hydrothermal liquefaction (HTL presents a viable route for converting a vast range of materials into liquid fuel, without the need for pre-drying. Currently, HTL studies produce bio-crude with properties that fall short of diesel or biodiesel standards. Upgrading bio-crude improves the physical and chemical properties to produce a fuel corresponding to diesel or biodiesel. Properties such as viscosity, density, heating value, oxygen, nitrogen and sulphur content, and chemical composition can be modified towards meeting fuel standards using strategies such as solvent extraction, distillation, hydrodeoxygenation and catalytic cracking. This article presents a review of the upgrading technologies available, and how they might be used to make HTL bio-crude into a transportation fuel that meets current fuel property standards.

  2. Wilsonville Advanced Coal Liquefaction Research and Development Facility, Wilsonville, Alabama. Topical report No. 14. Catalyst activity trends in two-stage coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    1984-02-01

    The Two Stage Coal Liquefaction process became operational at Wilsonville in May 1981, with the inclusion of an H-OIL ebullated-bed catalytic reactor. The two stage process was initially operated in a nonintegrated mode and has recently been reconfigurated to fully integrate the thermal and the catalytic stages. This report focuses on catalyst activity trends observed in both modes of operation. A literature review of relevant catalyst screening studies in bench-scale and PDU units is presented. Existing kinetic and deactivation models were used to analyze process data over an extensive data base. Based on the analysis, three separate, application studies have been conducted. The first study seeks to elucidate the dependence of catalyst deactivation rate on type of coal feedstock used. A second study focuses on the significance of catalyst type and integration mode on SRC hydrotreatment. The third study presents characteristic deactivation trends observed in integrated operation with different first-stage thermal severities. In-depth analytical work was conducted at different research laboratories on aged catalyst samples from Run 242. Model hydrogenation and denitrogenation activity trends are compared with process activity trends and with changes observed in catalyst porosimetric properties. The accumulation of metals and coke deposits with increasing catalyst age, as well as their distribution across a pellet cross-section, are discussed. The effect of catalyst age and reactor temperature on the chemical composition of flashed bottoms product is addressed. Results from regenerating spent catalysts are also presented. 35 references, 31 figures, 18 tables.

  3. Kinetics of the pyrolysis of arundo, sawdust, corn stover and switch grass biomass by thermogravimetric analysis using a multi-stage model.

    Science.gov (United States)

    Biney, Paul O; Gyamerah, Michael; Shen, Jiacheng; Menezes, Bruna

    2015-03-01

    A new multi-stage kinetic model has been developed for TGA pyrolysis of arundo, corn stover, sawdust and switch grass that accounts for the initial biomass weight (W0). The biomass were decomposed in a nitrogen atmosphere from 23°C to 900°C in a TGA at a single 20°C/min ramp rate in contrast with the isoconversion technique. The decomposition was divided into multiple stages based on the absolute local minimum values of conversion derivative, (dx/dT), obtained from DTG curves. This resulted in three decomposition stages for arundo, corn stover and sawdust and four stages for switch grass. A linearized multi-stage model was applied to the TGA data for each stage to determine the pre-exponential factor, activation energy, and reaction order. The activation energies ranged from 54.7 to 60.9 kJ/mol, 62.9 to 108.7 kJ/mol, and 18.4 to 257.9 kJ/mol for the first, second and the third decomposition stages respectively.

  4. Selection of the optimal completion of horizontal wells with multi-stage hydraulic fracturing of the low-permeable formation, field C

    Science.gov (United States)

    Bozoev, A. M.; Demidova, E. A.

    2016-03-01

    At the moment, many fields of Western Siberia are in the later stages of development. In this regard, the multilayer fields are actually involved in the development of hard to recover reserves by conducting well interventions. However, most of these assets may not to be economical profitable without application of horizontal drilling and multi-stage hydraulic fracturing treatment. Moreover, location of frac ports in relative to each other, number of stages, volume of proppant per one stage are the main issues due to the fact that the interference effect could lead to the loss of oil production. The optimal arrangement of horizontal wells with multi-stage hydraulic fracture was defined in this paper. Several analytical approaches have been used to predict the started oil flow rate and chose the most appropriate for field C reservoir J1. However, none of the analytical equations could not take into account the interference effect and determine the optimum number of fractures. Therefore, the simulation modelling was used. Finally, the universal equation is derived for this field C, the reservoir J1. This tool could be used to predict the flow rate of the horizontal well with hydraulic fracturing treatment on the qualitative level without simulation model.

  5. An Advanced Wet Expansion Turbine for Hydrogen Liquefaction Project

    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...

  6. 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.

  7. Coal liquefaction. Quarterly report, October--December 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-05-01

    Progress on seventeen projects related to coal liquefaction or the upgrading of coal liquids and supported by US DOE is reported with emphasis on funding, brief process description history and current progress. (LTN)

  8. Self-organized criticality of liquefaction in saturated granules

    Institute of Scientific and Technical Information of China (English)

    吴爱祥; 孙业志; 李青松

    2003-01-01

    Utilizing the dissipative structure theory, the evolutionary process of vibrating liquefaction in saturatedgranules was analyzed. When the irreversible force increases to some degree, the system will be in a state far fromequilibrium, and the new structure probably occurs. According to synergetics, the equation of liquefaction evolutionwas deduced, and the evolutionary process was analyzed by dynamics. The evolutionary process of vibrating lique-faction is a process in which the period doubling accesses to chaos, and the fluctuation is the original driving force ofsystem evolution. The liquefaction process was also analyzed by fractal geometry. The steady process of vibratingliquefaction obeys the scaling form, and shows self-organized criticality in the course of vibration. With the incre-ment of the recurrence number, the stress of saturated granules will decrease rapidly or lose completely, and thestrain will increase rapidly, so that the granules can not sustain load and the "avalanche" phenomenon takes place.

  9. 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.

  10. 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...... is proposed in this paper. To meet this objective, an effort is made to introduce a total of 30 boreholes data in an area of 7 km2 which includes the results of field tests into the neural network model and the prediction of artificial neural network is checked in some test boreholes, finally the 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...

  11. An Advanced Wet Expansion Turbine for Hydrogen Liquefaction Project

    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...

  12. Asspects Concerning the Improvement of Soils Against Liquefaction

    Directory of Open Access Journals (Sweden)

    Costel Pleşcan

    2010-01-01

    Full Text Available The specialized literature concerning the Geotechnical Engineering Field indicates the problems due to soil liquefaction and the aggravating consequences that liquefaction phenomenon may cause to buildings. Some procedures of foundation soil improvement for both existing and future foundations are presented. The paper also presents three soil remediation methods involving a low level of vibration generated in the process of foundation soil improvement and two case studies representing the usual method in Romania.

  13. 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.

  14. Liquefaction of Sand under Low Confining Pressure

    Institute of Scientific and Technical Information of China (English)

    YANG Shaoli; Rolf Sandven; Lars Grande

    2003-01-01

    Undrained behaviour of sand under low cell pressure was studied in static and cyclic triaxial tests. It was found that very loose sand liquefies under static loading with the relative density being a key parameter for the undrained behaviour of sand. In cyclic triaxial tests, pore water pressures built up during the cyclic loading and exceeded the confining cell pressure. This process was accompanied by a large sudden increase in axial deformation. The necessary number of cycles to obtain liquefaction was related to the confining cell pressure, the amplitude of cyclic loading and the relative density of sand.In addition, the patterns of pore water pressure response are different from those of sand samples with different relative densities. The test results are very useful for expounding scour mechanism around coastal structures since they relate to the low stress behaviour of the sand.

  15. Liquefaction mathematical analysis for improvement structures stability

    Directory of Open Access Journals (Sweden)

    Azam Khodashenas Pelko

    2010-10-01

    Full Text Available The stability of any structure is possible if foundation is appropriately designed. The Bandar abbas is the largest and most important port of Iran, with high seismicity and occurring strong earthquakes in this territory, the soil mechanical properties of different parts of city have been selected as the subject of current research. The data relating to the design of foundation for improvement of structure at different layer of subsoil have been collected and, accordingly, soil mechanical properties have been evaluated. The results of laboratory experiments can be used for evaluation of geotechnical characteristics of urban area for development a region with high level of structural stability. Ultimately, a new method for calculation of liquefaction force is suggested. It is applicable for improving geotechnical and structure codes and also for reanalysis of structure stability of previously constructed buildings.

  16. 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.

  17. 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.

  18. Intensity measures for seismic liquefaction hazard evaluation of sloping site

    Institute of Scientific and Technical Information of China (English)

    陈志雄; 程印; 肖杨; 卢谅; 阳洋

    2015-01-01

    This work investigates the correlation between a large number of widely used ground motion intensity measures (IMs) and the corresponding liquefaction potential of a soil deposit during earthquake loading. In order to accomplish this purpose the seismic responses of 32 sloping liquefiable site models consisting of layered cohesionless soil were subjected to 139 earthquake ground motions. Two sets of ground motions, consisting of 80 ordinary records and 59 pulse-like near-fault records are used in the dynamic analyses. The liquefaction potential of the site is expressed in terms of the the mean pore pressure ratio, the maximum ground settlement, the maximum ground horizontal displacement and the maximum ground horizontal acceleration. For each individual accelerogram, the values of the aforementioned liquefaction potential measures are determined. Then, the correlation between the liquefaction potential measures and the IMs is evaluated. The results reveal that the velocity spectrum intensity (VSI) shows the strongest correlation with the liquefaction potential of sloping site. VSI is also proven to be a sufficient intensity measure with respect to earthquake magnitude and source-to-site distance, and has a good predictability, thus making it a prime candidate for the seismic liquefaction hazard evaluation.

  19. 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.

  20. Liquefaction of Fir Sawdust Catalyzed by [ Psmim] HSO4 and Characterization of Liquefaction Products%[Psmim]HSO4离子液体催化液化木材及其产物表征

    Institute of Scientific and Technical Information of China (English)

    郑怀玉; 卢泽湘; 范立维; 黄彪; 廖益强; 胡阳

    2014-01-01

    1-( 4-sulfopropyl )-3-methylimidazolium hydrosulfate ( [ Psmim ] HSO4 ) was synthesized and its structure was characterized by FT-IR and 13C NMR . The catalytic performance of [ Psmim ] HSO4 in liquefaction of fir sawdust was preliminarily investigated using 1-octanol as solvent. The liquefaction products were characterized by FT-IR, XRD, TG, GC-MS. The structure of the synthesized ionic liquid was confirmed by the analysis of FT-IR and 13C NMR characterization. The liquefaction experimental results showed that the ionic liquid exhibited a good catalytic performance for the liquefaction of sawdust. The conversion of 66. 5% was achieved when 8. 6 mmol of catalyst was used with application of 10 g fir sawdust and 60 g 1-octanol at the temperature of 150 ℃ for 60 min. The surface of the solid residue was covered with lignin derivatives. The light oil mainly contained the liquefied products originated from cellulose and hemicellulose, and the heavy oil consisted mainly of the degradation products from lignin.%合成了1-磺酸丙基-3-甲基咪唑硫酸氢盐离子液体([ Psmim] HSO4),对其结构进行了傅里叶红外光谱( FT-IR)和核磁共振(13C NMR)表征。以正辛醇为溶剂,初步考察了该离子液体对杉木屑液化的催化性能,并对残渣、重油和轻油液化产物进行了FT-IR、X射线粉末衍射( XRD)、热重分析( TG)、气质联用( GC-MS)表征。 FT-IR和13C NMR分析结果证实了合成产物与目标离子液体结构一致。液化实验结果表明该离子液体具有较好的催化液化性能,10 g杉木屑、60 g正辛醇在催化剂用量8.6 mmol、150℃、60 min条件下,木屑的液化率达66.5%。液化残渣表面的木质素衍生物含量高;轻油主要由纤维素和半纤维素的液化产物组成,重油主要由木质素的液化产物组成。

  1. Liquefaction severity map for Aksaray city center (Central Anatolia, Turkey

    Directory of Open Access Journals (Sweden)

    A. Yalcin

    2008-07-01

    Full Text Available Turkey having a long history of large earthquakes have been subjected to progressive adjacent earthquakes. Starting in 1939, the North Anatolian Fault Zone (NAFZ produced a sequence of major earthquakes, of which the Mw 7.4 earthquake that struck western Turkey on 17 August 1999. Following the Erzincan earthquake in 1992, the soil liquefaction has been crucial important in the agenda of Turkey. Soil liquefaction was also observed widely during the Marmara and the Düzce Earthquake in 1999 (Sönmez, 2003. Aksaray city center locates in the central part of Turkey and the Tuzgolu Fault Zone passes through near the city center. The fault zone has been generated to moderate magnitude earthquakes. The geology of the Aksaray province basin contains Quaternary alluvial deposits formed by gravel, sand, silt, and clay layers in different thickness. The Tuzgolu Fault Zone (TFZ came into being after the sedimetation of alluvial deposits. Thus, the fault is younger from lithological units and it is active. In addition, the ground water level is very shallow, within approximately 3 m from the surface. In this study, the liquefaction potential of the Aksaray province is investigated by recent procedure suggested by Sonmez and Gokceoglu (2005. For this purpose, the liquefaction susceptibility map of the Aksaray city center for liquefaction is presented. In the analysis, the input parameters such as the depth of the upper and lower boundaries of soil layer, SPT-N values, fine content, clay content and the liquid limit were used for all layers within 20 m from the surface. As a result, the category of very high susceptibility liquefaction class was not observed for the earthquake scenario of Ms=5.2, 4.9% of the study area has high liquefaction susceptibility. The percentage of the moderately, low, and very low liquefied areas are 28.2%, 30.2%, and 36.3%, respectively. The rank of non-liquefied susceptibility area is less than 1%.

  2. A multi-stage compartmental model for HIV-infected individuals: II--application to insurance functions and health-care costs.

    Science.gov (United States)

    Billard, L; Dayananda, P W A

    2014-03-01

    Stochastic population processes have received a lot of attention over the years. One approach focuses on compartmental modeling. Billard and Dayananda (2012) developed one such multi-stage model for epidemic processes in which the possibility that individuals can die at any stage from non-disease related causes was also included. This extra feature is of particular interest to the insurance and health-care industries among others especially when the epidemic is HIV/AIDS. Rather than working with numbers of individuals in each stage, they obtained distributional results dealing with the waiting time any one individual spent in each stage given the initial stage. In this work, the impact of the HIV/AIDS epidemic on several functions relevant to these industries (such as adjustments to premiums) is investigated. Theoretical results are derived, followed by a numerical study.

  3. Process Development for Hydrothermal Liquefaction of Algae Feedstocks in a Continuous-Flow Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.; Hart, Todd R.; Schmidt, Andrew J.; Neuenschwander, Gary G.; Rotness, Leslie J.; Olarte, Mariefel V.; Zacher, Alan H.; Albrecht, Karl O.; Hallen, Richard T.; Holladay, Johnathan E.

    2013-10-01

    Wet algae slurries can be converted into an upgradeable biocrude by hydrothermal liquefaction (HTL). High levels of carbon conversion to gravity-separable biocrude product were accomplished at relatively low temperature (350 °C) in a continuous-flow, pressurized (sub-critical liquid water) environment (20 MPa). As opposed to earlier work in batch reactors reported by others, direct oil recovery was achieved without the use of a solvent and biomass trace components were removed by processing steps so that they did not cause process difficulties. High conversions were obtained even with high slurry concentrations of up to 35 wt% of dry solids. Catalytic hydrotreating was effectively applied for hydrodeoxygenation, hydrodenitrogenation, and hydrodesulfurization of the biocrude to form liquid hydrocarbon fuel. Catalytic hydrothermal gasification was effectively applied for HTL byproduct water cleanup and fuel gas production from water soluble organics, allowing the water to be considered for recycle of nutrients to the algae growth ponds. As a result, high conversion of algae to liquid hydrocarbon and gas products was found with low levels of organic contamination in the byproduct water. All three process steps were accomplished in bench-scale, continuous-flow reactor systems such that design data for process scale-up was generated.

  4. Coal liquefaction studies using phosphoric acid at moderate temperatures and pressures

    Energy Technology Data Exchange (ETDEWEB)

    McLean, J.B.; Vermeulen, T.

    1977-12-01

    Concentrated phosphoric acid solutions (65-100% H/sub 3/PO/sub 4/) were studied as a potential homogenous catalytic medium for coal liquefaction at temperatures of up 250/sup 0/C and hydrogen pressures up to 600 psig. Possible catalytic additives, both organic and inorganic, were investigated. Sulfuric acid and molten phosphate and sulfate salt systems were also briefly studied. Sodium pyrophosphate was found to be a beneficial additive to phosphoric acid, in that it reduces the tendency toward foaming upon contacting coal with hot acid, and was used in all subsequent experiments. The materials were relatively ineffective in liquefying coals, except with certain organic additives. Approximately 30% of the sulfur in coal is removed by phosphoric acid treatment, while no effect on nitrogen content is evidenced. Some deashing occurs, with AlCa components most affected. Phosphorus is chemically incorporated into the product coal at levels of 2% or less with most of the incorporated P ending up in the pyridine extract. B.E.T. surface area and scanning electron microscope studies indicate that increased extraction yields of product coals are due more to chemical effects than simply to exposure of more surface area to the extraction solvent used.

  5. Safety Assessment of Nuclear Power Plants for Liquefaction Consequences

    Directory of Open Access Journals (Sweden)

    Tamás János Katona

    2015-01-01

    Full Text Available In case of some nuclear power plants constructed at the soft soil sites, liquefaction should be analysed as beyond design basis hazard. The aim of the analysis is to define the postevent condition of the plant, definition of plant vulnerabilities, and identification of the necessary measures for accident management. In the paper, the methodology of the analysis of liquefaction effects for nuclear power plants is outlined. The procedure includes identification of the scope of the safety analysis and the acceptable limit cases for plant structures having different role from accident management point of view. Considerations are made for identification of dominating effects of liquefaction. The possibility of the decoupling of the analysis of liquefaction effects from the analysis of vibratory ground motion is discussed. It is shown in the paper that the practicable empirical methods for definition of liquefaction susceptibility provide rather controversial results. Selection of method for assessment of soil behaviour that affects the integrity of structures requires specific considerations. 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.

  6. THERMOGRAVIMETRIC STUDIES ON CONDENSED WOOD RESIDUES IN POLYHYDRIC ALCOHOLS LIQUEFACTION

    Directory of Open Access Journals (Sweden)

    Mehmet Hakki Alma

    2011-02-01

    Full Text Available To further clarify reasons for formation of condensed residues during the last stage of wood liquefaction in the medium of polyhydric alcohols and sulfuric acid catalyst, the weight loss behaviors and thermal reaction kinetics of condensed residues were studied by thermogravimetric analysis (TGA. Simultaneously, chemical methods were used to analyze the contents of lignin, cellulose, and holocellulose in the condensed residues. For all the unliquefied wood residues, the contents of cellulose decreased, and the residual ratios after TGA pyrolysis and the contents of lignin increased as a function of liquefaction time. Moreover, the highest weight loss rate went gradually to the higher temperature region after the liquefaction time and heating rate were extended. The values for apparent activation energy were lower at 150 minutes and 180 minutes and higher at 25 minutes. Liquefaction time had a smaller effect on the pyrolysis mechanism, as revealed by TGA. In conclusion, the thermal stabilities of condensed residues were higher than those of decomposed residues and wood. The condensation reaction occurred mainly during wood liquefaction, and condensed residues resulted possibly from mutual reaction among small molecules from decomposed lignin.

  7. Catalytic conversion of biomass to fuels. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Garten, R. L.; Ushiba, K. K.; Cooper, M.; Mahawili, I.

    1978-01-01

    This report presents an assessment and perspective concerning the application of catalytic technologies to the thermochemical conversion of biomass resources to fuels. The major objectives of the study are: to provide a systematic assessment of the role of catalysis in the direct thermochemical conversion of biomass into gaseous and liquid fuels; to establish the relationship between potential biomass conversion processes and catalytic processes currently under development in other areas, with particular emphasis on coal conversion processes; and to identify promising catalytic systems which could be utilized to reduce the overall costs of fuels production from biomass materials. The report is divided into five major parts which address the above objectives. In Part III the physical and chemical properties of biomass and coal are compared, and the implications for catalytic conversion processes are discussed. With respect to chemical properties, biomass is shown to have significant advantages over coal in catalytic conversion processes because of its uniformly high H/C ratio and low concentrations of potential catalyst poisons. The physical properties of biomass can vary widely, however, and preprocessing by grinding is difficult and costly. Conversion technologies that require little preprocessing and accept a wide range of feed geometries, densities, and particle sizes appear desirable. Part IV provides a comprehensive review of existing and emerging thermochemical conversion technologies for biomass and coal. The underlying science and technology for gasification and liquefaction processes are presented.

  8. Low severity coal liquefaction promoted by cyclic olefins. Quarterly report, January--March 1993

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, C.W.

    1993-07-01

    The combination of some of these methods could further improve low severity conversion. It seems logical that a combination of a proven pretreatment technique with a good dissolution catalyst or a good hydrogen donor would increase reactivity. The importance of surface chemistry with yield and nature of reactions shown in early research indicates the physical importance of pretreatment. Swelling of the coal with an organic solvent improves the contact. This good contact is also important to slowing retrogressive reactions. The best conversions come when the initial products of liquefaction are preserved. In addition to the physical importance of pretreatment, there is a chemical advantage. Shams saw not only the effect of minimization of organic oxygen coupling reactions, but with his process there also seemed to be a demineralization. The minerals removed the catalysts for retrogressive reactions. The chemistry of liquefaction is still not well understood. Stansberry`s attempt to determine whether catalysts liberate species or just further decomposition was largely inconclusive. There was improvement in conversion so the catalysts seemingly assisted in bond breakage. These good catalytic effects were also seen in the work involving coprocessing. The most compelling factor in each of these procedures, is the ability of the coal to receive the hydrogen that it needs to be liquefied. Bedell and Curtis (1991) found that cyclic olefins gave their hydrogen up much more readily than did hydroaromatics. The coal conversion was a significantly improved. The combination of retrogressive reaction suppression and good hydrogen donability should provide for good coal conversion. It was this reasoning that influenced the decision to investigate a combination of the HCl/methanol pretreatment and the usage of cyclic olefins as hydrogen donors. The increased reactivity of the pretreated coal should enhance the effect of the hydrogen donability of the cyclic olefins.

  9. Effects of catalysts on liquefaction of Agaricus versicolor (L.)

    Science.gov (United States)

    Durak, Halil

    2016-04-01

    Supercritical liquefaction process is used for producing energy from biomass. The common reaction conditions for supercritical liquefaction process are the 240-380 °C temperature range and 5-20 Mpa pressure values range. Agaricus versicolor (L.) was liquefied by acetone in an autoclave (75 mL) under high pressure with (aluminium oxide and calcium hydroxide) and without catalyst at 290 °C for producing bio-oil. The products of liquefaction (bio-oil) were analysed and characterized using various methods including elemental analysis, Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry. GC-MS identified 27 different compounds in the bio-oils obtained at 290 °C.

  10. 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

  11. 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.

  12. 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.

  13. A modified criterion for wave-induced momentary liquefaction of sandy seabed

    Directory of Open Access Journals (Sweden)

    Wen-Gang Qi

    2015-01-01

    Full Text Available The assessment of the wave-induced soil liquefaction plays a key role in the geotechnical design for offshore foundations. The underlying shortcomings of the existing momentary liquefaction criteria are identified and clarified by mechanism analyses and the recent field observations. A modified criterion for the wave-induced momentary liquefaction of a sandy seabed is given to describe the vertical pore-pressure distributions. An improved approximation of the momentary liquefaction depth is further presented. Parametric study of the effects of the saturation degree of soils indicates that this modification is significant for the evaluation of wave-induced momentary liquefaction.

  14. 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.

  15. 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...

  16. 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.

  17. Catalysts and process developments for two-stage liquefaction. Final technical report, October 1, 1989--September 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Cronauer, D.C.; Swanson, A.J.; Sajkowski, D.J.

    1992-12-31

    Research in this project centered upon developing and evaluating catalysts and process improvements for coal liquefaction in the two-stage, close-coupled catalytic process. The major results are summarized here and they are described in more detail under each Task. In tasks for coal pretreatment and beneficiation, it was shown for coal handling that drying of both lignite or subbituminous coals using warm air, vacuum oven or exposing to air for long time was detrimental to subsequent liquefaction. Both laboratory and bench-scale beneficiations indicated that in order to achieve increased liquefaction yield for Illinois No. 6 bituminous coal, size separation with in sink-float technique should be used. For subbituminous coal, the best beneficiation was aqueous SO{sub 2} treatment, which reduced mineral matter. In the case of lignite, the fines should be rejected prior to aqueous SO{sub 2} treatment and sink-float gravity separation. In liquefying coals with supported catalysts in both first and second stages, coal conversion was highest (93%) with Illinois No. 6 coal, which also had the highest total liquid yield of 80%, however, the product contained unacceptably high level of resid (30%). Both low rank coals gave lower conversion (85--87%) and liquid yields (57--59%), but lighter products (no resid). The analysis of spent first stage catalysts indicated significant sodium and calcium deposits causing severe deactivation. The second stage catalysts were in better condition showing high surface areas and low coke and metal deposits. The use of dispersed catalyst in the first stage would combat the severe deactivation.

  18. 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.

  19. Optimization of design and operating parameters on the year round performance of a multi-stage evacuated solar desalination system using transient mathematical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, P. Vishwanath; Kaviti, Ajay Kumar; Prakash, Om [Department of Mechanical Engineering, Sagar Institute of Science and Technology, Gandhinagar, Bhopal, M.P. (India); Reddy, K.S. [Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai (India)

    2012-07-01

    The available fresh water resources on the earth are limited. About 79% of water available on the earth is salty, only one percent is fresh and the rest 20% is brackish. Desalination of brackish or saline water is a good method to obtain fresh water. Conventional desalination systems are energy intensive. Solar desalination is a cost effective method to obtain potable water because of freely available clean and green energy source. In this paper, a transient mathematical model was developed for the multi-stage evacuated solar desalination system to achieve the optimum system configuration for the maximum year round performance and distillate yield. The effect of various design and operating parameters on the thermal characteristics and performance of the system were analyzed. It was found that an optimum configuration of four stages with 100mm gap between them when supplied with a mass flow rate of 55kg/m2/day would result in best performance throughout the year. The maximum and minimum yields of 28.044 kg/m2/day and 13.335 kg/m2/day for fresh water at a distillate efficiency of 50.989% and 24.245% and overall thermal efficiency of 81.171% and 40.362% are found in the months of March and December respectively owing to the climatic conditions. The yield decreases to 18.614 kg/m2/day and 9.791 kg/m2/day for brine solution at a distillate efficiency of 33.844% and 17.802% and overall thermal efficiency of 53.876% and 29.635% for March and December respectively The maximum yield of 53.211 kg/m2/day is found in March at an operating pressure of 0.03 bar. The multi-stage evacuated solar desalination system is economically viable and can meet the needs of rural and urban communities to necessitate 10 to 30 kg per day of fresh water.

  20. Modeling and optimization of unbalanced multi-stage logistic system%非平衡多阶段物流系统建模与优化方法

    Institute of Scientific and Technical Information of China (English)

    徐杭; 徐榕; 叶庆泰

    2005-01-01

    To decompose an unbalanced multi-stage logistic system to multiple independent single-stage logistic systems,a new notion of parameterized interface distribution is presented.For encoding the logistic pattern on each stage,the Prüfer number is used.With the improved decoding procedure,any Prüfer number produced stochastically can be decoded to a feasible logistic pattern,which can match with the capacities of the nodes of the logistic system.With these two innovations,a new modeling method based on parameterized interface distribution and the Prüfer number coding is put forward.The corresponding genetic algorithm,named as PIP-GA,can find better solutions and require less computational time than st-GA.Although requiring a little more consumption of memory,PIP-GA is still an efficient and robust method in the modeling and optimization of unbalanced multi-stage logistic systems.%首先提出了参数化界面分布的新概念,将一个非平衡多阶段物流系统转化为多个相互独立的单一阶段物流系统,然后采用Prüfer数对每个阶段上的物流模式进行编码.通过一种改进的解码方法,任何一个随机产生的Prüfer数都能够被解码为一个与物流系统的节点容量相匹配的可行的物流模式.基于这2点创新,建立了一种新的基于参数化界面分布和Prüfer数编码的系统建模方法,相应的遗传算法称为PIP-GA方法.与st-GA方法相比,PIP-GA不但具有更好的优化结果,而且需要的计算时间更少;虽然所需的存储空间有所增加,PIP-GA仍然是一种有效而稳健的非平衡多阶段物流系统建模与优化方法.

  1. Optimization of design and operating parameters on the year round performance of a multi-stage evacuated solar desalination system using transient mathematical analysis

    Directory of Open Access Journals (Sweden)

    P. Vishwanath Kumar, Ajay Kumar Kaviti, Om Prakash1, K.S. Reddy

    2012-01-01

    Full Text Available The available fresh water resources on the earth are limited. About 79% of water available on the earth is salty, only one percent is fresh and the rest 20% is brackish. Desalination of brackish or saline water is a good method to obtain fresh water. Conventional desalination systems are energy intensive. Solar desalination is a cost effective method to obtain potable water because of freely available clean and green energy source. In this paper, a transient mathematical model was developed for the multi-stage evacuated solar desalination system to achieve the optimum system configuration for the maximum year round performance and distillate yield. The effect of various design and operating parameters on the thermal characteristics and performance of the system were analyzed. It was found that an optimum configuration of four stages with 100mm gap between them when supplied with a mass flow rate of 55kg/m2/day would result in best performance throughout the year. The maximum and minimum yields of 28.044 kg/m2/day and 13.335 kg/m2/day for fresh water at a distillate efficiency of 50.989% and 24.245% and overall thermal efficiency of 81.171% and 40.362% are found in the months of March and December respectively owing to the climatic conditions. The yield decreases to 18.614 kg/m2/day and 9.791 kg/m2/day for brine solution at a distillate efficiency of 33.844% and 17.802% and overall thermal efficiency of 53.876% and 29.635% for March and December respectively The maximum yield of 53.211 kg/m2/day is found in March at an operating pressure of 0.03 bar. The multi-stage evacuated solar desalination system is economically viable and can meet the needs of rural and urban communities to necessitate 10 to 30 kg per day of fresh water.

  2. iGC2: an architecture for micro gas chromatographs utilizing integrated bi-directional pumps and multi-stage preconcentrators

    International Nuclear Information System (INIS)

    This paper reports an integrated micro gas chromatography (µGC) architecture which utilizes a bi-directional micropump. Four integral components-–the bi-directional Knudsen pump (KP2), a two-stage preconcentrator-focuser (PCF2), a separation column, and a gas detector-–are integrated in a 4.3 cm3 stack, forming a serial flow path. All four components are fabricated using the same three-mask process. Compared to the conventional approach used with multi-stage preconcentrators, in which valves are used to reverse flow between the sampling phase and the separation phase, this µGC architecture reduces the overall complexity. In this architecture, the vapors being sampled are drawn through the detector and column before reaching the PCF2. The microsystem operation is experimentally validated by quantitative analyses of benzene, toluene, and xylene vapors ranging in concentration from 43–1167 mg m−3. (paper)

  3. Multi-stage thermal-economical optimization of compact heat exchangers: A new evolutionary-based design approach for real-world problems

    International Nuclear Information System (INIS)

    The complicated task of design optimization of compact heat exchangers (CHEs) have been effectively performed by using evolutionary algorithms (EAs) in the recent years. However, mainly due to difficulties of handling extra variables, the design approach has been based on constant rates of heat duty in the available literature. In this paper, a new design strategy is presented where variable operating conditions, which better represent real-world problems, are considered. The proposed strategy is illustrated using a case study for design of a plate-fin heat exchanger though it can be employed for all types of heat exchangers without much change. Learning automata based particle swarm optimization (LAPSO), is employed for handling nine design variables while satisfying various equality and inequality constraints. For handling the constraints, a novel feasibility based ranking strategy (FBRS) is introduced. The numerical results indicate that the design based on variable heat duties yields in more cost savings and superior thermodynamics efficiency comparing to a conventional design approach. Furthermore, the proposed algorithm has shown a superior performance in finding the near-optimum solution for this task when it is compared to the most popular evolutionary algorithms in engineering applications, i.e. genetic algorithm (GA) and particle swarm optimization (PSO). - Highlights: • Multi-stage design of heat exchangers is presented. • Feasibility based ranking strategy is employed for constraint handling. • Learning abilities added to particle swarm optimization

  4. Reprocessing and partitioning for recycle transmutation to perform geologic disposal by using counter-current, multi-stage, centrifugal extraction process

    International Nuclear Information System (INIS)

    P and T treatment of MA (Minor Actinides) and LLFP (Low level fission products) in HLW (High level wastes) has a role to avoid the unanticipated uncertainty, which might be accompanied by geologic disposal in a super-long period, caused by the change of geologic behavior and/or geologic environment. R and P (reprocessing and partitioning) process should be improved even now for multi-recycling of U and Pu, MA and LLFP for P and T treatment with low inventory. Six-group partitioning based on five criteria for partitioning was studied to make up the concept of zero-release GSC (glass solidified canister), in which MA and LLFP are eliminated by P and T treatment. Drastic number reduction of GSC is another significant role gained by P and T treatment, in order to save the total cost of current geologic disposal and compensate the cost required by P and T treatment. In order to examine the possibility of multi-cycled R and P system for transmutation of MA and LLFP, a compact, counter-current, multi-stage centrifugal extractor and a similar con-current semi-continuous centrifugal separator were studied to get the concept of sharp cut-off extractor and a semi-continuous precipitator, for treating MA, ST and SL (Stable and short-lived nuclides) and LLFP in HLW. (author)

  5. Dynamic performance of cable-stayed bridge tower with multi-stage pendulum mass damper under wind excitations--Ⅱ:Experiment

    Institute of Scientific and Technical Information of China (English)

    Guo Anxin; Y L Xu; Li Hui

    2007-01-01

    The possibility of using a multi-stage pendulum mass damper(MSPMD) to control wind-induced vibration of a single column tower of a cable-stayed bridge during construction was studied theoretically in part Ⅰ of this work.In this paper,the performance of the MSPMD for reducing bridge tower vibration is studied experimentally.A MSPMD model and a tower model of the bridge with geometry scaling of 1:100 were designed and manufactured.Calibration of the MSPMD model with different wire lengths is conducted to verify the analytical model of the damper.A series of tests for the uncontrolled freestanding tower,tower with cables,and tower with MSPMD model are then performed under harmonic and white noise excitations.The experimental results show that the responses of the tower model significantly decrease with the installation of the MSPMD model,which demonstrates the effectiveness of the MSPMD to mitigate the vibration of the bridge tower.

  6. Loss of p19(Arf facilitates the angiogenic switch and tumor initiation in a multi-stage cancer model via p53-dependent and independent mechanisms.

    Directory of Open Access Journals (Sweden)

    Danielle B Ulanet

    Full Text Available The Arf tumor suppressor acts as a sensor of oncogenic signals, countering aberrant proliferation in large part via activation of the p53 transcriptional program, though a number of p53-independent functions have been described. Mounting evidence suggests that, in addition to promoting tumorigenesis via disruptions in the homeostatic balance between cell proliferation and apoptosis of overt cancer cells, genetic alterations leading to tumor suppressor loss of function or oncogene gain of function can also incite tumor development via effects on the tumor microenvironment. In a transgenic mouse model of multi-stage pancreatic neuroendocrine carcinogenesis (PNET driven by inhibition of the canonical p53 and Rb tumor suppressors with SV40 large T-antigen (Tag, stochastic progression to tumors is limited in part by a requirement for initiation of an angiogenic switch. Despite inhibition of p53 by Tag in this mouse PNET model, concomitant disruption of Arf via genetic knockout resulted in a significantly accelerated pathway to tumor formation that was surprisingly not driven by alterations in tumor cell proliferation or apoptosis, but rather via earlier activation of the angiogenic switch. In the setting of a constitutional p53 gene knockout, loss of Arf also accelerated tumor development, albeit to a lesser degree. These findings demonstrate that Arf loss of function can promote tumorigenesis via facilitating angiogenesis, at least in part, through p53-independent mechanisms.

  7. A multi-stage approach to maximizing geocoding success in a large population-based cohort study through automated and interactive processes

    Directory of Open Access Journals (Sweden)

    Jennifer S. Sonderman

    2012-05-01

    Full Text Available To enable spatial analyses within a large, prospective cohort study of nearly 86,000 adults enrolled in a 12-state area in the southeastern United States of America from 2002-2009, a multi-stage geocoding protocol was developed to efficiently maximize the proportion of participants assigned an address level geographic coordinate. Addresses were parsed, cleaned and standardized before applying a combination of automated and interactive geocoding tools. Our full protocol increased the non-Post Office (PO Box match rate from 74.5% to 97.6%. Overall, we geocoded 99.96% of participant addresses, with only 5.2% at the ZIP code centroid level (2.8% PO Box and 2.3% non-PO Box addresses. One key to reducing the need for interactive geocoding was the use of multiple base maps. Still, addresses in areas with population density 920 persons/km2 (odds ratio (OR = 5.24; 95% confidence interval (CI = 4.23, 6.49, as were addresses collected from participants during in-person interviews compared with mailed questionnaires (OR = 1.83; 95% CI = 1.59, 2.11. This study demonstrates that population density and address ascertainment method can influence automated geocoding results and that high success in address level geocoding is achievable for large-scale studies covering wide geographical areas.

  8. Cu deficiency in multi-stage co-evaporated Cu(In,Ga)Se{sub 2} for solar cells applications: Microstructure and Ga in-depth alloying

    Energy Technology Data Exchange (ETDEWEB)

    Caballero, R., E-mail: raquel.caballero@helmholtz-berlin.de [Helmholtz Zentrum Berlin fuer Materialien und Energie, Hahn-Meitner Platz 1, 14109 Berlin (Germany); Izquierdo-Roca, V. [M-2E/XaRMAE/IN2UB, Departament d' Electronica, Universitat de Barcelona, C. Marti i Franques 1, 08028 Barcelona (Spain); Fontane, X. [IREC, Catalonia Institute for Energy Research, C. Joseph Pla 2 B2, 08019 Barcelona (Spain); Kaufmann, C.A. [Helmholtz Zentrum Berlin fuer Materialien und Energie, Hahn-Meitner Platz 1, 14109 Berlin (Germany); Alvarez-Garcia, J. [Centre de Recerca i Investigacio de Catalunya (CRIC), Trav. de Gracia 108, 08012 Barcelona (Spain); Eicke, A. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung, Industriestrasse 6, 70565 Stuttgart (Germany); Calvo-Barrio, L. [Lab. Analisis de Superficies, SCT, Universitat de Barcelona, Lluis Sole i Sabaris 1-3, 08028 Barcelona (Spain); Perez-Rodriguez, A. [M-2E/XaRMAE/IN2UB, Departament d' Electronica, Universitat de Barcelona, C. Marti i Franques 1, 08028 Barcelona (Spain)] [IREC, Catalonia Institute for Energy Research, C. Joseph Pla 2 B2, 08019 Barcelona (Spain); Schock, H.W. [Helmholtz Zentrum Berlin fuer Materialien und Energie, Hahn-Meitner Platz 1, 14109 Berlin (Germany); Morante, J.R. [M-2E/XaRMAE/IN2UB, Departament d' Electronica, Universitat de Barcelona, C. Marti i Franques 1, 08028 Barcelona (Spain)] [IREC, Catalonia Institute for Energy Research, C. Joseph Pla 2 B2, 08019 Barcelona (Spain)

    2010-05-15

    The objective of this work is to study the influence of the maximum Cu content during the deposition of Cu(In,Ga)Se{sub 2} (CIGSe) by multi-stage co-evaporation on the phases present in the final film, the film structure and the electrical properties of resulting solar cell devices. The variation of the composition is controlled by the Cu content in stage 2 of the deposition process. The different phases are identified by Raman spectroscopy. The in-depth Ga gradient distribution is investigated by in-depth resolved Raman scattering and secondary neutral mass spectroscopy. The morphology of the devices is studied by scanning electron microscopy. Efficiencies of 9.2% are obtained for ordered-vacancy-compound-based cells with a Cu/(In + Ga) ratio = 0.35, showing the system's flexibility. This work supports the current growth model: a small amount of Cu excess during the absorber process is required to obtain a quality microstructure and high performance devices.

  9. Synthetic TLR4 agonists enhance functional antibodies and CD4+ T-cell responses against the Plasmodium falciparum GMZ2.6C multi-stage vaccine antigen.

    Science.gov (United States)

    Baldwin, Susan L; Roeffen, Will; Singh, Susheel K; Tiendrebeogo, Regis W; Christiansen, Michael; Beebe, Elyse; Carter, Darrick; Fox, Christopher B; Howard, Randall F; Reed, Steven G; Sauerwein, Robert; Theisen, Michael

    2016-04-27

    A subunit vaccine targeting both transmission and pathogenic asexual blood stages of Plasmodium falciparum, i.e., a multi-stage vaccine, could be a powerful tool to combat malaria. Here, we report production and characterization of the recombinant protein GMZ2.6C, which contains a fragment of the sexual-stage protein Pfs48/45-6C genetically fused to GMZ2, an asexual vaccine antigen in advanced clinical development. To select the most suitable vaccine formulation for downstream clinical studies, GMZ2.6C was tested with various immune modulators in different adjuvant formulations (stable emulsions, liposomes, and alum) in C57BL/6 mice. Some, but not all, formulations containing either the synthetic TLR4 agonist GLA or SLA elicited the highest parasite-specific antibody titers, the greatest IFN-γ responses in CD4+ TH1 cells, and the highest percentage of multifunctional CD4+ T cells expressing IFN-γ and TNF in response to GMZ2.6C. Both of these agonists have good safety records in humans. PMID:26994314

  10. A Multi-stage Carcinogenesis Model to Investigate Caloric Restriction as a Potential Tool for Post-irradiation Mitigation of Cancer Risk

    Science.gov (United States)

    Tani, Shusuke; Blyth, Benjamin John; Shang, Yi; Morioka, Takamitsu; Kakinuma, Shizuko; Shimada, Yoshiya

    2016-01-01

    The risk of radiation-induced cancer adds to anxiety in low-dose exposed populations. Safe and effective lifestyle changes which can help mitigate excess cancer risk might provide exposed individuals the opportunity to pro-actively reduce their cancer risk, and improve mental health and well-being. Here, we applied a mathematical multi-stage carcinogenesis model to the mouse lifespan data using adult-onset caloric restriction following irradiation in early life. We re-evaluated autopsy records with a veterinary pathologist to determine which tumors were the probable causes of death in order to calculate age-specific mortality. The model revealed that in both irradiated and unirradiated mice, caloric restriction reduced the age-specific mortality of all solid tumors and hepatocellular carcinomas across most of the lifespan, with the mortality rate dependent more on age owing to an increase in the number of predicted rate-limiting steps. Conversely, irradiation did not significantly alter the number of steps, but did increase the overall transition rate between the steps. We show that the extent of the protective effect of caloric restriction is independent of the induction of cancer from radiation exposure, and discuss future avenues of research to explore the utility of caloric restriction as an example of a potential post-irradiation mitigation strategy. PMID:27390741

  11. Advanced liquefaction using coal swelling and catalyst dispersion techniques

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, C.W. (Auburn Univ., AL (United States)); Gutterman, C. (Foster Wheeler Development Corp., Livingston, NJ (United States)); Chander, S. (Pennsylvania State Univ., University Park, PA (United States))

    1992-08-26

    Research in this project centers upon developing a new approach to the direct liquefaction of coal to produce an all-distillate product slate at a sizable cost reduction over current technology. The approach integrates all aspects of the coal liquefaction process including coal selection, pretreatment, coal swelling with catalyst impregnation, coal liquefaction experimentation, product recovery with characterization, alternate bottoms processing, and a technical assessment including an economic evaluation. The project is being carried out under contract to the United States Department of Energy. On May 28, 1992, the Department of Energy authorized starting the experimental aspects of this projects; therefore, experimentation at Amoco started late in this quarterly report period. Research contracts with Auburn University, Pennsylvania State University, and Foster Wheeler Development Corporation were signed during June, 1992, so their work was just getting underway. Their work will be summarized in future quarterly reports. A set of coal samples were sent to Hazen Research for beneficiation. The samples were received and have been analyzed. The literature search covering coal swelling has been up-dated, and preliminary coal swelling experiments were carried out. Further swelling experimentation is underway. An up-date of the literature on the liquefaction of coal using dispersed catalysts is nearing completion; it will be included in the next quarterly report.

  12. STUDY OF SOLVENT AND CATALYST INTERACTIONS IN DIRECT COAL LIQUEFACTION

    Energy Technology Data Exchange (ETDEWEB)

    Michael T. Klein

    2000-01-01

    Using a reactor in which the coal is physically separated from the solid catalyst by a porous wall permeable to the hydrogen donor solvent, it was shown that direct contact between the catalyst and the coal is not required for catalyzed coal liquefaction. This occurs however only when there is a hydrogen atmosphere, as liquefaction with catalyst participation does not occur in a nitrogen atmosphere. Liquefaction by hydrogen transfer from the donor solvent itself does occur. This suggests that there is transfer of hydrogen from the catalyst to the coal via the solvent. The character of the solvent makes a significant difference, the better solvents being good hydrogen donors. These results indicate that the role of the catalyst may be to regenerate the spent hydrogen donor solvent during the liquefaction process. The peak temperature for volatiles evolution has been shown to be a reproducible measure of the coal rank. This was shown by an excellent correlation (R2 = 0.998) between peak volatiles temperatures (by TGA) and vitrinite reflectance. Using TG/MS, the volatiles contents of coals of a wide range of ranks was determined. The low rank coals emit largely phenols and some other oxygen compounds and olefins. The higher rank coals emit largely aromatic hydrocarbons and some olefins.

  13. Liquefaction of lignocellulose: Do basic and acidic additives help out?

    NARCIS (Netherlands)

    Kumar, S.; Lange, J.P.; Rossum, van G.; Kersten, S.R.A.

    2015-01-01

    Lignocellulosic feedstock can be converted to bio-oil by direct liquefaction in a phenolic solvent such as guaiacol. The bio-oil could then be further upgraded to transportation fuel using conventional oil refining process. The production of heavy components (molecular weight >1000 Da) was found to

  14. 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...

  15. Fine particle clay catalysts for coal liquefaction. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Olson, E.S.

    1995-08-01

    In an effort to develop new disposable catalysts for direct coal liquefaction, several types of clay-supported pyrrhotite catalysts were prepared and tested. These included iron-pillared montmorillonite, mixed iron/alumina-pillared montmorillonite, iron-impregnated montmorillonite, and iron oxometallate-impregnated montmorillonite.

  16. 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

  17. 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)

  18. The latest developments and outlook for hydrogen liquefaction technology

    Energy Technology Data Exchange (ETDEWEB)

    Ohlig, K.; Decker, L. [Linde Kryotechnik AG, Pfungen, CH-8422 (Switzerland)

    2014-01-29

    Liquefied hydrogen is presently mainly used for space applications and the semiconductor industry. While clean energy applications, for e.g. the automotive sector, currently contribute to this demand with a small share only, their demand may see a significant boost in the next years with the need for large scale liquefaction plants exceeding the current plant sizes by far. Hydrogen liquefaction for small scale plants with a maximum capacity of 3 tons per day (tpd) is accomplished with a Brayton refrigeration cycle using helium as refrigerant. This technology is characterized by low investment costs but lower process efficiency and hence higher operating costs. For larger plants, a hydrogen Claude cycle is used, characterized by higher investment but lower operating costs. However, liquefaction plants meeting the potentially high demand in the clean energy sector will need further optimization with regard to energy efficiency and hence operating costs. The present paper gives an overview of the currently applied technologies, including their thermodynamic and technical background. Areas of improvement are identified to derive process concepts for future large scale hydrogen liquefaction plants meeting the needs of clean energy applications with optimized energy efficiency and hence minimized operating costs. Compared to studies in this field, this paper focuses on application of new technology and innovative concepts which are either readily available or will require short qualification procedures. They will hence allow implementation in plants in the close future.

  19. 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.

  20. 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.

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

    International Nuclear Information System (INIS)

    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

  2. FEM simulations of a multi stage forming process on Sandvik maraging steel 1RK91 describing the stress assisted and the strain induced martensite transformation

    Science.gov (United States)

    Post, J.; Huétink, J.; Geijselaers, H. J. M.; Voncken, R. M. J.

    2003-10-01

    Sandvik steel IRK91 combines good corrosion resistance with high strength. The steel has good deformability in austenitic conditions. This material belongs to the group of metastable austenites, so during deformation a strain-induced transformation into martensite takes place. After deformation, transformation ccontinues as a resuit of internai stresses. Depending on the heat treatment, this stress-assisted transformation is more or less atitocatalytic. Both transformations are stress-state and temperature dependent. This article presents a constitutive model for this steel, based on the macroscopic material behaviour measured by inductive measurements. Both the stress-assisted and the strain-induced transformation to martensite are incorpomted in this model. Path-dependent work hardening is also taken into account. The model is implemented in the commercial FEM code MARC for doing simulations. In the simulations thé tools are treated as rigid bodies, friction is taken into account beeause it inflnences the stress state during metal forming. The material properties after a calculation step are mapped to the next step to incorporate the cumulative effect of the transformation and work hardening during the different steps. A multi-stage metal-forming process is simulated. The process consists of different forming steps with intervals between them to simulate the waiting time between the different metal-forming steps. Results of the transformation behaviour are presented together with the shape of the product during and after metal forming. Finally, this article shows the results of the calculation in which the material transforms autocatalytic, as a resuit of a specific heat treatment.

  3. Restoration of eroded stratal thickness in key periods of tectonic change in a multi-stage superimposed Tarim Basin in China

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    With an area of 56×104km2, the Tarim Basin is the largest inland basin in China and is also generally acknowledged as one of the most important areas for potential oil and gas exploration. On the basis of data from 22 regional seismic profiles and 40 drilling wells, 15 important first-order and second-order regional unconformities were defined.Almost all the main unconformities are superimposed unconfomities. Since the Cambrian, 5 key periods of tectonic change have occurred during the evolution of the Tarim Basin. The total eroded stratal thickness of the above-mentioned unconformities was calculated by using the method of virtual extrapolation of seismic reflection. The results indicate that the total eroded stratal thickness of different periods is quite different in different locations of the basin. Taking the Upper-Middle Ordovician as an example, its thickness restoration of eroded strata was calculated into individual stages i.e. its thickness restoration of eroded strata was calculated to different tectonic periods. Otherwise, as for the specific period of tectonic change, the underlying strata were, respectively eroded and thus the thickness restoration of eroded strata was calculated into individual intervals. Taking the Early Hercynian period as an example, the eroded stratal thickness was calculated into individual intervals to calculate the ratio of intervals of various ages occupying the total eroded thickness. The results show that for the same stratum, its degree of erosion is quite different in different periods and at different locations, due to the varying influence of tectonic movement. The unconformities of some key periods of tectonic change have different controls on the degree of erosion and the eroded range of the individual period of the underlying strata which are the typical characteristics of multi-stage superimposition of unconformities in the Tarim Basin.

  4. Sustainable conversion of coffee and other crop wastes to biofuels and bioproducts using coupled biochemical and thermochemical processes in a multi-stage biorefinery concept.

    Science.gov (United States)

    Hughes, Stephen R; López-Núñez, Juan Carlos; Jones, Marjorie A; Moser, Bryan R; Cox, Elby J; Lindquist, Mitch; Galindo-Leva, Luz Angela; Riaño-Herrera, Néstor M; Rodriguez-Valencia, Nelson; Gast, Fernando; Cedeño, David L; Tasaki, Ken; Brown, Robert C; Darzins, Al; Brunner, Lane

    2014-10-01

    The environmental impact of agricultural waste from the processing of food and feed crops is an increasing concern worldwide. Concerted efforts are underway to develop sustainable practices for the disposal of residues from the processing of such crops as coffee, sugarcane, or corn. Coffee is crucial to the economies of many countries because its cultivation, processing, trading, and marketing provide employment for millions of people. In coffee-producing countries, improved technology for treatment of the significant amounts of coffee waste is critical to prevent ecological damage. This mini-review discusses a multi-stage biorefinery concept with the potential to convert waste produced at crop processing operations, such as coffee pulping stations, to valuable biofuels and bioproducts using biochemical and thermochemical conversion technologies. The initial bioconversion stage uses a mutant Kluyveromyces marxianus yeast strain to produce bioethanol from sugars. The resulting sugar-depleted solids (mostly protein) can be used in a second stage by the oleaginous yeast Yarrowia lipolytica to produce bio-based ammonia for fertilizer and are further degraded by Y. lipolytica proteases to peptides and free amino acids for animal feed. The lignocellulosic fraction can be ground and treated to release sugars for fermentation in a third stage by a recombinant cellulosic Saccharomyces cerevisiae, which can also be engineered to express valuable peptide products. The residual protein and lignin solids can be jet cooked and passed to a fourth-stage fermenter where Rhodotorula glutinis converts methane into isoprenoid intermediates. The residues can be combined and transferred into pyrocracking and hydroformylation reactions to convert ammonia, protein, isoprenes, lignins, and oils into renewable gas. Any remaining waste can be thermoconverted to biochar as a humus soil enhancer. The integration of multiple technologies for treatment of coffee waste has the potential to

  5. Multi-Stage Mass Spectrometry Analysis of Sugar-Conjugated β-Turn Structures to be Used as Probes in Autoimmune Diseases

    Science.gov (United States)

    Giangrande, Chiara; Auberger, Nicolas; Rentier, Cédric; Papini, Anna Maria; Mallet, Jean-Maurice; Lavielle, Solange; Vinh, Joëlle

    2016-04-01

    Synthetic sugar-modified peptides were identified as antigenic probes in the context of autoimmune diseases. The aim of this work is to provide a mechanistic study on the fragmentation of different glycosylated analogs of a synthetic antigenic probe able to detect antibodies in a subpopulation of multiple sclerosis patients. In particular the N-glucosylated type I' β-turn peptide structure called CSF114(Glc) was used as a model to find signature fragmentations exploring the potential of multi-stage mass spectrometry by MALDI-LTQ Orbitrap. Here we compare the fragmentation of the glucosylated form of the synthetic peptide CSF114(Glc), bearing a glucose moiety on an asparagine residue, with less or non- immunoreactive forms, bearing different sugar-modifications, such as CSF114(GlcNAc), modified with a residue of N-acetylglucosamine, and CSF114[Lys7(1-deoxyfructopyranosyl)], this last one modified with a 1-deoxyfructopyranosyl moiety on a lysine at position 7. The analysis was set up using a synthetic compound specifically deuterated on the C-1 to compare its fragmentation with the fragmentation of the undeuterated form, and thus ascertain with confidence the presence on an Asn(Glc) within a peptide sequence. At the end of the study, our analysis led to the identification of signature neutral losses inside the sugar moieties to characterize the different types of glycosylation/glycation. The interest of this study lies in the possibility of applyimg this approach to the discovery of biomarkers and in the diagnosis of autoimmune diseases.

  6. Multi-stage Virtual Over-sample Digital Hystersis Control%分段式虚拟过采样数字滞环控制

    Institute of Scientific and Technical Information of China (English)

    胡义华; 邓焰; 刘全伟; 陶勇

    2012-01-01

    The grid-connected current control is one of important controls in distributed generation systems. Based on the traditional hysteresis control, a multi-stage over-sample digital hysteresis control was developed which can bring down the MOSFET frequency and the output current total harmonic distortion (THD). Meanwhile, the invalidation of hysteresis bandwidth was overcome by virtual over-sample control method. A simulation model was built to proof the proposed control method, and comparative analysis was also studied among hysteresis controls. A prototype was set up, and the experimental results verified the correction of the proposed system correction.%并网电流控制是分布式发电系统中的技术难点.在分析传统滞环控制策略的基础上,针对不对称多电平拓扑研究了一种分段式虚拟过采样并网滞环控制策略.通过将母线电压按正弦波形分段的方法,可以有效分配开关管开关频率,降低输出电流的谐波含量.在真实采样点之间插入虚拟采样点的虚拟过采样方法,解决了滞环控制中环宽失效问题.利用仿真软件对多种滞环控制策略进行对比分析,搭建实验平台对提出的算法进行实验验证.仿真与实验结果都验证了所提控制算法的正确性.

  7. Liquefaction hazard potential in north eastern united arab emirates

    Science.gov (United States)

    Al-Homoud, A.

    2003-04-01

    The United Arab Emirates is adjacent to the Iranian plateau characterized by very high density of active and recent faults. The Iranian plateau is one of the seismically active areas of the world and frequently suffers destructive and catastrophic earthquakes that cause heavy loss of human life and widespread damage. Therefore seismic risk in the North Eastern UAE (Sharjah and Dubai) is due to the neighboring very active Iranian seismotectonic province. As almost all foundation soils in the UAE are cohesionless material, which is clearly identified as recent fill deposits in major industrial and residential areas, and given the rapid on-shore infrastructure developments in the North Eastern UAE, and due to the lack of geo-hazards maps, it is considered vital to develop liquefaction hazard maps for these areas. The earthquake risk was brought to the attention of the public and the government upon the recent March 11, 2002 earthquake of magnitude 5.1 on Richter Scale that struck the northern emirates and caused slight damages. Initial seismic hazard assessment studies showed that Design Horizontal Peak Ground Accelerations (PGA) in Sharjah and Dubai with 90% probabilities of non-exceedence in 50 years is around 200 cm/sec^2. This study is concerned with the development of liquefaction hazard maps in North Eastern Emirates UAE Cities of Sharjah and Dubai. Liquefaction hazard potential for various soil deposits in these cities is evaluated for different Peak Ground Acceleation Values. Data from thorough geotechnical studies were evaluated. This include boreholes drilling (with SPT tests) and shear strength for representative sand samples taken from several boreholes and at different depths. Liquefaction hazard potential is evaluated at representative sites in the city of Dubai and Sharjah using the state of the art liquefaction potential evaluation methods (e.g. Seed's cyclic stress ratio approach). Results indicate clearly that the coastal areas have a high potential

  8. EDS coal liquefaction process development: Phase V. Final technical progress report, Volume I

    Energy Technology Data Exchange (ETDEWEB)

    None

    1984-02-01

    All objectives in the EDS Cooperative Agreement for Phases III-B through V have been achieved for the RCLU pilot plants. EDS operations have been successfully demonstrated in both the once-through and bottoms recycle modes for coals of rank ranging from bituminous to lignitic. An extensive data base detailing the effects of process variable changes on yields, conversions and product qualities for each coal has been established. Continuous bottoms recycle operations demonstrated increased overall conversion and improved product slate flexibility over once-through operations. The hydrodynamics of the liquefaction reactor in RCLU were characterized through tests using radioactive tracers in the gas and slurry phases. RCLU was shown to have longer liquid residence times than ECLP. Support work during ECLP operations contributed to resolving differences between ECLP conversions and product yields and those of the small pilot plants. Solvent hydrogenation studies during Phases IIIB-V of the EDS program focused on long term activity maintenance of the Ni-MO-10 catalyst. Process variable studies for solvents from various coals (bituminous, subbituminous, and lignitic), catalyst screening evaluations, and support of ECLP solvent hydrogenation operations. Product quality studies indicate that highly cyclic EDS naphthas represent unique and outstanding catalytic reforming feedstocks. High volumes of high octane motor gasoline blendstock are produced while liberating a considerable quantity of high purity hydrogen.

  9. Chemistry and morphology of coal liquefaction. Annual report, October 1, 1979-September 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Heinemann, H.

    1980-09-01

    The present annual report summarizes quarterly reports and includes work performed during the last quarter of fiscal 1980. The first year of this project has just been completed and much of the time and effort has been concentrated on equipment building, assembling, testing, and on staffing. This, of course, has been more true in the areas of work with spectroscopic and high pressure equipment than in organic chemical reactions. More experimental results are therefore reported in the areas of hydrogen transfer mechanisms and catalysis and organo-metallic chemistry. A few of the significant results in these and other areas are the evidence for catalysis in hydrogen transfer from tetralin; a novel and possibly very important new synthesis of alkyl aromatics from benzene, carbon monoxide, and hydrogen; the study of coals in the transmission electron microscope identifying coal macerals, minerals and metals, and leading to the possibility of observing location of and catalytic influences on pyrolysis and hydrogenation at elevated temperatures; the finding that scales formed on deactivated cobalt-molybdena-alumina-hydrogenation catalysts contain not only metals from the liquid feedstocks, but also molybdenum sulfide which must derive from migration from the catalyst interior to and beyond the surface. Insights gained in mechanisms of pyrolysis, hydrogenation, hydrogen transfer, and indirect liquefaction of coal promise to lead to improving technology by defining problem areas and showing routes to by-pass problems.

  10. Chemistry and morphology of coal liquefaction. Quarterly report, January 1, 1984-March 31, 1984

    Energy Technology Data Exchange (ETDEWEB)

    Heinemann, H.

    1984-04-01

    In task 1, selective synthesis of gasoline-range components from synthesis gas, rate expressions were developed for four different iron catalysts (promoted and unpromoted). Data for all four catalysts can be correlated by a semi-empirical expression. In task 2 catalyzed low temperature reactions of carbon and water, the catalytic activity for the production of hydrocarbons from graphite and water over KOH plus a co-catalyst was investigated for several first row transition metals. NiO showed the greatest activity. Several samples of /sup 13/CO, /sup 13/CO/sub 2/ and H/sub 2/O adsorbed on graphite and on catalyst-graphite systems after reaction with steam were prepared for NMR investigation. In task 3 chemistry of coal solubilization and liquefaction, rate studies of quinoline reduction to tetrahydroquinoline in the presence of the homogeneous catalysts (phi/sub 3/P)/sub 3/RhCl have provided definitive evidence that benzothiophene, indole, pyrrole, carbazole, thiophene, p-cresol and dibenzothiophene enhance the initial rate of hydrogenation of quinoline by a factor greater than 1.5. P-cresol was found to enhance the initial rate of hydrogenation of quinoline (1.6 to 2 fold) in a model coal liquid with polymer-supported (2% cross-linked) (phi/sub 3/P)/sub 3/ RhCl. 2 references, 6 figures.

  11. Evaluation of Liquefaction Return Period for Bangalore Based on Standard Penetration Test Data: Performance Based Approach

    Directory of Open Access Journals (Sweden)

    K. S. Vipin

    2009-01-01

    Full Text Available Problem statement: The conventional liquefaction evaluation is based on a deterministic approach. However in this method the uncertainty in the earthquake loading is not properly taken into account. However recent research in this field indicates that this uncertainty in the earthquake loading has to be considered in the liquefaction potential evaluation. Moreover the evaluation of liquefaction return period is not possible in the conventional deterministic methods. This study explained the methods for evaluating the probability of liquefaction and the return period of liquefaction based on probabilistic approach. Approach: In this study the geotechnical data was collected from 450 bore holes in Bangalore, India, covering an area of 220 km2. The seismic hazard analysis for the study area is carried out using Probabilistic Seismic Hazard Analysis (PSHA and the peak acceleration at ground surface was evaluated for site class-D after considering local site effects. For assessment of site class, shear wave velocity profiles in the city had been obtained using Multichannel Analysis of Surface Waves (MASW survey. Based on this data the probabilistic liquefaction analysis was done to evaluate the probability of liquefaction in the study area. Based on the performance based approach the liquefaction return period for the study area was also evaluated. Results: The results showed the variation of liquefaction susceptibility for the study area. The corrected standard penetration values required to prevent the liquefaction for return periods of 475 and 2500 years were also presented here. Conclusion/Recommendations: The spatial variation of probability of liquefaction and the factor of safety against liquefaction evaluated using the two methods match well for the study area.

  12. Evaluation of Liquefaction Return Period for Bangalore Based on Standard Penetration Test Data: Performance Based Approach

    OpenAIRE

    Vipin, K. S.; Sitharam, T. G.

    2009-01-01

    Problem statement: The conventional liquefaction evaluation is based on a deterministic approach. However in this method the uncertainty in the earthquake loading is not properly taken into account. However recent research in this field indicates that this uncertainty in the earthquake loading has to be considered in the liquefaction potential evaluation. Moreover the evaluation of liquefaction return period is not possible in the conventional deterministic methods. This study explained the m...

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

    International Nuclear Information System (INIS)

    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)

  14. 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.

  15. Engineering of Ground for Liquefaction Mitigation Using Granular Columnar Inclusions: Recent Developments

    Directory of Open Access Journals (Sweden)

    A. M. Krishna

    2009-01-01

    Full Text Available Problem statement: Liquefaction was the most hazardous damage during an earthquake. Ground improvement techniques were employed to mitigate liquefaction hazards. Most common methods to improve engineering properties of soils are densification, reinforcement, grouting/mixing and drainage. Among various remedial measures available, installation of columnar granular inclusions is the most widely adopted method for liquefaction mitigation. Approach: Columnar granular inclusions function as drains and permit rapid dissipation of earthquake induced pore pressures by virtue of their high permeability. Results: One of the chief benefits of ground treatment with granular piles is the densification of in situ ground by which the in-situ properties of the ground get modified to mitigate liquefaction potential. Further, the very high deformation modulus and stiffness of the granular pile material provide reinforcement for the in situ soil and offer another mechanism to mitigate liquefaction. The study described briefly the phenomenon of liquefaction and the associated features. A short discussion on various ground improvement methods available for liquefaction mitigation was presented highlighting the importance of columnar inclusions. Construction methods of different granular columnar inclusions like sand compaction piles/ granular piles were discussed briefly. Recent developments in the research of columnar granular inclusions as liquefaction counter measures were presented in relation to physical, numerical and analytical model studies. Conclusion/Recommendations: Columnar granular inclusions were demonstrated to be very effective for liquefaction mitigation in different case studies and research investigations.

  16. Liquefaction Susceptibility of Soils With Clay Particles from Earthquake-induced Landslides

    Institute of Scientific and Technical Information of China (English)

    CHEN Chuan-sheng; JIANG Xin; ZHANG Xu

    2007-01-01

    The main reason for earthquake-induced landslides is liquefaction of soil, a process considered to occur mostly in sandy soils. Liquefaction can occur in clayey soils has also been reported and proven in the recent literature, but liquefaction in clayey soils still remains unclear and there are many questions that need to be addressed. In order to address these questions, an depth study on the liquefaction potential of clayey soils was conducted on the basis of field investigation and a series of laboratory tests on the samples collected from the sliding surface of the landslides. The liquefaction potential of the soils was studied by means of undrained cyclic ring-shear tests. Research results show that the liquefaction potential of sandy soils is higher than that of clayey soils given the same void ratio;the soil resistance to liquefaction rises with an increase in plasticity for clayey soils; relation between plasticity index and the liquefaction potential of soil can be used in practical application to estimate the liquefaction potential of soil.

  17. 进化计算在多阶段生产计划问题中的应用%The Application of Evolutionary Computation to Multi-stage Production Planning Problem

    Institute of Scientific and Technical Information of China (English)

    周根贵; 翁潇彬

    2001-01-01

    提出一种新的进化计算方法用以解决多阶段生产计划问题,数值计算表明该方法不仅对单目标的多阶段生产计划问题是有效的,而且,对多目标的多阶段生产计划问题也是有效的。%We propose a new evolutionary computation approach to deal with the multi-stage production planning problem. The numerical experiments show the effectiveness of the proposed method to the multi-stage production planning problems with both single objective and multiple objectives.

  18. An advanced extruder-feeder biomass liquefaction reactor system

    Science.gov (United States)

    White, Don H.; Wolf, D.; Davenport, G.; Mathews, S.; Porter, M.; Zhao, Y.

    1987-11-01

    A unique method of pumping concentrated, viscous biomass slurries that are characteristic of biomass direct liquefaction systems was developed. A modified single-screw extruder was shown to be capable of pumping solid slurries as high as 60 weight percent wood flour in wood oil derived vacuum bottoms, as compared to only 10 to 20 weight percent wood flour in wood oil in conventional systems. During the period August, 1985 to April, 1987, a total of 18 experimental continuous biomass liquefaction runs were made using white birch feedstock. Good operability with feed rates up to 30 lb/hr covering a range of carbon monoxide, sodium carbonate catalyst, pressures from 800 to 3000 psi and temperatures from 350 C to 430 C was achieved. Crude wood oils containing 6 to 10 weight percent residual oxygen were obtained. Other wood oil characteristics are reported.

  19. INVESTIGATION INTO NATURAL GAS LIQUEFACTION METHODS, LNG TRANSPORT AND STORAGE

    Directory of Open Access Journals (Sweden)

    Atakan AVCI

    1995-03-01

    Full Text Available Liquefied Natural Gas (LNG processes are very new in Turkey. The Government of Turkey, due to diversification of supply and balancing of seasonal load, decided to import LNG from Algeria. The first shipment in Marmara Ereğli import terminal has been carried out in the August the 3 rd, 1994. LNG after regasification will be injected into the main transmission pipeline. The share of LNG in the world natural gas trade was approixmately 22.1% in 1988. According to the forecast, LNG share will be rapidly spreading all over the world in near future. In this paper, treatment, liquefaction, transport, storage, regasification, distribution and utilisation of LNG are examined. Particular attention has given into liquefaction of natural gas.

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

    DEFF Research Database (Denmark)

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

    2006-01-01

    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......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.......6 sec, water depth = 42 cm, and the Shields parameter = 0.34-0.59. The experiments reveal that, with the introduction of waves, excess pore pressure builds up, which is followed by liquefaction during which internal waves are experienced at the interface of the water body and the liquefied sediment...

  1. Catalytic distillation structure

    Science.gov (United States)

    Smith, Jr., Lawrence A.

    1984-01-01

    Catalytic distillation structure for use in reaction distillation columns, a providing reaction sites and distillation structure and consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and being present with the catalyst component in an amount such that the catalytic distillation structure consist of at least 10 volume % open space.

  2. Catalytic combustor for hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Mercea, J.; Grecu, E.; Fodor, T.; Kreibik, S.

    1982-01-01

    The performance of catalytic combustors for hydrogen using platinum-supported catalysts is described. Catalytic plates of different sizes were constructed using fibrous and ceramic supports. The temperature distribution as well as the reaction efficiency as a function of the fuel input rate was determined, and a comparison between the performances of different plates is discussed.

  3. Mechanism of Liquefaction-Induced Large Settlements of Buildings

    OpenAIRE

    Zaheer Ahmed Almani; Kamran Ansari; Ashfaque Ahmed Memon

    2012-01-01

    In this paper, mechanism of liquefaction-related large settlements of the soil-structure system during the earthquake was studied using numerical modelling. The isolated shallow strip plane strain footing pad, supporting a typical simple frame structure, was founded on the ground at the shallow depth from the level ground surface. This system was modelled as plane-strain using the FLAC (Fast Lagrangian Analysis of continua) 2D dynamic modelling and analysis code. This case focuses...

  4. Hydrothermal liquefaction of Nannochloropsis oceanica in different solvents.

    Science.gov (United States)

    Caporgno, M P; Pruvost, J; Legrand, J; Lepine, O; Tazerout, M; Bengoa, C

    2016-08-01

    Although the hydrothermal liquefaction is considered a promising technology for converting microalgae into liquid biofuels, there are still some disadvantages. This paper demonstrated that the bio-oil yield can be significantly improved by adding alcohols as co-solvents and carrying out the conversion at mild conditions (microalgae (∼75% moisture) and alcohol concentrations which avoid both drying the microalgae and decreasing the amount of microalgae loaded in the reactor. PMID:27155795

  5. Mitigation of Liquefaction in Sandy Soils Using Stone Columns

    Science.gov (United States)

    Selcuk, Levent; Kayabalı, Kamil

    2010-05-01

    Soil liquefaction is one of the leading causes of earthquake-induced damage to structures. Soil improvement methods provide effective solutions to reduce the risk of soil liquefaction. Thus, soil ground treatments are applied using various techniques. However, except for a few ground treatment methods, they generally require a high cost and a lot of time. Especially in order to prevent the risk of soil liquefaction, stone columns conctructed by vibro-systems (vibro-compaction, vibro-replacement) are one of the traditional geotechnical methods. The construction of stone columns not only enhances the ability of clean sand to drain excess pore water during an earthquake, but also increases the relative density of the soil. Thus, this application prevents the development of the excess pore water pressure in sand during earthquakes and keeps the pore pressure ratio below a certain value. This paper presents the stone column methods used against soil liquefaction in detail. At this stage, (a) the performances of the stone columns were investigated in different spacing and diameters of columns during past earthquakes, (b) recent studies about design and field applications of stone columns were presented, and (c) a new design method considering the relative density of soil and the capacity of drenage of columns were explained in sandy soil. Furthermore, with this new method, earthquake performances of the stone columns constructed at different areas were investigated before the 1989 Loma Prieta and the 1994 Northbridge earthquakes, as case histories of field applications, and design charts were compiled for suitable spacing and diameters of stone columns with consideration to the different sandy soil parameters and earhquake conditions. Key Words: Soil improvement, stone column, excess pore water pressure

  6. Ground Improvement for Liquefaction Mitigation at Existing Highway Bridges

    OpenAIRE

    Cooke, Harry G.

    2000-01-01

    The feasibility of using ground improvement at existing highway bridges to mitigate the risk of earthquake-induced liquefaction damage has been studied. The factors and phenomena governing the performance of the improved ground were identified and clarified. Potential analytical methods for predicting the treated ground performance were investigated and tested. Key factors affecting improved ground performance are the type, size, and location of the treated ground. The improved groun...

  7. The influence of cementation on liquefaction resistance of sands

    OpenAIRE

    Iwabuchi, Jotaro

    1986-01-01

    Cohesionless sands are known to be susceptible to failure by liquefaction when they are saturated and subjected to earthquake shaking. Considerable study has been directed towards this subject over the past 20 years in recognition of the possibility of large-scale property damage or loss of life due to this type of failure. Recent evidence has shown that small degrees of cementation in a sand significantly reduce the likelihood of liquefication. However, the work to date has been ...

  8. Liquefaction of sunflower husks for biochar production / Nontembiso Piyo

    OpenAIRE

    Piyo, Nontembiso

    2014-01-01

    Biochar, a carbon-rich and a potential solid biofuel, is produced during the liquefaction of biomass. Biochar can be combusted for heat and power, gasified, activated for adsorption applications, or applied to soils as a soil amendment and carbon sequestration agent. It is very important and advantageous to produce biochar under controlled conditions so that most of the carbon is converted. The main objective of the study was to investigate the effect of solvents, reaction temp...

  9. 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 3,000 psi. By comparison, conventional pumping systems are capable of pumping slurries containing only 10--20 wt % wood flour in wood oil under similar conditions. The extruder-feeder has been integrated with a unique reactor 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 3,000 psi pressure reactor in the biomass liquefaction process. An experimental facility was constructed during 1983--84. Following shakedown operations, wood crude oil was produced by mid-1985. During the period January 1985 through 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 3,000 psi and temperatures from 350{degrees}C to 430{degrees}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. 43 refs., 81 figs., 52 tabs.

  10. 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.

  11. Development of computer simulator for coal liquefaction reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yawata, T.; Kobayashi, M.; Ohi, S.; Itho, H.; Hiraide, M. [Nippon Oil Co., Ltd., Tokyo (Japan)

    1995-12-31

    The computer simulator for a coal liquefaction reactor is a useful engineering tool to analyse the data of such reactors. The authors applied this technique to a reactor in the NEDOL process to predict the performance of the reactor, and to assist in the design of a reactor for demonstration plant. The development program of the simulator and its utilization plan are discussed. 4 figs., 2 tabs.

  12. Liquefaction Susceptibility in the Northern Provinces of Thailand

    Directory of Open Access Journals (Sweden)

    Supot Teachavorasinskun

    2009-01-01

    Full Text Available Problem statement: There are quite a few active faults recently found in the western and northern parts of Thailand, which could possibly induce earthquakes of magnitude (ML of 5.5-6.5. Although seismic design code has been enforced in the area since 1980, the fundamental knowledge on dynamic soil behavior has not been extensively attained. Approach: Collection of existing borehole information in the targeted areas to form a typical subsoil profile. This borehole information, together with analytical result obtained from logistic regression based on worldwide liquefaction database was used to conduct an effective stress analysis. Result: Literature reviews of the existing boreholes from the two largest provinces in the north, Chiang-Mai and Chiang-Rai, revealed that the areas were underlain by layers of loose to medium dense sand found at shallow depths. The corrected SPT N-value of those sand layers varies in the range of 5-20. A simple tool correlating the liquefaction probability, which correlated excess pore water pressure and peak ground acceleration, was proposed for the studied areas. Conclusion: The proposed correlation provided preliminary tool to evaluate risk of the shallow foundation from partial liquefaction in the two northern provinces of Thailand.

  13. 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.

  14. 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.

  15. Catalytic hydrocracking of primary maceral concentrate extracts prepared in a flowing solvent reactor

    Energy Technology Data Exchange (ETDEWEB)

    Begon, V.; Suelves, I.; Li, W.; Lazaro, M.-J.; Herod, A.A.; Kandiyoti, R. [Imperial College, London (United Kingdom). Dept. of Chemical Engineering and Chemical Technology

    2002-01-01

    Differences between the behaviour of coal macerals during liquefaction and catalytic hydrocracking were investigated. The liquefaction experiments were carried out in tetralin, using a flowing solvent reactor. The extracts were catalytically hydrocracked in a micro-bomb reactor, using a commercial catalyst. Conversions of the vitrinite and the liptinite concentrates during liquefaction were high ({approximately} 89%), while inertinite samples yielded a little over 20% extract. For inertinite, the emerging picture was consistent with high cross-link density. Liptinite was extracted less completely at lower temperatures and more slowly at high temperatures compared to corresponding vitrinites and vitrinitic coals. Long chain aliphatics released from the liptinite concentrate between 340 and 390{sup o}C appeared likely to have originated in lower molecular mass material occluded in the sample matrix and dissolving in tetralin prior to the onset of massive covalent bond scission. SEC chromatograms showed material of larger MMs in liptinite and vitrinite extracts than in the inertinite extract. The molecular mass distributions broadened with increasing extraction temperature. Catalytic hydrocracking experiments were carried out in a micro-bomb reactor for 10 and 120 min at 440{sup o}C, under 190 bar of hydrogen. In hydrocracking, the liptinite was the slowest extract to react at short reaction times ({approximately} 10 min). However, at longer reaction times, its products showed the smallest MM-distribution. Smaller differences were observed between the chromatograms of the 10 and 120 min hydrocracked products of the inertinite extract. Differences between spectra of the three extracts would strongly suggest the presence of larger (and apparently irreducible) polycyclic aromatic ring systems, in the hydrocracked products of the inertinite extract. 52 refs., 14 figs., 2 tabs.

  16. Catalytic Hydrothermal Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.

    2015-05-31

    The term “hydrothermal” used here refers to the processing of biomass in water slurries at elevated temperature and pressure to facilitate the chemical conversion of the organic structures in biomass into useful fuels. The process is meant to provide a means for treating wet biomass materials without drying and to access ionic reaction conditions by maintaining a liquid water processing medium. Typical hydrothermal processing conditions are 523-647K of temperature and operating pressures from 4-22 MPa of pressure. The temperature is sufficient to initiate pyrolytic mechanisms in the biopolymers while the pressure is sufficient to maintain a liquid water processing phase. Hydrothermal gasification is accomplished at the upper end of the process temperature range. It can be considered an extension of the hydrothermal liquefaction mechanisms that begin at the lowest hydrothermal conditions with subsequent decomposition of biopolymer fragments formed in liquefaction to smaller molecules and eventually to gas. Typically, hydrothermal gasification requires an active catalyst to accomplish reasonable rates of gas formation from biomass.

  17. Multi-Stage Production Inventory Problem in Petrochemical Industry%石油化工行业多阶段生产库存问题研究

    Institute of Scientific and Technical Information of China (English)

    郑孝妮; 刘国莉; 李大卫

    2012-01-01

    Production planning and inventory management as an important component of production management, play an important role in production and operation of enterprises. Based on the oil demand forecast and taking the economic henefits of enterprise-scale into account, multi-stage production inventory optimization model which is based on the changes of processing costs is established to minimize the production costs. The model demonstrate not only the impact of unit processing cost on the production plan, but also consider the finished goods inventory optimization, therefore, meet the business requirements of minimizing inventory costs. The adaptive weight particle swarm algorithm and simulated annealing - based particle swarm algorithm are used to solve the model, The experimental results show that simulated annealing based on the performance of PSO is better than the adaptive weight of the particle swarm algorithm, which can jump out of the local optimum and converge to the global optimum faster.%生产计划与库存管理作为生产管理重要的组成部分,对企业的生产运营起着重要的作用.以成品油需求量预测值为基础,在考虑企业规模经济效益的情况下,以最小化企业生产库存成本为目标,建立了基于变动加工成本的多阶段生产库存优化模型.该模型不仅体现了生产装置的单位加工成本对生产计划的影响,而且还考虑了产成品库存优化问题.因此,可满足企业对生产成本最小化的要求.最后,分别采用自适应权重的粒子群算法和基于模拟退火的粒子群算法对模型进行了优化求解.实验结果表明:基于模拟退火的粒子群算法的性能优于自适应权重的粒子群算法,这是因为前者跳出局部最优的速度较快,能有效地收敛于全局最优.

  18. Bioreactors for high cell density and continuous multi-stage cultivations: options for process intensification in cell culture-based viral vaccine production.

    Science.gov (United States)

    Tapia, Felipe; Vázquez-Ramírez, Daniel; Genzel, Yvonne; Reichl, Udo

    2016-03-01

    With an increasing demand for efficacious, safe, and affordable vaccines for human and animal use, process intensification in cell culture-based viral vaccine production demands advanced process strategies to overcome the limitations of conventional batch cultivations. However, the use of fed-batch, perfusion, or continuous modes to drive processes at high cell density (HCD) and overextended operating times has so far been little explored in large-scale viral vaccine manufacturing. Also, possible reductions in cell-specific virus yields for HCD cultivations have been reported frequently. Taking into account that vaccine production is one of the most heavily regulated industries in the pharmaceutical sector with tough margins to meet, it is understandable that process intensification is being considered by both academia and industry as a next step toward more efficient viral vaccine production processes only recently. Compared to conventional batch processes, fed-batch and perfusion strategies could result in ten to a hundred times higher product yields. Both cultivation strategies can be implemented to achieve cell concentrations exceeding 10(7) cells/mL or even 10(8) cells/mL, while keeping low levels of metabolites that potentially inhibit cell growth and virus replication. The trend towards HCD processes is supported by development of GMP-compliant cultivation platforms, i.e., acoustic settlers, hollow fiber bioreactors, and hollow fiber-based perfusion systems including tangential flow filtration (TFF) or alternating tangential flow (ATF) technologies. In this review, these process modes are discussed in detail and compared with conventional batch processes based on productivity indicators such as space-time yield, cell concentration, and product titers. In addition, options for the production of viral vaccines in continuous multi-stage bioreactors such as two- and three-stage systems are addressed. While such systems have shown similar virus titers compared to

  19. 多级离心泵流场优化及验证%Flow Field Optimization and Experimental Verification of Multi-stage Centrifugal Pumps

    Institute of Scientific and Technical Information of China (English)

    张权; 周盼; 率志君; 李玩幽

    2014-01-01

    Fluid exciting force is one of the important vibration sources of centrifugal pump which transmits outward through the pump shell and bearings. So, flow field optimization can effectively reduce the fluid exciting forces and vibration sources to improve the centrifugal pump’s vibration characteristic. In this paper, reduction of vibration and noise of a multi-stage centrifugal pump is studied. To begin with, CFD simulation technology is applied to optimize the flow field of the pump in the two aspects of cutting impeller and changing the shape of the volute. Then, the pressure pulsations and flow field excitation forces before and after the optimization are compared and analyzed. Afterwards, the method of cutting impeller is selected considering the requirements of processing technology. Finally the effectiveness is indirectly verified by analyzing the change of vibration response of the pump’s seats. The results show that cutting impeller and changing the tongue shape can reduce the pressure pulsation and fluid exciting force of the pump under blades’frequencies and octave frequencies, and the rear-seat vibration response after the cutting is reduced by 4 dB.%流体激励力是离心泵主要振源之一。通过对离心泵流场进行优化,可有效降低泵组流体激励力,减小离心泵振动。以多级离心泵的减振降噪为研究目的,运用CFD仿真技术从切割叶轮及改变蜗壳形状两个方面对流场进行优化。通过对比优化前后压力脉动以及流场激励力变化,说明优化情况。最后考虑加工工艺要求,选择切割叶轮的优化方法,并通过机脚振动响应的变化间接验证改善效果。结果表明:切割叶轮与改变隔舌形状对离心泵叶频及其倍频下的压力脉动与流体激励力都有减小,切割叶轮后机脚响应降低了4 dB。

  20. Coupled numerical simulation of the multi-stage rocket stage separation%火箭级间热分离过程耦合数值模拟

    Institute of Scientific and Technical Information of China (English)

    高立华; 张兵; 权晓波; 符松

    2011-01-01

    为了研究某火箭一、二级级间热分离的级间流动机理和分离过程的安全性,采用Chimera/Overset方法并结合N-S方程和刚体动力学方程,以流动和刚体动力学耦合计算的方式对该多级火箭的一、二级级间热分离过程进行了数值模拟。模拟结果显示,轴对称工况分离过程的流动存在剧烈的震荡,而二级喷管有偏转工况分离过程的流动比较平稳,在这两种工况下火箭都能够安全分离。研究结果表明,二级喷管偏转可以增进分离过程的平稳性。计算结果可为级间分离段的设计提供参考。%Coupled CFD and rigid body dynamics simulation was made using Chimera/Overset method to study the dynamic and aerodynamic characteristics of the stage separation of a multi-stage rocket.An axisymmetric case without the second stage nozzle rotation and a three-dimensional case with the second stage nozzle rotation were used to investigate the flow mechanism and safety of the stage separation.Simulation results show that the flow fields in the axisymmetric case features significant oscillation while those of the three-dimensional case are relatively smooth,with the rocket being able to safely separate in both cases,and that the second stage nozzle rotation has an effect on improving the stage separation stability.The simulation results provide a reference for the interstage design.

  1. Bioreactors for high cell density and continuous multi-stage cultivations: options for process intensification in cell culture-based viral vaccine production.

    Science.gov (United States)

    Tapia, Felipe; Vázquez-Ramírez, Daniel; Genzel, Yvonne; Reichl, Udo

    2016-03-01

    With an increasing demand for efficacious, safe, and affordable vaccines for human and animal use, process intensification in cell culture-based viral vaccine production demands advanced process strategies to overcome the limitations of conventional batch cultivations. However, the use of fed-batch, perfusion, or continuous modes to drive processes at high cell density (HCD) and overextended operating times has so far been little explored in large-scale viral vaccine manufacturing. Also, possible reductions in cell-specific virus yields for HCD cultivations have been reported frequently. Taking into account that vaccine production is one of the most heavily regulated industries in the pharmaceutical sector with tough margins to meet, it is understandable that process intensification is being considered by both academia and industry as a next step toward more efficient viral vaccine production processes only recently. Compared to conventional batch processes, fed-batch and perfusion strategies could result in ten to a hundred times higher product yields. Both cultivation strategies can be implemented to achieve cell concentrations exceeding 10(7) cells/mL or even 10(8) cells/mL, while keeping low levels of metabolites that potentially inhibit cell growth and virus replication. The trend towards HCD processes is supported by development of GMP-compliant cultivation platforms, i.e., acoustic settlers, hollow fiber bioreactors, and hollow fiber-based perfusion systems including tangential flow filtration (TFF) or alternating tangential flow (ATF) technologies. In this review, these process modes are discussed in detail and compared with conventional batch processes based on productivity indicators such as space-time yield, cell concentration, and product titers. In addition, options for the production of viral vaccines in continuous multi-stage bioreactors such as two- and three-stage systems are addressed. While such systems have shown similar virus titers compared to

  2. SURFACE-MODIFIED COALS FOR ENHANCED CATALYST DISPERSION AND LIQUEFACTION

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Yaw D. Yeboah

    1999-09-01

    This is the final report of the Department of Energy Sponsored project DE-FGF22-95PC95229 entitled, surface modified coals for enhanced catalyst dispersion and liquefaction. The aims of the study were to enhance catalyst loading and dispersion in coal for improved liquefaction by preadsorption of surfactants and catalysts on the coal and to train and educate minority scientists in catalysts and separation science. Illinois No. 6 Coal (DEC-24) was selected for the study. The surfactants investigated included dodecyl dimethyl ethyl ammonium bromide (DDAB), a cationic surfactant, sodium dodecyl sulfate, an anionic surfactant, and Triton x-100, a neutral surfactant. Ammonium molybdate tetrahydrate was used as the molybdenum catalyst precursor. Zeta potential, BET, FTIR, AFM, UV-Vis and luminescence intensity measurements were undertaken to assess the surface properties and the liquefaction activities of the coal. The parent coal had a net negative surface charge over the pH range 2-12. However, in the presence of DDAB the negativity of the surface charge decreased. At higher concentrations of DDAB, a positive surface charge resulted. In contrast to the effect of DDAB, the zeta potential of the coal became more negative than the parent coal in the presence of SDS. Adsorption of Triton reduced the net negative charge density of the coal samples. The measured surface area of the coal surface was about 30 m{sup 2}/g compared to 77m{sup 2}/g after being washed with deionized water. Addition of the surfactants decreased the surface area of the samples. Adsorption of the molybdenum catalyst increased the surface area of the coal sample. The adsorption of molybdenum on the coal was significantly promoted by preadsorption of DDAB and SDS. Molybdenum adsorption showed that, over a wide range of concentrations and pH values, the DDAB treated coal adsorbed a higher amount of molybdenum than the samples treated with SDS. The infrared spectroscopy (FTIR) and the atomic force

  3. 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.

  4. Influence of alkali catalyst on product yield and properties via hydrothermal liquefaction of barley straw

    DEFF Research Database (Denmark)

    Zhu, Z.; Toor, Saqib; Rosendahl, Lasse;

    2015-01-01

    Barley straw was successfully converted to bio-crude by hydrothermal liquefaction at temperature of 280 e400 C using an alkali catalyst (K2CO3) in our previous work, and the maximum bio-crude yield was obtained at 300 C. This paper extends previous work on studying liquefaction behavior of barley...

  5. Coal liquefaction. Quarterly report, January-March 1979. [US DOE supported

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    Progress in DOE-supported coal liquefaction pilot plant projects is reported: company, location, contract, funding, process description, history and progress in the current quarter. Related projects discussed are: coking and gasification of liquefaction plant residues, filtration of coal liquids and refining of coal liquids by hydrogenation. (LTN)

  6. Catalytic distillation process

    Science.gov (United States)

    Smith, Jr., Lawrence A.

    1982-01-01

    A method for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C.sub.4 feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

  7. Catalytic Functions of Standards

    NARCIS (Netherlands)

    K. Blind (Knut)

    2009-01-01

    textabstractThe three different areas and the examples have illustrated several catalytic functions of standards for innovation. First, the standardisation process reduces the time to market of inventions, research results and innovative technologies. Second, standards themselves promote the diffusi

  8. Multi-stage barites in partially melted UHP eclogite: implications for fluid/melt activities during deep continental subduction in the Sulu orogenic belt

    Science.gov (United States)

    Wang, Songjie; Wang, Lu

    2015-04-01

    . Zr-in-rutile thermometry shows their formation temperature to be 586-664 oC at 1.5-2.5 GPa. Barite-bearing MS inclusions with Ba-bearing K-feldspar (type-II) connected by Kfs+Pl+Bt veinlets of in-situ phengite breakdown and thin barite veinlets along grain boundaries (type-III) are products of phengite breakdown and induced fluid flow during exhumation. These barites have witnessed the gradational separation process of melt/ fluid from miscibility on/above the second critical endpoint during UHP metamorphism, to immiscibility along the exhumation path of the subducted slab. Associated reactions from pyrite to hematite and goethite with the type-III barite ring surrounding the pyrite provide evidence for a local high oxygen fugacity environment during eclogite partial melting and subsequent melt/fluid crystallization processes. Moreover, large grain barite aggregations (type-IV) modified by amphibole+albite symplectite are most likely formed by release of molecular and hydroxyl water from anhydrous minerals of eclogite during high-grade amphibolite-facies retrogression. The growth of multi-stage barites in UHP eclogite further advances our understanding of fluid/melt transfer, crystallization processes along the subduction-exhumation path of the partially melted eclogite, broadening our knowledge of melt/fluid evolution within subduction-collision zones worldwide. REFERENCES Chen Y.X., et al., 2014, Lithos, 200, 1-21. Liu J.B., et al., 2000, Acta Petrologica Sinica 16(4), 482-484. Zeng L.S., et al., 2007, Chinese Science Bulletin, 52(21), 2995-3001. Gao X.Y., et al., 2012, Journal of Metamorphic Geology, 30(2), 193-212.

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

    International Nuclear Information System (INIS)

    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.

  10. Catalytic ignition of light hydrocarbons

    Institute of Scientific and Technical Information of China (English)

    K. L. Hohn; C.-C. Huang; C. Cao

    2009-01-01

    Catalytic ignition refers to phenomenon where sufficient energy is released from a catalytic reaction to maintain further reaction without additional extemai heating. This phenomenon is important in the development of catalytic combustion and catalytic partial oxidation processes, both of which have received extensive attention in recent years. In addition, catalytic ignition studies provide experimental data which can be used to test theoretical hydrocarbon oxidation models. For these reasons, catalytic ignition has been frequently studied. This review summarizes the experimental methods used to study catalytic ignition of light hydrocarbons and describes the experimental and theoretical results obtained related to catalytic ignition. The role of catalyst metal, fuel and fuel concentration, and catalyst state in catalytic ignition are examined, and some conclusions are drawn on the mechanism of catalytic ignition.

  11. 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

  12. 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.

  13. Analysis of engineering cycles power, refrigerating and gas liquefaction plant

    CERN Document Server

    Haywood, R W

    1991-01-01

    Extensively revised, updated and expanded, the fourth edition of this popular text provides a rigorous analytical treatment of modern energy conversion plant. Notable for both its theoretical and practical treatment of conventional and nuclear power plant, and its studies of refrigerating and gas-liquefaction plant. This fourth edition now includes material on topics of increasing concern in the fields of energy 'saving' and reduction of environmental pollution. This increased coverage deals specifically with the following areas: CHP (cogeneration) plant, studies of both gas and coal burning p

  14. Rationale for continuing R&D in indirect coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Gray, D.; Tomlinson, G. [MITRE Corp., McLean, VA (United States)

    1995-12-31

    The objective of this analysis is to use the world energy demand/supply model developed at MITRE to examine future liquid fuels supply scenarios both for the world and for the United States. This analysis has determined the probable extent of future oil resource shortages and the likely time frame in which the shortages will occur. The role that coal liquefaction could play in helping to alleviate this liquid fuels shortfall is also examined. The importance of continuing R&D to improve process performance and reduce the costs of coal-derived transportation fuel is quantified in terms of reducing the time when coal liquids will become competitive with petroleum.

  15. Documenting Liquefaction Failures Using Satellite Remote Sensing and Artificial Intelligence Algorithms

    Science.gov (United States)

    Oommen, T.; Baise, L. G.; Gens, R.; Prakash, A.; Gupta, R. P.

    2009-12-01

    Historically, earthquake induced liquefaction is known to have caused extensive damage around the world. Therefore, there is a compelling need to characterize and map liquefaction after a seismic event. Currently, after an earthquake event, field-based mapping of liquefaction is sporadic and limited due to inaccessibility, short life of the failures, difficulties in mapping large aerial extents, and lack of resources. We hypothesize that as liquefaction occurs in saturated granular soils due to an increase in pore pressure, the liquefaction related terrain changes should have an associated increase in soil moisture with respect to the surrounding non-liquefied regions. The increase in soil moisture affects the thermal emittance and, hence, change detection using pre- and post-event thermal infrared (TIR) imagery is suitable for identifying areas that have undergone post-earthquake liquefaction. Though change detection using TIR images gives the first indication of areas of liquefaction, the spatial resolution of TIR images is typically coarser than the resolution of corresponding visible, near-infrared (NIR), and shortwave infrared (SWIR) images. We hypothesize that liquefaction induced changes in the soil and associated surface effects cause textural and spectral changes in images acquired in the visible, NIR, and SWIR. Although these changes can be from various factors, a synergistic approach taking advantage of the thermal signature variation due to changing soil moisture condition, together with the spectral information from high resolution visible, NIR, and SWIR bands can help to narrow down the locations of post-event liquefaction for regional documentation. In this study, we analyze the applicability of combining various spectral bands from different satellites (Landsat, Terra-MISR, IRS-1C, and IRS-1D) for documenting liquefaction failures associated with the magnitude 7.6 earthquake that occurred in Bhuj, India, in 2001. We combine the various spectral

  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. 大型离心压缩机性能预测的混合建模方法研究%Hybrid modeling method for performance prediction of multi-stage centrifugal compressor

    Institute of Scientific and Technical Information of China (English)

    褚菲; 王福利; 王小刚

    2011-01-01

    提出了一种核函数非线性偏最小二乘(PLS)与机理模型相结合的多级离心压缩机性能预测混合建模方法,用以预测离心压缩机的输出压比.通过分析大型离心压缩机多级压缩过程的机理,利用能最守恒关系,在压缩机各级气流损失计算和等熵效率定义的基础上建立了多级离心压缩机性能预测机理模型;利用核函数非线性PLS对机理模型的误差进行了修正.实验结果验证了该方法相比于机理模型的有效性,将其应用于实际生产过程中,取得了满意的效果.%A hybrid modeling method is proposed to predict the pressure ratio of multi-stage centrifugal compressor, which combines kernel nonlinear partial least squares (PLS) and principle model. Through analyzing the mechanism of multi-stage compression process, calculating airflow loss and defining isentropic efficiency, a principle model for performance prediction of multi-stage centrifugal compressor is established, and kernel nonlinear PLS is also used to correct the error of the principle model. Experiment analysis verifies the validity that the effectiveness of the method is better than that of ordinary principle model. The proposed method was applied to practical industrial process and result demonstrates that the method achieves satisfactory estimation performance.

  18. Performance Evaluation of the Multi-stage Tower-type Vertical-axis Wind Turbine%多层塔式H型立轴风机的性能分析

    Institute of Scientific and Technical Information of China (English)

    高振勋; 蒋崇文; 唐金龙; 王德宝

    2011-01-01

    The main ideal of the multi-stage tower type vertical-axis wind turbine is to utilize the superposition of multi group H-type vertical-axis wind turbines to generate power, and fully use the wind energy in different altitude, which is beneficial for the large-scale development of modern wind turbine. The performance compari sons between the multi-stage tower-type vertical-axis wind turbine and traditional wind turbine were performed on many aspects. It was pointed out that the multi-stage tower-type vertical-axis wind turbine can have many advantages, such as easy-machining blades, high power efficiency, avoidance of the yawing system, reasonable structure loading, and low manufacture/maintenance cost. However, some disadvantages exist, such as the aerodynamic drag brought in by the blade supporting structure, complicated tower construction, and incremental requirement for gearbox and shaft joint. Overall considering, the multi stage tower-type vertical-axis wind turbine has extensive prospect of market applications.%多层塔式立轴风机的核心思想是将多组H型立轴风机分层叠加组合发电,结构简单性能优异,非常适合大容量的风电机组,符合现代风机向大型化发展的方向。对多层塔式立轴风机与传统风机的多方面性能进行了对比,指出多层塔式立轴风机具有风能利用率高、叶片制造简单、无需偏航系统、结构载荷合理、制造维护成本低等诸多优点,但也存在一些缺点,如叶片支撑结构会引入气动阻力、塔架设计较复杂、需要多组齿轮箱及联轴器等。总体分析表明,多层塔式立轴风机的方案在技术上和经济上是可行的。

  19. 震后多品种应急物资多级配送中的选址-路径模型%Location-routing Model for Post-earthquake Multi-stage Distribution with Multi-type Emergency Supplies

    Institute of Scientific and Technical Information of China (English)

    杨恩缘; 李进; 严翌娴; 黄文耀

    2016-01-01

    地震发生后的应急物资配送是地震救援工作开展的关键。震后应急物资配送往往需要建立多级应急物流中心和规划物流中心间的配送路径,而且应急物资的需求具有多样性。基于这些特点,以总运输成本最小为目标,考虑应急物流中心的容量限制以及应急物资配送的多级性和多样性,建立了震后多品种应急物资多级配送选址-路径问题的混合整数规划模型。该模型选择由供应点、物资集散地、配送中心和需求点构成的多级配送网络,将帐篷、食物和药物作为应急救援物资。最后,采用一个汶川地震中物资配送的实例验证了模型的有效性和可行性。%The emergency supplydistribution for post-earthquakeis the key to earthquake relief work.It is nec-essary for post-earthquake emergency supply distribution to build multi-stage emergency logistics centers and deter-mine the distribution routesamong logistics centers.In addition,the demand for emergency supplies isdiversifica-tion.Based on these characteristics,minimizing the total transportation cost and considering the capacity constraints of emergency logistics centers and multi-stage and diversification of emergency supply distribution,we establishe a mixed interger programming model for location-routing problem of post-earthquake multi-stage distribution with multi-type emergency supplies.This model chooses the supply places,material centers,distribution centers and demand places as components of multi-stage distribution network,and regards the tents,food and drugs as emer-gency relief supplies.Finally,a supply distribution example in Wenchuan Earthquake to show the effecitveness and feasibility of the proposed model.

  20. Catalytic coherence transformations

    Science.gov (United States)

    Bu, Kaifeng; Singh, Uttam; Wu, Junde

    2016-04-01

    Catalytic coherence transformations allow the otherwise impossible state transformations using only incoherent operations with the aid of an auxiliary system with finite coherence that is not being consumed in any way. Here we find the necessary and sufficient conditions for the deterministic and stochastic catalytic coherence transformations between a pair of pure quantum states. In particular, we show that the simultaneous decrease of a family of Rényi entropies of the diagonal parts of the states under consideration is a necessary and sufficient condition for the deterministic catalytic coherence transformations. Similarly, for stochastic catalytic coherence transformations we find the necessary and sufficient conditions for achieving a higher optimal probability of conversion. We thus completely characterize the coherence transformations among pure quantum states under incoherent operations. We give numerous examples to elaborate our results. We also explore the possibility of the same system acting as a catalyst for itself and find that indeed self-catalysis is possible. Further, for the cases where no catalytic coherence transformation is possible we provide entanglement-assisted coherence transformations and find the necessary and sufficient conditions for such transformations.

  1. Direct liquefaction Proof-of-Concept facility. Final technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    Comolli, A.G.; Lee, L.K.; Pradhan, V.R.; Stalzer, R.H.; Harris, E.C.; Mountainland, D.M.; Karolkiewicz, W.F.; Pablacio, R.M.

    1995-08-01

    This report presents the results of work which included extensive modifications to HRI`s existing 3 ton per day Process Development Unit (PDU) and completion of the first PDU run. The 58-day Run 1 demonstrated scale-up of the Catalytic Two-Stage Liquefaction (CTSL Process) on Illinois No. 6 coal to produce distillate liquid products at a rate of up to 5 barrels per to of moisture-ash-free coal. The Kerr McGee Rose-SR unit from Wilsonville was redesigned and installed next to the US Filter installation to allow a comparison of the two solids removal systems. Also included was a new enclosed reactor tower, upgraded computer controls and a data acquisition system, an alternate power supply, a newly refurbished reactor, an in-line hydrotreater, interstage sampling system, coal handling unit, a new ebullating pump, load cells and improved controls and remodeled preheaters. Distillate liquid yields of 5 barrels/ton of moisture ash free coal were achieved. Coal slurry recycle rates were reduced from the 2--2.5 to 1 ratio demonstrated at Wilsonville to as low as 0.9 to 1. Coal feed rates were increased during the test by 50% while maintaining process performance at a marginally higher reactor severity. Sulfur in the coal was reduced from 4 wt% to ca. 0.02 wt% sulfur in the clean distillate fuel product. More than 3,500 gallons of distillate fuels were collected for evaluation and upgrading studies. The ROSE-SR Process was operated for the first time with a pentane solvent in a steady-state model. The energy rejection of the ash concentrate was consistently below prior data, being as low as 12%, allowing improved liquid yields and recovery.

  2. Liquefaction and Product Identification of Main Chemical Compositions of Wood in Phenol

    Institute of Scientific and Technical Information of China (English)

    Zhang Qiu-hui; Zhao Guang-jie; Jie Shu-jun

    2005-01-01

    To clarify liquefaction ratios and their construction variations of the main chemical compositions of wood in phenol using phosphoric acid as a catalyst, the chemical ingredients of wood such as holocellulose, cellulose and lignin, were measured and extracted according to GB methods. With Fourier transform infrared (FTIR), the product identification of reactant before and after liquefaction in phenol was investigated. The molecular weights and their distributions of the liquefaction results (acetone soluble parts) were studied by gel permeation chromatography (GPC). Results show that the molecular weights and their distributions of poplar and Chinese fir are almost the same. In poplar, the distribution of cellulose is the largest, and that of holocellulose the smallest after liquefaction. For Chinese fir, the distribution of holocellulose is the largest, and that of cellulose the smallest. After liquefaction of poplar cellulose, the change bands of FTIR spectrum observed below 1 600 cm-1, can be attributed to new substitute groups. The same is true for poplar lignin. For Chinese fir, the spectra of liquefaction results of all chemical compositions differ from that of wood meal. This reveals the more activity groups were produced because of the reactions between Chinese fir and phenol. The research shows that the liquefaction ratios of poplar decrease in the following order: holocellulose > lignin > cellulose, and those of Chinese fir in the order: lignin > cellulose > holocellulose.

  3. Examination of DMT-based methods for evaluating the liquefaction potential of soils

    Institute of Scientific and Technical Information of China (English)

    Gordon Tung-Chin KUNG; Der-Her LEE; Pai-Hsiang TSAI

    2011-01-01

    The flat dilatometer test(DMT)has the potential to be a useful tool in the evaluation ofliquefaction potential of soils.In practice,it is necessary to carefully examine existing DMT-based methods for evaluating liquefaction potential.We conducted the DMT and cone penetration test(CPT)in high liquefaction potential areas to examine the existing DMT-based methods for liquefaction potential evaluation.Specifically,the DMT and CPT were conducted side-by-side at each of six in-situ sites,and thus it is feasible to utilize those test results to validate the existing DMT-based methods.The DMT parameter,horizontal stress index(KD),is used as an indicator for estimating liquefaction resistance of soils in terms of cyclic resistance ratio(CRR).The analysis results revealed that the existing KD-based liquefaction evaluation methods would overestimate the CRR of soils,which leads to overestimation of the factor of safety against liquefaction.Also,the estimations of DMT-KD values by using the CPT-qc as well as the correlation between DMT-Ko and CPT-qc proposed by the previous studies would be significantly smaller than field measurements.The results reflected that further validation of the existing DMT-based methods for liquefaction evaluation is desirable.

  4. Liquefaction phenomena associated with the Emilia earthquake sequence of May–June 2012 (Northern Italy

    Directory of Open Access Journals (Sweden)

    Emergeo Working Group

    2013-04-01

    Full Text Available In this paper we present the geological effects induced by the 2012 Emilia seismic sequence in the Po Plain. Extensive liquefaction phenomena were observed over an area of ~ 1200 km2 following the 20 May, ML 5.9 and 29 May, ML 5.8 mainshocks; both occurred on about E–W trending, S dipping blind thrust faults. We collected the coseismic geological evidence through field and aerial surveys, reports from local people and Web-based survey. On the basis of their morphologic and structural characteristics, we grouped the 1362 effects surveyed into three main categories: liquefaction (485, fractures with liquefaction (768, and fractures (109. We show that the quite uneven distribution of liquefaction effects, which appear concentrated and aligned, is mostly controlled by the presence of paleo-riverbeds, out-flow channels and fans of the main rivers crossing the area; these terrains are characterised by the pervasive presence of sandy layers in the uppermost 5 m, a local feature that, along with the presence of a high water table, greatly favours liquefaction. We also find that the maximum distance of observed liquefaction from the earthquake epicentre is ~ 30 km, in agreement with the regional empirical relations available for the Italian Peninsula. Finally, we observe that the contour of the liquefaction observations has an elongated shape almost coinciding with the aftershock area, the InSAR deformation area, and the I ≥ 6 EMS area. This observation confirms the control of the earthquake source on the liquefaction distribution, and provides useful hints in the characterisation of the seismogenic source responsible for historical and pre-historical liquefactions.

  5. Parallel finite element modeling of earthquake ground response and liquefaction

    Institute of Scientific and Technical Information of China (English)

    Jinchi Lu(陆金池); Jun Peng(彭军); Ahmed Elgamal; Zhaohui Yang(杨朝晖); Kincho H. Law

    2004-01-01

    Parallel computing is a promising approach to alleviate the computational demand in conducting large-scale finite element analyses. This paper presents a numerical modeling approach for earthquake ground response and liquefaction using the parallel nonlinear finite element program, ParCYCLIC, designed for distributed-memory message-passing parallel computer systems. In ParCYCLIC, finite elements are employed within an incremental plasticity, coupled solid-fluid formulation. A constitutive model calibrated by physical tests represents the salient characteristics of sand liquefaction and associated accumulation of shear deformations. Key elements of the computational strategy employed in ParCYCLIC include the development of a parallel sparse direct solver, the deployment of an automatic domain decomposer, and the use of the Multilevel Nested Dissection algorithm for ordering of the finite element nodes. Simulation results of centrifuge test models using ParCYCLIC are presented. Performance results from grid models and geotechnical simulations show that ParCYCLIC is efficiently scalable to a large number of processors.

  6. 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.

  7. Mechanism of Liquefaction-Induced Large Settlements of Buildings

    Directory of Open Access Journals (Sweden)

    Zaheer Ahmed Almani

    2012-10-01

    Full Text Available In this paper, mechanism of liquefaction-related large settlements of the soil-structure system during the earthquake was studied using numerical modelling. The isolated shallow strip plane strain footing pad, supporting a typical simple frame structure, was founded on the ground at the shallow depth from the level ground surface. This system was modelled as plane-strain using the FLAC (Fast Lagrangian Analysis of continua 2D dynamic modelling and analysis code. This case focuses on the basic mechanisms of liquefaction-induced large deformations of the structure during an earthquake and will provide a benchmark model case for comparison with the model case in which jet grouted columns are provided as ground reinforcement. The results showed that large settlements of shallow foundations in punching shear are triggered during cyclic excitation. These large settlements under the structure are driven by load of structure and earthquake excitation. Monotonic shear deformation, lateral shear deformations and volume change of soil are main phenomena under the structure when the pore pressure rises and soil is liquefied in cyclic loading.

  8. [Progress in the studies of semen delayed liquefaction from chronic prostatitis].

    Science.gov (United States)

    Zhang, Yi-fei; Liang, Chao-zhao

    2007-01-01

    Chronic prostatitis (CP) is a common disease among adult men. It can result in male infertility mainly by alternating the semen quality, volume, pH, component, viscosity and liquefaction. There seems to be a strong association between CP and semen delayed liquefaction. Researches on the mechanism of semen delayed liquefaction resulting from CP mainly focus on the proteolytic ferment, plasminogen activator, prostate acid phosphatase, tissue factor, lack of zinc, and pH. This article briefly reviews the progress in these aspects. PMID:17302037

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

    OpenAIRE

    Shansong Gao; Dexiang Zhang; Kejian Li

    2015-01-01

    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 reacti...

  10. The Dual Role of Oxygen Functions in Coal Pretreatment and Liquefaction: Crosslinking and Cleavage Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Michael Serio; Erik Kroo; Sylvie Charpenay; Peter Solomon

    1993-09-30

    The overall objective of this project was to elucidate and model the dual role of oxygen functions in thermal pretreatment and liquefaction of low rank coals through the application of analytical techniques and theoretical models. The project was an integrated study of model polymers representative of coal structures, raw coals of primarily low rank, and selectively modified coals in order to provide specific information relevant to the reactions of real coals. The investigations included liquefaction experiments in microautoclave reactors, along with extensive analysis of intermediate solid, liquid and gaseous products. Attempts were made to incorporate the results of experiments on the different systems into a liquefaction model.

  11. Catalytic Conversion of Biofuels

    DEFF Research Database (Denmark)

    Jørgensen, Betina

    This thesis describes the catalytic conversion of bioethanol into higher value chemicals. The motivation has been the unavoidable coming depletion of the fossil resources. The thesis is focused on two ways of utilising ethanol; the steam reforming of ethanol to form hydrogen and the partial oxida...

  12. Catalytic Phosphination and Arsination

    Institute of Scientific and Technical Information of China (English)

    Kwong Fuk Yee; Chan Kin Shing

    2004-01-01

    The catalytic, user-friendly phosphination and arsination of aryl halides and triflates by triphenylphosphine and triphenylarsine using palladium catalysts have provided a facile synthesis of functionalized aryl phosphines and arsines in neutral media. Modification of the cynaoarisne yielded optically active N, As ligands which will be screened in various asymmetric catalysis.

  13. Catalytic efficiency of designed catalytic proteins.

    Science.gov (United States)

    Korendovych, Ivan V; DeGrado, William F

    2014-08-01

    The de novo design of catalysts that mimic the affinity and specificity of natural enzymes remains one of the Holy Grails of chemistry. Despite decades of concerted effort we are still unable to design catalysts as efficient as enzymes. Here we critically evaluate approaches to (re)design of novel catalytic function in proteins using two test cases: Kemp elimination and ester hydrolysis. We show that the degree of success thus far has been modest when the rate enhancements seen for the designed proteins are compared with the rate enhancements by small molecule catalysts in solvents with properties similar to the active site. Nevertheless, there are reasons for optimism: the design methods are ever improving and the resulting catalyst can be efficiently improved using directed evolution.

  14. Hydrothermal catalytic gasification of fermentation residues from a biogas plant

    International Nuclear Information System (INIS)

    Biogas plants, increasing in number, produce a stream of fermentation residue with high organic content, providing an energy source which is by now mostly unused. We tested this biomass as a potential feedstock for catalytic gasification in supercritical water (T ≥ 374 °C, p ≥ 22 MPa) for methane production using a batch reactor system. The coke formation tendency during the heat-up phase was evaluated as well as the cleavage of biomass-bound sulfur with respect to its removal from the process as a salt. We found that sulfur is not sufficiently released from the biomass during heating up to a temperature of 410 °C. Addition of alkali salts improved the liquefaction of fermentation residues with a low content of minerals, probably by buffering the pH. We found a deactivation of the carbon-supported ruthenium catalyst at low catalyst-to-biomass loadings, which we attribute to sulfur poisoning and fouling in accordance with the composition of the fermentation residue. A temperature of 400 °C was found to maximize the methane yield. A residence time dependent biomass to catalyst ratio of 0.45 g g−1 h−1 was found to result in nearly full conversion with the Ru/C catalyst. A Ru/ZrO2 catalyst, tested under similar conditions, was less active. -- Highlights: ► Fermentation residue of a biogas plant could be successfully liquefied with a low rate of coke formation. ► Liquefaction resulted in an incomplete removal of biomass-bound sulfur. ► Low catalyst loadings result in incomplete conversion, implicating catalyst deactivation. ► At 400 °C the observed conversion to methane was highest. ► A residence time dependent biomass to catalyst ratio of 0.45 g g−1 h−1 was determined to yield nearly complete conversion

  15. A General Criterion for Liquefaction in Granular Layers with Heterogeneous Pore Pressure

    CERN Document Server

    Goren, Liran; Aharonov, Einat; Sparks, David; Flekkøy, Eirik Grude

    2013-01-01

    Fluid-saturated granular and porous layers can undergo liquefaction and lose their shear resistance when subjected to shear forcing. In geosystems, such a process can lead to severe natural hazards of soil liquefaction, accelerating slope failure, and large earthquakes. Terzaghi's principle of effective stress predicts that liquefaction occurs when the pore pressure within the layer becomes equal to the applied normal stress on the layer. However, under dynamic loading and when the internal permeability is relatively small the pore pressure is spatially heterogeneous and it is not clear what measurement of pore pressure should be used in Terzaghi's principle. Here, we show theoretically and demonstrate using numerical simulations a general criterion for liquefaction that applies also for the cases in which the pore pressure is spatially heterogeneous. The general criterion demands that the average pore pressure along a continuous surface within the fluid-saturated granular or porous layer is equal to the appl...

  16. Liquefaction of sawdust in 1-octanol using acidic ionic liquids as catalyst.

    Science.gov (United States)

    Lu, Zexiang; Zheng, Huaiyu; Fan, Liwei; Liao, Yiqiang; Ding, Bingjing; Huang, Biao

    2013-08-01

    Acidic ionic liquids (AILs) as a novel catalyst in biomass liquefaction can accord with the demand of green chemistry and enhance the development of biomass thermal chemical conversion. A series of AILs containing HSO4- were synthesized by the imidazolium cation functionalization and applied to the Chinese fir sawdust liquefaction in 1-octanol in this paper. The experimental results showed that the liquefaction rate was gradually improved with the AILs acidity increasing, and reached 71.5% when 1-(4-sulfobutyl)-3-methylmidazolium hydrosulfate was used as catalyst with the 6:1 mass ratio of 1-octanol to sawdust at 423K after 60 min. Lignin, hemicellulose and cellulose were orderly desquamated, and then depolymerized and liquefied with the catalyst acidity increasing in the sawdust liquefaction process. The light oil was mainly composed of the octyl ether and the octyl ester compounds, suggesting that the solvent may play an important role in producing the high octane rating biofuel. PMID:23770997

  17. 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.

  18. Liquefaction of Tangier soils by using physically based reliability analysis modelling

    Directory of Open Access Journals (Sweden)

    Dubujet P.

    2012-07-01

    Full Text Available Approaches that are widely used to characterize propensity of soils to liquefaction are mainly of empirical type. The potential of liquefaction is assessed by using correlation formulas that are based on field tests such as the standard and the cone penetration tests. These correlations depend however on the site where they were derived. In order to adapt them to other sites where seismic case histories are not available, further investigation is required. In this work, a rigorous one-dimensional modelling of the soil dynamics yielding liquefaction phenomenon is considered. Field tests consisting of core sampling and cone penetration testing were performed. They provided the necessary data for numerical simulations performed by using DeepSoil software package. Using reliability analysis, the probability of liquefaction was estimated and the obtained results were used to adapt Juang method to the particular case of sandy soils located in Tangier.

  19. An improved method of evaluating liquefaction potential with the velocity of shear-waves

    Institute of Scientific and Technical Information of China (English)

    KE Han; CHEN Yun-min

    2000-01-01

    According to the results of cyclic triaxial tests, a linear correlation is presented between liquefaction resistance and elastic shear modulus, which shows the relation of Gmax (kPa) with (s d/2)1/2(kPa)1/2. When applied to soils from different sites, the correlation can be normalized in reference to its minimum void ratio (emin). Accordingly, an improved method is established to evaluate the liquefaction potential with shear-wave velocity. The critical shear-wave velocity of liquefaction is in linear relation with 1/4 power of depth and the maximum acceleration during earthquakes, which can be used to explain the phenomenon that the possibility of liquefaction decreases with the increment of the depth. Compared with previous methods this method turns out simple and effective, which is also verified by the results of cyclic triaxial tests,.

  20. 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.

  1. Experiment and mechanism of vibration liquefaction and compacting of saturated bulk solid

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The paper studies the probability of industrial application of vibration liquefaction of bulk solid from the opposite point of view, and proposing turning its harmful effects into benefits. Utilizing a new device of vibration liquefaction and by compacting saturated bulk solid, a set of additional device for experiment was designed. These experiments examined the problems related to vibration liquefaction of fine-ores and tailings on the basis of DSA-1 type direct shear apparatus, including models of straight tubes, curved tubes and a sandbox. The changing properties of tailings under vibration and the mechanism of vibration liquefaction and compacting of tailings were studied, and future application of the technique to mines has been put forward.

  2. Applied research and evaluation of process concepts for liquefaction and gasification of western coals. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wiser, W. H.

    1980-09-01

    Fourteen sections, including five subsections, of the final report covering work done between June 1, 1975 to July 31, 1980 on research programs in coal gasification and liquefaction have been entered individually into EDB and ERA. (LTN)

  3. 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.

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

    OpenAIRE

    Kim, J.; M. Kazama; Kwon, Y.

    2013-01-01

    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 e...

  5. A genetic algorithm approach for assessing soil liquefaction potential based on reliability method

    Indian Academy of Sciences (India)

    M H Bagheripour; I Shooshpasha; M Afzalirad

    2012-02-01

    Deterministic approaches are unable to account for the variations in soil’s strength properties, earthquake loads, as well as source of errors in evaluations of liquefaction potential in sandy soils which make them questionable against other reliability concepts. Furthermore, deterministic approaches are incapable of precisely relating the probability of liquefaction and the factor of safety (FS). Therefore, the use of probabilistic approaches and especially, reliability analysis is considered since a complementary solution is needed to reach better engineering decisions. In this study, Advanced First-Order Second-Moment (AFOSM) technique associated with genetic algorithm (GA) and its corresponding sophisticated optimization techniques have been used to calculate the reliability index and the probability of liquefaction. The use of GA provides a reliable mechanism suitable for computer programming and fast convergence. A new relation is developed here, by which the liquefaction potential can be directly calculated based on the estimated probability of liquefaction (), cyclic stress ratio (CSR) and normalized standard penetration test (SPT) blow counts while containing a mean error of less than 10% from the observational data. The validity of the proposed concept is examined through comparison of the results obtained by the new relation and those predicted by other investigators. A further advantage of the proposed relation is that it relates and FS and hence it provides possibility of decision making based on the liquefaction risk and the use of deterministic approaches. This could be beneficial to geotechnical engineers who use the common methods of FS for evaluation of liquefaction. As an application, the city of Babolsar which is located on the southern coasts of Caspian Sea is investigated for liquefaction potential. The investigation is based primarily on in situ tests in which the results of SPT are analysed.

  6. Numerical simulation of liquefaction behaviour of granular materials using Discrete Element Method

    Indian Academy of Sciences (India)

    T G Sitharam; S V Dinesh

    2003-09-01

    In this paper, numerical simulation of 3-dimensional assemblies of 1000 polydisperse sphere particles using Discrete Element Method (DEM) is used to study the liquefaction behaviour of granular materials. Numerical simulations of cyclic triaxial shear tests under undrained conditions are performed at different confining pressures under constant strain amplitude. Results obtained in these numerical simulations indicate that with increase in confining pressure there is an increase in liquefaction resistance.

  7. Low Severity Coal Liquefaction Promoted by Cyclic Olefins

    Energy Technology Data Exchange (ETDEWEB)

    Christine W. Curtis

    1998-04-09

    The development of the donor solvent technology for coal liquefaction has drawn a good deal of attention over the last three decades. The search for better hydrogen donors led investigators to a class of compounds known as cyclic olefins. Cyclic olefins are analogues of the conventional hydroaromatic donor species but do not contain aromatic rings. The cyclic olefins are highly reactive compounds which readily release their hydrogen at temperatures of 200 C or higher. Considerable effort has been o expended toward understanding the process of hydrogen donation. Most of this work was conducted in bomb reactors, with product analysis being carried out after the reaction was complete. Efforts directed towards fundamental studies of these reactions in situ are rare. The current work employs a high temperature and high pressure infrared cell to monitor in situ the concentrations of reactants and products during hydrogen release from hydrogen donor compounds.

  8. Experimental Study of Subcritical Water Liquefaction of Biomass

    DEFF Research Database (Denmark)

    Zhu, Zhe; Toor, Saqib; Rosendahl, Lasse;

    2014-01-01

    (woody and non-woody) on the biomass conversion, bio-crude yield, and the qualities of products were studied. The results suggested that the addition of potassium carbonate as catalyst showed a positive effect on bio-crude yield, especially for wood, where it was enhanced to 47.48 wt%. Macroalgae showed...... found that the addition of K2CO3 lowered the solids quality in terms of the heating values, while it did not have apparent effect on the functional groups of solid residues. SEM analysis of the raw biomass and solid residues revealed that the char formation for wood, sawdust and macroalgae had initially......In this work, hydrothermal liquefaction (HTL) of wood industry residues (wood, bark, sawdust) and macroalgae for producing biofuels has been investigated under subcritical water conditions (at temperature of 300 C), with and without the presence of catalyst. The effects of catalyst and biomass type...

  9. Helium liquefaction with a 4 K pulse tube cryocooler

    Science.gov (United States)

    Wang, Chao

    2001-07-01

    Helium liquefaction with a two-stage 4 K pulse tube cryocooler is introduced in this paper. The helium liquefier has a feature of precooling helium gas to be liquefied by using inefficiency of the second stage regenerator in the pulse tube cryocooler. This process reduces enthalpy of the incoming helium gas when entering the condenser and significantly increases the condensation rate. Numerical analysis predicts the precooling heat load on the second stage regenerator, decreases the PTC second stage cooling capacity by only 11% of the heat actually absorbed into the regenerator. A prototype pulse tube helium liquefier was built, which has two precooling heat exchangers on the first stage cold head and the second stage regenerator. It continuously liquefies helium with a rate of 4.8 l/day under normal pressure while consumes 4.6 kW power input.

  10. Co-liquefaction of Enriched Coal Maceral Constituents and Sawdust

    Institute of Scientific and Technical Information of China (English)

    王炀; 李庭琛; 任铮伟; 颜涌捷

    2002-01-01

    Co-liquefaction of coal and sawdust was studied in the presence of hydrogen-donor solvent, tetralin. Coal samples were prepared through floatation of the Xinwen coal, followed by enrichment of maceral constituents. Sample I was rich in vitrinite and Sample II fusinite. Effects of reaction temperature, time and initial cold H2 pressure were studied on conversion, yield, especially oil yield, through comparison between these two samples. Because it is more difficult to be liquefied, Sample II, is greatly affected by changes in temperature and time. However, it is almost independent of change in initial cold H2 pressure, owing to the role of tetralin as hydrogen vehicle. Certain product(s) formed from thermolysis of sawdust can help hydrogenation of the intermediate (asphaltene and preasphaltene) in further forming oil products.

  11. Fundamental studies of retrograde reactions in direct liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Serio, M.A.; Solomon, P.R.; Kroo, E.; Charpenay, S.; Bassilakis, R.

    1991-12-17

    The overall objective of the program was to improve the understanding of retrograde reactions and their dependencies on coal rank and structure, and/or coal modifications and reaction conditions. Because retrograde reactions are competitive with bond breaking reactions, an understanding of both is required to shift the competition in favor of the latter. Related objectives were to clarify the conflicting observations reported in literature on such major topics as the role of oxygen groups in retrograde reactions and to provide a bridge from very fundamental studies on pure compounds to phenomenological studies on actual coal. This information was integrated into the FG-DVC model, which was improved and extended to the liquefaction context.

  12. 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......, and reached 38.4 wt% after three cycles. The HHVs of bio-crude oil from HTL with aqueous phase were 28.4–29.4 MJ/kg, slightly higher than those from HTL with fresh water. While no obvious differences in elemental distribution can be found after aqueous phase recirculation. In conclusion, this study gives...... a detailed insight into the HTL behavior of barley straw, and offers potential opportunities and benefits for bio-crude oil production through the reuse of aqueous phase....

  13. Economics of hydrogen production and liquefaction updated to 1980

    Science.gov (United States)

    Baker, C. R.

    1979-01-01

    Revised costs for generating and liquefying hydrogen in mid-1980 are presented. Plant investments were treated as straight-forward escalations resulting from inflation. Operating costs, however, were derived in terms of the unit cost of coal, fuel gas and electrical energy to permit the determination of the influence of these parameters on the cost of liquid hydrogen. Inflationary influence was recognized by requiring a 15% discounted rate of return on investment for Discounted Cash Flow financing analysis, up from 12% previously. Utility financing was revised to require an 11% interest rate on debt. The scope of operation of the hydrogen plant was revised from previous studies to include only the hydrogen generation and liquefaction facilities. On-site fuel gas and power generation, originally a part of the plant complex, was eliminated. Fuel gas and power are now treated as purchased utilities. Costs for on-site generation of fuel gas however, are included.

  14. Effect of microwave pretreatment on liquefaction of low-rank Mukah Balingian Malaysian coal

    Energy Technology Data Exchange (ETDEWEB)

    Mohd Azlan Mohd Ishak; Khudzir Ismail; Mohd Fauzi Abdullah; Nur Nasulhah Kasim [University Technology MARA, Perlis (Malaysia). Fuel Combustion Research Laboratory

    2007-07-01

    The effect of microwave pretreatment on low-rank Malaysian coal towards coal conversion and oil+gas yield during direct liquefaction was investigated. The pretreatment on coal was carried out prior to liquefaction using a conventional variable power microwave oven at 150, 300 and 600 W for a period of 1 to 15 min. Liquefaction processes were carried out in a 1-liter high-pressure high-temperature batch-wise reactor with tetralin as a hydrogen-donor solvent, at temperature of 420{sup o}C and at 4 MPa nitrogen pressure. The DTG results of the pyrolysed microwave-treated samples via thermogravimetric analysis (TGA) showed the increased in coal reactivity in comparison to the untreated sample. The coal conversion and oil+gas yield obtained from the liquefaction of the pretreated coal under various pretreatment conditions showed an increase of up to 3 - 7 and 9 - 22 %, respectively. The significant increased of oil+gas yield at less severe liquefaction temperature on the microwave-irradiated samples might be due to the cracks and fissures formed as shown by Scanning Electron Microscope (SEM), and the weaken coal structure (C-C bonds) that probably occurred during the microwave pretreatment to facilitate the diffusion of solvent into the coal structure. Thus, this new and effective pretreatment on coal could be a promising approach in enhancing coal conversion and oil+gas yield that utilises a less severe temperature for coal liquefaction. 22 refs., 4 figs., 5 tabs.

  15. Coal liquefaction process streams characterization and evaluation. Volume 2, Participants program final summary evaluation

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-05-01

    This 4.5-year project consisted of routine analytical support to DOE`s direct liquefaction process development effort (the Base Program), and an extensive effort to develop, demonstate, and apply new analytical methods for the characterization of liquefaction process streams (the Participants Program). The objective of the Base Program was to support the on-going DOE direct coal liquefaction process development program. Feed, process, and product samples were used to assess process operations, product quality, and the effects of process variables, and to direct future testing. The primary objective of the Participants Program was to identify and demonstrate analytical methods for use in support of liquefaction process develpment, and in so doing, provide a bridge between process design, development, and operation and analytical chemistry. To achieve this direct coal liquefaction-derived materials. CONSOL made an evaluation of each analytical technique. During the performance of this project, we obtained analyses on samples from numerous process development and research programs and we evaluated a variety of analytical techniques for their usefulness in supporting liquefaction process development. Because of the diverse nature of this program, we provide here an annotated bibliography of the technical reports, publications, and formal presentations that resulted from this program to serve as a comprehensive summary of contract activities.

  16. 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.

  17. Fabric Behavior of Sand in Post-liquefaction

    Directory of Open Access Journals (Sweden)

    Seyed Amirodin Sadrnejad

    2005-01-01

    Full Text Available An anisotropic plasticity model for post-liquefaction of the undrained behavior of sand is presented. The model incorporates the critical/steady state concept that postulates the existence of a state where sand continuously deforms at a certain constant effective stress depending two main parameters of both initial bulk parameters (void ratio or relative density and the stress level (mean stress. The local instability of saturated sand within post-liquefaction is highly dependent on the residual inherent/induced anisotropy, bedding plane effects and stress/strain path. Most of the models developed using stress/strain invariants are not capable of identifying the parameters depending on orientation such as fabric. This is mainly because stress/strain invariants are quantities similar to scalar quantities and not capable of carrying directional information with them. The constitutive equations of the model are derived within the context of non-linear elastic behavior of the whole medium and plastic sliding of interfaces of predefined multi-planes. The proposed multi-plane based model is capable of predicting the behavior of soils on the basis of plastic sliding mechanisms, elastic behavior of particles and possibilities to see the micro-fabric effects as natural anisotropy as well as induced anisotropy in plasticity. The model is capable of predicting the behavior of soil under different orientation of bedding plane, history of strain progression during the application of any stress/strain paths. The influences of rotation of the direction of principal stress and strain axes and induced anisotropy are included in a rational way without any additional hypotheses. The spatial strength distribution at a location as an approximation of probable mobilized sliding mechanism is proposed as an ellipsoid function built up on bedding plane.

  18. Microbial liquefaction of peat for the production of synthetic fuels

    Energy Technology Data Exchange (ETDEWEB)

    Gunasekaran, M.

    1988-01-01

    Objectives of this study were: to evaluate the potential of using various microorganisms to hydrolyse and liquify peat; to determine the optimal conditions for peat hydrolysis and liquefaction; to study the co-metabolizable substances; to separate the compounds present in liquified peat by alumina and silica acid chromatography and capillary gas chromatography; and to identify the compounds in liquified peat by capillary GC-Mass spectrometry. Organisms used in the study include: Coprinus comatus, Coriolus hirsutus, Ganoderma lucidum, Lentinus edodes, Lenzites trabea, Phanerochaete chrysosporium, Pleurotus ostreatus, P. sapidus, Polyporus adjustus, Neurospora sitophila, Rhizophus arrhizus, Bacillus subtilis, Acinetobacter sp. and Alcaligenes sp. The fungi were maintained and cultivated in potato dextrose agar at 30 C. The bacteria were maintained in nutrient agar at 30 C. We have also initiated work on coal solubilization in addition to the studies on peat liquefaction. A relatively new substratum or semi-solid base for culture media called Pluronic F-127, or Polyol (BASF, New Jersey). Objectives of this study were: (1) to study the growth patterns of Candida ML 13 on pluronic as substratum; (2) to determine the rate of microbial coal solubilization on pluronic F-127 amended in different growth media; (3) to separate the mycelial mat of Candida ML 13 from unsolubilized coal particles and solubilized coal products from pluronic F-127; (4) to determine the effects of pH on microbial coal solubilization in pluronic F-127 media; (5) the effect of concentration of pluronic F-127 in media on coal solubilization; and, (6) to study the role of extracellular factors secreted by Candida ML 13 on coal solubilization in pluronic F-127 media. Results are discussed. 4 refs.

  19. Impact of seismic hazard characterization on probability of liquefaction

    International Nuclear Information System (INIS)

    The objective of this paper is to assess the sensitivity of safety factor against the onset of liquefaction to the characteristics of the seismic hazard data defined for the site. The site considered is a deep soil site, approximately 1,000 feet thick, for which hazard, laboratory and field geophysical data are available. The uniform hazard spectra (UHS) defined at the rock outcrop at a given return period are used to define the characteristics of the ground motion input to the site. Using a Monte Carlo procedure, a large number of input ground motions (500 cases) are defined at the rock outcrop. For each soil column analysis, peak induced shear stresses are then calculated throughout the soil overburden using the concept of upward propagating shear waves through the one dimensional soil column. Shear modulus and hysteretic damping characteristics used in these calculations are consistent with the experimental data available for the site. Corresponding soil shear strengths are estimated from Standard Penetration Test (SPT) blow count data determined from the site field investigation program. The Seed empirical correlations are used to estimate the soil shear strength or capacity needed to define the onset of liquefaction. Since the SPT blow counts are found to be essentially independent of shear wave velocity measurements at the site' blow counts for strength estimates are randomly selected from the available data for each soil layer to estimate shear strength. The median values of safety factors and their variability are then found for easy layer by analyzing the computed safety factors from each of the convolution calculations

  20. Prediction of liquefaction potential based on CPT up-sampling

    Science.gov (United States)

    Sadoghi Yazdi, Javad; Kalantary, Farzin; Sadoghi Yazdi, Hadi

    2012-07-01

    Cone penetration test data has been widely used for determination of the threshold of seismically induced soil liquefaction. However, possible inaccuracies in the collected data from case histories as well as natural variability of parameters and other uncertainties associated with natural phenomenon have yet prohibited a conclusive definition for this threshold. Various classification techniques have been used to define the most reliable correlations. However, available liquefied to non-liquefied data imbalance has caused learning bias to the majority class in the learning model of the pattern recognition systems. This has adversely affected the outcome of such approaches and in order to overcome this problem Support Vector Data Description (SVDD) strategy is employed to "up sample" the minority data. In other words SVDD, which is robust against noisy samples, is used to generate virtual data points for the minority class, bearing the same characteristics as the non-virtual samples. In order to specify the most appropriate data range a sphere boundary around the main body of the data are sought through an optimization process. The data inside the obtained boundary are the target data and the ones outside it are the outliers or so-called "noise", to be neglected. This procedure reduces the issue of class intermixture in the fringe zone and produces relatively well defined class that then is fed into the Adaptive Neuro-Fuzzy Inference System (ANFIS) classifier for determination of liquefaction potential. The predictions are then examined to evaluate the reliability and validation of the overall technique and compared with other prediction methods using confusion matrix. It is shown that the overall accuracy of the proposed technique is higher than all previously proposed methods and only equal to the Support Vector Machine (SVM) technique. Furthermore an improvement in the F-score of the non-liquefied data recognition has been achieved in relation to all previously

  1. Catalytic thermal barrier coatings

    Science.gov (United States)

    Kulkarni, Anand A.; Campbell, Christian X.; Subramanian, Ramesh

    2009-06-02

    A catalyst element (30) for high temperature applications such as a gas turbine engine. The catalyst element includes a metal substrate such as a tube (32) having a layer of ceramic thermal barrier coating material (34) disposed on the substrate for thermally insulating the metal substrate from a high temperature fuel/air mixture. The ceramic thermal barrier coating material is formed of a crystal structure populated with base elements but with selected sites of the crystal structure being populated by substitute ions selected to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a higher rate than would the base compound without the ionic substitutions. Precious metal crystallites may be disposed within the crystal structure to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a lower light-off temperature than would the ceramic thermal barrier coating material without the precious metal crystallites.

  2. A catalytic cracking process

    Energy Technology Data Exchange (ETDEWEB)

    Degnan, T.F.; Helton, T.E.

    1995-07-20

    Heavy oils are subjected to catalytic cracking in the absence of added hydrogen using a catalyst containing a zeolite having the structure of ZSM-12 and a large-pore crystalline zeolite having a Constraint Index less than about 1. The process is able to effect a bulk conversion of the oil at the same time yielding a higher octane gasoline and increased light olefin content. (author)

  3. A characterization and evaluation of coal liquefaction process streams. The kinetics of coal liquefaction distillation resid conversion

    Energy Technology Data Exchange (ETDEWEB)

    Klein, M.T.; Calkins, W.H.; Huang, H.; Wang, S.; Campbell, D.

    1998-03-01

    Under subcontract from CONSOL Inc., the University of Delaware studied the mechanism and kinetics of coal liquefaction resid conversion. The program at Delaware was conducted between August 15, 1994, and April 30, 1997. It consisted of two primary tasks. The first task was to develop an empirical test to measure the reactivity toward hydrocracking of coal-derived distillation resids. The second task was to formulate a computer model to represent the structure of the resids and a kinetic and mechanistic model of resid reactivity based on the structural representations. An introduction and Summary of the project authored by CONSOL and a report of the program findings authored by the University of Delaware researchers are presented here.

  4. 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.

  5. 78 FR 15715 - Excelerate Liquefaction Solutions I, LLC; Lavaca Bay Pipeline System, LLC; Notice of Intent To...

    Science.gov (United States)

    2013-03-12

    ... liquefaction, centrifugal refrigerant compressors, and associated infrastructure; Mooring structures and... (examples include construction right-of-way, contractor/pipe storage yards, compressor stations, and...

  6. Stratigraphic control on earthquake-induced liquefaction: A case study from the Central Po Plain (Italy)

    Science.gov (United States)

    Amorosi, A.; Bruno, L.; Facciorusso, J.; Piccin, A.; Sammartino, I.

    2016-11-01

    Studies on earthquake-induced liquefaction tied to high-resolution stratigraphic analysis have been rarely undertaken. We report the results of a multidisciplinary study from the Quistello-Moglia area, in the central Po Plain (northern Italy). In this region, combined stratigraphic, sedimentological, geotechnical, and geochemical data allowed assessment of liquefaction potential and identification of the primary source for liquefaction, following the second main shock (Mw ~ 6) of the 2012 Po Plain earthquake. Using Cone Penetration Test (CPT)-based simplified procedures for liquefaction hazard evaluation, we assessed the highest liquefaction potential of Holocene, fluvial-channel and related (crevasse/levee) fine sand-silt facies encased in thick, mud-prone floodplain and swamp successions. The liquefaction potential, and the intensity of the manifestations induced on the ground surface, decreased for the vertically-amalgamated, sheet-like Pleistocene sandy fluvial units encountered at depths greater than 13 m. Floodplain and swamp deposits were virtually non-liquefiable. In the Quistello area, the compositional characterization of sands that were liquefied and extruded during the 2012 earthquake reveals the diagnostic geochemical fingerprint of sediment carried by the Po River, as opposed to the Apennine composition of surficial sediments. These data rule out proximity of liquefied layers to the surface, and attest the buried, meandering Po River system at depths of ~ 7-10 m most likely representing the source for the liquefied sand that vented to the surface. Similarly, at Moglia, liquefied sands were likely sourced from loose and saturated, ribbon-shaped, fluvial sand bodies encased in mud, though at shallower (4-7 m) depths. Pronounced liquefaction phenomena in alluvial plain systems are commonly believed to be associated primarily with elongate topographic ridges following paleo-river courses. Here, we document that under favorable stratigraphic conditions

  7. Multisensor and Multispectral Approach in Documenting and Analyzing Liquefaction Hazard using Remote Sensing

    Science.gov (United States)

    Oommen, T.; Baise, L. G.; Gens, R.; Prakash, A.; Gupta, R. P.

    2008-12-01

    Seismic liquefaction is the loss of strength of soil due to shaking that leads to various ground failures such as lateral spreading, settlements, tilting, and sand boils. It is important to document these failures after earthquakes to advance our study of when and where liquefaction occurs. The current approach of mapping these failures by field investigation teams suffers due to the inaccessibility to some of the sites immediately after the event, short life of some of these failures, difficulties in mapping the aerial extent of the failure, incomplete coverage etc. After the 2001 Bhuj earthquake (India), researchers, using the Indian remote sensing satellite, illustrated that satellite remote sensing can provide a synoptic view of the terrain and offer unbiased estimates of liquefaction failures. However, a multisensor (data from different sensors onboard of the same or different satellites) and multispectral (data collected in different spectral regions) approach is needed to efficiently document liquefaction incidences and/or its potential of occurrence due to the possibility of a particular satellite being located inappropriately to image an area shortly after an earthquake. The use of SAR satellite imagery ensures the acquisition of data in all weather conditions at day and night as well as information complimentary to the optical data sets. In this study, we analyze the applicability of the various satellites (Landsat, RADARSAT, Terra-MISR, IRS-1C, IRS-1D) in mapping liquefaction failures after the 2001 Bhuj earthquake using Support Vector Data Description (SVDD). The SVDD is a kernel based nonparametric outlier detection algorithm inspired by the Support Vector Machines (SVMs), which is a new generation learning algorithm based on the statistical learning theory. We present the applicability of SVDD for unsupervised change-detection studies (i.e. to identify post-earthquake liquefaction failures). The liquefaction occurrences identified from the different

  8. 多级串联高压大功率矩阵变换器的研究%Research on Multi-stage Series-connection High-voltage High-power Matrix Converter

    Institute of Scientific and Technical Information of China (English)

    蒋婷; 江剑锋; 曹中圣; 杨喜军

    2012-01-01

    提出和采用载波移相调制原理,仿真分析一种降压变压器次级绕组功率平衡的多级串联高压变频器,即一个次级变压器承担对称的3个三相-单相矩阵变换器输出,输出相位相同的三相-单相矩阵变换器通过升压变压器次级串联,构成一相高压交流输出.整个电路由网侧工频降压变压器、单相矩阵变换器阵列、载侧高频升压变压器以及滤波电路构成.仿真结果表明,所提出的多级串联高压变频器具有可行性和低成本特征.%Based on carrier wave phase-shifted modulation, a multi-stage series-connection high voltage frequency converter with balanced output power of the step-down transformer's secondary windings was given,in which a winding burdens three symmetry three-phase to single-phase MC outputs and the same phase outputs of the MC are cascaded at the secondary side of the transformers,letting out one phase of high-voltage AC output. The circuit is consisted of a step-down industry frequency transformer at the network side,three-phase to single-phase MC arrays, a step-up high frequency transformer at the load side and filter components. The simulation result based on Matlab/Simulink shows that the proposed multi-stage series-connection high voltage frequency converter is feasible and low-cost.

  9. Barrier-oxide layer engineering of TiO{sub 2} nanotube arrays to get single- and multi-stage Y-branched nanotubes: Effect of voltage ramping and electrolyte conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Anitha, V.C. [School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Banerjee, Arghya Narayan, E-mail: arghya@ynu.ac.kr [School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Joo, Sang Woo, E-mail: swjoo@yu.ac.kr [School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Min, Bong Ki [Center for Research Facilities, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of)

    2015-05-15

    Highlights: • Single and multi-stage Y-branched TiO{sub 2} nanotube arrays fabricated successfully. • Effect of voltage ramping down process on the branching of nanotube revealed. • Unequal interfacial movement across barrier layer of nanotubes manifests branching. • By controlling thinning of barrier oxide layer different morphologies of TNAs fabricated. • Y-branched, stacked double layer, mixture of broken/branched and multi-branched TNAs formed. - Abstract: Single and multi-stage Y-branched TiO{sub 2} nanotube arrays (TNAs) have been fabricated by a voltage ramping down process using potentiostatic two-step anodization in 0.5 wt% hydrofluoric acid (HF)/glycerol (1:2 volume ratio) electrolyte. Initially, the voltage is kept at 40 V for 3 h and then it is ramped down to different voltages (e.g. 30 V, 34 V, 36 V, 38 V and 39 V) at a ramping rate of either −1.0 V s{sup −1} or −0.5 V s{sup −1} in one time and two-time aged electrolytes. The growth mechanism of Y-branching of TNAs is modeled and explained in terms of unequal interfacial movements of the two interfaces across the barrier oxide layer (BOL) under non-steady-state growth regime. The ‘pinched off’ area of the BOL at the nanotube propagation front can be controlled effectively with the relative ramping voltage levels and electrolyte's conductivity to obtain Y-branched TNAs.

  10. 基于Orness测度约束的多阶段灰色局势群决策模型%Multi-stage grey situation group decision-making model based on Orness

    Institute of Scientific and Technical Information of China (English)

    张娜; 方志耕; 朱建军

    2015-01-01

    研究多阶段灰色局势群决策模型。从决策专家各阶段的评价信息质量分析入手,给出了评价阶段质变和量变的定义;基于各阶段的评价信息和Orness测度,构建以相邻阶段信息偏差最小为目标的时间权重模型,分析了在保持最优局势不变的情况下Orness测度的取值范围,为决策专家Orness取值提供参考;研究基于群体差异最小的决策专家权重模型,提出一种多阶段灰色局势群决策评价信息集结方法。最后,通过一个具体的算例说明了该方法的有效性和可行性。%A multi-stage situation group decision-making model is studied. Based on the quality analysis on decision experts’ evaluation information, the qualitative change and quantitative change of evaluation stages are defined. Then a time weight model minimizing the information deviation for adjacent stages is built, and the value range of Orness measure with the unchanged optimal situation is analyzed, which provides a reference for decision experts to assign the value. A new method for information aggregation is proposed for multi-stage grey situation group decision-making. Finally, a specific example illustrates the effectiveness and feasibility of the proposed method.

  11. 服务系统中多阶段动态服务匹配模型及优化算法研究%Modeling and Optimization of Multi-Stage Dynamic Service Matchmaking for Service Systems

    Institute of Scientific and Technical Information of China (English)

    潘海侠; 王晶

    2012-01-01

    In a multi-stage service process, for each stage, there are many alternative service matchmaking options. The decision made at each stage directly impacts the cost and the related requirements of the next phase of service matchmaking. Therefore, dynamic service matchmaking presents a great challenge to the service resource planning. Thus, global optimization is vitally important to a successful service system. With the fpcus on the dynamic service match-making in service supply system, a dynamic service matchmaking model is developed to describe multi-stage dynamic decision making process. Then, dynamic programming method is used to solve the global optimization matchmaking problem. Finally, a case study is conducted to demonstrate the proposed method.%在服务系统的多阶段服务过程中,每阶段有多种服务匹配选项,匹配决策直接影响到服务成本和下一阶段匹配的相关需求.因此,着眼于服务过程全局动态服务匹配模型及其优化算法成为动态服务匹配服务资源优化的关键因素.重点研究了服务系统中的多阶段、多选项的动态服务匹配问题,给出了多阶段动态服务匹配的模型描述,采用动态规划算法进行多阶段全局优化,最后通过实例给出了进一步说明.

  12. 基于多阶段复合实物期权的风力发电项目投资决策%Investment decision-making based on multi-stage compound real options for wind power generation

    Institute of Scientific and Technical Information of China (English)

    丁乐群; 徐越; 刘琰; 王宇拓; 韩强

    2012-01-01

    在电力市场环境下,建立风力发电项目多阶段、多不确定因素的复合实物期权决策框架.根据风力发电项目投资过程中存在的不确定因素的特征,分别建立发电量、上网电价、低碳收益的随机变化模型;通过使用蒙特卡罗模拟法和二叉树方法,提出求解多阶段、多不确定因素的风力发电项目的投资决策的模型和求解步骤.通过实例对所提方法实现步骤进行了说明,并将所提方法与净现值(NPV)法进行了对比,结果证明了所提方法的优越性.%A multi-stage decision-making framework with compound real options is set for a wind farm project with multiple uncertain factors in the electricity market environment. The random changing models are established for uncertain factors of wind power generation investment:annual power production,electricity price and low-carbon benefits. The investment decision-making model using Monte Carlo simulation and the binomial tree method is proposed for the multi-stage wind farm with multiple uncertain factors. The solving steps of the proposed model are illustrated with an example and results are compared with those by NPV method. Results validate the excellence of the proposed method.

  13. 堆石粗粒土多级加荷三轴试验分析%MULTI-STAGE LOADING TRIAXIAL TEST ANALYSIS OF ROCK-FILL COARSE GRAINED SOIL

    Institute of Scientific and Technical Information of China (English)

    李远贤; 梁军

    2001-01-01

    通过分析堆石粗粒土一个试样多级加荷三轴试验方法,将其分为不固结类的连续与固结类的不连续加荷。前者仅适用于σ3≤1.2MPa的低围压,后者必须考虑固结排水引起的应力回弹量。不连续加荷的固结方式对强度指标的影响仅限于C值,内摩擦角Φ值基本保持不变。建议对土工试验规程中有关粗粒土的多级加荷三轴试验作重新修订。%On the basis of one sample multi-stage loading triaxial testanalysis of rock-fill coarse grained soil, the loading is divided into unconsolidated type continuous loading and consolidated type discontinuous loading. The former only applies to low wallrock pressure of σ3≤1.2 MPa, and the latter must consider rebound quantity induced by consolidation and drain. The strength index effect of consolidation style of discontinuous loading is only limited to the value of C, while the angle of internal friction Φ is kept basically the same. It is suggested that the rules for coarse grained soil multi-stage loading triaxial tests be revised.

  14. Design of a Natural Gas Liquefaction System with Minimum Components

    International Nuclear Information System (INIS)

    In this work an economic method for liquefying natural gas by diminishing its temperature by means of the Joule-Thomson effect is presented.The pressures from and to which the gas must be expanded arose from a thermodynamic calculation optimizing the cost per unit mass of Liquefied Natural Gas LNG).It was determined that the gas should be expanded from 200 atm to 4 atm.This expansion ratio can be used in different scales.Large Scale: liquefaction of gas at well.It takes advantage of the fact that the gas inside the well is stored at high pressure.The gas is expanded in a valve / nozzle and then compressed to the pressure of the local pipeline system.The objective of this project is to export natural gas as LNG, which is transported by ships to the markets of consumption.Using this method of liquefaction, the LNG production levels are limited to a fraction of the production of the well, due to the injection of the un condensed gas into the local pipelines system.Medium Scale: A high pressure pipeline is the source of the gas.The expansion is performed and then the gas is again compressed to the pressure of a lower pressure pipeline into which the gas is injected.The pressure reductions of natural gas are performed nearby big cities.The aim of this project scale is the storage of fuel for gas thermal power plants during periods of low energy consumption for later burning when the resource is limited. Another possibility that offers this size of plant is the transportation of gas to regions where the resource is unavailable.This transportation would be carried out by means of cistern trucks, in the same way that conventional liquid fuels are transported.Small scale: the place of production would be a CNG refueling station. The source of gas is in this case a gas pipeline of urban distribution and the gas should be compressed with the compressor of the refueling station.Compressors have generally low loading factor and the periods of time when they are not producing

  15. 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

  16. Catalytic processes towards the production of biofuels in a palm oil and oil palm biomass-based biorefinery.

    Science.gov (United States)

    Chew, Thiam Leng; Bhatia, Subhash

    2008-11-01

    In Malaysia, there has been interest in the utilization of palm oil and oil palm biomass for the production of environmental friendly biofuels. A biorefinery based on palm oil and oil palm biomass for the production of biofuels has been proposed. The catalytic technology plays major role in the different processing stages in a biorefinery for the production of liquid as well as gaseous biofuels. There are number of challenges to find suitable catalytic technology to be used in a typical biorefinery. These challenges include (1) economic barriers, (2) catalysts that facilitate highly selective conversion of substrate to desired products and (3) the issues related to design, operation and control of catalytic reactor. Therefore, the catalytic technology is one of the critical factors that control the successful operation of biorefinery. There are number of catalytic processes in a biorefinery which convert the renewable feedstocks into the desired biofuels. These include biodiesel production from palm oil, catalytic cracking of palm oil for the production of biofuels, the production of hydrogen as well as syngas from biomass gasification, Fischer-Tropsch synthesis (FTS) for the conversion of syngas into liquid fuels and upgrading of liquid/gas fuels obtained from liquefaction/pyrolysis of biomass. The selection of catalysts for these processes is essential in determining the product distribution (olefins, paraffins and oxygenated products). The integration of catalytic technology with compatible separation processes is a key challenge for biorefinery operation from the economic point of view. This paper focuses on different types of catalysts and their role in the catalytic processes for the production of biofuels in a typical palm oil and oil palm biomass-based biorefinery. PMID:18434141

  17. Novel Catalytic Membrane Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Nemser, PhD

    2010-10-01

    There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

  18. Paleoseismic investigations in the Kopili Fault Zone of North East India: Evidences from liquefaction chronology

    Science.gov (United States)

    Kumar, Devender; Reddy, D. V.; Pandey, Anand K.

    2016-04-01

    We report the seismogenic liquefaction signatures observed in the Kopili Fault Zone of the Brahmaputra plains, NE India. This seismically active zone has previously been identified as the "Assam seismic gap" and thus necessitates understanding its past seismicity and implied seismic hazard. With this objective, paleo-seismic studies using seismogenic liquefaction features have been carried out in this region largely covered with the flood plain deposits of Kopili and Kalang rivers. The trenches excavated at two locations revealed extensive liquefaction features with more than 20 sub parallel sand dykes having major orientation in NE-SW direction. A total of 29 samples from marker horizons have been processed to constrain chronology of the liquefaction features using optically stimulated luminescence (OSL) and 14C (AMS) dating techniques. The age constraints in terms of respective lower and upper bound age brackets for individual dykes suggest three time intervals of their formations i.e. (i) 250 ± 25 yr. BP, (ii) between 400 to 770 yr. BP and (iii) 900 ± 50 yr. BP. These new ages of liquefaction features correspond to the occurrence timings of causative seismic events which are in addition to the known historical earthquakes and thus enhance our understanding of the paleoseismic history of this region during past ~ 1000 years.

  19. Hydrocarbon liquefaction: viability as a peak oil mitigation strategy.

    Science.gov (United States)

    Höök, Mikael; Fantazzini, Dean; Angelantoni, André; Snowden, Simon

    2014-01-13

    Current world capacity of hydrocarbon liquefaction is around 400,000 barrels per day, providing a marginal share of the global liquid fuel supply. This study performs a broad review of technical, economic, environmental and supply chain issues related to coal-to-liquids (CTL) and gas-to-liquids (GTL). We find three issues predominate. First, significant amounts of coal and gas would be required to obtain anything more than a marginal production of liquids. Second, the economics of CTL plants are clearly prohibitive, but are better for GTL. Nevertheless, large-scale GTL plants still require very high upfront costs, and for three real-world GTL plants out of four, the final cost has been so far approximately three times that initially budgeted. Small-scale GTL holds potential for associated gas. Third, both CTL and GTL incur significant environmental impacts, ranging from increased greenhouse gas emissions (in the case of CTL) to water contamination. Environmental concerns may significantly affect growth of these projects until adequate solutions are found.

  20. HYDROGEN TRANSFER IN CATALYTIC CRACKING

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Hydrogen transfer is an important secondary reaction of catalytic cracking reactions, which affects product yield distribution and product quality. It is an exothermic reaction with low activation energy around 43.3 kJ/mol. Catalyst properties and operation parameters in catalytic cracking greatly influence the hydrogen transfer reaction. Satisfactory results are expected through careful selection of proper catalysts and operation conditions.

  1. 多阶段健康教育在玻璃体视网膜显微手术患者中的应用%Application of multi-stage health education in patients undergoing vitreoretinal microsurgery

    Institute of Scientific and Technical Information of China (English)

    吴欣期; 黄晓薇; 莫丽君; 陈淑怡; 蔡惠霞; 朱中窈

    2014-01-01

    目的 探讨有家属参与的多阶段健康教育在玻璃体视网膜显微手术患者中的应用.方法 将46例玻璃体视网膜显微手术患者随机分为干预组与对照组各23例,对照组给予常规护理,干预组则接受家属共同参与的多阶段健康教育干预方案,记录术后第1天患者一次体位持续时间、不适症状、住院天数及随访资料等,综合以上资料进行评价.结果 干预组在掌握疾病相关知识和技能、对健康教育满意度方面明显优于对照组(P=0.0093,0.0155,0.0019);干预组一次体位维持时间为(170.3±25.5) min,对照组为(91.5±24.9) min,干预组住院天数为(8.3±1.6)d,对照组为(10.2±2.2)d;同时发现干预组与对照组相比,患者不适症状如颈肩不适、胸部不适、下肢麻木明显减少(P=0.0000,0.0011,0.0001).结论 对玻璃体视网膜显微手术患者实施由家属共同参与的多阶段健康教育,可显著提高患者对疾病相关知识的掌握,提高遵医行为,提高医疗护理质量.%Objective To explore the influence and application value of multi-stage health education with family members participating in patients undergoing vitreoretinal microsurgery.Methods 46 patients undergoing vitreoretinal microsurgery were randomly divided into treatment group and control group,23 cases in each group.The control group was given conventional nursing,While the treatment group was given the multi-stage health education with family members participating.By recording the information of lasting time of first body position,symptoms,hospital stays,and follow-up,the research was applied.Results The treatment group was superior to the control group in understanding the related knowledge (P=0.0093) and skills (P=0.0155) of the diseases,shortening hospital stays (P=0.0013),alleviating symptoms and keep the better body position of post operation (P=0.0000).Conclusion Family members participating in multi-stage health education in patients

  2. 多级叶盘结构随机失谐响应特性分析%Mistuned forced response characteristics analysis of mistuned multi-stages bladed disks

    Institute of Scientific and Technical Information of China (English)

    廖海涛; 王建军; 李其汉

    2011-01-01

    为研究多级叶盘结构最大失谐强迫响应幅值及最坏失谐模式,通过没置失谐变量为优化变量,提出了运用遗传算法和序列二次规划混合方法确定最大的失谐强迫响应幅值及最坏失谐模式的通用方法.针对典型三自由度扇区单级和耦合两级叶盘结构集中参数模型计算了相应谐凋系统叶片刚度失谐时的最大失谐幅值放大系数及最坏失谐模式,揭示了失谐跳变-局部化现象,通过算例说明在失谐跳变的叶片位置,叶片出现了强烈的振动响应局部化,构建了与振动响应局部化直接关联的表达因素.运用提出的方法分析了三自由度扇区单级叶盘集中参数模型谐调系统叶片刚度失谐时的敏感度特性,研究表明,随着失谐强度的增加,最大幅值放大系数逐渐增大,并在失谐强度上界处取得极值,并没有所谓的失谐"阈值"现象.%The worst mistuning pattern and robust maximum mistuned forced response of a mistuned multi-stages bladed rotor were studied as an optimization problem. Simulations were carried out on both a lumped parameter model and a disk model with blades simplified as three-degrees-of-freedom substructures. The results of the optimum search of the worst-case mistuning patterns for the lumped parameter model were analyzed, which reveals that the maximum forced response of blade in a mistuned bladed disk is associated with mistuning jump which causes strong localization of the vibration response on a particular blade. The three-degrees-of-freedom per blade disk model was also used for calculation of the maximum forced resonant response of mistuned assemblies and for determination of its sensitivity coefficients with respect to mistuning variation. The studies show that there is no threshold of mistuning beyond which the maximum forced response levels off, or even drops, as the degree of mistuning is increased further. The maximum amplitude magnification of forced response

  3. Soil liquefaction issues at mining dumps at the Lausitz; Bodenverfluessigungsprobleme bei Bergbaukippen in der Lausitz

    Energy Technology Data Exchange (ETDEWEB)

    Kudla, Wolfram [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Bergbau und Spezialtiefbau; Weissbach, Joerg; Szczyrba, Sebastian [Technische Univ. Bergakademie Freiberg (Germany)

    2012-11-01

    For more than 100 years in the Lausitz brown coal is dismantled in open-cast mining. During this time, land with an ara of several 100 km{sup 2} was left as a dump or open-cast mining lakes. These areas are redeveloped by the Lausitz and Central-German Mining Administration Company (Senftenberg, Federal Republic of Germany). The authors of the contribution under consideration report on soil liquefaction issues in mining dumps in the Lausitz. This contribution focuses on a renovation to prevent the sudden transitions from a solid to a liquefied state since 1990 as well as on soil liquefaction on interior dumps at Lausitz. Furthermore, the reasons of the increase in soil pore water pressure and the boundary conditions for liquefaction are described.

  4. Liquefaction hazard mapping with LPI in the Greater Oakland, California, area

    Science.gov (United States)

    Holzer, T.L.; Bennett, M.J.; Noce, T.E.; Padovani, A.C.; Tinsley, J. C., III

    2006-01-01

    Cumulative frequency distributions of the liquefaction potential index (LPI) of surficial geologic units were used to define the liquefaction hazard in a 140-km2 area along the eastern shore of San Francisco Bay near Oakland, California. LPI values were computed for 202 cone penetration tests conducted in surficial geologic units in the study area. The hazard of each unit was defined by the cumulative frequency at LPI = 5. The distributions predict that 73% and 3%, respectively, of the area underlain by artificial fill and Holocene alluvial fan deposits will show surface manifestations of liquefaction during a M7.1 earthquake on the nearby Hayward Fault. The predictions are consistent with recent earthquakes in other areas where similar types of deposits experienced near-field ground motion. ?? 2006, Earthquake Engineering Research Institute.

  5. Research on the direct liquefaction of peat at the Technical Research Centre of Finland (VTT). [Peat

    Energy Technology Data Exchange (ETDEWEB)

    McKeough, P.; Solantausta, Y.

    1985-01-01

    At the Laboratory of Fuel Processing and Lubrication Technology, VTT, a process for the high-pressure liquefaction of peat into motor fuels is being developed. Because the different process steps are strongly interrelated, the production chain has to be optimized as a whole. The optimization is based on the results of both experimential investigations and techno-economic studies. To this date the research has concentrated on a process concept, where dry peat (10% moisture) is fed to the reactor as a slurry with recycle oil from the process. Promising results have been obtained in both experiments and economic evaluations of the process. Research on liquefaction via flash pyrolysis has also been initiated. In addition the Laboratory has participated in an International Energy Agency (IEA) co-operative project where several biomass liquefaction processes were examined.

  6. Hydrothermal liquefaction of Spirulina and Nannochloropsis Salina under subcritical and supercritical water conditions

    DEFF Research Database (Denmark)

    Toor, Saqib; Reddy, H.; Deng, S.;

    2013-01-01

    Six hydrothermal liquefaction experiments on Nannochloropsis salina and Spirulina platensis at subcritical and supercritical water conditions (220-375 °C, 20-255 bar) were carried out to explore the feasibility of extracting lipids from wet algae, preserving nutrients in lipid-extracted algae solid...... residue, and recycling process water for algae cultivation. GC-MS, elemental analyzer, FT-IR, 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-crude yield of 46% was obtained...... on Nannochloropsis salina at 350 °C and 175 bar. For Spirulina platensis algae sample, the optimal hydrothermal liquefaction condition appears to be at 310 °C and 115 bar, while the optimal condition for Nannochloropsis salina is at 350 °C and 175 bar. Preliminary data also indicate that a lipid-extracted algae...

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

    Institute of Scientific and Technical Information of China (English)

    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 lique-faction conditions, including glycerol/methanol ratio, liq-uefaction temperature, and reaction time on the conversion yield. The optimal liquefaction conditions were under the temperature of 120 °C, the reaction time of 7 min, the glycerol–methanol–bamboo ratio of 8/0/2 (W/W), and the microwave power of 300 W. Maximum conversion yield was 96.7%. The liquid products were separated into two contents (water soluble part and precipitate part) by addi-tion of a sufficient amount of water. By Fourier transform infrared (FT-IR), the water soluble content mainly con-tained glycerol and its derivate and carbohydrate degra-dation products, and the precipitate content was mainly lignin derivatives.

  8. Liquefaction and FTIR analysis of two desert shrubs Salix psammophila and Caragana intermedia

    Institute of Scientific and Technical Information of China (English)

    Zhang Chen-xia; Huang Jin-tian

    2006-01-01

    In order to extend the investigation of the characteristics of desert shrub liquefaction and the structure of liquefied desert shrubs, we studied the liquefaction of Salixpsammophila and Caragana intermedia in the presence of phenol and used FTIR analysis on unliquefied and liquefied S. psammophila and C. intermedia. The results showed that the liquefaction effects are enhanced with an increase in temperature, catalyst content and liquid ratio. FTIR analysis proved that more active functional groups appeared after S.psammophila and C. intermedia were liquefied in the presence of phenol. These results can provide a theoretical basis for the further utilization of liquefied S. psammophila and C. intermedia and the development of desert shrubs in a new utilization field.

  9. Soil liquefaction testing and evaluation for Kozloduy nuclear power plant units 5 and 6. Final report

    International Nuclear Information System (INIS)

    In the frame of seismic evaluation of the Kozloduy nuclear power plant units 5 and 6, the region of the spray ponds was investigated because they are of great importance for proper functioning of the NPP in case of an accident. Spray pond is a water containing structure designed for creating a temperature drop of the circulating cooling water in case of an accident in the technical water supply. The region of the spray ponds is well studied in regard to geology and this enabled full-size investigation of the on the liquefaction potential of water saturated sands. In this In this study, three kinds of procedures were applied for estimating the liquefaction potential of water saturated sands. The results obtained were compared, analyzed and conclusions concerning liquefaction potential of water saturated sands drawn

  10. 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.)

  11. 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.

  12. Scenarios Susceptible to Induced Liquefaction Caused by High Magnitude Earthquakes in Santiago de Cuba

    Directory of Open Access Journals (Sweden)

    Liuska Fernández-Diéguez

    2016-05-01

    Full Text Available The objective of this investigation was to define the zoning of soil liquefaction potential for the Guillermón Moncada Popular Council in the municipality of Santiago de Cuba. The engineering and geological conditions and seismic peculiarities favoring a seism to take place were assessed. The safety factor was re-calculated after determining possible maximum intensity values based on seismic magnitudes that can trigger the soil of the investigated area to liquefy. A scheme of the area´s soil susceptibility to liquefaction was obtained. Based on this result, it was concluded that the sectors that are most likely to experience soil liquefaction if an earthquake of magnitudes ranging between 7,75 and 8 occurs are located towards the center-east of the Popular Council with sandy-clayey soils being predominant. This information is very useful for the location and planning of engineering construction works in the area.

  13. Physical modeling and visualization of soil liquefaction under high confining stress

    Institute of Scientific and Technical Information of China (English)

    Lenart González; Tarek Abdoun; Mourad Zeghal; Vivian Kallou; Michael K. Sharp

    2005-01-01

    The mechanisms of seismically-induced liquefaction of granular soils under high confining stresses are still not fully understood. Evaluation of these mechanisms is generally based on extrapolation of observed behavior at shallow depths.Three centrifuge model tests were conducted at RPI's experimental facility to investigate the effects of confining stresses on the dynamic response ora deep horizontal deposit of saturated sand. Liquefaction was observed at high confining stresses in each of the tests. A system identification procedure was used to estimate the associated shear strain and stress time histories.These histories revealed a response marked by shear strength degradation and dilative patterns. The recorded accelerations and pore pressures were employed to generate visual animations of the models. These visualizations revealed a liquefaction front traveling downward and leading to large shear strains and isolation of upper soil layers.

  14. Bifunctional catalytic electrode

    Science.gov (United States)

    Cisar, Alan (Inventor); Murphy, Oliver J. (Inventor); Clarke, Eric (Inventor)

    2005-01-01

    The present invention relates to an oxygen electrode for a unitized regenerative hydrogen-oxygen fuel cell and the unitized regenerative fuel cell having the oxygen electrode. The oxygen electrode contains components electrocatalytically active for the evolution of oxygen from water and the reduction of oxygen to water, and has a structure that supports the flow of both water and gases between the catalytically active surface and a flow field or electrode chamber for bulk flow of the fluids. The electrode has an electrocatalyst layer and a diffusion backing layer interspersed with hydrophilic and hydrophobic regions. The diffusion backing layer consists of a metal core having gas diffusion structures bonded to the metal core.

  15. Catalytic quantum error correction

    CERN Document Server

    Brun, T; Hsieh, M H; Brun, Todd; Devetak, Igor; Hsieh, Min-Hsiu

    2006-01-01

    We develop the theory of entanglement-assisted quantum error correcting (EAQEC) codes, a generalization of the stabilizer formalism to the setting in which the sender and receiver have access to pre-shared entanglement. Conventional stabilizer codes are equivalent to dual-containing symplectic codes. In contrast, EAQEC codes do not require the dual-containing condition, which greatly simplifies their construction. We show how any quaternary classical code can be made into a EAQEC code. In particular, efficient modern codes, like LDPC codes, which attain the Shannon capacity, can be made into EAQEC codes attaining the hashing bound. In a quantum computation setting, EAQEC codes give rise to catalytic quantum codes which maintain a region of inherited noiseless qubits. We also give an alternative construction of EAQEC codes by making classical entanglement assisted codes coherent.

  16. Catalytic Combustion of Gasified Waste

    Energy Technology Data Exchange (ETDEWEB)

    Kusar, Henrik

    2003-09-01

    This thesis concerns catalytic combustion for gas turbine application using a low heating-value (LHV) gas, derived from gasified waste. The main research in catalytic combustion focuses on methane as fuel, but an increasing interest is directed towards catalytic combustion of LHV fuels. This thesis shows that it is possible to catalytically combust a LHV gas and to oxidize fuel-bound nitrogen (NH{sub 3}) directly into N{sub 2} without forming NO{sub x} The first part of the thesis gives a background to the system. It defines waste, shortly describes gasification and more thoroughly catalytic combustion. The second part of the present thesis, paper I, concerns the development and testing of potential catalysts for catalytic combustion of LHV gases. The objective of this work was to investigate the possibility to use a stable metal oxide instead of noble metals as ignition catalyst and at the same time reduce the formation of NO{sub x} In paper II pilot-scale tests were carried out to prove the potential of catalytic combustion using real gasified waste and to compare with the results obtained in laboratory scale using a synthetic gas simulating gasified waste. In paper III, selective catalytic oxidation for decreasing the NO{sub x} formation from fuel-bound nitrogen was examined using two different approaches: fuel-lean and fuel-rich conditions. Finally, the last part of the thesis deals with deactivation of catalysts. The various deactivation processes which may affect high-temperature catalytic combustion are reviewed in paper IV. In paper V the poisoning effect of low amounts of sulfur was studied; various metal oxides as well as supported palladium and platinum catalysts were used as catalysts for combustion of a synthetic gas. In conclusion, with the results obtained in this thesis it would be possible to compose a working catalytic system for gas turbine application using a LHV gas.

  17. 多阶段多目标洗钱网络路径优化模型及算法研究%Multi-stage and Multi-object Optimization Model for Money Laundering Network Path and Its Arithmetic Study

    Institute of Scientific and Technical Information of China (English)

    张艳; 薛耀文

    2016-01-01

    In view of the multi-stage laundering money transfer path optimization decision problems,this paper proposes a multi-stage dynamic path planning model with the maximized amount of money-laundering and minimized risk as the decisionmaking goal on the condition of time pressure.Furthermore,this paper also puts forward an algorithm of solving the model by using the theory of multiple dynamic programming method and the maximum flow algorithm.Finally,the feasibility of the arithmetic has been proved by an example of the algorithm.This model can not only find the characteristic of money laundering behavior from laundering money transfer path,but also discover and track money laundering trails and the entire process,contributing to monitoring effectively all aspects of the money laundering process and reducing the cost of money laundering detection.%针对多阶段洗钱资金转移路径的决策问题,基于多目标优化的思想,构建了以时间约束、总体资金转移量尽可能大以及总体风险尽可能小为决策目标的多阶段洗钱路径优化模型,并利用多重动态规划方法和最大流理论给出了求解该模型的算法,最后通过实例应用验证了该算法的可行性.通过该模型,不仅能够从洗钱资金转移路径观察洗钱行为特征,还能够发现和追踪到洗钱者的洗钱踪迹和全过程,有助于对洗钱行为的各个环节进行有效监控,降低反洗钱侦测成本.

  18. Multi-stage Multi-Channel Percutaneous Nephrolithotomy Treatment Complete Staghorn Calculi%多期多通道经皮肾镜取石术治疗完全性鹿角形结石

    Institute of Scientific and Technical Information of China (English)

    段建军; 燕东亮; 王彭; 张建军

    2015-01-01

    目的 研究多期多通道经皮肾镜取石术( PNL )治疗完全性鹿角形结石的安全性及有效性. 方法 回顾性分析了本院2012年3月至2014年9月接受PNL治疗的完全性鹿角形肾结石患者的临床资料,共35例,双侧鹿角形结石5例,单侧30例,鹿角形结石共40枚. 结果 40枚完全性鹿角形结石共穿刺126条通道,平均3 .15条/枚. 共行PNL术85期,平均2 .1期/枚. 手术时间76~260分钟,平均(96.2 ±14.5)分钟. 结石清除率87.5%. 输血2例,胸膜损伤1例,无其他严重并发症. 术后平均住院时间(7.8+1.21)天. 结论 多期多通道经皮肾镜取石术治疗鹿角形结石安全可行,疗效确切,具有创伤小、恢复快、可反复操作等优点.%Objective To assess the safety and the curative effect of treatment with multi-stage multi -channel percutaneous nephrolithotomy (PNL) in complete staghorn calculi.Methods Retrospective analysis in Mar 2012 to Sep 2014 by the method of treatment 35 patients with complete staghorn calculi ,of whom five had bilateral stones.Results 40 stones were built 126 tracts, the average being 3.15.85 stages were performed, the average being 2.1.The mean ( ±SD) operating time was (96.2 ±24.9) minutes, the stone-free rate was 87.5%, blood transfusions 2, membrane hazard 1, no other complications.Mean ( ±SD) postoperative hospital stay was (7.8+1.21) days.Conclusions Multi-stage multi-channel percutaneous nephrolithotomy treatment complete staghorn calculi is safe and effective .It may offer advantages with respect to less intraoperative and postoperative complications, less invasion and easy recovery.

  19. MULTI-STAGE HYDROPYROLYSIS OF COAL(Ⅱ) ANALYSIS OF TARS%煤多段加氢热解过程的研究(Ⅱ)焦油组成分析

    Institute of Scientific and Technical Information of China (English)

    王娜; 李文; 李保庆

    2001-01-01

    The main components and relative contents of tars obtained in multi-stage hydropyrolysis(M-HyPy) of Xianfeng lignite were analyzed by GC-MS and compared with those in traditional single-stage hydropyrolysis (HyPy).The mechanism of formation of light-end products during M-HyPy was discussed.The results indicated that higher concentration and yields of BTX,PCX and naphthalene were found in M-HyPy as compared to HyPy,which is resulted from promoting hydrogenation and inhibiting repolymerization of free radicals due to the retention of hydrogen in M-HyPy.More light oil was obtained through regulating the reaction conditions,such as increasing pressure and gas flow.The tars produced in multi-stage pyrolysis under syngas were also analyzed.%采用色-质联用技术分析了先锋褐煤多段加氢热解过程中所得焦油的主要组分及其相对含量,并与单段加氢热解过程的结果进行了比较,从中分析了焦油轻质化的机理.结果表明:煤的多段加氢热解过程所得油品与传统的单段加氢热解油品相比,含有更丰富的高经济价值组分,如苯、甲苯、二甲苯和酚、甲酚、二甲酚及萘,这主要是因为氢气在峰温处的停留促进了自由基的氢化饱和及抑制了其再聚合的反应.通过调整反应条件(如增加反应压力、增大氢气流量)可使多段加氢热解过程中所得焦油进一步轻质化.最后,还对合成气气氛下多段热解的油品进行了分析.

  20. SUMMARY REPORT OF THE DOE DIRECT LIQUEFACTION PROCESS DEVELOPMENT CAMPAIGN OF THE LATE TWENTIETH CENTURY

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-07-01

    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.

  1. Numerical computation of anti-liquefaction effect of lattice-type cement-mixed soil countermeasure

    Institute of Scientific and Technical Information of China (English)

    高玉峰; 杨雪玲; 沈扬; 周源

    2008-01-01

    Continuous soil-cement wall confinement method to resist liquefaction is a new kind of process. However, whether it also has a good effect on anti-liquefaction or not needs to be urgently answered for earthquake engineering. Quiet boundary is adopted on the lateral face while free field boundary is employed at the bottom. Byrne model on dynamic pore water pressure generation is accepted and natural seismic wave EI Centro whose peak acceleration is adjusted to 0.2 g in proportion is used for input. A double-layer foundation with sandy soil in the upper portion while clay soil in the lower part is chosen as the calculation model, which is 30 m in length and 20 m in width. The groundwater level is on the ground surface. Excess pore water pressure rate is considered as a liquefaction index in the three-dimensional non-linear earthquake response computation. The anti-liquefaction effectiveness and its influencing factors, such as confinement element area are studied. For the natural double-layer foundation, it is liquefied when the excess pore water pressure rate reaches 1.0 under the seismic load. Under the same earthquake load, the peak excess pore water pressure reduces to 0.56 after adopting reinforcement of the continuous soil-cement wall, which is 46% lower than before. It indicates that continuous soil-cement wall confinement method can attain the purpose of anti-liquefaction. Accordingly, it can be a sort of engineering measure to carry on the anti-liquefaction foundation treatment.

  2. Heterogeneous Catalytic Conversion of Biobased Chemicals into Liquid Fuels in the Aqueous Phase.

    Science.gov (United States)

    Wu, Kejing; Wu, Yulong; Chen, Yu; Chen, Hao; Wang, Jianlong; Yang, Mingde

    2016-06-22

    Different biobased chemicals are produced during the conversion of biomass into fuels through various feasible technologies (e.g., hydrolysis, hydrothermal liquefaction, and pyrolysis). The challenge of transforming these biobased chemicals with high hydrophilicity is ascribed to the high water content of the feedstock and the inevitable formation of water. Therefore, aqueous-phase processing is an interesting technology for the heterogeneous catalytic conversion of biobased chemicals. Different reactions, such as dehydration, isomerization, aldol condensation, ketonization, and hydrogenation, are applied for the conversion of sugars, furfural/hydroxymethylfurfural, acids, phenolics, and so on over heterogeneous catalysts. The activity, stability, and reusability of the heterogeneous catalysts in water are summarized, and deactivation processes and several strategies are introduced to improve the stability of heterogeneous catalysts in the aqueous phase. PMID:27158985

  3. Liquefaction reactivity correlations using pyrolysis/mass spectrometry/pattern recognition procedures

    Energy Technology Data Exchange (ETDEWEB)

    Voorhees, K.J.; Durfee, S.L.; Baldwin, R.M.

    1981-01-01

    In the reported experiments, eleven samples of eastern U.S. coals, have been investigated by pyrolysis/mass spectrometry (Py-MS) pattern recognition procedures to evaluate the feasibility of correlating the observed liquefaction reactivities with the pyrolysis mass spectra. The pyrolyses were conducted in vacuum using a Curie-point pyrolyzer (610/degree/C) coupled directly to the ion source of an Extranuclear SpectrEL mass spectrometer. It is demonstrated by evaluating experimental data that the pyrolysis mass spectra (coal structure parameter) can be correlated with conversion data. This suggests that the structure is the dominant factor in controlling liquefaction properties. 4 refs.

  4. 3rd international conference on coal gasification and liquefaction, University of Pittsburgh

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-01-01

    The third annual international conference on ''Coal Gasification and Liquefaction: What Needs to be Done Now'' was held at the University of Pittsburgh, Pittsburgh, PA on August 3-5, 1976. The majority of the papers dealt with coal gasification and liquefaction (often on the basis of process pilot plant experience) and on flue gas desulfurization by a variety of processes; fewer papers involved fluidized bed combustion, combined cycle power plants, coal desulfurization, government policy on environmental effects and on synthetic fuels, etc. Twenty-eight papers have been entered individually into EDB and ERA. (LTN)

  5. 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

    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...... and exergy destruction than in the baseline cases with compression and injection. Gas liquefaction systems with expansion-based processes are the least performant: the exergy destruction reaches up to 50 MW, and may represent up to 120% of the exergy destruction in the processing plant....

  6. Numerical Simulation of Seabed Response and Liquefaction due to Non-linear Waves

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jin-feng; ZHANG Qing-he; HAN Tao; QIN Chong-ren

    2005-01-01

    Based on Biot's consolidation theory, a two-dimensional model for computation of the seabed response to waves is presented with the finite element method. Numerical results for different wave conditions are obtained, and the effects of wave non-linearity on the wave-induced seabed response are examined. Moreover, the wave-induced momentary liquefaction in uniform and inhomogeneous seabeds is investigated. It is shown that the wave non-linearity affects the distribution of the wave-induced pore pressure and effective stresses, while the influence of wave non-linearity on the seabed liquefaction potential is not so significant.

  7. 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.

  8. Catalyst system and process for benzyl ether fragmentation and coal liquefaction

    Science.gov (United States)

    Zoeller, Joseph Robert

    1998-04-28

    Dibenzyl ether can be readily cleaved to form primarily benzaldehyde and toluene as products, along with minor amounts of bibenzyl and benzyl benzoate, in the presence of a catalyst system comprising a Group 6 metal, preferably molybdenum, a salt, and an organic halide. Although useful synthetically for the cleavage of benzyl ethers, this cleavage also represents a key model reaction for the liquefaction of coal; thus this catalyst system and process should be useful in coal liquefaction with the advantage of operating at significantly lower temperatures and pressures.

  9. Unsteady catalytic processes and sorption-catalytic technologies

    International Nuclear Information System (INIS)

    Catalytic processes that occur under conditions of the targeted unsteady state of the catalyst are considered. The highest efficiency of catalytic processes was found to be ensured by a controlled combination of thermal non-stationarity and unsteady composition of the catalyst surface. The processes based on this principle are analysed, in particular, catalytic selective reduction of nitrogen oxides, deep oxidation of volatile organic impurities, production of sulfur by the Claus process and by hydrogen sulfide decomposition, oxidation of sulfur dioxide, methane steam reforming and anaerobic combustion, selective oxidation of hydrocarbons, etc.

  10. Unsteady catalytic processes and sorption-catalytic technologies

    Energy Technology Data Exchange (ETDEWEB)

    Zagoruiko, A N [G.K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2007-07-31

    Catalytic processes that occur under conditions of the targeted unsteady state of the catalyst are considered. The highest efficiency of catalytic processes was found to be ensured by a controlled combination of thermal non-stationarity and unsteady composition of the catalyst surface. The processes based on this principle are analysed, in particular, catalytic selective reduction of nitrogen oxides, deep oxidation of volatile organic impurities, production of sulfur by the Claus process and by hydrogen sulfide decomposition, oxidation of sulfur dioxide, methane steam reforming and anaerobic combustion, selective oxidation of hydrocarbons, etc.

  11. Cooperative Research Program in Coal-Waste Liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Gerald Huffman

    2000-03-31

    The results of a feasibility study for a demonstration plant for the liquefaction of waste plastic and tires and the coprocessing of these waste polymers with coal are presented. The study was conducted by a committee that included nine representatives from the CFFS, six from the U.S. Department of Energy - Federal Energy Technology Center (FETC), and four from Burns and Roe, Inc. The study included: (1) An assessment of current recycling practices, particularly feedstock recycling in Germany; (2) A review of pertinent research, and a survey of feedstock availability for various types of waste polymers; and (3) A conceptual design for a demonstration plant was developed and an economic analysis for various feedstock mixes. The base case for feedstock scenarios was chosen to be 200 tons per day of waste plastic and 100 tons per day of waste tires. For this base case with oil priced at $20 per barrel, the return on investment (ROI) was found to range from 9% to 20%, using tipping fees for waste plastic and tires typical of those existing in the U.S. The most profitable feedstock appeared to waste plastic alone, with a plant processing 300 t/d of plastic yielding ROI's from 13 to 27 %, depending on the tipping fees for waste plastic. Feedstock recycling of tires was highly dependent on the price that could be obtained for recovered carbon. Addition of even relatively small amounts (20 t/d) of coal to waste plastic and/or coal feeds lowered the ROI's substantially. It should also be noted that increasing the size of the plant significantly improved all ROI's. For example, increasing plant size from 300 t/d to1200 t/d approximately doubles the estimated ROI's for a waste plastic feedstock.

  12. 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.

  13. Constrained Optimization Evolutionary Algorithm Combining Non-stationary Multi-stage Penalty Function%结合非固定多段罚函数的约束优化进化算法

    Institute of Scientific and Technical Information of China (English)

    邹木春

    2012-01-01

    利用非固定多段映射罚函数的约束条件,提出一种结合非固定多段罚函数的约束优化进化算法.该算法利用佳点集方法初始化种群,以保证其均匀分布在搜索空间中.在进化过程中,对种群进行单形交叉和多样性变异操作产生新的个体,增加种群的多样性.对6个经典Benchmark问题进行测试,实验结果表明,该算法能有效地处理不同的约束优化问题.%Using non-stationary multi-stage assignment penalty function to deal with the constrained conditions, a modified constrained optimization evolutionary algorithm is proposed. In the process of evolution, in order to ensure the population evenly distributed in the search space, the individuals generation based on good point set method is introduced into the evolutionary algorithm initial step. The offspring population individuals are generated by simplex crossover and diversity mutation operator to maintain the diversity of population. Six classic Benchmark problems are tested. Experimental results show that the proposed algorithm is an effective way for constrained optimization problems.

  14. Analysis on Cavitation Performance in Multi-stage Centrifugal Pump Based on Cavitation Model%基于空化模型的多级离心泵汽蚀性能分析

    Institute of Scientific and Technical Information of China (English)

    黄思; 管俊

    2011-01-01

    A cavitation analysis model for centrifugal pump is developed based on the Rayleigh-Plesset bubble equation.The 3D turbulent flow field and gas-liquid phase distribution in a multi-stage centrifugal pump are computed by solving the bubble equation coupled with two-phase turbulent governing equations.The process of bubble vaporization, growing and condensation are simulated and visualized.The cavitation model and simulation are validated by comparing numerical solutions with tested curve of Q-NPSHr for the pump.%应用Rayleigh-Plesset气泡方程建立离心泵空化模型,并与气液两相湍流控制方程耦合求解,得到了多级离心泵内三维湍流场及气液相分布,捕捉到气泡的初生、发展及冷凝过程.计算了不同流量下的离心泵的必需汽蚀余量并与实测结果进行了对比分析.

  15. Catalytic production of biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Theilgaard Madsen, A.

    2011-07-01

    The focus of this thesis is the catalytic production of diesel from biomass, especially emphasising catalytic conversion of waste vegetable oils and fats. In chapter 1 an introduction to biofuels and a review on different catalytic methods for diesel production from biomass is given. Two of these methods have been used industrially for a number of years already, namely the transesterification (and esterification) of oils and fats with methanol to form fatty acid methyl esters (FAME), and the hydrodeoxygenation (HDO) of fats and oils to form straight-chain alkanes. Other possible routes to diesel include upgrading and deoxygenation of pyrolysis oils or aqueous sludge wastes, condensations and reductions of sugars in aqueous phase (aqueous-phase reforming, APR) for monofunctional hydrocarbons, and gasification of any type of biomass followed by Fischer-Tropsch-synthesis for alkane biofuels. These methods have not yet been industrialised, but may be more promising due to the larger abundance of their potential feedstocks, especially waste feedstocks. Chapter 2 deals with formation of FAME from waste fats and oils. A range of acidic catalysts were tested in a model fat mixture of methanol, lauric acid and trioctanoin. Sulphonic acid-functionalised ionic liquids showed extremely fast convertion of lauric acid to methyl laurate, and trioctanoate was converted to methyl octanoate within 24 h. A catalyst based on a sulphonated carbon-matrix made by pyrolysing (or carbonising) carbohydrates, so-called sulphonated pyrolysed sucrose (SPS), was optimised further. No systematic dependency on pyrolysis and sulphonation conditions could be obtained, however, with respect to esterification activity, but high activity was obtained in the model fat mixture. SPS impregnated on opel-cell Al{sub 2}O{sub 3} and microporous SiO{sub 2} (ISPS) was much less active in the esterification than the original SPS powder due to low loading and thereby low number of strongly acidic sites on the

  16. Techno-Economic Analysis of Liquid Fuel Production from Woody Biomass via Hydrothermal Liquefaction (HTL) and Upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yunhua; Biddy, Mary J.; Jones, Susanne B.; Elliott, Douglas C.; Schmidt, Andrew J.

    2014-09-15

    A series of experimental work was conducted to convert woody biomass to gasoline and diesel range products via hydrothermal liquefaction (HTL) and catalytic hydroprocessing. Based on the best available test data, a techno-economic analysis (TEA) was developed for a large scale woody biomass based HTL and upgrading system to evaluate the feasibility of this technology. In this system, 2000 dry metric ton per day woody biomass was assumed to be converted to bio-oil in hot compressed water and the bio-oil was hydrotreated and/or hydrocracked to produce gasoline and diesel range liquid fuel. Two cases were evaluated: a stage-of-technology (SOT) case based on the tests results, and a goal case considering potential improvements based on the SOT case. Process simulation models were developed and cost analysis was implemented based on the performance results. The major performance results included final products and co-products yields, raw materials consumption, carbon efficiency, and energy efficiency. The overall efficiency (higher heating value basis) was 52% for the SOT case and 66% for the goal case. The production cost, with a 10% internal rate of return and 2007 constant dollars, was estimated to be $1.29 /L for the SOT case and $0.74 /L for the goal case. The cost impacts of major improvements for moving from the SOT to the goal case were evaluated and the assumption of reducing the organics loss to the water phase lead to the biggest reduction in the production cost. Sensitivity analysis indicated that the final products yields had the largest impact on the production cost compared to other parameters. Plant size analysis demonstrated that the process was economically attractive if the woody biomass feed rate was over 1,500 dry tonne/day, the production cost was competitive with the then current petroleum-based gasoline price.

  17. 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.

  18. 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.

  19. Catalytic cracking of lignites

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, M.; Nowak, S.; Naegler, T.; Zimmermann, J. [Hochschule Merseburg (Germany); Welscher, J.; Schwieger, W. [Erlangen-Nuernberg Univ. (Germany); Hahn, T. [Halle-Wittenberg Univ., Halle (Germany)

    2013-11-01

    A most important factor for the chemical industry is the availability of cheap raw materials. As the oil price of crude oil is rising alternative feedstocks like coal are coming into focus. This work, the catalytic cracking of lignite is part of the alliance ibi (innovative Braunkohlenintegration) to use lignite as a raw material to produce chemicals. With this new one step process without an input of external hydrogen, mostly propylene, butenes and aromatics and char are formed. The product yield depends on manifold process parameters. The use of acid catalysts (zeolites like MFI) shows the highest amount of the desired products. Hydrogen rich lignites with a molar H/C ratio of > 1 are to be favoured. Due to primary cracking and secondary reactions the ratio between catalyst and lignite, temperature and residence time are the most important parameter to control the product distribution. Experiments at 500 C in a discontinuous rotary kiln reactor show yields up to 32 wt-% of hydrocarbons per lignite (maf - moisture and ash free) and 43 wt-% char, which can be gasified. Particularly, the yields of propylene and butenes as main products can be enhanced four times to about 8 wt-% by the use of catalysts while the tar yield decreases. In order to develop this innovative process catalyst systems fixed on beads were developed for an easy separation and regeneration of the used catalyst from the formed char. (orig.)

  20. Catalytic Membrane Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, T.J.; Brinker, C.J.; Gardner, T.J.; Hughes, R.C.; Sault, A.G.

    1998-12-01

    The proposed "catalytic membrane sensor" (CMS) was developed to generate a device which would selectively identify a specific reagent in a complex mixture of gases. This was to be accomplished by modifying an existing Hz sensor with a series of thin films. Through selectively sieving the desired component from a complex mixture and identifying it by decomposing it into Hz (and other by-products), a Hz sensor could then be used to detect the presence of the select component. The proposed "sandwich-type" modifications involved the deposition of a catalyst layered between two size selective sol-gel layers on a Pd/Ni resistive Hz sensor. The role of the catalyst was to convert organic materials to Hz and organic by-products. The role of the membraneo was to impart both chemical specificity by molecukir sieving of the analyte and converted product streams, as well as controlling access to the underlying Pd/Ni sensor. Ultimately, an array of these CMS elements encompassing different catalysts and membranes were to be developed which would enable improved selectivity and specificity from a compiex mixture of organic gases via pattern recognition methodologies. We have successfully generated a CMS device by a series of spin-coat deposited methods; however, it was determined that the high temperature required to activate the catalyst, destroys the sensor.