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Sample records for amoco sulfur recovery process

  1. Large-plant sulfur recovery processes stress efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Goar, B.G.; Nasato, E. (Goar, Allison Associates Inc., Tyler, TX (United States))

    1994-05-23

    Natural-gas processing in the future will encounter significantly more raw sour gas, i.e., gas containing 15--20 mol % H[sub 2]S or greater. Deciding whether to make the significant investment to build a sour-gas treating and sulfur-recovery plant involves many considerations. An operator selecting the optimum gas treating, sulfur recovery, and tail-gas cleanup processes must choose each carefully because each upstream step can affect design and operation of subsequent downstream steps. Reviewed here are current gas treating and sulfur-recovery processes in use today. For this purpose, plants that process sour gas and recover 50 long tons/day (ltd) or more of sulfur will be considered. Sample plants employing major technologies are listed in a table. Such other sulfur recovery, removal processes as Lo-Cat, SulFerox, Stretford, Iron Sponge, SulfaTreat, and Sulfa-Scrub are available to industry. But these processes are normally considered only when the total sulfur to be handled is 15--20 ltd or less. Additionally, many are troublesome to operate and have relatively high operating costs.

  2. HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

    Energy Technology Data Exchange (ETDEWEB)

    Dennis Dalrymple

    2004-06-01

    This final report describes the objectives, technical approach, results and conclusions for a project funded by the U.S. Department of Energy to test a hybrid sulfur recovery process for natural gas upgrading. The process concept is a configuration of CrystaTech, Inc.'s CrystaSulf{reg_sign} process which utilizes a direct oxidation catalyst upstream of the absorber tower to oxidize a portion of the inlet hydrogen sulfide (H{sub 2}S) to sulfur dioxide (SO{sub 2}) and elemental sulfur. This hybrid configuration of CrystaSulf has been named CrystaSulf-DO and represents a low-cost option for direct treatment of natural gas streams to remove H{sub 2}S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day and more. This hybrid process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both onshore and offshore applications. CrystaSulf is a nonaqueous sulfur recovery process that removes H{sub 2}S from gas streams and converts it to elemental sulfur. In CrystaSulf, H{sub 2}S in the inlet gas is reacted with SO{sub 2} to make elemental sulfur according to the liquid phase Claus reaction: 2H{sub 2}S + SO{sub 2} {yields} 2H{sub 2}O + 3S. The SO{sub 2} for the reaction can be supplied from external sources by purchasing liquid SO{sub 2} and injecting it into the CrystaSulf solution, or produced internally by converting a portion of the inlet gas H{sub 2}S to SO{sub 2} or by burning a portion of the sulfur produced to make SO{sub 2}. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, the needed SO{sub 2} is produced by placing a bed of direct oxidation catalyst in the inlet gas stream to oxidize

  3. Performance and cost models for the direct sulfur recovery process. Task 1 Topical report, Volume 3

    Energy Technology Data Exchange (ETDEWEB)

    Frey, H.C. [North Carolina State Univ., Raleigh, NC (United States); Williams, R.B. [Carneigie Mellon Univ., Pittsburgh, PA (United States)

    1995-09-01

    The purpose of this project is to develop performance and cost models of the Direct Sulfur Recovery Process (DSRP). The DSRP is an emerging technology for sulfur recovery from advanced power generation technologies such as Integrated Gasification Combined Cycle (IGCC) systems. In IGCC systems, sulfur present in the coal is captured by gas cleanup technologies to avoid creating emissions of sulfur dioxide to the atmosphere. The sulfur that is separated from the coal gas stream must be collected. Leading options for dealing with the sulfur include byproduct recovery as either sulfur or sulfuric acid. Sulfur is a preferred byproduct, because it is easier to handle and therefore does not depend as strongly upon the location of potential customers as is the case for sulfuric acid. This report describes the need for new sulfur recovery technologies.

  4. Commercial Application of the RAR Sulfur Recovery and Tail Gas Treating Process

    Institute of Scientific and Technical Information of China (English)

    Guo Hong; Zhang Songping

    2003-01-01

    The 40kt/a sulfur recovery unit for tail gas treating applying the reduction-absorption-recycling (RAR) technology is aimed at regeneration of the rich amine solution and recovery of sulfur to operate in tandem with the 1.2Mt/a diesel hydrofining unit. The process unit calibration data have revealed that the recovery of total sulfur reaches 99.86%, which is 6.65 percentage points higher than that before application of the RAR technology. The SO2 content in vented tail gas is 0.27 t/d, which is much less than the latest emission standard prescribed by the State. The factors that can affect the unit operation have been analyzed and corresponding measures have been suggested including the necessity to improve the control over the reaction temperature in the tail gas hydrogenation unit.

  5. HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING LAST TECHNICAL REPORT BEFORE NOVATION FROM URS CORP. TO CRYSTATECH, INC

    International Nuclear Information System (INIS)

    This project was funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H(sub 2)S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both on-shore and offshore applications. CrystaSulf (service mark of Gas Research Institute) is a new nonaqueous sulfur recovery process that removes hydrogen sulfide (H(sub 2)S) from gas streams and converts it into elemental sulfur. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, approximately 1/3 of the total H(sub 2)S in the natural gas is first oxidized to SO(sub 2) at low temperatures over a heterogeneous catalyst. Low temperature oxidation is done so that the H(sub 2)S can be oxidized in the presence of methane while avoiding methane oxidation. The project involved the development of a detailed plan for laboratory and bench scale-up application, laboratory/bench-scale catalyst testing, and demonstration of scale-up economic advantages. The bench-scale tests examined two different catalysts that are promoted modifications of TDA's patented partial oxidation catalyst used to make elemental sulfur. The experiments showed that catalyst TDA No.2 is superior for use with the hybrid CrystaSulf process in that much higher yields of SO(sub 2) can be obtained. Continued testing is planned

  6. Desulfurisation and sulfur recovery

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, P.; Finn, A.; Scott, L. [Costain Oil, Gas and Process Ltd (United Kingdom)

    2001-09-01

    This article highlights technical issues associated with different sulphur recovery processes in the hydrocarbon processing industry. Details are given of the Stretford process developed by British Gas for the removal of low concentrations of hydrogen sulphide from natural gas and other hydrocarbon gases; the SulFerox process developed by Shell and Dow for removing moderate amounts of sulphur from contaminated gases using a proprietary iron salt for extracting the sulphur; solvent systems for removing moderately high concentrations of hydrogen sulphide in sour gas or liquid petroleum gases (LPG); the simple Claus process involving the partial combustion of hydrogen sulphide forming sulphur dioxide which reacts with hydrogen sulphide to form sulphur; and enhanced Claus processes. Sour water stripping processes for hydrogen sulphide contaminated water from hydrocarbon processing, tail gas treatment of Claus plant offgases, and hydrotreating are also discussed.

  7. Surface acoustic wave sensors/gas chromatography; and Low quality natural gas sulfur removal and recovery CNG Claus sulfur recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Klint, B.W.; Dale, P.R.; Stephenson, C.

    1997-12-01

    This topical report consists of the two titled projects. Surface Acoustic Wave/Gas Chromatography (SAW/GC) provides a cost-effective system for collecting real-time field screening data for characterization of vapor streams contaminated with volatile organic compounds (VOCs). The Model 4100 can be used in a field screening mode to produce chromatograms in 10 seconds. This capability will allow a project manager to make immediate decisions and to avoid the long delays and high costs associated with analysis by off-site analytical laboratories. The Model 4100 is currently under evaluation by the California Environmental Protection Agency Technology Certification Program. Initial certification focuses upon the following organics: cis-dichloroethylene, chloroform, carbon tetrachloride, trichlorethylene, tetrachloroethylene, tetrachloroethane, benzene, ethylbenzene, toluene, and o-xylene. In the second study the CNG Claus process is being evaluated for conversion and recovery of elemental sulfur from hydrogen sulfide, especially found in low quality natural gas. This report describes the design, construction and operation of a pilot scale plant built to demonstrate the technical feasibility of the integrated CNG Claus process.

  8. A fuel-cell-assisted iron redox process for simultaneous sulfur recovery and electricity production from synthetic sulfide wastewater

    International Nuclear Information System (INIS)

    Highlights: ► A novel FC-IR process was reported to recover sulfur and electricity from sulfide. ► The fuel cell and iron based liquid redox sulfur recovery techniques were combined. ► The sulfide oxidation and Fe(III) regeneration were individually investigated. ► Results of coupling operation confirmed the feasibility of the FC-IR process. - Abstract: Sulfide present in wastewaters and waste gases should be removed due to its toxicity, corrosivity, and malodorous property. Development of effective, stable, and feasible methods for sulfur recovery from sulfide attains a double objective of waste minimization and resource recovery. Here we report a novel fuel-cell-assisted iron redox (FC-IR) process for simultaneously recovering sulfur and electricity from synthetic sulfide wastewater. The FC-IR system consists of an oxidizing reactor where sulfide is oxidized to elemental sulfur by Fe(III), and a fuel cell where Fe(III) is regenerated from Fe(II) concomitantly with electricity producing. The oxidation of sulfide by Fe(III) is significantly dependent on solution pH. Increasing the pH from 0.88 to 1.96 accelerates the oxidation of sulfide, however, lowers the purity of the produced elemental sulfur. The performance of fuel cell is also a strong function of solution pH. Fe(II) is completely oxidized to Fe(III) when the fuel cell is operated at a pH above 6.0, whereas only partially oxidized below pH 6.0. At pH 6.0, the highest columbic efficiency of 75.7% is achieved and electricity production maintains for the longest time of 106 h. Coupling operation of the FC-IR system obtains sulfide removal efficiency of 99.90%, sulfur recovery efficiency of 78.6 ± 8.3%, and columbic efficiency of 58.6 ± 1.6%, respectively. These results suggest that the FC-IR process is a promising tool to recover sulfur and energy from sulfide.

  9. Improvement on Technology of WSA Sulfur Recovery Process%WSA制酸工艺技术改造

    Institute of Scientific and Technical Information of China (English)

    苗澍; 金淼

    2011-01-01

    丹麦托普索WSA湿法制酸工艺可以有效地利用各种生产过程中产生的含硫酸性气体直接制酸,得到商品级浓硫酸,具有适用范围广、工艺流程简单、硫回收效率高、操作成本低、经济效益好等特点。介绍了唐山佳华煤化工有限公司WSA硫回收工艺的原理、生产运行情况及改造措施。%The Topsoe WSA wet-process acid production process of Denmark may utilize effectively sulfur-containing acid gases from various production processes to manufacture acid directly,and obtain the commercial-grade concentrated sulfuric acid.The technology has the characteristics of large scope of application,simple process flowsheet,high sulfur recovery,low operation cost and good economic benefit.To introduce the principle,producton run and renovation measures of the WSA sulfur recovery process of Tangshan Jiahua Coking and Chemical Co.,Ltd.

  10. Avoiding total reduced sulfur (TRS) emissions from sodium sulfite pulping recovery processes

    International Nuclear Information System (INIS)

    This paper reports that one of the current trends in paper-making with cellulose pulping is the use of high-yield processes. With yields greater than 65%, these processes include mechanical pulps (groundwood and thermomechanical pulps or TMP), and semichemical types (chemi-TMP or CTMP). Groundwood and TMP make up about 10% of North American pulp production. Semichemical pulp makes up about 7% and is mostly used for corrugating medium. High-yield pulping for linerboard, particularly using the alkaline sulfite process, is also likely to be used in the future. High-yield pulping is based primarily on the sulfite process using mostly sodium-based chemicals. A disadvantage of this process is the unavailability of a recovery system for the inorganic pulping chemicals. Generally, mills have not accepted any particular recovery system for this process. For this and other reasons, sulfite processes constitute only 3-4% of the total North American pulp production. If high-yield processes continue to increase in popularity, a sodium sulfite chemical recovery system will be needed. A number of chemical recovery systems have been developed in the past 30 years for sodium-based sulfite pulping processes, with most of the mills successfully using this process located in Scandinavia

  11. Screening study for waste biomass to ethanol production facility using the Amoco process in New York State. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This report evaluates the economic feasibility of locating biomass-to-ethanol waste conversion facilities in New York State. Part 1 of the study evaluates 74 potential sites in New York City and identifies two preferred sites on Staten, the Proctor Gamble and the Arthur Kill sites, for further consideration. Part 2 evaluates upstate New York and determines that four regions surrounding the urban centers of Albany, Buffalo, Rochester, and Syracuse provide suitable areas from which to select specific sites for further consideration. A separate Appendix provides supplemental material supporting the evaluations. A conceptual design and economic viability evaluation were developed for a minimum-size facility capable of processing 500 tons per day (tpd) of biomass consisting of wood or paper, or a combination of the two for upstate regions. The facility would use Amoco`s biomass conversion technology and produce 49,000 gallons per day of ethanol and approximately 300 tpd of lignin solid by-product. For New York City, a 1,000-tpd processing facility was also evaluated to examine effects of economies of scale. The reports evaluate the feasibility of building a biomass conversion facility in terms of city and state economic, environmental, and community factors. Given the data obtained to date, including changing costs for feedstock and ethanol, the project is marginally attractive. A facility should be as large as possible and located in a New York State Economic Development Zone to take advantage of economic incentives. The facility should have on-site oxidation capabilities, which will make it more financially viable given the high cost of energy. 26 figs., 121 tabs.

  12. Electricity generation from iron EDTA-based liquid redox sulfur recovery process with enhanced stability of EDTA

    International Nuclear Information System (INIS)

    Highlights: • A sustainable and stable liquid redox process was proposed to recover electricity and sulfur from waste pollutant H2S. • The fuel cell was employed into iron EDTA-based liquid redox sulfur recovery technique. • The optimal pH, which was turned out to be 9, maximally produced electricity as well as effectively captured H2S. • Fuel cell provides an innovative way to enhance the stability of EDTA. - Abstract: In this study, an innovative iron EDTA-based H2S capture technology was proposed. Just like currently available approaches, this system allows to capture H2S and convert it into element sulfur. It does so, however, with net energy production and without absorbent degradation. The system, consisting of an absorber and a fuel cell units, absorbs gaseous H2S and oxidize it to elemental sulfur in the absorber compartment, and in the fuel cell unit converts the reduced form of the absorbent [Fe(II)EDTA]2− back to [Fe(III)EDTA]−, generating electricity. When solution pH was raised from 7 to 10, more gaseous H2S was absorbed into [Fe(III)EDTA]−, resulting in increased production [Fe(II)EDTA]2−. This reduced form of the absorbent, which should be subsequently regenerated for continuous operation, serves as a fuel in a Fe(II)-based fuel cell. Fuel cell performance was also found to be strongly affected by solution pH, and the highest maximum power density of 0.832 mW cm−2 was achieved at pH 9 and 60 °C. At this condition, more than 80% of [Fe(III)EDTA]− was recovered from [Fe(II)EDTA]2− in 2 h without any noticeable degradation of EDTA, amounted to the oxidation rate of 147 g Fe h−1m−2 anode surface area. This study provides demonstration of many desirable aspects for field implementation, such as electricity generation, sulfur recovery and long-term stability of the absorbent

  13. Corrosion in sulfur recovery units

    Energy Technology Data Exchange (ETDEWEB)

    Fraisse, M.

    1979-06-01

    Corrosion in sulfur recovery units may be caused by sulfuric acid formed at cold points in operating units or during the startup, shutdown, or catalyst regeneration periods. Insufficient high-temperature resistance of main boiler materials to sulfuric acid is another common cause of severe corrosion. The specific corrosion problems encountered in hydrotreating units include high- and low-temperature hydrogen embrittlement of steel above 200/sup 0/C and between -50/sup 0/ and +20/sup 0/C, respectively, sometimes accompanied with blistering; carbon steel corrosion by hydrogen sulfide above 280/sup 0/C in desulfurization units; low-temperature stress corrosion or hydrogen blistering by H/sub 2/S in aqueous environments; corrosion by chloride ions coupled with precipitation of ammonium chloride in catalytic reformers during catalyst regeneration; corrosion and fouling by ammonium sulfide in gas oil hydrodesulfurization units and reformers below 90/sup 0/C; and intergranular and stress corrosion of austenitic steels by polythionic acids which may be formed during startup or catalyst regeneration periods. Methods for preventing these types of corrosion are outlined.

  14. Ion flotation application for rare earths recovery from the products of apatite processing with sulfuric acid

    International Nuclear Information System (INIS)

    The possibility was proved experimentally of ion flotation applicability for REE recovery from phosphogypsum leaching solutions and extractional phosphoric acid. On treating leaching solutions with dialkylphosphoric acids a solid sublate was formed whose extraction degree was as high as 95 %. Treatment of extractional phosphoric acid with alkyl sulfates resulted in twice as high as high REE concentration in foam product that in the residue. 17 refs

  15. Sulfur Recovery from Acid Gas Using the Claus Process and High Temperature Air Combustion (HiTAC Technology

    Directory of Open Access Journals (Sweden)

    Mohamed Sassi

    2008-01-01

    Full Text Available Sulfur-bearing compounds are very detrimental to the environment and to industrial process equipment. They are often obtained or formed as a by-product of separation and thermal processing of fuels containing sulfur, such as coal, crude oil and natural gas. The two sulfur compounds, which need special attention, are: hydrogen sulfide (H2S and sulfur dioxide (SO2. H2S is a highly corrosive gas with a foul smell. SO2 is a toxic gas responsible for acid rain formation and equipment corrosion. Various methods of reducing pollutants containing sulfur are described in this paper, with a focus on the modified Claus process, enhanced by the use of High Temperature Air Combustion (HiTAC technology in the Claus furnace. The Claus process has been known and used in the industry for over 100 years. It involves thermal oxidation of hydrogen sulfide and its reaction with sulfur dioxide to form sulfur and water vapor. This process is equilibrium-limited and usually achieves efficiencies in the range of 94-97%, which have been regarded as acceptable in the past years. Nowadays strict air pollution regulations regarding hydrogen sulfide and sulfur dioxide emissions call for nearly 100% efficiency, which can only be achieved with process modifications. High temperature air combustion technology or otherwise called flameless (or colorless combustion is proposed here for application in Claus furnaces, especially those employing lean acid gas streams, which cannot be burned without the use of auxiliary fuel or oxygen enrichment under standard conditions. With the use of HiTAC it has been shown, however, that fuel-lean, Low Calorific Value (LCV fuels can be burned with very uniform thermal fields without the need for fuel enrichment or oxygen addition. The uniform temperature distribution favors clean and efficient burning with an additional advantage of significant reduction of NOx, CO and hydrocarbon emission.

  16. Amoco Cadiz oil spill

    Energy Technology Data Exchange (ETDEWEB)

    O' Sullivan, A.J.

    1978-05-01

    This report gives a preliminary account of the events surrounding the wreck of the Amoco Cadiz on the Brittany coast in March, which caused the most massive oil pollution on record. The sequence of events is outlined. Also reported are details of clean-up of beaches as well as appearance and biological effects of oil. Further studies which will continue for years include: population dynamics (species of Littorina); feeding, reproduction, settlement of Spirorbis sp; surveillance of echinoderm and crustacean populations; changes in growth and development of species of red algae; changes in concentrations of bacteria, meiofauna, chlorophyll and organic material. There are indications of problems likely to arise in: sheltered areas (sediments, salt marsh vegetation); sandy shores; upper shore vegetation (higher plants, lichens); algae (temporary loss of algal cover); intertidal macrofauna; seabirds (mortality); economy (fishing, tourism, seaweed used for fertilizer).

  17. Screening study for waste biomass to ethanol production facility using the Amoco process in New York State. Appendices to the final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    The final report evaluates the economic feasibility of locating biomass-to-ethanol waste conversion facilities in New York State. Part 1 of the study evaluates 74 potential sites in New York City and identifies two preferred sites on Staten Island, the Proctor and Gamble and the Arthur Kill sites for further consideration. Part 2 evaluates upstate New York and determines that four regions surrounding the urban centers of Albany, Buffalo, Rochester, and Syracuse provide suitable areas from which to select specific sites for further consideration. A conceptual design and economic viability evaluation were developed for a minimum-size facility capable of processing 500 tons per day (tpd) of biomass consisting of wood or paper, or a combination of the two for upstate regions. The facility would use Amoco`s biomass conversion technology and produce 49,000 gallons per day of ethanol and approximately 300 tpd of lignin solid by-product. For New York City, a 1,000-tpd processing facility was also evaluated to examine effects of economies of scale. The reports evaluate the feasibility of building a biomass conversion facility in terms of city and state economic, environmental, and community factors. Given the data obtained to date, including changing costs for feedstock and ethanol, the project is marginally attractive. A facility should be as large as possible and located in a New York State Economic Development Zone to take advantage of economic incentives. The facility should have on-site oxidation capabilities, which will make it more financially viable given the high cost of energy. This appendix to the final report provides supplemental material supporting the evaluations.

  18. Synthesis and development of processes for the recovery of sulfur from acid gases. Part 1, Development of a high-temperature process for removal of H{sub 2}S from coal gas using limestone -- thermodynamic and kinetic considerations; Part 2, Development of a zero-emissions process for recovery of sulfur from acid gas streams

    Energy Technology Data Exchange (ETDEWEB)

    Towler, G.P.; Lynn, S.

    1993-05-01

    Limestone can be used more effectively as a sorbent for H{sub 2}S in high-temperature gas-cleaning applications if it is prevented from undergoing calcination. Sorption of H{sub 2}S by limestone is impeded by sintering of the product CaS layer. Sintering of CaS is catalyzed by CO{sub 2}, but is not affected by N{sub 2} or H{sub 2}. The kinetics of CaS sintering was determined for the temperature range 750--900{degrees}C. When hydrogen sulfide is heated above 600{degrees}C in the presence of carbon dioxide elemental sulfur is formed. The rate-limiting step of elemental sulfur formation is thermal decomposition of H{sub 2}S. Part of the hydrogen thereby produced reacts with CO{sub 2}, forming CO via the water-gas-shift reaction. The equilibrium of H{sub 2}S decomposition is therefore shifted to favor the formation of elemental sulfur. The main byproduct is COS, formed by a reaction between CO{sub 2} and H{sub 2}S that is analogous to the water-gas-shift reaction. Smaller amounts of SO{sub 2} and CS{sub 2} also form. Molybdenum disulfide is a strong catalyst for H{sub 2}S decomposition in the presence of CO{sub 2}. A process for recovery of sulfur from H{sub 2}S using this chemistry is as follows: Hydrogen sulfide is heated in a high-temperature reactor in the presence of CO{sub 2} and a suitable catalyst. The primary products of the overall reaction are S{sub 2}, CO, H{sub 2} and H{sub 2}O. Rapid quenching of the reaction mixture to roughly 600{degrees}C prevents loss Of S{sub 2} during cooling. Carbonyl sulfide is removed from the product gas by hydrolysis back to CO{sub 2} and H{sub 2}S. Unreacted CO{sub 2} and H{sub 2}S are removed from the product gas and recycled to the reactor, leaving a gas consisting chiefly of H{sub 2} and CO, which recovers the hydrogen value from the H{sub 2}S. This process is economically favorable compared to the existing sulfur-recovery technology and allows emissions of sulfur-containing gases to be controlled to very low levels.

  19. ENGINEERING EVALUATION OF HOT-GAS DESULFURIZATION WITH SULFUR RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    G.W. ROBERTS; J.W. PORTZER; S.C. KOZUP; S.K. GANGWAL

    1998-05-31

    Engineering evaluations and economic comparisons of two hot-gas desulfurization (HGD) processes with elemental sulfur recovery, being developed by Research Triangle Institute, are presented. In the first process, known as the Direct Sulfur Recovery Process (DSRP), the SO{sub 2} tail gas from air regeneration of zinc-based HGD sorbent is catalytically reduced to elemental sulfur with high selectivity using a small slipstream of coal gas. DSRP is a highly efficient first-generation process, promising sulfur recoveries as high as 99% in a single reaction stage. In the second process, known as the Advanced Hot Gas Process (AHGP), the zinc-based HGD sorbent is modified with iron so that the iron portion of the sorbent can be regenerated using SO{sub 2} . This is followed by air regeneration to fully regenerate the sorbent and provide the required SO{sub 2} for iron regeneration. This second-generation process uses less coal gas than DSRP. Commercial embodiments of both processes were developed. Process simulations with mass and energy balances were conducted using ASPEN Plus. Results show that AHGP is a more complex process to operate and may require more labor cost than the DSRP. Also capital costs for the AHGP are higher than those for the DSRP. However, annual operating costs for the AHGP appear to be considerably less than those for the DSRP with a potential break-even point between the two processes after just 2 years of operation for an integrated gasification combined cycle (IGCC) power plant using 3 to 5 wt% sulfur coal. Thus, despite its complexity, the potential savings with the AHGP encourage further development and scaleup of this advanced process.

  20. Components development for sulfuric acid processing in the IS process

    International Nuclear Information System (INIS)

    The Japan Atomic Energy Agency (JAEA) has been conducting research and development on a thermochemical iodine–sulfur (IS) process, one of most attractive water-splitting hydrogen production methods, that uses the nuclear heat of a high-temperature gas-cooled reactor (HTGR). An examination is planned to verify the integrity of the components in the sulfuric acid decomposition section. A bayonet-type sulfuric acid decomposer made of SiC ceramics, a key component in the section, was test-fabricated. In parallel, a direct-contact heat exchanger (DCHX) is contemplated for use in the sulfuric acid decomposition section to simplify the process. The application of the DCHX makes it possible to perform heat recovery and separate undecomposed sulfuric acid from the decomposed gaseous mixture in one reactor. Although the concept is very attractive, little is known about the heat and mass transfer behavior in the DCHX. Therefore, a test apparatus was constructed to measure the gas-phase mass transfer coefficients required for the optimal design of the DCHX. These coefficients of water were acquired and compared with an empirical correlation. The experimental data were in good agreement with those obtained from empirical correlation, and thus, the apparatus was confirmed to be reasonable

  1. Uranium recovery process

    International Nuclear Information System (INIS)

    A process of recovering uranium from an aqueous medium containing both it and sulfuric acid which comprises contacting the medium with an anion exchange resin having tertiary amine groups, said resin being the product of (a) the reaction of polyethyleneimine and a dihaloalkane and (b) the subsequent reductive alkylation of the product of (a)

  2. Efficient regulation of elemental sulfur recovery through optimizing working height of upflow anaerobic sludge blanket reactor during denitrifying sulfide removal process.

    Science.gov (United States)

    Huang, Cong; Li, Zhi-Ling; Chen, Fan; Liu, Qian; Zhao, You-Kang; Gao, Ling-Fang; Chen, Chuan; Zhou, Ji-Zhong; Wang, Ai-Jie

    2016-01-01

    In this study, two lab-scale UASB reactors were established to testify S(0) recovery efficiency, and one of which (M-UASB) was improved from the previous T-UASB by shortening reactor height once S(2-) over oxidation was observed. After the height was shortened from 60 to 30cm, S(0) recovery rate was improved from 7.4% to 78.8%, and while, complete removal of acetate, nitrate and S(2-) was simultaneously maintained. Meanwhile, bacterial community distribution was homogenous throughout the reactor, with denitrifying sulfide oxidization bacteria predominant, such as Thauera and Azoarcus spp., indicating the optimized condition for S(0) recovery. The effective control of working height/volume in reactors plays important roles for the efficient regulation of S(0) recovery during DSR process. PMID:26497112

  3. RECOVERY OF CALCIUM CARBONATE AND SULFUR FROM FGD SCRUBBER WASTE

    Science.gov (United States)

    The report gives results of a demonstration of key process steps in the proprietary Kel-S process for recovering calcium carbonate and sulfur from lime/limestone flue gas desulfurization (FGD) scrubber waste. The steps are: reduction of the waste to calcium sulfide (using coal as...

  4. Advanced byproduct recovery: Direct catalytic reduction of sulfur dioxide to elemental sulfur. Quarterly report, April 1--June 30, 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The team of Arthur D. Little, Tufts University and Engelhard Corporation are conducting Phase 1 of a four and a half year, two-phase effort to develop and scale-up an advanced byproduct recovery technology that is a direct, single-stage, catalytic process for converting sulfur dioxide to elemental sulfur. This catalytic process reduces SO{sub 2} over a fluorite-type oxide (such as ceria and zirconia). The catalytic activity can be significantly promoted by active transition metals, such as copper. More than 95% elemental sulfur yield, corresponding to almost complete sulfur dioxide conversion, was obtained over a Cu-Ce-O oxide catalyst as part of an on-going DOE-sponsored, University Coal Research Program. This type of mixed metal oxide catalyst has stable activity, high selectivity for sulfur production, and is resistant to water and carbon dioxide poisoning. Tests with CO and CH{sub 4} reducing gases indicate that the catalyst has the potential for flexibility with regard to the composition of the reducing gas, making it attractive for utility use. The performance of the catalyst is consistently good over a range of SO{sub 2} inlet concentration (0.1 to 10%) indicating its flexibility in treating SO{sub 2} tail gases as well as high concentration streams. The principal objective of the Phase 1 program is to identify and evaluate the performance of a catalyst which is robust and flexible with regard to choice of reducing gas. In order to achieve this goal, the authors have planned a structured program including: Market/process/cost/evaluation; Lab-scale catalyst preparation/optimization studies; Lab-scale, bulk/supported catalyst kinetic studies; Bench-scale catalyst/process studies; and Utility review. Progress is reported from all three organizations.

  5. Recovery and separation of sulfuric acid and iron from dilute acidic sulfate effluent and waste sulfuric acid by solvent extraction and stripping.

    Science.gov (United States)

    Qifeng, Wei; Xiulian, Ren; Jingjing, Guo; Yongxing, Chen

    2016-03-01

    The recovery and simultaneous separation of sulfuric acid and iron from dilute acidic sulfate effluent (DASE) and waste sulfuric acid (WSA) have been an earnest wish for researchers and the entire sulfate process-based titanium pigment industry. To reduce the pollution of the waste acid and make a comprehensive use of the iron and sulfuric acid in it, a new environmentally friendly recovery and separation process for the DASE and the WSA is proposed. This process is based on the reactive extraction of sulfuric acid and Fe(III) from the DASE. Simultaneously, stripping of Fe(III) is carried out in the loaded organic phase with the WSA. Compared to the conventional ways, this innovative method allows the effective extraction of sulfuric acid and iron from the DASE, and the stripping of Fe(III) from the loaded organic phase with the WSA. Trioctylamine (TOA) and tributyl phosphate (TBP) in kerosene (10-50%) were used as organic phases for solvent extraction. Under the optimal conditions, about 98% of Fe(III) and sulfuric acid were removed from the DASE, and about 99.9% of Fe(III) in the organic phase was stripped with the WSA. PMID:26546698

  6. Development of enhanced sulfur rejection processes

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, R.H.; Luttrell, G.H.; Adel, G.T.; Richardson, P.E.

    1996-03-01

    Research at Virginia Tech led to the development of two complementary concepts for improving the removal of inorganic sulfur from many eastern U.S. coals. These concepts are referred to as Electrochemically Enhanced Sulfur Rejection (EESR) and Polymer Enhanced Sulfur Rejection (PESR) processes. The EESR process uses electrochemical techniques to suppress the formation of hydrophobic oxidation products believed to be responsible for the floatability of coal pyrite. The PESR process uses polymeric reagents that react with pyrite and convert floatable middlings, i.e., composite particles composed of pyrite with coal inclusions, into hydrophilic particles. These new pyritic-sulfur rejection processes do not require significant modifications to existing coal preparation facilities, thereby enhancing their adoptability by the coal industry. It is believed that these processes can be used simultaneously to maximize the rejection of both well-liberated pyrite and composite coal-pyrite particles. The project was initiated on October 1, 1992 and all technical work has been completed. This report is based on the research carried out under Tasks 2-7 described in the project proposal. These tasks include Characterization, Electrochemical Studies, In Situ Monitoring of Reagent Adsorption on Pyrite, Bench Scale Testing of the EESR Process, Bench Scale Testing of the PESR Process, and Modeling and Simulation.

  7. Advanced Byproduct Recovery: Direct Catalytic Reduction of Sulfur Dioxide to Elemental Sulfur.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    More than 170 wet scrubber systems applied, to 72,000 MW of U.S., coal-fired, utility boilers are in operation or under construction. In these systems, the sulfur dioxide removed from the boiler flue gas is permanently bound to a sorbent material, such as lime or limestone. The sulfated sorbent must be disposed of as a waste product or, in some cases, sold as a byproduct (e.g. gypsum). Due to the abundance and low cost of naturally occurring gypsum, and the costs associated with producing an industrial quality product, less than 7% of these scrubbers are configured to produce usable gypsum (and only 1% of all units actually sell the byproduct). The disposal of solid waste from each of these scrubbers requires a landfill area of approximately 200 to 400 acres. In the U.S., a total of 19 million tons of disposable FGD byproduct are produced, transported and disposed of in landfills annually. The use of regenerable sorbent technologies has the potential to reduce or eliminate solid waste production, transportation and disposal. In a regenerable sorbent system, the sulfur dioxide in the boiler flue gas is removed by the sorbent in an adsorber. The S0{sub 2}s subsequently released, in higher concentration, in a regenerator. All regenerable systems produce an off-gas stream from the regenerator that must be processed further in order to obtain a salable byproduct, such as elemental sulfur, sulfuric acid or liquid S0{sub 2}.

  8. Sulfuric acid recovery from rare earth sulphate solutions by diffusion dialysis

    Institute of Scientific and Technical Information of China (English)

    TANG Jian-jun; ZHOU Kang-gen; ZHANG Qi-xiu

    2006-01-01

    Sulfuric acid recovery from rare earth sulphate solutions by diffusion dialysis was studied. The mass transfer model of diffusion dialysis was established, the comparison between the experimental results and mathematical results was carried out, and the numerical analysis on the effects of operational parameters was studied. The results indicate that the derived mathematical model shows good quantitative relation between sulphuric acid recovery ratio and operational parameters, and the mathematical results agree with the experimental results well. The numerical analysis results indicate that it is appropriate to keep the ratio of water and feed flow rates, processing capacity per membrane area and recovery ratio of sulphuric acid to be 1, 20 L/(m2·d) and 0.7-0.8,respectively.

  9. Hydrometallurgical recovery of metal values from sulfuric acid leaching liquor of spent lithium-ion batteries.

    Science.gov (United States)

    Chen, Xiangping; Chen, Yongbin; Zhou, Tao; Liu, Depei; Hu, Hang; Fan, Shaoyun

    2015-04-01

    Environmentally hazardous substances contained in spent Li-ion batteries, such as heavy metals and nocuous organics, will pose a threat to the environment and human health. On the other hand, the sustainable recycling of spent lithium-ion batteries may bring about environmental and economic benefits. In this study, a hydrometallurgical process was adopted for the comprehensive recovery of nickel, manganese, cobalt and lithium from sulfuric acid leaching liquor from waste cathode materials of spent lithium-ion batteries. First, nickel ions were selectively precipitated and recovered using dimethylglyoxime reagent. Recycled dimethylglyoxime could be re-used as precipitant for nickel and revealed similar precipitation performance compared with fresh dimethylglyoxime. Then the separation of manganese and cobalt was conducted by solvent extraction method using cobalt loaded D2EHPA. And McCabe-Thiele isotherm was employed for the prediction of the degree of separation and the number of extraction stages needed at specific experimental conditions. Finally, cobalt and lithium were sequentially precipitated and recovered as CoC2O4 ⋅ 2H2O and Li2CO3 using ammonium oxalate solution and saturated sodium carbonate solution, respectively. Recovery efficiencies could be attained as follows: 98.7% for Ni; 97.1% for Mn, 98.2% for Co and 81.0% for Li under optimized experimental conditions. This hydrometallurgical process may promise a candidate for the effective separation and recovery of metal values from the sulfuric acid leaching liquor. PMID:25619126

  10. PROCESS ANALYSIS AND OPTIMIZATION OF AMMONIA BURNING IN A SULFUR RECOVERY UNIT%硫磺回收装置烧氨过程分析及条件优化

    Institute of Scientific and Technical Information of China (English)

    马恒亮; 唐战胜; 耿庆光

    2012-01-01

    对中国石化洛阳分公司硫磺回收装置在烧氨过程中遇到的问题进行分析,结合实际操作情况,提出烧氨条件优化方案.结果表明,适当提高风气比、提高酸性气进炉温度、调节燃烧气氨的负荷和优化仪表控制方案后,一、二级反应器的入口和床层间的温差均增大,系统压力基本维持在0.038MPa左右,急冷水中NH3-N质量浓度控制在300 mg/L左右,取得了较好的综合效益.%After a period of operation and analysis, the process conditions of ammonia burning at the sulfur recovery unit of SINOPEC Luoyang Branch Company were optimized. Results showed that by increasing the air/feed gas volume ratio and the inlet temperature of sour gas to furnace, adjusting the volume fraction of ammonia in sour gas and optimizing instrumentation and control, the temperature difference of reactor inlet and bed layer increased to ensure fully reactions; the system pressure was maintained at 0. 038 MPa and the NH3-N content in quench water was around 300 mg/L. Good economic, environmental and social benefits were obtained.

  11. Gas recovery process

    International Nuclear Information System (INIS)

    In order to decontaminate a gas stream containing radioactive krypton, a preliminary step of removing oxygen and oxides of nitrogen by catalytic reaction with hydrogen is performed. The gas stream is then passed serially through a drier, a carbon dioxide adsorber and a xenon adsorber to remove sequentially water, CO2 and xenon therefrom. The gas exiting the xenon adsorber is passed to a krypton recovery plant wherein krypton is concentrated to a first level in a primary distillation column by contact with a reflux liquid in a packed section of the column. The liquid and vapour collecting at the bottom of the column is passed to a separator in which the liquid is separated from the vapour. The liquid is partially evaporated in a vessel to increase concentration thereof and is brought to a concentration of approximately 90 mole % or greater in a second distillation column thereby enabling efficient storage of a radioactive krypton product. (author)

  12. Sulfur by-product formation in the Stretford process. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Trofe, T.W.; DeBerry, D.W.

    1993-09-01

    Liquid redox sulfur recovery processes remove H2S from sour gas streams and produce elemental sulfur for sale or disposal. The Stretford Process is one of the oldest commercial liquid redox processes and it is based on a vanadium and anthraquinone redox system. Improvements in the operability and reliability of the Stretford process would be beneficial to the process user. The report presents results of research focused on developing an understanding of the process parameters and factors that impact sulfur by-product formation (e.g., sodium thiosulfate and sodium sulfate) in the Stretford process. The information in the report can help current Stretford plant process users better understand the operations of their plants, especially with regards to sulfur by-product formation and control strategies.

  13. Hydrometallurgical recovery of metal values from sulfuric acid leaching liquor of spent lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: • Selective precipitation and solvent extraction were adopted. • Nickel, cobalt and lithium were selectively precipitated. • Co-D2EHPA was employed as high-efficiency extraction reagent for manganese. • High recovery percentages could be achieved for all metal values. - Abstract: Environmentally hazardous substances contained in spent Li-ion batteries, such as heavy metals and nocuous organics, will pose a threat to the environment and human health. On the other hand, the sustainable recycling of spent lithium-ion batteries may bring about environmental and economic benefits. In this study, a hydrometallurgical process was adopted for the comprehensive recovery of nickel, manganese, cobalt and lithium from sulfuric acid leaching liquor from waste cathode materials of spent lithium-ion batteries. First, nickel ions were selectively precipitated and recovered using dimethylglyoxime reagent. Recycled dimethylglyoxime could be re-used as precipitant for nickel and revealed similar precipitation performance compared with fresh dimethylglyoxime. Then the separation of manganese and cobalt was conducted by solvent extraction method using cobalt loaded D2EHPA. And McCabe–Thiele isotherm was employed for the prediction of the degree of separation and the number of extraction stages needed at specific experimental conditions. Finally, cobalt and lithium were sequentially precipitated and recovered as CoC2O4⋅2H2O and Li2CO3 using ammonium oxalate solution and saturated sodium carbonate solution, respectively. Recovery efficiencies could be attained as follows: 98.7% for Ni; 97.1% for Mn, 98.2% for Co and 81.0% for Li under optimized experimental conditions. This hydrometallurgical process may promise a candidate for the effective separation and recovery of metal values from the sulfuric acid leaching liquor

  14. Hydrometallurgical recovery of metal values from sulfuric acid leaching liquor of spent lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiangping; Chen, Yongbin; Zhou, Tao, E-mail: zhoutao@csu.edu.cn; Liu, Depei; Hu, Hang; Fan, Shaoyun

    2015-04-15

    Highlights: • Selective precipitation and solvent extraction were adopted. • Nickel, cobalt and lithium were selectively precipitated. • Co-D2EHPA was employed as high-efficiency extraction reagent for manganese. • High recovery percentages could be achieved for all metal values. - Abstract: Environmentally hazardous substances contained in spent Li-ion batteries, such as heavy metals and nocuous organics, will pose a threat to the environment and human health. On the other hand, the sustainable recycling of spent lithium-ion batteries may bring about environmental and economic benefits. In this study, a hydrometallurgical process was adopted for the comprehensive recovery of nickel, manganese, cobalt and lithium from sulfuric acid leaching liquor from waste cathode materials of spent lithium-ion batteries. First, nickel ions were selectively precipitated and recovered using dimethylglyoxime reagent. Recycled dimethylglyoxime could be re-used as precipitant for nickel and revealed similar precipitation performance compared with fresh dimethylglyoxime. Then the separation of manganese and cobalt was conducted by solvent extraction method using cobalt loaded D2EHPA. And McCabe–Thiele isotherm was employed for the prediction of the degree of separation and the number of extraction stages needed at specific experimental conditions. Finally, cobalt and lithium were sequentially precipitated and recovered as CoC{sub 2}O{sub 4}⋅2H{sub 2}O and Li{sub 2}CO{sub 3} using ammonium oxalate solution and saturated sodium carbonate solution, respectively. Recovery efficiencies could be attained as follows: 98.7% for Ni; 97.1% for Mn, 98.2% for Co and 81.0% for Li under optimized experimental conditions. This hydrometallurgical process may promise a candidate for the effective separation and recovery of metal values from the sulfuric acid leaching liquor.

  15. Nickel recovery from spent Raneynickel catalyst through dilute sulfuric acid leaching and soda ash precipitation.

    Science.gov (United States)

    Lee, Jin Young; Rao, S Venkateswara; Kumar, B Nagaphani; Kang, Dong Jun; Reddy, B Ramachandra

    2010-04-15

    Pharmaceutical industry makes extensive use of Raneynickel catalyst for various organic drug intermediates/end products. Spent catalysts contain environmentally critical and economically valuable metals. In the present study, a simple hydrometallurgical process using dilute sulfuric acid leaching was described for the recovery of nickel from spent Raneynickel catalyst. Recovery of nickel varied with acid concentration and time, whereas temperature had negligible effect. Increase of S/L ratio to 30% (w/v) showed marginal effect on nickel (90%) recovery, whereas Al recovery decreased drastically to approximately 20%. Under the optimum conditions of leaching viz: 12 vol.% H(2)SO(4), 30 degrees C, 20% solid to liquid (S/L) ratio and 120 min reaction time, it was possible to recover 98.6% Ni along with 39.2% Al. Leach liquor [pH 0.7] containing 85.0 g/L Ni and 3.25 g/L Al was adjusted to pH 5.4 with 30 wt.% alkali for quantitative aluminum removal. Nickel loss was about 2% during this Al removal step. Nickel from the purified leach liquor was recovered as nickel carbonate by adding required amount of Na(2)CO(3). The purity of NiCO(3) product was found to be 100% with a Ni content of 48.6%. Na(2)SO(4) was recovered as a by-product with a purity of 99%. Complete process is presented. PMID:20018448

  16. Ultrasound effects on zinc recovery from EAF dust by sulfuric acid leaching

    Science.gov (United States)

    Brunelli, K.; Dabalà, M.

    2015-04-01

    In this work, an ultrasound-assisted leaching process was studied for the recovery of zinc from electric arc furnace (EAF) dust, in which zinc was mainly present in the form of franklinite (60%). Hydrometallurgy is emerging as a preferred process for the recovery of a variety of metals, and the use of ultrasound could offer advantages over the conventional leaching process, especially for the dissolution of franklinite. Franklinite is a refractory phase that is difficult to leach and represents the main obstacle in conventional hydrometallurgy processing. Atmospheric leaching with different sulfuric acid concentrations (0.2-2.0 M) at two temperatures (323 and 353 K) was performed. The tests were conducted using both conventional and ultrasound-assisted leaching. After the leaching tests, the solid residues were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques, whereas the leach liquor was analyzed by inductively coupled plasma spectroscopy (ICP). The use of ultrasound facilitated the dissolution of franklinite at low acid concentrations and resulted in a greater zinc recovery under all of the investigated operating conditions.

  17. Spent oil recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Borza, M.; Leoncini, S.; Modenesi, A.

    1983-09-27

    A process is disclosed for reclaiming spent oil comprises the steps of removing water and light hydrocarbons, thermally treating the stripped oil, extracting it with a supercritical gas to insolubilize impurities and additives, separating the gas-rich fractions from the oil-depleted gas fractions, expanding the insoluble fractions, separating the additives and impurities, separating the various hydrocarbon fractions according to the respective viscosities, compressing and recycling the gas phases and withdrawing the residue and the oil fractions according to the respective viscosities.

  18. Vanadium recovery process

    International Nuclear Information System (INIS)

    A process for recovering vanadium values from carbonaceous type vanadium ores, and vanadium scrap, such as vanadium contaminated spent catalyst, is disclosed which comprises roasting the vanadium containing material in air at a temperature less than about 6000C to produce a material substantially devoid of organic matter, subjecting said roasted material to a further oxidizing roast in an oxygen atmosphere at a temperature of at least about 8000C for a period sufficient to convert substantially all of the vanadium to the soluble form, leaching the calcine with a suitable dilute mineral acid or water at a pH of neutral to about 2 to recover vanadium values, precipitating vanadium values as iron vanadate from the leach solution with a soluble iron compound at a pH from neutral to about 1, and recovering ferrovanadium from the iron vanadate by a reduction vacuum smelting operation. The conversion of vanadium in the ore to the soluble form by the oxidizing roast is accomplished without the addition of an alkaline salt during calcining

  19. Amoco-US Environmental Protection Agency, pollution prevention project, Yorktown, Virginia: Pollution prevention workshop

    International Nuclear Information System (INIS)

    On March 25-27, 1991, a workshop was held in Williamsburg, VA, to review Multi-media (air, water, land) data on environmental releases from Amoco Oil Company's Yorktown Virginia Refinery. Following the data review and a Refinery tour, breakout sessions were held to brainstorm on various topics including (1) process changes to reduce emissions, (2) groundwater protection, (3) criteria for ranking alternatives, (4) permitting issues, (5) general obstacles and incentives, and (6) maintenance and operating practices

  20. Sulfur Isotopic Characteristics of Coal in China and Sulfur Isotopic Fractionation during Coal—burning Process

    Institute of Scientific and Technical Information of China (English)

    洪业汤; 张鸿斌; 等

    1993-01-01

    The determined results of the sulfur contents and isotopic composition of coal samples from major coal mines in 15 provinces and regions of China show that the coal mined in the north of China is characterized by higher 34S and lower sulfur content, but that in the south of China has lower 34S and higher sulfur content.During the coal-burning process in both indrstrial and daily use of coal as fuel the released sulfur dioxide is always enriched in lighter sulfur isotope relative to the corresponding coal;the particles are always enriched in heavier sulfur isotope.The discussion on the environmental geochemical significance of the above-mentioned results also has been made.

  1. Gasoline from natural gas by sulfur processing

    Energy Technology Data Exchange (ETDEWEB)

    Erekson, E.J.; Miao, F.Q. [Institute of Gas Technology, Des Plaines, IL (United States)

    1995-12-31

    The overall objective of this research project is to develop a catalytic process to convert natural gas to liquid transportation fuels. The process, called the HSM (Hydrogen Sulfide-Methane) Process, consists of two steps that each utilize a catalyst and sulfur-containing intermediates: (1) converting natural gas to CS{sub 2} and (2) converting CS{sub 2} to gasoline range liquids. Catalysts have been found that convert methane to carbon disulfide in yields up to 98%. This exceeds the target of 40% yields for the first step. The best rate for CS{sub 2} formation was 132 g CS{sub 2}/kg-cat-h. The best rate for hydrogen production is 220 L H{sub 2} /kg-cat-h. A preliminary economic study shows that in a refinery application hydrogen made by the HSM technology would cost $0.25-R1.00/1000 SCF. Experimental data will be generated to facilitate evaluation of the overall commercial viability of the process.

  2. Development of once-through hybrid sulfur process for nuclear hydrogen production

    International Nuclear Information System (INIS)

    without concentration process depending on the acid concentration they need. It is reasonable to assume that nearly all the recovered sulfur is reportedly consumed after first converted to sulfuric acid, which is the leading sulfur end-use in all forms. Ot-HyS could meet the additionally rising sulfuric acid demand by feeding severely increasing sulfur surplus. Flowsheet for the sulfur combustion and SCHRS (Sulfur Combustion Heat Recovery System) including Rankine cycle, developed by referring to the existing facilities under some assumptions, was simulated using Aspen Plus with an ideal Henry model and STEAMNBS model. Other part of the flowsheet, modified from the SRNL's work, was simulated using Aspen Plus with OLI-MSE model. Acid concentration of sulfuric acid product was set to be 75 wt% and SDE was treated as a black box under the reasonable assumptions including a cell potential of 0.6 V versus current density of 500 mA/cm2, which is a development performance target of the SRNL. As the results, it was demonstrated that net thermal efficiency of Ot-HyS is 47.1 % (based on LHV) and 55.7 % (based on HHV) assuming 33.3 % thermal-to-electric conversion efficiency of nuclear power plant. Hydrogen produced through the energy-efficient Ot-HyS would be used as off-peak electricity storage, to relieve the burden of load-following and help to expand applications of nuclear energy, which is regarded as a 'sustainable development' technology. Further detailed economic feasibility study could help to show the feasibility of Ot-HyS

  3. Spontaneous electrochemical treatment for sulfur recovery by a sulfide oxidation/vanadium(V) reduction galvanic cell.

    Science.gov (United States)

    Kijjanapanich, Pimluck; Kijjanapanich, Pairoje; Annachhatre, Ajit P; Esposito, Giovanni; Lens, Piet N L

    2015-02-01

    Sulfide is the product of the biological sulfate reduction process which gives toxicity and odor problems. Wastewaters or bioreactor effluents containing sulfide can cause severe environmental impacts. Electrochemical treatment can be an alternative approach for sulfide removal and sulfur recovery from such sulfide rich solutions. This study aims to develop a spontaneous electrochemical sulfide oxidation/vanadium(V) reduction cell with a graphite electrode system to recover sulfide as elemental sulfur. The effects of the internal and external resistance on the sulfide removal efficiency and electrical current produced were investigated at different pH. A high surface area of the graphite electrode is required in order to have as less internal resistance as possible. In this study, graphite powder was added (contact area >633 cm(2)) in order to reduce the internal resistance. A sulfide removal efficiency up to 91% and electrical charge of more than 400 C were achieved when using five graphite rods supplemented with graphite powder as the electrode at an external resistance of 30 Ω and a sulfide concentration of 250 mg L(-1). PMID:25463589

  4. Uranium, Cesium, and Mercury Leaching and Recovery from Cemented Radioactive Wastes in Sulfuric Acid and Iodide Media

    Directory of Open Access Journals (Sweden)

    Nicolas Reynier

    2015-11-01

    Full Text Available The Canadian Nuclear Laboratories (CNL is developing a long-term management strategy for its existing inventory of solid radioactive cemented wastes, which contain uranium, mercury, fission products, and a number of minor elements. The composition of the cemented radioactive waste poses significant impediments to the extraction and recovery of uranium using conventional technology. The goal of this research was to develop an innovative method for uranium, mercury and cesium recovery from surrogate radioactive cemented waste (SRCW. Leaching using sulfuric acid and saline media significantly improves the solubilization of the key elements from the SRCW. Increasing the NaCl concentration from 0.5 to 4 M increases the mercury solubilization from 82% to 96%. The sodium chloride forms a soluble mercury complex when mercury is present as HgO or metallic mercury but not with HgS that is found in 60 °C cured SRCW. Several leaching experiments were done using a sulfuric acid solution with KI to leach SRCW cured at 60 °C and/or aged for 30 months. Solubilization yields are above 97% for Cs and 98% for U and Hg. Leaching using sulfuric acid and KI improves the solubilization of Hg by oxidation of Hg0, as well as HgS, and form a mercury tetraiodide complex. Hg and Cs were selectively removed from the leachate prior to uranium recovery. It was found that U recovery from sulfuric leachate in iodide media using the resin Lewatit TP260 is very efficient. Considering these results, a process including effluent recirculation was applied. Improvements of solubilization due to the recycling of chemical reagents were observed during effluent recirculation.

  5. 某硫精矿焙烧-氰化回收金试验研究%Study on the gold recovery from sulfur concentrates by roasting-cyanidation gold leaching process

    Institute of Scientific and Technical Information of China (English)

    邓莉莉

    2015-01-01

    某硫精矿中含铁42.3%、有效硫47.34%、金0.72 g/t,对其进行了焙烧—氰化浸金试验研究。其结果表明:在750℃下焙烧2 h,获得含铁61.42%、金品位1.04 g/t的焙砂;在硝酸铅添加量为300 g/t条件下,对该焙砂进行氰化浸金时,浸渣金品位可降低至0.33 g/t,金浸出率可达68.27%。%Roasting-cyanidation gold leaching process is carried out toward a sulfur concentrate with iron grade of 42. 3%,effective sulfur 47. 34% and gold 0. 72 g/t. The result is that:roasting with the temperature of 750℃ for two hours obtains calcine with 61 . 42 % iron and 1 . 04 g/t gold; The gold grade of cyanide slag can be reduced to 0. 33 g/t and gold leaching rate can reach 68. 27 %,when the cyanide leaching of gold from the calcine with 300 g/t lead nitrate added.

  6. Sulfur Flow Analysis for New Generation Steel Manufacturing Process

    Institute of Scientific and Technical Information of China (English)

    HU Chang-qing; ZHANG Chun-xia; HAN Xiao-wei; YIN Rui-yu

    2008-01-01

    Sulfur flow for new generation steel manufacturing process is analyzed by the method of material flow analysis,and measures for SO2 emission reduction are put forward as assessment and target intervention of the results.The results of sulfur flow analysis indicate that 90% of sulfur comes from fuels.Sulfur finally discharges from the steel manufacturing route in various steps,and the main point is BF and BOF slag desulfurization.In sintering process,the sulfur is removed by gasification,and sintering process is the main source of SO2 emission.The sulfur content of coke oven gas (COG) is an important factor affecting SO2 emission.Therefore,SO2 emission reduction should be started from the optimization and integration of steel manufacturing route,sulfur burden should be reduced through energy saving and consumption reduction,and the sulfur content of fuel should be controlled.At the same time,BF and BOF slag desulfurization should be optimized further and coke oven gas and sintering exhausted gas desulfurization should be adopted for SO2 emission reduction and reuse of resource,to achieve harmonic coordination of economic,social,and environmental effects for sustainable development.

  7. Once-through hybrid sulfur process for nuclear hydrogen production

    International Nuclear Information System (INIS)

    Increasing concern about the global climate change spurs the development of low- or zero-carbon energy system. Nuclear hydrogen production by water electrolysis would be the one of the short-term solutions, but low efficiency and high production cost (high energy consumption) is the technical hurdle to be removed. In this paper the once-through sulfur process composed of the desulfurization and the water electrolysis systems is proposed. Electrode potential for the conventional water electrolysis (∼2.0 V) can be reduced significantly by the anode depolarization using sulfur dioxide: down to 0.6 V depending on the current density This depolarized electrolysis is the electrolysis step of the hybrid sulfur process originally proposed by the Westinghouse. However; recycling of sulfur dioxide requires a high temperature heat source and thus put another technical hurdle on the way to nuclear hydrogen production: the development of high temperature nuclear reactors and corresponding sulfuric acid decomposition system. By the once-through use of sulfur dioxide rather than the closed recycle, the hurdle can be removed. For the sulfur feed, the desulfurization system is integrated into the water electrolysis system. Fossil fuels include a few percent of sulfur by weight. During the refinement or energy conversion, most of the sulfur should be separated The separated sulfur can be fed to the water electrolysis system and the final product would be hydrogen and sulfuric acid, which is number one chemical in the world by volume. Lowered electrode potential and additional byproduct, the sulfuric acid, can provide economically affordable hydrogen. In this study, the once-through hybrid sulfur process for hydrogen production was proposed and the process was optimized considering energy consumption in electrolysis and sulfuric acid concentration. Economic feasibility of the proposed process was also discussed. Based on currently available experimental data for the electrode

  8. A microencapsulation process of liquid mercury by sulfur polymer

    OpenAIRE

    López-Delgado, Aurora; Guerrero, A; López Gómez, Félix Antonio; Pérez, Carlos; Alguacil, Francisco José

    2012-01-01

    Under the European LIFE Program a microencapsulation process was developed for liquid mercury using Sulfur Polymer Stabilization/Solidification (SPSS) technology, obtaining a stable concrete-like sulfur matrix that allows the immobilization of mercury for long-term storage. The process description and characterization of the materials obtained were detailed in Part I. The present document, Part II, reports the results of different tests carried out to determine the durability of H...

  9. Discussion on Stable Operation Factors in Claus Sulfur Recovery%克劳斯硫回收稳定运行因素探讨

    Institute of Scientific and Technical Information of China (English)

    刘婷婷

    2016-01-01

    With the rapid growth of the national economy, our coal chemical industry has been rapid developed. Meanwhile, in order to make emissions meet the national environmental protection requirements, sulfur recovery process also continues to develop and progress. At present, the main technology is the claus process sulfur recovery. This method is usually used to treat the acid gas containing 15% ~17% hydrogen sulfide. By analyzing Claus sulfur recovery works and process, process control was discussed to improve the sulfur recovery rate and reduce SO2 emissions.%随着我国国民经济的快速增长,我国的煤化工领域也得到了高速发展。同时为了使尾气排放达到国家环保要求,硫回收工艺也在不断的发展进步。目前国内硫回收的主要技术是克劳斯法,此法通常处理含硫化氢为15%~100%的酸性气。本文通过克劳斯硫回收的工作原理、工艺流程,探讨了如何通过工艺控制,进而达到提高硫磺回收率、降低SO2排放的目的。

  10. Advanced Byproduct Recovery: Direct Catalytic Reduction of Sulfur Dioxide to Elemental Sulfur. Sixth quarterly technical progress report, January - March 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    More than 170 wet scrubber systems applied, to 72,000 MW of U.S., coal-fired, utility boilers are in operation or under construction. In these systems, the sulfur dioxide removed from the boiler flue gas is permanently bound to a sorbent material, such as lime or limestone. The sulfated sorbent must be disposed of as a waste product or, in some cases, sold as a byproduct (e.g. gypsum). Due to the abundance and low cost of naturally occurring gypsum, and the costs associated with producing an industrial quality product, less than 7% of these scrubbers are configured to produce usable gypsum (and only 1% of all units actually sell the byproduct). The disposal of solid waste from each of these scrubbers requires a landfill area of approximately 200 to 400 acres. In the U.S., a total of 19 million tons of disposable FGD byproduct are produced, transported and disposed of in landfills annually. The use of regenerable sorbent technologies has the potential to reduce or eliminate solid waste production, transportation and disposal. In a regenerable sorbent system, the sulfur dioxide in the boiler flue gas is removed by the sorbent in an adsorber. The S0{sub 2}s subsequently released, in higher concentration, in a regenerator. All regenerable systems produce an off-gas stream from the regenerator that must be processed further in order to obtain a salable byproduct, such as elemental sulfur, sulfuric acid or liquid S0{sub 2}.

  11. Low-quality natural gas sulfur removal/recovery

    Energy Technology Data Exchange (ETDEWEB)

    K. Amo; R.W. Baker; V.D. Helm; T. Hofmann; K.A. Lokhandwala; I. Pinnau; M.B. Ringer; T.T. Su; L. Toy; J.G. Wijmans

    1998-01-29

    A significant fraction of U.S. natural gas reserves are subquality due to the presence of acid gases and nitrogen; 13% of existing reserves (19 trillion cubic feed) may be contaminated with hydrogen sulfide. For natural gas to be useful as fuel and feedstock, this hydrogen sulfide has to be removed to the pipeline specification of 4 ppm. The technology used to achieve these specifications has been amine, or similar chemical or physical solvent, absorption. Although mature and widely used in the gas industry, absorption processes are capital and energy-intensive and require constant supervision for proper operation. This makes these processes unsuitable for treating gas at low throughput, in remote locations, or with a high concentration of acid gases. The U.S. Department of Energy, recognizes that exploitation of smaller, more sub-quality resources will be necessary to meet demand as the large gas fields in the U.S. are depleted. In response to this need, Membrane Technology and Research, Inc. (MTR) has developed membranes and a membrane process for removing hydrogen sulfide from natural gas. During this project, high-performance polymeric thin-film composite membranes were brought from the research stage to field testing. The membranes have hydrogen sulfide/methane selectivities in the range 35 to 60, depending on the feed conditions, and have been scaled up to commercial-scale production. A large number of spiral-wound modules were manufactured, tested and optimized during this project, which culminated in a field test at a Shell facility in East Texas. The short field test showed that membrane module performance on an actual natural gas stream was close to that observed in the laboratory tests with cleaner streams. An extensive technical and economic analysis was performed to determine the best applications for the membrane process. Two areas were identified: the low-flow-rate, high-hydrogen-sulfide-content region and the high-flow-rate, high

  12. Amoco-US Environmental Protection Agency, pollution prevention project, Yorktown, Virginia: Surface water data

    International Nuclear Information System (INIS)

    The report summarizes the surface water sampling program at the Amoco Refinery at Yorktown, Virginia. This was undertaken as a part of the joint project between Amoco Corporation and the United States Environmental Protection Agency to review pollution prevention alternatives at a petroleum refinery. The surface water data provides a snapshot of surface water pollutant generation and discharge from the refinery. Different process units contribute to the total wastewater flow of 460 GPM in the refinery. Water in the ditch system, which is non-process water, is free of organic contamination. Oil and grease, phenols, ammonia and sulfides are the significant components measured in the process wastewater. The concentrations of organics in most water streams leaving the individual process units are relatively low, in the 1-5 parts per million (ppm) range. A few individual streams such as the crude desalter brine and tank water draws have high pollutant loadings. Concentrations of metals in the refinery wastewater are very low. The wastewater treatment plant is very effective in reducing the pollutant loading in the water with overall removal efficiencies greater than 99% for most organics and inorganics

  13. Low-quality natural gas sulfur removal/recovery: Task 2. Topical report, September 30, 1992--August 29, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Cook, W.J.; Neyman, M.; Brown, W. [Acrion Technologies, Inc., Cleveland, OH (United States); Klint, B.W.; Kuehn, L.; O`Connell, J.; Paskall, H.; Dale, P. [Bovar, Inc., Calgary, Alberta (Canada)

    1993-08-01

    The primary purpose of this Task 2 Report is to present conceptual designs developed to treat a large portion of proven domestic natural gas reserves which are low quality. The conceptual designs separate hydrogen sulfide and large amounts of carbon dioxide (>20%) from methane, convert hydrogen sulfide to elemental sulfur, produce a substantial portion of the carbon dioxide as EOR or food grade CO{sub 2}, and vent residual CO{sub 2} virtually free of contaminating sulfur containing compounds. A secondary purpose of this Task 2 Report is to review existing gas treatment technology and identify existing commercial technologies currently used to treat large volumes of low quality natural gas with high acid content. Section II of this report defines low quality gas and describes the motivation for seeking technology to develop low quality gas reserves. The target low quality gas to be treated with the proposed technology is identified, and barriers to the production of this gas are reviewed. Section III provides a description of the Controlled Freeze Zone (CFG)-CNG technologies, their features, and perceived advantages. The three conceptual process designs prepared under Task 2 are presented in Section IV along with the design basis and process economics. Section V presents an overview of existing gas treatment technologies, organized into acid gas removal technology and sulfur recovery technology.

  14. Amoco-US Environmental Protection Agency, pollution prevention project, Yorktown, Virginia: Project peer review. Report of the Peer Review Committee of the Amoco/EPA Pollution Prevention Project at the Yorktown, Virginia refinery

    International Nuclear Information System (INIS)

    The Amoco/EPA Pollution Prevention Project involved a number of representatives from federal and Virginia regulatory agencies, and Amoco's refining business. Participants believed that the Project could benefit from a broader perspective than these organizations along might provide. The Project Work Group selected an independent Peer Review Process which was conducted by Resource for the Future (RFF), a Washington DC think tank. A group of technical, policy and environmental experts from diverse backgrounds served as Peer Review members. The Peer Review Committee met on three occasions to discuss (1) the Project Work Plan (2) sampling data and interpretation and (3) project conclusions and recommendations. The focus of the meeting was on the general scope and content of the project

  15. Birds oiled during the Amoco Cadiz incident: an interim report

    Energy Technology Data Exchange (ETDEWEB)

    Jones, P.H.; Monnat, J.Y.; Cadbury, C.J.; Stowe, T.J.

    1978-11-01

    More than 4500 oiled birds were collected from beaches in Northwest France and the Channel Islands following the oil spillage from the super tanker Amoco Cadiz in March 1978. Some 33 bird species were recorded oiled. A notable feature of the incident was the high proportion of puffins among the birds known to have been oiled. In normal years, puffins are considered to be relatively uncommon off Brittany in spring, and so the high proportion of this species among the casualties was unexpected. A relatively large number of shags and divers were also oiled. (1 map, 8 references, 2 tables)

  16. ADVANCED SULFUR CONTROL CONCEPTS

    Energy Technology Data Exchange (ETDEWEB)

    Apostolos A. Nikolopoulos; Santosh K. Gangwal; William J. McMichael; Jeffrey W. Portzer

    2003-01-01

    Conventional sulfur removal in integrated gasification combined cycle (IGCC) power plants involves numerous steps: COS (carbonyl sulfide) hydrolysis, amine scrubbing/regeneration, Claus process, and tail-gas treatment. Advanced sulfur removal in IGCC systems involves typically the use of zinc oxide-based sorbents. The sulfides sorbent is regenerated using dilute air to produce a dilute SO{sub 2} (sulfur dioxide) tail gas. Under previous contracts the highly effective first generation Direct Sulfur Recovery Process (DSRP) for catalytic reduction of this SO{sub 2} tail gas to elemental sulfur was developed. This process is currently undergoing field-testing. In this project, advanced concepts were evaluated to reduce the number of unit operations in sulfur removal and recovery. Substantial effort was directed towards developing sorbents that could be directly regenerated to elemental sulfur in an Advanced Hot Gas Process (AHGP). Development of this process has been described in detail in Appendices A-F. RTI began the development of the Single-step Sulfur Recovery Process (SSRP) to eliminate the use of sorbents and multiple reactors in sulfur removal and recovery. This process showed promising preliminary results and thus further process development of AHGP was abandoned in favor of SSRP. The SSRP is a direct Claus process that consists of injecting SO{sub 2} directly into the quenched coal gas from a coal gasifier, and reacting the H{sub 2}S-SO{sub 2} mixture over a selective catalyst to both remove and recover sulfur in a single step. The process is conducted at gasifier pressure and 125 to 160 C. The proposed commercial embodiment of the SSRP involves a liquid phase of molten sulfur with dispersed catalyst in a slurry bubble-column reactor (SBCR).

  17. Trace recovery of uranium and rare earth contained in phosphates by liquid-liquid extraction in sulfuric attack liquor

    International Nuclear Information System (INIS)

    Uranium and rare earths can be recovered in sedimentary phosphates during the wet processing of the ore by sulfuric acid giving raw phosphoric acid at 30 per cent of P2O5. Practically all the uranium contained and only part of rare earths are put into solution in this treatment. Separation of these elements in the phosphoric solution is obtained by liquid-liquid extraction with alkylphosphoric acids and especially with their mono and di esters. Partition isotherms are determined and counter-current tests are effected. Uranium and rare earths reextraction from these solvents can be simultaneous or separate with aqueous solutions alkaline or containing HF or by antisynergism. Pros and cons of each reextraction process are discussed. In conclusion HDEHP or OPPA are recommended because of availability, stability and hydrodynamic, OPPA less selective with rare earths allows the recovery with uranium of ceric earths, yttrium and yttric earths

  18. Uranium recovery from wet process phosphoric acid

    International Nuclear Information System (INIS)

    In the field of metallurgy, specifically processes for recovering uranium from wet process phosphoric acid solution derived from the acidulation of uraniferous phosphate ores, problems of imbalance of ion exchange agents, contamination of recycled phosphoric acid with process organics and oxidizing agents, and loss and contamination of uranium product, are solved by removing organics from the raffinate after ion exchange conversion of uranium to uranous form and recovery thereof by ion exchange, and returning organics to the circuit to balance mono and disubstituted ester ion exchange agents; then oxidatively stripping uranium from the agent using hydrogen peroxide; then after ion exchange recovery of uranyl and scrubbing, stripping with sodium carbonate and acidifying the strip solution and using some of it for the scrubbing; regenerating the sodium loaded agent and recycling it to the uranous recovery step. Economic recovery of uranium as a by-product of phosphate fertilizer production is effected. (author)

  19. Process for simultaneously removing sulfur oxides and particulates

    International Nuclear Information System (INIS)

    A gas purification process is described comprising the steps of: withdrawing a particulate-laden gaseous stream comprising particulates and sulfur oxides from a combustor of a processing unit selected from the group consisting of a catalytic cracking unit, a synthetic fuels plant, a coal liquefaction plant, a gasification plant, a power plant, a paper mill, a steel mill, and a waste treatment facility; removing large gross particulates from the particulate-laden gaseous stream in at least one cyclone by passing the particulate-laden gaseous stream through at least one cyclone; feeding the particulate-laden gaseous stream to a vessel after the particulate-laden gaseous stream has been passed through at least one cyclone, the vessel having a bed of sulfur oxide capturing and particulate-removing material comprising at least one member selected from the group consisting of adsorbers and adsorbers with at least one promoter thereon, the adsorbers substantially comprising an oxide of at least one metal selected from the group consisting of aluminum, bismuth, manganese, yttrium, antimony, tin, a rare earth metal, a Group Ia metal, and Group 2a metal, and the promoter selected from the group consisting essentially of a rare earth metal, a Group 8 metal, chromium, vanadium, rhenium, and combinations thereof; substantially decreasing the concentration of both particulates and sulfur oxides in the particulate-laden gaseous stream in the vessel; and the decreasing comprising simultaneously removing a substantial portion of the particulates and a substantial portion of the sulfur oxides from the particulate-laden gaseous stream by passing the particulate-laden gaseous stream through a portion of the bed of sulfur oxide-capturing and particulate-removing material in the vessel

  20. Recovery of vanadium (V) from spent catalysts used in sulfuric acid production units by acid or alkaline leaching

    International Nuclear Information System (INIS)

    The present paper, studies the recovery of vanadium from the spent catalyst by using acidic or alkaline leaching technique. The optimal conditions of spent catalyst leaching have been studied. It has been shown that 20%(w/w) of sulfuric acid is the most suitable for leaching process at 70 Centigrade. The precipitation of vanadium using some alkaline media (Na2CO3, (NH4)CO3 and NH4OH) has been also studied, it has been shown that ammonium hydroxide was the best at 60 degree, and iron was co-precipitated with vanadium which pollute the obtained red cake. So it is necessary to use liquid-liquid extraction technique for the separation between vanadium and iron and to have iron free red cake. (author)

  1. Benzene vapor recovery and processing

    International Nuclear Information System (INIS)

    The National Emissions Standards for Hazardous Air Pollutants, or NESHAPs, have provided a powerful motivation for interest in, and attention to, benzene vapor emissions in recent times. Benzene and its related aromatics are volatile organic compounds (VOCs), which marks them for surveillance as potential contributors to air pollution. In addition, benzene is a suspected carcinogen, which applies a special urgency to its control. The regulations governing the control of benzene emissions were issued as Title 40, Code of Federal Regulations, Part 61, subpart Y (Storage Vessels); subpart BB (Transfer Operations); and subpart FF (Waste Operations). These regulations specify very particular emission reduction guidelines for various generating sources. The problem in the hydrocarbon processing industry is to identify significant sources of benzene vapors in plants, and then to collect and process these vapors in an environmentally acceptable manner. This paper discusses various methods for collecting benzene fumes in these facilities

  2. Hydrothermal alkali metal recovery process

    Science.gov (United States)

    Wolfs, Denise Y.; Clavenna, Le Roy R.; Eakman, James M.; Kalina, Theodore

    1980-01-01

    In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered from the particles by treating them with a calcium or magnesium-containing compound in the presence of water at a temperature between about 250.degree. F. and about 700.degree. F. and in the presence of an added base to establish a pH during the treatment step that is higher than would otherwise be possible without the addition of the base. During the treating process the relatively high pH facilitates the conversion of water-insoluble alkali metal compounds in the alkali metal residues into water-soluble alkali metal constituents. The resultant aqueous solution containing water-soluble alkali metal constituents is then separated from the residue solids, which consist of the treated particles and any insoluble materials formed during the treatment step, and recycled to the gasification process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst. Preferably, the base that is added during the treatment step is an alkali metal hydroxide obtained by water washing the residue solids produced during the treatment step.

  3. Effect of Additive on Sulfur-fixation Process of Sulfur-fixation Agent

    Institute of Scientific and Technical Information of China (English)

    XIE Jun-lin; QIU Jian-rong; ZHAO Gai-ju; LOU Jin-ping; HAN Chun-hua

    2003-01-01

    The crystallization behavior of desulfurization product is directly related to its high-temperatureresistant ability. Effects of the additive on the sulfur-fixation efficiency of the Ba-sulfur-fixation agent and also on the crystallization behavior of the sulfur-fixation product were studied when CaCO3 and BaCO3 were used as the desulfurization agent and MgO and SrCO3 used as the assistant sulfur-fixation agent. The result shows that increase of sulfur-fixation capability for the additive is not owe to their directly react to form sulfate or interact with CaCO3 and BaCO3 to form composite mineral heat-resistant in high temperature, but owe to their activation to sulfur-fixation reaction of the sulfur-fixation agent.

  4. Methods of regulation of sulfur contents at intermediate stages and in products of oil stock. Processing

    OpenAIRE

    Safin Rashit Rafailovich

    2010-01-01

    Mathematical models of distribution of charge flows at oil-processing plants, allowing to optimize sulfur contents at intermediate stages and end pro-ducts, are offered in the paper. The possibility of sulfur contents redistribution in various products by modifying technological parameters of oil products pro-cessing and by changing the directions and (or) the volume of the flows, is shown. This allows to cut down the cost of sulfur refinement and reduce the pollution made by sulfur-containin...

  5. Adsorption Process of Sulfur Removal from Diesel Oil Using Sorbent Materials

    OpenAIRE

    Isam A. H. Al Zubaidy; Fatma Bin Tarsh; Noora Naif Darwish; Balsam Sweidan Sana Abdul Majeed; Aysha Al Sharafi; Lamis Abu Chacra

    2013-01-01

    The removal of organo-sulfur compounds (ORS) from diesel fuel is an important aspect of all countries to reduce air pollution by reducing the emission of toxic gases such as sulfur oxides and other polluted materials. One of the easily and fast method to remove sulfur from diesel oil is the adsorption desulfurization process. Adsorption-desulfurization process of diesel fuel was proposed and examined. Local diesel fuel of 410 ppm sulfur content was treated with commercial activated carbon and...

  6. Recovery of transuranics from process residues

    International Nuclear Information System (INIS)

    Process residues are generated at both the Rocky Flats Plant (RFP) and the Savannah River Plant (SRP) during aqueous chemical and pyrochemical operations. Frequently, process operations will result in either impure products or produce residues sufficiently contaminated with transuranics to be nondiscardable as waste. Purification and recovery flowsheets for process residues have been developed to generate solutions compatible with subsequent Purex operations and either solid or liquid waste suitable for disposal. The ''scrub alloy'' and the ''anode heel alloy'' are examples of materials generated at RFP which have been processed at SRP using the developed recovery flowsheets. Examples of process residues being generated at SRP for which flowsheets are under development include LECO crucibles and alpha-contaminated hydraulic oil

  7. Ecological catastrophe and economical damages. The problems of assessment from Amoco-Cadiz

    International Nuclear Information System (INIS)

    This book strikes the balance of the accident of the tanker ship Amoco-Cadiz (environmental effects and economic impact) and sets the problem of damages assessment, liabilities, victims compensation. 99 refs., 41 figs., 43 tabs

  8. ADVANCED BYPRODUCT RECOVERY: DIRECT CATALYTIC REDUCTION OF SO2 TO ELEMENTAL SULFUR

    Energy Technology Data Exchange (ETDEWEB)

    Robert S. Weber

    1999-05-01

    Arthur D. Little, Inc., together with its commercialization partner, Engelhard Corporation, and its university partner Tufts, investigated a single-step process for direct, catalytic reduction of sulfur dioxide from regenerable flue gas desulfurization processes to the more valuable elemental sulfur by-product. This development built on recently demonstrated SO{sub 2}-reduction catalyst performance at Tufts University on a DOE-sponsored program and is, in principle, applicable to processing of regenerator off-gases from all regenerable SO{sub 2}-control processes. In this program, laboratory-scale catalyst optimization work at Tufts was combined with supported catalyst formulation work at Engelhard, bench-scale supported catalyst testing at Arthur D. Little and market assessments, also by Arthur D. Little. Objectives included identification and performance evaluation of a catalyst which is robust and flexible with regard to choice of reducing gas. The catalyst formulation was improved significantly over the course of this work owing to the identification of a number of underlying phenomena that tended to reduce catalyst selectivity. The most promising catalysts discovered in the bench-scale tests at Tufts were transformed into monolith-supported catalysts at Engelhard. These catalyst samples were tested at larger scale at Arthur D. Little, where the laboratory-scale results were confirmed, namely that the catalysts do effectively reduce sulfur dioxide to elemental sulfur when operated under appropriate levels of conversion and in conditions that do not contain too much water or hydrogen. Ways to overcome those limitations were suggested by the laboratory results. Nonetheless, at the end of Phase I, the catalysts did not exhibit the very stringent levels of activity or selectivity that would have permitted ready scale-up to pilot or commercial operation. Therefore, we chose not to pursue Phase II of this work which would have included further bench-scale testing

  9. Determination of Optimum Process Conditions for Sulfuric Acid Dissolution of Zarigan Thorium-Uranium Ore Using Taguchi Method

    International Nuclear Information System (INIS)

    This paper deals with the study of digestion and leaching process effectiveness in thorium minerals processing, and determining the optimum process conditions for acidic leaching of thorium- uranium ores in Zarigan region to dissolve thorium. To do this, some samples from Zarigan region were studied mineralogically in laboratory. The sample containing minerals such as Anorthite, Quartz, Sanidine, Vermiculite, Albite, Gypsum, Muscovite, Anatase and Magnetite were ground in specified dimensions and then mixed with concentrated sulfuric acid. Then the mixture was heated to a high temperature. After diluting the mixture with water, it was dissolved by means of agitation leaching. The effects of different parameters such as particle size, temperature and time of digestion, concentration of sulfuric acid, and acid to ore ratio, with the aim of determining their optimum value, were studied which resulted in the following optimum values for the above-mentioned parameters: particle size of 250 μm, temperature of 180degreeC, time of 5h, concentration of sulfuric acid of 10.8 mol/lit, and acid to ore ratio of 3. Under these conditions, maximum recovery of thorium was 92%. Nitric acid (oxidant) concentration effect on the recovery of thorium in the optimum conditions was studied, and for the 2M of nitric acid concentration, thorium recovery of 97% was obtained.

  10. Assessing the additional impact of Process Recovery Communications on Customer Outcomes: A Comprehensive Service Recovery Approach

    OpenAIRE

    Y. VAN VAERENBERGH; B. LARIVIÈRE; I. VERMEIR

    2009-01-01

    Purpose – Services recoveries following service failures not only imply customer recovery opportunities in which customer-company relationships can be restored, they can also result in process improvements (i.e. process recoveries in literature). This paper seeks to identify the additional impact of process recoveries on four customer outcome variables (satisfaction with service recovery, overall satisfaction, repurchase intent and word-of-mouth) by communicating these improvements back to th...

  11. Improved Recovery Boiler Performance Through Control of Combustion, Sulfur, and Alkali Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Larry L.

    2008-06-09

    This project involved the following objectives: 1. Determine black liquor drying and devolatilization elemental and total mass release rates and yields. 2. Develop a public domain physical/chemical kinetic model of black liquor drop combustion, including new information on drying and devolatilization. 3. Determine mechanisms and rates of sulfur scavenging in recover boilers. 4. Develop non-ideal, public-domain thermochemistry models for alkali salts appropriate for recovery boilers 5. Develop data and a one-dimensional model of a char bed in a recovery boiler. 6. Implement all of the above in comprehensive combustion code and validate effects on boiler performance. 7. Perform gasification modeling in support of INEL and commercial customers. The major accomplishments of this project corresponding to these objectives are as follows: 1. Original data for black liquor and biomass data demonstrate dependencies of particle reactions on particle size, liquor type, gas temperature, and gas composition. A comprehensive particle submodel and corresponding data developed during this project predicts particle drying (including both free and chemisorbed moisture), devolatilization, heterogeneous char oxidation, char-smelt reactions, and smelt oxidation. Data and model predictions agree, without adjustment of parameters, within their respective errors. The work performed under these tasks substantially exceeded the original objectives. 2. A separate model for sulfur scavenging and fume formation in a recovery boiler demonstrated strong dependence on both in-boiler mixing and chemistry. In particular, accurate fume particle size predictions, as determined from both laboratory and field measurements, depend on gas mixing effects in the boilers that lead to substantial particle agglomeration. Sulfur scavenging was quantitatively predicted while particle size required one empirical mixing factor to match data. 3. Condensed-phase thermochemistry algorithms were developed for salt

  12. A Dynamic Simulation of the Sulfuric Acid Decomposition Process in a Sulfur-Iodine Nuclear Hydrogen Production Plant

    International Nuclear Information System (INIS)

    In order to evaluate the start-up behavior and to identify, through abnormal operation occurrences, the transient behaviors of the Sulfur Iodine(SI) process, which is a nuclear hydrogen process that is coupled to a Very High Temperature Gas Cooled Reactor (VHTR) through an Intermediate Heat Exchanger (IHX), a dynamic simulation of the process is necessary. Perturbation of the flow rate or temperature in the inlet streams may result in various transient states. An understanding of the dynamic behavior due to these factors is able to support the conceptual design of the secondary helium loop system associated with a hydrogen production plant. Based on the mass and energy balance sheets of an electrodialysis-embedded SI process equivalent to a 200 MWth VHTR and a considerable thermal pathway between the SI process and the VHTR system, a dynamic simulation of the SI process was carried out for a sulfuric acid decomposition process (Second Section) that is composed of a sulfuric acid vaporizer, a sulfuric acid decomposer, and a sulfur trioxide decomposer. The dynamic behaviors of these integrated reactors according to several anticipated scenarios are evaluated and the dominant and mild factors are observed. As for the results of the simulation, all the reactors in the sulfuric acid decomposition process approach a steady state at the same time. Temperature control of the inlet helium is strictly required rather than the flow rate control of the inlet helium to keep the steady state condition in the Second Section. On the other hand, it was revealed that the changes of the inlet helium operation conditions make a great impact on the performances of SO3 and H2SO4 decomposers, but no effect on the performance of the H2SO4 vaporizer

  13. SULFURIC ACID REMOVAL PROCESS EVALUATION: SHORT-TERM RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Gary M. Blythe; Richard McMillan

    2002-02-04

    The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. Sulfuric acid controls are becoming of increasing interest to utilities with coal-fired units for a number of reasons. Sulfuric acid is a Toxic Release Inventory species, a precursor to acid aerosol/condensable emissions, and can cause a variety of plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of SCR for NO{sub x} control on some coal-fired plants, as SCR catalysts are known to further oxidize a portion of the flue gas SO{sub 2} to SO{sub 3}. The project is testing the effectiveness of furnace injection of four different calcium- and/or magnesium-based alkaline sorbents on full-scale utility boilers. These reagents have been tested during four one- to two-week tests conducted on two First Energy Bruce Mansfield Plant units. One of the sorbents tested was a magnesium hydroxide slurry produced from a wet flue gas desulfurization system waste stream, from a system that employs a Thiosorbic{reg_sign} Lime scrubbing process. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercial magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners, while the other three reagents were injected as slurries through air-atomizing nozzles into the front wall of upper furnace, either across from the nose of the furnace or across from the pendant superheater tubes. After completing the four one- to two-week tests, the most promising sorbents were selected for longer-term (approximately 25-day) full-scale tests. The longer-term tests are being conducted to confirm the effectiveness of the sorbents tested over extended operation and to determine balance-of-plant impacts. This reports presents

  14. SULFURIC ACID REMOVAL PROCESS EVALUATION: SHORT-TERM RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Gary M. Blythe; Richard McMillan

    2002-03-04

    The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. Sulfuric acid controls are becoming of increasing interest to utilities with coal-fired units for a number of reasons. Sulfuric acid is a Toxic Release Inventory species, a precursor to acid aerosol/condensable emissions, and can cause a variety of plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of SCR for NOX control on some coal-fired plants, as SCR catalysts are known to further oxidize a portion of the flue gas SO{sub 2} to SO{sub 3}. The project is testing the effectiveness of furnace injection of four different calcium- and/or magnesium-based alkaline sorbents on full-scale utility boilers. These reagents have been tested during four one- to two-week tests conducted on two FirstEnergy Bruce Mansfield Plant units. One of the sorbents tested was a magnesium hydroxide slurry produced from a wet flue gas desulfurization system waste stream, from a system that employs a Thiosorbic{reg_sign} Lime scrubbing process. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercial magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners, while the other three reagents were injected as slurries through air-atomizing nozzles into the front wall of upper furnace, either across from the nose of the furnace or across from the pendant superheater tubes. After completing the four one- to two-week tests, the most promising sorbents were selected for longer-term (approximately 25-day) full-scale tests. The longer-term tests are being conducted to confirm the effectiveness of the sorbents tested over extended operation and to determine balance-of-plant impacts. This reports presents the

  15. SULFURIC ACID REMOVAL PROCESS EVALUATION: SHORT-TERM RESULTS; TOPICAL

    International Nuclear Information System (INIS)

    The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. Sulfuric acid controls are becoming of increasing interest to utilities with coal-fired units for a number of reasons. Sulfuric acid is a Toxic Release Inventory species, a precursor to acid aerosol/condensable emissions, and can cause a variety of plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of SCR for NO(sub x) control on some coal-fired plants, as SCR catalysts are known to further oxidize a portion of the flue gas SO(sub 2) to SO(sub 3). The project is testing the effectiveness of furnace injection of four different calcium- and/or magnesium-based alkaline sorbents on full-scale utility boilers. These reagents have been tested during four one- to two-week tests conducted on two First Energy Bruce Mansfield Plant units. One of the sorbents tested was a magnesium hydroxide slurry produced from a wet flue gas desulfurization system waste stream, from a system that employs a Thiosorbic(regsign) Lime scrubbing process. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercial magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners, while the other three reagents were injected as slurries through air-atomizing nozzles into the front wall of upper furnace, either across from the nose of the furnace or across from the pendant superheater tubes. After completing the four one- to two-week tests, the most promising sorbents were selected for longer-term (approximately 25-day) full-scale tests. The longer-term tests are being conducted to confirm the effectiveness of the sorbents tested over extended operation and to determine balance-of-plant impacts. This reports presents

  16. SULFURIC ACID REMOVAL PROCESS EVALUATION: SHORT-TERM RESULTS; TOPICAL

    International Nuclear Information System (INIS)

    The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. Sulfuric acid controls are becoming of increasing interest to utilities with coal-fired units for a number of reasons. Sulfuric acid is a Toxic Release Inventory species, a precursor to acid aerosol/condensable emissions, and can cause a variety of plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of SCR for NOX control on some coal-fired plants, as SCR catalysts are known to further oxidize a portion of the flue gas SO(sub 2) to SO(sub 3). The project is testing the effectiveness of furnace injection of four different calcium- and/or magnesium-based alkaline sorbents on full-scale utility boilers. These reagents have been tested during four one- to two-week tests conducted on two FirstEnergy Bruce Mansfield Plant units. One of the sorbents tested was a magnesium hydroxide slurry produced from a wet flue gas desulfurization system waste stream, from a system that employs a Thiosorbic(regsign) Lime scrubbing process. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercial magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners, while the other three reagents were injected as slurries through air-atomizing nozzles into the front wall of upper furnace, either across from the nose of the furnace or across from the pendant superheater tubes. After completing the four one- to two-week tests, the most promising sorbents were selected for longer-term (approximately 25-day) full-scale tests. The longer-term tests are being conducted to confirm the effectiveness of the sorbents tested over extended operation and to determine balance-of-plant impacts. This reports presents the

  17. Processing of spent nickelcatalyst for fat recovery

    Directory of Open Access Journals (Sweden)

    NASIR Mohammad Ibraim

    2001-01-01

    Full Text Available Spent nickel catalyst (SNC has the potential of insulting the quality of the environment in a number of ways. Its disposal has a pollution effect. Optimum recovery of fat from SNC, could save the environment and reduce the oil loss. Hexane has been the solvent of choice for oil extraction. Alternative solvents considered to have been safer have been evaluated. Hexane, isopropanol, ethanol and heptane were examined using soxhlet extraction. While hexane is more efficient in oil recovery from SNC, isopropanol proved to be very good in clear separation of oil from waste material and also provides high solvent recovery compared to other solvents. Isopropanol extraction with chill separation of miscella into lower oil-rich phase, and an upper, solvent-rich recyclable phase save mush energy of vaporization for distilling. An aqueous extraction process with immiscible solvent assisted was tested. Solvent like hexane added to SNC, and water added later with continuous stirring. The mixture was stirred for about 30 minutes, prior to centrifugation. Aqueous process extracted less amount of oil compared to solvent extraction.

  18. Biological sulfuric acid transformation: Reactor design and process optimization.

    Science.gov (United States)

    Stucki, G; Hanselmann, K W; Hürzeler, R A

    1993-02-01

    As an alternative to the current disposal technologies for waste sulfuric acid, a new combination of recycling processes was developed. The strong acid (H(2)SO(4)) is biologically converted with the weak acid (CH(3)COOH) into two volatile weak acids (H(2)S, H(2)CO(3)) by sulfate-reducing bacteria. The transformation is possible without prior neutralization of the sulfuric acid. The microbially mediated transformation can be followed by physiochemical processes for the further conversion of the H(2)S.The reduction of sulfate to H(2)S is carried out under carbon-limited conditions at pH 7.5 to 8.5. A fixed-bed biofilm column reactor is used in conjunction with a separate gas-stripping column which was installed in the recycle stream. Sulfate, total sulfide, and the carbon substrate (in most cases acetate) were determined quantitatively. H(2)S and CO(2) are continually removed by stripping with N(2). Optimal removal is achieved under pH conditions which are adjusted to values below the pK(a)-values of the acids. The H(2)S concentration in the stripped gas was 2% to 8% (v/v) if H(2)SO(4) and CH(3)COOH are fed to the recycle stream just before the stripping column.Microbiol conversion rates of 65 g of sulfate reduced per liter of bioreactor volume per day are achieved and bacterial conversion efficiencies for sulfate of more than 95% can be maintained if the concentration of undissociated H(2)S is kept below 40 to 50 mg/L. Porous glass spheres, lava beads, and polyurethane pellets are useful matrices for the attachment of the bacterial biomass. Theoretical aspects and the dependence of the overall conversion performance on selected process parameters are illustrated in the Appendix to this article. PMID:18609554

  19. RECENT ADVANCES IN THE DEVELOPMENT OF THE HYBRID SULFUR PROCESS FOR HYDROGEN PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, D.

    2010-07-22

    Thermochemical processes are being developed to provide global-scale quantities of hydrogen. A variant on sulfur-based thermochemical cycles is the Hybrid Sulfur (HyS) Process, which uses a sulfur dioxide depolarized electrolyzer (SDE) to produce the hydrogen. In the HyS Process, sulfur dioxide is oxidized in the presence of water at the electrolyzer anode to produce sulfuric acid and protons. The protons are transported through a cation-exchange membrane electrolyte to the cathode and are reduced to form hydrogen. In the second stage of the process, the sulfuric acid by-product from the electrolyzer is thermally decomposed at high temperature to produce sulfur dioxide and oxygen. The two gases are separated and the sulfur dioxide recycled to the electrolyzer for oxidation. The Savannah River National Laboratory (SRNL) has been exploring a fuel-cell design concept for the SDE using an anolyte feed comprised of concentrated sulfuric acid saturated with sulfur dioxide. The advantages of this design concept include high electrochemical efficiency and small footprint compared to a parallel-plate electrolyzer design. This paper will provide a summary of recent advances in the development of the SDE for the HyS process.

  20. Pyrolysis processing for solid waste resource recovery

    Science.gov (United States)

    Serio, Michael A. (Inventor); Kroo, Erik (Inventor); Wojtowicz, Marek A. (Inventor); Suuberg, Eric M. (Inventor)

    2007-01-01

    Solid waste resource recovery in space is effected by pyrolysis processing, to produce light gases as the main products (CH.sub.4, H.sub.2, CO.sub.2, CO, H.sub.2O, NH.sub.3) and a reactive carbon-rich char as the main byproduct. Significant amounts of liquid products are formed under less severe pyrolysis conditions, and are cracked almost completely to gases as the temperature is raised. A primary pyrolysis model for the composite mixture is based on an existing model for whole biomass materials, and an artificial neural network models the changes in gas composition with the severity of pyrolysis conditions.

  1. [Recovery of consciousness: process-oriented approach].

    Science.gov (United States)

    Gusarova, S B

    2014-01-01

    Traditionally psychological neurorehabilitation of neurosurgical patients is provided subject to availability of clear consciousness and minimal potential to communicate verbally. Cognitive and emotional disorders, problems in social adaptation, neurotic syndromes are normally targets in such cases. We work with patients having survived severe brain damage being in different states of consciousness: vegetative state, minimal state of consciousness, mutism, confusion, posttraumatic Korsaroff syndrom. Psychologist considers recovery of consciousness as the target besides traditional tasks. Construction of communication with patient is central part of such job, where the patient remains unable to contact verbally, yet it is impossible to consider potential aphasia. This is a non-verbal "dialogue" with patient created by psychologist with gradual development and involving other people and objects of environment. Inline with modern neuroscientific achievements demonstrating ability to recognize by patients with severe brain injury (A. Owen, S. Laureys, M. Monti, M. Coleman, A. Soddu, M. Boly and others) we base upon psychological science, on psychotherapeutic approaches containing instruments inevitable to work with patients in altered states of consciousness and creation of non-verbal communication with patient (Jung, Reich, Alexander, Lowen, Keleman, Arnold and Amy Mindell, S. Tomandl, D. Boadella, A. Längle, P. Levin etc). This article will include 15 years of experience to apply Process-oriented approach by A. Mindell to recovery of consciousness of neurosurgical patients based on work with "minimal signals" (micro moves, breath, mimic reactions etc.), principle of feedback, psychosomatic resonance, empathy. PMID:24761599

  2. Thermal processes for heavy oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, A.K.; Sarathi, P.S.

    1993-11-01

    This status report summarizes the project BE11B (Thermal Processes for Heavy Oil Recovery) research activities conducted in FY93 and completes milestone 7 of this project. A major portion of project research during FY93 was concentrated on modeling and reservoir studies to determine the applicability of steam injection oil recovery techniques in Texas Gulf Coast heavy oil reservoirs. In addition, an in-depth evaluation of a steamflood predictive model developed by Mobil Exploration and Production Co. (Mobil E&P) was performed. Details of these two studies are presented. A topical report (NIPER-675) assessing the NIPER Thermal EOR Research Program over the past 10 years was also written during this fiscal year and delivered to DOE. Results of the Gulf Coast heavy oil reservoir simulation studies indicated that though these reservoirs can be successfully steamflooded and could recover more than 50% of oil-in-place, steamflooding may not be economical at current heavy oil prices. Assessment of Mobil E&P`s steamflood predictive model capabilities indicate that the model in its present form gives reasonably good predictions of California steam projects, but fails to predict adequately the performance of non-California steam projects.

  3. Uranium recovery from wet process phosphoric acid

    International Nuclear Information System (INIS)

    Improvement in the process for recovering uranium from wetprocess phosphoric acid solution derived from the acidulation of uraniferous phosphate ores by the use of two ion exchange liquidliquid solvent extraction circuits in which in the first circuit (A) the uranium is reduced to the uranous form; (B) the uranous uranium is recovered by liquid-liquid solvent extraction using a mixture of mono- and di-(Alkyl-phenyl) esters of orthophosphoric acid as the ion exchange agent; and (C) the uranium oxidatively stripped from the agent with phosphoric acid containing an oxidizing agent to convert uranous to uranyl ions, and in the second circuit (D) recovering the uranyl uranium from the strip solution by liquid-liquid solvent extraction using di(2ethylhexyl)phosphoric acid in the presence of trioctylphosphine oxide as a synergist; (E) scrubbing the uranium loaded agent with water; (F) stripping the loaded agent with ammonium carbonate, and (G) calcining the formed ammonium uranyl carbonate to uranium oxide, the improvement comprising: (1) removing the organics from the raffinate of step (B) before recycling the raffinate to the wet-process plant, and returning the recovered organics to the circuit to substantially maintain the required balance between the mono and disubstituted esters; (2) using hydogren peroxide as the oxidizing agent in step (C); (3) using an alkali metal carbonate as the stripping agent in step (F) following by acidification of the strip solution with sulfuric acid; (4) using some of the acidified strip solution as the scrubbing agent in step (E) to remove phosphorus and other impurities; and (5) regenerating the alkali metal loaded agent from step (F) before recycling it to the second circuit

  4. A novel process for low-sulfur biodiesel production from scum waste.

    Science.gov (United States)

    Ma, Huan; Addy, Min M; Anderson, Erik; Liu, Weiwei; Liu, Yuhuan; Nie, Yong; Chen, Paul; Cheng, Beijiu; Lei, Hanwu; Ruan, Roger

    2016-08-01

    Scum is an oil-rich waste from the wastewater treatment plants with a high-sulfur level. In this work, a novel process was developed to convert scum to high quality and low sulfur content biodiesel. A combination of solvent extraction and acid washing as pretreatment was developed to lower the sulfur content in the scum feedstock and hence improve biodiesel conversion yield and quality. Glycerin esterification was then employed to convert free fatty acids to glycerides. Moreover, a new distillation process integrating the traditional reflux distillation and adsorptive desulfurization was developed to further remove sulfur from the crude biodiesel. As a result, 70% of the filtered and dried scum was converted to biodiesel with sulfur content lower than 15ppm. The fatty acid methyl ester profiles showed that the refined biodiesel from the new process exhibited a higher quality and better properties than that from traditional process reported in previous studies. PMID:27241535

  5. New Syncrude recovery process : special report

    International Nuclear Information System (INIS)

    Syncrude Canada is the world's largest producer of light, sweet crude oil from oil sand. Syncrude is a joint venture owned by several companies, in which Imperial Oil is the largest participant. Syncrude's facility located near Fort McMurray, Alberta, is the single largest source of crude oil in Canada. Syncrude mines oil sand from a surface mine, extracts the raw bitumen from the sand using steam and hot water, and upgrades it into crude oil by fluid coking, hydroprocessing, hydrotreating and reblending. The Cold Lake plant, which is 100 per cent owned and operated by Imperial, is Canada's second largest source of crude oil production. Cyclic steam-stimulation (CSS) is the production process used at Cold Lake. CSS is a process in which steam is injected down the wellbore into the oil sand formation to heat the bitumen to reduce its viscosity. The heated bitumen is then pumped to the surface where it is processed at the processing plant and blended with lighter hydrocarbon liquids so that it can be shipped by pipeline. Recovery rates with this process have been improved from 17 per cent up to 25 per cent of the total bitumen in place. Additional processes are being studied to further improve extraction ratio and thus profitability. Imperial Oil is progressing with work on a $450 million development that would add proven reserves of 250 million barrels and increase bitumen production by an estimated 30,000 barrels per day. Also underway at Syncrude is work to increase production from its base plant through development of the North Mine by 1998. Expenditures related to this project are expected to be about $3350 million for mine development and about $125 million for new upgrading processes and equipment.3 figs

  6. A Survey of Novel Processes to Produce Ultra Low Sulfur Gasoline

    Institute of Scientific and Technical Information of China (English)

    Xu Yun; Long Jun; Shao Xinjun

    2003-01-01

    The restriction on sulfur level in gasoline has been increasingly tightened. The U.S.Tier Ⅱ regulation requires a reduction from average 340ppm to 30ppm from 2004 to 2008. Recently significant progress has been made in effective high sulfur removal, such as post treatment of FCC gasoline by selective hydrotreating, S Zorb sulfur removal technology, OATS process etc. The sulfur content of FCC gasoline can be deceased to less than 10ppm. With regard to gasoline pool composition in China, it is very important to look for effective desulfurization processes that are simple, straightforward, with less hydrogen consumption. Post-treatment of FCC gasoline is a preferred option. From the point of view of comprehensive utilization, alkylation, polymerization, isomerisation etc. can be added to desulfurization process to meet the requirement of ultra low sulfur, premium.

  7. SUMMARY REPORT: SULFUR OXIDES CONTROL TECHNOLOGY SERIES: FLUE GAS DESULFURIZATION - SPRAY DRYER PROCESS

    Science.gov (United States)

    Described spray dryer flue gas desulfurization (FGD), which is a throwaway process in which sulfur dioxide (SO2) is removed from flue gas by an atomized lime slurry [Ca(OH)2]. he hot flue gas dries the droplets to form a dry waste product, while the absorbent reacts with sulfur d...

  8. Development and Implementation of a Novel Sulfur Removal Process from H2S Containing Wastewaters.

    Science.gov (United States)

    Daigger, Glen T; Hodgkinson, Andrew; Aquilina, Simon; Fries, M Kim

    2015-07-01

    A novel process for removing sulfur from wastewater containing dissolved sulfide has been developed and implemented in a membrane bioreactor (MBR) process treating anaerobically pretreated industrial (pulp and paper) wastewater at the Gippsland Water Factory. Controlled oxygen addition to the first bioreactor zone (constituting 27.7% of the total bioreactor volume) to create oxygen-limiting conditions, followed by oxygen-sufficient conditions in the remaining zones of the bioreactor, provide the necessary conditions. Dissolved sulfide is oxidized to elemental sulfur in the first zone, and the accumulated sulfur is retained in the bioreactor mixed liquor suspended solids (MLSS) in the remaining zones. Accumulated sulfur is removed from the process in the waste activated sludge (WAS). Oxidation of dissolved sulfide to elemental sulfur reduces the associated process oxygen requirement by 75% compared to oxidation to sulfate. Microscopic examinations confirm that biological accumulation of elemental sulfur occurs. Process performance was analyzed during a nearly 2-year commissioning and optimization period. Addition of air in proportion to the process influent dissolved sulfide loading proved the most effective process control approach, followed by the maintenance of dissolved oxygen concentrations of 1.0 and 1.5 mg/L in the two downstream bioreactor zones. Sufficient oxygen is added for the stoichiometric conversion of dissolved sulfide to elemental sulfur. Enhanced biological phosphorus removal also occurred under these conditions, thereby simplifying supplemental phosphorus addition. These operating conditions also appear to lead to low and stable capillary suction time values for the MBR mixed liquor. PMID:26163497

  9. Measurement of mass transfer coefficient in direct contact sulfuric acid concentration for IS process

    International Nuclear Information System (INIS)

    Hydrogen is expected to serve as a clean secondary energy, because it can be manufactured from water, used in a variety of energy end-use sectors as fuel, and returned to water after burning. For the realization of hydrogen energy system, development of efficient and economical hydrogen production methods is required to meet the future huge demand of hydrogen. The Iodine-Sulfur (IS) process is a promising candidate of such hydrogen production methods, in which water reacts with iodine and sulfur dioxide to produce hydrogen iodide and sulfuric acid (Bunsen reaction) and the produced acids are then decomposed to produce hydrogen and oxygen, respectively. This study is concerned with the development of IS process equipment named direct contact sulfuric acid concentrator, in which gaseous mixture produced by thermal decomposition of sulfuric acid contacts directly with sulfuric acid solution. In the concentrator, the high temperature heat of the decomposed gas is recovered and used to concentrate sulfuric acid solution and, at the same time, the undecomposed sulfuric acid is condensed and separated from the decomposition products of sulfur dioxide and oxygen. Although the concept is very attractive from the viewpoint of the development of compact and efficient sulfuric acid concentrator, little is known on the heat and mass transfer relevant to the concentrator. Therefore, experimental methods were discussed to acquire the gas-phase mass transfer coefficient required for the optimal design of the concentrator. Assuming the use of wetted-wall column and also of the sulfuric acid of azeotropic composition as the test solution which could eliminate the liquid-phase mass transfer resistance, the column specification and the measurement conditions were determined by which flooding could be avoided and surface wetting could be assured, as well. (author)

  10. Progress and Application for Off-gas treatment Technology of SCOT Sulfur Recovery%SCOT硫回收尾气处理技术进展及应用

    Institute of Scientific and Technical Information of China (English)

    汪家铭; 林鸿伟

    2012-01-01

    SCOT ( Shell Claus Off-gas Treatment) sulfur recovery off-gas treatment technology was an off-gas purification process by which the number of the constructed plants having been built presently in the world was the maximal. Author has introduced the basic principle and process flow of the SCOT technology: has compared the technical characteristic of the low temperature SCOT, super-class SCOT, low sulfur SCOT with the conventional SCOT; has briefly described the technical progress of the SCOT process; has looked ahead its application prospect in China.%SCOT(Sell claus Off-gas Treating)硫回收尾气处理技术是目前世界上装置建设数量最多的尾气净化工艺。介绍了SCOT技术的基本原理和工艺流程;对比了低温SCOT、超级SCOT、低硫SCOT与常规SCOT的技术特点;简述了SCOT工艺的技术进展;展望了其在国内的应用前景。

  11. HYBRID SULFUR PROCESS REFERENCE DESIGN AND COST ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Gorensek, M.; Summers, W.; Boltrunis, C.; Lahoda, E.; Allen, D.; Greyvenstein, R.

    2009-05-12

    PBMR (Pty.) Ltd. in the RSA, with the Hybrid Sulfur (HyS) Process, under development by the Savannah River National Laboratory (SRNL) in the US as part of the NHI. This work was performed by SRNL, Westinghouse Electric Company, Shaw, PBMR (Pty) Ltd., and Technology Insights under a Technical Consulting Agreement (TCA). Westinghouse Electric, serving as the lead for the PBMR process heat application team, established a cost-shared TCA with SRNL to prepare an updated HyS thermochemical water-splitting process flowsheet, a nuclear hydrogen plant preconceptual design and a cost estimate, including the cost of hydrogen production. SRNL was funded by DOE under the NHI program, and the Westinghouse team was self-funded. The results of this work are presented in this Final Report. Appendices have been attached to provide a detailed source of information in order to document the work under the TCA contract.

  12. Processing of spent nickelcatalyst for fat recovery

    OpenAIRE

    NASIR Mohammad Ibraim

    2001-01-01

    Spent nickel catalyst (SNC) has the potential of insulting the quality of the environment in a number of ways. Its disposal has a pollution effect. Optimum recovery of fat from SNC, could save the environment and reduce the oil loss. Hexane has been the solvent of choice for oil extraction. Alternative solvents considered to have been safer have been evaluated. Hexane, isopropanol, ethanol and heptane were examined using soxhlet extraction. While hexane is more efficient in oil recovery from ...

  13. Recovery of nickel from spent NiO/Al2O3 catalyst through sulfuric acid leaching, precipitation and solvent extraction.

    Science.gov (United States)

    Nazemi, M K; Rashchi, F

    2012-05-01

    Effective recovery of nickel (Ni) from spent NiO/Al(2)O(3) catalyst in a simple hydrometallurgical route is suggested. Nickel recovery of 99.5% was achieved with sulfuric acid leaching. The leach liquor was partly neutralized and nickel ammonium sulfate was precipitated by adding ammonia. The nickel in the supernatant was concentrated by solvent extraction using D2EHPA and subsequently stripped back into sulfuric acid and returned to the precipitation stage. Necessary counter current extraction and stripping stages were determined in McCabe-Thiele diagrams. The suggested method appears simple and very effective in recovering nickel from spent catalysts from the petrochemical industry. PMID:21930525

  14. SULFURIC ACID REMOVAL PROCESS EVALUATION: LONG-TERM RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Gary M. Blythe; Richard McMillan

    2002-07-03

    The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The project is being co-funded by the U.S. DOE National Energy Technology Laboratory, under Cooperative Agreement DE-FC26-99FT40718, along with EPRI, the American Electric Power Company (AEP), FirstEnergy Corp., the Tennessee Valley Authority, and Dravo Lime, Inc. Sulfuric acid controls are becoming of increasing interest to power generators with coal-fired units for a number of reasons. Sulfuric acid is a Toxic Release Inventory species and can cause a variety of plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of selective catalytic reduction (SCR) for NO{sub x} control on many coal-fired plants, as SCR catalysts are known to further oxidize a portion of the flue gas SO{sub 2} to SO{sub 3}. The project previously tested the effectiveness of furnace injection of four different calcium-and/or magnesium-based alkaline sorbents on full-scale utility boilers. These reagents were tested during four one- to two-week tests conducted on two FirstEnergy Bruce Mansfield Plant (BMP) units. One of the sorbents tested was a magnesium hydroxide byproduct slurry produced from a modified Thiosorbic{reg_sign} Lime wet flue gas desulfurization system. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercial magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners, while the other three reagents were injected as slurries through air-atomizing nozzles inserted through the front wall of the upper furnace, either across from the nose of the furnace or across from the pendant superheater tubes. After completing the four one- to two-week tests, the most promising sorbents were selected for

  15. Recovery of vanadium from spent catalysts of sulfuric acid plant by using inorganic and organic acids: Laboratory and semi-pilot tests.

    Science.gov (United States)

    Erust, Ceren; Akcil, Ata; Bedelova, Zyuldyz; Anarbekov, Kuanysh; Baikonurova, Aliya; Tuncuk, Aysenur

    2016-03-01

    Catalysts are used extensively in industry to purify and upgrade various feeds and to improve process efficiency. These catalysts lose their activity with time. Spent catalysts from a sulfuric acid plant (main elemental composition: 5.71% V2O5, 1.89% Al2O3, 1.17% Fe2O3 and 61.04% SiO2; and the rest constituting several other oxides in traces/minute quantities) were used as a secondary source for vanadium recovery. Experimental studies were conducted by using three different leaching systems (citric acid with hydrogen peroxide, oxalic acid with hydrogen peroxide and sulfuric acid with hydrogen peroxide). The effects of leaching time, temperature, concentration of reagents and solid/liquid (S/L) ratio were investigated. Under optimum conditions (1:25 S/L ratio, 0.1M citric acid, 0.1M hydrogen peroxide, 50°C and 120min), 95% V was recovered in the presence of hydrogen peroxide in citric acid leaching. PMID:26711187

  16. Mechanism for the formation of elemental sulfur from aqueous sulfide in chemical and microbiological desulfurization processes

    Energy Technology Data Exchange (ETDEWEB)

    Steudel, R. [Technische Univ. Berlin (Germany). Inst. fuer Anorganische und Analytische Chemie

    1996-04-01

    A detailed reaction mechanism is proposed for the formation of crystalline elemental sulfur from aqueous sulfide by oxidation with transition-metal ions like V{sup 5}, Fe{sup 3}, Cu{sup 2}, etc. The first step is the formation of HS{center_dot} radicals by one-electron oxidation of HS{sup {minus}} ions. These radicals exist at pH values near 7 mainly as S{center_dot}{sup {minus}}. Their spontaneous decay results in the formation of the disulfide ion S{sub 2}{sup 2{minus}}. The further oxidation of disulfide either by S{center_dot}{sup {minus}} radicals or by the transition-metal ions yields higher polysulfide ions from which the homocyclic sulfur molecules S{sub 6}, S{sub 7}, and S{sub 8} are formed. In water these hydrophobic molecules form clusters which grow to droplets of liquid sulfur (sulfur sol). Depending on the composition of the aqueous phase, crystallization of the liquid sulfur as either {alpha}- or {beta}-S{sub 8} is rapid or delayed. Surfactants delay this solidification, while certain cations promote it. All these reactions are proposed to take place in desulfurization plants working by the Stretford, Sulfolin, Lo-Cat, SulFerox, or Bio-SR processes. In addition, the sulfur produced from sulfide by oxidizing sulfur bacteria is formed by the same mechanism, which now explains many observations made previously (including the formation of the byproducts thiosulfate, polythionates, and sulfate).

  17. Second law analysis of nuclear hydrogen production based on sulfuric acid decomposition process

    International Nuclear Information System (INIS)

    This paper discusses a thermochemical nuclear hydrogen producing process developed and evaluated using first and second laws of thermodynamics. The cycle is based on sulfuric acid decomposition process developed earlier. The process has been modified by producing mechanical power using additional primary energy as well as excess process heat generated within the cycle. The modified process has been closed using a sulfur dioxide electrochemical oxidizer cell and feasibility of its energy self sufficient operation has been proved. The second law efficiency of the cycle has been determined as 43.32 percent. It is found that the modified sulfuric acid decomposition section is improved by 14.8 percent compared to the basic process

  18. Amoco-US Environmental Protection Agency, pollution prevention project, Yorktown, Virginia: Yorktown refinery project workplan

    International Nuclear Information System (INIS)

    The report provides a detailed workplan for obtaining data and analyzing results for a 2-year pollution prevention study of Amoco Oil Company's Yorktown Virginia Refinery. The study was jointly sponsored as a cooperative effort of Amoco Corporation and the United States Environmental Protection Agency. The goals of the study include (1) a multi-media inventory of all releases entering the environment from the Refinery, (2) development of possible engineering options to reduce the releases, (3) analysis of each option in terms of release reduction potential, impact on human health risk, ecological impact, changes in future liability, etc. and (4) identification of obstacles and incentives for implementation of any of the options considered

  19. Amoco/Environmental Protection Agency Pollution Prevention Project, Yorktown refinery. Refinery release inventory. Final report

    International Nuclear Information System (INIS)

    The report volume summarizes physical data obtained during a 2-year pollution prevention study of Amoco Oil Company's Yorktown Virginia Refinery. The study was jointly sponsored as a cooperative effort of Amoco Corporation and the United States Environmental Protection Agency. A multi-media sampling program was used to identify potential pollution sources within the Refinery. Sampling and analysis included air, surface water, groundwater, and solid waste data. Public perceptions about environmental issues of concern in the vicinity of the Refinery were also surveyed. The inventory showed that nearly 99 percent of the releases were airborne at the facility. Most of the remainder involved land disposal of solid wastes. Specific sources of major pollutants are identified

  20. Toluene destruction in the Claus process by sulfur dioxide: A reaction kinetics study

    KAUST Repository

    Sinha, Sourab

    2014-10-22

    The presence of aromatics such as benzene, toluene, and xylene (BTX) as contaminants in the H2S gas stream entering Claus sulfur recovery units has a detrimental effect on catalytic reactors, where BTX forms soot particles and clogs and deactivates the catalysts. BTX oxidation, before they enter catalyst beds, can solve this problem. A theoretical investigation is presented on toluene oxidation by SO2. Density functional theory is used to study toluene radical (benzyl, o-methylphenyl, m-methylphenyl, and p-methylphenyl)-SO2 interactions. The mechanism begins with SO2 addition on the radical through one of the O atoms rather than the S atom. This exothermic reaction involves energy barriers of 4.8-6.1 kJ/mol for different toluene radicals. Thereafter, O-S bond scission takes place to release SO. The reaction rate constants are evaluated to facilitate process simulations. Among four toluene radicals, the resonantly stabilized benzyl radical exhibited lowest SO2 addition rate. A remarkable similarity between toluene oxidation by O2 and by SO2 is observed.

  1. Hydrogen production by the GA sulfur-iodine process: a progress report

    Energy Technology Data Exchange (ETDEWEB)

    Besenbruch, G.E.; McCorkle, K.H.; Norman, J.H.; O' Keefe, D.R.; Schuster, J.R.; Trester, P.W.; Yoshimoto, M.

    1980-05-01

    The progress of the overall total development effort of the General Atomic (GA) sulfur-iodine thermochemical water-splitting cycle over the last two years is summarized. The major accomplishments have been: significant improvements in the chemistry of the process; development, review, and revision of an engineering flowsheet, resulting in a thermal process efficiency of 47%; screening, identification, and testing of potential materials-of-construction for the corrosive process fluids; small-scale demonstration of the cycle in a closed loop under recycle conditions; installation of bench-scale equipment and demonstration of parts of the process in this system; and development of a conceptual, preliminary flowsheet for the GA sulfur-iodine cycle driven by solar energy. The results of the work carried out during the last two years have demonstrated that thermochemical water splitting by the sulfur-iodine cycle is a feasible process and have provided confidence that thermal efficiencies in the range of 50% are achievable.

  2. Effects of sulfurous acid on anodic process of gold electrode in thiourea solution

    Institute of Scientific and Technical Information of China (English)

    龙怀中; 舒万艮

    2003-01-01

    The electrochemistry behaviors of gold electrode in thiourea solution were studied by using electrochemical techniques, such as potentiodynamic, voltammogram and current step. A catalytical electrochemical-reduction mechanism was proposed to identify the anodic oxidation of gold in the thiourea solution. The results indicate that the decomposition of thiourea occurs when the electrode potential is higher than 640 mV. The addition of sulfurous acid presents a very positive effect on the anodic process of gold electrode. The anodic oxidation rate of gold is 5 times faster than that without sulfurous acid. The passivity of gold electrode is attributed to the accumulation of elemental sulfur on the surface of gold. The sulfurous acid reacts with the oxidation product ((SC(NH)NH2 )2 ) of thiourea, which can decrease the decomposition of thiourea and improves its stability.

  3. Rubber recovery from centrifuged natural rubber latex residue using sulfuric acid

    Directory of Open Access Journals (Sweden)

    Wirach Taweepreda

    2013-04-01

    Full Text Available Waste latex sludge from centrifuged residue, which is a null by-product of concentrated latex manufacturing, wasdigested to retrieve the rubber by using sulfuric acid. It was found that the acid concentration and digestion time have aneffect on the amount and purity of the retrieved rubber. Sulfuric acid at concentrations of more than 10% by weight with adigestion time of 48 hours completely digested waste latex sludge and gave rubber 10% by weight. The quality of the retrievedrubber was examined for Mooney viscosity (MV, plasticity retention index, nitrogen content, and ash content. The averagemolecular weight of the retrieved rubber, using gel permeation chromatography, was lower than that of normal natural rubber(NR which corresponds with the MV and initial plasticity (Po. The molecular structure from Fourier transform infraredspectroscopy (FT-IR indicated that the retrieved rubber surface is wet composed with hydroxyl functional ended group.The residue solution was evaporated and crystallized. The structure of crystals was determined using power X-ray diffractometer.

  4. Woodchip-sulfur based heterotrophic and autotrophic denitrification (WSHAD) process for nitrate contaminated water remediation.

    Science.gov (United States)

    Li, Rui; Feng, Chuanping; Hu, Weiwu; Xi, Beidou; Chen, Nan; Zhao, Baowei; Liu, Ying; Hao, Chunbo; Pu, Jiaoyang

    2016-02-01

    Nitrate contaminated water can be effectively treated by simultaneous heterotrophic and autotrophic denitrification (HAD). In the present study, woodchips and elemental sulfur were used as co-electron donors for HAD. It was found that ammonium salts could enhance the denitrifying activity of the Thiobacillus bacteria, which utilize the ammonium that is produced by the dissimilatory nitrate reduction to ammonium (DNRA) in the woodchip-sulfur based heterotrophic and autotrophic denitrification (WSHAD) process. The denitrification performance of the WSHAD process (reaction constants range from 0.05485 h(-1) to 0.06637 h(-1)) is better than that of sulfur-based autotrophic denitrification (reaction constants range from 0.01029 h(-1) to 0.01379 h(-1)), and the optimized ratio of woodchips to sulfur is 1:1 (w/w). No sulfate accumulation is observed in the WSHAD process and the alkalinity generated in the heterotrophic denitrification can compensate for alkalinity consumption by the sulfur-based autotrophic denitrification. The symbiotic relationship between the autotrophic and the heterotrophic denitrification processes play a vital role in the mixotrophic environment. PMID:26650451

  5. Treatment, recovery, and disposal processes for radioactive wastes

    International Nuclear Information System (INIS)

    Radioactive wastes handling and disposal are discussed in over 200 processes here. Isolation means for these wastes must withstand attack, essentially indefinitely, from the radioactive material and the chemical and physical stresses of the natural environment. Contents: Immobilization Techniques; Storage Containers; Water Removal and Concentration Processes; Chemical Treatments; Heat Treatments; Recovery and Recycling Processes; Processing Radioactive Gases; Waste Treatment Apparatus and Equipment

  6. From street to home : Community work in recovery process

    OpenAIRE

    Dodoo Nyamekyeh, Henry

    2011-01-01

    ABSTRACT: Henry Dodoo Nyamekyeh. From street to home (Community work in recovery process) Järvenpää, Autumn 2010, P. 53, 2 appendices. Language: English, Autumn 2010. Diaconia University of Applied Sciences, Diak-south, Järvenpää Unit, Degree Program in Social Services (DSS). Recovery is often defined as returning to a stable baseline or level of functioning. However many people, have experienced recovery as a transformative process in which the ―old self‖ is gradually let go off and ―new...

  7. Process improves C/sub 3//sup +/ recovery

    Energy Technology Data Exchange (ETDEWEB)

    Khan, S.A.

    1985-05-01

    This paper discusses DHX processing and how it can boost propane and heavier recovery from solution, refinery and natural gas to almost 100 percent. The process has been demonstrated at the Judy Creek plant of Esso Canada Resources, Ltd. A cryogenic expander plant was converted, after which recovery rose from 72 percent to 95 percent with 100% recovery recorded when operating at constant feed rates. Total investment for conversion was less than $750,000 to produce an extra 800 to 1,000 bpd of propane and heavier hydrocarbons.

  8. Complex processing of rubber waste through energy recovery

    OpenAIRE

    2015-01-01

    This article deals with the applied energy recovery solutions for complex processing of rubber waste for energy recovery. It deals specifically with the solution that could maximize possible use of all rubber waste and does not create no additional waste that disposal would be expensive and dangerous for the environment. The project is economically viable and energy self-sufficient. The outputs of the process could replace natural gas and crude oil products. The other part of the pro...

  9. Modeling of a Large-Scale High Temperature Regenerative Sulfur Removal Process

    DEFF Research Database (Denmark)

    Konttinen, Jukka T.; Johnsson, Jan Erik

    Regenerable mixed metal oxide sorbents are prime candidates for the removal of hydrogen sulfide from hot gasifier gas in the simplified integrated gasification combined cycle (IGCC) process. As part of the regenerative sulfur removal process development, reactor models are needed for scale-up. St...

  10. PROGRESS IN CATALYST AND PROCESS DEVELOPMENT FOR LOW SULFUR AND LOW AROMATICS DIESEL PRODUCTION

    Institute of Scientific and Technical Information of China (English)

    ZHOUYong; HANChong-ren

    2003-01-01

    The article includes three parts:①The development and performance of FH-DS catalyst for deep and ultra -deep distillate HDS;②The single stage HDS/HDA hydrotreating process for the production of low sulfur and low aromatics diesels from straight run and coker AGO by using highly active base metal catalyst at moderate pressure;③A two-stage aromatics saturation system utilizing noble metal catalyst in the second stage developed for production of low sulfur and low aromatics diesel from LCO.FDA catalyst developed by FRIPP has high activity for aromatics saturation together with high tolerance for sulfur and nitrogen in the feed.The process is effective in reducing density and increasing cetane number.

  11. Digital-image Based Numerical Simulation on Failure Process of High-sulfur Coal

    Directory of Open Access Journals (Sweden)

    Ye Junjian

    2013-01-01

    Full Text Available Crushing of high-sulfur coal was important for physical desulfurization, but there were little research on crushing mechanism. This paper combined digital image processing technology and rock failure process analysis system RFPA2D to simulate the failure process of high-sulfur coal in Pu'an of Guizhou under uniaxial compression, and discussed the influence of horizontal restraint, existence and different geometric distribution of pyrite particle on mechanical performance and failure process of high-sulfur coal. The numerical results indicated that without horizontal restraint the compressive strength of high-sulfur coal was lower and monomial dissociation of pyrite particle was more sufficient than that with horizontal restraint. The compressive strength of coal containing pyrite particle was larger than that of pure coal and there was stress concentration in upper and lower pyrite particle during failure process. When pyrite particle distributed in the middle position of a coal sample, the compressive strength was higher than that of the other three positions, but monomial dissociation of pyrite particle was more sufficient than that of the other three positions, and this was beneficial to the following desulfurization operation. The study had certain reference value for crushing mechanism, crushing process design, selection of breaking equipment and energy saving and consumption reduction.

  12. Sulfur Iodine Process Summary for the Hydrogen Technology Down-Selection

    Energy Technology Data Exchange (ETDEWEB)

    Benjamin Russ

    2009-05-01

    This report summarizes the sulfur-iodine (SI) thermochemical water splitting process for the purpose of supporting the process for evaluating and recommending a hydrogen production technology to deploy with the Next Generation Nuclear Plant (NGNP). This package provides the baseline process description as well as a comparison with the process as it was implemented in the Integrated Lab Scale (ILS) experiment conducted at General Atomics from 2006-2009.

  13. Stability of Spreading Processes with General Transmission and Recovery Times

    CERN Document Server

    Ogura, Masaki

    2016-01-01

    Although viral spreading processes taking place in networks are commonly analyzed using Markovian models in which both the transmission times and the recovery times follow exponential distributions, empirical studies show that, in most real scenarios, the distribution of these times are far from exponential. To overcome this limitation, we first introduce a generalized spreading model that allows for transmission and recovery times to follow arbitrary distributions within an arbitrary accuracy. In this context, we derive conditions for the generalized spreading process to converge towards the disease-free equilibrium (in other words, to eradicate the viral spread) without relying on mean-field approximations. Based on our results, we illustrate how the particular shape of the transmission/recovery distribution heavily influences the boundary of the stability region of the spread, as well as the decay rate inside this region. Therefore, modeling non-exponential transmission/recovery times observed in realistic...

  14. Recovery of plutonium by pyroredox processing

    International Nuclear Information System (INIS)

    Using pyrochemical oxidation and reduction, we have developed a process to recover the plutonium in impure scrap with less than 95% plutonium. This plutonium metal was further purified by pyrochemical electrorefining. During development of the procedures, depleted electrorefining anodes were processed, and over 80% of the plutonium was recovered as high-purity metal in one electrorefining cycle. Over 40 kg of plutonium has been recovered from 55 kg of impure anodes with our procedures. 6 refs., 7 figs., 4 tabs

  15. Associated rhenium recovery in molybdenite concentrates processing

    International Nuclear Information System (INIS)

    Salf of quaternary ammonium bases and different amines are used for rhenium extraction from solutions of wet dust and gas collection (WDC). Sorption processes of extraction and separation of rhenium and molybdenum are widely used when processing WDC solutions. Good results of technology of rhenium extraction were achieved due to directed synthesis of new low-base ionites, able to sorb rhenium selectively from molybdenum-containing solutions

  16. Recovery of plutonium by pyroredox processing

    International Nuclear Information System (INIS)

    Using pyrochemical oxidation and reduction, we have developed a process to recover the plutonium in impure scrap with less than 95% plutonium. This plutonium metal was further purified by pyrochemical electrorefining. During development of the procedures, depleted electrorefining anodes were processed, and over 80% of the plutonium was recovered as high-purity metal in one electrorefining cycle. Over 40 kg of plutonium has been recovered from 55 kg of impure anodes with our procedures. 6 refs., 2 figs., 5 tabs

  17. Pyrometallurgical processes for recovery of actinide elements

    Energy Technology Data Exchange (ETDEWEB)

    Battles, J.E.; Laidler, J.J.; McPheeters, C.C.; Miller, W.E.

    1994-01-01

    A metallic fuel alloy, nominally U-20-Pu-lOZr, is the key element of the Integral Fast Reactor (IFR) fuel cycle. Metallic fuel permits the use of an innovative, simple pyrometallurgical process, known as pyroprocessing, (the subject of this report), which features fused salt electrorefining of the spent fuel. Electrorefining separates the actinide elements from fission products, without producing a separate stream of plutonium. The plutonium-bearing product is contaminated with higher actinides and with a minor amount of rare earth fission products, making it diversion resistant while still suitable as a fuel material in the fast spectrum of the IFR core. The engineering-scale demonstration of this process will be conducted in the refurbished EBR-II Fuel Cycle Facility, which has entered the start-up phase. An additional pyrometallurgical process is under development for extracting transuranic (TRU) elements from Light Water Reactor (LWR) spent fuel in a form suitable for use as a feed to the IFR fuel cycle. Four candidate extraction processes have been investigated and shown to be chemically feasible. The main steps in each process are oxide reduction with calcium or lithium, regeneration of the reductant and recycle of the salt, and separation of the TRU product from the bulk uranium. Two processes, referred to as the lithium and salt transport (calcium reductant) processes, have been selected for engineering-scale demonstration, which is expected to start in late 1993. An integral part of pyroprocessing development is the treatment and packaging of high-level waste materials arising from the operations, along with the qualification of these waste forms for disposal in a geologic repository.

  18. Pyrometallurgical processes for recovery of actinide elements

    International Nuclear Information System (INIS)

    A metallic fuel alloy, nominally U-20-Pu-lOZr, is the key element of the Integral Fast Reactor (IFR) fuel cycle. Metallic fuel permits the use of an innovative, simple pyrometallurgical process, known as pyroprocessing, (the subject of this report), which features fused salt electrorefining of the spent fuel. Electrorefining separates the actinide elements from fission products, without producing a separate stream of plutonium. The plutonium-bearing product is contaminated with higher actinides and with a minor amount of rare earth fission products, making it diversion resistant while still suitable as a fuel material in the fast spectrum of the IFR core. The engineering-scale demonstration of this process will be conducted in the refurbished EBR-II Fuel Cycle Facility, which has entered the start-up phase. An additional pyrometallurgical process is under development for extracting transuranic (TRU) elements from Light Water Reactor (LWR) spent fuel in a form suitable for use as a feed to the IFR fuel cycle. Four candidate extraction processes have been investigated and shown to be chemically feasible. The main steps in each process are oxide reduction with calcium or lithium, regeneration of the reductant and recycle of the salt, and separation of the TRU product from the bulk uranium. Two processes, referred to as the lithium and salt transport (calcium reductant) processes, have been selected for engineering-scale demonstration, which is expected to start in late 1993. An integral part of pyroprocessing development is the treatment and packaging of high-level waste materials arising from the operations, along with the qualification of these waste forms for disposal in a geologic repository

  19. Business Process Based Database Recovery and Experimental Results

    Directory of Open Access Journals (Sweden)

    Pinaki Mitra

    2011-12-01

    Full Text Available In this research paper we have explained and presented the results of a novel database recovery method. Taking into account that most data servers today are becoming increasingly autonomic and business process oriented, there is a need to develop a new model where it is possible to do a database recovery based on the occurrence of a business process rather than non intuitive data like time, log file name/location or system change number. The advantage of this recovery model is that the user will no longer be required to remember non intuitive data like timestamp up to which the data has to be restored, log file name/location or system change number. Moreover the database server has built in intelligence to identify transaction behaviour, study the pattern among these batches and then storing recovery information specific to these business process to be used later for recovery. Another advantage is that the down time needed for restoring the database is reduced drastically since the trial and error approach followed by conventional data servers in the absence of accurate recovery information is eliminated. We have also simulated the Idea using JAVA API’s and Apache Derby and presented the experimental results for reference..

  20. Cultural points of resistance to the 12-Step recovery process.

    Science.gov (United States)

    Smith, D E; Buxton, M E; Bilal, R; Seymour, R B

    1993-01-01

    This article addresses some of the key issues in developing culturally relevant approaches to drug abuse treatment and recovery, using the HAFC/Glide African-American Extended Family Program as a positive example of effective cultural adaptability within recovery. Cultural points of resistance to the recovery process are also addressed, including the perception that 12-Step fellowships are exclusive and confused with religion, confusion over surrender versus powerlessness, and concerns about low self-esteem, dysfunctional family structure, communication difficulties, and institutionalized and internalized racism. The authors also focus on professional resistance in other countries, where different treatment approaches and philosophies block the acceptance of a recovery concept in general and the 12-Step process in particular. In explicating these issues, addiction is presented as a multicultural problem in need of multicultural solutions. The challenge is to adapt the process of recovery to all cultures and races, to counter stereotypes on all sides, and to eliminate the perception that recovery only works for addicts from the White mainstream. PMID:8483054

  1. Laboratory simulated slipstream testing of novel sulfur removal processes for gasification application

    International Nuclear Information System (INIS)

    The Wabash River Integrated Methanol and Power Production from Clean Coal Technologies (IMPPCCT) project is investigating an Early Entrance Coproduction Plant (EECP) concept to evaluate integrated electrical power generation and methanol production from coal and other carbonaceous feedstocks. Research, development and testing (RD and T) that is currently being conducted under the project is evaluating cost effective process systems for removing contaminants, particularly sulfur species, from the generated gas which contains mainly synthesis gas (syngas), CO2 and steam at concentrations acceptable for the methanol synthesis catalyst. The RD and T includes laboratory testing followed by bench-scale and field testing at the SG Solutions Gasification Plant located in West Terre Haute, Indiana. Actual synthesis gas produced by the plant was utilized at system pressure and temperature for bench-scale field testing. ConocoPhillips Company (COP) developed a sulfur removal technology based on a novel, regenerable sorbent - S Zorb trademark - to remove sulfur contaminants from gasoline at high temperatures. The sorbent was evaluated for its sulfur removal performance from the generated syngas especially in the presence of other components such as water and CO2 which often cause sorbent performance to decline over time. This publication also evaluates the performance of a regenerable activated carbon system developed by Nucon International, Inc. in polishing industrial gas stream by removing sulfur species to parts-per-billion (ppb) levels. (author)

  2. Equipment and obtention process of phosphorus-32 starting from sulfur-32

    International Nuclear Information System (INIS)

    In the National Institute of Nuclear Research, it is the Radioisotopes Production plant, which covers in the area of the medicine 70% approximately of the national market and it exports to some countries of Latin America (Technetium-99, iodine-131, Sm-153 among other). At the moment the plant has modern facilities and certified with the ISO-9001-2000 standard, this, gives trust to the clients as for the quality of its products. Besides the production of radioisotopes dedicated for the medical area, the work of the plant tends to be more enlarged every time, producing new radioisotopes not only but with medical purposes but also industrial and agricultural ones, such it is the case of the production of Phosphorus-32 (32P) that has applications with medical, industrial and in the agriculture purposes. The investigation studies from the prime matter (sulfur-32), sulfur purification, sulfur irradiation in the nuclear reactor and the obtaining process of 32P in a prototype, its took us to design and to build the obtaining process from 32P to more high level, which is presented in this work. To be able to select the obtaining method of 32 P that is presented it was necessary to study the methods that have been developed in the world, later on it was selected the way that is presented. In that way the physical and chemical properties of the sulfur were studied which is used as prime matter, the interest nuclear reaction was also studied to carry out the production of 32P by means of the realization of mathematical calculations of irradiation of the sulfur in TRIGA Mark lll nuclear reactor. Once the sulfur is irradiated, it is necessary to carry out the radiochemical separation of the 32P produced from the sulfur, for this, it was necessary to carry out experimental tests of this separation, later on it was developed a prototype where it was carried out this separation and finally it was developed the final equipment of production of 32P mainly composed of three systems

  3. Converting the Caetite mill process to enhance uranium recovery and expand production

    International Nuclear Information System (INIS)

    Full text: The Caetite uranium mill, located in Caetite - Bahia - Brazil, was commissioned in 2000 to produce about 880 000 pounds of uranium oxide per year from an uranium ore averaging 0.29% U3O8. The milling process starts with ore crushing followed by heap leaching with sulfuric acid solution to generate a pregnant leaching solution (PLS) containing about 2.5 g U3O8/L. Uranium separation and purification is carried out by solvent extraction with a kerosene solution of tertiary amine followed by stripping with an acidified sodium chloride aqueous solution. Uranium is precipitated as ammonium diuranate that is washed, filtered and dried. The historical average uranium recovery from this process is about 76%. As the Brazilian government has confirmed recently its plans to start building the third nuclear power plant in 2009, the Brazilian uranium production will have to double its capacity in the next two years. To fulfill the increasing demand, a change in the Caetite's milling process is being evaluated in order to not only increase the production but also the uranium recovery. In the new milling flow sheet the heap leaching process is changed to conventional tank agitated leaching of a - 0.59 mm ground ore slurry in sulfuric acid medium. Batch and pilot plant essays has shown that the uranium recovery increases to about 93% under the following conditions: grind size: -0.59 mm; slurry density: 65 solids wt%; leaching time: 4 hours; temperature: 60 deg C; oxidation potential: ∼500 mV; acid concentration in the PLS: ∼10 g/L. As the use of sodium chloride as the stripping agent has presented detrimental effects in the extraction/stripping process once all the process water is recycled, two alternative process are being evaluated for the uranium recovery from the PLS: (a) uranium peroxide precipitation at a controlled pH from a PLS that was firstly neutralized with ground limestone to pH 3.2 and filtered. Batch essays have shown good results with a final

  4. DEVELOPMENT OF INFRARED METHODS FOR CHARACTERIZATION OF INORGANIC SULFUR SPECIES RELATED TO INJECTION DESULFURIZATION PROCESSES

    Science.gov (United States)

    Current methods designed to control and reduce the amount of sulfur dioxide emitted into the atmosphere from coal-fired power plants and factories rely upon the reaction between SO2 and alkaline earth compounds and are called flue gas desulfurization (FGD) processes. Of these met...

  5. Chapter 7: Spills - AMOCO CADIZ (France), Bhopal (India), Chernobyl (U.S.S.R.)

    International Nuclear Information System (INIS)

    AMOCO CADIZ, Bhopal and Chernobyl represent different levels of spill assessment and response. The impact sequence progresses from slow, barely lethal aquatic impact, through a sudden locally killing impact (Bhopal), to a massive potentially global disaster with long-term consequences (Chernobyl). The response sequence documented progresses from a planned binational emergency program to a completely overwhelmed virtually non-existing capability (Bhobal). At Chernobyl the response team had to scope with an unprecedented, globally threatening emergency requiring novel initiatives quickly, and with an international need-to-know. There are benefits for risk prediction and response planning in comparing spills. (DG)

  6. Characteristics and adaptability of iron- and sulfur-oxidizing microorganisms used for the recovery of metals from minerals and their concentrates.

    Science.gov (United States)

    Rawlings, Douglas E

    2005-05-01

    Microorganisms are used in large-scale heap or tank aeration processes for the commercial extraction of a variety of metals from their ores or concentrates. These include copper, cobalt, gold and, in the past, uranium. The metal solubilization processes are considered to be largely chemical with the microorganisms providing the chemicals and the space (exopolysaccharide layer) where the mineral dissolution reactions occur. Temperatures at which these processes are carried out can vary from ambient to 80 degrees C and the types of organisms present depends to a large extent on the process temperature used. Irrespective of the operation temperature, biomining microbes have several characteristics in common. One shared characteristic is their ability to produce the ferric iron and sulfuric acid required to degrade the mineral and facilitate metal recovery. Other characteristics are their ability to grow autotrophically, their acid-tolerance and their inherent metal resistance or ability to acquire metal resistance. Although the microorganisms that drive the process have the above properties in common, biomining microbes usually occur in consortia in which cross-feeding may occur such that a combination of microbes including some with heterotrophic tendencies may contribute to the efficiency of the process. The remarkable adaptability of these organisms is assisted by several of the processes being continuous-flow systems that enable the continual selection of microorganisms that are more efficient at mineral degradation. Adaptability is also assisted by the processes being open and non-sterile thereby permitting new organisms to enter. This openness allows for the possibility of new genes that improve cell fitness to be selected from the horizontal gene pool. Characteristics that biomining microorganisms have in common and examples of their remarkable adaptability are described. PMID:15877814

  7. Characteristics and adaptability of iron- and sulfur-oxidizing microorganisms used for the recovery of metals from minerals and their concentrates

    Directory of Open Access Journals (Sweden)

    Rawlings Douglas E

    2005-05-01

    Full Text Available Abstract Microorganisms are used in large-scale heap or tank aeration processes for the commercial extraction of a variety of metals from their ores or concentrates. These include copper, cobalt, gold and, in the past, uranium. The metal solubilization processes are considered to be largely chemical with the microorganisms providing the chemicals and the space (exopolysaccharide layer where the mineral dissolution reactions occur. Temperatures at which these processes are carried out can vary from ambient to 80°C and the types of organisms present depends to a large extent on the process temperature used. Irrespective of the operation temperature, biomining microbes have several characteristics in common. One shared characteristic is their ability to produce the ferric iron and sulfuric acid required to degrade the mineral and facilitate metal recovery. Other characteristics are their ability to grow autotrophically, their acid-tolerance and their inherent metal resistance or ability to acquire metal resistance. Although the microorganisms that drive the process have the above properties in common, biomining microbes usually occur in consortia in which cross-feeding may occur such that a combination of microbes including some with heterotrophic tendencies may contribute to the efficiency of the process. The remarkable adaptability of these organisms is assisted by several of the processes being continuous-flow systems that enable the continual selection of microorganisms that are more efficient at mineral degradation. Adaptability is also assisted by the processes being open and non-sterile thereby permitting new organisms to enter. This openness allows for the possibility of new genes that improve cell fitness to be selected from the horizontal gene pool. Characteristics that biomining microorganisms have in common and examples of their remarkable adaptability are described.

  8. Diffusion kinetics of metal recovery biosorption processes

    International Nuclear Information System (INIS)

    The uptake of heavy metals and radionuclides by alginate beads was studied to determine kinetic and mass transport parameters of this biosorption process. The kinetics of cadmium and uranyl ion uptake by calcium alginate were assessed using a mathematical expression derived for evaluation of hyperbolic type biosorption isotherms. Removal efficiencies were evaluated under varying solution conditions of initial solute concentration, pH, temperature and the presence of selected cations. The maximum rate of sorption was found to be 241.7 and 978.8 mg/L/min for uranium and cadmium, respectively. Based upon Fick's Second Law, a quantitative description of the mass transfer mechanism for these biosorption processes was developed, and diffusion coefficients determined for the sorption of UO2+2 and Cd2+ by calcium alginate gel beads

  9. Measurements of plutonium residues from recovery processes

    International Nuclear Information System (INIS)

    Conventional methods of nondestructive assay (NDA) have accurately assayed the plutonium content of many forms of relatively pure and homogeneous bulk items. However, physical and chemical heterogeneities and the high and variable impurity levels of many categories of processing scrap bias the conventional NDA results. The materials also present a significant challenge to the assignment of reference values to process materials for purposes of evaluating the NDA methods. A recent study using impure, heterogeneous, pyrochemical residues from americium molten salt extraction (MSE) has been aimed at evaluating NDA assay methods based on conventional gamma-ray and neutron measurement techniques and enhanced with analyses designed to address the problems of heterogeneities and impurities. The study included a significant effort to obtain reference values for the MSE spent salts used in the study. Two of the improved NDA techniques, suitable for in-line assay of plutonium in bulk, show promise for timely in-process assays for one of the most difficult pyrochemical residues generated as well as for other impure heterogeneous scrap categories. 12 refs., 4 figs., 5 tabs

  10. Experimental research of sulfur mineral recovery from a certain separated zinc tailings%某选锌尾矿回收硫矿物试验研究

    Institute of Scientific and Technical Information of China (English)

    杨俊彦; 叶雪均; 秦华伟

    2013-01-01

    To recycle sulfur mineral from a certain separated zinc tailings,in view of high content of pyrrhotite in tailings,the experiments separately involving magnetic separation after flotation as well as flotation after magnetic separation were conducted.Both two schemes consisted of a roughing,a scavenging,three concentration and sulfuric acid activation.Through the closed-circuit experiment involving magnetic separation after flotation,sulphur concentrate with sulfur grade of 35.08% and sulfur recovery rate of 93.65% was obtained.Through the closed-circuit experiment involving flotation after magnetic separation,sulphur concentrate with sulfur grade of 33.92% and sulfur recovery rate of 92.15% was obtained.The contrast results showed that the scheme involving magnetic separation after flotation was superior.%为回收某尾矿中的硫矿物,针对尾矿中磁黄铁矿含量高的特点,分别进行了先浮后磁流程和先磁后浮流程试验.2个方案均采用一粗一扫三精流程和硫酸活化,通过先浮后磁闭路试验,得到了综合硫精矿硫品位为35.08%,硫回收率为93.65%的试验结果;通过先磁后浮闭路试验,得到了综合硫精矿硫品位为33.92%,硫回收率为92.15%的试验结果.通过试验证明,先浮后磁方案较佳.

  11. World sulfur production: Petroleum derived as of January 1, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    Data are presented on world sulfur production by company within each country. The table lists the source of the sulfur (refinery gases, natural gas, acid gas, sour gas, oil sands, associated gas, or resid asphalt), the type of process used to recovery the sulfur, plant design capacity, and production. Processes include Claus, chlorination, Scot, Sulfinol, Sulfreen, modified Claus, bed absorption, MDEA-LoCat, Selectox, Parsons, SNEA, Comprimo, Uhde, Stretford, and Wellman-Lord.

  12. An environmentally friendly process for the recovery of valuable metals from spent refinery catalysts.

    Science.gov (United States)

    Rocchetti, Laura; Fonti, Viviana; Vegliò, Francesco; Beolchini, Francesca

    2013-06-01

    The present study dealt with the whole valorization process of exhaust refinery catalysts, including metal extraction by ferric iron leaching and metal recovery by precipitation with sodium hydroxide. In the leaching operation the effects on metal recovery of the concentration and kind of acid, the concentration of catalyst and iron (III) were determined. The best operating conditions were 0.05 mol L(-1) sulfuric acid, 40 g L(-1) iron (III), 10% catalyst concentration; almost complete extraction of nickel and vanadium, and 50%extraction efficiency of aluminium and less than 20% for molybdenum. Sequential precipitation on the leach liquor showed that it was not possible to separate metals through such an approach and a recovery operation by means of a single-stage precipitation at pH 6.5 would simplify the procedures and give a product with an average content of iron (68%), aluminium (13%), vanadium (11%), nickel (6%) and molybdenum (1%) which would be potentially of interest in the iron alloy market. The environmental sustainability of the process was also assessed by means of life cycle assessment and yielded an estimate that the highest impact was in the category of global warming potential with 0.42 kg carbon dioxide per kg recovered metal. PMID:23393098

  13. Actinide recovery techniques utilizing electromechanical processes

    International Nuclear Information System (INIS)

    Under certain conditions, the separation of actinides using electromechanical techniques may be an effective means of residue processing. The separation of granular mixtures of actinides and other materials discussed in this report is based on appreciable differences in the magnetic and electrical properties of the actinide elements. In addition, the high density of actinides, particularly uranium and plutonium, may render a simultaneous separation based on mutually complementary parameters. Both high intensity magnetic separation and electrostatic separation have been investigated for the concentration of an actinide waste stream. Waste stream constituents include an actinide metal alloy and broken quartz shards. The investigation of these techniques is in support of the Integral Fast Reactor (IFR) concept currently being developed at Argonne National Laboratory under the auspices of the Department of Energy

  14. A chemical cleaning process with Cerium (IV)-sulfuric acid

    International Nuclear Information System (INIS)

    A chemical cleaning process with a high decontamination factor (DF) is requested for decommissioning. Usually, the process should be qualified with the features, such as the feasibility of treating large or complicated form waste, the minimization of secondary waste. Therefore, a powerful technique of redox decontamination process with Ce+4/Ce+3 has been studied at INER. First, the redox of cerium ion with electrolytic method was developed. Two kinds of home-made electrolyzer were used. One is with an ion-exchange membrane, and the other one is with a ceramic separator. Second, factors influencing the decontamination efficiency, such as the concentration of Ce+4, regeneration current density, temperature, acidity of solution were all studied experimentally, and the optimum conditions were specified too. Third, the liquid waste recycling and treatment were developed with electrodialysis and ion-exchange absorption methods. Finally, the hot test was proceeded with the contaminated metals from DCR of nuclear facility. (author)

  15. The GA sulfur-iodine water-splitting process - A status report

    Science.gov (United States)

    Besenbruch, G. E.; Chiger, H. D.; Mccorkle, K. H.; Norman, J. H.; Rode, J. S.; Schuster, J. R.; Trester, P. W.

    1981-01-01

    The development of a sulfur-iodine thermal water splitting cycle is described. The process features a 50% thermal efficiency, plus all liquid and gas handling. Basic chemical investigations comprised the development of multitemperature and multistage sulfuric acid boost reactors, defining the phase behavior of the HI/I2/H2O/H3PO4 mixtures, and development of a decomposition process for hydrogen iodide in the liquid phase. Initial process engineering studies have led to a 47% efficiency, improvements of 2% projected, followed by coupling high-temperature solar concentrators to the splitting processes to reduce power requirements. Conceptual flowsheets developed from bench models are provided; materials investigations have concentrated on candidates which can withstand corrosive mixtures at temperatures up to 400 deg K, with Hastelloy C-276 exhibiting the best properties for containment and heat exchange to I2.

  16. Process Control for Precipitation Prevention in Space Water Recovery Systems

    Science.gov (United States)

    Sargusingh, Miriam; Callahan, Michael R.; Muirhead, Dean

    2015-01-01

    The ability to recover and purify water through physiochemical processes is crucial for realizing long-term human space missions, including both planetary habitation and space travel. Because of their robust nature, rotary distillation systems have been actively pursued by NASA as one of the technologies for water recovery from wastewater primarily comprised of human urine. A specific area of interest is the prevention of the formation of solids that could clog fluid lines and damage rotating equipment. To mitigate the formation of solids, operational constraints are in place that limits such that the concentration of key precipitating ions in the wastewater brine are below the theoretical threshold. This control in effected by limiting the amount of water recovered such that the risk of reaching the precipitation threshold is within acceptable limits. The water recovery limit is based on an empirically derived worst case wastewater composition. During the batch process, water recovery is estimated by monitoring the throughput of the system. NASA Johnson Space Center is working on means of enhancing the process controls to increase water recovery. Options include more precise prediction of the precipitation threshold. To this end, JSC is developing a means of more accurately measuring the constituent of the brine and/or wastewater. Another means would be to more accurately monitor the throughput of the system. In spring of 2015, testing will be performed to test strategies for optimizing water recovery without increasing the risk of solids formation in the brine.

  17. A Tire-Sulfur Hybrid Adsorption Denitrification (T-SHAD) process for decentralized wastewater treatment.

    Science.gov (United States)

    Krayzelova, Lucie; Lynn, Thomas J; Banihani, Qais; Bartacek, Jan; Jenicek, Pavel; Ergas, Sarina J

    2014-09-15

    Nitrogen discharges from decentralized wastewater treatment (DWT) systems contribute to surface and groundwater contamination. However, the high variability in loading rates, long idle periods and lack of regular maintenance presents a challenge for biological nitrogen removal in DWT. A Tire-Sulfur Hybrid Adsorption Denitrification (T-SHAD) process was developed that combines nitrate (NO3(-)) adsorption to scrap tire chips with sulfur-oxidizing denitrification. This allows the tire chips to adsorb NO3(-) when the influent loading exceeds the denitrification capacity of the biofilm and release it when NO3(-) loading rates are low (e.g. at night). Three waste products, scrap tire chips, elemental sulfur pellets and crushed oyster shells, were used as a medium in adsorption, leaching, microcosm and up-flow packed bed bioreactor studies of NO3(-) removal from synthetic nitrified DWT wastewater. Adsorption isotherms showed that scrap tire chips have an adsorption capacity of 0.66 g NO3(-)-N kg(-1) of scrap tires. Leaching and microcosm studies showed that scrap tires leach bioavailable organic carbon that can support mixotrophic metabolism, resulting in lower effluent SO4(2-) concentrations than sulfur oxidizing denitrification alone. In column studies, the T-SHAD process achieved high NO3(-)-N removal efficiencies under steady state (90%), variable flow (89%) and variable concentration (94%) conditions. PMID:24922353

  18. A novel process to treat spent petroleum catalyst using sulfur-oxidizing lithotrophs.

    Science.gov (United States)

    Kim, Dong J; Mishra, Debaraj; Ahn, Jong G; Chaudhury, Gautam R; Ralph, David E

    2009-12-01

    A novel process was developed using sulfur-oxidizing bacteria to extract metal values like Ni, V and Mo from spent petroleum catalyst. Bacteria were grown in elemental sulfur media for five day and after filtering, the filtrate was used for leaching purpose. Effect of different parameters such as contact time, particle size, pulp density and lixiviant composition were studied to find out the extent of metal leaching during the leaching process. XRD analysis proved the existence of V in oxide form, Ni in sulfide form, Mo both in oxide as well as sulfide forms, and sulfur in elemental state only. In all the cases studied Ni and V showed higher leaching efficiency compared to Mo. The low Mo leaching rate may be either due to formation of impervious sulfur layer or refractoriness of sulfides or both. Leaching kinetics followed dual rate, initial faster followed by slower. Dissolution mechanism was explained on the basis of both surface and pore diffusion rate. The leaching kinetics followed 1st order reaction rate. Finally, multiple linear regression analysis was carried out to compare the observed and calculated leaching percentage values for three metals. PMID:20183517

  19. Processes for preparing carbon fibers using gaseous sulfur trioxide

    Science.gov (United States)

    Barton, Bryan E.; Lysenko, Zenon; Bernius, Mark T.; Hukkanen, Eric J.

    2016-01-05

    Disclosed herein are processes for preparing carbonized polymers, such as carbon fibers, comprising: sulfonating a polymer with a sulfonating agent that comprises SO.sub.3 gas to form a sulfonated polymer; treating the sulfonated polymer with a heated solvent, wherein the temperature of said solvent is at least 95.degree. C.; and carbonizing the resulting product by heating it to a temperature of 500-3000.degree. C.

  20. Process modelling and heat management of the solar hybrid sulfur cycle

    OpenAIRE

    Guerra Niehoff, Alejandro; Bayer Botero, Nicolas; Acharya, Anirudh; Thomey, Dennis; Roeb, Martin; Sattler, Christian; Pitz-Paal, Robert

    2015-01-01

    Thermochemical cycles for water splitting are considered as a promising example of emission-free routes for large-scale hydrogen production e with potentially higher efficiencies and lower costs compared to low temperature electrolysis of water. The hybrid esulfur cycle was chosen as one of the most promising cycles from the ‘sulfur family’ of processes. A process model has been established to study the main parameters influencing efficiency with specific attention paid to dynamic effects whe...

  1. Pretreatment of rice straw with combined process using dilute sulfuric acid and aqueous ammonia

    OpenAIRE

    Kim, Sung Bong; Lee, Sang Jun; Lee, Ju Hun; Jung, You Ree; Thapa, Laxmi Prasad; Kim, Jun Seok; Um, Youngsoon; Park, Chulhwan; Kim, Seung Wook

    2013-01-01

    Background Use of lignocellulosic biomass has received attention lately because it can be converted into various versatile chemical compounds by biological processes. In this study, a two-step pretreatment with dilute sulfuric acid and aqueous ammonia was performed efficiently on rice straw to obtain fermentable sugar. The soaking in aqueous ammonia process was also optimized by a statistical method. Results Response surface methodology was employed. The determination coefficient (R2) value w...

  2. Sulfur behaviour on stainless steel melting by single-slag process

    International Nuclear Information System (INIS)

    A consideration is given to desulfurizing process during melting stainless steel type 08-12Kh18N10T according to a single-slag variant of melting technology. Wastes of abrasive metal machining and worn-out equipment from chemical plants are shown to be highly contaminated with sulfur and cannot be remelted by the above-mentioned process. A new variant of two-slag melting technology was successfully tested. 4 refs

  3. Data warehousing methods and processing infrastructure for brain recovery research.

    Science.gov (United States)

    Gee, T; Kenny, S; Price, C J; Seghier, M L; Small, S L; Leff, A P; Pacurar, A; Strother, S C

    2010-09-01

    In order to accelerate translational neuroscience with the goal of improving clinical care it has become important to support rapid accumulation and analysis of large, heterogeneous neuroimaging samples and their metadata from both normal control and patient groups. We propose a multi-centre, multinational approach to accelerate the data mining of large samples and facilitate data-led clinical translation of neuroimaging results in stroke. Such data-driven approaches are likely to have an early impact on clinically relevant brain recovery while we simultaneously pursue the much more challenging model-based approaches that depend on a deep understanding of the complex neural circuitry and physiological processes that support brain function and recovery. We present a brief overview of three (potentially converging) approaches to neuroimaging data warehousing and processing that aim to support these diverse methods for facilitating prediction of cognitive and behavioral recovery after stroke, or other types of brain injury or disease. PMID:21175009

  4. Hydrogen production by the GA sulfur-iodine process: a progress report

    Energy Technology Data Exchange (ETDEWEB)

    Besenbruch, G.E.; McCorkle, K.H.; Norman, J.H.; O' Keefe, D.R.; Schuster, J.R.; Yoshimoto, M.

    1980-03-01

    A summary of the progress of the overall total development effort of the General Atomic (GA) sulfur-iodine thermochemical water-splitting cycle over the last two years is reported. The major accomplishments have been the following: (1) Significant improvements in the chemistry of the process. (2) Development, review, and revision of an engineering flowsheet, resulting in a thermal process efficiency of 47%. (3) Screening, identification, and testing of potential materials-of-construction for the corrosive process fluids. (4) Small-scale demonstration of the cycle in a closed loop under recycle conditions. (5) Installation of bench-scale equipment and demonstration of parts of the process in this system. (6) Development of a conceptual, preliminary flowsheet for the GA sulfur-iodine cycle driven by solar energy. The results of the work carried out during the last two years have demonstrated that thermochemical water splitting by the sulfur-iodine cycle is a feasible process and have provided confidence that thermal efficiencies in the range of 50% are achievable.

  5. Analysis of Failure of Steam Return Line for Liquid Sulfur Pump in Sulfur Recovery Unit%硫黄回收装置液硫泵蒸汽回流管失效分析

    Institute of Scientific and Technical Information of China (English)

    陈勇

    2012-01-01

    The steam return line for liquid sulfur pump in the sulfur recovery unit fractured many times. The fractures were located in the welded joints, and the cracks originated from weld and promulgated circumferentially to the base metal of elbow. The length of cracking was as long as haft circumference. The fractured elbow of steam retum line was analyzed by macro testing, composition analysis, metallographic analysis and energy dispersion spectrum (EDS). The corrosion mechanisms and testing results were studied based upon process conditions. It is concluded from analysis that the main culprits of fracture of the steam return line are poor welding quality, un - uniform metallographic structure and unsatisfactory heat treatment, which resulted in high residue stress in welds and stress corrosion cracking (SCC) in polythionic acid environment. It is recommended to use new materials, reduce SSC, control welding quality and eliminate welding defects.%摘要:硫黄回收装置液硫输送泵的蒸汽回流管多次发生开裂,开裂位置均为焊接接头部位,裂纹起源于焊缝焊趾,沿环向扩展,最终扩展至弯头母材,开裂长度达半周以上;外弯处焊缝错边量约1mm,内弯处存在整圈1.5mm高的未熔合。文章对液硫输送泵蒸汽回流管的开裂弯头进行了宏观检验、成分分析、金相检验和能谱分析,并结合工艺条件、对腐蚀机理和检测结果进行了失效分析,通过分析得出蒸汽回流管开裂主要是由于焊接质量不高、金相组织不均匀和热处理不好等原因导致焊接结构存在高残余应力,这些残余应力在连多硫酸环境下发生应力腐蚀开裂所至;提出了更换材质减少应力腐蚀开裂和控制焊接成型质量避免焊接缺陷的建议。

  6. SSHT Process-a Low Cost Solution for Low Sulfur and Low Aromatics Diesel

    Institute of Scientific and Technical Information of China (English)

    Gao Xiaodong; Nie Hong; Shi Yulin; Shi Yahua; Li Dadong

    2003-01-01

    The need for cleaner fuels has resulted in a continuing worldwide trend to reduce diesel sulfur and aromatics. There are many approaches to reducing sulfur and aromatics in diesel. Most of them have a common drawback of high cost because of adopting two stages of hydrotreating and using noble-metal catalyst, especially for reducing aromatics. The attempt to resolve this issue has led to the recent development of the Single Stage Hydrotreating (SSHT) process by Research Institute of Petroleum Processing (RIPP), SINOPEC.The SSHT process is a single-stage hydrotreating technology for producing low sulfur and low aromatics diesel. The process uses one or two non-noble-metal catalysts system and operates at moderate pressure. When revamping an existing unit to meet low aromatics diesel specification, the only thing to do is to add a reactor or replace the existing reactor, In pilot plant tests, the SSHT technology has successfully treated SRGO (Straight Run Gas Oil), LCO (Light Cycle Oil) or the blend of them. It is shown that by using the SSHT process diesel with sulfur of 30 ppm and aromatics of 15 m% can be produced from Middle-East SRGO and diesel with aromatics content of 25 m% can be produced from cracked feed, such as FCC-LCO. High diesel yield and cetane number gain (from cracked feed stocks) give the SSHT technology a performance advantage compared to conventional hydrocracking and hydrotreating processes.The lower investment and operating cost is another advantage. The first commercial application of the SSHT technology has been in operation since September 2001.

  7. Phosphorus recovery from sewage sludge ash through an electrodialytic process

    DEFF Research Database (Denmark)

    Guedes, Paula; Couto, Nazare; Ottosen, Lisbeth M.;

    2014-01-01

    The electrodialytic separation process (ED) was applied to sewage sludge ash (SSA) aiming at phosphorus (P) recovery. As the SSA may have high heavy metals contents, their removal was also assessed. Two SSA were sampled, one immediately after incineration (SA) and the other from an open deposit (SB...

  8. Washing processes for plutonium recovery from solid wastes

    International Nuclear Information System (INIS)

    The recovery of plutonium from primary wastes by means of washing processes has been investigated and demonstrated on a laboratory scale. For both ecological as well as economic reasons it is reasonable to recover plutonium from these wastes. It can be concluded that with the correct coordination of washing procedures with waste composition, the bulk of plutonium can be recovered with very little expenditure

  9. ASPEN Plus Simulation of CO2 Recovery Process

    Energy Technology Data Exchange (ETDEWEB)

    Charles W. White III

    2003-09-30

    ASPEN Plus simulations have been created for a CO{sub 2} capture process based on adsorption by monoethanolamine (MEA). Three separate simulations were developed, one each for the flue gas scrubbing, recovery, and purification sections of the process. Although intended to work together, each simulation can be used and executed independently. The simulations were designed as template simulations to be added as a component to other more complex simulations. Applications involving simple cycle or hybrid power production processes were targeted. The default block parameters were developed based on a feed stream of raw flue gas of approximately 14 volume percent CO{sub 2} with a 90% recovery of the CO{sub 2} as liquid. This report presents detailed descriptions of the process sections as well as technical documentation for the ASPEN simulations including the design basis, models employed, key assumptions, design parameters, convergence algorithms, and calculated outputs.

  10. On the optimal design of the disassembly and recovery processes

    International Nuclear Information System (INIS)

    This paper tackles the problem of the optimal design of the recovery processes of the end-of-life (EOL) electric and electronic products, with a special focus on the disassembly issues. The objective is to recover as much ecological and economic value as possible, and to reduce the overall produced quantities of waste. In this context, a medium-range tactical problem is defined and a novel two-phased algorithm is presented for a remanufacturing-driven reverse supply chain. In the first phase, we propose a multicriteria/goal-programming analysis for the identification and the optimal selection of the most 'desirable' subassemblies and components to be disassembled for recovery, from a set of different types of EOL products. In the second phase, a multi-product, multi-period mixed-integer linear programming (MILP) model is presented, which addresses the optimization of the recovery processes, while taking into account explicitly the lead times of the disassembly and recovery processes. Moreover, a simulation-based solution approach is proposed for capturing the uncertainties in reverse logistics. The overall approach leads to an easy-to-use methodology that could support effectively middle level management decisions. Finally, the applicability of the developed methodology is illustrated by its application on a specific case study

  11. Exergy Analysis of the Process of Thermal Decomposition of Phosphogypsum to Lime and Sulfur Dioxide

    Directory of Open Access Journals (Sweden)

    Lubka Atanasova

    2002-09-01

    Full Text Available The wet process phosphoric acid is produced by decomposition of phosphate raw materials with sulfuric acid. This gives a large amount of waste product - phosphogypsum. The thermochemical decomposition of phosphogypsum to lime and sulfur dioxide provides possibilities to utilize its main components CaO and S and, at the same time, to solve some ecological problems. The main problem arising with this method is that it needs a large consumption of primary energy carrier - natural gas. The aim of the present work is to study the process with the exergy method and find new effective methods and technological schemes to reduce energy consumption. It is suggested to decompose phosphogypsum using the products from the incomplete combustion of the natural gas with oxygen enriched air and using a preliminarily prepared reducing gas mixture.

  12. Decoupling of sulfur and nitrogen cycling due to biotic processes in a tropical rainforest

    OpenAIRE

    Yi-Balan, Simona A.; Amundson, Ronald; Buss, Heather L

    2014-01-01

    We examined the terrestrial sulfur (S) cycle in the wet tropical Luquillo Experimental Forest (LEF), Puerto Rico. In two previously instrumented watersheds (Icacos and Bisley), chemical and isotopic measurements of carbon (C), nitrogen (N) and S were used to explore the inputs, in-soil processing, and losses of S through comparison to the N cycle. Additionally, the impact of soil forming factors (particularly climate, organisms, topography and parent material) on S cycling in this system was ...

  13. Efficiency of the sulfur-iodine thermochemical water splitting process for hydrogen production based on ADS

    International Nuclear Information System (INIS)

    The current hydrogel production is based on fossil fuels; they have a huge contribution to the atmosphere's pollution. thermochemical water splitting cycles don't present this issue because the required process heat is obtained from nuclear energy and therefore, the environmental impact is smaller than using conventional fuels. One of the promising approaches to produce large quantities of hydrogen in an efficient way using nuclear energy is the sulfur-iodine (S-I) thermochemical water splitting cycle. The nuclear source proposed in this paper is a pebble bed gas cooled transmutation facility. Pebble bed very high temperature advanced systems have great perspectives to assume the future nuclear energy. Software based on Chemical Process Simulation (CPS) can be used to simulate the thermochemical water splitting sulfur-iodine cycle for hydrogen production. In this paper, a model for analyzing the sulfur-iodine process sensibility is developed. Efficiency is also calculated and the influence of different parameters on this value. The behavior of the proposed model before different values of initial reactant's flow is analyzed. (Author)

  14. Conceptual process synthesis for recovery of natural products from plants

    DEFF Research Database (Denmark)

    Malwade, Chandrakant R.; Qu, Haiyan; Rong, Ben-Guang;

    2013-01-01

    A systematic method of conceptual process synthesis for recovery of natural products from their biological sources is presented. This methodology divides the task into two major subtasks namely, isolation of target compound from a chemically complex solid matrix of biological source (crude extrac...... artemisinin obtained in individual unit operations of maceration, flash column chromatography, and crystallization are 90.0%, 87.1, and 47.6%, respectively. Results showed that the crystallization step is dominant to the overall yield of the process which was 37.3%.......A systematic method of conceptual process synthesis for recovery of natural products from their biological sources is presented. This methodology divides the task into two major subtasks namely, isolation of target compound from a chemically complex solid matrix of biological source (crude extract...

  15. Environmental quality and energy conservation in coal conversion processes. [Overall minimization of energy required for sulfur pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, G.L.; Hill, A.H.; Fleming, D.K.

    1979-01-01

    In general, controlling emissions from a coal conversion process is an energy consuming process. In this paper, a parametric assessment of energy requirements for sulfur management in a coal gasification process to produce substitute natural gas is presented. The results of this assessment suggest that the least energy intensive sulfur management practice to utilize in coal gasification plants using low sulfur coal (< 3.5%) is an H/sub 2/S selective removal process providing a Claus plant feed-stream containing 10% or less H/sub 2/S with tail gas from the Claus plant being incinerated in the coal-fired boiler and the additional SO/sub 2/ removed in the flue gas desulfurization (FGD) system. For high sulfur coals (> 3.5%), energy consumptions for all combinations were similar for a given FGD SO/sub 2/ removal specification. As the SO/sub 2/ specification increases for the FGD system, the total energy required for sulfur management also increases. Finally, contrary to expectations, the total energy requirements for sulfur management decrease with increasing sulfur content of the feed coal indicating that the energy requiements of the H/sub 2/S removal process dominates. The total energy requirements for the two Claus plant tail gas treatment processes are similar. Incineration in the boiler is slightly more energy efficient. For low sulfur coals (< 3.5%) the total energy requirements decreased rapidly as the level of H/sub 2/S selective acid-gas removal process decreased from 30% to 10%. For high sulfur coals (> 3.5%) the total energy requirements were similar for all levels of H/sub 2/S in the Claus plant feed gas with a possible minimum in energy requirements for the 15% H/sub 2/S cases.

  16. Uranium extraction process in a sulfuric medium by means of liquid emulsified membranes

    International Nuclear Information System (INIS)

    Uranium ore processing, after leaching by sulfuric acid, by liquid-liquid extraction is a rather heavy process, not suitable for small deposits. Extraction by emulsions was suggested. In this process the leachate is contacted with an oil in water type emulsion, a liquid organic membrane is formed by the continuous phase. Uranium complexes diffuse through the liquid membrane towards the dispersed aqueous phase of the emulsion (stripping solution). Uranium is recovered by breaking the emulsion. Are successively studied: development of stable emulsions, influence of emulsion composition on uranium transfer kinetics, transfer mechanisms through the membrane and modelling of kinetics data obtained in the experimental study

  17. Influence of Sulfur Species on Current Efficiency in the Aluminum Smelting Process

    Science.gov (United States)

    Meirbekova, Rauan; Haarberg, Geir Martin; Thonstad, Jomar; Saevarsdottir, Gudrun

    2016-04-01

    Anode impurities are the major source of sulfur in aluminum electrolysis. Sulfur in anodes is mainly found as organic compounds. Alumina also introduces small quantities of sulfur, typically in the form of sulfates. The scarcity and cost of low-sulfur raw materials and the possibility of sulfur removal from the cell by means of flue gas may make high-sulfur content anodes a viable option. However, some anode impurities are known to affect current efficiency in aluminum production and caution must be exercised. The effect of increased sulfur content in the aluminum electrolysis electrolyte must be studied. This paper explores the effect of increased sulfur concentration in the electrolyte on current efficiency in a laboratory cell. Sodium sulfate was added to the electrolyte as a source of sulfur at regular time intervals to maintain a constant sulfur concentration. Current efficiency decreased by 1.1 pct per each 100 mg/kg (ppm) increase in sulfur concentration in the electrolyte.

  18. Vanadium recovery from oil fly ash by leaching, precipitation and solvent extraction processes

    International Nuclear Information System (INIS)

    In order to reduce the environmental impact due to land disposal of oil fly ash from power plants and to valorize this waste material, the removal of vanadium was investigated using leaching processes (acidic and alkaline treatments), followed by a second step of metal recovery from leachates involving either solvent extraction or selective precipitation. Despite a lower leaching efficiency (compared to sulfuric acid), sodium hydroxide was selected for vanadium leaching since it is more selective for vanadium (versus other transition metals). Precipitation was preferred to solvent extraction for the second step in the treatment since: (a) it is more selective; enabling complete recovery of vanadate from the leachate in the form of pure ammonium vanadate; and (b) stripping of the loaded organic phase (in the solvent extraction process) was not efficient. Precipitation was performed in a two-step procedure: (a) aluminum was first precipitated at pH 8; (b) then ammonium chloride was added at pH 5 to bring about vanadium precipitation

  19. Diamond Processing by Focused Ion Beam - Surface Damage and Recovery

    CERN Document Server

    Bayn, Igal; Cytermann, Catherine; Meyler, Boris; Richter, Vladimir; Salzman, Joseph; Kalish, Rafi

    2011-01-01

    The Nitrogen Vacancy color center (NV-) in diamond is of great interest for novel photonic applications. Diamond nano-photonic structures are often implemented using Focused-Ion-Beam (FIB) processing, leaving a damaged surface which has a detrimental effect on the color center luminescence. The FIB processing effect on single crystal diamond surfaces and their photonic properties is studied by Time of Flight Secondary Ion Mass Spectrometry (TOF-SIMS) and photoluminescence (PL). Exposing the processed surface to hydrogen plasma, followed by chemical etching, drastically decreases implanted Ga concentration, resulting in a recovery of the NV- photo-emission and in a significant increase of the NV-/NV0 ratio.

  20. Supporting technology for enhanced oil recovery - EOR thermal processes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    This report contains the results of efforts under the six tasks of the Eighth Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section.

  1. Phosphorus recovery from sewage sludge by an electrokinetic process

    OpenAIRE

    Ribeiro, A. B.; Couto, N.; Mateus, E.P.; Guedes, P; Ottosen, Lisbeth M.

    2012-01-01

    As population keeps growing, it becomes important to guarantee the supply of staple foods, being necessary to assure good level of nutrients in the soil. Phosphorus (P) is a macronutrient indispensable for plants growth and a non-renewable resource, as phosphorites are estimated to be able to supply P for the next ca. 80 years. Additionally, the quality of this raw material has deteriorated due to contamination, which has increased processing costs of mineral P fertilizers. The recovery of nu...

  2. A Fractional Order Recovery SIR Model from a Stochastic Process.

    Science.gov (United States)

    Angstmann, C N; Henry, B I; McGann, A V

    2016-03-01

    Over the past several decades, there has been a proliferation of epidemiological models with ordinary derivatives replaced by fractional derivatives in an ad hoc manner. These models may be mathematically interesting, but their relevance is uncertain. Here we develop an SIR model for an epidemic, including vital dynamics, from an underlying stochastic process. We show how fractional differential operators arise naturally in these models whenever the recovery time from the disease is power-law distributed. This can provide a model for a chronic disease process where individuals who are infected for a long time are unlikely to recover. The fractional order recovery model is shown to be consistent with the Kermack-McKendrick age-structured SIR model, and it reduces to the Hethcote-Tudor integral equation SIR model. The derivation from a stochastic process is extended to discrete time, providing a stable numerical method for solving the model equations. We have carried out simulations of the fractional order recovery model showing convergence to equilibrium states. The number of infecteds in the endemic equilibrium state increases as the fractional order of the derivative tends to zero. PMID:26940822

  3. Development of measures to improve technologies of energy recovery from gaseous wastes of oil shale processing

    Science.gov (United States)

    Tugov, A. N.; Ots, A.; Siirde, A.; Sidorkin, V. T.; Ryabov, G. A.

    2016-06-01

    Prospects of the use of oil shale are associated with its thermal processing for the production of liquid fuel, shale oil. Gaseous by-products, such as low-calorie generator gas with a calorific value up to 4.3MJ/m3 or semicoke gas with a calorific value up to 56.57 MJ/m3, are generated depending on the oil shale processing method. The main methods of energy recovery from these gases are either their cofiring with oil shale in power boilers or firing only under gaseous conditions in reconstructed or specially designed for this fuel boilers. The possible use of gaseous products of oil shale processing in gas-turbine or gas-piston units is also considered. Experiments on the cofiring of oil shale gas and its gaseous processing products have been carried out on boilers BKZ-75-39FSl in Kohtla-Järve and on the boiler TP-101 of the Estonian power plant. The test results have shown that, in the case of cofiring, the concentration of sulfur oxides in exhaust gases does not exceed the level of existing values in the case of oil shale firing. The low-temperature corrosion rate does not change as compared to the firing of only oil shale, and, therefore, operation conditions of boiler back-end surfaces do not worsen. When implementing measures to reduce the generation of NO x , especially of flue gas recirculation, it has been possible to reduce the emissions of nitrogen oxides in the whole boiler. The operation experience of the reconstructed boilers BKZ-75-39FSl after their transfer to the firing of only gaseous products of oil shale processing is summarized. Concentrations of nitrogen and sulfur oxides in the combustion products of semicoke and generator gases are measured. Technical solutions that made it possible to minimize the damage to air heater pipes associated with the low-temperature sulfur corrosion are proposed and implemented. The technological measures for burners of new boilers that made it possible to burn gaseous products of oil shale processing with low

  4. A microencapsulation process of liquid mercury by sulfur polymer stabilization/solidification technology. Part II: Durability of materials

    OpenAIRE

    López-Delgado, A.; Guerrero, A; López, F. A.; Pérez, C.; Alguacil, F. J.

    2012-01-01

    Under the European LIFE Program a microencapsulation process was developed for liquid mercury using Sulfur Polymer Stabilization/Solidification (SPSS) technology, obtaining a stable concrete-like sulfur matrix that allows the immobilization of mercury for long-term storage. The process description and characterization of the materials obtained were detailed in Part I. The present document, Part II, reports the results of different tests carried out to determine the durability of Hg-S concrete...

  5. Site blocking and CO/sulfur site exchange processes on stepped Pt surfaces

    International Nuclear Information System (INIS)

    The influence of preadsorbed sulfur on the adsorption of CO on Pt(355) and Pt(322) is investigated systematically for sulfur precoverages between 0.02 and 0.30 ML by in situ x-ray photoelectron spectroscopy of the C 1s and S 2p core levels. The two surfaces have the same nominal terrace width of 5 atomic rows, but different step orientation. For both, at low temperatures (130 and 150 K), S preferentially adsorbs at the steps and passivates them for CO adsorption. The required S precoverage is significantly smaller for Pt(322), because of the lower number of steps as a result of the S-induced double-step formation. Upon heating, population of step sites with CO occurs due to irreversible CO/S site exchange. At low S precoverages, the characteristic transition temperatures of 165 K for Pt(355) and 245 K for Pt(322) are significantly different, indicating a higher activation barrier for the CO/S site exchange process for Pt(322). For medium to high S precoverages the transition temperature stays unchanged for Pt(322) but increases for Pt(355). The observed behavior is attributed to a kinetic passivation of the steps by sulfur at low temperatures, which is lifted upon heating.

  6. Simultaneous bioreduction of nitrate and chromate using sulfur-based mixotrophic denitrification process

    Energy Technology Data Exchange (ETDEWEB)

    Sahinkaya, Erkan, E-mail: erkansahinkaya@yahoo.com [Istanbul Medeniyet University, Bioengineering Department, Goztepe, Istanbul (Turkey); Kilic, Adem [Harran University, Environmental Engineering Department, Osmanbey Campus, 63000 Sanliurfa (Turkey); Calimlioglu, Beste; Toker, Yasemin [Istanbul Medeniyet University, Bioengineering Department, Goztepe, Istanbul (Turkey)

    2013-11-15

    Highlights: • Simultaneous heterotrophic and autotrophic denitrification was stimulated. • Simultaneous bioreduction of nitrate and chromate was achieved. • Total chromium decreased <50 μg/L when the influent Cr(VI) was ≤5 mg/L. -- Abstract: This study aims at evaluating simultaneous chromate and nitrate reduction using sulfur-based mixotrophic denitrification process in a column reactor packed with elemental sulfur and activated carbon. The reactor was supplemented with methanol at C/N ratio of 1.33 or 2. Almost complete denitrification was achieved at influent NO{sub 3}{sup −}–N and Cr(VI) concentrations of 75 mg/L and 10 mg/L, respectively, and 3.7 h HRT. Maximum denitrification rate was 0.5 g NO{sub 3}{sup −}–N/(L.d) when the bioreactor was fed with 75 mg/L NO{sub 3}{sup −}–N, 150 mg/L methanol and 10 mg/L Cr(VI). The share of autotrophic denitrification was between 12% and 50% depending on HRT, C/N ratio and Cr(VI) concentration. Effluent total chromium was below 50 μg/L provided that influent Cr(VI) concentration was equal or below 5 mg/L. DGGE results showed stable microbial community throughout the operation and the presence of sulfur oxidizing denitrifying bacteria (Thiobacillus denitrificans) and Cr(VI) reducing bacteria (Exiguobacterium spp.) in the column bed.

  7. Actinides recovery by solvent extraction in NEXT process

    International Nuclear Information System (INIS)

    Concerning the advanced aqueous reprocessing system named NEXT process, the behavior of actinide elements was investigated in main two extraction processes of NEXT process, i.e. the simplified PUREX process for U, Pu and Np recovery, and SETFICS process for Am and Cm recovery. For optimizing the simplified PUREX flowsheet, counter current experiments with centrifugal contactors were carried out under the condition with high HNO3 concentration in the feed solution or scrubbing solution. These experimental results showed the large contribution of HNO3 concentration at the extraction section to Np oxidation and extraction, and the effectiveness of high HNO3 concentration in the feed solution, which might bring the acceleration of the Np oxidation in the feed solution as well as at the extraction section in the centrifugal contactors. In the SETFICS process of a high-loading flowsheet, Am and Cm could be recovered as An(III) product solution. Although Cs was decontaminated well, the decontamination factor of Nd was less than that in the past experiment. (author)

  8. Conversion of cellulosic feedstocks to ethanol and other chemicals using TVA's dilute sulfuric acid hydrolysis process

    International Nuclear Information System (INIS)

    The Tennessee Valley Authority (TVA) has been involved in the conversion of cellulosic feedstocks to ethanol and other products for over 10 years. Laboratory- and bench-scale research has been conducted to develop a two-stage, dilute sulfuric acid hydrolysis process. The process, based on work previously conducted at the Forest Products Laboratory, Madison, Wisconsin, uses high temperatures and pressures and short retention times to convert the hemicellulose and cellulose in biomass to fermentable sugars. Using hardwoods as the primary feedstock, evaluations of the process have resulted in sugar yields equivalent to 60 gallons of ethanol per ton of feedstock. Based on the results of bench-scale work, a two-ton-per-day pilot plant has been constructed and operated to further develop the process. Hydrolysis yields from the pilot-scale facility have been comparable to those achieved in the laboratory. Preliminary estimates have been prepared to determine capital and production costs for a 10-million-gallon-per-year ethanol-from-hardwoods facility. The effect of coproducts such as furfural, acetic acid, and carbon dioxide on production costs was also examined. This paper presents the results of bench- and pilot-scale research along with preliminary economics of TVA's dilute sulfuric acid hydrolysis process

  9. Phosphorus recovery from sewage sludge ash through an electrodialytic process.

    Science.gov (United States)

    Guedes, Paula; Couto, Nazaré; Ottosen, Lisbeth M; Ribeiro, Alexandra B

    2014-05-01

    The electrodialytic separation process (ED) was applied to sewage sludge ash (SSA) aiming at phosphorus (P) recovery. As the SSA may have high heavy metals contents, their removal was also assessed. Two SSA were sampled, one immediately after incineration (SA) and the other from an open deposit (SB). Both samples were ED treated as stirred suspensions in sulphuric acid for 3, 7 and 14 days. After 14 days, phosphorus was mainly mobilized towards the anode end (approx. 60% in the SA and 70% in the SB), whereas heavy metals mainly electromigrated towards the cathode end. The anolyte presented a composition of 98% of P, mainly as orthophosphate, and 2% of heavy metals. The highest heavy metal removal was achieved for Cu (ca. 80%) and the lowest for Pb and Fe (between 4% and 6%). The ED showed to be a viable method for phosphorus recovery from SSA, as it promotes the separation of P from the heavy metals. PMID:24656469

  10. A bench scale hydrogen production test by the thermochemical water-splitting iodine-sulfur process

    International Nuclear Information System (INIS)

    The iodine-sulfur process which utilize nuclear energy has attracted a great deal of interest for economy, environmental conservation and massive production. The IS process should have unique features whereby all chemicals except hydrogen and oxygen circulate through the process. This enables continuous and closed-cycle operations. In order to achieve the operation, process control methods and its automation to maintain the process in a stable state are indispensable. A fundamental concept of the methods was developed, which was installed with automatization in a bench scaled experimental facility made of glass. To demonstrate usefulness of the method, a long-term hydrogen production test was performed. In consequence, stable hydrogen production for 1 weak was successfully accomplished. The production rate of hydrogen was 31NL/h, and the production ratio of oxygen to hydrogen agrees to 0.5:1. This result shows that the water splitting took place stably by effective performance of the control method. (author)

  11. Correlation of capacity fading processes and electrochemical impedance spectra in lithium/sulfur cells

    Science.gov (United States)

    Risse, Sebastian; Cañas, Natalia A.; Wagner, Norbert; Härk, Eneli; Ballauff, Matthias; Friedrich, K. Andreas

    2016-08-01

    The capacity fading of lithium/sulfur (Li/S) cells is one major challenge that has to be overcome for a successful commercialization of this electrochemical storage system. Therefore it is essential to detect the major fading mechanisms for further improvements of this system. In this work, the processes leading to fading are analyzed in terms of a linear four state model and correlated to the distribution of relaxation times calculated with a modified Levenberg-Marquardt algorithm. Additionally, the Warburg impedance and the solution resistance are also obtained by the same algorithm. The detailed analysis of intermediate states during the first cycle gives the distinction between relaxation processes at the sulfur cathode and at the lithium anode. The influence of the polysulfides on the impedance parameters was evaluated using symmetric cells; this yields a good correlation with the results obtained from the first discharge/charge experiment. A fast and a slow capacity fading process are observed for the charge and the discharge during 50 cycles. The fast fading process can be assigned to Faradaic reactions at the lithium anode.

  12. Sulfuric acid on Europa and the radiolytic sulfur cycle

    Science.gov (United States)

    Carlson, R. W.; Johnson, R. E.; Anderson, M. S.

    1999-01-01

    A comparison of laboratory spectra with Galileo data indicates that hydrated sulfuric acid is present and is a major component of Europa's surface. In addition, this moon's visually dark surface material, which spatially correlates with the sulfuric acid concentration, is identified as radiolytically altered sulfur polymers. Radiolysis of the surface by magnetospheric plasma bombardment continuously cycles sulfur between three forms: sulfuric acid, sulfur dioxide, and sulfur polymers, with sulfuric acid being about 50 times as abundant as the other forms. Enhanced sulfuric acid concentrations are found in Europa's geologically young terrains, suggesting that low-temperature, liquid sulfuric acid may influence geological processes.

  13. Cogeneration and Heat Recovery in the Industrial Process

    Directory of Open Access Journals (Sweden)

    Vujasinović, E.

    2007-11-01

    Full Text Available Related to energy requirements for non-cellulose i. e. polyester production as an energy-intensive process, potential saving options are proposed. From the process data, it is evident that unit operations need electric and thermal energy in significant amounts. At the same time, improved energy management could be realized by applying a combined heat and power system (CHP instead of the usually used process with separate heat and power production. In addition, the boiler flue gases with a sufficiently high outlet temperature could be used for combustion air preheating.Considering industrial process data, a calculation and comparison between the primary energy demand for conventional, CHP system and flue-gas heat recovery is presented. Comparison between separate heat and electricity production i.e. the conventional system with an overall efficiency of 55.6 % and CHP with efficiency of 85 %, shows an absolute efficiency increase of 29.4 %. Using an air preheater for combustion air temperature increasing saves 5.6 % of the fuel and at the same time diminishes thermal pollution because the exhaust flue-gas temperature becomes 77.3 °C instead of 204 °C. Conclusively, cogeneration and flue-gas heat recovery presentsfuel savings, which also implies economic and environmental benefits.

  14. An efficient hybrid sulfur process using PEM electrolysis with a bayonet decomposition reactor - HTR2008-58207

    International Nuclear Information System (INIS)

    The Hybrid Sulfur (HyS) Process is being developed to produce hydrogen by water-splitting using heat from advanced nuclear reactors. It has the potential for high efficiency and competitive hydrogen production cost, and has been demonstrated at a laboratory scale. As a two-step process, the HyS is one of the simplest thermochemical cycles. The sulfuric acid decomposition reaction is common to all sulfur cycles, including the Sulfur-Iodine (SI) cycle. What distinguishes the HyS Process from the other sulfur cycles is the use of sulfur dioxide (SO2) to depolarize the anode of a water electrolyzer. The two critical HyS Process components are the SO2- depolarized electrolyzer (SDE), and the high-temperature decomposition reactor. A proton exchange membrane (PEM)- type SDE and a silicon carbide bayonet-type high-temperature decomposition reactor are being developed for DOE's Nuclear Hydrogen Initiative (NHI) by Savannah River National Laboratory (SRNL) and by Sandia National Laboratories (SNL), respectively. The ultimate goal of the NHI-sponsored work is to couple the SDE and the reactor in an integrated laboratory scale experiment to prove the technical readiness of the HyS cycle for the NGNP demonstration. This paper describes the flowsheet that is being prepared to combine these two components into a viable process and presents the latest performance projections and economics for a HyS Process coupled to a PBMR heat source. The basic flowsheet for this process has been described elsewhere [4]. It requires an acid concentration section because the SDE product, which is limited to no more than 50% H2SO4 by cell voltage considerations, is too dilute to be fed directly to the bayonet, which needs at least 65% H2SO4 in the feed for acceptable performance. Optimization involved trade-offs between decomposition reaction and acid concentration heat requirements. The PBMR heat source can split its heat output between the decomposition reaction and either steam (which could be

  15. Global warming potential of the sulfur-iodine process using life cycle assessment methodology

    International Nuclear Information System (INIS)

    A life cycle assessment (LCA) of one proposed method of hydrogen production - thermochemical water-splitting using the sulfur-iodine cycle couple with a very high-temperature nuclear reactor - is presented in this paper. Thermochemical water-splitting theoretically offers a higher overall efficiency than high-temperature electrolysis of water because heat from the nuclear reactor is provided directly to the hydrogen generation process, instead of using the intermediate step of generating electricity. The primary heat source for the S-I cycle is an advanced nuclear reactor operating at temperatures corresponding to those required by the sulfur-iodine process. This LCA examines the environmental impact of the combined advanced nuclear and hydrogen generation plants and focuses on quantifying the emissions of carbon dioxide per kilogram of hydrogen produced. The results are presented in terms of global warming potential (GWP). The GWP of the system is 2500 g carbon dioxide-equivalent (CO2-eq) per kilogram of hydrogen produced. The GWP of this process is approximately one-sixth of that for hydrogen production by steam reforming of natural gas, and is comparable to producing hydrogen from wind- or hydro-electric conventional electrolysis. (author)

  16. Accidents with sulfuric acid

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2006-01-01

    Full Text Available Sulfuric acid is an important industrial and strategic raw material, the production of which is developing on all continents, in many factories in the world and with an annual production of over 160 million tons. On the other hand, the production, transport and usage are very dangerous and demand measures of precaution because the consequences could be catastrophic, and not only at the local level where the accident would happen. Accidents that have been publicly recorded during the last eighteen years (from 1988 till the beginning of 2006 are analyzed in this paper. It is very alarming data that, according to all the recorded accidents, over 1.6 million tons of sulfuric acid were exuded. Although water transport is the safest (only 16.38% of the total amount of accidents in that way 98.88% of the total amount of sulfuric acid was exuded into the environment. Human factor was the common factor in all the accidents, whether there was enough control of the production process, of reservoirs or transportation tanks or the transport was done by inadequate (old tanks, or the accidents arose from human factor (inadequate speed, lock of caution etc. The fact is that huge energy, sacrifice and courage were involved in the recovery from accidents where rescue teams and fire brigades showed great courage to prevent real environmental catastrophes and very often they lost their lives during the events. So, the phrase that sulfuric acid is a real "environmental bomb" has become clearer.

  17. Phosphorus recovery from sewage sludge by an electrokinetic process

    DEFF Research Database (Denmark)

    Ribeiro, A.B.; Couto, N.; Mateus, E.P.;

    waste water treatment plants (WWTP) may contain contaminants or unwanted elements regarding specific applications, but they also contain secondary resources of high value. Using these ash as a P resource, while removing the contaminants, seems a sustainable option. The electrokinetic (EK) process can be...... phosphate will selectively accumulate in the anolyte allowing its recovery. EK remediation is being applied at a laboratory scale, in different matrices and the set of major parameters, which affect the efficiency of EK (e.g. current density, potential difference between electrodes) are being tested and...

  18. Bidentate organophosphorus solvent extraction process for actinide recovery and partition

    Science.gov (United States)

    Schulz, Wallace W.

    1976-01-01

    A liquid-liquid extraction process for the recovery and partitioning of actinide values from acidic nuclear waste aqueous solutions, the actinide values including trivalent, tetravalent and hexavalent oxidation states is provided and includes the steps of contacting the aqueous solution with a bidentate organophosphorous extractant to extract essentially all of the actinide values into the organic phase. Thereafter the respective actinide fractions are selectively partitioned into separate aqueous solutions by contact with dilute nitric or nitric-hydrofluoric acid solutions. The hexavalent uranium is finally removed from the organic phase by contact with a dilute sodium carbonate solution.

  19. Process Optimization for Valuable Metal Recovery from Dental Amalgam Residues

    Directory of Open Access Journals (Sweden)

    C.M. Parra–Mesa

    2009-07-01

    Full Text Available In this paper, the methodology used for optimizing leaching in a semi pilot plant is presented. This leaching process was applied to recover value metals from dental amalgam residues. 23 factorial design was used to characterize the process during the first stage and in the second one, a central compound rotational design was used for modeling copper percentage dissolved, a function of the nitric acid concentration, leaching time and temperature. This model explained the 81% of the response variability, which is considered satisfactory given the complexity of the process kinetics and, furthermore, it allowed the definition of the operation conditions for better copper recovery, which this was of 99.15%, at a temperature of 55°C, a concentration of 30% by weight and a time of 26 hours.

  20. Improved oil recovery process for heavy oil: a review

    Energy Technology Data Exchange (ETDEWEB)

    Barillas, J.L.M.; Dutra Junior, T.V.; Mata, W. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Engenharia Quimica], E-mail: jennys@eq.ufrn.br

    2008-01-15

    Petroleum is one of the main sources of energy in the world, occupying the first place of the Brazilian energy matrix. Therefore, technologies that involve the development and application of techniques capable of increasing the profitability of oil fields are important and require more thorough studies. In Brazil, self-sufficiency has been already reached in oil production, however it is necessary that improved oil recovery technologies be continually studied to maintain the current production or to increase it. Rio Grande do Norte (a Brazilian State) comprises many heavy oil reserves and the exploration activities in the Brazilian Basins of Campos, Santos and Espirito Santo have led to the discovery of large amounts of heavy oils. It is possible to increase heavy oil recovery in some of these reservoirs with the help of improved oil recovery processes, thus enhancing oil field productivity and profitability. Until recently, heavy oil reserves did not attract much interest. The lowest oil profitability, the low price of the oil barrel in the international market, the difficulties involved in its extraction and its refining, and the large amount of light and medium oils to be explored could not justify the investments. Maturity of light and medium oil fields and the significant increase in oil price placed that source of energy under a new perspective. In Brazil, the confirmed reserves constitute 2.9 billion barrels approximately, 26% of the total reserves, and the production should reach 450 thousand barrels daily or 25% of the total production predicted for 2010 (ANP, 'Agencia Nacional do Petroleo' - Brazilian Petroleum National Agency, 2006). To improve the capacity of drainage of the heavy oils and to increase its recovery, different thermal methods have been developed. Those more used involve steam in the process, because they are more efficient than other processes such as 'in situ' combustion or water injection. The steam is used with the

  1. Study and make sulfur dioxide treatment equipment for degradation process of fine silicate zircon ore by sulfuric acid

    International Nuclear Information System (INIS)

    The against absorbent method was researched by research group to solve the above issue. This method was carried out by adsorbent lime-milk agent on the buffer of porous material with diameter D=9 cm and height H=1.2 m. The main parameters were gained: absorbent effect reached 98% with lime-milk concentration of 14% in water, against air flow speed of 0.7 m/s and lime-milk output of 0.45 liter/minute. Base on the above main researched parameter, the SO2 treatment equipment system by sulfuric acid was worked out with the scale of 0.5 ton/batch/day; absorbent tower diameter D=0.47 m, buffer height H=3.5 m and expenditure of 33.2 kg CaO/ton of zircon silicate. (author)

  2. Phosphorus recovery from sewage sludge by an electrokinetic process

    DEFF Research Database (Denmark)

    Ribeiro, A.B.; Couto, N.; Mateus, E.P.;

    ash (SSA) may contain contaminants or unwanted elements regarding specific applications, but they also contain secondary resources of high value (e.g. elements with fertilizer value). The incineration of SS is an highly used technique, namely in the Northern part of Europe. With SS incineration, the...... matrix volume will be significantly reduced and, at the same time, organic contaminants (such as PCB, PAH, …) will be thermally destructed. However, heavy metals still remain in the ashes and, to “re-use” them as fertilizer, inorganic contaminants should be removed. Electrokinetic transport process (EK...... supply P for the next ca. 80 years. Additionally, the quality of this raw material has deteriorated due to contamination, which has increased processing costs of mineral P fertilizers. The recovery of nutrients, like P, from secondary resources urges. Waste streams as sewage sludge (SS) and sewage sludge...

  3. Screening of microorganisms for microbial enhanced oil recovery processes

    Energy Technology Data Exchange (ETDEWEB)

    Yonebayashi, H. [Japan National Oil Corp., Tokyo (Japan); Yoshida, S. [Japan Food Research Laboratiories, Tokyo (Japan). Div. of Microbiology; Ono, K. [Japan National Oil Corp., Chiba (Japan). Tech. Research Center; Enomoto, H. [Tohoku University, Sendai (Japan). Dept. of Geoscience and Tech.

    2000-01-01

    The objective of this study is to screen effective microorganisms for the Microbial Enhanced Oil Recovery process (or simply as MEOR). Samples of drilling cuttings, formation water, and soil were collected from domestic drilling sites and oil fields. Moreover, samples of activated-sludge and compost were collected from domestic sewage treatment facility and food treatment facility. At first, microorganisms in samples were investigated by incubation with different media; then they were isolated. By two stage-screening based on metabolizing ability, 4 strains (Bacillus licheniformis TRC-18-2-a, Enterobacter cloacae TRC-322, Bacillus subtilis TRC-4118, and Bacillus subtilis TRC-4126) were isolated as effective microorganisms for oil recovery. B. licheniformis TRC-18-2-a is a multifunctional microorganism possessing excellent surfactant productivity, and in addition it has gas, acid and polymer productivities. E. cloacae TRC-332 has gas and acid producing abilities. B. subtilis TRC-4118 and TRC-4126 are effective biosurfactant producers, and they reduce the interfacial tension to 0.04 and 0.12 dyne/cm, respectively. (author)

  4. Structural development and dynamic process in sulfurizing precursors to prepare Cu2ZnSnS4 absorber layer

    International Nuclear Information System (INIS)

    Highlights: • CZTS films were fabricated by sulfurizing the fabricated precursor films. • Annealing time and temperature are very important for synthesis of pure CZTS films. • Pure CZTS films with high quality can prepared at 500 °C and 90 min. • Both high temperature and long heating time causes the decomposition of CZTS films. -- Abstract: Cu2ZnSnS4 (CZTS) films were fabricated by sulfurizing the fabricated metal-precursor films under sulfur atmosphere. All samples prepared at different conditions were characterized by X-ray diffraction, Raman scattering measurements, scanning electron microscopy, energy dispersive X-ray spectroscopy, and UV spectrophotometer. We systematically studied the influence of sulfurization time and temperature on structures, morphologies, compositions, and optical properties, and analyzed deeply the transformation of structural phase and dynamic process during the formation process of CZTS films. Experimental results indicate that the proper sulfurization time and temperature play an important role in synthesizing pure CZTS films with high quality. Compared with the others, the prepared sample at 500 °C and 90 min shows uniform surface morphology, excellent crystal quality, and optical properties. Various growth conditions realize the modulation of structure, impurity phase, morphology and optical properties. The present research results are helpful for us to deeply understand the growth process of CZTS film and pave the way for realizing the fabrication of high quality CZTS absorption layer

  5. Characterization of phenolic constituents inhibiting the formation of sulfur-containing volatiles produced during garlic processing.

    Science.gov (United States)

    Li, Wen-Qing; Zhou, Hua; Zhou, Mei-Yun; Hu, Xing-Peng; Ou, Shi-Yi; Yan, Ri-An; Liao, Xiao-Jian; Huang, Xue-Song; Fu, Liang

    2015-01-28

    Garlic (Allium sativum L.), which is a widely distributed plant, is globally used as both spice and food. This study identified five novel phenolic compounds, namely, 8-(3-methyl-(E)-1-butenyl)diosmetin, 8-(3-methyl-(E)-1-butenyl)chrysin, 6-(3-methyl-(E)-1-butenyl)chrysin, and Alliumones A and B, along with nine known compounds 6-14 from the ethanol extract of garlic. The structures of these five novel phenolic compounds were established via extensive 1D- and 2D-nuclear magnetic resonance spectroscopy experiments. The effects of the phenolic compounds isolated from garlic on the enzymatical or nonenzymatical formation of sulfur-containing compounds produced during garlic processing were examined. Compound 12 significantly reduced the thermal decomposition of alliin, whereas compound 4 exhibited the highest percentage of alliinase inhibition activity (36.6%). PMID:25579175

  6. Electrolytic technique for the chemical decontamination process with sulfuric acid-cerium (IV) for decommissioning

    International Nuclear Information System (INIS)

    An electrolyzer with an ion-exchange membrane as the separator has been used to study the electrolytic redox reaction of Ce4+ / Ce3+ in sulfuric acid solution, which is a reagent for predismantling system decontamination. Influencing factors such as current density, cerium concentration, acidity, electrolyte flow rate, membrane type and electrode material were studied experimentally. The results indicate that the redox can be achieved with high conversion even as the cerium concentration is below 0.005 M. However, the current efficiency strongly depends on the cerium concentration. In addition, the acid content and the electrolyte flow rate show little influence on the redox reaction. Both cation and anion membrane are feasible for this process. Therefore, the operation conditions are widely applicable. Moreover, two different electrode materials, platinized titanium meshes and graphite, were used. The results show that the platinized titanium meshes is preferable to the graphite for higher current efficiency. (author)

  7. Processing methods for producing lead and elemental sulfur of synthetic mixtures

    OpenAIRE

    Golomeov, Blagoj; Krstev, Boris; Krstev, Aleksandar

    2009-01-01

    These investigations have developed an effective hydrometallurgical method to recover high-purity lead metal and elemental sulfur from simulated galena synthetic mixures eliminating sulfur gases and lead emissions, in contrast to the current high-temperature smelting technology. The method consists of different operations: oxidative leaching with production of solution with residue containing elemental sulfur., electrowinning by the solution with metal production. The obtained results d...

  8. New processing methods for producing lead and elemental sulfur from ores

    OpenAIRE

    Golomeov, Blagoj; Krstev, Boris; Golomeova, Mirjana; Krstev, Aleksandar

    2009-01-01

    These investigations have developed an effective hydrometallurgical method to recover high-purity lead metal and elemental sulfur from simulated galena synthetic mixures eliminating sulfur gases and lead emissions, in contrast to the current high-temperature smelting technology. The method consists of different operations: oxidative leaching with production of solution with residue containing elemental sulfur., electrowinning by the solution with metal production. The obta...

  9. Sulfur barrier for use with in situ processes for treating formations

    Science.gov (United States)

    Vinegar, Harold J.; Christensen, Del Scot

    2009-12-15

    Methods for forming a barrier around at least a portion of a treatment area in a subsurface formation are described herein. Sulfur may be introduced into one or more wellbores located inside a perimeter of a treatment area in the formation having a permeability of at least 0.1 darcy. At least some of the sulfur is allowed to move towards portions of the formation cooler than the melting point of sulfur to solidify the sulfur in the formation to form the barrier.

  10. Sulfur behavior in the Sasol-Lurgi fixed-bed dry-bottom gasification process

    Energy Technology Data Exchange (ETDEWEB)

    M. Pat Skhonde; R. Henry Matjie; J. Reginald Bunt; A. Christien Strydom; H. Schobert [Sasol Technology R& amp; D, Sasolburg (South Africa)

    2009-01-15

    This article reports on the findings of a study regarding the sulfur behavior across a Sasol-Lurgi gasifier. This was undertaken to understand the behavior of the various sulfur-bearing components in the coal, as they are exposed to the conditions in the gasifier. In this study, conventional characterization techniques were employed to monitor the behavior of sulfur-bearing mineral matter across the gasifier. It was observed from the study that the sulfur-bearing mineral (pyrite) in the coal structure undergoes various changes with pyrite being transformed to pyrrhotite and then to various oxides of iron with the subsequent loss of sulfur to form H{sub 2}S. A low proportion of the sulfur species including the organically associated sulfur was encapsulated by a melt that was formed by the interaction between kaolinite and fluxing minerals (pyrite, calcite, and dolomite/ankerite) present in the coal at elevated temperatures and pressure, thereby ending up in the ash. The remaining small proportions of sulfur-bearing mineral matter including pyrite and organically bound sulfur in the unburned carbon in the carbonaceous shales also report to the ash. 18 refs., 8 figs., 2 tabs.

  11. 40kt/a硫回收联合装置烧氨实践%Practice of burning ammonia in a 800 b/d sulfur recovery unit

    Institute of Scientific and Technical Information of China (English)

    耿庆光; 李步; 黄占修

    2011-01-01

    The new sulfur recovery unit in SINOPEC Luoyang Company was designed to burn 0.5% 1.5% ammonia in sour gas. Due to the insufficient capacity of ammonia refining unit, 15% of ammonia in sour gas had to be burned for more than one year, thus balancing the ammonia gas produced by the new 11 t/h sour water stripper. The operation shows that the unit is reliable in design and has no plugging. The catalyst activity is normally maintained and sulfur quality and tail gas emission meet the specifications. Good operating experience has been accumulated.%中国石油化工股份有限公司洛阳分公司新建40 kt/a硫回收联合装置原设计酸性气中烧氨比例为0.5%~1.5%,因氨精制系统不匹配,进行了一年多的烧氨,烧氨比例达到15%,平衡了新建11t/h污水汽提装置产生的全部氨气.运行结果表明装置设计可靠,系统无堵塞,催化剂活性正常,硫黄质量正常,尾气排放达标,并积累了一定的生产操作经验.

  12. Analysis and optimal process development of the iodine-Sulfur cycle for nuclear hydrogen production

    International Nuclear Information System (INIS)

    Hydrogen is expected to be a main energy vector for the future society. Among many thermo-chemical water splitting technologies for mass production of hydrogen, Iodine-Sulfur (I-S) cycle is considered to be the most promising one. Originated in the 1980s by General Atomics in the United States, the I-S cycle utilizes high temperature heat from energy sources such as nuclear reactors. Despite its high viability relative to many other options, lots of technical challenges need to be resolved until it can practically contribute to the mass production of hydrogen. In the present work, based on the experimental data available from previous works and discussions collected through the literature survey, the optimal operating conditions were proposed for the Bunsen reaction, considering the key concerns of the I-S cycle: i.e., the liquid-liquid (L-L) phase separation performance, the water distributions between the sulfuric acid and poly-hydroiodic acid (HIx) phases, the side reactions, and the operating cost due to the excess iodine and water. All the available experimental data were combined together, and a series of parametric studies were done to find out any trends among parameters. The optimal operating point is determined as 4 mol of excess iodine and 11 mol of excess water in the stoichiometry at temperature of 330K, while the allowable window ranges between 4∼6 mol for excess iodine, 11∼13 moles for excess water, and 330∼350K for temperature. As for the distribution of excess water after the Bunsen reaction and L-L phase separation, 5 mol moves to the sulfuric acid phase and 6∼8 mol to the HIx phase. By controlling the operation within this window, it should be possible to avoid the side reaction and iodine solidification, to increase the HI concentration well above the azeotrope in the HIx section, and to minimize the operating cost caused by the excess iodine and water. With the optimized Bunsen reaction process to yield an over-azeotropic HI liquid

  13. Linking Food Webs and Biogeochemical Processes in Wetlands: Insights From Sulfur Isotopes

    Science.gov (United States)

    Stricker, C. A.; Guntenspergen, G. R.; Rye, R. O.

    2005-05-01

    To better understand the transfer of nutrients into prairie wetland food webs we have investigated the cycling of S (via S isotope systematics and geochemistry) in a prairie wetland landscape by characterizing sources (ground water, interstitial water, surface water) and processes in a small catchment comprised of four wetlands in eastern South Dakota. We focused on S to derive process information that is not generally available from carbon isotopes alone. The wetlands chosen for study spanned a considerable range in SO4 concentration (0.1-13.6 mM), which corresponded with landscape position. Ground water δ34SSO4 values remained relatively constant (mean = -13.2 per mil) through time. However, δ34SSO4 values of wetland surface waters ranged from -2.9 to -30.0 per mil (CDT) and were negatively correlated with SO4 concentrations (pOdonata: Anax sp.) consumers were significantly related to surface water δ34SSO4 values (p<0.05) suggesting that food web components were responding to changes in the isotopic composition of the S source. Both primary and secondary consumer δ34S signatures differed between wetlands (ANOVA, p<0.05). These data illustrate the complexity of S cycling in prairie wetlands and the influence of wetland hydrologic and biogeochemical processes on prairie wetland food webs. Additionally, this work has demonstrated that sulfur isotopes can provide unique source and process information that cannot be derived from traditional carbon and nitrogen isotope studies.

  14. 硫回收超级克劳斯尾气管段烧红原因分析与处理%Analysis and Treatment on Red-Hot Exhaust Pipe in Super Claus Sulfur Recovery Unit

    Institute of Scientific and Technical Information of China (English)

    郭志强

    2013-01-01

    分析硫回收装置开车阶段入焚烧炉尾气管段烧红的原因,并提出相应的处理措施。%Analyze the causes of red-hot exhaust pipe of the incinerator during operation of the sulfur recovery unit , and propose the appropriate measures .

  15. Sulfur Mustard

    Science.gov (United States)

    ... Matters What's New A - Z Index Facts About Sulfur Mustard What sulfur mustard is Sulfur mustard is a type of ... it is in liquid or solid form. Where sulfur mustard is found and how it is used ...

  16. Sulfide-oxidizing bacteria establishment in an innovative microaerobic reactor with an internal silicone membrane for sulfur recovery from wastewater.

    Science.gov (United States)

    Valdés, F; Camiloti, P R; Rodriguez, R P; Delforno, T P; Carrillo-Reyes, J; Zaiat, M; Jeison, D

    2016-06-01

    A novel bioreactor, employing a silicone membrane for microaeration, was studied for partial sulfide oxidation to elemental sulfur. The objective of this study was to assess the feasibility of using an internal silicone membrane reactor (ISMR) to treat dissolved sulfide and to characterize its microbial community. The ISMR is an effective system to eliminate sulfide produced in anaerobic reactors. Sulfide removal efficiencies reached 96 % in a combined anaerobic/microaerobic reactor and significant sulfate production did not occur. The oxygen transfer was strongly influenced by air pressure and flow. Pyrosequencing analysis indicated various sulfide-oxidizing bacteria (SOB) affiliated to the species Acidithiobacillus thiooxidans, Sulfuricurvum kujiense and Pseudomonas stutzeri attached to the membrane and also indicated similarity between the biomass deposited on the membrane wall and the biomass drawn from the material support, supported the establishment of SOB in an anaerobic sludge under microaerobic conditions. Furthermore, these results showed that the reactor configuration can develop SOB under microaerobic conditions and can improve and reestablish the sulfide conversion to elemental sulfur. PMID:27003697

  17. Recovery of Mo and Co from refinery spent catalysts and selection of optimum recovery process

    International Nuclear Information System (INIS)

    Recovery of precious metals from spent catalysts is justified due to mainly environmental regulations, concerns of sustained development and economic added value. In this work recovery of Molybdenum and Cobalt from spent refinery catalysts are studied. Various methods of recovery of these metals from spent catalysts have been reviewed and compared. Experimental methods have been used to find the practical methods and optimum conditions for recovery. It has been found that one can recover about 93% of the initial Co by solving the catalyst in boiling water and about 97% of the initial Mo by leaching with Na CI and 85% by leaching with Na2CO3, solution in presence of H2O2 of spent Hydrotreating catalyst

  18. Obtention process of phosphorus 32 starting from commercial sulfur and design and construction of the radiochemical separation prototype

    International Nuclear Information System (INIS)

    In this work an obtention process of phosphorus 32 (32 P) in orthophosphoric acid form (H332PO4) is described starting from commercial sulfur. Also the design and construction of the experimental prototype used in the radiochemical separation and their results in three tests carried out is reported. (Author)

  19. Experimental Study on Treatment of High-concentrated Sulfur Wastewater by Process of Depositing Natrojarosite and Its Environmental Significance

    Institute of Scientific and Technical Information of China (English)

    MA Shengfeng; WANG Changqiu; LU Anhuai; GUO Yanjun; HE Hongliao

    2007-01-01

    High-concentrated sulfur wastewater with sodium and COD (chemical oxygen demand) up to 26000 mg/L from a chemical plant, Jiangsu Province of China has been treated by deposition of natrojarosite in lab. The results indicated that the COD of the wastewater was decreased sharply from 26000 mg/L to 1001 mg/L, with removal rate of COD up to 96% by twice precipitations of natrojarosite and twice oxidation of H2O2. The treated sulfur wastewater reached the requirement of subsequent biochemical treatment to water quality. The optimal operational parameters should be controlled on provided an experimental basis for pretreatment of high-concentrated sulfur wastewater and proposed a new mineralogical method on treatment of other wastewaters. Depositing process ofjarosite and its analogs should be able to be used to treat wastewater from mine and other industries to remove S, Fe and other toxic and harmful elements, such as As, Cr, Hg, Pb, etc. in the water.

  20. Neurofunctional Reward Processing Changes in Cocaine Dependence During Recovery.

    Science.gov (United States)

    Balodis, Iris M; Kober, Hedy; Worhunsky, Patrick D; Stevens, Michael C; Pearlson, Godfrey D; Carroll, Kathleen M; Potenza, Marc N

    2016-07-01

    Although reward processing appears altered in addiction, few studies track neurofunctional changes following treatment or relate these to measures of reduced drug use. The current study examined neurofunctional alterations in reward processing in cocaine dependence (CD) pretreatment and posttreatment to determine whether these changes relate to clinically meaningful outcome indicators. Treatment-seeking CD outpatients (N=29) underwent functional magnetic resonance imaging while performing a monetary incentive delay task (MIDT) pretreatment and posttreatment. The MIDT parses anticipatory from outcome phases of reward/loss processing. Abstinence indicators (negative urines, days abstinent from cocaine during follow-up) were collected throughout treatment and up to 1 year later. Healthy control (HC) participants (N=28) were also scanned twice with the MIDT. Relative to pretreatment, at posttreatment CD participants demonstrated increased anticipatory reward activity in the midbrain, thalamus, and precuneus (pFWEcocaine abstinence during the 1-year follow-up. Ventral striatal (VS) activity during loss anticipation correlated negatively with negative urine screens. HC group test-retest results showed decreased ventromedial prefrontal cortex activity during winning outcomes. CD-HC group-by-time differences revealed increased left inferior frontal gyrus activity in the CD group during anticipatory phases at posttreatment. In CD participants, increased posttreatment activity in dopamine-innervated regions suggests lowered thresholds in anticipatory signaling for non-drug rewards. Midbrain and VS responses may represent biomarkers associated with CD abstinence. Abstinence-related neurobiological changes occur in similar regions implicated during active use and may possibly be used to track progress during short- and long-term recovery. PMID:26792441

  1. Processing of spent nickel catalyst for fat recovery

    Directory of Open Access Journals (Sweden)

    Ibrahim Nasir, Mohammad

    2002-06-01

    Full Text Available Spent nickel catalyst (SNC have the potential of insulting the quality of the environment in a number of ways. The disposal of SNC will have a pollution effect. Optimum recovery of fat from SNC , could save the environment and reduce the oil loss. Hexane has been the solvent of choice for oil extraction. Alternative solvents that are considered safer have been evaluated. Hexane, isopropanol, ethanol, and heptane were examined using soxhlet extraction. While hexane was more efficient in oil recovery from SNC, isopropanol proved to be very good, to clarifying separation of oil from waste material and also provide high solvent recovery compared to other solvents. Isopropanol extraction with chill provided separation of miscella into two phases: lower oil–rich and an upper solvent – rich. It saved much energy of vaporization for distilling. An aqueous extraction process with immiscible solvent assisted was tested. Solvent like hexane added to SNC, and water added later with continuous stirring. The mixture was stirred for about 30 minutes, prior to centrifugation. Aqueous process extracted less amount of oil compared to solvent extraction.El catalizador agotado de níquel (SNC tiene el potencial de dañar la calidad del medio ambiente de diversas formas. El depósito de SNC tendrá un efecto de polución. La recuperación óptima de la grasa a partir del SCN, podría conservar el medio ambiente y reducir la pérdida de aceite. El hexano ha sido el disolvente elegido para la extracción del aceite. También se han evaluado disolventes alternativos que son considerados seguros. Se han examinado hexano, isopropanol, etanol y heptano usando extracción con soxhlet. Mientras que el hexano fue el mas eficaz en la recuperación del aceite, el isopropanol demostró ser muy bueno para aclarar la separación del aceite a partir de la materia residual y también proporcionó una alta recuperación del disolvente en comparación con los otros

  2. Supporting technology for enhanced oil recovery for thermal processes

    Energy Technology Data Exchange (ETDEWEB)

    Reid, T.B.; Bolivar, J.

    1997-12-01

    This report contains the results of efforts under the six tasks of the Ninth Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections (for each of the 6 tasks) and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section. The tasks are numbered 62 through 67. The first, second, third, fourth fifth, sixth, seventh, eighth, and ninth reports on Annex IV, [Venezuela MEM/USA-DOE Fossil Energy Report IV-1, IV-2, IV-3, IV-4, IV-5, IV-6, IV-7, and IV-8 (DOE/BETC/SP-83/15, DOE/BC-84/6/SP, DOE/BC-86/2/SP, DOE/BC-87/2/SP, DOE/BC-90/1/SP, DOE/BC-90/1/SP) (DOE/BC-92/1/SP, DOE/BC-93/3/SP, and DOE/BC-95/3/SP)] contain the results from the first 61 tasks. Those reports are dated April 1983, August 1984, March 1986, July 1987, November 1988, October 1991, February 1993, and March 1995 respectively.

  3. USING THE SULFUR POLYMER STABILIZATION SOLIDIFICATION PROCESS TO TREAT RESIDUAL MERCURY WASTES FROM GOLD MINING OPERATIONS.

    Energy Technology Data Exchange (ETDEWEB)

    BOWERMAN,B.ADAMS,J.KALB,P.WAN,R.Y.LEVIER,M.

    2003-02-24

    Large quantities of mercury are generated as a by-product during the processing of gold ore following mining operations. Newmont Mining Corporation (NMC), which operates some of the world's largest gold mines, sought a method to permanently ''retire'' its mercury by-products, thereby avoiding potential environmental liability. Sulfur Polymer Stabilization-Solidification (SPSS) is an innovative technology developed at Brookhaven National Laboratory (BNL) for treatment of mercury and mercury contaminated materials, such as soil, sludge and debris. BNL conducted a treatability study to determine the potential applicability of SPSS for treatment of Newmont mercury, and the treated product passed the U.S. Environmental Protection Agency (EPA) test for toxicity. The SPSS process has been shown to be effective on radioactive and nonradioactive mercury and mercury-contaminated materials with a pilot-scale batch system capable of producing 0.03 m{sup 3} (1 ft{sup 3}) per batch. Engineering scale-up issues are discussed and material property tests addressing these issues are described.

  4. Contributions of organic matter and organic sulfur redox processes to electron flow in anoxic incubations of peat

    Science.gov (United States)

    YU, Zhiguo; Peiffer, Stefan; Göttlicher, Jörg; Knorr, Klaus-Holger

    2015-04-01

    Anaerobic decomposition of peat soils involves a number of interdependent microbial processes that ultimately generate CO2 and CH4. In many peat soils, a high ratio of CO2:CH4 was reported, which presumably results from a direct or indirect role of soil organic matter serving as an electron acceptor. Therefore, in this study we intended to test the hypothesis that organic matter (OM) suppresses methanogenesis and sustains anaerobic CO2 production, serving as i) direct electron acceptor or ii) via supporting internal sulfur cycling to maintains CO2 production through bacterial sulfate reduction (BSR). We incubated peat samples of commercial bog peat, inoculated with a small amount of fresh peat to introduce an active microbial community. Samples were amended with sulfate or sulfide and incubated under anoxic conditions for 6 weeks at 30 ° C. Upon anaerobic incubation of peat virtually devoid of inorganic electron acceptors, CO2 and CH4 were produced at a ratio of 3.2. According to the electron budget, the calculated electron accepting capacity (EAC) of OM was 2.36 μeq cm3 d-1. Addition of sulfate significantly increased CO2 production and effectively suppressed CH4 production. After subtracting the EAC provided though sulfate addition (0.97~2.81 μeq cm-3 d-1), EACs supplied by OM reached 3.88 to 4.85 μeq cm-3 d-1.The contribution of organic sulfur was further evaluated by XANES spectroscopy and using natural abundance of δ34S as a tracer. Results demonstrated that BSR involved both addition of H2S and sulfate to OM leading to a formation of reduced organic sulfur and partial changes of oxidized organic sulfur species. The original peat prior to incubation contained 70.5% reduced organic S (R-S-H, R-S-R, R-S-S-R), and 25.9% oxidized S (R-SO3, R-SO2-R, R-SO4-R), whereas the treatment with H2S or sulfate addition comprised 75.7~ 81.1% reduced organic S, and only 21.1~18.9 % oxidized S. Our results imply that that organic matter contributes to anaerobic respiration

  5. EFFICIENT RECOVERY OF BIOETHANOL USING NOVEL PERVAPORATION-DEPHLEGMATION PROCESS

    Science.gov (United States)

    Bioethanol is the most important liquid fuel made in the U.S. from domestically produced renewable resources. Traditional production of bioethanol involves batch fermation of biomass followed by ethanol recovery from the fermentation broths using distillation. The distillation st...

  6. Wastewater resource recovery via the Enhanced Biological Phosphorus Removal and Recovery (EBP2R) process coupled with green microalgae cultivation

    DEFF Research Database (Denmark)

    Valverde Perez, Borja

    completely counters the benefit of resource recovery. As an alternative, this thesis proposes a new fully biochemical resource recovery process, referred to as TRENS. The TRENS consists of an enhanced biological phosphorus removal and recovery (EBP2R) process combined with a photobioreactor (PBR). The EBP2R...... was reduced to sulphur reduced compounds, such as sulphide, by sulphate reducing bacteria (SRBs). Phosphorus removal was poor during the filamentous bulking event, which was a consequence of the interactions between SRBs and PAOs in the anaerobic phase. SRBs can compete with PAOs for volatile fatty acids...... under anaerobic conditions. Additionally, sulphide can inhibit phosphorus release by PAOs. As a result, PAOs were washed out from the systems. Filamentous bulking was mitigated and phosphorus removal was restored by reducing the anaerobic SRT of the SBR. However, this strategy failed when applied...

  7. Studies of Uranium Recovery from Tunisian Wet Process Phosphoric Acid

    OpenAIRE

    Naima Khleifia; Ahmed Hannachi; Noureddine Abbes

    2013-01-01

    The growing worldwide energy demand associated with several inter related complex environmental as well as economical issues are driving the increase of the share of uranium in energy mix. Subsequently, over the last few years, the interest for uranium extraction and recovery from unconventional resources has gained considerable importance. Phosphate rock has been the most suitable alternative source for the uranium recovery because of its uranium content. Solvent extraction has been found to...

  8. RECOVERY OF POLYHYDROXYALKANOATES (PHAs) FROM BACTERIAL CELLS USING ENZYMATIC PROCESS

    OpenAIRE

    S. Marsudi

    2012-01-01

    Polyhydroxyalkanoates (PHAs) are intracellular material accumulated by several bacteria. Commercial production of PHAs faces the issue of high production cost especially substrate cost and recovery/separation cost. An alternative to reduce the production cost is to use enzyme and or chemical to recover PHAs from bacterial cells. Recovery of PHAs from bacterial cells was done using enzyme, chemical, and a mixture of enzyme and chemical. Enzyme (s) and or chemical(s) were added into culture bro...

  9. Identification of existing waste heat recovery and process improvement technologies

    Energy Technology Data Exchange (ETDEWEB)

    Watts, R.L.; Dodge, R.E.; Smith, S.A.; Ames, K.R.

    1984-03-01

    General information is provided on waste heat recovery opportunities. The currently available equipment for high- and low-temperature applications are described. Other equipment related to wasteheat recovery equipment such as components, instruments and controls, and cleaning equipment is discussed briefly. A description of the microcomputer data base is included. Suppliers of waste heat equipment are mentioned throughout the report, with specific contacts, addresses, and telephone numbers provided in an Appendix.

  10. Development of novel processes for Cu concentrates without producing sulfuric acid; Hiryusan hasseigata no atarashii doshigen shori gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Awakura, Y.; Hirato, T. [Kyoto University, Kyoto (Japan)

    1997-02-01

    Studies are conducted to develop a new wet method for copper concentrates to replace the conventional dry smelting method for the settlement of problems involving the processing of impurities for environmental protection. A specimen of pyrites polycrystals is subjected to leaching at 80 {degree}C in a strongly acidic cupric solution. Findings are that the element sulfur generated in this process does not impede leaching and only approximately 4% of the sulfur is oxidized into sulfur ions; that the presence of more than 2g/liter of bromide ions produced during bromine-aid leaching of gold changes the structure of sulfur for the inhibition of leaching; that circulation of a bromine-containing leaching liquid is not desired since even a small amount of approximately 0.02mol/liter inhibits the leaching rate. Controlled potential electrolysis is performed for the anode in an acid solution containing CuCl, NaCl, and NaBr, for the observation of oxidation/reduction potentials predicted by Nernst`s equation. It is then disclosed that bromine is more effective than chlorine in gold leaching and that the solution potential during leaching agent regeneration enables the monitoring of solution constitution. 2 refs.

  11. A microencapsulation process of liquid mercury by sulfur polymer stabilization/solidification technology. Part I: Characterization of materials

    OpenAIRE

    López-Delgado, A.; López, F. A.; Alguacil, F. J.; Padilla, I; Guerrero, A

    2012-01-01

    European Directives consider mercury a priority hazardous substance due to its adverse effects on human health and the environment. In response to environmental concerns, a microencapsulation process has been developed within the European LIFE program as a long-term storage option for mercury. This process leads to the obtainment of a stable concrete-like sulfur matrix that allows the immobilization of mercury. The final product, in the form of a solid block containing up to 30 % Hg, exhibits...

  12. Sulfur Earth

    Science.gov (United States)

    de Jong, B. H.

    2007-12-01

    Variations in surface tension affect the buoyancy of objects floating in a liquid. Thus an object floating in water will sink deeper in the presence of dishwater fluid. This is a very minor but measurable effect. It causes for instance ducks to drown in aqueous solutions with added surfactant. The surface tension of liquid iron is very strongly affected by the presence of sulfur which acts as a surfactant in this system varying between 1.9 and 0.4 N/m at 10 mass percent Sulfur (Lee & Morita (2002), This last value is inferred to be the maximum value for Sulfur inferred to be present in the liquid outer core. Venting of Sulfur from the liquid core manifests itself on the Earth surface by the 105 to 106 ton of sulfur vented into the atmosphere annually (Wedepohl, 1984). Inspection of surface Sulfur emission indicates that venting is non-homogeneously distributed over the Earth's surface. The implication of such large variation in surface tension in the liquid outer core are that at locally low Sulfur concentration, the liquid outer core does not wet the predominantly MgSiO3 matrix with which it is in contact. However at a local high in Sulfur, the liquid outer core wets this matrix which in the fluid state has a surface tension of 0.4 N/m (Bansal & Doremus, 1986), couples with it, and causes it to sink. This differential and diapiric movement is transmitted through the essentially brittle mantle (1024 Pa.s, Lambeck & Johnson, 1998; the maximum value for ice being about 1030 Pa.s at 0 K, in all likely hood representing an upper bound of viscosity for all materials) and manifests itself on the surface by the roughly 20 km differentiation, about 0.1 % of the total mantle thickness, between topographical heights and lows with concomitant lateral movement in the crust and upper mantle resulting in thin skin tectonics. The brittle nature of the medium though which this movement is transmitted suggests that the extremes in topography of the D" layer are similar in range to

  13. Illness Insight and Recovery: How Important is Illness Insight in Peoples’ Recovery Process?

    DEFF Research Database (Denmark)

    Korsbek, Lisa

    2013-01-01

    . Sources Used:The writing is based on research literature related to illness insight and on personal recovery experiences.Conclusions and Implications for Practice: It is helpful to consider the integration of the issue of illness insight when addressing the questions and consequences of diagnosis...

  14. THE APPLICATION OF REVERSE FLOCCULATION METHOD IN HIGH SULFUR COAL DESULFURIZATION

    Institute of Scientific and Technical Information of China (English)

    王力; 陈鹏; 张素清

    1999-01-01

    The reverse flocculation method for removing pyritic sulfur from high sulfur coals has been conceptually developed and investigated. The tentative tests on China high sulfur coals have shown that this advanced physical separation technique can be very efficient in coal desulfurization, provided the process parameters are properly optimized. Under the circumstances of acquiring high coal recovery, the total sulfur rejection with four kinds of coal samples normally falls in the range 5?% to 71% by one-step reverse flocculation, and within the range 40% to 59% by one-step normal flocculation process.

  15. Modelling phosphorus (P), sulfur (S) and iron (Fe) interactions for dynamic simulations of anaerobic digestion processes.

    Science.gov (United States)

    Flores-Alsina, Xavier; Solon, Kimberly; Kazadi Mbamba, Christian; Tait, Stephan; Gernaey, Krist V; Jeppsson, Ulf; Batstone, Damien J

    2016-05-15

    This paper proposes a series of extensions to functionally upgrade the IWA Anaerobic Digestion Model No. 1 (ADM1) to allow for plant-wide phosphorus (P) simulation. The close interplay between the P, sulfur (S) and iron (Fe) cycles requires a substantial (and unavoidable) increase in model complexity due to the involved three-phase physico-chemical and biological transformations. The ADM1 version, implemented in the plant-wide context provided by the Benchmark Simulation Model No. 2 (BSM2), is used as the basic platform (A0). Three different model extensions (A1, A2, A3) are implemented, simulated and evaluated. The first extension (A1) considers P transformations by accounting for the kinetic decay of polyphosphates (XPP) and potential uptake of volatile fatty acids (VFA) to produce polyhydroxyalkanoates (XPHA) by phosphorus accumulating organisms (XPAO). Two variant extensions (A2,1/A2,2) describe biological production of sulfides (SIS) by means of sulfate reducing bacteria (XSRB) utilising hydrogen only (autolithotrophically) or hydrogen plus organic acids (heterorganotrophically) as electron sources, respectively. These two approaches also consider a potential hydrogen sulfide ( [Formula: see text] inhibition effect and stripping to the gas phase ( [Formula: see text] ). The third extension (A3) accounts for chemical iron (III) ( [Formula: see text] ) reduction to iron (II) ( [Formula: see text] ) using hydrogen ( [Formula: see text] ) and sulfides (SIS) as electron donors. A set of pre/post interfaces between the Activated Sludge Model No. 2d (ASM2d) and ADM1 are furthermore proposed in order to allow for plant-wide (model-based) analysis and study of the interactions between the water and sludge lines. Simulation (A1 - A3) results show that the ratio between soluble/particulate P compounds strongly depends on the pH and cationic load, which determines the capacity to form (or not) precipitation products. Implementations A1 and A2,1/A2,2 lead to a reduction in

  16. RECOVERY OF POLYHYDROXYALKANOATES (PHAs FROM BACTERIAL CELLS USING ENZYMATIC PROCESS

    Directory of Open Access Journals (Sweden)

    S. Marsudi

    2012-02-01

    Full Text Available Polyhydroxyalkanoates (PHAs are intracellular material accumulated by several bacteria. Commercial production of PHAs faces the issue of high production cost especially substrate cost and recovery/separation cost. An alternative to reduce the production cost is to use enzyme and or chemical to recover PHAs from bacterial cells. Recovery of PHAs from bacterial cells was done using enzyme, chemical, and a mixture of enzyme and chemical. Enzyme (s and or chemical(s were added into culture broth to disrupt cells after adjusting pH and temperature of the culture broth. Treatment by adding enzyme or chemical only into culture broth showed a low level of PHAs recovered from bacterial cells. Treatment by adding a mixture of enzymes and chemicals showed the best result among 22 examined combinations, i.e. a mixture of EDTA, lisozyme, papain enzyme, and SDS. This combination gave a PHA recovery of 65 % w/w.

  17. Control structure design for resource recovery using the enhanced biological phosphorus removal and recovery (EBP2R) activated sludge process

    DEFF Research Database (Denmark)

    Valverde Perez, Borja; Fuentes-Martínez, José Manuel; Flores Alsina, Xavier;

    2016-01-01

    structurefor the novel enhanced biological phosphorus removal and recovery (EBP2R) process, which is currentlyunder development. The aim of the EBP2R is to maximize phosphorus recovery through optimal greenmicro-algal cultivation, which is achieved by controlling the nitrogen to phosphorus ratio (N-to-P ratio......Nowadays, wastewater is considered as a set of resources to be recovered rather than a mixture of pollutantsthat should be removed. Many resource recovery schemes have been proposed, involving the useof novel technologies whose controllability is poorly studied. In this paper we present a control...... in the effluent (16.9 ± 0.07) and can recover about 72% of the influent phosphorus. The phosphorus recovered by the CFS is limited by the influent nitrogen (65% of the influent phosphorus load). Using the CFS configuration the effluent N-to-P ratio cannot be effectively controlled (16.45 ± 2.48). Therefore...

  18. Sedimentation of sulfuric acid in acid tars from current production

    Energy Technology Data Exchange (ETDEWEB)

    Denisova, T.L.; Frolov, A.F.; Aminov, A.N.; Novosel' tsev, S.P.

    1987-09-01

    Acid tars obtained in treating T-750, KhF-12, and I-8A oils were investigated for purposes of recovering sulfuric acid and asphalt binders from the compositions and of determining the effects of storage time on the recovery. The consumption and sedimentation levels of sulfuric acid during storage for different periods and at different temperatures were assessed. The characteristics of an asphalt binder obtained by neutralizing acid tar with a paste consisting of asphalts from deasphalting operations and slaked lime, followed by oxidation of the mixture with atmospheric air, were determined. The sulfuric acid recovered in the settling process could be burned in order to purify it of organic contaminants.

  19. A Cleaner Process for Selective Recovery of Valuable Metals from Electronic Waste of Complex Mixtures of End-of-Life Electronic Products.

    Science.gov (United States)

    Sun, Zhi; Xiao, Y; Sietsma, J; Agterhuis, H; Yang, Y

    2015-07-01

    In recent years, recovery of metals from electronic waste within the European Union has become increasingly important due to potential supply risk of strategic raw material and environmental concerns. Electronic waste, especially a mixture of end-of-life electronic products from a variety of sources, is of inherently high complexity in composition, phase, and physiochemical properties. In this research, a closed-loop hydrometallurgical process was developed to recover valuable metals, i.e., copper and precious metals, from an industrially processed information and communication technology waste. A two-stage leaching design of this process was adopted in order to selectively extract copper and enrich precious metals. It was found that the recovery efficiency and extraction selectivity of copper both reached more than 95% by using ammonia-based leaching solutions. A new electrodeposition process has been proven feasible with 90% current efficiency during copper recovery, and the copper purity can reach 99.8 wt %. The residue from the first-stage leaching was screened into coarse and fine fractions. The coarse fraction was returned to be releached for further copper recovery. The fine fraction was treated in the second-stage leaching using sulfuric acid to further concentrate precious metals, which could achieve a 100% increase in their concentrations in the residue with negligible loss into the leaching solution. By a combination of different leaching steps and proper physical separation of light materials, this process can achieve closed-loop recycling of the waste with significant efficiency. PMID:26061274

  20. BENCH-SCALE RECOVERY OF LEAD USING AN ELECTROMEMBRANE/CHELATION PROCESS

    Science.gov (United States)

    This report presents the results of a bench-scale treatability test to investigate key process parameters influencing an innovative chelation electrodeposition process for recovery of lead from contaminated sons. thylenediamine tetraacetic acid (EDTA) and diethylenetriamine penta...

  1. BENCH-SCALE RECOVERY OF LEAD USING AND ELECTRO- MEMBRANE/CHELATION PROCESS

    Science.gov (United States)

    This report presents the results of a bench-scale treatability test to investigate key process parameters influencing an innovative chelation electrodeposition process for recovery of lead from contaminated sons. thylenediamine tetraacetic acid (EDTA) and diethylenetriamine penta...

  2. Souls in Extremis: Enacting Processes of Recovery from Homelessness Among Older African American Women.

    Science.gov (United States)

    Moxley, David P; Washington, Olivia G M

    2016-06-01

    In a midwestern city of the USA, the authors implemented the Leaving Homelessness Intervention Research Project-and its eight subprojects-to further understand homelessness as experienced by older minority women, develop intervention strategies to facilitate the movement of the participants out of homelessness, and illuminate the women's recovery process. After reviewing the social issue of homelessness among older African American women in the USA, and offering a framework on recovery and qualitative themes of recovery among participants involved in the Telling My Story subproject, the authors present a four-factor model of recovery-focused practice. The model reflects two recovery paradigms: one that is responsive to the negative consequences people experience as a result of their exposure to extreme situations, such as homelessness, and a proactive one in which assistance is designed to help people in recovery advance their own self-development and move forward their process of individuation. PMID:26781673

  3. Recovery of thorium and uranium from monazite processing Liquor produced by INB/Caldas, M G, by solvent extraction

    International Nuclear Information System (INIS)

    This work describes the study of thorium and uranium recovery from sulfuric liquor generated in chemical monazite treatment by solvent extraction technique. The sulfuric liquor was produced by Industries Nuclear of Brazil - INB, Caldas - Minas Gerais State. The study was carried out in two steps: in the first the process variable were investigated through discontinuous experiments; in the second, the parameters were optimized by continuous solvent extraction experiments. The influence of the following process variables was investigated: type and concentration of extracting agents, contact time between phases and aqueous/organic volumetric ratio. Extractants used in this study included: Primene J M-T, Primene 81-R, Alamine 336 and Aliquat 336. Thorium and uranium were simultaneously extracted by a mixture of Primene J M-T and Alamine 336, into Exxsol D-100. The stripping was carried out by hydrochloric acid (HCl) 2.0 mol/L. The study was carried out at room temperature. After selected the best process conditions, two continuous experiments of extraction and stripping were carried out. In the first experiment a mixture of 0.15 mol/L Primene J M-T and 0.05 mol/L Alamine 336 were used. The second experiment was carried out using 0.15 mol/L Primene J M-T and 0.15 mol/L Alamine 336. Four extraction stages and five stripping stages were used in both experiments. The first experiment showed a ThU2 and U3O8 content in loaded strip solution of 34.3 g/L and 1.49 g/L respectively and 0.10 g/L Th)2 and 0.05 g/L U3O8 in the raffinate. In the second experiment a loaded strip solution with 29.3 g/L ThO2 and 0.94 g/L U3O8 was obtained. In this experiment, the metals content in raffinate was less than 0.001 g/L, indicating a thorium recovery over 99.9% and uranium recovery of 99.4%. (author)

  4. Decoupling of sulfur and nitrogen cycling due to biotic processes in a tropical rainforest

    Science.gov (United States)

    Yi-Balan, Simona A.; Amundson, Ronald; Buss, Heather L.

    2014-10-01

    We examined the terrestrial sulfur (S) cycle in the wet tropical Luquillo Experimental Forest (LEF), Puerto Rico. In two previously instrumented watersheds (Icacos and Bisley), chemical and isotopic measurements of carbon (C), nitrogen (N) and S were used to explore the inputs, in-soil processing, and losses of S through comparison to the N cycle. Additionally, the impact of soil forming factors (particularly climate, organisms, topography and parent material) on S cycling in this system was considered. Atmospheric inputs (δ34S values of 16.1 ± 2.8‰), from a mixture of marine and anthropogenic sources, delivered an estimated 2.2 g S/(m2yr) at Icacos, and 1.8 g S/(m2yr) at Bisley. Bedrock N and S inputs to soil were minimal. We estimated a hydrologic export of 1.7 ± 0.1 g S/(m2yr) at Icacos, and 2.5 ± 0.2 g S/(m2yr) at Bisley. Stream baseflow S isotope data revealed significant bedrock S in the hydrologic export at Bisley (with a distinctive δ34S values of 1.6 ± 0.7‰), but not at Icacos. Pore water data supported the co-occurrence of at least three major biological S-fractionating processes in these soils: plant uptake, oxidative degradation of organic S and bacterial sulfate reduction. The rates and relative importance of these processes varied in time and space. Vegetation litter was 3-5‰ depleted in 34S compared to the average pore water, providing evidence for fractionation during uptake and assimilation. Out of all abiotic soil forming factors, climate, especially the high rainfall, was the main driver of S biogeochemistry in the LEF by dictating the types and rates of processes. Topography appeared to impact S cycling by influencing redox conditions: C, N and S content decrease downslope at all sites, and the Bisley lower slope showed strongest evidence of bacterial sulfate reduction. Parent material type did not impact the soil S cycle significantly. To compare the fate of S and N in the soil, we used an advection model to describe the isotopic

  5. The Recovery Process Utilizing Erikson’s Stages of Human Development

    OpenAIRE

    Vogel-Scibilia, Suzanne E.; McNulty, Kathryn Cohan; Baxter, Beth; Miller, Steve; Dine, Max; Frese, Frederick J.

    2009-01-01

    Of current interest to the field are clinical frameworks that foster recovery. The authors offer a psycho-developmental model that parallels Erik Erikson’s theory of human development, and theorize that the process of psychiatric recovery involves a psychic reworking of these fundamental steps. Understanding recovery in this context allows the client and the practitioner of psychiatric rehabilitation to design and implement a coherent treatment strategy.

  6. Evaluation of a sulfur oxide chemical heat storage process for a steam solar electric plant

    Energy Technology Data Exchange (ETDEWEB)

    Dayan, J.; Lynn, S.; Foss, A.

    1979-07-01

    The purpose of this study was to develop and evaluate technically feasible process configurations for the use of the sulfur oxide system, 2 SO/sub 3/ reversible 2 SO/sub 2/ + O/sub 2/, in energy storage. The storage system is coupled with a conventional steam-cycle power plant. Heat for both the power plant and the storage system is supplied during sunlit hours by a field of heliostats focussed on a central solar receiver. When sunlight is not available, the storage system supplies the heat to operate the power plant. A technically feasible, relatively efficient configuration is proposed for incorporating this type of energy storage system into a solar power plant. Complete material and energy balances are presented for a base case that represents a middle range of expected operating conditions. Equipment sizes and costs were estimated for the base case to obtain an approximate value for the cost of the electricity that would be produced from such an installation. In addition, the sensitivity of the efficiency of the system to variations in design and operating conditions was determined for the most important parameters and design details. In the base case the solar tower receives heat at a net rate of 230 MW(t) for a period of eight hours. Daytime electricity is about 30 MW(e). Nighttime generation is at a rate of about 15 MW(e) for a period of sixteen hours. The overall efficiency of converting heat into electricity is about 26%. The total capital cost for the base case is estimated at about $68 million, of which about 67% is for the tower and heliostats, 11% is for the daytime power plant, and 22% is for the storage system. The average cost of the electricity produced for the base case is estimated to be about 11 cents/kW(e)-hr.

  7. Simultaneous nitrogen and phosphorus removal in the sulfur cycle-associated Enhanced Biological Phosphorus Removal (EBPR) process.

    Science.gov (United States)

    Wu, Di; Ekama, George A; Wang, Hai-Guang; Wei, Li; Lu, Hui; Chui, Ho-Kwong; Liu, Wen-Tso; Brdjanovic, Damir; van Loosdrecht, Mark C M; Chen, Guang-Hao

    2014-02-01

    Hong Kong has practiced seawater toilet flushing since 1958, saving 750,000 m(3) of freshwater every day. A high sulfate-to-COD ratio (>1.25 mg SO4(2-)/mg COD) in the saline sewage resulting from this practice has enabled us to develop the Sulfate reduction, Autotrophic denitrification and Nitrification Integrated (SANI(®)) process with minimal sludge production and oxygen demand. Recently, the SANI(®) process has been expanded to include Enhanced Biological Phosphorus Removal (EBPR) in an alternating anaerobic/limited-oxygen (LOS-EBPR) aerobic sequencing batch reactor (SBR). This paper presents further development - an anaerobic/anoxic denitrifying sulfur cycle-associated EBPR, named as DS-EBPR, bioprocess in an alternating anaerobic/anoxic SBR for simultaneous removal of organics, nitrogen and phosphorus. The 211 day SBR operation confirmed the sulfur cycle-associated biological phosphorus uptake utilizing nitrate as electron acceptor. This new bioprocess cannot only reduce operation time but also enhance volumetric loading of SBR compared with the LOS-EBPR. The DS-EBPR process performed well at high temperatures of 30 °C and a high salinity of 20% seawater. A synergistic relationship may exist between sulfur cycle and biological phosphorus removal as the optimal ratio of P-release to SO4(2-)-reduction is close to 1.0 mg P/mg S. There were no conventional PAOs in the sludge. PMID:24342048

  8. Removal of organic and inorganic sulfur from Ohio coal by combined physical and chemical process. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Attia, Y.A.; Zeky, M.El.; Lei, W.W.; Bavarian, F.; Yu, S. [Ohio State Univ., Columbus, OH (United States). Dept. of Materials Science and Engineering

    1989-04-28

    This project consisted of three sections. In the first part, the physical cleaning of Ohio coal by selective flocculation of ultrafine slurry was considered. In the second part, the mild oxidation process for removal of pyritic and organic sulfur.was investigated. Finally, in-the third part, the combined effects of these processes were studied. The physical cleaning and desulfurization of Ohio coal was achieved using selective flocculation of ultrafine coal slurry in conjunction with froth flotation as flocs separation method. The finely disseminated pyrite particles in Ohio coals, in particular Pittsburgh No.8 seam, make it necessary to use ultrafine ({minus}500 mesh) grinding to liberate the pyrite particles. Experiments were performed to identify the ``optimum`` operating conditions for selective flocculation process. The results indicated that the use of a totally hydrophobic flocculant (FR-7A) yielded the lowest levels of mineral matters and total sulfur contents. The use of a selective dispersant (PAAX) increased the rejection of pyritic sulfur further. In addition, different methods of floc separation techniques were tested. It was found that froth flotation system was the most efficient method for separation of small coal flocs.

  9. The Waste - heat Recovery and Equipment Selection of the 200kt/a - Output Plant of the Sulfuric Acid by Pyrite Roasting%年产20万t硫铁矿制酸装置的余热回收和相关设备选型

    Institute of Scientific and Technical Information of China (English)

    陈雄

    2011-01-01

    介绍了200kt/a硫铁矿制酸的余热回收和利用,主要分为高温、中温、低温余热,并介绍了相应的设备选型过程。%The waste- heat recovery of the 200kt/a- output plant of the sulfuric acid by pyrite roasting was introduced, including high temperature waste- heat, middle temperature waste- heat, low temperature waste - heat. And the process of equipment selection was also mentioned.

  10. Adaptive control of sulphur recovery units

    International Nuclear Information System (INIS)

    Efficient removal of sulfur is important in the operation of a gas processing plant. Control of the sulfur recovery unit (SRU) is difficult using conventional controllers due to variations in gas composition and time delays within the recovery process itself. Adaptive controllers are well-suited to the problem of handling lengthy and varying process time delays. Adaptive controllers use a mathematical model of the process, including time delay, to forecast a process response. A new approach to adaptive control is presented which uses orthogonal functions to model the process. The transfer function required for implementing the controller can then be identified using a minimum of historical process information. The controller can do this while it controls the process, automatically adapting to changes in gain, time constants, or time delay in order to maintain optimal control. The sulfur recovery process is explained and test results are presented showing the performance of the new adaptive controller compared to the performance of a conventional controller in recovering sulfur and reducing SO2 emissions. The adaptive controller had a 38% lower standard deviation and the improved tail gas ratio control alone is estimated to have resulted in a 0.4% increase in sulfur recovery efficiency. Using the adaptive controller on other stages of the plant could raise the total improvement to 0.6-0.7%. Additional benefits of using the new controller include increased production, avoidance of major capital and operating expense to achieve increases in recovery efficiency, avoidance of penalties for exceeding sulfur emission limits, and extension of catalyst bed life. 3 refs., 8 figs., 2 tabs

  11. Uranium recovery process with protection for ion exchange resin

    International Nuclear Information System (INIS)

    The ion-exchange resins in uranium recovery operations are protected from oxidative degradation caused by contact with hydrogen peroxide. A guard chamber is positioned in the elution circuit so that barren eluant will flow through the chamber. The guard chamber contains catalytic material, e.g. activated carbon, which decomposes hydrogen peroxide upon contact into water and oxygen. The barren eluant, after it passes through the catalytic material, is used to make up fresh eluant for reuse in the recovery method without the risk of the fresh eluant causing oxidative degradation of the resins. The concentration of hydrogen peroxide may be determined by monitoring the amount of oxygen generated when the hydrogen peroxide is catalytically decomposed

  12. Petroleum recovery process utilizing formaldehyde-sulfite-reacted polyacrylamide

    Energy Technology Data Exchange (ETDEWEB)

    Norton, C.J.; Falk, D.O.

    1973-09-25

    Micellar slugs followed by thickened water floods were injected into Berea cores (20.4 percent porosity, 398.4 md permeability, see Patent 3,692,113 for pretreatment) for enhanced oil recovery. About 61.1 percent residual oil was produced when the polymer in the thickened water was sulfomethylated hydrolyzed polyacrylamide. However, use of the conventional unhydrolyzed polyacrylamide recovered only 27.7 percent residual oil.

  13. Processing of spent nickel catalyst for fat recovery

    OpenAIRE

    Ibrahim Nasir, Mohammad

    2002-01-01

    Spent nickel catalyst (SNC) have the potential of insulting the quality of the environment in a number of ways. The disposal of SNC will have a pollution effect. Optimum recovery of fat from SNC , could save the environment and reduce the oil loss. Hexane has been the solvent of choice for oil extraction. Alternative solvents that are considered safer have been evaluated. Hexane, isopropanol, ethanol, and heptane were examined using soxhlet extraction. While hexane was more efficient in oil r...

  14. 降低硫黄装置尾气SO2排放浓度的探索%Study on reduction of tail gas SO2 emission of sulfur recovery unit

    Institute of Scientific and Technical Information of China (English)

    王有义; 张宝庆

    2011-01-01

    The 20,000 TPY sulfur recovery unit in SINOPEC Tahe Company was started up in December 7, 2004, In more than one year' s operation after start-up, the tail gas SO2 emission of sulfur recovery unit failed to meet the design specifications, and the SO2 emission exceeded standard specifications. After extensive study , four major causes were located, I. E. 1) imprecise air supply for Claus system, 2) large diameter of packings in tail gas absorber and lower design solvent recycle rate, 3) failure to cool down high-temperature solvent, 4) poor lean solvent quality because of overload of solvent regeneration. To solve these problems, the unit was revamped in the turnaround in May, 2006. The SO2 concentration in emission was 500-803 mg/m3 after revamping. In July 1, 2011, China Environmental Protection Bureau began to implement new emission standard, which is lower than 400 mg/m for SO2 in tail gas of sulfur recovery unit. To meet the new standard, the off-specification causes were analyzed and process parameters were adjusted. As the result, the SO2 emission was gradually lowered and was finally reduced to 300 mg/m .%中国石油化工股份有限公司塔河分公司2×104 t/a硫黄回收装置于2004年10月底建成,12月7日开工,开工后经一年多调整工艺操作,硫黄装置尾气中SO2排放浓度达不到设计值,超标排放,经查找原因,有4大影响因素:①克劳斯系统不能精确配风;②尾气吸收塔填料直径大,溶剂循环量设计偏小;③溶剂温度高,冷却不下;④溶剂再生超负荷,造成贫液质量差.针对上述4个问题在2006年5月大修时进行技改,开工后尾气中SO2排放质量浓度为500 ~ 803 mg/m3.2011年国家环保部要求制硫尾气中SO2于7月1日后实施新标准400 mg/m3以下.根据这一标准,经分析原因及针对性调整工艺参数,分段查找影响因素,逐步修正工艺参数,使制硫尾气中SO2排放浓度逐步下降,最终使尾气中SO2

  15. Platinum group metal recovery and catalyst manufacturing process

    Energy Technology Data Exchange (ETDEWEB)

    Chung, H. S.; Kim, Y. S.; Yoo, J. H.; Lee, H. S.; Ahn, D. H.; Kim, K. R.; Lee, S. H.; Paek, S. W.; Kang, H. S.

    1998-03-01

    The fission product nuclides generated during the irradiation of reactor fuel include many useful elements, among them platinum group metal such as ruthenium, rhodium and palladium which are of great industrial importance, occur rarely in nature and are highly valuable. In this research, the authors reviewed various PGM recovery methods. Recovery of palladium from seven-component simulated waste solution was conducted by selective precipitation method. The recovery yield was more than 99.5% and the purity of the product was more than 99%. Wet-proof catalyst was prepared with the recovered palladium. The specific surface area of the catalyst support was more than 400 m{sup 2}/g. The content of palladium impregnated on the support was 10 wt.%. Hydrogen isotope exchange efficiency of 93 % to equilibrium with small amount of the catalyst was obtained. It was turned out possible to consider using such palladium or other very low active PGM materials in applications where its actively is unimportant as in nuclear industries. (author). 63 refs., 38 tabs., 36 figs.

  16. Platinum group metal recovery and catalyst manufacturing process

    International Nuclear Information System (INIS)

    The fission product nuclides generated during the irradiation of reactor fuel include many useful elements, among them platinum group metal such as ruthenium, rhodium and palladium which are of great industrial importance, occur rarely in nature and are highly valuable. In this research, the authors reviewed various PGM recovery methods. Recovery of palladium from seven-component simulated waste solution was conducted by selective precipitation method. The recovery yield was more than 99.5% and the purity of the product was more than 99%. Wet-proof catalyst was prepared with the recovered palladium. The specific surface area of the catalyst support was more than 400 m2/g. The content of palladium impregnated on the support was 10 wt.%. Hydrogen isotope exchange efficiency of 93 % to equilibrium with small amount of the catalyst was obtained. It was turned out possible to consider using such palladium or other very low active PGM materials in applications where its actively is unimportant as in nuclear industries. (author). 63 refs., 38 tabs., 36 figs

  17. Emission characteristics of nitrogen- and sulfur-containing odorous compounds during different sewage sludge chemical conditioning processes

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Huan [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Luo, Guang-Qian; Hu, Hong-Yun [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); Zhang, Qiang; Yang, Jia-Kuan [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Yao, Hong, E-mail: hyao@hust.edu.cn [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer NH{sub 3}, SO{sub 2}, H{sub 2}S and COS are emitted during different sludge conditioning processes. Black-Right-Pointing-Pointer H{sub 2}S and SO{sub 2} generation increase in the acidic environment created by H{sub 2}SO{sub 4}. Black-Right-Pointing-Pointer Fenton peroxidation facilitates the formation of COS. Black-Right-Pointing-Pointer CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. Black-Right-Pointing-Pointer CaO leads to the conversion of free ammonia or protonated amine to volatile NH{sub 3}. - Abstract: Chemical conditioners are often used to enhance sewage sludge dewaterability through altering sludge properties and flocs structure, both affect odorous compounds emissions not only during sludge conditioning but also in subsequent sludge disposal. This study was to investigate emission characteristics of ammonia (NH{sub 3}), sulfur dioxide (SO{sub 2}), hydrogen sulfide (H{sub 2}S) and carbonyl sulfide (COS) generated from sewage sludge conditioned by three representative conditioners, i.e., organic polymers, iron salts and skeleton builders, F-S (Fenton's reagent and skeleton builders) composite conditioner. The results demonstrate that polyacrylamide (PAM) has an insignificant effect on emission characteristics of nitrogen- and sulfur-containing odorous compounds, because the properties, sulfur and nitrogen speciations are similar in PAM-conditioned sludge and raw sludge (RS). Significant increases of SO{sub 2} and H{sub 2}S emissions in the H{sub 2}SO{sub 4} conditioning process were observed due to the accelerated decomposition of sulfur-containing amino acids in acidic environment. Fenton peroxidation facilitates the formation of COS. CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. However, under strong alkaline conditions, free ammonia or protonated amine in sludge can be easily converted to volatile ammonia, resulting in a significant

  18. Waste heat and water recovery opportunities in California tomato paste processing

    International Nuclear Information System (INIS)

    Water and energy efficiency are important for the vitality of the food processing industry as demand for these limited resources continues to increase. Tomato processing, which is dominated by paste production, is a major industry in California – where the majority of tomatoes are processed in the United States. Paste processing generates large amounts of condensate as moisture is removed from the fruit. Recovery of the waste heat in this condensate and reuse of the water may provide avenues to decrease net energy and water use at processing facilities. However, new processing methods are needed to create demand for the condensate waste heat. In this study, the potential to recover condensate waste heat and apply it to the tomato enzyme thermal inactivation processing step (the hot break) is assessed as a novel application. A modeling framework is established to predict heat transfer to tomatoes during the hot break. Heat recovery and reuse of the condensate water are related to energy and monetary savings gained through decreased use of steam, groundwater pumping, cooling towers, and wastewater processing. This analysis is informed by water and energy usage data from relevant unit operations at a commercial paste production facility. The case study indicates potential facility seasonal energy and monetary savings of 7.3 GWh and $166,000, respectively, with most savings gained through reduced natural gas use. The sensitivity of heat recovery to various process variables associated with heat exchanger design and processing conditions is presented to identify factors that affect waste heat recovery. - Highlights: • The potential to recovery waste heat in tomato paste processing is examined. • Heat transfer from evaporator condensate to tomatoes in the hot break is modeled. • Processing facility data is used in model to predict heat recovery energy savings. • The primary benefit of heat recovery is reduced use of natural gas in boilers. • Reusing

  19. Experimental analysis of an adsorption refrigerator with mass and heat-pipe heat recovery process

    International Nuclear Information System (INIS)

    Highlights: ► We develop one heat pipe type adsorption refrigerator. ► New compound adsorbent of CaCl2/activated carbon–ammonia can work more effectively. ► Combined mass recovery-heat pipe heat recovery can improve adsorption performance. ► Combined mass recovery-heat pipe heat recovery can reduce cycle time. - Abstract: A heat pipe type adsorption refrigerator system is proposed and investigated, which can be powered by solar energy or waste heat of engine. The study assesses the performance of compound adsorbent (CaCl2 and activated carbon)–ammonia adsorption refrigeration cycle with different orifice sets and different mass and heat recovery processes by experimental prototype machine. Specific cooling power (SCP) and coefficient of performance (COP) were calculated with experimental data to analyze the influences of operating condition. The results show that the jaw opening of the hand needle nozzle can influence the adsorption performance obviously and the thermostatic expansion valve (TEV) is effective in the intermediate cycle time in the adsorption refrigeration system. The SCP of the cycle with the mass-heat recovery together (combined recovery process) is superior to that of the conventional cycles with mass recovery or heat recovery independently.

  20. Advances in uranium ore processing and recovery from non-conventional resources

    International Nuclear Information System (INIS)

    The main topics covered by the technical sessions were: in situ and heap leaching, improvements in conventional acid and alkaline uranium ore processing, recovery of uranium from wet-process phosphoric acid and recovery of uranium from coal and from natural waters. The technical sessions concluded with three panel discussions dealing with pre-concentration and benefication, in situ and heap leaching, and recovery of uranium from wet-process phosphoric acid. The present volume includes 18 of the 27 presented papers. A separate abstract was prepared for each of these papers

  1. Research process of lithium-sulfur batteries%锂硫电池正极材料研究进展

    Institute of Scientific and Technical Information of China (English)

    罗晓华; 余瑞芳

    2014-01-01

    锂硫电池是一类极具发展前景的高容量储能体系,将是下一代电动汽车以及混合电动汽车的化学能源。通过十余年的研究和开发,虽然对其电化学过程中复杂反应机理还没有完整系统的理论描述,但是围绕锂硫电池的研究取得了很多成果。回顾了过去十余年在锂硫电池正极材料领域取得的研究成果,介绍了锂硫电池正极材料的研究现状,分析了该体系的缺陷和存在的问题,并展望了今后锂硫电池的研究方向。%Lithium-sulfur battery is a high capacity energy storage system with bright future,and it is considered as the next generation portable energy supply device for electric vehicle(EV)and hybrid electric vehicle(HEV).Through decades of research and development,people understand the system stepwisely.The electrochemistry mechanism of sulfur cathode is very complex and hard to examine,which is the key point to develop lithium-sulfur battery.Although there are many unknown mechanism in the electrochemical process of charge/discharge of the lithium sul-fur battery,some achievements have been made on the development of cathode materials which provide various sources to study.The achievements on lithium sulfur battery in the past decade from the respects of lithium sulfur battery system and cathode materials are reviewed in this pa-per.The weaknesses are revealed and the future is prospected.

  2. Sulfur and carbon geochemistry of the Santa Elena peridotites: Comparing oceanic and continental processes during peridotite alteration

    Science.gov (United States)

    Schwarzenbach, Esther M.; Gill, Benjamin C.; Gazel, Esteban; Madrigal, Pilar

    2016-05-01

    Ultramafic rocks exposed on the continent serve as a window into oceanic and continental processes of water-peridotite interaction, so called serpentinization. In both environments there are active carbon and sulfur cycles that contain abiogenic and biogenic processes, which are eventually imprinted in the geochemical signatures of the basement rocks and the calcite and magnesite deposits associated with fluids that issue from these systems. Here, we present the carbon and sulfur geochemistry of ultramafic rocks and carbonate deposits from the Santa Elena ophiolite in Costa Rica. The aim of this study is to leverage the geochemistry of the ultramafic sequence and associated deposits to distinguish between processes that were dominant during ocean floor alteration and those dominant during low-temperature, continental water-peridotite interaction. The peridotites are variably serpentinized with total sulfur concentrations up to 877 ppm that is typically dominated by sulfide over sulfate. With the exception of one sample the ultramafic rocks are characterized by positive δ34Ssulfide (up to + 23.1‰) and δ34Ssulfate values (up to + 35.0‰). Carbon contents in the peridotites are low and are isotopically distinct from typical oceanic serpentinites. In particular, δ13C of the inorganic carbon suggests that the carbon is not derived from seawater, but rather the product of the interaction of meteoric water with the ultramafic rocks. In contrast, the sulfur isotope data from sulfide minerals in the peridotites preserve evidence for interaction with a hydrothermal fluid. Specifically, they indicate closed system abiogenic sulfate reduction suggesting that oceanic serpentinization occurred with limited input of seawater. Overall, the geochemical signatures preserve evidence for both oceanic and continental water-rock interaction with the majority of carbon (and possibly sulfate) being incorporated during continental water-rock interaction. Furthermore, there is

  3. Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes

    Energy Technology Data Exchange (ETDEWEB)

    Yorstos, Yannis C.

    2003-03-19

    The report describes progress made in the various thrust areas of the project, which include internal drives for oil recovery, vapor-liquid flows, combustion and reaction processes and the flow of fluids with yield stress.

  4. Efficient ethanol recovery from yeast fermentation broth with integrated distillation-membrane process

    Science.gov (United States)

    A hybrid process integrating vapor stripping with vapor compression and vapor permeation membrane separation, termed Membrane Assisted Vapor Stripping (MAVS), was evaluated for recovery and dehydration of ethanol from aqueous solution as an alternative to conventional distillatio...

  5. Efficient ethanol recovery from fermentation broths with integrated distillation-membrane process

    Science.gov (United States)

    The energy demand of distillation-molecular sieve systems for ethanol recovery/dehydration can be significant, particularly for dilute solutions. An alternative process integrating vapor stripping (like a beer still) with vapor compression and a vapor permeation membrane separati...

  6. Local Risk-Minimization for Defaultable Claims with Recovery Process

    International Nuclear Information System (INIS)

    We study the local risk-minimization approach for defaultable claims with random recovery at default time, seen as payment streams on the random interval [0,τ∧T], where T denotes the fixed time-horizon. We find the pseudo-locally risk-minimizing strategy in the case when the agent information takes into account the possibility of a default event (local risk-minimization with G-strategies) and we provide an application in the case of a corporate bond. We also discuss the problem of finding a pseudo-locally risk-minimizing strategy if we suppose the agent obtains her information only by observing the non-defaultable assets.

  7. Metals recovery of spent household batteries using a hydrometallurgical process

    International Nuclear Information System (INIS)

    The objective of the work is to study a method for metals recovery from a sample composed by a mixture of the main types of spent household batteries. Segregation of the main metals is investigated using a treatment route consisting of the following steps: manual identified and dismantling, grinding, electric furnace reduction, acid leaching and selective precipitation with sodium hydroxide with and without hydrogen peroxide. Before and after precipitations the solutions had been analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP/OES) and the precipitated analyzed by Scanning Electron Microscopy (SEM) with Spectrometry of Energy Dispersion Spectroscopy (EDS). The results had indicated that the great majority of metals had been precipitated in pHs studied, also had co-precipitation or simultaneous precipitation of metals in some pHs. (author)

  8. Local Risk-Minimization for Defaultable Claims with Recovery Process

    Energy Technology Data Exchange (ETDEWEB)

    Biagini, Francesca, E-mail: biagini@mathematik.uni-muenchen.de [LMU, Department of Mathematics (Germany); Cretarola, Alessandra, E-mail: alessandra.cretarola@dmi.unipg.it [Universita degli Studi di Perugia, Dipartimento di Matematica e Informatica (Italy)

    2012-06-15

    We study the local risk-minimization approach for defaultable claims with random recovery at default time, seen as payment streams on the random interval [0,{tau} Logical-And T], where T denotes the fixed time-horizon. We find the pseudo-locally risk-minimizing strategy in the case when the agent information takes into account the possibility of a default event (local risk-minimization with G-strategies) and we provide an application in the case of a corporate bond. We also discuss the problem of finding a pseudo-locally risk-minimizing strategy if we suppose the agent obtains her information only by observing the non-defaultable assets.

  9. Acceptance and Avoidance Processes at Different Levels of Psychological Recovery from Enduring Mental Illness

    Science.gov (United States)

    Siqueira, Vinicius R.; Oades, Lindsay G.

    2015-01-01

    Objective. This study examined the use of psychological acceptance and experiential avoidance, two key concepts of Acceptance and Commitment Therapy (ACT), in the psychological recovery process of people with enduring mental illness. Method. Sixty-seven participants were recruited from the metropolitan, regional, and rural areas of New South Wales, Australia. They all presented some form of chronic mental illness (at least 12 months) as reflected in DSM-IV Axis I diagnostic criteria. The Acceptance and Action Questionnaire (AAQ-19) was used to measure the presence of psychological acceptance and experiential avoidance; the Recovery Assessment Scale (RAS) was used to examine the levels of psychological recovery; and the Scales of Psychological Well-Being was used to observe if there are benefits in utilizing psychological acceptance and experiential avoidance in the recovery process. Results. An analysis of objectively quantifiable measures found no clear correlation between the use of psychological acceptance and recovery in mental illness as measured by the RAS. The data, however, showed a relationship between psychological acceptance and some components of recovery, thereby demonstrating its possible value in the recovery process. Conclusion. The major contribution of this research was the emerging correlation that was observed between psychological acceptance and positive levels of psychological well-being among individuals with mental illness. PMID:26576412

  10. Charcoal adsorption studies for separation of entrained DNPPA from phosphoric acid in uranium recovery process

    International Nuclear Information System (INIS)

    Recovery of uranium from phosphoric acid is achieved by a two cycle solvent extraction process where organophosphorus extractants such as D2EHPA, di-nonyl phenyl phosphoric acid (DNPPA), TBP and TOPO are used. DNPPA+TOPO synergistic extractant mixture is employed for U recovery from MGA. These extractants exhibits different solubility in various aqueous solutions during the solvent extraction process. It is essential to recover the solvents firstly, to improve the process economy and secondly to prevent environmental pollution. Earlier work carried out by the diluent wash method for entrained solvent recovery has been reported. It was observed that diluent wash is feasible only in the acidic aqueous solutions. Investigations were out to study entrained solvent recovery from both alkaline as well as acidic aqueous solutions using activated charcoal adsorption method

  11. Digestion of Bangka monazite with sulfuric acid

    International Nuclear Information System (INIS)

    Technology of Bangka monazite processing with alkaline method has been mastered by PPGN BATAN with the product in the form of RE (Rare Earth) which is contain U < 2 ppm and Th 12 - 16 ppm. Hence, as comparator, the research of Bangka monazite processing with acid method using sulfuric acid has been done. The aim of this research is to obtain the optimal condition of Bangka monazite's digestion using sulfuric acid so that all elements contained in the monazite that are U, Th, RE, PO4 dissolved as much as possible. The research parameter's arc monazite particle's size, sulfuric acid consumption (weight ratio of monazite ore : sulfuric acid), digestion temperature, digestion time and consumption of wash water. The results showed that the optimal conditions of digestion are 250+ 325 mesh of monazite particle's size, 1 : 2.5 of weight ratio of monazite ore: sulfuric acid, 190°C of digestion temperature, 3 hours of digestion time and 8 times of weight monazite's feed of wash water with the recovery of digested U = 99.90 %, Th = 99.44 %, RE = 98.64 % and PO4 = 99.88 %. (author)

  12. Sulfomethylated lignosulfonates as additives in oil recovery processes involving chemical recovery agents

    Energy Technology Data Exchange (ETDEWEB)

    Kalfoglou, G.

    1979-10-30

    A process for producing petroleum from subterranean formations is disclosed wherein production from the formation is obtained by driving a fluid from an injection well to a production well. The process involves injecting via the injection well into the formation an aqueous solution of sulfomethylated lignosulfonate salt as a sacrificial agent to inhibit the deposition of surfactant and/or polymer on the reservoir matrix. The process may best be carried out by injecting the sulfomethylated lignosulfonates into the formation through the injection well mixed with either a polymer, a surfactant solution and/or a micellar dispersion. This mixture would then be followed by a drive fluid such as water to push the chemicals to the production well.

  13. Sulfomethylated lignosulfonates as additives in oil recovery processes involving chemical recovery agents

    Energy Technology Data Exchange (ETDEWEB)

    Kalfoglou, G.

    1981-05-26

    A process for producing petroleum from subterranean formations is disclosed wherein production from the formation is obtained by driving a fluid from an injection well to a production well. The process involves injecting via the injection well into the formation an aqueous solution of sulfomethylated lignosulfonate salt as a sacrificial agent to inhibit the deposition of surfactant and/or polymer on the reservoir matrix. The process may best be carried out by injecting the sulfomethylated lignosulfonates into the formation through the injection well mixed with either a polymer, a surfactant solution and/or a micellar dispersion. This mixture would then be followed by a drive fluid such as water to push the chemicals to the production well.

  14. Aquatic worm reactor for improved sludge processing and resource recovery

    OpenAIRE

    Hendrickx, T.L.G.

    2009-01-01

    Municipal waste water treatment is mainly achieved by biological processes. These processes produce huge volumes of waste sludge (up 1.5 million m3/year in the Netherlands). Further processing of the waste sludge involves transportation, thickening and incineration. A decrease in the amount of waste sludge would be both environmentally and economically attractive. Aquatic worms can be used to reduce the amount of waste sludge. After predation by the worms, the amount of final sludge is lower....

  15. Combined TRU--Sr extraction/recovery process

    International Nuclear Information System (INIS)

    Reported is the development and testing of a new solvent extraction/recover process for extracting and selectively partitioning U, TRUs (Np, Pu, Am), 90Sr, and 99Tc from dissolved sludge waste obtained from Hanford storage tanks. Objectives were to minimize the amount waste that must be vitrified and to reduce the cost of chemical pretreatment. The new process is a combination of TRUEX and the recently developed SREX (strontium extraction) process. A flowsheet is included. 5 figs

  16. Measures for waste water management from recovery processing of Zhushanxia uranium deposit

    International Nuclear Information System (INIS)

    Measures for waste water management from recovery processing of Zhushanxia uranium deposit of Wengyuan Mine is analyzed, which include improving process flow, recycling process water used in uranium mill as much as possible and choosing a suitable disposing system. All these can decrease the amount of waste water, and also reduce costs of disposing waste water and harm to environment

  17. Radiation-induced recovery processes in cultured marsupial cells

    International Nuclear Information System (INIS)

    The ultraviolet sensitivity of Potorous tridactylus male kidney (PtK-2) cells is markedly increased by post irradiation treatment for 24 h with 5 μM emetine of with 5 μM cycloheximide or with the RNA polymerase II inhibitor 5,6-dichloro-1-β-ribofuranosylbenzimidazole at 50 μM. All 3 treatments give the same sensitivity, while unirradiated cells are little affected. Shortening the time of treatment, of delaying application of the drugs decreases their effects on the same time schedule. Preiiradiation of cells, with no drug treatment in the following 8 h, diminishes the sensitivity to a subsequent irradiation with protein synthesis blocked afterwards. Photoreactivation immediately following such preiiradiation eliminated its desensitizing effect. Inhibiting protein synthesis after irradiation also markedly reduces the frequency of UV-induced mutants in the surviving population. These facts suggest that gene expression in the period following iradiation facilitates recovery from radiation damage, with an increased probability of mutation, reminiscent of the 'SOS response' in Escherichia coli. (author). 29 refs.; 5 figs.; 3 tabs

  18. 某铁矿尾矿综合回收工艺研究%Study on the Comprehensive Recovery Process of Tailings from a Certain Iron Mine

    Institute of Scientific and Technical Information of China (English)

    张亚辉; 施维; 周超; 李妍; 季婷婷

    2011-01-01

    The chemical composition of tailings sands with Fe 21.77%, Cu O.20%, S 1.03 % and the phase of main mineral were analyzed, and then a process of low intensity magnetic separation-high intensity magnetic separation-reduction roasting-low intensity magnetic separation-bulk flotation of copper and sulfur-separation of copper and sulfur is made to get Fe, Cu and S.Under the optimal technical conditions obtained from tests, iron concentrate with a yield of 20.39%, Fe grade of 61.62%, Fe recovery of 57.71%, copper concentrate with Cu grade of 14.57 % , Cu recovery of 3.21% , and Sulfur concentrate with S grade of 38.21% and S recovery of 10.95% are achieved.The conclusion is that the recovery of iron minerals reaches remarkable economic benefits, but the recovery of copper and sulfide minerals are not ideal.%对某含铁21.77%、铜0.20%、硫1.03%的尾矿砂的化学成分及主要矿物物相进行了分析,并针对性地制定了铁、铜、硫回收试验的弱磁-强磁-还原焙烧-弱磁-铜硫混浮-铜硫分离原则流程,在试验确定的最优工艺技术条件下,获得了产率20.39%、铁品位61.62%、回收率57.71%的铁精矿,铜品位14.57%、回收率3.21%的铜精矿,硫品位38.21%、回收率10.95%的硫精矿.得出铁矿物回收经济效益显著、铜硫矿物回收效益不理想的结论.

  19. Ultrasonic processing for recovery of chicken erythrocyte hemoglobin

    Science.gov (United States)

    Hemoglobin from chicken blood has been shown to be a good substitute for synthetic polymeric flocculants. One stage of processing the blood entails breaking open the cells and releasing the cytoplasmic contents; in the present study, we investigate the use of ultrasonic processing at this stage. Was...

  20. Controlled Sulfurization Process for the Synthesis of Large Area MoS2 Films and MoS2/WS2 Heterostructures

    OpenAIRE

    Chiappe, Daniele; Asselberghs, Inge; Sutar, Surajit; Iacovo, Serena; Afanas'ev, Valeri; Stesmans, Andre; Balaji, Yashwanth; Peters, Lisanne; Heyne, Markus; Mannarino, Manuel; Vandervorst, Wilfried; Sayan, Safak; Huyghebaert, Cedric; Caymax, Matty; Heyns, Marc

    2015-01-01

    Large area MoS2 films with tunable physical-chemical properties are grown on dielectric substrates by annealing of ultrathin Mo layers in the presence of a sulfur-containing gaseous precursor. Different growth conditions are found to have a significant impact on material properties, including chemical composition, roughness, and grain sizes, thus shedding light on critical parameters that govern sulfurization processes for the synthesis of large area 2D transition metal dichalcogenides. Optim...

  1. Modelling phosphorus (P), sulfur (S) and iron (Fe) interactions for dynamic simulations of anaerobic digestion processes

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Solon, Kimberly; Kazadi Mbamba, Christian;

    2016-01-01

    This paper proposes a series of extensions to functionally upgrade the IWA Anaerobic Digestion Model No. 1 (ADM1) to allow for plant-wide phosphorus (P) simulation. The close interplay between the P, sulfur (S) and iron (Fe) cycles requires a substantial (and unavoidable) increase in model...... reduces the quantities of struvite (XMgNH4PO4) and calcium phosphate (XCa3(PO4)2) that are formed due to its higher affinity for phosphate anions. This study provides a detailed analysis of the different model assumptions, the effect that operational/design conditions have on the model predictions...

  2. Optimal operation of integrated processes. Studies on heat recovery systems

    Energy Technology Data Exchange (ETDEWEB)

    Glemmestad, Bjoern

    1997-12-31

    Separators, reactors and a heat exchanger network (HEN) for heat recovery are important parts of an integrated plant. This thesis deals with the operation of HENs, in particular, optimal operation. The purpose of heat integration is to save energy, but the HEN also introduces new interactions and feedback into the overall plant. A prerequisite for optimisation is that there are extra degrees of freedom left after regulatory control is implemented. It is shown that extra degrees of freedom may not always be utilized for energy optimisation, and a quantitative expression for the degrees of freedom that can be so utilized are presented. A simplified expression that is often valid is also deduced. The thesis presents some improvements and generalisations of a structure based method that has been proposed earlier. Structural information is used to divide possible manipulations into three categories depending on how each manipulation affects the utility consumption. By means of these categories and two heuristic rules for operability, the possible manipulations are ordered in a priority table. This table is used to determine which manipulation should be preferred and which manipulation should be selected if an active manipulation is saturated. It is shown that the method may correspond to split-range control. A method that uses parametric information in addition to structural information is proposed. In this method, the optimal control structure is found through solving an integer programming problem. The thesis also proposes a method that combines the use of steady state optimisation and optimal selection of measurements. 86 refs., 46 figs., 8 tabs.

  3. Recovery of uranium from wet-process phosphoric acid

    International Nuclear Information System (INIS)

    Uranium values are recovered as uranyl peroxide from wet process phosphoric acid by a solvent extraction-precipitation process. The preferred form of this process comprises a first solvent extraction with depa-topo followed by reductive stripping of the extractant with fe++ - containing phosphoric acid. After reoxidation, the uranium-containing aqueous stripping solution is extracted again with depa-topo and the pregnant organic is then stripped with a dilute ammonium carbonate solution. The resulting ammonium uranyl tricarbonate solution is then acidified, with special kerosene treatment to prevent wax formation, and the acidified solution is reacted with H2O2 to precipitate a uranyl peroxide compound

  4. Experimental Efficiency investigation on heat recovery system used in a solar-powered desalination process

    OpenAIRE

    Rachdi, Aouatef; Qoaider, Louy; Ben-Amara, Mahmoud; Guizani, Amenallah

    2012-01-01

    The aim of this work is to experimentally study, the effect of the heat recovery on water production in a solar desalination process that is working with multiple stage humidification technique. The water production, the temperature and the humidity were tested for such a pilot plant, which operates without and with a heat recovery system. The humidifier efficiency increases with the number of the operating heat exchangers and cannot normally exceed 45% when the system operates wi...

  5. Experimental Study of Displacement Mechanisms in Microbial Improved Oil Recovery Processes

    OpenAIRE

    Afrapoli, Mehdi Shabani

    2010-01-01

    The Microbial Improved Oil Recovery (MIOR) project has been defined at the Norwegian University of Science and Technology (NTNU). It is a cooperative project between the Department of Petroleum Engineering and Applied Geophysics and the Department of Biotechnology both at NTNU.The project involves experimental investigations of the MIOR process. The bacterium Rhodococcus sp.094, extensively studied at NTNU, is used to test its effect on oil recovery. The growth of bacteria is evaluated in san...

  6. Temperature model for process impact non-uniformity in genipin recovery by high pressure processing.

    Science.gov (United States)

    Ramos-de-la-Peña, Ana Mayela; Montañez, Julio C; Reyes-Vega, María de la Luz; Contreras-Esquivel, Juan Carlos

    2015-11-15

    A model for the process impact temperature non-uniformity during high pressure processing (HPP) of genipap fruit purees was found during genipin recovery. Purees were subjected to HPP (130-530 MPa) under quasi-isobaric non-isothermal conditions (15 min; 0, 4.6 and 9.3mg pectinases/g fruit). Genipin and protein concentration was determined, and pH was measured. Polygalacturonase activity was quantified indirectly by protein content (mg/g fruit). First order kinetics described temperature changes (0-4 min). Polygalacturonase was activated at 130 MPa, inactivated reversibly at 330 MPa and activated again at 530 MPa. Enzyme reaction rate constant (k) was placed in the 0-4 min model and temperature from 2 to 15 min was described. Protein content and pH characterization in terms of decimal reduction time improved highly the 2-15 min model. Since temperature changes were modeled, more insight of its behavior in an HPP reactor was obtained, avoiding uniformity assumptions, making easier the industrial scale HPP implementation. PMID:25977049

  7. Aqueous recovery of plutonium from pyrochemical processing residues

    International Nuclear Information System (INIS)

    Pyrochemical processes provide rapid methods to reclaim plutonium from scrap residues. Frequently, however, these processes yield an impure plutonium product and waste residues that are contaminated with actinides and are therefore nondiscardable. The Savannah River Laboratory and Plant and the Rocky Flats Plant are jointly developing new processes using both pyrochemistry and aqueous chemistry to generate pure product and discardable waste. An example of residue being treated is that from the molten salt extraction (MSE), a mixture of NaCl, KCl, MgCl2, PuCl3, AmCl3, PuO2, and Pu0. This mixture is scrubbed with molten aluminum containing a small amount of magnesium to produce a nonhomogeneous Al-Pu-Am-Mg alloy. This process, which rejects most of the NaCl-KCl-MgCl2 salts, results in a product easily dissolved in 6M HNO3 -0.1M HF. Any residual chloride in the product is removed by precipitation with Hg(I) followed by centrifuging. Plutonium and americium are then separated by the standard Purex process. The americium, initially diverted to the solvent extraction waste stream, can either be recovered or sent to waste

  8. Membrane separation processes for argon plasma gas recovery

    OpenAIRE

    Harlacher, Thomas

    2014-01-01

    A mixture of argon and hydrogen is used as plasma gas in a thermal plasma synthesis for the production of silicon carbide. Next to argon and hydrogen, the exhaust gas of the ceramic synthesis contains carbon monoxide. Since argon is an expensive gas, the plasma gas needs to be recycled. For this purpose, the carbon monoxide has to be removed from the exhaust gas. The applicability of a membrane based gas separation process for this separation task was investigated in this study. A process rou...

  9. Separation and recovery of molybdenum values from uranium process waste

    International Nuclear Information System (INIS)

    A method is described of recovering molybdenum and uranium values from a process waste generated from the production of nuclear-grade uranium hexafluoride which consists of: (a) hydrolysing the process waste which contains UF6, MoF6 and MoOF4 in an aqueous solution containing ammonium carbonate and ammonium hydroxide thereby forming ammonium uranyl carbonate; (b) digesting while maintaining a pH > 9, the resulting mother liquor at a temperature of about 600-800C. to evolve CO2 and convert the ammonium uranyl carbonate to solid ammonium diuranate; (c) filtering, washing and drying the solid ammonium diuranate

  10. Determination of sulfur and nitrogen compounds during the processing of dry fermented sausages and their relation to amino acid generation.

    Science.gov (United States)

    Corral, Sara; Leitner, Erich; Siegmund, Barbara; Flores, Mónica

    2016-01-01

    The identification of odor-active sulfur and nitrogen compounds formed during the processing of dry fermented sausages was the objective of this study. In order to elucidate their possible origin, free amino acids (FAAs) were also determined. The volatile compounds present in the dry sausages were extracted using solvent assisted flavor evaporation (SAFE) and monitored by one and two-dimensional gas chromatography with different detectors: mass spectrometry (MS), nitrogen phosphorous (NPD), flame photometric (FPD) detectors, as well as gas chromatography-olfactometry. A total of seventeen sulfur and nitrogen compounds were identified and quantified. Among them, 2-acetyl-1-pyrroline was the most potent odor active compound, followed by methional, ethylpyrazine and 2,3-dihydrothiophene characterized by toasted, cooked potato, and nutty notes. The degradation of FAAs, generated during processing, was related to the production of aroma compounds, such as methionine forming methional and benzothiazole while ornithine was the precursor compound for 2-acetyl-1-pyrroline and glycine for ethylpyrazine. PMID:26213023

  11. A microencapsulation process of liquid mercury by sulfur polymer stabilization/solidification technology. Part II: Durability of materials

    International Nuclear Information System (INIS)

    Under the European LIFE Program a microencapsulation process was developed for liquid mercury using Sulfur Polymer Stabilization/Solidification (SPSS) technology, obtaining a stable concrete-like sulfur matrix that allows the immobilization of mercury for long-term storage. The process description and characterization of the materials obtained were detailed in Part I. The present document, Part II, reports the results of different tests carried out to determine the durability of Hg-S concrete samples with very high mercury content (up to 30 % w/w). Different UNE and RILEM standard test methods were applied, such as capillary water absorption, low pressure water permeability, alkali/acid resistance, salt mist aging, freeze-thaw resistance and fire performance. The samples exhibited no capillarity and their resistance in both alkaline and acid media was very high. They also showed good resistance to very aggressive environments such as spray salt mist, freeze-thaw and dry-wet. The fire hazard of samples at low heat output was negligible. (Author)

  12. A microencapsulation process of liquid mercury by sulfur polymer stabilization/solidification technology. Part II: Durability of materials

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Delgado, A.; Guerrero, A.; Lopez, F. A.; Perez, C.; Alguacil, F. J.

    2012-11-01

    Under the European LIFE Program a microencapsulation process was developed for liquid mercury using Sulfur Polymer Stabilization/Solidification (SPSS) technology, obtaining a stable concrete-like sulfur matrix that allows the immobilization of mercury for long-term storage. The process description and characterization of the materials obtained were detailed in Part I. The present document, Part II, reports the results of different tests carried out to determine the durability of Hg-S concrete samples with very high mercury content (up to 30 % w/w). Different UNE and RILEM standard test methods were applied, such as capillary water absorption, low pressure water permeability, alkali/acid resistance, salt mist aging, freeze-thaw resistance and fire performance. The samples exhibited no capillarity and their resistance in both alkaline and acid media was very high. They also showed good resistance to very aggressive environments such as spray salt mist, freeze-thaw and dry-wet. The fire hazard of samples at low heat output was negligible. (Author)

  13. Exergy driven process synthesis for isoflavone recovery from okara

    NARCIS (Netherlands)

    Jankowiak, L.; Jonkman, J.; Rossier-Miranda, F.; Goot, van der A.J.; Boom, R.M.

    2014-01-01

    Isoflavones, found in soybeans and other members of the fabaceae family, are considered bioactive components of high economic value. An opportunity would be to separate isoflavones from okara, the by-product of the soymilk and tofu production. Such a process would not only valorise that side-stream

  14. Process Mediation, Execution Monitoring and Recovery for Semantic Web Services

    Czech Academy of Sciences Publication Activity Database

    Sycara, K.; Vaculín, Roman

    2008-01-01

    Roč. 31, č. 3 (2008), s. 14-18. ISSN N R&D Projects: GA ČR(CZ) GD201/05/H014; GA MŠk ME08095 Institutional research plan: CEZ:AV0Z10300504 Keywords : process mediation of semantic web services * semantic web services * OWL-S Subject RIV: IN - Informatics, Computer Science

  15. Economic feasibility of biochemical processes for the upgrading of crudes and the removal of sulfur, nitrogen, and trace metals from crude oil -- Benchmark cost establishment of biochemical processes on the basis of conventional downstream technologies. Final report FY95

    Energy Technology Data Exchange (ETDEWEB)

    Premuzic, E.T.

    1996-08-01

    During the past several years, a considerable amount of work has been carried out showing that microbially enhanced oil recovery (MEOR) is promising and the resulting biotechnology may be deliverable. At Brookhaven National Laboratory (BNL), systematic studies have been conducted which dealt with the effects of thermophilic and thermoadapted bacteria on the chemical and physical properties of selected types of crude oils at elevated temperatures and pressures. Current studies indicate that during the biotreatment several chemical and physical properties of crude oils are affected. The oils are (1) emulsified; (2) acidified; (3) there is a qualitative and quantitative change in light and heavy fractions of the crudes; (4) there are chemical changes in fractions containing sulfur compounds; (5) there is an apparent reduction in the concentration of trace metals; and (6) the qualitative and quantitative changes appear to be microbial species dependent; and (7) there is a distinction between biodegraded and biotreated oils. The downstream biotechnological crude oil processing research performed thus far is of laboratory scale and has focused on demonstrating the technical feasibility of downstream processing with different types of biocatalysts under a variety of processing conditions. Quantitative economic analysis is the topic of the present project which investigates the economic feasibility of the various biochemical downstream processes which hold promise in upgrading of heavy crudes, such as those found in California, e.g., Monterey-type, Midway Sunset, Honda crudes, and others.

  16. The chemical processing of gas-phase carbonyl compounds by sulfuric acid aerosols: 2,4-pentanedione

    Science.gov (United States)

    Nozière, Barbara; Riemer, Daniel D.

    This work investigates the interactions between gas-phase carbonyl compounds and sulfuric acid aerosols. It focuses on understanding the chemical processes, giving a first estimate of their importance in the atmosphere, and suggesting directions for further investigations. The solubility and reactivity of a compound with a large enolization constant, 2,4-pentanedione, in water/sulfuric acid solutions 0-96 wt% have been investigated at room temperature using the bubble column/GC-FID technique. 2,4-pentanedione was found to undergo aldol condensation at acidities as low as 20 wt% H 2SO 4, that is, well in the tropospheric range of aerosol composition. In agreement with well-established organic chemical knowledge, this reaction resulted in changes of color of the solutions of potential importance for the optical properties of the aerosols. 2,4-pentanedione was also found to undergo retroaldol reaction, specific to dicarbonyl compounds, producing acetone and acetaldehyde. The Henry's law coefficient for 2,4-pentanedione was found to be a factor 5 larger than the one of acetone over the whole range of acidity, with a value in water of H (297 K)=(155±27) M atm -1. A chemical system is proposed to describe the transformations of carbonyl compounds in sulfuric acid aerosols. Aldol condensation is likely to be the most common reaction for these compounds, probably involving a large number of the ones present in the atmosphere and a wide range of aerosol compositions. The enolization constant contributes as a proportional factor to the rate constant for aldol condensation, and is shown in this work to contribute as an additive constant to the Henry's law coefficient. In addition to the many important aspects of these reactions illustrated in this work, the rate of aldol condensation was estimated to be potentially fast enough for the losses of some compounds in acidic aerosols to compete with their gas-phase chemistry in the atmosphere.

  17. A combined cesium-strontium extraction/recovery process

    International Nuclear Information System (INIS)

    A new solvent extraction process for the simultaneous extraction of cesium and strontium from acidic nitrate media is described. This process uses a solvent formulation comprised of 0.05 M di-t-butylcyclohexano-18-crown-6 (DtBuCH18C6), 0.1 M Crown 100' (a proprietary, cesium-selective derivative of dibenzo-18-crown-6), 1.2 M tributyl phosphate (TBP), and 5% (v/v) lauryl nitrile in an isoparaffinic hydrocarbon diluent. Distribution ratios for cesium and strontium from 4 M nitric acid are 4.13 and 3.46, respectively. A benchtop batch countercurrent extraction experiment indicates that >98% of the cesium and strontium initially present in the feed solution can be removed in only four extraction stages. Through proper choice of extraction and strip conditions, extracted cesium and strontium can be recovered either together or individually

  18. Processing ix spent resin waste for C-14 isotope recovery

    International Nuclear Information System (INIS)

    A process developed at Ontario Hydro for recovering carbon-14 (C-14) from spent ion exchange resin wastes is described. Carbon-14 is an undesirable by-product of CANDU1 nuclear reactor operation. It has an extremely long (5730 years) half-life and can cause dosage to inhabitants by contact, inhalation, or through the food cycle via photosynthesis. Release of carbon-14 to the environment must be minimized. Presently, all the C-14 produced in the Moderator and Primary Heat Transport (PHT) systems of the reactor is effectively removed by the respective ion exchange columns, and the spent ion exchange resins are stored in suitably engineered concrete structures. Because of the large volumes of spent resin waste generated each year this method of disposal by long term storage tends to be uneconomical; and may also be unsatisfactory considering the long half-life of the C-14. However, purified C-14 is a valuable commercial product for medical, pharmaceutical, agricultural, and organic chemistry research. Currently, commercial C-14 is made artificially in research reactors by irradiating aluminum nitride targets for 4.5 years. If the C-14 containing resin waste can be used to reduce this unnecessary production of C-14, the total global build-up of this radioactive chemical can be reduced. There is much incentive in removing the C-14 from the resin waste to reduce the volume of C-14 waste, and also in purifying the recovered C-14 to supply the commercial market. The process developed by Ontario Hydro consists of three main steps: C-14 removal from spent resins, enrichment of recovered C-14, and preparation of final product. Components of the process have been successfully tested at Ontario Hydro's Research Division, but the integration of the process is yet to be demonstrated. A pilot scale plant capable of processing 4 m3 of spent resins annually is being planned for demonstrating the technology. The measured C-14 activity levels on the spent resins ranged from 47-213 Ci

  19. Determination of Cu recovery degree from slags in shaft process by means of radiotracers

    International Nuclear Information System (INIS)

    A radiotracer method has been used for determining the recovery degree of copper from slags after converter and flash furnace processing. Re-processing of slags was carried out in a commercial shaft furnace. The tracer used was 64Cu in forms of pure metal, sulphide or oxide. The method applied has been described and the results of experiments presented. (author)

  20. FBC desulfurization process using coal with low sulfur content, high oxidizing conditions and metamorphic limestones

    Directory of Open Access Journals (Sweden)

    S. R. Bragança

    2009-06-01

    Full Text Available A metamorphic limestone and a dolomite were employed as SO2 sorbents in the desulfurization of gas from coal combustion. The tests were performed in a fluidized bed reactor on a bench and pilot scale. Several parameters such as bed temperature, sorbent type, and sorbent particle size at different Ca/S molar ratios were analyzed. These parameters were evaluated for the combustion of coal with low-sulfur/high-ash content, experimental conditions of high air excess and high O2 level in fluidization air. Under these conditions, typical of furnaces, few published data can be found. In this work, a medium level of desulfurization efficiency (~60% for Ca/S = 2 was obtained.

  1. Dung beetle communities in coal mining areas in the process of recovery

    Directory of Open Access Journals (Sweden)

    Joana Zamprônio Bett

    2014-09-01

    Full Text Available Dung beetles that are sensitive to environmental alterations may be used as indicator species to mark the recovery of degraded areas. This work aimed at registering and comparing the communities of Scarabaeinae located in areas with different periods of environmental recovery after being used for coal mining. This study was developed in Lauro Müller, Santa Catarina, and consisted of two areas in the process of recovery, one for one year and one for five years. Fifteen pitfall traps baited with human feces were placed in each area in order to attract the dung beetles. The counting, identification and measurement of body size and biomass of the specimens captured were carried out in the laboratory. Sampling sufficiency was verified and variables from both areas were compared using a t test. The recorded species were Canthon aff. chalybaeus, Canthon angularis, Canthon rutilans cyanescens, Deltochilum multicolor, Dichotomius sericeus, Eurysternus parallelus and Ontherus sulcator. A total of 35 individuals were captured, three in the one-year recovery area and 32 in the area under recovery for five years, C. rutilans cyanescens being the most abundant species (40.6%. All species collected were found in the five-years recovery area, whereas only C. aff. chalybaeus and D. multicolor were found in the one-year recovery area. Individuals sampled in the area with one year of recovery had an average size of 11.03 mm and average biomass of 0.051 g, whereas in the five-years recovery area the average size and the biomass of the dung beetles sampled was 12.25 mm and 0.093 g, respectively.

  2. Environmental aspects of heavy oil recovery by thermal EOR processes

    International Nuclear Information System (INIS)

    Production of heavy oil resources by thermal techniques is greatly impacted by environmental regulations. Environmental laws affecting oil production by thermal techniques are administered by federal, state, and local agencies. Frequently, jurisdictions overlap and duplicate reporting actions are required. While the environmental specialist within a company may be familiar with the regulations, others may not. The technical and operating personnel responsible for reporting actions must also be aware of the essence of these regulations, so that inadvertent noncompliance with applicable environmental rules can be avoided. It is the purpose of this paper to familiarize practicing engineers and other interested personnel with applicable environmental rules and regulations. The various environmental rules, standards or criteria enacted or enforced by federal, state, and/or local governments are summarized and their impact on thermal processes assessed. Since California's environmental standards are considerably more stringent than those required by federal regulations, major emphasis is placed on detailing the state regulations. Further, the potential environmental deterioration likely to be generated by thermal EOR techniques and the nature or type of pollutants to be discharged during their application have been examined. The regulations pertaining to air and water quality and their relevance to thermal EOR processes are briefly discussed

  3. Biological conversion of hydrogen sulfide into elemental sulfur

    Energy Technology Data Exchange (ETDEWEB)

    Basu, R.; Clausen, E.C.; Gaddy, J.L. [Bioengineering Resources, Inc., Fayetteville, AR (United States)

    1996-12-31

    Currently, hydrogen sulfide is removed from process gas streams by a series of reactions at high temperature to produce elemental sulfur in Claus, Stretford or other processes. These physicochemical processes have high intrinsic capital and operating costs, often are restricted by contaminants, and do not effectively remove all the H{sub 2}S. As an alternative, the anaerobic, photosynthetic bacterium, Chlorobium thiosulfatophilum, has been demonstrated to convert hydrogen sulfide to elemental sulfur in a single step at atmospheric conditions. The autotrophic bacterium uses CO{sub 2} as the carbon source. Energy for cell metabolism is provided by incandescent light and the oxidation of H{sub 2}S. A bench scale study has been performed in a CSTR equipped with a sulfur separator. Optimum process conditions have been achieved to maximize cell growth and elemental sulfur production. Near total conversion of H{sub 2}S is achieved in a retention time of a few minutes. High concentrations of H{sub 2}S or organics do not affect the culture. Sulfur recovery by settling is very efficient and near theoretical yields of sulfur are achieved. Economic projections indicate that sour gas can be desulfurized for $0.08-0.12/MSCF. 13 refs.

  4. Application of exergy analysis for improving energy efficiency of natural gas liquids recovery processes

    International Nuclear Information System (INIS)

    Thermodynamic analysis and optimization method is applied to provide design guidelines for improving energy efficiency and cost-effectiveness of natural gas liquids recovery processes. Exergy analysis is adopted in this study as a thermodynamic tool to evaluate the loss of exergy associated with irreversibility in natural gas liquids recovery processes, with which conceptual understanding on inefficient design feature or equipment can be obtained. Natural gas liquids processes are modeled and simulated within UniSim® simulator, with which detailed thermodynamic information are obtained for calculating exergy loss. The optimization framework is developed by minimizing overall exergy loss, as an objective function, subject to product specifications and engineering constraints. The optimization is carried out within MATLAB® with the aid of a stochastic solver based on genetic algorithms. The process simulator is linked and interacted with the optimization solver, in which optimal operating conditions can be determined. A case study is presented to illustrate the benefit of using exergy analysis for the design and optimization of natural gas liquids processes and to demonstrate the applicability of design method proposed in this paper. - Highlights: • Application of exergy analysis for natural gas liquids (NGL) recovery processes. • Minimization of exergy loss for improving energy efficiency. • A systematic optimization framework for the design of NGL recovery processes

  5. Calcium looping process for high purity hydrogen production integrated with capture of carbon dioxide, sulfur and halides

    Energy Technology Data Exchange (ETDEWEB)

    Ramkumar, Shwetha; Fan, Liang-Shih

    2015-11-04

    A process for producing hydrogen comprising the steps of: (i) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam, sulfur and halide contaminants in the form of H.sub.2S, COS, and HX, wherein X is a halide; (ii) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO.sub.2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO.sub.3, CaS and CaX.sub.2; (iii) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (iv) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO.sub.2, in the presence of synthesis gas, in the presence of H.sub.2 and O.sub.2, under partial vacuum, and combinations thereof.

  6. Experimental study on the Bunsen reaction using an ionic liquid in thermochemical iodine-sulfur process for hydrogen production

    International Nuclear Information System (INIS)

    The feasibility of the Bunsen reaction using an ionic liquid (IL) containing iodide ions as the solvent was experimentally examined to improve the thermal efficiency of a thermochemical water-splitting iodine-sulfur (IS) process for hydrogen production using a high-temperature gas-cooled reactor (HTGR) by increasing the hydrogen iodide (HI) concentration in the Bunsen reaction. The solubility of the reactants of the Bunsen reaction, iodine (I2) and sulfur dioxide (SO2), in the IL was measured to confirm the feasibility of the reaction. 1-Butyl-3-methylimidazolium iodide ([bimi][I]) showed an I2 solubility of 4.78 mol/mol at room temperature, which was 2.47 times higher than that in hydriodic acid. [bimi][I] also showed a high SO2 solubility of 3.42 mol/mol, which was 125 times higher than that in water. The feasibility of the Bunsen reaction using the IL was confirmed in terms of the increases in I2 and SO2 concentrations in the Bunsen reaction. The HI concentration in the hydriodic acid in the Bunsen reaction using [bimi][I] was preliminary examined at room temperature, ambient pressure, and reactant composition of IL:I2:SO2:H2O=0.25-0.5:0.51-2.1:1.0:1.0 (molar ratio). The maximum HI concentration was 24.5 mol% (=69.8 wt%), which was higher than that obtained by the conventional Bunsen reaction. (author)

  7. Development of novel processes for Cu concentrates without producing sulfuric acid; Hiryusan hasseigata no atarashii doshigen shori gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T.; Noguchi, F.; Takasu, T.; Ito, H. [Kyushu Inst. of Technology, Kitakyushu (Japan). Faculty of Engineering

    1997-02-01

    In the refining process for the production of copper from pyrites, heat treatment is carried out in a neutral atmosphere so that part of the sulphur will be collected in the form of simple sulfur and that pyrites naturally low in reactivity will be made active. A basic study is also conducted of a very high speed electrolytic method. The chemical aspects of pyrites which are various in composition (mainly CuFeS2) are clarified by X-ray diffraction, and then is subjected to heat-treatment in a 773K-1073K argon atmosphere. There is a decrease in the amount of sulfur at a temperatures not lower than 973K. The X-ray main diffraction line splits for the emergence of some lower angle diffraction lines. The specimen is then subjected to a leach test in a copper chloride base liquor, to disclose that leachability grows remarkably higher in the presence of a great change in the X-ray diffraction lattice constant. An experiment follows in which an electrolyte is allowed to flow at a high speed for accelerating the rate of electrolytic refining in an effort to prevent the passivation of anode and deposition of dendrite on the cathode that is apt to occur when the current density is high. Passivation is prevented when the flow rate is 10m/min or higher in the vicinity of the anode surface for the formation of a smooth electrodeposited surface. 2 refs., 2 figs., 2 tabs.

  8. Calcium looping process for high purity hydrogen production integrated with capture of carbon dioxide, sulfur and halides

    Science.gov (United States)

    Ramkumar, Shwetha; Fan, Liang-Shih

    2013-07-30

    A process for producing hydrogen comprising the steps of: (i) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam, sulfur and halide contaminants in the form of H.sub.2S, COS, and HX, wherein X is a halide; (ii) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO.sub.2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO.sub.3, CaS and CaX.sub.2; (iii) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (iv) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO.sub.2, in the presence of synthesis gas, in the presence of H.sub.2 and O.sub.2, under partial vacuum, and combinations thereof.

  9. Structural insight into SoxC and SoxD interaction and their role in electron transport process in the novel global sulfur cycle in Paracoccus pantotrophus

    International Nuclear Information System (INIS)

    Microbial oxidation of reduced inorganic sulfur compounds mainly sulfur anions in the environment is one of the major reactions of the global sulfur cycle mediated by phylogenetically diverse prokaryotes. The sulfur oxidizing gene cluster (sox) of α-Proteobacteria comprises of at least 16 genes, which form two transcriptional units, viz., soxSRT and soxVWXYZABCDEFGH. Sequence analysis reveals that soxD gene product (SoxD) belongs to the di-heme cytochrome c family of electron transport proteins whereas soxC gene product (SoxC) is a sulfur dehydrogenase. We employed homology modeling to construct the three-dimensional structures of the SoxC and SoxD from Paracoccus pantotrophus. SoxD protein is known to interact with SoxC. With the help of docking studies we have identified the residues involved in the interaction of SoxC and SoxD. The putative active site geometries of these two proteins as well as the structural basis of the involvements of these proteins in electron transport process during the oxidation of sulfur anions are also investigated

  10. FASTMET(reg. sign): Proven process for steel mill waste recovery

    Energy Technology Data Exchange (ETDEWEB)

    McClelland, J.M. Jr. [Midrex Technologies, Incorporated, Charlotte, NC (United States)

    2002-07-01

    Two FASTMET{trademark} Process steel mill waste recovery plants are now in commercial operation. These FASTMET{trademark} Process facilities are converting steel mill wastes into useable iron units and valuable byproducts. This paper discusses operating experience from both plants, including waste oil fuel operation, product quality, zinc recovery and emissions testing. The first commercial FASTMET Plant was constructed at Nippon Steel's Hirohata Works, the second is now in operation at Kobe Steel's Kakogawa Works in Japan. 22 refs., 11 figs., 12 tabs.

  11. In Situ Analysis of Sulfur Species in Sulfur Globules Produced from Thiosulfate by Thermoanaerobacter sulfurigignens and Thermoanaerobacterium thermosulfurigenes▿ †

    OpenAIRE

    Lee, Yong-Jin; Prange, Alexander; Lichtenberg, Henning; Rohde, Manfred; Dashti, Mona; Wiegel, Juergen

    2007-01-01

    The Firmicutes Thermoanaerobacter sulfurigignens and Thermoanaerobacterium thermosulfurigenes convert thiosulfate, forming sulfur globules inside and outside cells. X-ray absorption near-edge structure analysis revealed that the sulfur consisted mainly of sulfur chains with organic end groups similar to sulfur formed in purple sulfur bacteria, suggesting the possibility that the process of sulfur globule formation by bacteria is an ancient feature.

  12. Recovery of Nutrients from Struvite Crystallization process using Dairy Manure

    Directory of Open Access Journals (Sweden)

    T.SUVATHIKA

    2016-04-01

    Full Text Available Wastes collected from dairy farm are converted into manure by various processes for their application in agricultural fields in order to yield more production of crops. But unexpectedly the nutrient present in the manure is not completely utilized by the plants sometimes due to surface water runoff, floods and certain other aspects. The production of mineral fertilizers has a significant environmental impact, including depletion of fossil fuels and minerals. Therefore, the nutrients present in this manure comprise of minerals such as Magnesium, Ammonium and Phosphate which is otherwise called as struvite. This struvite can be precipitated separately and can be made as a substitute for manure since struvite is far rich in nutrients compared to manure and also it is considered as a slow releasing fertilizer which has less soluble in water. This thesis work shows the amount of MAP (Mg, Nh4, and P nutrients generated when Dairy manure is used as the influent to the fluidized bed reactor with addition of Mgcl which acts as a precipitating agent and also the impact of struvite precipitation in the concentration of total solids, hardness, pH, BOD/COD from the dairy wastewater is observed.

  13. MANAGEMENT OF PROCESSING AND RECOVERY OF LEATHER WASTE

    Directory of Open Access Journals (Sweden)

    STAN Ovidiu Valentin

    2014-05-01

    Full Text Available The leather and leather goods industry development is conditioned by the development of the supply of raw materials - animal husbandry and chemical industries, sectors that tend to develop intensive on vertical - which causes a shortage of raw materials in relation with the market demand for quality products. The leather is the basic raw material of the leather and leather goods industry, this raw material is the most substantial contribution to downstream sectors, giving them a competitive advantage and it is known that the leather has the greatest potential to add value to the products in which it is incorporated. The advantages of using leather are many, the most important qualities are its hygienic properties, flexibility and adaptability to a wide variety of applications. Leather is manufactured on demand for each type of application, such as shoes, clothes, gloves, handbags, furniture upholstery or car interiors, yachts and planes. It requires better use of raw materials by using new technologies and manufacturing processes based on non-invasive methods on the environment leading to increase the product life cycle. The leather and leather goods industry is a supplier of large amounts of waste from the production cycle, waste that has the same properties and qualities as raw material used in the base product. Leather waste represents a loss for the companies, an additional cost related to storage and environmental protection.

  14. Supporting technology for enhanced oil recovery: Sixth amendment and extension to Annex IV enhanced oil recovery thermal processes

    Energy Technology Data Exchange (ETDEWEB)

    Reid, T.B. (USDOE Bartlesville Project Office, OK (United States)); Rivas, O. (INTEVEP, Filial de Petroleos de Venezuela, SA, Caracas (Venezuela))

    1991-10-01

    This report contains the results of efforts under the six tasks of the Sixth Amendment and Extension of Annex 4, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections (for each of the 6 tasks) and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section. The tasks are numbered 44 through 49. Tasks are: DOE-SUPRI-laboratory research on steam foam, CAT-SCAN, and in-situ combustion; INTEVEP-laboratory research and field projects on steam foam; DOE-NIPER-laboratory research and field projects light oil steam flooding; INTEVEP-laboratory research and field studies on wellbore heat losses; DOE-LLNL-laboratory research and field projects on electromagnetic induction tomography; INTEVEP-laoboratory research on mechanistic studies.

  15. Enhancement of the photo conversion efficiencies in Cu(In,Ga)(Se,S)2 solar cells fabricated by two-step sulfurization process

    International Nuclear Information System (INIS)

    Cu(In,Ga)(Se,S)2 (CIGSS) absorber layers were fabricated by using a modified two-stage sputter and a sequential selenization/sulfurization method, and the sulfurization process is changed from one-step to two-step. The two-step sulfurization was controlled with two different H2S gas concentrations during the sulfurization treatment. This two-step process yielded remarkable improvements in the efficiency (+0.7%), open circuit voltage (+14 mV), short circuit current (+0.23 mA/cm2), and fill factor (+0.21%) of a CIGSS device with 30 × 30 cm2 in size, owing to the good passivation at the grain boundary surface, uniform material composition among the grain boundaries, and modified depth profile of Ga and S. The deterioration of the P/N junction quality was prevented by the optimized S content in the CIGSS absorber layer. The effects of the passivation quality at the grain boundary surface, the material uniformity, the compositional depth profiles, the microstructure, and the electrical characteristics were examined by Kelvin probe force microscopy, X-ray diffraction, secondary ion mass spectrometry, scanning electron microscopy, and current-voltage curves, respectively. The two-step sulfurization process is experimentally found to be useful for obtaining good surface conditions and, enhancing the efficiency, for the mass production of large CIGSS modules

  16. Enhancement of the photo conversion efficiencies in Cu(In,Ga)(Se,S){sub 2} solar cells fabricated by two-step sulfurization process

    Energy Technology Data Exchange (ETDEWEB)

    Yang, JungYup; Nam, Junggyu; Kim, Dongseop; Lee, Dongho, E-mail: dhlee0333@gmail.com, E-mail: ddang@korea.ac.kr [Photovoltaic Development Team, Energy Storage Business Division, Samsung SDI, Cheonan-si 331-300 (Korea, Republic of); Kim, GeeYeong; Jo, William [Department of Physics and New and Renewable Energy Research Center, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Kang, Yoonmook, E-mail: dhlee0333@gmail.com, E-mail: ddang@korea.ac.kr [KUKIST Green School, Graduate School of Energy and Environment, Korea University, Seoul 136-701 (Korea, Republic of)

    2015-11-09

    Cu(In,Ga)(Se,S){sub 2} (CIGSS) absorber layers were fabricated by using a modified two-stage sputter and a sequential selenization/sulfurization method, and the sulfurization process is changed from one-step to two-step. The two-step sulfurization was controlled with two different H{sub 2}S gas concentrations during the sulfurization treatment. This two-step process yielded remarkable improvements in the efficiency (+0.7%), open circuit voltage (+14 mV), short circuit current (+0.23 mA/cm{sup 2}), and fill factor (+0.21%) of a CIGSS device with 30 × 30 cm{sup 2} in size, owing to the good passivation at the grain boundary surface, uniform material composition among the grain boundaries, and modified depth profile of Ga and S. The deterioration of the P/N junction quality was prevented by the optimized S content in the CIGSS absorber layer. The effects of the passivation quality at the grain boundary surface, the material uniformity, the compositional depth profiles, the microstructure, and the electrical characteristics were examined by Kelvin probe force microscopy, X-ray diffraction, secondary ion mass spectrometry, scanning electron microscopy, and current-voltage curves, respectively. The two-step sulfurization process is experimentally found to be useful for obtaining good surface conditions and, enhancing the efficiency, for the mass production of large CIGSS modules.

  17. Enhancement of the photo conversion efficiencies in Cu(In,Ga)(Se,S)2 solar cells fabricated by two-step sulfurization process

    Science.gov (United States)

    Yang, JungYup; Nam, Junggyu; Kim, Dongseop; Kim, GeeYeong; Jo, William; Kang, Yoonmook; Lee, Dongho

    2015-11-01

    Cu(In,Ga)(Se,S)2 (CIGSS) absorber layers were fabricated by using a modified two-stage sputter and a sequential selenization/sulfurization method, and the sulfurization process is changed from one-step to two-step. The two-step sulfurization was controlled with two different H2S gas concentrations during the sulfurization treatment. This two-step process yielded remarkable improvements in the efficiency (+0.7%), open circuit voltage (+14 mV), short circuit current (+0.23 mA/cm2), and fill factor (+0.21%) of a CIGSS device with 30 × 30 cm2 in size, owing to the good passivation at the grain boundary surface, uniform material composition among the grain boundaries, and modified depth profile of Ga and S. The deterioration of the P/N junction quality was prevented by the optimized S content in the CIGSS absorber layer. The effects of the passivation quality at the grain boundary surface, the material uniformity, the compositional depth profiles, the microstructure, and the electrical characteristics were examined by Kelvin probe force microscopy, X-ray diffraction, secondary ion mass spectrometry, scanning electron microscopy, and current-voltage curves, respectively. The two-step sulfurization process is experimentally found to be useful for obtaining good surface conditions and, enhancing the efficiency, for the mass production of large CIGSS modules.

  18. Structural development and dynamic process in sulfurizing precursors to prepare Cu{sub 2}ZnSnS{sub 4} absorber layer

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Donghua, E-mail: donghua_fan@126.com [School of Applied Physics and Materials, Wuyi University, 22 Dongcheng Village, Jiangmen 529020 (China); Zhang, Rong [Department of Physics, Shanghai Maritime University, 1550 Haigang Avenue, Shanghai 201306 (China); Zhu, Yufu [Faculty of Mechanical Engineering, Huaiyin Institute of Technology, Huaian 223003 (China); Peng, Huiren; Zhang, Junzhi [School of Applied Physics and Materials, Wuyi University, 22 Dongcheng Village, Jiangmen 529020 (China)

    2014-01-15

    Highlights: • CZTS films were fabricated by sulfurizing the fabricated precursor films. • Annealing time and temperature are very important for synthesis of pure CZTS films. • Pure CZTS films with high quality can prepared at 500 °C and 90 min. • Both high temperature and long heating time causes the decomposition of CZTS films. -- Abstract: Cu{sub 2}ZnSnS{sub 4} (CZTS) films were fabricated by sulfurizing the fabricated metal-precursor films under sulfur atmosphere. All samples prepared at different conditions were characterized by X-ray diffraction, Raman scattering measurements, scanning electron microscopy, energy dispersive X-ray spectroscopy, and UV spectrophotometer. We systematically studied the influence of sulfurization time and temperature on structures, morphologies, compositions, and optical properties, and analyzed deeply the transformation of structural phase and dynamic process during the formation process of CZTS films. Experimental results indicate that the proper sulfurization time and temperature play an important role in synthesizing pure CZTS films with high quality. Compared with the others, the prepared sample at 500 °C and 90 min shows uniform surface morphology, excellent crystal quality, and optical properties. Various growth conditions realize the modulation of structure, impurity phase, morphology and optical properties. The present research results are helpful for us to deeply understand the growth process of CZTS film and pave the way for realizing the fabrication of high quality CZTS absorption layer.

  19. Recovery of volatile products from dilute high-fouling process streams.

    Science.gov (United States)

    Madson, P W; Lococo, D B

    2000-01-01

    As biomass hydrolysis and fermentation technologies approach commercial viability, advancements in product recovery technologies will be required. For cases in which fermentation products are more volatile than water, recovery by distillation is often the technology of choice. Distillation technologies that will allow the economic recovery of dilute volatile products from streams containing a variety of impurities have been developed and commercially demonstrated. Distillation tower and tray designs, along with specialized heat-exchanger designs, allowing for extended processing intervals on solutions containing lignocellulosic residues, organic acids, and inorganic salts concentrations > 100 g/L are in commercial operation. In the case of ethanol, distillation energy consumption efficiencies for processing solutions containing 120 g/L. These proprietary technologies have been applied individually at commercial scale, and designs have been developed that incorporate the combined technologies with only a marginal increase in capital investment compared to traditional methods. PMID:10849857

  20. Processing and damage recovery of intrinsic self-healing glass fiber reinforced composites

    Science.gov (United States)

    Sordo, Federica; Michaud, Véronique

    2016-08-01

    Glass fiber reinforced composites with a self-healing, supramolecular hybrid network matrix were produced using a modified vacuum assisted resin infusion moulding process adapted to high temperature processing. The quality and fiber volume fraction (50%) of the obtained materials were assessed through microscopy and matrix burn-off methods. The thermo-mechanical properties were quantified by means of dynamic mechanical analysis, revealing very high damping properties compared to traditional epoxy-based glass fiber reinforced composites. Self-healing properties were assessed by three-point bending tests. A high recovery of the flexural properties, around 72% for the elastic modulus and 65% of the maximum flexural stress, was achieved after a resting period of 24 h at room temperature. Recovery after low velocity impact events was also visually observed. Applications for this intrinsic and autonomic self-healing highly reinforced composite material point towards semi-structural applications where high damping and/or integrity recovery after impact are required.

  1. Simultaneous bioreduction of nitrate and chromate using sulfur-based mixotrophic denitrification process

    International Nuclear Information System (INIS)

    Highlights: • Simultaneous heterotrophic and autotrophic denitrification was stimulated. • Simultaneous bioreduction of nitrate and chromate was achieved. • Total chromium decreased 3−–N and Cr(VI) concentrations of 75 mg/L and 10 mg/L, respectively, and 3.7 h HRT. Maximum denitrification rate was 0.5 g NO3−–N/(L.d) when the bioreactor was fed with 75 mg/L NO3−–N, 150 mg/L methanol and 10 mg/L Cr(VI). The share of autotrophic denitrification was between 12% and 50% depending on HRT, C/N ratio and Cr(VI) concentration. Effluent total chromium was below 50 μg/L provided that influent Cr(VI) concentration was equal or below 5 mg/L. DGGE results showed stable microbial community throughout the operation and the presence of sulfur oxidizing denitrifying bacteria (Thiobacillus denitrificans) and Cr(VI) reducing bacteria (Exiguobacterium spp.) in the column bed

  2. Activity Enhancement of Vanadium Catalysts with Ultrasonic Preparation Process for the Oxidation of Sulfur Dioxide

    Institute of Scientific and Technical Information of China (English)

    Zhenxing Chen; Honggui Li; Lingsen Wang

    2003-01-01

    The effect of ultrasonic cavitations on the activity of vanadium catalysts at low temperatures for the oxidation of sulfur dioxide, in which refined carbonized mother liquor had been added, was investigated.Twenty minutes were needed to produce obvious cavitations when the catalyst raw material was treated in the 50 W ultrasonic generator. However, only 10 minutes would be needed in a 150 W ultrasonic generator.The higher the temperature of the wet material, the less time was needed to produce cavitations, and the optimal temperature was 60 ℃. The water content in the wet material mainly affected the quantity of cavitations. Ls-8 catalyst was prepared using ultrasonic. Its activity for conversion of SO2 reached to 52.5% at 410 ℃ and 4.2% at 350 ℃. The differential thermal analyses indicate that both endothermic peaks and exothermic peaks noticeably shifted forward compared with Ls catalyst prepared without ultrasonic, and SEM results show a uniform pore size distribution for Ls-8 catalyst.

  3. Process integration in bioprocess indystry: waste heat recovery in yeast and ethyl alcohol plant

    International Nuclear Information System (INIS)

    The process integration of the bioprocess plant for production of yeast and alcohol was studied. Preliminary energy audit of the plant identified the huge amount of thermal losses, caused by waste heat in exhausted process streams, and reviled the great potential for energy efficiency improvement by heat recovery system. Research roadmap, based on process integration approach, is divided on six phases, and the primary tool used for the design of heat recovery network was Pinch Analysis. Performance of preliminary design are obtained by targeting procedure, for three process stream sets, and evaluated by the economic criteria. The results of process integration study are presented in the form of heat exchanger networks which fulfilled the utilization of waste heat and enable considerable savings of energy in short payback period.

  4. Comparison of fixation and processing methods for hairless guinea pig skin following sulfur mustard exposure. (Reannouncement with new availability information)

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, M.A.; Braue Jr, E.H.

    1992-12-31

    Ten anesthetized hairless guinea pigs Crl:IAF(HA)BR were exposed to 10 pi of neat sulfur mustard (HD) in a vapor cup on their skin for 7 min. At 24 h postexposure, the guinea pigs were euthanatized and skin sections taken for histologic evaluation. The skin was fixed using either 10% neutral buffered formalin (NBF), McDowell Trump fixative (4CF-IG), Zenker`s formol-saline (Helly`s fluid), or Zenker`s fluid. Fixed skin sections were cut in half: one half was embedded in paraffin and the other half in plastic (glycol methacrylate). Paraffin-embedded tissue was stained with hematoxylin and eosin; plastic-embedded tissue was stained with Lee`s methylene blue basic fuchsin. Skin was also frozen unfixed, sectioned by cryostat, and stained with pinacyanole. HD-exposed skin was evaluated histologically for the presence of epidermal and follicular necrosis, microblister formation, epidermitis, and intracellular edema to determine the optimal fixation and embedding method for lesion preservation. The percentage of histologic sections with lesions varied little between fixatives and was similar for both paraffin and plastic embedding material. Plastic-embedded sections were thinner, allowing better histologic evaluation, but were more difficult to stain. Plastic embedding material did not infiltrate tissue fixed in Zenker`s fluid or Zenker`s formol-saline. Frozen tissue sections were prepared in the least processing time and lesion preservation was comparable to fixed tissue. It was concluded that standard histologic processing using formalin fixation and paraffin embedding is adequate for routine histopathological evaluation of HD skin lesions in the hairless guinea pig.... Sulfur mustard, Vesicating agents, Pathology, Hairless guinea pig model, Fixation.

  5. Waste processing cost recovery at Los Alamos National Laboratory--analysis and recommendations

    International Nuclear Information System (INIS)

    Los Alamos National Laboratory is implementing full cost recovery for waste processing in fiscal year 2009 (FY2009), after a transition year in FY2008. Waste processing cost recovery has been implemented in various forms across the nuclear weapons complex and in corporate America. The fundamental reasoning of sending accurate price signals to waste generators is economically sound, and leads to waste minimization and reduced waste expense over time. However, Los Alamos faces significant implementation challenges because of its status as a government-owned, contractor-operated national scientific institution with a diverse suite of experimental and environmental cleanup activities, and the fact that this represents a fundamental change in how waste processing is viewed by the institution. This paper describes the issues involved during the transition to cost recovery and the ultimate selection of the business model. Of the six alternative cost recovery models evaluated, the business model chosen to be implemented in FY2009 is Recharge Plus Generators Pay Distributed Direct. Under this model, all generators who produce waste must pay a distributed direct share associated with their specific waste type to use a waste processing capability. This cost share is calculated using the distributed direct method on the fixed cost only, i.e., the fixed cost share is based on each program's forecast proportion of the total Los Alamos volume forecast of each waste type. (Fixed activities are those required to establish the waste processing capability, i.e., to make the process ready, permitted, certified, and prepared to handle the first unit ofwaste. Therefore, the fixed cost ends at the point just before waste begins 'to be processed. The activities to actually process the waste are considered variable.) The volume of waste actually sent for processing is charged a unit cost based solely on the variable cost of disposing of that waste. The total cost recovered each year is the

  6. Waste Processing Cost Recovery at Los Alamos National Laboratory-Analysis and Recommendations

    International Nuclear Information System (INIS)

    Los Alamos National Laboratory is implementing full cost recovery for waste processing in fiscal year 2009 (FY2009), after a transition year in FY2008. Waste processing cost recovery has been implemented in various forms across the nuclear weapons complex and in corporate America. The fundamental reasoning of sending accurate price signals to waste generators is economically sound, and leads to waste minimization and reduced waste expense over time. However, Los Alamos faces significant implementation challenges because of its status as a government-owned, contractor-operated national scientific institution with a diverse suite of experimental and environmental cleanup activities, and the fact that this represents a fundamental change in how waste processing is viewed by the institution. This paper describes the issues involved during the transition to cost recovery and the ultimate selection of the business model. Of the six alternative cost recovery models evaluated, the business model chosen to be implemented in FY2009 is Recharge Plus Generators Pay Distributed Direct. Under this model, all generators who produce waste must pay a distributed direct share associated with their specific waste type to use a waste processing capability. This cost share is calculated using the distributed direct method on the fixed cost only, i.e., the fixed cost share is based on each program's forecast proportion of the total Los Alamos volume forecast of each waste type. (Fixed activities are those required to establish the waste processing capability, i.e., to make the process ready, permitted, certified, and prepared to handle the first unit of waste. Therefore, the fixed cost ends at the point just before waste begins to be processed. The activities to actually process the waste are considered variable.) The volume of waste actually sent for processing is charged a unit cost based solely on the variable cost of disposing of that waste. The total cost recovered each year is the

  7. Preparation of Cu2Sn3S7 Thin-Film Using a Three-Step Bake-Sulfurization-Sintering Process and Film Characterization

    Directory of Open Access Journals (Sweden)

    Tai-Hsiang Lui

    2015-01-01

    Full Text Available Cu2Sn3S7 (CTS can be used as the light absorbing layer for thin-film solar cells due to its good optical properties. In this research, the powder, baking, sulfur, and sintering (PBSS process was used instead of vacuum sputtering or electrochemical preparation to form CTS. During sintering, Cu and Sn powders mixed in stoichiometric ratio were coated to form the thin-film precursor. It was sulfurized in a sulfur atmosphere to form CTS. The CTS film metallurgy mechanism was investigated. After sintering at 500°C, the thin film formed the Cu2Sn3S7 phase and no impurity phase, improving its energy band gap. The interface of CTS film is continuous and the formation of intermetallic compound layer can increase the carrier concentration and mobility. Therefore, PBSS process prepared CTS can potentially be used as a solar cell absorption layer.

  8. Gene recovery microdissection (GRM) a process for producing chromosome region-specific libraries of expressed genes

    Energy Technology Data Exchange (ETDEWEB)

    Christian, A T; Coleman, M A; Tucker, J D

    2001-02-08

    Gene Recovery Microdissection (GRM) is a unique and cost-effective process for producing chromosome region-specific libraries of expressed genes. It accelerates the pace, reduces the cost, and extends the capabilities of functional genomic research, the means by which scientists will put to life-saving, life-enhancing use their knowledge of any plant or animal genome.

  9. Efficient ethanol recovery from fermentation broths with integrated distillation-vapor permeation hybrid process

    Science.gov (United States)

    The energy demand of distillation-molecular sieve systems for ethanol recovery/dehydration can be significant, particularly for dilute solutions. An alternative hybrid process integrating vapor stripping (like a beer still) with vapor compression and a vapor permeation membrane s...

  10. Direct sulfur removal from natural gas with the redox process Sulfint HP; Desulfuration directe du gaz naturel par le procede redox Sulfint HP

    Energy Technology Data Exchange (ETDEWEB)

    Guillon, S.; Le Strat, P.Y. [Gaz de France, GDF, 75 - Paris (France); Ballaguet, J.P.; Streicher, Ch. [Institut Francais du Petrole, IFP, 92 - Rueil Malmaison (France); Cousin, J.P.; Gessat, T. [Le Gaz Integral, 92 - Nanterre (France)

    2000-07-01

    The new redox process Sulfint HP has been developed for removing H{sub 2}S from high pressure gases. Its technical innovation lies in a separate high pressure removal of elemental sulfur particles and a subsequent low pressure oxidation of the catalyst. Only the stoichiometric quantity, needed for H{sub 2}S removal, of clear redox solution is de-pressurized. In 1998, the Sulfint HP process has been tested continuously for two months on a pilot scale utilizing natural gas from an underground storage (gas flow rate: up to 2 000 m3(n)/h [1.7 MMSCFD], pressure: 80 bar [1150 psi]). More than 10{sup 6} m3(n) (850 MMSCF) of gas with 15 ppm H{sub 2}S have been treated to less than 1 ppm as the operation of the pilot was always very smooth. The high pressure sulfur separation is performed by a filter designed for continuous high pressure operation. Filtration cartridges, constituted of flexible filtration clothes, are alternatively loaded and discharged by reverse flow. The settled sulfur cake is periodically removed through a depressurization chamber. During the pilot test, the filter operation has proved to be easy and reliable. In addition no foaming or plugging problems and no troublesome sulfur sediments have been observed. This first two months pilot tests confirmed that high pressure filtration of sulfur loaded redox solution allows to operate the overall Sulfint HP unit without any foaming or plugging problems. (authors)

  11. Genetic control over the processes of postirradiation recovery of a compact chromosome in micrococcus radiodurans

    International Nuclear Information System (INIS)

    X-irradiation of Micrococcus radiodurans cells with sublethal doses caused disturbances in the structure of a membrane-bound compact chromosome. Recovery of the compact chromosome occurred during the postirradiation incubation of the wild type cells and cells of the UVS-17 mutant deficient in DNA-polymerase. This process was blocked in cells of rec-30 mutant with the impaired system of genetic recombination: this is indicative of an important role played by rec-30 gene product in the postirradiation recovery of the compact chromosome in M. radiodurans cells

  12. An assessment of waste processing/resource recovery technologies for lunar/Mars life applications

    Science.gov (United States)

    Verostko, Charles E.; Packham, Nigel J. C.; Henninger, Donald H.

    1992-01-01

    NASA's future manned missions to explore the solar system are by nature of long duration, mandating extensive regeneration of life support consumables from wastes generated in space-based habitats. Long-duration exploration missions would otherwise be prohibitive due to the number and frequency of energy-intensive resupply missions from Earth. Resource recovery is therefore a critical component of the controlled ecological life support system (CELSS). In order to assess resource recovery technologies for CELSS applications, the Crew and Thermal Systems Division at NASA-Johnson Space Center convened a three-day workshop to assess potential resource recovery technologies for application in a space-based CELSS. This paper describes the methodology of assessing and ranking of these technologies. Recommendations and issues are identified. Evaluations focused on the processes for handling and treatment of inedible plant biomass, human waste, and human generated trash. Technologies were assessed on the basis of safety, reliability, technology readiness, and performance characteristics.

  13. Recovery of Flavonoids from Orange Press Liquor by an Integrated Membrane Process

    OpenAIRE

    Alfredo Cassano; Carmela Conidi; René Ruby-Figueroa

    2014-01-01

    Orange press liquor is a by-product generated by the citrus processing industry containing huge amounts of natural phenolic compounds with recognized antioxidant activity. In this work, an integrated membrane process for the recovery of flavonoids from orange press liquors was investigated on a laboratory scale. The liquor was previously clarified by ultrafiltration (UF) in selected operating conditions by using hollow fiber polysulfone membranes. Then, the clarified liquor with a total solub...

  14. Vacuum pyrolysis and hydrometallurgical process for the recovery of valuable metals from spent lithium-ion batteries

    International Nuclear Information System (INIS)

    Highlights: → The cathode active materials LiCoO2 from spent lithium-ion batteries peeled completely from aluminum foils by vacuum pyrolysis and hydrometallurgical process. → The aluminum foils were excellent without damage after vacuum pyrolysis. → The pyrolysis products organic fluorine compounds from organic electrolyte and binder were collected and enriched. → High leaching efficiencies of cobalt and lithium were obtained with H2SO4 and H2O2. - Abstract: Spent lithium-ion batteries contain lots of strategic resources such as cobalt and lithium together with other hazardous materials, which are considered as an attractive secondary resource and environmental contaminant. In this work, a novel process involving vacuum pyrolysis and hydrometallurgical technique was developed for the combined recovery of cobalt and lithium from spent lithium-ion batteries. The results of vacuum pyrolysis of cathode material showed that the cathode powder composing of LiCoO2 and CoO peeled completely from aluminum foils under the following experimental conditions: temperature of 600 oC, vacuum evaporation time of 30 min, and residual gas pressure of 1.0 kPa. Over 99% of cobalt and lithium could be recovered from peeled cobalt lithium oxides with 2 M sulfuric acid leaching solution at 80 oC and solid/liquid ratio of 50 g L-1 for 60 min. This technology offers an efficient way to recycle valuable materials from spent lithium-ion batteries, and it is feasible to scale up and help to reduce the environmental pollution of spent lithium-ion batteries.

  15. Modeling and field observations of char bed processes in black liquor recovery boilers

    Energy Technology Data Exchange (ETDEWEB)

    Engblom, M.

    2010-07-01

    The char bed plays an important role in kraft black liquor combustion. Stable operation of the char bed promotes efficient and safe operation of the black liquor recovery boiler. It also plays a crucial role in the recovery of the pulping chemicals. Char bed operation involves controlling the char bed size and shape. Mathematical modeling based on computational fluid dynamics (CFD) haas been applied to recovery boilers for increased insights into the recovery furnace processes and to aid in the design of new boilers. So far, all CED-based char bed models reported in literature have used a fixed bed shape. This imposes restrictions on simulation of char bed burning by not considering inherently occurring changes in bed shape. In this thesis, a CED -based recovery furnace model is further developed to predict changes in bed shape. The new model is used in simulation of existing recovery boilers. The predictions of bed shape are compared with observations from real boilers. The furnace model is capable of correctly simulating the overall response of the char bed size to operational changes. This confirms the current quantitative overall understanding of char bed burning. In addition to modeling, visual observations of the char bed processes were made in this work. The observations provide validation data concerning the physical behavior of the char bed, and the findings from the observations can be used in further development of char bed models. Modeling and simulations of fundamental laboratory scale char bed experiments reported in literature are also carried out. The simulations complement the experimental data by providing detailed insights into gas phase reactions that can occur inside the gas boundary layer above a char bed. (orig.)

  16. Equipment and obtention process of phosphorus-32 starting from sulfur-32; Equipo y proceso de obtencion de fosforo-32 a partir del azufre-32

    Energy Technology Data Exchange (ETDEWEB)

    Alanis M, J. [ININ, Departamento de Materiales Radiactivos, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-12-15

    In the National Institute of Nuclear Research, it is the Radioisotopes Production plant, which covers in the area of the medicine 70% approximately of the national market and it exports to some countries of Latin America (Technetium-99, iodine-131, Sm-153 among other). At the moment the plant has modern facilities and certified with the ISO-9001-2000 standard, this, gives trust to the clients as for the quality of its products. Besides the production of radioisotopes dedicated for the medical area, the work of the plant tends to be more enlarged every time, producing new radioisotopes not only but with medical purposes but also industrial and agricultural ones, such it is the case of the production of Phosphorus-32 ({sup 32}P) that has applications with medical, industrial and in the agriculture purposes. The investigation studies from the prime matter (sulfur-32), sulfur purification, sulfur irradiation in the nuclear reactor and the obtaining process of {sup 32}P in a prototype, its took us to design and to build the obtaining process from {sup 32}P to more high level, which is presented in this work. To be able to select the obtaining method of {sup 32} P that is presented it was necessary to study the methods that have been developed in the world, later on it was selected the way that is presented. In that way the physical and chemical properties of the sulfur were studied which is used as prime matter, the interest nuclear reaction was also studied to carry out the production of {sup 32}P by means of the realization of mathematical calculations of irradiation of the sulfur in TRIGA Mark lll nuclear reactor. Once the sulfur is irradiated, it is necessary to carry out the radiochemical separation of the {sup 32}P produced from the sulfur, for this, it was necessary to carry out experimental tests of this separation, later on it was developed a prototype where it was carried out this separation and finally it was developed the final equipment of production of

  17. Processing of LEU targets for 99Mo production -- Dissolution of metal foils by nitric-acid/sulfuric-acid mixtures

    International Nuclear Information System (INIS)

    The first step in processing low-enriched uranium (LEU) targets for production of 99Mo is to dissolve the neutron-irradiated uranium foil coming from the reactor. Appropriate conditions for dissolving the foils were determined by measuring the dissolution rates for uranium foil over a wide range of temperatures and acid concentrations. On the basis of these dissolution rates, the process chemistry, and a model that integrates dissolution rates as a function of temperature and composition, a closed stainless-steel dissolver was designed, built, and tested for dissolving up to 18 g of uranium foil. The results were quite successful, with the uranium foil being dissolved within one hour as desired. To do this, the dissolver temperature must be in the range from 97 to 102 C, and the dissolver solution (cocktail) must have a composition of 3M nitric acid and 2M sulfuric acid. The final dissolver solution is subsequently processed to separate 99Mo from uranium, fission products, and other elements

  18. Processing of LEU targets for 99Mo production - Dissolution of metal foils by nitric-acid/sulfuric-acid mixtures

    International Nuclear Information System (INIS)

    The first step in processing low-enriched uranium (LEU) targets for production of 99Mo is to dissolve the neutron-irradiated uranium foil coming from the reactor. Appropriate conditions for dissolving the foils were determined by measuring the dissolution rates for uranium foil over a wide range of temperatures and acid concentrations. On the basis of these dissolution rates, the process chemistry, and a model that integrates dissolution rates as a function of temperature and composition, a closed stainless-steel dissolver was designed, built, and tested for dissolving up to 18 g of uranium foil. The results were quite successful, with the uranium foil being dissolved within one hour as desired. To do this, the dissolver temperature must be in the range from 97 to 102 deg. C, and the dissolver solution (cocktail) must have a composition of 3M nitric acid and ZM sulfuric acid. The final dissolver solution is subsequently processed to separate 99Mo from uranium, fission products, and other elements. (author)

  19. A Unified Process Model of Syntactic and Semantic Error Recovery in Sentence Understanding

    CERN Document Server

    Holbrook, J K; Mahesh, K; Holbrook, Jennifer K.; Eiselt, Kurt P.; Mahesh, Kavi

    1994-01-01

    The development of models of human sentence processing has traditionally followed one of two paths. Either the model posited a sequence of processing modules, each with its own task-specific knowledge (e.g., syntax and semantics), or it posited a single processor utilizing different types of knowledge inextricably integrated into a monolithic knowledge base. Our previous work in modeling the sentence processor resulted in a model in which different processing modules used separate knowledge sources but operated in parallel to arrive at the interpretation of a sentence. One highlight of this model is that it offered an explanation of how the sentence processor might recover from an error in choosing the meaning of an ambiguous word. Recent experimental work by Laurie Stowe strongly suggests that the human sentence processor deals with syntactic error recovery using a mechanism very much like that proposed by our model of semantic error recovery. Another way to interpret Stowe's finding is this: the human sente...

  20. Process for the separation and recovery of molybdenum and uranium from leach solution using ion exchange

    International Nuclear Information System (INIS)

    This invention provides a process for the recovery of uranium from a pregnant lixiviant containing molybdenum as the primary contaminant using a two-stage ion-exchange recovery process. In the first stage, a strong base anionic quaternary amine resin is employed to adsorb uranium and molybdenum values from the pregnant lixiviant. The uranium and molybdenum values are then eluted from the resin with a suitable eluant such as a salt solution which may contain carbonate or bicarbonate. In the second stage of the process, the pregnant eluate containing uranium and molybdenum is passed through a secondary column containing a weak acid cationic resin in its hydrogen form wherein the uranium values are adsorbed. The resin is then treated with an acid eluant to recover the uranium values. Finally the pregnant eluate containing uranium free of molybdenum is treated to precipitate uranium as yellow cake

  1. Bioregenerative technologies for waste processing and resource recovery in advanced space life support system

    Science.gov (United States)

    Chamberland, Dennis

    1991-01-01

    The Controlled Ecological Life Support System (CELSS) for producing oxygen, water, and food in space will require an interactive facility to process and return wastes as resources to the system. This paper examines the bioregenerative techologies for waste processing and resource recovery considered for a CELSS Resource Recovery system. The components of this system consist of a series of biological reactors to treat the liquid and solid material fractions, in which the aerobic and anaerobic reactors are combined in a block called the Combined Reactor Equipment (CORE) block. The CORE block accepts the human wastes, kitchen wastes, inedible refractory plant materials, grey waters from the CELLS system, and aquaculture solids and processes these materials in either aerobic or anaerobic reactors depending on the desired product and the rates required by the integrated system.

  2. Hydrometallurgical process for zinc recovery from electric arc furnace dust (EAFD)

    International Nuclear Information System (INIS)

    The present paper is the first of a series of two articles dealing with the development of an integrated process for the recovery of zinc from electric arc furnace dust (EAFD), a hazardous industrial waste generated in the collection of particulate material during steelmaking process via electric arc furnace. Part I presents the EAFD characterization and its leaching process by diluted sulphuric acid, whereas Part II deals with the purification of the leach liquor and the recovery of zinc by solvent extraction/electrowinning. The characterization of the examined electric arc furnace dust was carried out by using granulometry analysis, chemical analysis, X-ray diffraction (XRD), thermogravimetric/differential thermal analysis (TG/DTA) and scanning electron microscopy (SEM). The leaching process was based on the Zn extraction with diluted sulphuric acid from EAFD under atmospheric conditions and without using any preliminary treatment. Statistical design and analysis of experiments were used, in order to determine the main effects and interactions of the leaching process factors, which were: acid normality, temperature and solid to liquid ratio. The zinc recovery efficiency on the basis of EAFD weight reached 80%. X-ray diffraction and scanning electron microscopy were used for the characterization of the leached residues.

  3. Energy efficiency improvement of a Kraft process through practical stack gases heat recovery

    International Nuclear Information System (INIS)

    A process scheme for the optimal recovery of heat from stack gases considering energy and technical constraints has been developed and applied to an existing Kraft pulping mill. A system based on a closed loop recirculation of hot oil is used to recover the heat from stack gases and distribute it to the appropriate cold streams. The recovery of heat from stack gases is part of an overall optimization of the Kraft mill. Tools such as Pinch Analysis and exergy analysis are used to evaluate the process streams. The results indicate that 10.8 MW of heat from stack gases can be reused to heat process streams such as the deaerator water, hot water, drying filtrates, and black liquor. A simulation model of the recirculation loop has been developed to determine the specifications of the recovery system. The total heat exchanger surface area required by the system is 3460 m2, with a hot oil recirculation temperature of 137 oC. The anticipated total investment is $10.3 M, with a payback time of 1.8 years. - Highlights: → We developed a process design for recovering heat from stack gases in a Kraft mill. → The recovered heat is optimally distributed to the process cold streams. → Heat recovery system has a total surface area of 3500 m2 without gases condensation. → A reduction of 7 percent in total process steam demand is anticipated. → A total investment of 10.3 M$ is needed with a payback time of less than two years

  4. Sulfur isotope analysis of individual aerosol particles – a new tool for studying heterogeneous oxidation processes in the marine environment

    Directory of Open Access Journals (Sweden)

    B. W. Sinha

    2009-02-01

    Full Text Available Understanding the importance of the different oxidation pathways of sulfur dioxide (SO2 to sulfate is crucial for an interpretation of the climate effects of sulfate aerosols. Sulfur isotope analysis of atmospheric aerosol is a well established tool for identifying sources of sulfur in the atmosphere and assessment of anthropogenic influence. The power of this tool is enhanced by a new ion microprobe technique that permits isotope analysis of individual aerosol particles as small as 0.5 μm diameter. With this new single particle technique, different types of primary and secondary sulfates are first identified based on their chemical composition, and then their individual isotopic signature is measured. Our samples were collected at Mace Head, Ireland, a remote coastal station on the North Atlantic Ocean. Sea-salt-sulfate (10–60%, ammonium sulfate/sulfuric acid particles (15–65%, and non-sea-salt-sulfate (nss-sulfate on aged salt particles all contributed significantly to sulfate loadings in our samples.

    The isotopic composition of secondary sulfates depends on the isotopic composition of precursor SO2 and the oxidation process. The fractionation with respect to the source SO2 is poorly characterized. In the absence of conclusive laboratory experiments, we consider the kinetic fractionation of −9‰ during the gas phase oxidation of SO2 by OH as suggested by Saltzman et al. (1983 and Tanaka et al. (1994 to be the most reasonable estimate for the isotope fractionation during gas phase oxidation of SO2hom=0.991 and the equilibrium fractionation for the uptake of SO2(g into the aqueous phase and the dissociation to HSO3 of +16.5‰ measured by Eriksen (1972a to be the best approximation for the fractionation during oxidation in the aqueous phase (αhet=1.0165. The sulfur isotope ratio of secondary sulfate particles can

  5. Ionic flotation of complexing oxyanions. Thermodynamics of uranyl complexation in a sulfuric medium. Definition of selectivity conditions of the process

    International Nuclear Information System (INIS)

    Oxyanion ionic flotation process with dodecylamine hydrochloride as collector is studied by investigation of flotation and filtration recovery curves, suspension turbidity, conductimetric measurements, and solubility of ionic species. The process is controlled by chemical reactions of precipitation and by adsorption of surfactant confering hydrophobic or hydrophilic surface properties to the solid phase respectively when one or two monolayers of surfactant are successively adsorbed. Equilibrium constants (in terms of activity) of the uranium (VI) complexation with sulphate oxyanions are calculated through Raman spectroscopic study of uranyl sulphate aqueous solutions. The complexation results in a shift of the symmetrical stretching vibration band of U02 to low wavenumbers and an increase of their cross section. The solubility curves of ionic species in the precipitation of uranyl -sulphate complexes by dodecylamine hydrochloride are modelled. The knowledge of solubility products, activity coefficients of the species and critical micellar concentration of the surfactant allow the modelling of flotation recovery curves. Temperature and collector structure modifications are studied in terms of optimization parameters and uranium extraction of mine drainage water is processed. Residual concentration of surfactant is considerably lowered by adsorption on montmorillonite

  6. Retrofit of heat exchanger networks with pressure recovery of process streams at sub-ambient conditions

    International Nuclear Information System (INIS)

    Highlights: • New mathematical model for heat exchanger networks retrofit with pressure recovery. • Optimal heat and work integration applied to the retrofit of sub-ambient processes. • Streams pressure manipulation is used to enhance heat integration of the system. • Compressors and turbines can act on a coupling shaft and/or as stand-alone equipment. • Use of smaller amount of cold utilities, reducing significantly the operational costs. - Abstract: This paper presents a new mathematical programming model for the retrofit of heat exchanger networks (HENs), wherein the pressure recovery of process streams is conducted to enhance heat integration. Particularly applied to cryogenic processes, HENs retrofit with combined heat and work integration is mainly aimed at reducing the use of expensive cold services. The proposed multi-stage superstructure allows the increment of the existing heat transfer area, as well as the use of new equipment for both heat exchange and pressure manipulation. The pressure recovery of streams is carried out simultaneously with the HEN design, such that the process conditions (streams pressure and temperature) are variables of optimization. The mathematical model is formulated using generalized disjunctive programming (GDP) and is optimized via mixed-integer nonlinear programming (MINLP), through the minimization of the retrofit total annualized cost, considering the turbine and compressor coupling with a helper motor. Three case studies are performed to assess the accuracy of the developed approach, including a real industrial example related to liquefied natural gas (LNG) production. The results show that the pressure recovery of streams is efficient for energy savings and, consequently, for decreasing the HEN retrofit total cost especially in sub-ambient processes

  7. Network structure dependence on unconstrained isothermal-recovery processes for shape-memory thiol-epoxy "click" systems

    Science.gov (United States)

    Belmonte, Alberto; Fernández-Francos, Xavier; De la Flor, Silvia; Serra, Àngels

    2016-07-01

    The shape-memory response (SMR) of "click" thiol-epoxy polymers produced using latent catalysts, with different network structure and thermo-mechanical properties, was tested on unconstrained shape-recovery processes under isothermal conditions. Experiments at several programming temperatures ( T_{prog}) and isothermal-recovery temperatures ( T_{iso}) were carried out, and the shape-memory stability was analyzed through various consecutive shape-memory cycles. The temperature profile during the isothermal-recovery experiments was monitored, and it showed that the shape-recovery process takes place while the sample is becoming thermally stable and before stable isothermal temperature conditions are eventually reached. The shape-recovery process takes place in two different stages regardless of T_{iso}: a slow initial stage until the process is triggered at a temperature strongly related with the beginning of network relaxation, followed by the typical exponential decay of the relaxation processes until completion at a temperature below or very close to Tg. The shape-recovery process is slower in materials with more densely crosslinked and hindered network structures. The shape-recovery time ( t_{sr}) is significantly reduced when the isothermal-recovery temperature T_{iso} increases from below to above Tg because the network relaxation dynamics accelerates. However, the temperature range from the beginning to the end of the recovery process is hardly affected by T_{iso}; at higher T_{iso} it is only slightly shifted to higher temperatures. These results suggest that the shape-recovery process can be controlled by changing the network structure and working at T_{iso} < Tg to maximize the effect of the structure and/or by increasing T_{iso} to minimize the effect but increasing the shape-recovery rate.

  8. Network structure dependence on unconstrained isothermal-recovery processes for shape-memory thiol-epoxy "click" systems

    Science.gov (United States)

    Belmonte, Alberto; Fernández-Francos, Xavier; De la Flor, Silvia; Serra, Àngels

    2016-07-01

    The shape-memory response (SMR) of "click" thiol-epoxy polymers produced using latent catalysts, with different network structure and thermo-mechanical properties, was tested on unconstrained shape-recovery processes under isothermal conditions. Experiments at several programming temperatures ( T_{prog}) and isothermal-recovery temperatures ( T_{iso}) were carried out, and the shape-memory stability was analyzed through various consecutive shape-memory cycles. The temperature profile during the isothermal-recovery experiments was monitored, and it showed that the shape-recovery process takes place while the sample is becoming thermally stable and before stable isothermal temperature conditions are eventually reached. The shape-recovery process takes place in two different stages regardless of T_{iso}: a slow initial stage until the process is triggered at a temperature strongly related with the beginning of network relaxation, followed by the typical exponential decay of the relaxation processes until completion at a temperature below or very close to Tg. The shape-recovery process is slower in materials with more densely crosslinked and hindered network structures. The shape-recovery time ( t_{sr}) is significantly reduced when the isothermal-recovery temperature T_{iso} increases from below to above Tg because the network relaxation dynamics accelerates. However, the temperature range from the beginning to the end of the recovery process is hardly affected by T_{iso}; at higher T_{iso} it is only slightly shifted to higher temperatures. These results suggest that the shape-recovery process can be controlled by changing the network structure and working at T_{iso} structure and/or by increasing T_{iso} to minimize the effect but increasing the shape-recovery rate.

  9. Assessing Landscape Change and Processes of Recurrence, Replacement, and Recovery in the Southeastern Coastal Plains, USA

    Science.gov (United States)

    Drummond, Mark A.; Stier, Michael P.; Auch, Roger F.; Taylor, Janis L.; Griffith, Glenn E.; Riegle, Jodi L.; Hester, David J.; Soulard, Christopher E.; McBeth, Jamie L.

    2015-11-01

    The processes of landscape change are complex, exhibiting spatial variability as well as linear, cyclical, and reversible characteristics. To better understand the various processes that cause transformation, a data aggregation, validation, and attribution approach was developed and applied to an analysis of the Southeastern Coastal Plains (SECP). The approach integrates information from available national land-use, natural disturbance, and land-cover data to efficiently assess spatially-specific changes and causes. Between 2001 and 2006, the processes of change affected 7.8 % of the SECP but varied across small-scale ecoregions. Processes were placed into a simple conceptual framework to explicitly identify the type and direction of change based on three general characteristics: replacement, recurrence, and recovery. Replacement processes, whereby a land use or cover is supplanted by a new land use, including urbanization and agricultural expansion, accounted for approximately 15 % of the extent of change. Recurrent processes that contribute to cyclical changes in land cover, including forest harvest/replanting and fire, accounted for 83 %. Most forest cover changes were recurrent, while the extents of recurrent silviculture and forest replacement processes such as urbanization far exceeded forest recovery processes. The total extent of landscape recovery, from prior land use to natural or semi-natural vegetation cover, accounted for less than 3 % of change. In a region of complex change, increases in transitory grassland and shrubland covers were caused by large-scale intensive plantation silviculture and small-scale activities including mining reclamation. Explicit identification of the process types and dynamics presented here may improve the understanding of land-cover change and landscape trajectory.

  10. Design of Hybrid Steam-In Situ Combustion Bitumen Recovery Processes

    International Nuclear Information System (INIS)

    Given enormous capital costs, operating expenses, flue gas emissions, water treatment and handling costs of thermal in situ bitumen recovery processes, improving the overall efficiency by lowering energy requirements, environmental impact, and costs of these production techniques is a priority. Steam-assisted gravity drainage (SAGD) is the most widely used in situ recovery technique in Athabasca reservoirs. Steam generation is done on surface and consequently, because of heat losses, the energy efficiency of SAGD can never be ideal with respect to the energy delivered to the sandface. An alternative to surface steam generation is in situ combustion (ISC) where heat is generated within the formation through injection of oxygen at a sufficiently high pressure to initiate combustion of bitumen. In this manner, the heat from the combustion reactions can be used directly to mobilize the bitumen. As an alternative, the heat can be used to generate steam within the formation which then is the agent to move heat in the reservoir. In this research, alternative hybrid techniques with simultaneous and sequential steam-oxygen injection processes are examined to maximize the thermal efficiency of the recovery process. These hybrid processes have the advantage that during ISC, steam is generated within the reservoir from injected and formation water and as a product of oxidation. This implies that ex situ steam generation requirements are reduced and if there is in situ storage of combustion gases, that overall gas emissions are reduced. In this research, detailed reservoir simulations are done to examine the dynamics of hybrid processes to enable design of these processes. The results reveal that hybrid processes can lower emitted carbon dioxide-to-oil ratio by about 46%, decrease the consumed natural gas-to-oil ratio by about 73%, reduce the cumulative energy-to-oil ratio by between 40% and 70% compared to conventional SAGD, and drop water consumption per unit oil produced

  11. Sulfomethylated lignite salt as a sacrifical agent in oil recovery processes

    Energy Technology Data Exchange (ETDEWEB)

    Kudchadker, M.V.; Weiss, W.J.

    1978-02-07

    A process is described for recovering petroleum from oil reservoirs by secondary recovery methods. The process involves injecting via an injection well into the reservoir an aqueous solution of sulfomethylated lignite salt as a sacrificial agent to inhibit the deposition of surfactant and polymer on the reservoir matrix. The process is conducted by first injecting the lignite salt into the formation through the injection well and following it with either a polymer or a surfactant solution, which also may contain the lignite salt. The polymer or surfactant would then be followed by a drive fluid, such as water, to push the chemicals and oil to the production well. (18 claims)

  12. Modified Purex process for the separation and recovery of plutonium--uranium residues

    Energy Technology Data Exchange (ETDEWEB)

    Navratil, J.D.; Leebl, R.G.

    1978-07-08

    A modified (one-cycle) Purex process has been developed for the separation and recovery of plutonium and uranium from mixed actinide residues. The process utilizes 30 vol % tributyl phosphate--dodecane to extract uranium from a 5M nitric acid-plutonium (III)-uranium(VI) feed. After uranium extraction, plutonium in the aqueous feed solution is purified by anion exchange technology. Uranium in the organic is scrubbed and stripped to effectively purify the uranium so that it contains <5,000 ppM plutonium. The process has been used successfully to separate residues consisting of plutonium and uranium oxide.

  13. Water recovery and solid waste processing for aerospace and domestic applications. Volume 1: Final report

    Science.gov (United States)

    Murray, R. W.

    1973-01-01

    A comprehensive study of advanced water recovery and solid waste processing techniques employed in both aerospace and domestic or commercial applications is reported. A systems approach was used to synthesize a prototype system design of an advanced water treatment/waste processing system. Household water use characteristics were studied and modified through the use of low water use devices and a limited amount of water reuse. This modified household system was then used as a baseline system for development of several water treatment waste processing systems employing advanced techniques. A hybrid of these systems was next developed and a preliminary design was generated to define system and hardware functions.

  14. A business process for enhanced heavy oil recovery research and development

    International Nuclear Information System (INIS)

    Husky Oil's enhanced oil recovery (EOR) research management processes for reducing process development time and increasing investment efficiency were described. The considerations that went into the development of the plan a decade ago were reviewed and new ideas incorporated into the revised plan were presented. Four case studies were presented to illustrate the need for process to reservoir matching. A need for strategic research planning was emphasized. Proposed technologies for enhancement of heavy oil reservoir productivity were presented in tabular form. 1 tab., 7 figs

  15. A microencapsulation process of liquid mercury by sulfur polymer stabilization/solidification technology. Part II: Durability of materials

    Directory of Open Access Journals (Sweden)

    López-Delgado, A.

    2012-02-01

    Full Text Available Under the European LIFE Program a microencapsulation process was developed for liquid mercury using Sulfur Polymer Stabilization/Solidification (SPSS technology, obtaining a stable concrete-like sulfur matrix that allows the immobilization of mercury for long-term storage. The process description and characterization of the materials obtained were detailed in Part I. The present document, Part II, reports the results of different tests carried out to determine the durability of Hg-S concrete samples with very high mercury content (up to 30 % w/w. Different UNE and RILEM standard test methods were applied, such as capillary water absorption, low pressure water permeability, alkali/acid resistance, salt mist aging, freeze-thaw resistance and fire performance. The samples exhibited no capillarity and their resistance in both alkaline and acid media was very high. They also showed good resistance to very aggressive environments such as spray salt mist, freeze-thaw and dry-wet. The fire hazard of samples at low heat output was negligible.

    Dentro del Programa Europeo LIFE, se ha desarrollado un proceso de microencapsulación de mercurio liquido, utilizando la tecnología de estabilización/solidificación con azufre polimérico (SPSS. Como resultado se ha obtenido un material estable tipo concreto que permite la inmovilización de mercurio y su almacenamiento a largo plazo. La descripción del proceso y la caracterización de los materiales obtenidos, denominados concretos Hg-S, se detallan en la Parte I. El presente trabajo, Parte II, incluye los resultados de los diferentes ensayos realizados para determinar la durabilidad de las muestras de concreto Hg-S con un contenido de mercurio de hasta el 30 %. Se han utilizado diferentes métodos de ensayo estándar, UNE y RILEM, para determinar propiedades como la absorción de agua por capilaridad, la permeabilidad de agua a baja presión, la resistencia a álcali y ácido, el comportamiento en

  16. Advanced Thermoelectric Materials for Efficient Waste Heat Recovery in Process Industries

    Energy Technology Data Exchange (ETDEWEB)

    Adam Polcyn; Moe Khaleel

    2009-01-06

    The overall objective of the project was to integrate advanced thermoelectric materials into a power generation device that could convert waste heat from an industrial process to electricity with an efficiency approaching 20%. Advanced thermoelectric materials were developed with figure-of-merit ZT of 1.5 at 275 degrees C. These materials were not successfully integrated into a power generation device. However, waste heat recovery was demonstrated from an industrial process (the combustion exhaust gas stream of an oxyfuel-fired flat glass melting furnace) using a commercially available (5% efficiency) thermoelectric generator coupled to a heat pipe. It was concluded that significant improvements both in thermoelectric material figure-of-merit and in cost-effective methods for capturing heat would be required to make thermoelectric waste heat recovery viable for widespread industrial application.

  17. Evolution of seismic velocities in heavy oil sand reservoirs during thermal recovery process

    CERN Document Server

    Nauroy, Jean-François; Guy, N; Baroni, Axelle; Delage, Pierre; Mainguy, Marc; 10.2516/ogst/2012027

    2013-01-01

    In thermally enhanced recovery processes like cyclic steam stimulation (CSS) or steam assisted gravity drainage (SAGD), continuous steam injection entails changes in pore fluid, pore pressure and temperature in the rock reservoir, that are most often unconsolidated or weakly consolidated sandstones. This in turn increases or decreases the effective stresses and changes the elastic properties of the rocks. Thermally enhanced recovery processes give rise to complex couplings. Numerical simulations have been carried out on a case study so as to provide an estimation of the evolution of pressure, temperature, pore fluid saturation, stress and strain in any zone located around the injector and producer wells. The approach of Ciz and Shapiro (2007) - an extension of the poroelastic theory of Biot-Gassmann applied to rock filled elastic material - has been used to model the velocity dispersion in the oil sand mass under different conditions of temperature and stress. A good agreement has been found between these pre...

  18. Modeling the effects of ore properties on water recovery in the thickening process

    Science.gov (United States)

    Unesi, Majid; Noaparast, Mohammad; Shafaei, Seiyd Ziaedin; Jorjani, Esmaeil

    2014-09-01

    A better understanding of solid-liquid separation would assist in improving the thickening performance and perhaps water recovery as well. The present work aimed to develop an empirical model to study the effects of ore properties on the thickening process based on pilot tests using a column. A hydro-cyclone was used to prepare the required samples for the experiments. The model significantly predicted the experimental underflow solid content using a regression equation at a given solid flux and bed level for different samples, indicating that ore properties are the effective parameters in the thickening process. This work confirmed that the water recovery would be increased about 5% by separating the feed into two parts, overflow and underflow, and introducing two different thickeners into them separately. This is duo to the fact that thickeners are limited by permeability and compressibility in operating conditions.

  19. Flux Recovery of a Forward Osmosis Membrane After a Fouling Process

    Science.gov (United States)

    Romero-Mangado, Jaione; Parodi, Jurek; Gamboa-Vazquez, Sonia; Stefanson, Ofir; Diaz-Cartagena, Diana C.; Flynn, Michael

    2016-01-01

    Wastewater treatment through forward osmosis (FO) membranes is a process that has been evaluated in the past years as an innovative technology for the Next Generation Life Support Systems. FO technologies are cost effective, and require very low energy consumption, but are subject to membrane fouling. Membrane fouling occurs when unwanted materials accumulate on the active side of the membrane during the wastewater treatment process, which leads to a decrease in membrane flux rate. The aim of this study is to identify the materials that cause flux rate reduction due to membrane fouling, as well as to evaluate the flux rate recovery after membrane treatment using commercially available antifoulants. Fourier Transform Infrared (FTIR) spectrometry results identified possible compounds that cause membrane fouling and FO testing results demonstrated flux rate recovery after membrane treatment using antifoulants.

  20. Flux Recovery of a Forward Osmosis Membrane After a Fouling Process

    Science.gov (United States)

    Gamboa-Vázquez, Sonia; Flynn, Michael; Romero Mangado, Jaione; Parodi, Jurek

    2016-01-01

    Wastewater treatment through Forward Osmosis (FO) membranes is a process that has been evaluated in the past years as an innovative technology for the Next Generation Life Support Systems. FO technologies are cost effective, and require very low energy consumption, but are subject to membrane fouling. Membrane fouling occurs when unwanted materials accumulate on the active side of the membrane during the wastewater treatment process, which leads to a decrease in membrane flow rates. Membrane fouling can be reversed with the use of antifoulant solutions. The aim of this study is to identify the materials that cause flow rate reduction due to membrane fouling, as well as to evaluate the flux recovery after membrane treatment using commercially available antifoulants. 3D Laser Scanning Microscope images were taken to observe the surface of the membrane. Fourier Transform Infrared (FTIR) spectrometry results identified possible compounds that cause membrane fouling and FO testing results demonstrated flow rate recovery after membrane treatment using antifoulants.

  1. Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Dandina N. Rao; Subhash C. Ayirala; Madhav M. Kulkarni; Wagirin Ruiz Paidin; Thaer N. N. Mahmoud; Daryl S. Sequeira; Amit P. Sharma

    2006-09-30

    This is the final report describing the evolution of the project ''Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery'' from its conceptual stage in 2002 to the field implementation of the developed technology in 2006. This comprehensive report includes all the experimental research, models developments, analyses of results, salient conclusions and the technology transfer efforts. As planned in the original proposal, the project has been conducted in three separate and concurrent tasks: Task 1 involved a physical model study of the new GAGD process, Task 2 was aimed at further developing the vanishing interfacial tension (VIT) technique for gas-oil miscibility determination, and Task 3 was directed at determining multiphase gas-oil drainage and displacement characteristics in reservoir rocks at realistic pressures and temperatures. The project started with the task of recruiting well-qualified graduate research assistants. After collecting and reviewing the literature on different aspects of the project such gas injection EOR, gravity drainage, miscibility characterization, and gas-oil displacement characteristics in porous media, research plans were developed for the experimental work to be conducted under each of the three tasks. Based on the literature review and dimensional analysis, preliminary criteria were developed for the design of the partially-scaled physical model. Additionally, the need for a separate transparent model for visual observation and verification of the displacement and drainage behavior under gas-assisted gravity drainage was identified. Various materials and methods (ceramic porous material, Stucco, Portland cement, sintered glass beads) were attempted in order to fabricate a satisfactory visual model. In addition to proving the effectiveness of the GAGD process (through measured oil recoveries in the range of 65 to 87% IOIP), the visual models demonstrated

  2. Richness and species composition of ants in the recovery process of a gully erosion

    OpenAIRE

    Gabriel Biagiotti; José Aldo Alves Pereira; Carla Rodrigues Ribas; Vanesca Korasaki; Ronald Zanetti; Antônio César Medeiros de Queiroz

    2013-01-01

    This study aimed to determine how the richness and composition of ant species behaves with changes in the recovery process of a gully erosion. The study area has 0.9 hectares subdivided into three sections called sector: "A", "B" and "C". For the definition of the sectors, erosive and natural restoring were taken as the base level of activity. Four transects were laid systematically throughout the area and surrounding compound with forest and grassland. Each transect had three "pitfall trap" ...

  3. Process for the recovery of magnesium and/or nickel by liquid-liquid extraction

    Energy Technology Data Exchange (ETDEWEB)

    Gabra, G.

    1984-02-14

    The recovery of substantially pure magnesium and/or nickel sulphite which is present in a solid starting meterial. The latter is treated with gaseous SO/sub 2/ in water, the solution obtained is treated by a liquid-liquid extraction, to give an aqueous phase and an organic phase and the magnesium and/or nickel sulphite is recovered from the aqueous phase. With this process, it is possible to obtain a magnesium salt of high purity.

  4. An iron-facilitated chemical and biological process for phosphorus removal and recovery during wastewater treatment

    OpenAIRE

    Zhao, Kang; 趙鈧

    2013-01-01

    Phosphorus (P) is an important pollutant of concern in wastewater that causes eutrophication and algal blooms in water body. On the other hand, P is a valuable natural resource for agricultural and industrial use. With the rapid depletion of mineral phosphorus on earth, there is a need to recover phosphorus from wastewater. In this study, a new chemical and biological process facilitated with iron dosing has been developed for P removal and recovery during wastewater treatment. The system con...

  5. Process of recovery and reuse of the washing liquids from filters

    International Nuclear Information System (INIS)

    The present invention relates to a backflush procedure intended for a repeated recovery and reuse of the liquid used for washing a 'pre-layer' filter. This type of filter is used for purifying the water of the steam generator circuit in electric energy generating plants equipped with steam turbines. Said 'pre-layer' filter can also be applied in the auxiliary facilities of electric energy generating plants, especially for treating the fuel ponds in nuclear reactors and for radioactive waste processing

  6. A contribution to resource recovery from wastewater. Anaerobic processes for organic matter and nitrogen treatment

    OpenAIRE

    Basset Olivé, Núria

    2015-01-01

    Organic matter and nutrients present in urban and industrial wastewater should be removed or valorised to reduce its impact on the environment. Conventional wastewater treatments are focused on the removal of these pollution sources at the minimum cost. The idea of resource recovery from wastewater is changing the concept of the conventional wastewater treatment plants that tend to incorporate little by little processes as anaerobic digestion, MBR, biofilm, granulation, etc. However, their ap...

  7. The acid aging as alternative process for uranium recovery from silicated ores

    International Nuclear Information System (INIS)

    The influence of different variables on the extraction uranium efficiency and on the silicate solubility by means of acid aging is studied. The variables studied in bench scale were: acid/ore, oxidizing/ore and liquid/solid relationships; reaction time; temperature and recovery time. The results are discussed and compared with the ones of continuous operation of a semi-pilot plant. A flowsheet of the industrial process application is presented. (M.A.C.)

  8. The Effects of Children on the Process of Recovery in Oxford Houses.

    Science.gov (United States)

    Legler, Ray; Chiaramonte, Danielle; Patterson, Meaghan; Allis, Ashley; Runion, Hilary; Jason, Leonard

    2012-01-01

    The effects of children on the process of substance use recovery for adults living in Oxford Houses is explored in two qualitative studies. Oxford Houses are self-run, community-based residential homes for small groups of adults who live together and support each other's efforts to recover from drug and/or alcohol addiction. In the first study, telephone interviews were conducted with 29 adults who were living in Oxford Houses that allowed children to live in the house with their parent. Results suggest that having children in the house supported a positive living environment for the recovery of house members. In the second study, telephone interviews were conducted with an additional 15 mothers who lived in Oxford Houses. These interviews focused on the effects of the mothers' addiction and recovery on their relationships with their children. This study found that most parents acknowledged the negative effects of their addiction on their relationship with their child and the effects of their recovery on improving those relationships. PMID:23875179

  9. Yttrium recovery from primary and secondary sources: A review of main hydrometallurgical processes

    International Nuclear Information System (INIS)

    Highlights: • Review of the main hydrometallurgical processes to recover yttrium. • Recovery of yttrium from primary sources. • Recovery of yttrium from e-waste and other types of waste. - Abstract: Yttrium is important rare earths (REs) used in numerous fields, mainly in the phosphor powders for low-energy lighting. The uses of these elements, especially for high-tech products are increased in recent years and combined with the scarcity of the resources and the environmental impact of the technologies to extract them from ores make the recycling waste, that contain Y and other RE, a priority. The present review summarized the main hydrometallurgical technologies to extract Y from ores, contaminated solutions, WEEE and generic wastes. Before to discuss the works about the treatment of wastes, the processes to retrieval Y from ores are discussed, since the processes are similar and derived from those already developed for the extraction from primary sources. Particular attention was given to the recovery of Y from WEEE because the recycle of them is important not only for economical point of view, considering its value, but also for environmental impact that this could be generated if not properly disposal

  10. Study on incineration technology of oil gas generated during the recovery process of oil spill

    International Nuclear Information System (INIS)

    The objective of this study is to design, set up and operate an incinerator system capable of providing clean exhaust and safety control for burning oil gas generated during the recovery process of oil spill in Taiwan. In this study, we successfully develop a vertical-type incinerator, which consists of five oil gas burners with entrained primary air, a pilot burner, and an auxiliary burner. The incinerator system is equipped with necessary control units in order to achieve safe, easy, fast, and efficient operation. Flame appearance, flue gas temperature and CO emission of the incinerator system for burning oil gas are reported and discussed. Under the long-term operation, it is found that the new designed incinerator is satisfactory for burning oil gas with low supply pressure at various compositions and supply rates during the recovery process of oil spill. It is noteworthy that the results obtained herein are of great significance to provide a good guidance for those who need to design, set up and operate an incinerator system providing clean exhaust and safety control for burning oil gas generated during the recovery process of oil spill in a polluted site with a large area.

  11. Interfacing the tandem mirror reactor to the sulfur-iodine process for hydrogen production

    International Nuclear Information System (INIS)

    The blanket is linked to the H2SO4 vaporization units and SO3 decomposition reactor with either sodium or helium. The engineering and safety problems associated with these choices are discussed. This H2SO4 step uses about 90% of the TMR heat and is best close-coupled to the nuclear island. The rest of the process we propose to be driven by steam and does not require close-coupling. The sodium loop coupling seems to be preferable at this time. We can operate with a blanket around 1200 K and the SO3 decomposer around 1050 K. This configuration offers double-barrier protection between Li-Na and the SO3 process gases. Heat pipes offer an attractive alternate to provide an additional barrier, added modularity for increased reliability, and tritium concentration and isolation operations with very little thermal penalty

  12. Clean recovery of antioxidant compounds from plant foods, by-products and algae assisted by ultrasounds processing. Modeling approaches to optimize processing conditions

    DEFF Research Database (Denmark)

    Roselló-Soto, Elena; Galanakis, Charis M.; Brnčić, Mladen;

    2015-01-01

    Ultrasound treatment is an alternative affordable, effective and reproducible method for the improved recovery of bioactive compounds from various processing streams. The objective of this review is to discuss the impact of ultrasound-assisted extraction on the recovery of polyphenols, carotenoids...... biological activity of the extract. Modeling strategies to characterize and optimize ultrasound processes are also be highlighted in the manuscript....

  13. Waste processing cost recovery at Los Alamos National Laboratory--analysis and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Booth, Steven Richard [Los Alamos National Laboratory

    2008-01-01

    Los Alamos National Laboratory is implementing full cost recovery for waste processing in fiscal year 2009 (FY2009), after a transition year in FY2008. Waste processing cost recovery has been implemented in various forms across the nuclear weapons complex and in corporate America. The fundamental reasoning of sending accurate price signals to waste generators is economically sound, and leads to waste minimization and reduced waste expense over time. However, Los Alamos faces significant implementation challenges because of its status as a government-owned, contractor-operated national scientific institution with a diverse suite of experimental and environmental cleanup activities, and the fact that this represents a fundamental change in how waste processing is viewed by the institution. This paper describes the issues involved during the transition to cost recovery and the ultimate selection of the business model. Of the six alternative cost recovery models evaluated, the business model chosen to be implemented in FY2009 is Recharge Plus Generators Pay Distributed Direct. Under this model, all generators who produce waste must pay a distributed direct share associated with their specific waste type to use a waste processing capability. This cost share is calculated using the distributed direct method on the fixed cost only, i.e., the fixed cost share is based on each program's forecast proportion of the total Los Alamos volume forecast of each waste type. (Fixed activities are those required to establish the waste processing capability, i.e., to make the process ready, permitted, certified, and prepared to handle the first unit ofwaste. Therefore, the fixed cost ends at the point just before waste begins 'to be processed. The activities to actually process the waste are considered variable.) The volume of waste actually sent for processing is charged a unit cost based solely on the variable cost of disposing of that waste. The total cost recovered each

  14. Processes for preparing carbon fibers using sulfur trioxide in a halogenated solvent

    Science.gov (United States)

    Patton, Jasson T.; Barton, Bryan E.; Bernius, Mark T.; Chen, Xiaoyun; Hukkanen, Eric J.; Rhoton, Christina A.; Lysenko, Zenon

    2015-12-29

    Disclosed here are processes for preparing carbonized polymers (preferably carbon fibers), comprising sulfonating a polymer with a sulfonating agent that comprises SO.sub.3 dissolved in a solvent to form a sulfonated polymer; treating the sulfonated polymer with a heated solvent, wherein the temperature of the solvent is at least 95.degree. C.; and carbonizing the resulting product by heating it to a temperature of 500-3000.degree. C. Carbon fibers made according to these methods are also disclosed herein.

  15. Recovery of protactinium-231 and thorium-230 from cotter concentrate: pilot plant operatins and process development

    International Nuclear Information System (INIS)

    The equipment and methods used to recover and purify 339 g of thorium-230 and 890 mg of protactinium-231 from 22 of the 1251 drums of Cotter Concentrate are described. The process developed was (1) dissolution at 1000C in concentrated nitric acid and dilution to 2 to 3 molar acid, (2) filtration to remove undissolved solids (mostly silica filter aid), (3) extraction of uranium with di-sec-butyl-phenyl phophonate (DSBPP) in carbon tetrachloride, (4) extraction of both thorium and protactinium with tri-n-octylphosphine oxide (TOPO) in carbon tetrachloride followed by selective stripping of the thorium with dilute of sulfuric acid, (5) thorium purification using oxalic acid, (6) stripping protactinium from the TOPO with oxalic acid, and (7) protactinium purification through a sequence of steps. The development of the separation procedures, the design of the pilot plant, and the operating procedures are described in detail. Analytical procedures are given in an appendix. 8 figures, 4 tables

  16. Recovery of protactinium-231 and thorium-230 from cotter concentrate: pilot plant operatins and process development

    Energy Technology Data Exchange (ETDEWEB)

    Hertz, M.R.; Figgins, P.E.; Deal, W.R.

    1983-02-10

    The equipment and methods used to recover and purify 339 g of thorium-230 and 890 mg of protactinium-231 from 22 of the 1251 drums of Cotter Concentrate are described. The process developed was (1) dissolution at 100/sup 0/C in concentrated nitric acid and dilution to 2 to 3 molar acid, (2) filtration to remove undissolved solids (mostly silica filter aid), (3) extraction of uranium with di-sec-butyl-phenyl phophonate (DSBPP) in carbon tetrachloride, (4) extraction of both thorium and protactinium with tri-n-octylphosphine oxide (TOPO) in carbon tetrachloride followed by selective stripping of the thorium with dilute of sulfuric acid, (5) thorium purification using oxalic acid, (6) stripping protactinium from the TOPO with oxalic acid, and (7) protactinium purification through a sequence of steps. The development of the separation procedures, the design of the pilot plant, and the operating procedures are described in detail. Analytical procedures are given in an appendix. 8 figures, 4 tables.

  17. Sulfur cycle

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.

    Microbes, especially bacteria, play an important role in oxidative and reductive cycle of sulfur. The oxidative part of the cycle is mediated by photosynthetic bacteria in the presence of light energy and chemosynthetic forms in the absence of light...

  18. Process technology for production and recovery of heterologous proteins with Pichia pastoris.

    Science.gov (United States)

    Jahic, Mehmedalija; Veide, Andres; Charoenrat, Theppanya; Teeri, Tuula; Enfors, Sven-Olof

    2006-01-01

    Developments in process techniques for production and recovery of heterologous proteins with Pichia pastoris are presented. Limitations for the standard techniques are described, and alternative techniques that solve the limitations problems are reviewed together with the methods that resulted in higher productivity of the P. pastoris processes. The main limitations are proteolysis of the secreted products and cell death in the high cell density bioreactor cultures. As a consequence, both low productivity and lower quality of the feedstock for downstream processing are achieved in processes hampered with these problems. Methods for exploring proteolysis and cell death are also presented. Solving the problems makes the conditions for downstream processing superior for the P. pastoris expression systems compared to other systems, which either need complex media or rely on intracellular production. These improved conditions allow for interfacing of cultivation with downstream processing in an integrated fashion. PMID:17137292

  19. Crystallization behaviour of co-sputtered Cu₂ZnSnS₄ precursor prepared by sequential sulfurization processes.

    Science.gov (United States)

    Han, Junhee; Shin, Seung Wook; Gang, Myeong Gil; Kim, Jin Hyeok; Lee, Jeong Yong

    2013-03-01

    Cu(2)ZnSnS(4) (CZTS) thin films were prepared by the sequential sulfurization of a co-sputtered precursor with a multitarget (Cu, ZnS, and SnS(2)) sputtering system. In order to investigate the crystallization behaviour of the thin films, the precursors were sulfurized in a tube furnace at different temperatures for different time durations. The Raman spectra of the sulfurized thin films showed that their crystallinity gradually improved with an increase in the sulfurization temperature and duration. However, transmission electron microscopy revealed an unexpected result-the precursor thin films were not completely transformed to the CZTS phase and showed the presence of uncrystallized material when sulfurized at 250-400 °C for 60 min and at 500 °C for 30 min. Thus, the crystallization of the co-sputtered precursor thin films showed a strong dependence on the sulfurization temperature and duration. The crystallization mechanism of the precursor thin films was understood on the basis of these results and has been described in this paper. The understanding of this mechanism may improve the standard preparation method for high-quality CZTS absorber layers. PMID:23396187

  20. Crystallization behaviour of co-sputtered Cu2ZnSnS4 precursor prepared by sequential sulfurization processes

    International Nuclear Information System (INIS)

    Cu2ZnSnS4 (CZTS) thin films were prepared by the sequential sulfurization of a co-sputtered precursor with a multitarget (Cu, ZnS, and SnS2) sputtering system. In order to investigate the crystallization behaviour of the thin films, the precursors were sulfurized in a tube furnace at different temperatures for different time durations. The Raman spectra of the sulfurized thin films showed that their crystallinity gradually improved with an increase in the sulfurization temperature and duration. However, transmission electron microscopy revealed an unexpected result—the precursor thin films were not completely transformed to the CZTS phase and showed the presence of uncrystallized material when sulfurized at 250–400 °C for 60 min and at 500 °C for 30 min. Thus, the crystallization of the co-sputtered precursor thin films showed a strong dependence on the sulfurization temperature and duration. The crystallization mechanism of the precursor thin films was understood on the basis of these results and has been described in this paper. The understanding of this mechanism may improve the standard preparation method for high-quality CZTS absorber layers. (paper)

  1. An application of CAMx process analysis tools: Exploring process contributions to extreme ozone, nitrogen oxides and sulfur dioxide

    Science.gov (United States)

    Murray, David-anthony

    The University at Albany Air Quality Forecasting Modeling System (AQFMS) is a state-of-the-art model that generates reliable daily and "day-ahead" air quality forecasts for the Northeastern United States. The three major categories of processes which dictate regional air quality are production from emission sources, horizontal and vertical transport driven by the prevailing meteorology, and chemical transformations. The Advanced Research WRF (ARW) produces meteorological fields. The Sparse Matrix Operator for Kernel Emissions (SMOKE) processes available emission inventories for air quality modeling. The Comprehensive Air Quality Model with extension (CAMx) handles both chemical processes and the integration of ARW-WRF and SMOKE in devising separate quantitative contributions to pollutant concentrations from process categories. An AQFMS forecast, though indicative of the temporal and spatial changes in the ambient condition, does not tell us exactly how and why those changes occurred. High concentrations of criteria pollutants during "extreme" conditions could come about in many ways. Process analysis takes a step back in numerical procedures to showcase the partial contribution of 18 different processes to the predicted concentration. Area and point source make up the two emission source processes. Advection and diffusion through the west, east, south, north, bottom and top boundary make up the twelve horizontal and vertical transport processes. Gas phase and heterogeneous chemistry make up the two chemical transformation processes, with dry and wet deposition making up the two physio-chemical removal processes. A group of model defined "extreme" intra-day periods in a 12km by 12km grid spacing over The New York Botanical Gardens were evaluated for model performance at the surface and characterized by distinctive modes in which the aforementioned processes contribute to SO2, NOx and O3 concentrations in the vertical layers up to the first 4km of the model

  2. A New Screening Methodology for Improved Oil Recovery Processes Using Soft-Computing Techniques

    Science.gov (United States)

    Parada, Claudia; Ertekin, Turgay

    2010-05-01

    The first stage of production of any oil reservoir involves oil displacement by natural drive mechanisms such as solution gas drive, gas cap drive and gravity drainage. Typically, improved oil recovery (IOR) methods are applied to oil reservoirs that have been depleted naturally. In more recent years, IOR techniques are applied to reservoirs even before their natural energy drive is exhausted by primary depletion. Descriptive screening criteria for IOR methods are used to select the appropriate recovery technique according to the fluid and rock properties. This methodology helps in assessing the most suitable recovery process for field deployment of a candidate reservoir. However, the already published screening guidelines neither provide information about the expected reservoir performance nor suggest a set of project design parameters, which can be used towards the optimization of the process. In this study, artificial neural networks (ANN) are used to build a high-performance neuro-simulation tool for screening different improved oil recovery techniques: miscible injection (CO2 and N2), waterflooding and steam injection processes. The simulation tool consists of proxy models that implement a multilayer cascade feedforward back propagation network algorithm. The tool is intended to narrow the ranges of possible scenarios to be modeled using conventional simulation, reducing the extensive time and energy spent in dynamic reservoir modeling. A commercial reservoir simulator is used to generate the data to train and validate the artificial neural networks. The proxy models are built considering four different well patterns with different well operating conditions as the field design parameters. Different expert systems are developed for each well pattern. The screening networks predict oil production rate and cumulative oil production profiles for a given set of rock and fluid properties, and design parameters. The results of this study show that the networks are

  3. Effects of processing on the transverse fatigue properties of low-sulfur AISI 4140 steel

    Science.gov (United States)

    Collins, Sunniva R.; Michal, Gary M.

    1993-12-01

    The effects of inclusions due to steelmaking processes on the fatigue life of AISI 4140 have been investigated. The test matrix consisted of three commercially produced heats of AISI 4140 of comparable cleanliness: one was conventionally cast (CC), and two were inert gas-shielded/ bottom-poured (IGS). One of the IGS heats was calcium-treated to explore the effects of inclusion shape control (IGS/SC). All heats were hot-rolled and reduced over 95 pct to produce bar stock of 127 to 152 mm (5 to 6 in.) in diameter. Transverse axial specimens conforming to ASTM E466 were machined, quenched, and tempered to approximately 40 HRC, and they were fatigue tested in tension-tension cycling ( R = 0.1). Test results and statistical analyses of the stress-life data show that the IGS grade has several times the fatigue strength of the CC grade at 107 cycles. Lower-limit fatigue strengths calculated at a 99.9 pct probability were 518.5 MPa (75.2 ksi) for IGS vs 55.6 MPa (8.1 ksi) for the CC grade. The IGS/SC grade had the best performance at all stress and life levels. The results obtained indicate that fatigue performance can be improved by choosing a processing method that reduces the incidence of exogenous oxides and by controlling the shape of the sulfides.

  4. Nutrient removal and phosphorus recovery performances of a novel anaerobic-anoxic/nitrifying/induced crystallization process.

    Science.gov (United States)

    Shi, Jing; Lu, Xiwu; Yu, Ran; Zhu, Wentao

    2012-10-01

    An anaerobic-anoxic/nitrifying (A(2)N) two sludge process coupled with induced crystallization (IC) called A(2)N-IC process was developed for wastewater nutrient removal and phosphorus recovery. The performances of A(2)N-IC process in comparison with A(2)N process at different COD to phosphorus (COD/P) feeding ratios were investigated. The results indicated that A(2)N-IC achieved not only high and stable nutrient removal but also phosphorus recovery. Calcium phosphorus crystals were formed in the crystallization reactor in A(2)N-IC. Moreover, the incorporation of chemical induced crystallization improved biological phosphorus removal. In A(2)N-IC process, phosphorus removal efficiency was consistently maintained at 99.2%, whereas in A(2)N it decreased from 93.0% to 65.7% with the decrease of feeding COD/P ratio. The COD and ammonia removal efficiencies were regardless of feeding COD/P ratio in the two processes. PMID:22858484

  5. Effets de la marée noire de l' ''Amoco Cadiz '' sur le benthos sublittoral du nord de la Bretagne

    Science.gov (United States)

    Cabioch, L.; Dauvin, J. C.; Mora Bermudez, J.; Rodriguez Babio, C.

    1980-03-01

    Effects of the “Amoco Cadiz ” oil spill on the sublittoral benthos, north of Brittany. Effects of hydrocarbons on the sublittoral macrobenthic communities have been observed through (1) studies of population dynamics of selected communities, conducted prior to the spill by the tanker “Amoco Cadiz ” in spring 1978 and (2) comparisons between the situation in summer 1978 with that in earlier years, with continuation of the observations in some selected sites. The effect of the spill has been selective, involving a limited number of species, mainly crustaceans, molluscs and the sand-urchin Echinocardium cordatum. The spill mainly affected communities on fine sediments and, to a lesser degree, those on mixed sediments. Notably, the destruction of the dominant populations of Ampelisca, in areas of fine sands in the Bay of Morlaix, has led to a marked decrease of biomass and production. Moreover, repopulation will be difficult because of the isolation of such communities on the southern side of the English Channel. The effects evolved with time; after a phase of sharp and selective mortality, which did not last more than a few weeks, secondary effects on the recruitment of the remaining species do not seem to have occurred on a large scale. Nevertheless, a proliferation of polychaetes has been noticed.

  6. Reaction Mechanism for m- Xylene Oxidation in the Claus Process by Sulfur Dioxide

    KAUST Repository

    Sinha, Sourab

    2015-09-24

    In the Claus process, the presence of aromatic contaminants such benzene, toluene, and xylenes (BTX), in the H2S feed stream has a detrimental effect on catalytic reactors, where BTX form soot particles and clog and deactivate the catalysts. Among BTX, xylenes are proven to be most damaging contaminant for catalysts. BTX oxidation in the Claus furnace, before they enter catalyst beds, provides a solution to this problem. A reaction kinetics study on m-xylene oxidation by SO2, an oxidant present in Claus furnace, is presented. The density functional theory is used to study the formation of m-xylene radicals (3-methylbenzyl, 2,6-dimethylphenyl, 2,4-dimethylphenyl, and 3,5-dimethylphenyl) through H-abstraction and their oxidation by SO2. The mechanism begins with SO2 addition on the radicals through an O-atom rather than the S-atom with the release of 180.0-183.1 kJ/mol of reaction energies. This exothermic reaction involves energy barriers in the range 3.9-5.2 kJ/mol for several m-xylene radicals. Thereafter, O-S bond scission takes place to release SO, and the O-atom remaining on aromatics leads to CO formation. Among four m-xylene radicals, the resonantly stabilized 3-methylbenzyl exhibited the lowest SO2 addition and SO elimination rates. The reaction rate constants are provided to facilitate Claus process simulations to find conditions suitable for BTX oxidation. © 2015 American Chemical Society.

  7. An approach to determining the economic feasibility of refuse-derived fuel and materials recovery processing

    Science.gov (United States)

    Gershman, H. W.

    1980-06-01

    An approach for determining the economic feasibility of refuse-derived fuel production and the recovery of materials is presented. This information is based on data developed for the metropolitan Washington, D.C. area as input for the consideration of a regional resource recovery program which would eventually encompass 4000 t/day of municipal solid waste; it is designed to recover refuse-derived fuel (RDF), ferrous and nonferrous metals, flint and color-mixed glass cullet, color-mixed glass fines, and waste newspapers. The planning process requires estimates of recovery product revenues and of process feasibility; since materials revenues can be predicted with a greater degree of certainty than RDF revenues, it becomes necessary to determine what revenues will be required from the sale of RDF so that predicted economics can be the same as the alternative disposal practice. A technique is described which will assist the decisionmaker in evaluating the economic feasibility of the proposed project by determining the RDF 'Indifference Value'.

  8. Heat Transfer Characteristics of Calcined Petroleum Coke in Waste Heat Recovery Process

    Directory of Open Access Journals (Sweden)

    Bin Zheng

    2016-01-01

    Full Text Available This paper reports the results of heat transfer characteristics of calcined petroleum coke in waste heat recovery process. The model of heat exchanger was set up. The model has been used to investigate the effects of porosity (0.58 to 0.79, equivalent heat conductivity coefficient (0.9 to 1.1, and equivalent specific heat (0.9 to 1.1. The calculated values of calcined petroleum coke temperature showed good agreement with the corresponding available experimental data. The temperature distribution of calcined petroleum coke, the calcined petroleum coke temperature at heat exchanger outlet, the average heat transfer coefficient, and the heat recovery efficiency were studied. It can also be used in deriving much needed data for heat exchanger designs when employed in industry.

  9. EXPERIMENTAL STUDY OF DESULFURIZATION OF ZHONG LIANG SHAN HIGH SULFUR COAL BY FLOTATION

    Institute of Scientific and Technical Information of China (English)

    姜志伟; 黄波; 曹炅

    1994-01-01

    Emission of large amount of SO2 from combustion of high sulfur coal causes serious envjsonmental pollution. Pre-combustion desulfurization of bigh sulfur coal has become a necessity. This paper reports test results of fine coal desuifurtzation with different flotation technology and the effect of pyrite depressant. Test work showed that when the coal sample from Zhong Liang Shah was processed with a Free Jet Flotation Column its pyritic sultur content was reduced from 3.08% to 0. 84%, with 72.22% recovery ofcombustible matter in clean coal. The concept of Desulfurlzatlon Efficiency Index Eofor comprehensive evaluation of dcsuifurlzation process is proposed, which is defined as the product of the ratio of sulfur content reduction of clean coal and the recovery of combustible matters.

  10. Selective recovery of gold from waste mobile phone PCBs by hydrometallurgical process

    International Nuclear Information System (INIS)

    Highlights: ► Selective leaching of Au from scrap mobile phone PCBs by two stage electro-generated chlorine and recovery by ion exchange. ► Copper leaching (97%) by 1st stage electro-generated leaching (ORP value Ag/AgCl) with a minor gold (5%). ► Gold leaching (93%, ∼67 mg/L) by 2nd leaching (ORP value >1100 mVAg/AgCl) in 0.1 mol/L HCl at 25 °C. ► A concentrated gold solution, 6034 mg/L with 99.9% purity was obtained by ion exchange process. - Abstract: The leaching of gold from the scrap mobile phone PCBs by electro-generated chlorine as an oxidant and its recovery by ion exchange process was investigated. The leaching experiments were carried out by employing separate leaching reactor connected with the anode compartment of a Cl2 gas generator. The leaching of gold increased with increase in temperature and initial concentration of chlorine, and was favorable even at low concentration of acid, whereas copper leaching increased with increase in concentration of acid and decrease in temperature. In a two-stage leaching process, copper was mostly dissolved (97%) in 165 min at 25 °C during the 1st stage leaching in 2.0 mol/L HCl by electro-generated chlorine at a current density of 714 A/m2 along with a minor recovery of gold (5%). In the 2nd stage gold was mostly leached out (93% recovery, ∼67 mg/L) from the residue of the 1st stage by the electro-generated chlorine in 0.1 mol/L HCl. Gold recovery from the leach liquor by ion exchange using Amberlite XAD-7HP resin was found to be 95% with the maximum amount of gold adsorbed as 46.03 mg/g resin. A concentrated gold solution, 6034 mg/L with 99.9% purity was obtained in the ion exchange process.

  11. Converting the Caetité Mill Process to Enhance Uranium Recovery and Expand Production

    International Nuclear Information System (INIS)

    The Caetité uranium mill was commissioned in 2000 to produce about 340 t U per year from an uranium ore averaging 0.29% U3O8. This production is sufficient to supply the two operating nuclear power plants in the country. As the Brazilian government has recently confirmed its plan to start building another ones from 2009, the uranium production will have to expand its capacity in the next two years. This paper describes the changes in the milling process that are being evaluated in order to not only increase the production but also the uranium recovery, to fulfil the increasing local demand. The heap leaching process will be changed to conventional tank agitated leaching of ground ore slurry in sulphuric acid medium. Batch and pilot plant essays have shown that the uranium recovery can increase from the 77% historical average to about 93%. As the use of sodium chloride as the stripping agent has presented detrimental effects in the extraction and stripping process, two alternatives are being evaluated for the uranium recovery from the PLS: (a) uranium peroxide precipitation at controlled pH from a PLS that was firstly neutralized and filtered. Batch essays have shown good results with a final calcined precipitate averaging 99% U3O8. Conversely the results obtained at the first pilot plant essay has shown that the precipitation conditions of the continuous process calls for further evaluation. The pilot plant is being improved and another essay will be carried out. (b) uranium extraction with a tertiary amine followed by stripping with concentrated sulphuric acid solution. Efforts are being made to recover the excess sulphuric acid from the pregnant stripping solution to enhance the economic viability of the process and to avoid the formation of a large quantity of gypsum in the pre-neutralization step before the uranium peroxide precipitation. (author)

  12. Benzene destruction in claus process by sulfur dioxide: A reaction kinetics study

    KAUST Repository

    Sinha, Sourab

    2014-07-02

    Benzene, toluene and xylene (BTX) are present as contaminants in the H 2S gas stream entering a Claus furnace. The exhaust gases from the furnace enter catalytic units, where BTX form soot particles. These particles clog and deactivate the catalysts. A solution to this problem is BTX oxidation before the gases enter catalyst beds. This work presents a theoretical investigation on benzene oxidation by SO2. Density functional theory is used to develop a detailed mechanism for phenyl radical -SO2 interactions. The mechanism begins with SO2 addition to phenyl radical after overcoming an energy barrier of 6.4 kJ/mol. This addition reaction is highly exothermic, where a reaction energy of 182 kJ/mol is released. The most favorable pathway involves O-S bond breakage, leading to the release of SO. A remarkable similarity between the pathways for phenyl radical oxidation by O2 and its oxidation by SO2 is observed. The reaction rate constants are also evaluated to facilitate process simulations. © 2014 American Chemical Society.

  13. Visualization of the functional recovery process of brain and spinal cord after injury

    International Nuclear Information System (INIS)

    Elucidation of the process of spontaneous functional recovery of central nervous system (CNS) after injury like trauma and stroke is important to develop and conduct the better rehabilitation training to promote the recuperation. Authors have developed a macaque monkey model with an artificial injury of cervical corticospinal tract (CST), where its elaborative motor activity of fingers spontaneously recovers. This paper describes the selective CST injury procedure, its recovery process in finger movement and in CNS images by positron emission tomography (PET), and validation of the obtained images by nerve block. For the injury, CST is cut selectively at monkey's C4/C5 boundary to block the hand motion nerve and to preserve the 2-synapse pathway through the propriospinal neuron, which results in acute loss of grasping a piece of potato food. At 1-3 months after the treatment, the elaborative motor activity of fingers completely recovers. During this recovery period, PET is conducted to trace the brain blood flow change at the upper center of the motion in realizing/grasping food, where the dorsal pathway and cerebellar nuclei are activated at the motion in the untreated animal. At 1-2 months after operation, the blood flow is found increased in the two areas above and the increased area, widened relative to those before operation. At 3 months (at complete functional recovery), the activity in the ipsilateral primary motor area returns to normal level and in the contralateral area, is spread accompanying the increase in the bilateral dorsal premotor and secondary somatosensory areas. Imaging results are validated by nerve block with micro-injection of muscimol into the activated areas during the task motor. Findings are helpful for developing a method to promote the compensation of nervous function after injury. (K.T.)

  14. Study on the Recovery of Rhodium from Spent Organic Rhodium Catalysts of Acetic Acid Industry Using Pyrometallurgical Process

    Institute of Scientific and Technical Information of China (English)

    HE Xiaotang; WANG Huan; WU Xilong; LI Yong; ZHAO Yu; HAN Shouli; LI Kun; GUO Junmei

    2012-01-01

    A new process recycling rhodium from organic waste containing rhodium in acetic acid industry is developed.Use the special affinity of base metal sulfides (FeS,Ni2S3,CuS,etc.) on platinum group metals,adopting high nickel matte trapping-aluminothermic activation method to recovery rhodium from incinerator residue of organic rhodium waste.The method is shorter process,lower equipment requirement,and the higher activity of rhodium black.In pyrometallurgy enrichment process,the recovery rate of rhodium reached 94.65%,the full flow of rhodium recovery rate was 92.04%.

  15. Supporting technology for enhanced oil recovery: EOR thermal processes. Seventh Amendment and Extension to Annex 4, Enhanced oil recovery thermal processes

    Energy Technology Data Exchange (ETDEWEB)

    Reid, T B [USDOE Bartlesville Project Office, OK (United States); Colonomos, P [INTEVEP, Filial de Petroleos de Venezuela, SA, Caracas (Venezuela)

    1993-02-01

    This report contains the results of efforts under the six tasks of the Seventh Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections (for each of the 6 tasks) and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section. The tasks are numbered 50 through 55. The first, second, third, fourth, fifth, sixth and seventh reports on Annex IV, Venezuela MEM/USA-DOE Fossil Energy Report IV-1, IV-2, IV-3, IV-4, IV-5 and IV-6 (DOE/BETC/SP-83/15, DOE/BC-84/6/SP, DOE/BC-86/2/SP, DOE/BC-87/2/SP, DOE/BC-89/l/SP, DOE/BC-90/l/SP, and DOE/BC-92/l/SP) contain the results for the first 49 tasks. Those reports are dated April 1983, August 1984, March 1986, July 1987, November 1988, December 1989, and October 1991, respectively. Each task report has been processed separately for inclusion in the Energy Science and Technology Database.

  16. Improvement of gaseous energy recovery from sugarcane bagasse by dark fermentation followed by biomethanation process.

    Science.gov (United States)

    Kumari, Sinu; Das, Debabrata

    2015-10-01

    The aim of the present study was to enhance the gaseous energy recovery from sugarcane bagasse. The two stage (biohydrogen and biomethanation) batch process was considered under mesophilic condition. Alkali pretreatment (ALP) was used to remove lignin from sugarcane bagasse. This enhanced the enzymatic digestibility of bagasse to a great extent. The maximum lignin removal of 60% w/w was achieved at 0.25 N NaOH concentration (50°C, 30 min). The enzymatic hydrolysis efficiency was increased to about 2.6-folds with alkali pretreated sugarcane bagasse as compared to untreated one. The maximum hydrogen and methane yields from the treated sugarcane bagasse by biohydrogen and biomethanation processes were 93.4 mL/g-VS and 221.8 mL/g-VS respectively. This process resulted in significant increase in energy conversion efficiency (44.8%) as compared to single stage hydrogen production process (5.4%). PMID:26210150

  17. Opportunities for low-grade heat recovery in the UK food processing industry

    International Nuclear Information System (INIS)

    Energy efficiency in the process industry is becoming an increasingly important issue due to the rising costs of both electricity and fossil fuel resources, as well as the tough targets for the reduction in greenhouse gas emissions outlined in the Climate Change Act 2008. Utilisation of waste heat sources is key to improving industrial energy efficiency, with an estimated 11.4 TWh of recoverable heat being wasted each year, a quarter of which is from the food and drinks processing sector. This paper examines the low-grade waste heat sources common to the food and drinks processing sector and the various opportunities for the use of this heat. A review of the best available technologies for recovery of waste heat is provided, ranging from heat transfer between source and sink, to novel technologies for the generation of electricity and refrigeration. Generally, the most economic option for waste heat recovery is heat exchange between nearby/same process source and sink, with a number of well-developed heat exchangers widely available for purchase. More novel options, such as the use of organic Rankine cycles for electricity generation prove to be less economical due to high capital outlays. However, with additional funding provision for demonstration of such projects and development of modular units, such technologies would become more common

  18. ThermoEnergy Ammonia Recovery Process for Municipal and Agricultural Wastes

    Directory of Open Access Journals (Sweden)

    Alex G. Fassbender

    2001-01-01

    Full Text Available The Ammonia Recovery Process (ARP is an award-winning, low-cost, environmentally responsible method of recovering nitrogen, in the form of ammonia, from various dilute waste streams and converting it into concentrated ammonium sulfate. The ThermoEnergy Biogas System utilizes the new chemisorption-based ARP to recover ammonia from anaerobically digested wastes. The process provides for optimal biogas production and significantly reduced nitrogen levels in the treated water discharge. Process flows for the ammonia recovery and ThermoEnergy biogas processes are presented and discussed. A comparison with other techniques such as biological nitrogen removal is made. The ARP technology uses reversible chemisorption and double salt crystal precipitation to recover and concentrate the ammonia. The ARP technology was successfully proven in a recent large-scale field demonstration at New York City’s Oakwood Beach Wastewater Treatment Plant, located on Staten Island. This project was a joint effort with Foster Wheeler Environmental Corporation, the Civil Engineering Research Foundation, and New York City Department of Environmental Protection. Independent validated plant data show that ARP consistently recovers up to 99.9% of the ammonia from the city’s centrate waste stream (derived from dewatering of sewage sludge, as ammonium sulfate. ARP technology can reduce the nitrogen (ammonia discharged daily into local bodies of water by municipalities, concentrated animal farming operations, and industry. Recent advances to ARP enhance its performance and economic competitiveness in comparison to stripping or ammonia destruction technologies.

  19. SELECTIVE SEPARATION AND RECOVERY PROCESS —Supercritical fluid extraction and fractionation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A selective separation and recovery process has been developed based on the supercritical fluid extraction and fractionation (SFEF) technology. The solvent used varies from C3 to C5, depending on process objective. Basic research work has been done on the phase behavior, phase equilibria and modeling of a number of systems including petroleum residue, polymers, waxes and lubricants with the light hydrocarbon solvents. Semi-batch pilot and continuous pilot experiments were performed to establish data base for the process design of industrial scale. The effects of operation para-meters, such as temperature, pressure, ratio of solvent to oil and residence time, on separation selectivity and yield of extracts were studied in a wide range. Industrial demonstration plant with a capacity of 15 kt/a was setup and has run for a sufficient long period of time to confirm the design and to obtain the energy cost and economic analysis data for further commercial scale up. It was found that the process offers high efficient products and solvent recovery.

  20. Richness and species composition of ants in the recovery process of a gully erosion

    Directory of Open Access Journals (Sweden)

    Gabriel Biagiotti

    2013-12-01

    Full Text Available This study aimed to determine how the richness and composition of ant species behaves with changes in the recovery process of a gully erosion. The study area has 0.9 hectares subdivided into three sections called sector: "A", "B" and "C". For the definition of the sectors, erosive and natural restoring were taken as the base level of activity. Four transects were laid systematically throughout the area and surrounding compound with forest and grassland. Each transect had three "pitfall trap" ten meters apart from each other, with catches of ants were held in rainy and dry seasons. Analysis of variance was applied to compare the number of ant species per plot captured and Scott-Knott test 5% for comparison of means. To verify the similarity of species between environments it was performed an analysis of similarity (ANOSIM and ordering of environments a "Nonmetric Multidimensional Scaling" (NMDS. We captured 74 species of ants inside and around the gully erosion. The more degraded environment and initial stage of regeneration, showed greater richness of ant species. The composition of ant species was different between the recovery environments and around. The parameters of ant communities analyzed, richness and composition species were influenced by the regeneration of the area, indicating that ants can be used as bioindicators of gullies recovery.

  1. Developments in gold and silver recovery through flotation in processing of gold ore slags

    International Nuclear Information System (INIS)

    The aim of this work is to recover and improve the extraction of gold and silver present in smelting slags through various mineralogical processes applicable in gold ores. The slag was concentrated in a Knelson type centrifuge, two concentrates (C1 and C2 and a tailing T1) being obtained. In order to improve the recovery, three series of rougher flotation tests were conducted on the tailing T1. The variables analyzed were: particle size, type of collectors (xanthates, di-monothiophosphate) and flotation time. It was deduced that by applying gravity concentration, the recovery of Au and Ag (Knelson centrifuge) is 42.0% and 13.7%, respectively. Au recovery is improved by 87.7% through the flotation of the centrifuge separation tailings, whereas that for Ag is 47.4%. The optimum conditions were: particle size 200 mesh, collectors: PAX (15.8 g/t), F-C5439 (18.75 g/t), MIBC frother (12.5g/t) and 8.5 minutes of flotation time. (Author)

  2. Recovery of manganese and zinc from spent Zn-C cell powder: Experimental design of leaching by sulfuric acid solution containing glucose.

    Science.gov (United States)

    Biswas, Ranjit K; Karmakar, Aneek K; Kumar, Sree L

    2016-05-01

    The spent Zn-C cell powder, containing ZnMn2O4, ZnO, MnO(OH) and possibly Mn2O3 and Mn3O4, can be leached by a sulfuric acid solution mixed with some glucose. The leaching is found to be dependent on solid to liquid (S/L) ratio, amount of glucose, concentration of sulfuric acid solution, time and pulp agitation speed. For 5g powder (S), 1h leaching time and 300rpm pulp agitation speed, two-level four-factor (2(4)) experimental designs have been carried out to derive models for extraction of both Mn(II) and Zn(II). Amount of glucose (G, g), concentration of H2SO4 solution (C, mol/L), volume of H2SO4 solution as leachant (L, mL) and leaching temperature (T, °C) are considered as factors (variables). The model in both cases consists of mean, factor effects and interaction effects. The four-factor interaction effect is observed in neither of the cases. Some two-factor and three-factor effects are found to have produced positive or negative contributions to dissolution percentage in both cases. The models are examined for comparison with experimental results with good fits and also used for optimization of factors. At optimized condition (G=0.50g, C=2mol/L, L=250mL and T=100°C), an aliquot of 5g powder in 1h and at 300rpm produces a solution containing (7.08±0.10)g/L Mn(II) and (2.20±0.06)g/L Zn(II) corresponding to almost 100% extraction of both metal ions. PMID:26564257

  3. Development of lysozyme-combined antibacterial system to reduce sulfur dioxide and to stabilize Italian Riesling ice wine during aging process

    OpenAIRE

    Chen, Kai; Han, Shun-yu; Zhang, Bo; Li, Min; Sheng, Wen-jun

    2015-01-01

    For the purpose of SO2 reduction and stabilizing ice wine, a new antibacterial technique was developed and verified in order to reduce the content of sulfur dioxide (SO2) and simultaneously maintain protein stability during ice wine aging process. Hazardous bacterial strain (lactic acid bacteria, LAB) and protein stability of Italian Riesling ice wine were evaluated in terms of different amounts of lysozyme, SO2, polyphenols, and wine pH by single-factor experiments. Subsequently, a quadratic...

  4. Petrographic and isotopic evidence for late-stage processes in sulfuric acid caves of the Guadalupe Mountains, New Mexico, USA

    Directory of Open Access Journals (Sweden)

    Palmer Arthur N.

    2012-07-01

    Full Text Available Caves of the Guadalupe Mountains have experienced many modifications since their final phase of sulfuric acid speleogenesis several million years ago. Petrographic and geochemical data reveal details of the change from H2SO4 to CO2-dominated reactions. The H2SO4 dissolution front acquired a coating of replacement gypsum with local pockets of anhydrite and by-products of altered clay, including Fe-Mn oxides. Alteration of bedrock beneath the gypsum produced a white micritized rind with small negative shifts in δ13C and δ18O. Solution basins contain records of the earliest post-speleogenetic processes: corroded bedrock, residual anhydrite, Fe-Mn oxides from fluctuating pH and Eh, mammillary calcite, and dolomitization. Later meteoric water removed or recrystallized much of the gypsum and early micrite, and replaced some gypsum with calcite. Mammillary crusts demonstrate fluctuating groundwater, with calcite layers interrupted by films of Fe-Mn oxides precipitated during periodic inflow of anoxic water. Condensation moisture (from local evaporation absorbs CO2 from cave air, corroding earlier features and lowering their δ13C and δ18O. Drips of condensation water deposit minerals mainly by evaporation, which increases δ18O in the speleothems while δ13C remains nearly constant. By forcing calcite precipitation, evaporation raises the Mg content of remaining water and subsequent precipitates. Dolomite (both primary and replacive is abundant. In areas of low air circulation, water on and within carbonate speleothems equilibrates with cave-air CO2, causing minerals to recrystallize with glassy textures. Fluorite on young evaporative speleothems suggests a recent release of deep-source HF gas and absorption by droplets of condensation water.

  5. Granulation of susceptible sludge under carbon deficient conditions: A case of denitrifying sulfur conversion-associated EBPR process.

    Science.gov (United States)

    Guo, Gang; Wu, Di; Hao, Tianwei; Mackey, Hamish Robert; Wei, Li; Lu, Hui; Chen, Guanghao

    2016-10-15

    Sludge granulation has been recognized as a promising biotechnology in wastewater treatment. Whereas the granulation of susceptible sludge in particular with a very low organic loading rate (OLR) (≤0.6 kg COD/m(3)/day or ≤ 120 mg COD/g VSS/day) is a difficult task that has not been achieved in activated sludge systems yet. This study was aimed at exploring an effective strategy for sludge granulation in the recently developed Denitrifying Sulfur conversion-associated Enhanced Biological Phosphorus Removal (DS-EBPR) process using a sequencing batch pump-lift reactor. Four strategies were studied by manipulating the factors of organic loading rate (OLR), superficial upflow velocity and sludge settling time individually or collectively. Increasing both the OLR and the superficial upflow velocity effectively promoted granule formation but at the same time led to unstable and even deteriorated reactor performance. The development of granules proceeded via several stages: formation, dispersion, reformation and stabilization. Gradually increasing the superficial upflow velocity from 5.1 to 6.8 m/h and keeping the OLR at 112.4 mg COD/g VSS/day proved to be most effective strategy for accelerating granulation while simultaneously achieving stable reactor performance. Under these conditions, the granules became stable with a diameter of 375-400 μm and displayed excellent settleability. The two major microbial groups, sulfate-reducing bacteria and sulfide-oxidizing bacteria, in the microbial community of the DS-EBPR granular sludge were enriched to 17.7% and 15.8% respectively. The newly developed DS-EBPR granular system was able to achieve an almost threefold improvement in phosphorus removal efficiency and 25% reduction in the operating cycle time compared with a flocculent DS-EBPR system. PMID:27498252

  6. Influence of Sulfur Fertilization on the Antioxidant Activities of Onion Juices Prepared by Thermal Treatment

    OpenAIRE

    Koh, Eunmi; Surh, Jeonghee

    2016-01-01

    Two onions (Sulfur-1 and Sulfur-4) cultivated with different sulfur applications were thermally processed to elucidate the effects of heat treatment on browning index and antioxidant activity. Sulfur-4 onion had higher sulfur content compared with the Sulfur-1 onion. After thermal processing, browning intensity was different between the two onions juices, with lower values observed for Sulfur-4 onion juice. This suggests that sulfur inhibits the Maillard browning reaction. The total reducing ...

  7. The Role of Attrition and Solids Recovery in a Chemical Looping Combustion Process

    International Nuclear Information System (INIS)

    In the present work, the steady-state behavior of a Chemical Looping Combustion process of interconnected fluidized bed reactors is simulated. The simulations have been carried out in two different scales, 50 kWth and 100 MWth. Attrition model derived from small scale laboratory experiments has been employed for the prediction of the process behavior in terms of attrition and Oxygen Carrier loss. Information on Oxygen Carrier characteristics and reaction kinetics were taken from literature. Realistic circulation mass flows of Oxygen Carrier particles are obtained and Oxygen Carrier losses are quantified. The large scale process looses significantly more Oxygen Carrier than the small scale process based on the same amount of thermal energy produced. Incomplete conversion in the air reactor could be identified as a critical point. Another issue is the fuel gas bypassing the Oxygen Carrier particles through bubbles in the large scale process which leads to lowered fuel conversions. The simulations indicate that a similar performance of a pilot scale and a large scale process is not guaranteed due to the scale-up effect on fluid dynamics. Furthermore, the simulations allow an assessment of the influence of the quality of the solids recovery system on the Oxygen Carrier loss. The distribution of the losses between possible origins is investigated and different changes in the solids recovery system are discussed regarding their potential to decrease the Oxygen Carrier loss. For example, the addition of a second-stage cyclone after the air reactor of the large scale process reduces the Oxygen Carrier loss significantly. (authors)

  8. Zero-discharge: An application of process water recovery technology in the food processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Fok, S.; Moore, B.

    1999-07-01

    Water is a valuable natural resource and the food processing industry has been among the leading industrial water users in California. With support from a major northern California utility and the California Institute for Food and Agricultural Research, Tri Valley Growers (TVG) has successfully installed the first US energy-efficient zero-discharge process water reclamation system at its Oberti Olive processing facility in Madera, California. The advanced zero-discharge system is the largest application in the world of membrane filtration for recovering water from a food processing plant. Previously, the plant discharged an average of 1 million gallons of salty wastewater (brine) a day into 160 acres of evaporation ponds. However, new environmental regulations made the ponds obsolete. The cost of process water disposal using alternate biotreatment system was prohibitive and would make continued operation uneconomical with plant closure and job loss the likely outcome. Through comprehensive pilot testing and subsequent system design and operational optimization, the advance membrane filtration system with pre- and post-treatment now recovers about 80% of the process liquid in high priority form of water for subsequent reuse at the plant. The solids produced in olive processing, plus concentrated process liquids are used off-site as an animal feed component, thus achieving the plant zero-discharge scheme. The successful implementation of the zero discharge system at the Oberti Olive processing plant has produced energy saving of 3,500,000 kilowatthours and 244,000 therms of gas a year of power as compared to the alternate biotreatment system. It also prevented plant closure and job loss. In addition, water conservation and the discontinuation of evaporation pond use is beneficial to the environment. The project was applauded by the California Environmental Protection Agency as a positive step forward for environmental technology in the agricultural sector in

  9. Experimental Evaluation of Hybrid Distillation-Vapor Permeation Process for Efficient Ethanol Recovery from Ethanol-Water Mixtures

    Science.gov (United States)

    The energy demand of distillation-based systems for ethanol recovery and dehydration can be significant, particularly for dilute solutions [1]. An alternative separation process integrating vapor stripping with a vapor compression step and a vapor permeation membrane separation ...

  10. Heat Transfer Characteristics of Calcined Petroleum Coke in Waste Heat Recovery Process

    OpenAIRE

    Bin Zheng; Yongqi Liu; Lichen Zou; Ruiyang Li

    2016-01-01

    This paper reports the results of heat transfer characteristics of calcined petroleum coke in waste heat recovery process. The model of heat exchanger was set up. The model has been used to investigate the effects of porosity (0.58 to 0.79), equivalent heat conductivity coefficient (0.9 to 1.1), and equivalent specific heat (0.9 to 1.1). The calculated values of calcined petroleum coke temperature showed good agreement with the corresponding available experimental data. The temperature distri...

  11. Conversion of a deasphalting unit for use in the process of supercritical solvent recovery

    Directory of Open Access Journals (Sweden)

    Waintraub S.

    2000-01-01

    Full Text Available In order to reduce energy consumption and to increase deasphalted oil yield, an old PETROBRAS deasphalting unit was converted for use in the process of supercritical solvent recovery. In-plant and pilot tests were performed to determine the ideal solvent-to-oil ratio. The optimum conditions for separation of the supercritical solvent from the solvent-plus-oil liquid mixture were determined by experimental tests in PVT cells. These tests also allowed measurement of the dew and bubble points, determination of the retrograde region, observation of supercritical fluid compressibility and as a result construction of a phase equilibrium diagram.

  12. Distribution ratios on Dowex 50W resins of metal leached in the caron nickel recovery process

    International Nuclear Information System (INIS)

    Pressurized ion exchange on Dowex 50W-X8 and 50W-X12 resins was investigated using elution techniques to determine distribution ratios for copper, nickel, and cobalt complexes contained in ammonium carbonate solution, a mixture which approximates the waste liquor from the Caron nickel recovery process. Results were determined for different feed concentrations, as well as for different concentrations and pH values of the ammonium carbonate eluant. Distribution ratios were compared with those previously obtained from a continuous annular chromatographic system. Separation of copper and nickel was not conclusively observed at any of the conditions examined

  13. Distribution ratios on Dowex 50W resins of metal leached in the caron nickel recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, B.A.; Metsa, J.C.; Mullins, M.E.

    1980-05-01

    Pressurized ion exchange on Dowex 50W-X8 and 50W-X12 resins was investigated using elution techniques to determine distribution ratios for copper, nickel, and cobalt complexes contained in ammonium carbonate solution, a mixture which approximates the waste liquor from the Caron nickel recovery process. Results were determined for different feed concentrations, as well as for different concentrations and pH values of the ammonium carbonate eluant. Distribution ratios were compared with those previously obtained from a continuous annular chromatographic system. Separation of copper and nickel was not conclusively observed at any of the conditions examined.

  14. The Effects of Children on the Process of Recovery in Oxford Houses

    OpenAIRE

    2012-01-01

    The effects of children on the process of substance use recovery for adults living in Oxford Houses is explored in two qualitative studies. Oxford Houses are self-run, community-based residential homes for small groups of adults who live together and support each other’s efforts to recover from drug and/or alcohol addiction. In the first study, telephone interviews were conducted with 29 adults who were living in Oxford Houses that allowed children to live in the house with their parent. Resu...

  15. Solar Energy for a Solvent Recovery Stage in a Biodiesel Production Process

    Directory of Open Access Journals (Sweden)

    José A. León

    2016-01-01

    Full Text Available Recent research and development of clean energy have become essential due to the global climate change problem, which is caused largely by fossil fuels burning. Therefore, biodiesel, a renewable and ecofriendly biofuel with less environmental impact than diesel, continues expanding worldwide. The process for biodiesel production involves a significant energy demand, specifically in the methanol recovery stage through a flash separator and a distillation column. Traditionally, the energy required for this process is supplied by fossil fuels. It represents an opportunity for the application of renewable energy. Hence, the current study presents a system of thermal energy storage modeled in TRNSYS® and supported by simulations performed in ASPEN PLUS®. The aim of this research was to supply solar energy for a methanol recovery stage in a biodiesel production process. The results highlighted that it is feasible to meet 91% of the energy demand with an array of 9 parabolic trough collectors. The array obtained from the simulation was 3 in series and 3 in parallel, with a total area of 118.8 m2. It represents an energy saving of 70 MWh per year.

  16. Recovery of ammonia in digestates of calf manure through a struvite precipitation process using unconventional reagents.

    Science.gov (United States)

    Siciliano, A; De Rosa, S

    2014-01-01

    Land spreading of digestates causes the discharge of large quantities of nutrients into the environment, which contributes to eutrophication and depletion of dissolved oxygen in water bodies. For the removal of ammonia nitrogen, there is increasing interest in the chemical precipitation of struvite, which is a mineral that can be reused as a slow-release fertilizer. However, this process is an expensive treatment of digestate because large amounts of magnesium and phosphorus reagents are required. In this paper, a struvite precipitation-based process is proposed for an efficient recovery of digestate nutrients using low-cost reagents. In particular, seawater bittern, a by-product of marine salt manufacturing and bone meal, a by-product of the thermal treatment of meat waste, have been used as low-cost sources of magnesium and phosphorus, respectively. Once the operating conditions are defined, the process enables the removal of more than 90% ammonia load, the almost complete recovery of magnesium and phosphorus and the production of a potentially valuable precipitate containing struvite crystals. PMID:24645466

  17. Process control and recovery in the Link Monitor and Control Operator Assistant

    Science.gov (United States)

    Lee, Lorrine; Hill, Randall W., Jr.

    1993-01-01

    This paper describes our approach to providing process control and recovery functions in the Link Monitor and Control Operator Assistant (LMCOA). The focus of the LMCOA is to provide semi-automated monitor and control to support station operations in the Deep Space Network. The LMCOA will be demonstrated with precalibration operations for Very Long Baseline Interferometry on a 70-meter antenna. Precalibration, the task of setting up the equipment to support a communications link with a spacecraft, is a manual, time consuming and error-prone process. One problem with the current system is that it does not provide explicit feedback about the effects of control actions. The LMCOA uses a Temporal Dependency Network (TDN) to represent an end-to-end sequence of operational procedures and a Situation Manager (SM) module to provide process control, diagnosis, and recovery functions. The TDN is a directed network representing precedence, parallelism, precondition, and postcondition constraints. The SM maintains an internal model of the expected and actual states of the subsystems in order to determine if each control action executed successfully and to provide feedback to the user. The LMCOA is implemented on a NeXT workstation using Objective C, Interface Builder and the C Language Integrated Production System.

  18. Conformational dynamics of Rouse chains during creep/recovery processes: a review

    International Nuclear Information System (INIS)

    The Rouse model is a well-established model for non-entangled polymer chains and also serves as a fundamental model for entangled chains. The dynamic behaviour of this model under strain-controlled conditions has been fully analysed in the literature. However, despite the importance of the Rouse model, no analysis has been made so far of the orientational anisotropy of the Rouse eigenmodes during the stress-controlled, creep and recovery processes. For completeness of the analysis of the model, the Rouse equation of motion is solved to calculate this anisotropy for monodisperse chains and their binary blends during the creep/recovery processes. The calculation is simple and straightforward, but the result is intriguing in the sense that each Rouse eigenmode during these processes has a distribution in the retardation times. This behaviour, reflecting the interplay/correlation among the Rouse eigenmodes of different orders (and for different chains in the blends) under the constant stress condition, is quite different from the behaviour under rate-controlled flow (where each eigenmode exhibits retardation/relaxation associated with a single characteristic time). Furthermore, the calculation indicates that the Rouse chains exhibit affine deformation on sudden imposition/removal of the stress and the magnitude of this deformation is inversely proportional to the number of bond vectors per chain. In relation to these results, a difference between the creep and relaxation properties is also discussed for chains obeying multiple relaxation mechanisms (Rouse and reptation mechanisms). (topical review)

  19. Removal and recovery of carbon disulfide emitted by the viscose process. Final report

    Energy Technology Data Exchange (ETDEWEB)

    McIntosh, M.J.

    1992-02-01

    Teepak, Inc., which manufactures cellulose food casings by means of the viscose process, has a plant in Danville, Illinois, that emits approximately 400,000 cubic feet per minute (cfm) of water-saturated air containing approximately 100 parts per million (ppm) of carbon disulfide (CS{sub 2}). Both Teepak and the state of Illinois desire to reduce these emissions as soon as possible; however, the large air flow and very small CS{sub 2} concentration result in a difficult and costly separations problem without an obvious economically viable solution. One possibility is to incinerate the CS{sub 2}, but a more environmentally and economically acceptable alternative is to recover the CS{sub 2} for recycle to the process. The recovered CS{sub 2} would be worth about $700,000 annually to Teepak. Teepak has sponsored, with the Hazardous Waste Research and Information Center (HWRIC) of the Illinois Department of Natural Resources, a research project at Argonne National Laboratory (ANL) to evaluate current gas- purification and recovery technology and to suggest a route of development that will lead to a CS{sub 2} recovery process. The Illinois Department of Commerce and Community Affairs later provided on Illinois Challenge Grant to allow laboratory studies to supplement this effort. This report is a result of all those studies.

  20. Removal and recovery of carbon disulfide emitted by the viscose process

    Energy Technology Data Exchange (ETDEWEB)

    McIntosh, M.J.

    1992-02-01

    Teepak, Inc., which manufactures cellulose food casings by means of the viscose process, has a plant in Danville, Illinois, that emits approximately 400,000 cubic feet per minute (cfm) of water-saturated air containing approximately 100 parts per million (ppm) of carbon disulfide (CS{sub 2}). Both Teepak and the state of Illinois desire to reduce these emissions as soon as possible; however, the large air flow and very small CS{sub 2} concentration result in a difficult and costly separations problem without an obvious economically viable solution. One possibility is to incinerate the CS{sub 2}, but a more environmentally and economically acceptable alternative is to recover the CS{sub 2} for recycle to the process. The recovered CS{sub 2} would be worth about $700,000 annually to Teepak. Teepak has sponsored, with the Hazardous Waste Research and Information Center (HWRIC) of the Illinois Department of Natural Resources, a research project at Argonne National Laboratory (ANL) to evaluate current gas- purification and recovery technology and to suggest a route of development that will lead to a CS{sub 2} recovery process. The Illinois Department of Commerce and Community Affairs later provided on Illinois Challenge Grant to allow laboratory studies to supplement this effort. This report is a result of all those studies.

  1. Flowsheet study of HI separation process from HI-H2O-I2 solution in the thermochemical hydrogen production iodine-sulfur (IS) process

    International Nuclear Information System (INIS)

    Heat demand was investigated by flowsheet calculation of the subsection of HI separation from HI-H2O-I2 solution in the thermochemical hydrogen production iodine-sulfur (IS) process. Concentration of HI by electro-electrodialysis (EED) and conventional distillation of HI were applied to the subsection. Heat/mass balance of HI distillation column was calculated using the Environmental Simulation Program (ESP), a process simulation software. Experimental data of Nafion® 117 cation exchange membrane, including upper limit of HI molality difference between outlet streams, was applied for the EED cell modeling. HI molality at the cathode outlet of the cell, pressure in the HI distillation column, and flow rate ratio of the feed to the subsection to distillate of the column were focused on as variable parameters. Optimum EED HI molality to minimize the heat demand of the subsection appeared because the tendency of the advantageous HI molality was different for the cell and the column. Though the minimum heat demand decreased as the increase of the column pressure, the demands at 1.0 MPa and at 2.0 MPa were similar. Though total heat demand was small in smaller flow rate ratio, the ratio had an attainable lower limit. The heat/mass balance of the subsection with the optimized parameters, which was more realistic than our previous analysis, was shown. (author)

  2. Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery

    International Nuclear Information System (INIS)

    Lawrence Livermore National Laboratory participated in a U. S. Department of Energy/Office of Industrial Technology sponsored research project 'Development of a Rolling Process Design Tool for Use in Improving Hot Roll Slab Recovery', as a Cooperative Agreement TC-02028 with the Alcoa Technical Center (ATC). The objective of the joint project with Alcoa is to develop a numerical modeling capability to optimize the hot rolling process used to produce aluminum plate. Product lost in the rolling process and subsequent recycling, wastes resources consumed in the energy-intensive steps of remelting and reprocessing the ingot. The modeling capability developed by project partners will be used to produce plate more efficiently and with reduced product loss

  3. Phosphorus Recovery from a Water Reservoir–Potential of Nanofiltration Coupled to Electrodialytic Process

    DEFF Research Database (Denmark)

    Couto, N.; Guedes, P.; Mateus, E. P.;

    2013-01-01

    Worldwide waste streams can represent an environmental problem if they are considered “deleterious material”. These streams may also be a source of secondary resources when enclosing compounds with potential to be recovered. Phosphorus (P) is one of those, with an increasing interest, as it is...... essential for life but its non-renewable reserves are expected to last about one century. Nanofiltration (NF) and electrodialytic process (ED) were applied to a stream from a Water Treatment Plant (WTP). Water from Funcho Dam Reservoir, Portugal, was subject of NF treatment followed by ED process for P...... recovery. The feed concentration of P for ED process was between 1,429 and 1,845 μg/L. Optimization studies were carried out in laboratory cells. Almost complete P removal out of the central compartment of the ED cell was observed under the action of an applied electric field. Experiments lasted between ca...

  4. 硫精矿除杂提纯浮选工艺回收利用硫酸烧渣中的铁%Iron recovery from pyrite cinder by flotation process to remove impurities in sulfide concentrates

    Institute of Scientific and Technical Information of China (English)

    冯国臣; 高金昌

    2015-01-01

    硫酸烧渣是硫铁矿制酸氧化焙烧产物;从硫酸烧渣中选铁的工艺技术指标一直不高,其主要原因是硫铁矿氧化焙烧过程中生成的氧化铁矿物颗粒微细,高温时新生成的氧化铁矿物颗粒会与杂质和脉石矿物颗粒相互包裹、相互黏结、相互污染. 该文将硫酸烧渣选铁改为硫精矿再浮选提纯硫化铁,即通过提纯硫酸原料中硫化铁的质量分数,从而去除原料中的脉石和杂质,使硫酸原料中硫品位达到50 % ~52 %(黄铁矿型原料)以上,硫、铁回收率均达到90 % ~92 %;采用该高纯硫精矿制造硫酸,硫酸烧渣中铁品位达到63 % ~67 %,使硫酸烧渣全部直接成为铁精矿,无需再选矿,达到了有效利用硫酸烧渣中铁的目的. 该工艺能够获得较高技术指标的原因是硫精矿除杂提纯浮选是硫化矿选硫,采用高纯硫精矿制酸,避免了非目的矿物污染硫化铁的氧化焙烧过程以及硫酸烧渣选铁时杂质含量高、铁品位低、选矿技术指标低等问题.%Pyrite cinder is the product of oxidizing roasting of pyrite ores. The technical index in iron recovery from pyrite cinder keeps low. The main reason for it is that fine ferric oxide particles produced in the oxidizing roasting process of pyrite ores will in high temperature interact with impurities and gangue minerals including mutual inclu-ding,sticking and polluting. The paper modifies conventional process of iron recovery from pyrite cinder,and turns to a sulfide concentrates flotation process to concentrate ferric sulfide,that is to increase the mass fraction of ferric sulfide in raw materials of pyrites,so that gangue minerals and impurities are removed from the raw materials,reaching a sul-fur grade over 50 % to 52 % and sulfur and iron grade of 90 % to 92 %. The high grade sulfur concentrates are used to made sulfuric acid. The iron in pyrite cinder reaches 63 % to 67 % making the entire cinder directly become iron concentrates

  5. Sequential process for extraction and recovery of vanadium and uranium from wet process acids

    International Nuclear Information System (INIS)

    A process for preferentially extracting and recovering vanadium and uranium from wet process acids is claimed. The wet process acid first is contacted with a neutral organophosphorus compound to extract the vanadium values. The resulting loaded organic phase is separated from the wet process acid due to immiscibility of the acid and organic phases. The vanadium values then are separated from the organic phase by stripping. The raffinate separated from the first organic extractant then is contacted with a second organic extractant comprising a dialkyl-phosphoric acid and a neutral organo-phosphorus compound to extract the uranium values. The resulting loaded organic phase is separated from the wet process acid due to immiscibility of the acid and organic phases. The organic phase is stripped with a reductive stripping solution and the stripping solution then is oxidized to convert the uranium values to the hexavalent oxidation state. The oxidized solution then is contacted with another organic extractant to reextract the uranium to thereby concentrate the uranium product which then is stripped from the organic product with ammonium carbonate to form ammonium uranyl carbonate

  6. RO brine treatment and recovery by biological activated carbon and capacitive deionization process.

    Science.gov (United States)

    Tao, Guihe; Viswanath, Bala; Kekre, Kiran; Lee, Lai Yoke; Ng, How Yong; Ong, Say Leong; Seah, Harry

    2011-01-01

    The generation of brine solutions from dense membrane (reverse osmosis, RO or nanofiltration, NF) water reclamation systems has been increasing worldwide, and the lack of cost effective disposal options is becoming a critical water resources management issue. In Singapore, NEWater is the product of a multiple barrier water reclamation process from secondary treated domestic effluent using MF/UF-RO and UV technologies. The RO brine (concentrates) accounts for more than 20% of the total flow treated. To increase the water recovery and treat the RO brine, a CDI based process with BAC as pretreatment was tested. The results show that ion concentrations in CDI product were low except SiO2 when compared with RO feed water. CDI product was passed through a RO and the RO permeate was of better quality including low SiO2 as compared to NEWater quality. It could be beneficial to use a dedicated RO operated at optimum conditions with better performance to recover the water. BAC was able to achieve 15-27% TOC removal of RO brine. CDI had been tested at a water recovery ranging from 71.6 to 92.3%. CDI based RO brine treatment could improve overall water recovery of NEWater production over 90%. It was found that calcium phosphate scaling and organic fouling was the major cause of CDI pressure increase. Ozone disinfection and sodium bisulfite dosing were able to reduce CDI fouling rate. For sustainable operation of CDI organic fouling control and effective organic fouling cleaning should be further studied. PMID:22053461

  7. Overview of Membrane Processes for the Recovery of Polyphenols from Olive Mill Wastewater

    Directory of Open Access Journals (Sweden)

    Ompe Aime Mudimu

    2012-01-01

    Full Text Available Problem statement: Olive Mill Wastewater (OMW is an ambivalent by-product of the olive oil production, which appears in huge amounts every year after the olive-harvest in the production countries, mainly in the Mediterranean region. OMW is characterized by a high organic load and i.a. contains considerable amounts of phytotoxical polyphenols, which cause important environmental problems. Approach: Due to their antioxidant properties the use of these polyphenols is also popular in several industry branches, which results in high sale values for this group of chemicals. The removal of polyphenols from biological wastewaters like OMW does not only reduce the pollutant load but also shows great potential for a beneficial recovery of these antioxidants. This is the reason why a growing number of studies deal with a combined wastewater treatment, which, besides water purification, also regards the ability of recovering polyphenols. This article is an overview of reports concerning polyphenol recovery from OMW via membrane technologies. Results: Patents and studies, which appeared in literature, are reviewed in order to identify the potential of membranes as well as making comparisons possible. Some pretreatments, feasible for membrane processes, are covered. Depending on the initial wastewater and its polyphenol content the concentration in the obtained solution ranges from 0.5-19.3 g L-1 polyphenols. An example mentioned in WO2005/123603 even obtains a concentration of 30 g L-1. Polyphenols such as hydroxytyrosol, protocatechuic acid, tyrosol, caffeic acid and oleuropein were found in this concentrate and make it suitable for the use in industry. Conclusion: The membrane processes in sequential design in particular show good results and offer an alternative to other OMW treatments especially in terms of polyphenol recovery.

  8. Principles of processes used for coal gas cleaning and recovery of chemical products of coking. Part II. [Poland

    Energy Technology Data Exchange (ETDEWEB)

    Ulatowski, R.

    1983-02-01

    This paper discusses removal of tars, ammonia, benzene and desulfurization of coal gas from black coal coking. About 30% of coal gas produced by coking plants in Poland is desulfurized. The average content of hydrogen sulfide in coal gas ranges from 6 to 8 g/m/sup 3/. After desulfurization hydrogen sulfur content does not exceed 0.2 g/m/sup 3/. Two processes are used in Poland for coal gas desulfurization: the vacuum carbonate process and the Thylox process. Chemical reactions during gas desulfurization with the two processes are discussed. Regeneration systems, productivity and efficiency of gas desulfurization using the two processes are compared. The following processes used in other countries are comparatively evaluated: the Fumaks-Rodax process in Japan, the Perox process, the Stretford process, the Sulfiban process in the USA and the Claus process.

  9. Rethinking the Ancient Sulfur Cycle

    Science.gov (United States)

    Fike, David A.; Bradley, Alexander S.; Rose, Catherine V.

    2015-05-01

    The sulfur biogeochemical cycle integrates the metabolic activity of multiple microbial pathways (e.g., sulfate reduction, disproportionation, and sulfide oxidation) along with abiotic reactions and geological processes that cycle sulfur through various reservoirs. The sulfur cycle impacts the global carbon cycle and climate primarily through the remineralization of organic carbon. Over geological timescales, cycling of sulfur is closely tied to the redox state of Earth's exosphere through the burial of oxidized (sulfate) and reduced (sulfide) sulfur species in marine sediments. Biological sulfur cycling is associated with isotopic fractionations that can be used to trace the fluxes through various metabolic pathways. The resulting isotopic data provide insights into sulfur cycling in both modern and ancient environments via isotopic signatures in sedimentary sulfate and sulfide phases. Here, we review the deep-time δ34S record of marine sulfates and sulfides in light of recent advances in understanding how isotopic signatures are generated by microbial activity, how these signatures are encoded in marine sediments, and how they may be altered following deposition. The resulting picture shows a sulfur cycle intimately coupled to ambient carbon cycling, where sulfur isotopic records preserved in sedimentary rocks are critically dependent on sedimentological and geochemical conditions (e.g., iron availability) during deposition.

  10. Design and Realization of Sulfuric Acid Process Calculation Software%硫酸工艺计算软件的设计与实现

    Institute of Scientific and Technical Information of China (English)

    郭凯; 黄卫华; 曹霞

    2014-01-01

    Sulfuric acid process design calculation is featured by many parameters and huge calculated amount. Formulate sulfuric acid process design calculation software by using computer programming technique, which can provide electronic-service when huge calculation needed for sulfuric acid design. Therefore, convenient and swift computer calculation take place traditional hand computation, which gives fully play to superiority of computer technology. Emancipate people from miscellaneous and repeated calculation so as to reduce the design cost, decrease the design cycle sharply and improve the work efficiency.%硫酸工艺设计计算存在参数多、计算量大的特点。采用计算机编程技术编制硫酸工艺设计计算软件,为硫酸工艺设计时大量的计算提供电子化服务,以方便快捷的计算机计算代替了传统的手工计算,充分发挥了计算机技术的优势,把人从繁杂和重复的计算劳动中解放出来,有效地降低设计成本,大幅减少了设计周期,提高了工作效率。

  11. Improved photovoltaic and grain boundary characteristics of single elementary target-sputtered Cu2ZnSnSe4 thin films by post sulfurization/selenization process

    International Nuclear Information System (INIS)

    A potential way to improve the quality of Cu2ZnSnSe4 absorber thin film by a one step process of sputtering using a single elementary target is proposed for thin film solar cells. As critical parameters, different S/Se ratios and grain boundary characteristics are achieved by adjusting sequential sulfurization and selenization post-treatment. The simple sulfurization of as-deposited film at 530 °C in H2S is not effective in raising the performance but the additional Se annealing at a shorter duration of 5 min improves conversion efficiency from 0.12 to 3.21% with a drastic increase of the open circuit voltage. Positively-charged grain boundaries with narrow potential peaks seem to play a critical role for effective exciton separation and higher efficiency. The improvement is also understood as related to well-defined microstructures and the variable optical band gap. (paper)

  12. Spatial resolution recovery utilizing multi-ray tracing and graphic processing unit in PET image reconstruction

    International Nuclear Information System (INIS)

    Depth-of-interaction (DOI) poses a major challenge for a PET system to achieve uniform spatial resolution across the field-of-view, particularly for small animal and organ-dedicated PET systems. In this work, we implemented an analytical method to model system matrix for resolution recovery, which was then incorporated in PET image reconstruction on a graphical processing unit platform, due to its parallel processing capacity. The method utilizes the concepts of virtual DOI layers and multi-ray tracing to calculate the coincidence detection response function for a given line-of-response. The accuracy of the proposed method was validated for a small-bore PET insert to be used for simultaneous PET/MR breast imaging. In addition, the performance comparisons were studied among the following three cases: 1) no physical DOI and no resolution modeling; 2) two physical DOI layers and no resolution modeling; and 3) no physical DOI design but with a different number of virtual DOI layers. The image quality was quantitatively evaluated in terms of spatial resolution (full-width-half-maximum and position offset), contrast recovery coefficient and noise. The results indicate that the proposed method has the potential to be used as an alternative to other physical DOI designs and achieve comparable imaging performances, while reducing detector/system design cost and complexity. (paper)

  13. Shape Memory as a Process: Optimizing Polymer Design for Shape Recovery

    Science.gov (United States)

    Vaia, Richard; Koerner, Hilmar; Lee, Kyungmin; Strong, Robert; Smith, Mattew; Wang, Huabin; White, Tim; Tan, Loon-Seng

    2012-02-01

    Shape memory is a process that enables the reversible storage and recovery of mechanical energy through a change in shape. Polymers provide a unique alternative to kinematic designs and other materials (e.g. metallic alloys) for applications requiring large deformation and novel control options. The effect control of storage and relaxation of strain energy associated with chain deformation depends on the nonlinear visco-elasitc behavior and glassy dynamics of the polymer network. Considering the molecular understanding of rubbery elasticity, chain entanglements in concentrated polymer liquids, affine deformation of networks, and glass fragility, heuristic guidelines can be formulated to optimize the molecular design of a polymer for shape memory. These are applied to the development of a polymer system for shape memory processes at high-temperature (200^oC). The low-crosslink density polyimide exhibits very rapid shape recovery, excellent fixity, high creep resistance, and good cyclability. Furthermore, the molecular design affords a very narrow temperature range for programming and triggering shape change that can also be accessed by photo-isomerization of the cross-link nodes.

  14. APPLICATIONS OF THERMAL ENERGY STORAGE TO WASTE HEAT RECOVERY IN THE FOOD PROCESSING INDUSTRY, Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, W. L.; Christenson, James A.

    1979-07-31

    A project is discussed in which the possibilities for economical waste heat recovery and utilization in the food industry were examined. Waste heat availability and applications surveys were performed at two manufacturing plants engaged in low temperature (freezing) and high temperature (cooking, sterilizing, etc.) food processing. The surveys indicate usable waste heat is available in significant quantities which could be applied to existing, on-site energy demands resulting in sizable reductions in factory fuel and energy usage. At the high temperature plant, the energy demands involve the heating of fresh water for boiler make-up, for the food processes and for the daily clean-up operation. Clean-up poses an opportunity for thermal energy storage since waste heat is produced during the one or two production shifts of each working day while the major clean-up effort does not occur until food production ends. At the frozen food facility, the clean-up water application again exists and, in addition, refrigeration waste heat could also be applied to warm the soil beneath the ground floor freezer space. Systems to recover and apply waste heat in these situations were developed conceptually and thermal/economic performance predictions were obtained. The results of those studies indicate the economics of waste heat recovery can be attractive for facilities with high energy demand levels. Small factories, however, with relatively low energy demands may find the economics marginal although, percentagewise, the fuel and energy savings are appreciable.

  15. Recovery of Zn from acid mine water and electric arc furnace dust in an integrated process.

    Science.gov (United States)

    Carranza, Francisco; Romero, Rafael; Mazuelos, Alfonso; Iglesias, Nieves

    2016-01-01

    In this paper, the purification of acid mine water and the treatment of electric arc furnace dust (EAFD) are integrated into one process with the aim of recovering the Zn content of both effluent and waste. Zinc recovery can reduce the cost of their environmental management: purified acid mine water is discharged after removing all metals; EAFD ceases to be hazardous waste; and Zn is valorised. The process consists of the recovery of Zn as zinc oxide and its purification into commercial products. First, EAFD is leached with acid water and the dissolved metals are selectively precipitated as hydroxides. After EADF leaching, ferrous iron is bio-oxidized and Fe and Al are then precipitated; in the following stage, Cu, Ni, Co and Cd are cemented and finally Zn is precipitated as ZnO. In order to purify water that finally is discharged to a river, lime is used as the neutralizing agent, which results in a precipitate of mainly gypsum, MnO, and ZnO. From the impure zinc oxide produced, various alternatives for the attainment of commercial products, such as basic zinc carbonate and electrolytic zinc, are studied in this work. PMID:26433358

  16. Spatial resolution recovery utilizing multi-ray tracing and graphic processing unit in PET image reconstruction

    Science.gov (United States)

    Liang, Yicheng; Peng, Hao

    2015-02-01

    Depth-of-interaction (DOI) poses a major challenge for a PET system to achieve uniform spatial resolution across the field-of-view, particularly for small animal and organ-dedicated PET systems. In this work, we implemented an analytical method to model system matrix for resolution recovery, which was then incorporated in PET image reconstruction on a graphical processing unit platform, due to its parallel processing capacity. The method utilizes the concepts of virtual DOI layers and multi-ray tracing to calculate the coincidence detection response function for a given line-of-response. The accuracy of the proposed method was validated for a small-bore PET insert to be used for simultaneous PET/MR breast imaging. In addition, the performance comparisons were studied among the following three cases: 1) no physical DOI and no resolution modeling; 2) two physical DOI layers and no resolution modeling; and 3) no physical DOI design but with a different number of virtual DOI layers. The image quality was quantitatively evaluated in terms of spatial resolution (full-width-half-maximum and position offset), contrast recovery coefficient and noise. The results indicate that the proposed method has the potential to be used as an alternative to other physical DOI designs and achieve comparable imaging performances, while reducing detector/system design cost and complexity.

  17. Technical and economic analysis of natural ga decompression: recovery of both electricity and process frigories

    International Nuclear Information System (INIS)

    The most significant results of the economic analysis on natural gas decompression, specifically referring to EniChem's newly built plant in Porto Marghera, are shown in this article. The analysis was carried out in the framework of rational utilization of energy in compliance with Law No.9 of January 9, 1991. In order to optimize the final use of energy, the service rendered being equal (natural gas was decompressed owing to safety and technical reasons), a possible solution was found, i.e. to replace thermodynamic lamination by an expansion process in a two-stage turbine expansor (recovery of physical energy in pressure). Thanks to this new solution, the above mentioned recovery operation can be integrated by recovering the frigories associated with the availability of the fluid stream (physical energy in temperature) at the outlet of the generator, in order to supply the refrigerating quantity needed to carry out some phases of the steam-cracking process, which takes place in an area lying close to the new decompression plant

  18. Recovery of nickel from aqueous solutions by complexation-ultrafiltration process with sodium polyacrylate and polyethylenimine.

    Science.gov (United States)

    Shao, Jiahui; Qin, Shu; Davidson, Joshua; Li, Wenxi; He, Yiliang; Zhou, H Susan

    2013-01-15

    The recovery of nickel from aqueous dilute solutions by complexation-ultrafiltration process with sodium polyacrylate (PAAS) and polyethylenimine (PEI) was studied. Experiments were performed as a function of aqueous pH, polymer/Ni(2+) ratio and background electrolyte concentration. At optimum experimental conditions, the nickel removal rate reaches 99.5% using PAAS and 93.0% using PEI as the complexation agent. The nickel removal rate was found to decrease as the adding salt NaCl concentration increases for both complexation agents. A series of experiments implied that the mechanism could be the compressing electric double layer other than the competitive complexation. Diafiltration technique was further performed to regenerate complexation agents and recover nickel. The nickel removal rates were found to be close to those obtained with the original PEI and PAAS. Finally, Langmuir-type binding isotherm equation was employed to evaluate the extent of nickel bound to PAAS and PEI. The overall results from the two-step process of complexation-UF and decomplexation-UF separation showed that it could be a promising method for nickel removal and recovery from aqueous solutions. PMID:23177250

  19. Effect of dissolved oxygen on elemental sulfur generation in sulfide and nitrate removal process: characterization, pathway, and microbial community analysis.

    Science.gov (United States)

    Wang, Xiaowei; Zhang, Yu; Zhang, Tingting; Zhou, Jiti

    2016-03-01

    Microaerobic bioreactor treatment for enriched sulfide and nitrate has been demonstrated as an effective strategy to improve the efficiencies of elemental sulfur (S(0)) generation, sulfide oxidation, and nitrate reduction. However, there is little detailed information for the effect and mechanism of dissolved oxygen (DO) on the variations of microbial community in sulfur generation, sulfide oxidation, and nitrate reduction systems. Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) was employed to evaluate the variations of microbial community structures in a sulfide oxidation and nitrate reduction reactor under different DO conditions (DO 0-0.7 mg · L(-1)). Experimental results revealed that the activity of sulfide-oxidizing bacteria (SOB) and nitrate-reducing bacteria (NRB) could be greatly stimulated in 0.1-0.3 mg-DO · L(-1). However, when the DO concentration was further elevated to more than 0.5 mg · L(-1), the abundance of NRB was markedly decreased, while the heterotrophic microorganisms, especially carbon degradation species, were enriched. The reaction pathways for sulfide and nitrate removal under microaerobic conditions were also deduced by combining batch experiments with functional species analysis. It was likely that the oxidation of sulfide to sulfur could be performed by both aerobic heterotrophic SOB and sulfur-based autotrophic denitrification bacteria with oxygen and nitrate as terminal electron acceptor, respectively. The nitrate could be reduced to nitrite by both autotrophic and heterotrophic denitrification, and then the generated nitrite could be completely converted to nitrogen gas via heterotrophic denitrification. This study provides new insights into the impacts of microaerobic conditions on the microbial community functional structures of sulfide-oxidizing, nitrate-reducing, and sulfur-producing bioreactors, which revealing the potential linkage between functional microbial communities and

  20. Flow sheet model evaluation of nuclear hydrogen steelmaking processes with VHTR-IS (very high temperature reactor and iodine-sulfur process)

    International Nuclear Information System (INIS)

    Nuclear hydrogen steelmaking (NHS) and nuclear hydrogen partial reduction steelmaking (NHPRS) systems were proposed using very high temperature reactor, and thermochemical hydrogen production iodine-sulfur process. Heat input and CO2 emissions of these systems were analyzed by heat and mass balance calculation. Total net heat input to the NHS system was 28.4 GJ/t-high quality steel (HQS), including material production, material transportation, and power generation. This value was much larger than that of a blast furnace steelmaking (BFS) system of 17.6 GJ/t-HQS. Reduction of hydrogen consumption in the shaft furnace and electricity consumption in the electric arc furnace were desired for lowering the heat input. Total net heat input of a NHPRS system was 31.9 GJ/t-HQS. Optimization of operation parameters such as the reduction ratio of partial reduced ore (PRO) and ratio of the PRO input to the blast furnace is desired to decrease the heat input. CO2 emissions of the NHS system and the NHPRS system were 9% and 50% of that from the BFS system. Substitution of coal by hydrogen and reduction of transportation weight contributed to the reduction. Steelmaking cost was also evaluated. When steelmaking scale of each system was unified to one million t-HQS/y, NHS was economically competitive to BFS and Midrex steelmaking. And NHS was advantageous at higher cost of resources. (author)

  1. Application of waste heat powered absorption refrigeration system to the LNG recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Kalinowski, Paul; Hwang, Yunho; Radermacher, Reinhard [Center for Environmental Energy Engineering, Department of Mechanical Engineering, University of Maryland, College Park, MD 20742 (United States); Al Hashimi, Saleh; Rodgers, Peter [The Petroleum Institute, Abu Dhabi (United Arab Emirates)

    2009-06-15

    The recovery process of the liquefied natural gas requires low temperature cooling, which is typically provided by the vapor compression refrigeration systems. The usage of an absorption refrigeration system powered by waste heat from the electric power generating gas turbine could provide the necessary cooling at reduced overall energy consumption. In this study, a potential replacement of propane chillers with absorption refrigeration systems was theoretically analyzed. From the analysis, it was found that recovering waste heat from a 9 megawatts (MW) electricity generation process could provide 5.2 MW waste heat produced additional cooling to the LNG plant and save 1.9 MW of electricity consumption. Application of the integrated cooling, heating, and power is an excellent energy saving option for the oil and gas industry. (author)

  2. Gas-assisted gravity drainage (GAGD) process for improved oil recovery

    Science.gov (United States)

    Rao, Dandina N.

    2012-07-10

    A rapid and inexpensive process for increasing the amount of hydrocarbons (e.g., oil) produced and the rate of production from subterranean hydrocarbon-bearing reservoirs by displacing oil downwards within the oil reservoir and into an oil recovery apparatus is disclosed. The process is referred to as "gas-assisted gravity drainage" and comprises the steps of placing one or more horizontal producer wells near the bottom of a payzone (i.e., rock in which oil and gas are found in exploitable quantities) of a subterranean hydrocarbon-bearing reservoir and injecting a fluid displacer (e.g., CO.sub.2) through one or more vertical wells or horizontal wells. Pre-existing vertical wells may be used to inject the fluid displacer into the reservoir. As the fluid displacer is injected into the top portion of the reservoir, it forms a gas zone, which displaces oil and water downward towards the horizontal producer well(s).

  3. Analysis of Space Shuttle Ground Support System Fault Detection, Isolation, and Recovery Processes and Resources

    Science.gov (United States)

    Gross, Anthony R.; Gerald-Yamasaki, Michael; Trent, Robert P.

    2009-01-01

    As part of the FDIR (Fault Detection, Isolation, and Recovery) Project for the Constellation Program, a task was designed within the context of the Constellation Program FDIR project called the Legacy Benchmarking Task to document as accurately as possible the FDIR processes and resources that were used by the Space Shuttle ground support equipment (GSE) during the Shuttle flight program. These results served as a comparison with results obtained from the new FDIR capability. The task team assessed Shuttle and EELV (Evolved Expendable Launch Vehicle) historical data for GSE-related launch delays to identify expected benefits and impact. This analysis included a study of complex fault isolation situations that required a lengthy troubleshooting process. Specifically, four elements of that system were considered: LH2 (liquid hydrogen), LO2 (liquid oxygen), hydraulic test, and ground special power.

  4. DEVELOPMENT AND OPTIMIZATION OF GAS-ASSISTED GRAVITY DRAINAGE (GAGD) PROCESS FOR IMPROVED LIGHT OIL RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    Dandina N. Rao; Subhash C. Ayirala; Madhav M. Kulkarni; Amit P. Sharma

    2004-10-01

    This report describes the progress of the project ''Development and Optimization of Gas-Assisted Gravity Drainage (GAGD) Process for Improved Light Oil Recovery'' for the duration of the second project year (October 1, 2003--September 30, 2004). There are three main tasks in this research project. Task 1 is scaled physical model study of GAGD process. Task 2 is further development of vanishing interfacial tension (VIT) technique for miscibility determination. Task 3 is determination of multiphase displacement characteristics in reservoir rocks. In Section I, preliminary design of the scaled physical model using the dimensional similarity approach has been presented. Scaled experiments on the current physical model have been designed to investigate the effect of Bond and capillary numbers on GAGD oil recovery. Experimental plan to study the effect of spreading coefficient and reservoir heterogeneity has been presented. Results from the GAGD experiments to study the effect of operating mode, Bond number and capillary number on GAGD oil recovery have been reported. These experiments suggest that the type of the gas does not affect the performance of GAGD in immiscible mode. The cumulative oil recovery has been observed to vary exponentially with Bond and capillary numbers, for the experiments presented in this report. A predictive model using the bundle of capillary tube approach has been developed to predict the performance of free gravity drainage process. In Section II, a mechanistic Parachor model has been proposed for improved prediction of IFT as well as to characterize the mass transfer effects for miscibility development in reservoir crude oil-solvent systems. Sensitivity studies on model results indicate that provision of a single IFT measurement in the proposed model is sufficient for reasonable IFT predictions. An attempt has been made to correlate the exponent (n) in the mechanistic model with normalized solute compositions present in

  5. Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes

    Energy Technology Data Exchange (ETDEWEB)

    Yortsos, Y.C.

    2001-05-29

    This report is an investigation of various multi-phase and multiscale transport and reaction processes associated with heavy oil recovery. The thrust areas of the project include the following: Internal drives, vapor-liquid flows, combustion and reaction processes, fluid displacements and the effect of instabilities and heterogeneities and the flow of fluids with yield stress. These find respective applications in foamy oils, the evolution of dissolved gas, internal steam drives, the mechanics of concurrent and countercurrent vapor-liquid flows, associated with thermal methods and steam injection, such as SAGD, the in-situ combustion, the upscaling of displacements in heterogeneous media and the flow of foams, Bingham plastics and heavy oils in porous media and the development of wormholes during cold production.

  6. Process stability for chemical recovery units: Which black liquor firing control strategies enhance stability?

    Energy Technology Data Exchange (ETDEWEB)

    Clay, D.T.; Frederickson, J.O.; Andrews, J.R. [James River Corp., Berlin, NH (United States). Engineering Dept.

    1995-12-31

    Black liquor firing control strategies strive to buffer chemical recovery units (CRU) from changes in kraft pulp mill process. The importance of firing control strategy has increased recently with the trend to link concentrators directly to CRU liquor headers to ensure minimal liquor storage. Four control strategies were evaluated: (1) black liquor nozzle pressure, (2) black liquor volumetric flow, (3) black liquor solids mass flow, and (4) energy flow control. The variation between the base case and the four different control strategies was evaluated by changes in six process parameters, i.e., pressure, velocity, solids mass flow, energy released, droplet diameter, and droplet evaporative load. Results indicated that for non-fouling units, the energy release strategy provided the best stability. For fouling units, the choice was less obvious; none of the evaluated control strategies ranked consistently best. Liquor header (nozzle) pressure control proved to be least desirable. 10 refs., 8 figs., 4 tabs.

  7. Performance Evaluation of Absorbent Solution for Draw Solute Recovery in Forward Osmosis Desalination Process

    International Nuclear Information System (INIS)

    Although forward osmosis desalination technology has drawn substantial attention as a next-generation desalination method, the energy efficiency of its draw solution treatment process should be improved for its commercialization. When ammonium bicarbonate is used as the draw solute, the system consists of forward-osmosis membrane modules, draw solution separation and recovery processes. Mixed gases of ammonia and carbon dioxide generated during the draws solution separation, need to be recovered to re-concentrate ammonium bicarbonate solution, for continuous operation as well as for the economic feasibility. The diluted ammonium bicarbonate solution has been proposed as the absorbent for the draw solution regeneration. In this study, experiments are conducted to investigate performance and features of the absorption corresponding to absorbent concentration. It is concluded that ammonium bicarbonate solution can be used to recover the generated ammonia and carbon dioxide. The results will be applied to design and operation of pilot-scale forward-osmosis desalination system

  8. Application of the flotation process in the silver recovery from the wastes generated during the silvery semi-products manufacturing

    OpenAIRE

    B. Oleksiak; A. Blacha-Grzechnik; G. Siwiec

    2012-01-01

    In this work, the results of the flotation process application in the silver recovery from the wastes generated during the silvery semi-products manufacturing, are shown. The flotation process parameters, i.e. time of process, rotation frequency, gas flow rate and flotation reagents, were optimized.

  9. Accident and Off-Normal Response and Recovery from Multi-Canister Overpack (MCO) Processing Events

    International Nuclear Information System (INIS)

    In the process of removing spent nuclear fuel (SNF) from the K Basins through its subsequent packaging, drymg, transportation and storage steps, the SNF Project must be able to respond to all anticipated or foreseeable off-normal and accident events that may occur. Response procedures and recovery plans need to be in place, personnel training established and implemented to ensure the project will be capable of appropriate actions. To establish suitable project planning, these events must first be identified and analyzed for their expected impact to the project. This document assesses all off-normal and accident events for their potential cross-facility or Multi-Canister Overpack (MCO) process reversal impact. Table 1 provides the methodology for establishing the event planning level and these events are provided in Table 2 along with the general response and recovery planning. Accidents and off-normal events of the SNF Project have been evaluated and are identified in the appropriate facility Safety Analysis Report (SAR) or in the transportation Safety Analysis Report for Packaging (SARP). Hazards and accidents are summarized from these safety analyses and listed in separate tables for each facility and the transportation system in Appendix A, along with identified off-normal events. The tables identify the general response time required to ensure a stable state after the event, governing response documents, and the events with potential cross-facility or SNF process reversal impacts. The event closure is predicated on stable state response time, impact to operations and the mitigated annual occurrence frequency of the event as developed in the hazard analysis process

  10. Oxidative stripping process for the recovery of uranium from wet-process phosphoric acid

    International Nuclear Information System (INIS)

    The present invention is a two-cycle liquid-liquid extraction process in which the uranium, as uranous ion, is extracted with a first-cycle extractant and then oxidatively stripped with a concentrated phosphoric acid solution. This uranium-enriched strip solution then serves as feed for a second liquid-liquid solvent extraction cycle where uranyl ions are extracted into an organic phase, stripped from the organic phase with ammonium carbonate soluton, and recovered as a high-grade u3O8 product. (author)

  11. STIMULI-RESPONSIVE POLYMERS WITH ENHANCED EFFICIENCY IN RESERVOIR RECOVERY PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    Charles McCormick; Roger Hester

    2004-09-30

    This sixth and final progress report for DOE Award Number DE-FC26-01BC15317 describes research during the period March 01, 2004 through August 31, 2004 performed at the University of Southern Mississippi on ''Stimuli Responsive Polymers with Enhanced Efficiency in Reservoir Recovery'' processes. Significantly, terpolymers that are responsive to changes in pH and ionic strength have been synthesized, characterized, and their solution properties have been extensively examined. Terpolymers composed of acrylamide, a carboxylated acrylamido monomer (AMBA), and a quaternary ammonium monomer (AMBATAC) with balanced compositions of the latter two, exhibit increases in aqueous solution viscosity as NaCl concentration is increased. This increase in polymer coil size can be expected upon injection of this type of polymer into oil reservoirs of moderate-to-high salinity, leading to better mobility control. The opposite effect (loss of viscosity) is observed for conventional polymer systems. Additionally polymer mobility characteristics have been conducted for a number of hydrophilic copolymers utilizing an extensional flow apparatus and size exclusion chromatography. This study reveled that oil recovery enhancement through use of polymers in a water flood is due to the polymer's resistance to deformation as it flows through the reservoir. Individual polymers when in aqueous solution form coils. The larger the polymer's coil size, the greater the polymer's resistance to extensional flow and the more effective the polymer is in enhancing oil recovery. Large coil sizes are obtained by increasing the polymer molecular weight and having macromolecular structures that favor greater swelling of the coil by the aqueous solvent conditions (temperature, pH and electrolyte concentration) existing in the reservoir.

  12. A conceptional design, cost and sensitivity analysis on adsorption process for uranium recovery from seawater

    International Nuclear Information System (INIS)

    The system model for a conceptional design and cost estimation was studied on a multi-layered fluidizing bed with a pump which used hydrous titanium oxide (HTO) and amidoxime resin (AOR) as adsorbents. The cost effect of some parameters, namely characteristics of adsorbent, operating conditions, price of materials and some others, were estimated, and finally there was shown a direction of improvement and a possibility of cost reduction. The conceptional design and operating condition were obtained from the balance point on expansion ratio, recovery and characteristics of adsorbent. A suitable plan was obtained from the minimum cost condition in some level of the expansion ratio and some parameters. HTO was heavy in density and cheap in price. The main results of the study indicated that the thickness of the bed was 1 m, the linear velocity of seawater was 52 m/hr, the number of bed layers was 4, the construction cost of a 100 t/y plant was 10 billion yen, and the uranium cost was 160 $/1b. AOR had a large adsorption capacity. As the main results, the thickness of bed was 0.08 m, the linear velosity of seawater was 11.6 m, the number of the bed layers was 27, the construction cost of a 100 t/y plant was 15 billion yen, and the uranium cost was 280 $/1b. The size of the 100 t/y plant was about 800 m length x 80 m depth x 30 m height at 80 % of recovery. An increase of adsorption capacity in HTO, and an increase of density and particle size in AOR had the greatest merit for cost reduction. Other effective parameters were the adsorption velocity, the recovery, temperature, the price of adsorbent, the manufacturing cost of instrument, and the rate of interest. The cost of uranium by this process had a possibility of cost reduction to 67 $/1b at HTO and 79 $/1b at AOR. (author)

  13. Thermodynamic characterization of metal dissolution and inhibitor adsorption processes in the low carbon steel/mimosa tannin/sulfuric acid system

    Science.gov (United States)

    Martinez, Sanja; Stern, Ivica

    2002-10-01

    The corrosion rates in the presence of mimosa tannin as a low carbon steel corrosion inhibitor in sulfuric acid media, were measured by the weight loss method, in the range of temperatures from 20 to 60 °C. The Temkin, Frumkin and Freundlich isotherms were tested for their fit to the experimental data. The free energies and enthalpies for the adsorption process and the apparent activation energies, enthalpies and entropies of the dissolution process were determined. The fundamental thermodynamic functions were used to glean important information about the mimosa tannin inhibitory behavior. The results were explained in terms of chemical thermodynamics.

  14. The relationship between coping styles and psychological adaptation in the recovery process: patients with coronary heart disease

    Directory of Open Access Journals (Sweden)

    Besharat M.A.

    2008-11-01

    Full Text Available "nBackground: The relationship between coping styles and psychological adaptation during the recovery process was investigated in a sample of coronary heart disease (CHD patients. "nMethods: One hundred and fifty patients from Shahid Rajaee Heart Center, Tehran, Iran, were included in this study at intake and forty five patients (27 men, 18 women participated in the follow-up study. All participants were asked to complete the Tehran Coping Styles Scale (TCSS and Mental Health Inventory (MHI. The Recovery Process Questionnaire (RPQ was completed using each patient's medical file and clinical examinations by cardiologists. Styles of coping with stress were categorized as problem-focused, positive emotional-focused and negative emotional-focused. Psychological adaptation included psychological well-being and psychological distress. "nResults: Objective recovery status showed no significant correlation with either coping styles or psychological adaptation. Perceived recovery revealed a significant positive association with negative emotional-focused coping (p<0.05, but no significant correlation with other coping and psychological adaptation variables. Perceived recovery revealed a significant negative association with psychological distress (p<0.05, but showed no significant correlation with psychological well-being. "nConclusions: Perceived recovery in CHD patients is positively influenced by negative emotional-focused coping styles. Results and implications are discussed specifically in terms of the possible reasons for the positive relationship between perceived recovery and negative emotional-focused coping.

  15. Gasoline from coal in the state of Illinois: feasibility study. Volume I. Design. [KBW gasification process, ICI low-pressure methanol process and Mobil M-gasoline process

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    Volume 1 describes the proposed plant: KBW gasification process, ICI low-pressure methanol process and Mobil M-gasoline process, and also with ancillary processes, such as oxygen plant, shift process, RECTISOL purification process, sulfur recovery equipment and pollution control equipment. Numerous engineering diagrams are included. (LTN)

  16. Waste Heat Recovery and Recycling in Thermal Separation Processes: Distillation, Multi-Effect Evaporation (MEE) and Crystallization Processes

    Energy Technology Data Exchange (ETDEWEB)

    Emmanuel A. Dada; Chandrakant B. Panchal; Luke K. Achenie; Aaron Reichl; Chris C. Thomas

    2012-12-03

    Evaporation and crystallization are key thermal separation processes for concentrating and purifying inorganic and organic products with energy consumption over 1,000 trillion Btu/yr. This project focused on a challenging task of recovering low-temperature latent heat that can have a paradigm shift in the way thermal process units will be designed and operated to achieve high-energy efficiency and significantly reduce the carbon footprint as well as water footprint. Moreover, this project has evaluated the technical merits of waste-heat powered thermal heat pumps for recovery of latent heat from distillation, multi-effect evaporation (MEE), and crystallization processes and recycling into the process. The Project Team has estimated the potential energy, economics and environmental benefits with the focus on reduction in CO2 emissions that can be realized by 2020, assuming successful development and commercialization of the technology being developed. Specifically, with aggressive industry-wide applications of heat recovery and recycling with absorption heat pumps, energy savings of about 26.7 trillion Btu/yr have been estimated for distillation process. The direct environmental benefits of this project are the reduced emissions of combustible products. The estimated major reduction in environmental pollutants in the distillation processes is in CO2 emission equivalent to 3.5 billion lbs/year. Energy consumption associated with water supply and treatments can vary between 1,900 kWh and 23,700 kWh per million-gallon water depending on sources of natural waters [US DOE, 2006]. Successful implementation of this technology would significantly reduce the demand for cooling-tower waters, and thereby the use and discharge of water treatment chemicals. The Project Team has also identified and characterized working fluid pairs for the moderate-temperature heat pump. For an MEE process, the two promising fluids are LiNO3+KNO3+NANO3 (53:28:19 ) and LiNO3+KNO3+NANO2

  17. Uncertainty in Population Estimates for Endangered Animals and Improving the Recovery Process

    OpenAIRE

    Rachlow, Janet L; Goble, Dale D.; Matthew Zak; J. Michael. Scott; Katie Hammond; Haines, Aaron M.

    2013-01-01

    Simple Summary The objective of our study was to evaluate the mention of uncertainty (i.e., variance) associated with population size estimates within U.S. recovery plans for endangered animals. To do this we reviewed all finalized recovery plans for listed terrestrial vertebrate species. We found that more recent recovery plans reported more estimates of population size and uncertainty. Also, bird and mammal recovery plans reported more estimates of population size and uncertainty. We recomm...

  18. Applications of thermal energy storage to waste heat recovery in the food processing industry

    Science.gov (United States)

    Wojnar, F.; Lunberg, W. L.

    1980-01-01

    A study to assess the potential for waste heat recovery in the food industry and to evaluate prospective waste heat recovery system concepts employing thermal energy storage was conducted. The study found that the recovery of waste heat in canning facilities can be performed in significant quantities using systems involving thermal energy storage that are both practical and economical. A demonstration project is proposed to determine actual waste heat recovery costs and benefits and to encourage system implementation by the food industry.

  19. Tensiomygraphic Measurement of Atrophy Related Processes During Bed Rest and Recovery

    Science.gov (United States)

    Simunic, B. ostjan; Degens, Hans; Rittweger, Jorn; Narici, Marcco; Pisot, Venceslav; Mekjavic, Igor B.; Pisot, Rado

    2013-02-01

    Tensiomyographic (TMG) parameters were recently proposed for a non-invasive estimation of MHC distribution in human vastus lateralis muscle. However, TMG potential is even higher, offers additional insight into the skeletal muscle physiology, especially in the field of atrophy and hypertrophy. The purpose of this study is in developing time dynamics of TMG-measured contraction time (Tc) and maximal response amplitude (Dm), together with muscle belly thickness, measure thoroughly during 35-day bed rest and followed in 30-day recovery (N = 10 males; age 24.3 ± 2.6 years). Measurements were performed in two postural muscles (vastus medialis and lateralis) and one non-postural muscle (biceps femoris). During bed rest period we found different dynamics of muscle thickness decrease and Dm increase. Tc was unchanged in postural muscles, but in non-postural muscle increased significantly and stayed as such even at the end of recovery. We could conclude that TMG related parameters are more sensitive in measuring muscle atrophic and hypertrophic processes than biomedical imaging technique. However, a mechanism that regulates Dm still needs to be identified.

  20. Dynamic Modeling of Process Technologies for Closed-Loop Water Recovery Systems

    Science.gov (United States)

    Allada, Rama Kumar; Lange, Kevin E.; Anderson, Molly S.

    2012-01-01

    Detailed chemical process simulations are a useful tool in designing and optimizing complex systems and architectures for human life support. Dynamic and steady-state models of these systems help contrast the interactions of various operating parameters and hardware designs, which become extremely useful in trade-study analyses. NASA s Exploration Life Support technology development project recently made use of such models to compliment a series of tests on different waste water distillation systems. This paper presents dynamic simulations of chemical process for primary processor technologies including: the Cascade Distillation System (CDS), the Vapor Compression Distillation (VCD) system, the Wiped-Film Rotating Disk (WFRD), and post-distillation water polishing processes such as the Volatiles Removal Assembly (VRA). These dynamic models were developed using the Aspen Custom Modeler (Registered TradeMark) and Aspen Plus(Registered TradeMark) process simulation tools. The results expand upon previous work for water recovery technology models and emphasize dynamic process modeling and results. The paper discusses system design, modeling details, and model results for each technology and presents some comparisons between the model results and available test data. Following these initial comparisons, some general conclusions and forward work are discussed.

  1. Intensified recovery of valuable products from whey by use of ultrasound in processing steps - A review.

    Science.gov (United States)

    Gajendragadkar, Chinmay N; Gogate, Parag R

    2016-09-01

    The current review focuses on the analysis of different aspects related to intensified recovery of possible valuable products from cheese whey using ultrasound. Ultrasound can be used for process intensification in processing steps such as pre-treatment, ultrafiltration, spray drying and crystallization. The combination of low-frequency, high intensity ultrasound with the pre-heat treatment minimizes the thickening or gelling of protein containing whey solutions. These characteristics of whey after the ultrasound assisted pretreatment helps in improving the efficacy of ultrafiltration used for separation and also helps in preventing the blockage of orifice of spray dryer atomizing device. Further, the heat stability of whey proteins is increased. In the subsequent processing step, use of ultrasound assisted atomization helps to reduce the treatment times as well as yield better quality whey protein concentrate (WPC) powder. After the removal of proteins from the whey, lactose is a major constituent remaining in the solution which can be efficiently recovered by sonocrystallization based on the use of anti-solvent as ethanol. The scale-up parameters to be considered during designing the process for large scale applications are also discussed along with analysis of various reactor designs. Overall, it appears that use of ultrasound can give significant process intensification benefits that can be harnessed even at commercial scale applications. PMID:27150751

  2. Effect of Sulfurization Temperature on Solution-Processed Cu2ZnSnS4 Thin Films.

    Science.gov (United States)

    Park, Si-Nae; Sung, Shi-Joon; Son, Dae-Ho; Kim, Dae-Hwan; Sim, Jun-Hyoung; Kang, Jin-Kyu

    2015-03-01

    Cu2ZnSnS4 (CZTS) solar cells are attracting significant attention as an alternative to CIGS (Culn1-xGa(x)S2) solar cells because of the non-toxic and inexpensive constituent elements of CZTS. Recently, solution-based deposition methods are being developed because they have advantages such as suitability for use in large-area deposition, high-throughput manufacturing, and a very short energy payback time with drastically lower manufacturing costs. In this work, we fabricated solution-based CZTS thin films and investigated them in order to observe the effects of sulfurization temperature on CZTS thin films. We confirmed the grain size, morphology, chemical composition, crystallinity, and electrical properties of CZTS thin films depending on various sulfurization temperatures. PMID:26413693

  3. Uncertainty in Population Estimates for Endangered Animals and Improving the Recovery Process

    Directory of Open Access Journals (Sweden)

    Janet L. Rachlow

    2013-08-01

    Full Text Available United States recovery plans contain biological information for a species listed under the Endangered Species Act and specify recovery criteria to provide basis for species recovery. The objective of our study was to evaluate whether recovery plans provide uncertainty (e.g., variance with estimates of population size. We reviewed all finalized recovery plans for listed terrestrial vertebrate species to record the following data: (1 if a current population size was given, (2 if a measure of uncertainty or variance was associated with current estimates of population size and (3 if population size was stipulated for recovery. We found that 59% of completed recovery plans specified a current population size, 14.5% specified a variance for the current population size estimate and 43% specified population size as a recovery criterion. More recent recovery plans reported more estimates of current population size, uncertainty and population size as a recovery criterion. Also, bird and mammal recovery plans reported more estimates of population size and uncertainty compared to reptiles and amphibians. We suggest the use of calculating minimum detectable differences to improve confidence when delisting endangered animals and we identified incentives for individuals to get involved in recovery planning to improve access to quantitative data.

  4. Modified sodium diuranate process for the recovery of uranium from uranium hexafluoride transport cylinder wash solution

    Science.gov (United States)

    Meredith, Austin Dean

    Uranium hexafluoride (UF6) containment cylinders must be emptied and washed every five years in order to undergo recertification, according to ANSI standards. During the emptying of the UF6 from the cylinders, a thin residue, or heel, of UF6 is left behind. This heel must be removed in order for recertification to take place. To remove it, the inside of the containment cylinder is washed with acid and the resulting solution generally contains three or four kilograms of uranium. Thus, before the liquid solution can be disposed of, the uranium must be separated. A modified sodium diuranate (SDU) uranium recovery process was studied to support development of a commercial process. This process was sought to ensure complete uranium recovery, at high purity, in order that it might be reused in the nuclear fuel cycle. An experimental procedure was designed and carried out in order to verify the effectiveness of the commercial process in a laboratory setting. The experiments involved a small quantity of dried UO2F2 powder that was dosed with 3wt% FeF3 and was dissolved in water to simulate the cylinder wash solution. Each experiment series started with a measured amount of this powder mixture which was dissolved in enough water to make a solution containing about 120 gmU/liter. The experiments involved validating the modified SDU extraction process. A potassium diuranate (KDU) process was also attempted. Very little information exists regarding such a process, so the task was undertaken to evaluate its efficacy and determine whether a potassium process yields any significant differences or advantages as compared to a sodium process. However, the KDU process ultimately proved ineffective and was abandoned. Each of the experiments was organized into a series of procedures that started with the UO2F2 powder being dissolved in water, and proceeded through the steps needed to first convert the uranium to a diuranate precipitate, then to a carbonate complex solution, and finally

  5. Selective recovery of americium alone from PUREX or COEXTM raffinate by the EXAm process

    International Nuclear Information System (INIS)

    Americium is the main contributor to the long-term radiotoxicity and to the heat generation of glasses used for the HLW conditioning. To decrease both impact on the ultimate waste and to avoid the difficult recycling of curium, the CEA has developed the EXAm process for the the separation and the recovery of the sole americium directly from PUREX or COEXTM raffinates. The principle of the EXAm process is to extract americium and light lanthanides from high nitric acid media, leaving curium and heavy lanthanides in the raffinate. A water-soluble amide molecule, TEDGA, is added in aqueous phase to increase Am/Cm and Am/heavy lanthanides selectivity, because of the preferential complexation of curium and heavy lanthanides by this diglycolamide. Many experimental data have been acquired mainly at the extraction-scrubbing step (Am/Cm separation) and were used for the development of a phenomenological model implemented in the PAREX process simulation code. The scientific feasibility demonstration of the EXAm process was then performed on a genuine PUREX raffinate in Atalante CBP hot cell in 2010. (author)

  6. Recovery process of cathode material of the spent lithium-ion batteries using Pechini methods

    International Nuclear Information System (INIS)

    This work proposes a new process of recovering LiCoO2 from spent Li-ion batteries (LIBs) by a combination of acid leaching and Pechini synthesis, as an alternative process to improve the recovery efficiency of LiCoO2 and reduce energy consumption and pollution. The effects of calcination temperature and lithium acetate addition in the synthesis on the structure and morphology of LiCoO2 powders were characterized by X-ray diffraction, Raman spectroscopy and scanning electron microscopy. According to the analysis, the crystallinity of LiCoO2 powders depends on the calcination temperature. The results indicate the layered HT-LiCoO2 powders can be obtained at 750 deg C for 24 h in oxygen with lithium salt addition. Cyclic voltammograms showed one reversible redox process at 4.0/3.85 V for the LiCoO2 obtained with lithium addition in the synthesis and irreversible redox process for the LiCoO2 obtained without lithium addition. (author)

  7. Development of an improved membrane for a vapor diffusion water recovery process. [onboard manned spacecraft

    Science.gov (United States)

    Rich, T. R.; Mix, T. W.

    1974-01-01

    Recovery of potable water from urine on manned space missions of extended duration was the objective of work aimed at the improvement of membrane performance for the vapor diffusion process (VDR). Kynar, Teflon, PVC, and polysulfone candidate membranes were evaluated from chemical, thermal, mechanical, and fabricating standpoints to determine their suitability for operation in the VDR pervaporation module. Pervaporation rates and other performance characteristics were determined in a breadboard pervaporator test rig. Kynar and Teflon membranes were demonstrated to be chemically stable at pervaporation temperatures in urine pretreated with chromic acid bactericide. The separation of the pervaporator and condenser modules, the use of a recirculating sweep gas to conduct pervaporate to the condenser, and the selection of a hollow fiber membrane configuration for pervaporator module design is recommended as a result of the investigation.

  8. Treatment of uranium bearing waste arising from solvent recovery unit of uranium processing plant

    International Nuclear Information System (INIS)

    During the regeneration of tributyl phosphate in uranium plant, a sizable volume of liquid waste containing about 70 mg/l of uranium, along with high concentrations of nitrates and carbonates, is generated. Laboratory studies revealed that the waste was not amenable to conventional treatment methods, including co-precipitation, owing to high concentration of carbonates, with which uranium forms a stable carbonato complex. Various commmercially available strongly basic anion exchangers were evaluated for the uptake of uranium from the waste under static conditions. Column studies, employing the anion-exchange resin which has shown the highest uptake, were carried out. These studies reveal the application potential of ion-exchange process not only in the treatment of uranium bearing wastes but also in the recovery of uranium. (author). 8 refs., 4 figs., 5 tabs

  9. A microencapsulation process of liquid mercury by sulfur polymer stabilization/solidification technology. Part I: Characterization of materials

    Directory of Open Access Journals (Sweden)

    López-Delgado, A.

    2012-02-01

    Full Text Available European Directives consider mercury a priority hazardous substance due to its adverse effects on human health and the environment. In response to environmental concerns, a microencapsulation process has been developed within the European LIFE program as a long-term storage option for mercury. This process leads to the obtainment of a stable concrete-like sulfur matrix that allows the immobilization of mercury. The final product, in the form of a solid block containing up to 30 % Hg, exhibits excellent mechanical properties (compressive strength 53-61MPa and flexural strength 7-10 MPa, low porosity (0.57 % PHe, very low total pore volume (0.63x10-2 cm3 g-1, and extremely low permeability (coefficient of water absorption by capillarity 0.07 g cm-2. Toxicity characteristic leaching tests reveal a mercury concentration in leachates well below the 0.2 mg L-1 set out in US EPA Land Disposal Restrictions (LDRs. The values of mercury vapor emissions of final products were lower than those of cinnabar and metacinnabar.

    Resumen Las Directivas Europeas consideran al mercurio una sustancia de peligrosidad prioritaria debido a sus efectos adversos sobre la salud humana y sobre el medio ambiente. En respuesta a estas preocupaciones ambientales, y dentro del Programa Europeo LIFE, se ha desarrollado un proceso de microencapsulación como una opción al almacenamiento a largo plazo del mercurio. Con este proceso se obtiene un material estable, tipo concreto, de matriz de azufre que permite la inmovilización del mercurio. El producto final, en forma de un bloque sólido, contiene hasta un 30 % de Hg, presenta excelentes propiedades mecánicas (resistencia a la compresión 53-61 MPa, y a la flexión 7-10 MPa, baja porosidad (0,57 % PHe, muy bajo volumen total de poro (0,63 x 10-2 cm3 g-1 y una permeabilidad extremadamente baja (coeficiente de absorción de

  10. Environmentally Friendly Recovery of Phenylacetic Acid from 7-ADCA Production Process%从7-ADCA生产过程中环境友好的回收苯乙酸

    Institute of Scientific and Technical Information of China (English)

    李珣珣; 周新基; 咸娟; 冒小青

    2015-01-01

    采用新工艺回收7-氨基-3-脱乙酰氧基头孢烷酸(7-ADCA)生产中产生的苯乙酸,并对苯乙酸回收过程中产生的废硫酸进行处理.采用硫酸(98%)洗涤二氯甲烷,硫酸与二氯甲烷适宜的体积比为1:50,洗涤好的二氯甲烷中含苯乙酸4%.蒸馏出二氯甲烷,趁热向熔融苯乙酸中加入母液,降温析出苯乙酸.晾干的苯乙酸为白色鳞片状,含量大于99%,苯乙酸母液补充部分清水套用到下一批析出苯乙酸.废浓硫酸用芬顿试剂氧化,控制80℃氧化4h,双氧水和七水硫酸亚铁重量比为6:1,废浓硫酸COD下降85%以上.氧化结束后向废硫酸中加入铁粉和双氧水,制得聚合硫酸铁.%A new technology to recover the by-product of 7-ADCA and purify the waste sulfuric acid produced in phenylacetic acid recovery process was adopted. Firstly, wash CH2Cl2 with sulfuric acid (98%) under the condition that the volumeratio of sulfuric acid to CH2Cl2 was 1:50, and the mass fraction of phenylacetic acid in washed CH2Cl2 was 4%. Secondly, distilled the CH2Cl2 and added mother liquid into the rest part--mainly fused phenylacetic acid. Thirdly, separated phenylacetic acid by the method of decrease the composition liquid temperature, the content of which was more than 99% .Then, applied the remaining with water added into the next batch. Fenton reagent was used to oxidize the waste sulfuric acid. The oxidization lasted for 4h with the controlling temperature of 80℃ and the weight ratio of H2O2 and FeSO4·7H2O was 6:1, then the COD of waste sulfuric acid decreased by more than 85%. After that, Fe and H2O2 were added into the waste sulfuric acid to produce polymeric ferric sulfate.

  11. Characteristics and adaptability of iron- and sulfur-oxidizing microorganisms used for the recovery of metals from minerals and their concentrates

    OpenAIRE

    Rawlings Douglas E

    2005-01-01

    Abstract Microorganisms are used in large-scale heap or tank aeration processes for the commercial extraction of a variety of metals from their ores or concentrates. These include copper, cobalt, gold and, in the past, uranium. The metal solubilization processes are considered to be largely chemical with the microorganisms providing the chemicals and the space (exopolysaccharide layer) where the mineral dissolution reactions occur. Temperatures at which these processes are carried out can var...

  12. DEVELOPMENT AND OPTIMIZATION OF GAS-ASSISTED GRAVITY DRAINAGE (GAGD) PROCESS FOR IMPROVED LIGHT OIL RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    Dandina N. Rao

    2003-10-01

    This is the first Annual Technical Progress Report being submitted to the U. S. Department of Energy on the work performed under the Cooperative Agreement DE-FC26-02NT15323. This report follows two other progress reports submitted to U.S. DOE during the first year of the project: The first in April 2003 for the project period from October 1, 2002 to March 31, 2003, and the second in July 2003 for the period April 1, 2003 to June 30, 2003. Although the present Annual Report covers the first year of the project from October 1, 2002 to September 30, 2003, its contents reflect mainly the work performed in the last quarter (July-September, 2003) since the work performed during the first three quarters has been reported in detail in the two earlier reports. The main objective of the project is to develop a new gas-injection enhanced oil recovery process to recover the oil trapped in reservoirs subsequent to primary and/or secondary recovery operations. The project is divided into three main tasks. Task 1 involves the design and development of a scaled physical model. Task 2 consists of further development of the vanishing interfacial tension (VIT) technique for miscibility determination. Task 3 involves the determination of multiphase displacement characteristics in reservoir rocks. Each technical progress report, including this one, reports on the progress made in each of these tasks during the reporting period. Section I covers the scaled physical model study. A survey of literature in related areas has been conducted. Test apparatus has been under construction throughout the reporting period. A bead-pack visual model, liquid injection system, and an image analysis system have been completed and used for preliminary experiments. Experimental runs with decane and paraffin oil have been conducted in the bead pack model. The results indicate the need for modifications in the apparatus, which are currently underway. A bundle of capillary tube model has been considered and

  13. Dynamic Engagement of Cognitive Control Modulates Recovery From Misinterpretation During Real-Time Language Processing.

    Science.gov (United States)

    Hsu, Nina S; Novick, Jared M

    2016-04-01

    Speech unfolds swiftly, yet listeners keep pace by rapidly assigning meaning to what they hear. Sometimes, though, initial interpretations turn out to be wrong. How do listeners revise misinterpretations of language input moment by moment to avoid comprehension errors? Cognitive control may play a role by detecting when processing has gone awry and then initiating behavioral adjustments accordingly. However, no research to date has investigated a cause-and-effect interplay between cognitive-control engagement and the overriding of erroneous interpretations in real time. Using a novel cross-task paradigm, we showed that Stroop-conflict detection, which mobilizes cognitive-control procedures, subsequently facilitates listeners' incremental processing of temporarily ambiguous spoken instructions that induce brief misinterpretation. When instructions followed incongruent Stroop items, compared with congruent Stroop items, listeners' eye movements to objects in a scene reflected more transient consideration of the false interpretation and earlier recovery of the correct one. Comprehension errors also decreased. Cognitive-control engagement therefore accelerates sentence-reinterpretation processes, even as linguistic input is still unfolding. PMID:26957521

  14. Microbial processes in the Athabasca Oil Sands and their potential applications in microbial enhanced oil recovery.

    Science.gov (United States)

    Harner, N K; Richardson, T L; Thompson, K A; Best, R J; Best, A S; Trevors, J T

    2011-11-01

    The Athabasca Oil Sands are located within the Western Canadian Sedimentary Basin, which covers over 140,200 km(2) of land in Alberta, Canada. The oil sands provide a unique environment for bacteria as a result of the stressors of low water availability and high hydrocarbon concentrations. Understanding the mechanisms bacteria use to tolerate these stresses may aid in our understanding of how hydrocarbon degradation has occurred over geological time, and how these processes and related tolerance mechanisms may be used in biotechnology applications such as microbial enhanced oil recovery (MEOR). The majority of research has focused on microbiology processes in oil reservoirs and oilfields; as such there is a paucity of information specific to oil sands. By studying microbial processes in oil sands there is the potential to use microbes in MEOR applications. This article reviews the microbiology of the Athabasca Oil Sands and the mechanisms bacteria use to tolerate low water and high hydrocarbon availability in oil reservoirs and oilfields, and potential applications in MEOR. PMID:21853326

  15. Designing of an intensification process for biosynthesis and recovery of menaquinone-7.

    Science.gov (United States)

    Berenjian, Aydin; Mahanama, Raja; Talbot, Andrea; Regtop, Hubert; Kavanagh, John; Dehghani, Fariba

    2014-02-01

    A nutritional food rich in menaquinone-7 has a potential in preventing osteoporosis and cardiovascular diseases. The static fermentation of Bacillus subtilis natto is widely regarded as an optimum process for menaquinone-7 production. The major issues for the bulk production of menaquinone-7 are the low fermentation yield, biofilm formation and the use of organic solvents for the vitamin extraction. In this study, we demonstrate that the dynamic fermentation involving high stirring and aeration rates enhances the yield of fermentation process significantly compared to static system. The menaquinone-7 concentration of 226 mg/L was produced at 1,000 rpm, 5 vvm, 40 °C after 5 days of fermentation. This concentration is 70-fold higher than commercially available food products such as natto. Additionally, it was found that more than 80% of menaquinone-7 was recovered in situ in the vegetable oil that was gradually added to the system as an anti-foaming agent. The intensification process developed in this study has a capacity to produce an oil rich in menaquinone-7 in one step and eliminate the use of organic solvents for recovery of this compound. This oil can, therefore, be used for the preparation of broad range of supplementary and dietary food products rich in menaquinone-7 to reduce the risk of osteoporotic fractures and cardiovascular diseases. PMID:24173914

  16. Integrating landfill bioreactors, partial nitritation and anammox process for methane recovery and nitrogen removal from leachate

    Science.gov (United States)

    Sun, Faqian; Su, Xiaomei; Kang, Tingting; Wu, Songwei; Yuan, Mengdong; Zhu, Jing; Zhang, Xiayun; Xu, Fang; Wu, Weixiang

    2016-06-01

    A new process consisting of a landfill bioreactor, partial-nitritation (PN) and the anammox process has been developed for landfill leachate treatment. In this study, the landfill bioreactor exhibited excellent performance in methane-rich biogas recovery, with a specific biogas yield of 0.47 L gas g‑1 COD and methane percentages of 53–76%. PN was achieved in the aerobic reactor by high free ammonia (101 ± 83 mg NH3 L‑1) inhibition for nitrite-oxidizing bacteria, and the desired PN effluent composition (effluent nitrite: ammonium ratio of 1.1 ± 0.3) was controlled by adjusting the alkalinity concentration per unit of ammonium oxidized to approximately 14.3 mg CaCO3 mg‑1 N in the influent. The startup of anammox process was successfully achieved with a membrane bioreactor in 160 d, and a maximum nitrogen removal rate of 216 mg N L‑1 d‑1 was attained for real landfill leachate treatment. The quantitative polymerase chain reaction results confirmed that the cell-specific anammox activity was approximately 68–95 fmol N cell‑1 d‑1, which finally led to the stable operation of the system.

  17. A novel approach for phosphorus recovery and no wasted sludge in enhanced biological phosphorus removal process with external COD addition.

    Science.gov (United States)

    Xia, Cheng-Wang; Ma, Yun-Jie; Zhang, Fang; Lu, Yong-Ze; Zeng, Raymond J

    2014-01-01

    In enhanced biological phosphorus removal (EBPR) process, phosphorus (P) in wastewater is removed via wasted sludge without actual recovery. A novel approach to realize phosphorus recovery with special external chemical oxygen demand (COD) addition in EBPR process was proposed. During the new operating approach period, it was found that (1) no phosphorus was detected in the effluent; (2) with an external addition of 10 % of influent COD amount, 79 % phosphorus in the wastewater influent was recovered; (3) without wasted sludge, the MLVSS concentration in the system increased from 2,010 to 3,400 mg/L and kept stable after day 11 during 24-day operating period. This demonstrates that the novel approach is feasible to realize phosphorus recovery with no wasted sludge discharge in EBPR process. Furthermore, this approach decouples P removal and sludge age, which may enhance the application of membrane bioreactor for P removal. PMID:24122666

  18. Advanced sulfur control concepts for hot-gas desulfurization technology

    International Nuclear Information System (INIS)

    twenty-five-cycle test. The sorbent was exposed for 58 consecutive days to temperatures between 600C and 800C and gas atmospheres from highly reducing to highly oxidizing without measurable loss of sulfur capacity or reactivity. In the process analysis phase of this study, a two-stage desulfurization process using cerium sorbent with SO2 regeneration followed by zinc sorbent with dilute O2 regeneration was compared to a single-stage process using zinc sorbent and O2 regeneration with SO2 in the regeneration product gas converted to elemental sulfur using the direct sulfur recovery process (DSRP). Material and energy balances were calculated using the process simulation package PRO/II. Major process equipment was sized and a preliminary economic analysis completed. Sorbent replacement rate, which is determined by the multicycle sorbent durability, was found to be the most significant factor in both processes. For large replacement rates corresponding to average sorbent lifetimes of 250 cycles or less, the single-stage zinc sorbent process with DSRP was estimated to be less costly. However, the cost of the two-stage cerium sorbent process was more sensitive to sorbent replacement rate, and, as the required replacement rate decreased, the economics of the two-stage process improved. For small sorbent replacement rates corresponding to average sorbent lifetimes of 1000 cycles or more, the two-stage cerium process was estimated to be less costly. In the relatively wide middle range of sorbent replacement rates, the relative economics of the two processes depends on other factors such as the unit cost of sorbents, oxygen, nitrogen, and the relative capital costs

  19. A Practical Approach for Studying Fouling Process in Li-Recovery Pilot Plant

    Science.gov (United States)

    Kong, M.; Yoon, H.; Eom, C.; Kim, B.; Chung, K.

    2011-12-01

    The efficiency of selective ion recovery such as lithium from seawater has been major interest of previous studies. However, the characterization of adsorption behavior as well as dissolution yield as discharging environmentally problematic chemical species must carefully studied in various conditions including different seawater conditions [1]. Marine biofouling communities are complex, highly dynamic ecosystems consisting of a diverse range of organisms. The development of such communities begins with bacterial attachment followed by the colonization of higher organisms such as invertebrate larvae and algal spores [2-3]. Monitoring and field studies regarding fouling problems during operation of Li-recovery pilot plant which is designed by the Korea Institute of Geoscience & Mineral Resources (KIGAM) were major concern of this study. We examined fouling process for the duration of exposure time in real marine environment. Substrated with no-antifouling treated material and antifouling treated material were exposed and tested for different behaviors toward fouling in ocean. SEM-EDS (Scanning Electron Microscope-Energy dispersive Spectroscopy) analysis was done for surface identification of specific elements for possible dissolution during seawater exposure. To identify organic compound was used GC-MS (Gas Chromatography Mass Spectrometer) analysis. Experiment results, organisms such as alga are fouled the most on 30 days and antitreated material is fouled less than non antitreated material. Operating Li-recovery pilot plant to sea, we need to consider in order to effectively and economically resolve the fouling problem. Acknowledgement : This research was supported by the national research project titled "The Development of Technology for Extraction of Resources Dissolved in Seawater" of the Korea Institute of Geoscience and Mineral Resources (KIGAM) funded by the Ministry of Land, Transport and Maritime Affairs. References [1] M. Y. Diego, K. Soren, and D. J. Kim

  20. Biologically produced sulfur

    NARCIS (Netherlands)

    Kleinjan, W.E.; Keizer, de A.; Janssen, A.J.H.

    2003-01-01

    Sulfur compound oxidizing bacteria produce sulfur as an intermediate in the oxidation of hydrogen sulfide to sulfate. Sulfur produced by these microorganisms can be stored in sulfur globules, located either inside or outside the cell. Excreted sulfur globules are colloidal particles which are stabil

  1. SULFUR POLYMER ENCAPSULATION

    International Nuclear Information System (INIS)

    Sulfur polymer cement (SPC) is a thermoplastic polymer consisting of 95 wt% elemental sulfur and 5 wt% organic modifiers to enhance long-term durability. SPC was originally developed by the U.S. Bureau of Mines as an alternative to hydraulic cement for construction applications. Previous attempts to use elemental sulfur as a construction material in the chemical industry failed due to premature degradation. These failures were caused by the internal stresses that result from changes in crystalline structure upon cooling of the material. By reacting elemental sulfur with organic polymers, the Bureau of Mines developed a product that successfully suppresses the solid phase transition and significantly improves the stability of the product. SPC, originally named modified sulfur cement, is produced from readily available, inexpensive waste sulfur derived from desulfurization of both flue gases and petroleum. The commercial production of SPC is licensed in the United States by Martin Resources (Odessa, Texas) and is marketed under the trade name Chement 2000. It is sold in granular form and is relatively inexpensive ((approx)$0.10 to 0.12/lb). Application of SPC for the treatment of radioactive, hazardous, and mixed wastes was initially developed and patented by Brookhaven National Laboratory (BNL) in the mid-1980s (Kalb and Colombo, 1985; Colombo et al., 1997). The process was subsequently investigated by the Commission of the European Communities (Van Dalen and Rijpkema, 1989), Idaho National Engineering Laboratory (Darnell, 1991), and Oak Ridge National Laboratory (Mattus and Mattus, 1994). SPC has been used primarily in microencapsulation applications but can also be used for macroencapsulation of waste. SPC microencapsulation has been demonstrated to be an effective treatment for a wide variety of wastes, including incinerator hearth and fly ash; aqueous concentrates such as sulfates, borates, and chlorides; blowdown solutions; soils; and sludges. It is not

  2. Experimental Research on Comprehensive Processing of High-Sulfur Cu-Zn Polymetallic Ore%某高硫铜锌多金属矿综合回收试验研究

    Institute of Scientific and Technical Information of China (English)

    张文翰; 李志春

    2015-01-01

    A complex high⁃sulphur Cu⁃Zn polymetallic ore is rich in a variety of valuable metallic elements, among which, copper and zinc minerals are mainly finely⁃disseminated, while pyrite is mainly of coarse grain, with a complicated dissemination among minerals. A technique consisting of coarse grinding, Cu⁃Zn asynchronous bulk flotation for tailings discarding, regrinding of rough concentrate and Cu⁃Zn separation was adopted, resulting in the copper concentrate graded 22.56% Cu at a recovery of 87.55%, and zinc concentrate graded 42.86% Zn at a recovery of 75. 64%. Shaking table was introduced to obtain high⁃grade sulfur concentrate from tailings by the process of coarse grinding⁃bulk flotation.%某复杂高硫铜锌多金属矿富含多种有价金属元素,铜、锌矿物以细粒嵌布为主,黄铁矿主要以粗粒形态存在,矿物间嵌布关系复杂。采用粗磨铜锌异步混选抛尾⁃粗精矿再磨铜锌分离选矿工艺,获得了铜精矿品位22.56%、回收率87.55%,锌精矿品位42.86%、回收率75.64%的指标,粗磨混浮尾矿用摇床重选可选出合格硫精矿。

  3. Well test analysis, application to thermal recovery processes for reservoir characterization

    OpenAIRE

    Ghahfarokhi, Ashkan Jahanbani

    2015-01-01

    Thermal recovery by steam injection is considered to be a promising method for achieving a high ultimate recovery. A composite reservoir may occur during any enhanced oil recovery (EOR) project like steam injection into an oil reservoir. Thermal falloff test analysis offers a quick way to obtain an estimate of the swept volume and steam zone properties. Most of the models used for the analysis assume two regioncomposite reservoirs with different but uniform properties separated...

  4. Asphaltene precipitation and its effects on the vapour extraction (VAPEX) heavy oil recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Luo, P.; Wang, X.; Gu, Y. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Regina Univ., SK (Canada). Petroleum Technology Research Centre; Zhang, H. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Core Laboratories Canada Ltd., Calgary, AB (Canada); Moghadam, L. [Fekete Associates Inc., Calgary, AB (Canada)

    2008-10-15

    One of the most important physical phenomena during the solvent vapour extraction (VAPEX) of heavy oil recovery is asphaltene precipitation. After the asphaltene precipitation occurs, the produced heavy oil is deasphalted in-situ, resulting in a lower viscosity and better quality. However, precipitated asphaltenes may plug some small pores of the reservoir formation, thus reducing its permeability. This paper examined the effects of three operating factors on the asphaltene precipitation during the VAPEX process, notably solvent type; operating pressure; and sand-pack permeability. Eight VAPEX tests were conducted to recover two different Lloydminster heavy oil samples from a rectangular sand-packed physical model with a butane mixture and propane as the respective solvents. The accumulative heavy oil and solvent production from the physical model were measured in the entire VAPEX process. The paper described the materials, experimental set-up, and experimental preparation. The VAPEX test was also explained. Results were presented for sand consolidation; solvent effect; pressure effect; and permeability effect. It was concluded that when the extracting solvent is in a liquid-gas state, asphaltene precipitation occurs and leads to in-situ deasphalting. 15 refs., 3 tabs., 6 figs.

  5. Recovery of Flavonoids from Orange Press Liquor by an Integrated Membrane Process

    Directory of Open Access Journals (Sweden)

    Alfredo Cassano

    2014-08-01

    Full Text Available Orange press liquor is a by-product generated by the citrus processing industry containing huge amounts of natural phenolic compounds with recognized antioxidant activity. In this work, an integrated membrane process for the recovery of flavonoids from orange press liquors was investigated on a laboratory scale. The liquor was previously clarified by ultrafiltration (UF in selected operating conditions by using hollow fiber polysulfone membranes. Then, the clarified liquor with a total soluble solids (TSS content of 10 g·100 g−1 was pre-concentrated by nanofiltration (NF up to 32 g TSS 100 g−1 by using a polyethersulfone spiral-wound membrane. A final concentration step, up to 47 g TSS 100 g−1, was performed by using an osmotic distillation (OD apparatus equipped with polypropylene hollow fiber membranes. Suspended solids were completely removed in the UF step producing a clarified liquor containing most part of the flavonoids of the original press liquor due to the low rejection of the UF membrane towards these compounds. Flavanones and anthocyanins were highly rejected by the NF membrane, producing a permeate stream with a TSS content of 4.5 g·100 g−1. An increasing of both the flavanones and anthocyanins concentration was observed in the NF retentate by increasing the volume reduction factor (VRF. The final concentration of flavonoids by OD produced a concentrated solution of interest for nutraceutical and pharmaceutical applications.

  6. INVESTIGATION OF MULTISCALE AND MULTIPHASE FLOW, TRANSPORT AND REACTION IN HEAVY OIL RECOVERY PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    Yannis C. Yortsos

    2003-02-01

    This is final report for contract DE-AC26-99BC15211. The report describes progress made in the various thrust areas of the project, which include internal drives for oil recovery, vapor-liquid flows, combustion and reaction processes and the flow of fluids with yield stress. The report consists mainly of a compilation of various topical reports, technical papers and research reports published produced during the three-year project, which ended on May 6, 2002 and was no-cost extended to January 5, 2003. Advances in multiple processes and at various scales are described. In the area of internal drives, significant research accomplishments were made in the modeling of gas-phase growth driven by mass transfer, as in solution-gas drive, and by heat transfer, as in internal steam drives. In the area of vapor-liquid flows, we studied various aspects of concurrent and countercurrent flows, including stability analyses of vapor-liquid counterflow, and the development of novel methods for the pore-network modeling of the mobilization of trapped phases and liquid-vapor phase changes. In the area of combustion, we developed new methods for the modeling of these processes at the continuum and pore-network scales. These models allow us to understand a number of important aspects of in-situ combustion, including steady-state front propagation, multiple steady-states, effects of heterogeneity and modes of combustion (forward or reverse). Additional aspects of reactive transport in porous media were also studied. Finally, significant advances were made in the flow and displacement of non-Newtonian fluids with Bingham plastic rheology, which is characteristic of various heavy oil processes. Various accomplishments in generic displacements in porous media and corresponding effects of reservoir heterogeneity are also cited.

  7. Phosphorus removal and recovery from domestic wastewater in a novel process of enhanced biological phosphorus removal coupled with crystallization.

    Science.gov (United States)

    Zou, Haiming; Wang, Yan

    2016-07-01

    A new process of enhanced biological phosphorus removal coupled with crystallization recovery of phosphorus was developed here, where the feasibility of nutrients removal and potential for phosphorus recovery from domestic wastewater was further assessed. Results showed that an excellent nutrients removal and phosphorus recovery performance was achieved, in which the averaged COD, PO4(3-)-P and NO3(-)-N removal efficiencies were 82.6%, 87.5% and 91.6%, respectively and a total of 59.3% of phosphorus was recovered as hydroxyapatite. What's more, crystallization recovery of phosphorus greatly enhanced the biological phosphorus removal efficiency. After the incorporation of the phosphorus recovery column via side-stream, the phosphorus concentration of effluent was significantly decreased ranging from 1.24mg/L to 0.85mg/L, 0.52mg/L and 0.41mg/L at the lateral flow ratios of 0, 0.1, 0.2 and 0.3, respectively. The results obtained here would be beneficial to provide a prospective alternative for phosphorus removal and recovery from wastewater. PMID:27003794

  8. The effective synthesis of Insoluble sulfur using electron beam

    International Nuclear Information System (INIS)

    Vulcanization is process that formed crosslinking by Insoluble sulfur between linear structure of rubber polymer. Recently, Synthesis of Insoluble sulfur is used Thermal polymerization using about 250 ∼ 300 .deg. C and extraction process is used carbon disulfide(CS2) for separation between soluble sulfur and insoluble sulfur. But this process isn't environmental, economical and safety. This research was focus on developing of insoluble sulfur synthesis process using electron beam. This new process is using under the 140 .deg. C. Because of that, explosion risk is decrease, environmental and economical factor is increased. The sulfur can be melt by increase temperature or made solution using carbon disulfide. And electron beam is irradiated melting sulfur or sulfur solution. After irradiation, The high purity insoluble sulfur can be obtained by separation with carbon disulfide

  9. Comparison between pre-fractionation and fractionation process of heavy gas oil for determination of sulfur compounds using comprehensive two-dimensional gas chromatography.

    Science.gov (United States)

    Machado, Maria Elisabete; Bregles, Lucas Panizzi; de Menezes, Eliana Weber; Caramão, Elina Bastos; Benvenutti, Edilson Valmir; Zini, Cláudia Alcaraz

    2013-01-25

    The separation of the organic sulfur compounds (OSC) of petroleum or its heavy fractions is a critical step and is essential for the correct characterization of these compounds, especially due to similar physical and chemical properties of polycyclic aromatic sulfur heterocycles (PASH) and polycyclic aromatic hydrocarbons (PAH). This similarity results in coelutions among PAH and PASH and for this reason former steps of fractionation are required before gas chromatographic analysis. The objective of this study was to evaluate the potential of GC×GC for the separation and identification of OSC in a heavy gas oil sample without fractionation, after pre-fractionation in an alumina column and also after fractionation process. This last one was performed with a modified stationary phase manufactured and characterized in the laboratory, called Pd(II)-MPSG, where palladium is chemically linked to silica through mercaptopropyl groups. The fractions obtained from both procedures were analyzed by GC×GC/TOFMS, which was effective to separate and identify various classes of OSC. A hundred and thirty-five compounds were tentatively identified in the sample that was only pre-fractionated. However, when the fractionation was also performed with the Pd(II)-MPSG phase, a larger number of sulfur compounds were found (317). Results have shown that the analysis of a pre-fractionated sample by GC×GC/TOFMS is suitable when the goal is a general characterization of classes of compounds in the sample, while a more detailed analysis of PASH can be performed, using also the fractionation Pd(II)-MPSG phase. GC×GC/TOFMS played a major role in the comparison of samples obtained from pre-fractionation and fractionation steps due to its high peak capacity, selectivity, organized distribution of chromatographic peaks and resolution. PMID:23298843

  10. Sulfur meter speeds coal blending

    International Nuclear Information System (INIS)

    The sulfur content has become the most important criterion that industry looks at when purchasing coal. The exact amount of sulfur in coal being processed by a preparation plant must be known and, if possible, controlled by blending coal streams of various sulfur contents. Present techniques, however, of measuring the sulfur in coal involve laborious and time-consuming sampling and chemical analysis (12 to 24 hr), and the results usually are not available until the following day. By then, the coal barges or trains are already on the way to their destinations. A new nuclear sulfur meter is expected to overcome these difficulties and help lead to true automation in coal preparation plants. Initially developed by the Bureau of Mines' Morgantown Energy Research Center (MERC) at Morgantown, W. Va., and completed after reorganization of the center by the US Energy Research and Development Administration (ERDA), the meter can scan coal to produce a reading within 2 min to an accuracy of 0.04 percent sulfur. The meter is expected to soon result in an element-ash-moisture-Btu meter that would rapidly detect the sulfur, sodium, potassium, and overall mineral content of the coal, as well as its ash and Btu content

  11. Sulfur metabolism in phototrophic sulfur bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Dahl, Christiane

    2008-01-01

    Phototrophic sulfur bacteria are characterized by oxidizing various inorganic sulfur compounds for use as electron donors in carbon dioxide fixation during anoxygenic photosynthetic growth. These bacteria are divided into the purple sulfur bacteria (PSB) and the green sulfur bacteria (GSB). They...... utilize various combinations of sulfide, elemental sulfur, and thiosulfate and sometimes also ferrous iron and hydrogen as electron donors. This review focuses on the dissimilatory and assimilatory metabolism of inorganic sulfur compounds in these bacteria and also briefly discusses these metabolisms in...... other types of anoxygenic phototrophic bacteria. The biochemistry and genetics of sulfur compound oxidation in PSB and GSB are described in detail. A variety of enzymes catalyzing sulfur oxidation reactions have been isolated from GSB and PSB (especially Allochromatium vinosum, a representative of the...

  12. A novel NGL (natural gas liquid) recovery process based on self-heat recuperation

    International Nuclear Information System (INIS)

    This study examined an innovative self-heat-recuperation technology that circulates latent and sensible heat in the thermal process and applied it to the NGL (natural gas liquid) recovery process. A CGCC (column grand composite curve) was used to assess the thermodynamic feasibility of implementing the heat pump system and self-heat-recuperation technology into a conventional distillation column. The proposed distillation based on self-heat recuperation reduced the energy consumption dramatically by compressing the effluent stream, whose temperature was increased to provide the minimum temperature difference for the heat exchanger, and circulating the stream heat in the process. According to a simulation of the proposed sequence, up to 73.43 and 83.48% of the condenser and reboiler energy, respectively, were saved compared to a conventional column. This study also proposes heat integration to improve the performance of self-heat recuperation. The results showed that the modified sequence saves up 64.35, 100.00 and 31.60% of the condenser energy requirements, reboiler energy requirements and OP (operating cost), respectively, compared to a classical heat pump system, and 90.24, 100.00, and 67.19%, respectively, compared to a conventional column. The use of these sequences to retrofit a distillation column to save energy was also considered. - Highlights: • Innovative self-heat-recuperation technology that circulates latent and sensible heat. • A CGCC (column grand composite curve) is used to assess the thermodynamic feasibility. • The proposed sequence saves up 67.19% of the OP (operating cost). • The proposed sequences can be used to retrofit a distillation column to save energy

  13. Selective leaching process for the recovery of copper and zinc oxide from copper-containing dust.

    Science.gov (United States)

    Wu, Jun-Yi; Chang, Fang-Chih; Wang, H Paul; Tsai, Ming-Jer; Ko, Chun-Han; Chen, Chih-Cheng

    2015-01-01

    The purpose of this study was to develop a resource recovery procedure for recovering copper and zinc from dust produced by copper smelting furnaces during the manufacturing of copper-alloy wires. The concentrations of copper in copper-containing dust do not meet the regulation standards defined by the Taiwan Environmental Protection Administration; therefore, such waste is classified as hazardous. In this study, the percentages of zinc and copper in the dust samples were approximately 38.4% and 2.6%, respectively. To reduce environmental damage and recover metal resources for industrial reuse, acid leaching was used to recover metals from these inorganic wastes. In the first stage, 2 N of sulphuric acid was used to leach the dust, with pH values controlled at 2.0-3.0, and a solid-to-liquid ratio of 1:10. The results indicated that zinc extraction efficiency was higher than 95%. A selective acid leaching process was then used to recover the copper content of the residue after filtration. In the second stage, an additional 1 N of sulphuric acid was added to the suspension in the selective leaching process, and the pH value was controlled at 1.5-2.0. The reagent sodium hydroxide (2 N) was used as leachate at a pH greater than 7. A zinc hydroxide compound formed during the process and was recovered after drying. The yields for zinc and copper were 86.9-93.5% and 97.0-98.9%, respectively. PMID:25191877

  14. Selective recovery of pure copper nanopowder from indium-tin-oxide etching wastewater by various wet chemical reduction process: Understanding their chemistry and comparisons of sustainable valorization processes.

    Science.gov (United States)

    Swain, Basudev; Mishra, Chinmayee; Hong, Hyun Seon; Cho, Sung-Soo

    2016-05-01

    Sustainable valorization processes for selective recovery of pure copper nanopowder from Indium-Tin-Oxide (ITO) etching wastewater by various wet chemical reduction processes, their chemistry has been investigated and compared. After the indium recovery by solvent extraction from ITO etching wastewater, the same is also an environmental challenge, needs to be treated before disposal. After the indium recovery, ITO etching wastewater contains 6.11kg/m(3) of copper and 1.35kg/m(3) of aluminum, pH of the solution is very low converging to 0 and contain a significant amount of chlorine in the media. In this study, pure copper nanopowder was recovered using various reducing reagents by wet chemical reduction and characterized. Different reducing agents like a metallic, an inorganic acid and an organic acid were used to understand reduction behavior of copper in the presence of aluminum in a strong chloride medium of the ITO etching wastewater. The effect of a polymer surfactant Polyvinylpyrrolidone (PVP), which was included to prevent aggregation, to provide dispersion stability and control the size of copper nanopowder was investigated and compared. The developed copper nanopowder recovery techniques are techno-economical feasible processes for commercial production of copper nanopowder in the range of 100-500nm size from the reported facilities through a one-pot synthesis. By all the process reported pure copper nanopowder can be recovered with>99% efficiency. After the copper recovery, copper concentration in the wastewater reduced to acceptable limit recommended by WHO for wastewater disposal. The process is not only beneficial for recycling of copper, but also helps to address environment challenged posed by ITO etching wastewater. From a complex wastewater, synthesis of pure copper nanopowder using various wet chemical reduction route and their comparison is the novelty of this recovery process. PMID:26918838

  15. Energetics and economics of the process for hydrogen recovery by means of the membranes made of palladium alloys

    International Nuclear Information System (INIS)

    This paper reports on the calculations of various technological processes using membranes made of palladium alloys that have been made. Alternative methods for hydrogen recovery have been compared. The plant for production of up to 130 kg/hr of pure hydrogen has been successfully tested

  16. 40 CFR Appendix Xiii to Part 266 - Mercury Bearing Wastes That May Be Processed in Exempt Mercury Recovery Units

    Science.gov (United States)

    2010-07-01

    ... are exempt mercury-bearing materials with less than 500 ppm of 40 CFR Part 261, appendix VIII organic... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Mercury Bearing Wastes That May Be Processed in Exempt Mercury Recovery Units XIII Appendix XIII to Part 266 Protection of...

  17. Mathematical model of a record type device for valued components recovery from end process gases of uranium hexafluoride production

    OpenAIRE

    Bereza, V. N.; Dyadik, Valery Feodosievich; Baydali, Sergey Anatolievich

    2007-01-01

    Mathematical model of the device for valued components recovery from end gases of sublimate production including hydrodynamics, thermodynamics and kinetics of interaction process of solid and gaseous phases realized in the package MATLAB has been presented. Static and dynamic characteristics of the device as a control object necessary for control algorithm synthesis are obtained and analyzed

  18. Identification of bacteria used for microbial enhanced oil recovery process by fluorescence in situ hybridization technique

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, K.; Tanaka, S.; Otsuka, M. [Kansai Research Institute, Kyoto (Japan). Lifescience Lab.; Yonebayashi, H. [Japan National Oil Corp., Chiba (Japan). Tech. Research Center; Enomoto, H. [Tohoku University, Sendai (Japan). Dept. of Geoscience and Tech.

    2000-01-01

    A fluorescence in situ hybridization (FISH) technique using 16S rRNA-targeted oligonucleotide probes was developed for rapid detection of microorganisms for use in the microbial enhancement of oil recovery (MEOR) process. Two microorganisms, Enterobacter cloacae TRC-322 and Bacillus licheniformis TRC-18-2-a, were selected from a collection of Enterobacter sp. and Bacillus sp. which were screened in previous studies as candidate microorganisms for injection, and were used for this experiment. Oligonucleotide probes, design based on specific sequences in the 16S rRNA gene were labeled with either fluorescein isothiocyanate (FITC), or 6-car-boxy-X-rhodamine (ROX), and were allowed to hybridize with fixed cells of the two microorganisms noted above. The fluorescence signal emitted from each microorganism cells could clearly be detected by an epifluorescence microscope. Moreover, E. cloacae TRC-322 and B, licheniformis TRC-18-2-a, suspended in actual reservoir brine, including inorganic salts, oil and aboriginal cells of the reservoir brine, could be detected directly by this hybridization method, without the need for cultivation and isolation. (author)

  19. Process for the recovery of tungsten in a pure form from tungsten-containing materials

    International Nuclear Information System (INIS)

    A process is described for the recovery of tungsten from tungsten-containing materials which comprises the steps of (i) admixing the tungsten-containing material with a melt at a temperature of between 6800C and 7500C. The melt consists of a salt selected from the group consisting of sodium nitrate, sodium nitrite and mixtures thereof in a substantially stoichiometrical amount to the tungsten constituent of the tungsten-containing material. This is done to disintegrate the tungsten-containing material and to form sodium tungstate, cooling the melt, and leaching the cooled melt with water to obtain an aqueous solution of sodium tungstate; (ii) admixing a solution of calcium chloride with the aqueous solution of sodium tungstate at a temperature of between 400C and 950C to form a calcium tungstate precipitate and separating the calcium tungstate; (iii) admixing the calcium tungstate with a preheated concentrated hydrochloric acid solution to form a tungstic acid precipitate and a CaCl/sub 2/ solution having a concentration of between 80 g/l and 180 g/l free HCl and separating the tungstic acid precipitate and obtaining tungstic acid which is substantially free of calcium ions, and (iv) calcining the tungstic acid to convert it to tungstic oxide and reducing the tungstic oxide to form metallic tungsten

  20. Occurrence process of unsafe act and recovery in conducting EOP under a simulated emergency

    International Nuclear Information System (INIS)

    Emergency operating procedures (EOPs) are plant procedures that direct operator actions necessary to mitigate the consequences of transients and accidents that have caused plant parameters to exceed reactor protection system set points or engineered safety feature set points, or other established limits. Therefore an EOP operation according to the EOP instruction is critical to a plant's safety after accidents. For this reason, EOPs should be developed to reduce operators' cognitive burden and to enhance operators' performance related to the EOP operation. In spite of many kinds of efforts to reduce operators' cognitive burden, it has been reported that EOPs also require operators' cognitive efforts in coping with off normal events. In Korea, we have analyzed an operator's behaviors such as error of omission (EOO) and error of commission (EOC) by noncompliance with emergency training records collected from a full scope simulator of a Westinghouse 3 loop pressurized water reactor (PWR). The simulated scenario for this study is a steam generator tube rupture immediately following a main steam line break. The purpose of this paper is to classify the occurrence process of an unsafe act by a performer and a recovery behavior observed under a simulated emergency. This result will be applied to the development of HRA (Human Reliability Analysis) data handbook and the improvement the existing HRA methodology

  1. Waste Treatment of Chrome Residue of Chromium Recovery Process Using Calcium Carbonate

    International Nuclear Information System (INIS)

    The aim of the research was to apply the precipitation technology for the treatment of aqueous wastes of leather tanning industries. The chrome liquid wastes taken was the effluent from the residue of the chromium recovery process using magnesium oxide. The precipitant used was calcium carbonate. The experiments was performed by adjusting the concentration of calcium carbonate from 50 ppm, 100 ppm, 150 ppm, 200 ppm, 250 ppm, 300 ppm, 350 ppm to 400 ppm. The stirring speed was varied from 50 rpm, 75 rpm, 100 rpm, 125 rpm, 150 rpm, 175 rpm to 200 rpm. The time of mixing was varied from 30 minutes, 60 minutes, 90 minutes, 120 minutes, 150 minutes, 175 minutes and 200 minutes. The result from the experiments lead to the best condition obtained were the concentration of precipitant was 300 ppm, flow rates of mixing was 125 rpm and time of mixing was 60 minutes. At this condition the separations efficiency of chrome obtained was 99.985%. (author)

  2. Supporting Technology for Enhanced Oil Recovery-EOR Thermal Processes Report IV-12

    Energy Technology Data Exchange (ETDEWEB)

    Izequeido, Alexandor

    2001-04-01

    This report contains the results of efforts under the six tasks of the Ninth Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections (for each of the 6 tasks) and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section. The tasks are numbered 62 through 67. The first, second, third, fourth, fifth, sixth, seventh, eight, and ninth reports on Annex IV, [Venezuela MEM/USA-DOE Fossil Energy Report IV-1, IV-2, IV-3, IV-4, IV-5, IV-6, IV-7, and IV-8 (DOE/BETC/SP-83/15, DOE/BC-84/6/SP, DOE/BC-86/2/SP, DOE/BC-87/2/SP, DOE/BC-89/1/SP, DOE/BC-90/1/SP) DOE/BC-92/1/SP, DOE/BC-93/3/SP, and DOE/BC-95/3/SP] contain the results from the first 61 tasks. Those reports are dated April 1983, August 1984, March 1986, July 1! 987, November 1988, December 1989, October 1991, February 1993, and March 1995 respectively.

  3. Evaluation of an Anaerobic Digestion System for Processing CELSS Crop Residues for Resource Recovery

    Science.gov (United States)

    Strayer, R. F.; Finger, B. W.; Alazraki, M. P.

    1997-01-01

    Three bioreactors, connected in series, were used to process CELSS potato residues for recovery of resources. The first stage was an anaerobic digestor (8 L working volume; cow rumen contents inoculum; fed-batch; 8 day retention time; feed rate 25 gdw/day) that converted 33% of feed (dry weight loss) to CO2 and "volatile fatty acids" (vfa, 83:8:8 mmolar ratio acetic:propionic:butyric). High nitrate-N in the potato residue feed was absent in the anaerobic effluent, with a high portion converted to NH4(+)-N and the remainder unaccounted and probably lost to denitrification and NH4(+) volatilization. Liquid anaerobic effluent was fed to an aerobic, yeast biomass production vessel (2 L volume; Candida ingens inoculum; batch [pellicle] growth; 2 day retention time) where the VFAs and some NH4(+)-N were converted into yeast biomass. Yeast yields accounted for up to 8% of potato residue fed into the anaerobic bioreactor. The third bioreactor (0.5 L liquid working volume; commercial nitrifier inoculum; packed-bed biofilm; continuous yeast effluent feed; recirculating; constant volume; 2 day hydraulic retention time) was used to convert successfully the remaining NH4(+)-N into nitrate-N (preferred form of N for CELSS crop production) and to remove the remaining degradable soluble organic carbon. Effluents from the last two stages were used for partial replenishment of minerals for hydroponic potato production.

  4. Lunar Sulfur Capture System

    Science.gov (United States)

    Berggren, Mark; Zubrin, Robert; Bostwick-White, Emily

    2013-01-01

    The Lunar Sulfur Capture System (LSCS) protects in situ resource utilization (ISRU) hardware from corrosion, and reduces contaminant levels in water condensed for electrolysis. The LSCS uses a lunar soil sorbent to trap over 98 percent of sulfur gases and about two-thirds of halide gases evolved during hydrogen reduction of lunar soils. LSCS soil sorbent is based on lunar minerals containing iron and calcium compounds that trap sulfur and halide gas contaminants in a fixed-bed reactor held at temperatures between 250 and 400 C, allowing moisture produced during reduction to pass through in vapor phase. Small amounts of Earth-based polishing sorbents consisting of zinc oxide and sodium aluminate are used to reduce contaminant concentrations to one ppm or less. The preferred LSCS configuration employs lunar soil beneficiation to boost concentrations of reactive sorbent minerals. Lunar soils contain sulfur in concentrations of about 0.1 percent, and halogen compounds including chlorine and fluorine in concentrations of about 0.01 percent. These contaminants are released as gases such as H2S, COS, CS2,HCl, and HF during thermal ISRU processing with hydrogen or other reducing gases. Removal of contaminant gases is required during ISRU processing to prevent hardware corrosion, electrolyzer damage, and catalyst poisoning. The use of Earth-supplied, single-use consumables to entirely remove contaminants at the levels existing in lunar soils would make many ISRU processes unattractive due to the large mass of consumables relative to the mass of oxygen produced. The LSCS concept of using a primary sorbent prepared from lunar soil was identified as a method by which the majority of contaminants could be removed from process gas streams, thereby substantially reducing the required mass of Earth-supplied consumables. The LSCS takes advantage of minerals containing iron and calcium compounds that are present in lunar soil to trap sulfur and halide gases in a fixedbed reactor

  5. Optimization of process parameters by Taguchi method in the recovery of lactose from whey using sonocrystallization

    Energy Technology Data Exchange (ETDEWEB)

    Patel, S.R.; Murthy, Z.V.P. [Chemical Engineering Department, S. V. National Institute of Technology, Surat - 395 007, Gujarat (India)

    2010-07-15

    Anti-solvent crystallization of lactose in the presence of ultrasound will reduce crystal size and the level of agglomeration as compared to the commercial cooling crystallization. It offers a potential route to enhance the physical properties as well as the rapid recovery of lactose. Since lactose recovery itself can reduce biological oxygen demand of whey by more then 80%, recovery of lactose from dairy waste stream (whey) solves the problems of dairy industries by improving economics of whey utilization and pollution reduction. In the present study, recovery of lactose from partially deproteinated whey using an anti-solvent (acetone) by sonocrystallization was optimized for finding the most influencing operating parameters; such as sonication time, anti-solvent concentration, initial lactose concentration in the whey and initial pH of sample mixture at three levels using L{sub 9}-orthogonal method. The responses were analyzed for recovery of lactose from whey. The anti-solvent concentration and the sonication time were found to be most influencing parameters for the recovery of lactose and the recovery of lactose was found to be 89.03% at the identified optimized level. The crystal size distribution of recovered lactose was found to be narrower (2.5 - 6.5 {mu}m) as compared to the commercial lactose crystals (3.5 - 9.5 {mu}m). (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Synthesis gas demonstration plant program, Phase I. Trade-off study VI, by-product sales analysis. Part 1. Sulfur recovery system. Part 2. Carbon dioxide, fly ash, bottom ash and slag

    Energy Technology Data Exchange (ETDEWEB)

    1979-03-01

    The objectives of this study were to develop and analyze information to facilitate decision making in regard to by-products from the Commercial Plant. Part 1 of the study investigated the alternative marketing and commercial advantages of producing elemental sulfur or sulfuric acid, the findings to be used with results of a technical and economic analysis to determine the relative desirability of choosing either as a by-product. The principal commercial and marketing input for this portion of the study were provided by review of authoritative published material and by personnel interviews with government, trade association and commercial information sources, including a limited number of major consumers and producers. Compilation and analysis of statistical data and knowledgeable opinions on the following were included: production and consumption trends and future outlook; levels of current and expected future prices; end-use trends and outlook for new uses; geographic consumption patterns; export market and outlook for foreign sales; and other factors related to the present and future supply and demand and effective marketing of the by-products. Technical data were obtained from the commercial suppliers of the processes involved, supplemented by information from producers of the by-products under consideration. The predicted composition and quantity of all gaseous waste streams were used for investigation of by-product potential. Capital investment and operating costs to produce the saleable by-products investigated were developed for each production alternative considered. Operating profits were determined and comparative figures were calculated for net cash flow and return on investment.

  7. Natural stone muds as secondary raw materials: towards a new sustainable recovery process

    Science.gov (United States)

    Zichella, Lorena; Tori, Alice; Bellopede, Rossana; Marini, Paola

    2016-04-01

    The production of residual sludge is a topical issue, and has become essential to recover and reuse the materials, both for the economics and the environmental aspect. According to environmental EU Directives, in fact ,the stone cutting and processing should characterized by following objectives, targets and actions: the reduction of waste generated, the decreasing of use of critical raw material, the zero landfilling of sludge and decreasing in potential soil contamination, the prevention of transport of dangerous waste, the reduction of energy consumption, the zero impact on air pollution and the cost reduction . There are many industrial sector in which residual sludge have high concentrations of metals and/or elements deemed harmful and therefore hazardous waste. An important goal, for all industrial sectors, is an increase in productivity and a parallel reduction in costs. The research leads to the development of solutions with an always reduced environmental impact. The possibility to decrease the amount of required raw materials and at the same time the reduction in the amount of waste has become the aim for any industrial reality. From literature there are different approaches for the recovery of raw and secondary materials, and are often used for the purpose chemical products that separate the elements constituting the mud but at the same time make additional pollutants. The aim of the study is to find solutions that are environmentally sustainable for both industries and citizens. The present study is focused on three different Piedmont rocks: Luserna, Diorite from Traversella and Diorite from Vico, processed with three different stone machining technologies: cutting with diamond wire in quarry (blocks), in sawmill (slabs) and surface polishing. The steps are: chemical analysis, particle size analysis and mineralogical composition and characterization of the sludge obtained from the various machining operations for the recovery of the metal material by

  8. Comparative Aspects of Sulfur Mineralization in Sediments of a Eutrophic Lake Basin †

    OpenAIRE

    Gary M King; Klug, M. J.

    1982-01-01

    The net mineralization of organic sulfur compounds in surface sediments of Wintergreen Lake was estimated from a mass-balance budget of sulfur inputs and sediment sulfur concentrations. The net mineralization of organic sulfur inputs is 80% of total sulfur) in sediment. Although sediment sulfur is predominantly organic, sulfate reduction is the most significant process in terms of the quantities of sulfur transformed in surface sediments. Rates of sulfate reduction in these sediments average ...

  9. Sulfur isotope ratios and the origins of the aerosols and cloud droplets in California stratus

    OpenAIRE

    Ludwig, F. L.

    2011-01-01

    Marine aerosols often have sulfur-to-chloride ratios greater than that found in seawater. Sulfur isotope ratios (34S/32S) were measured in aerosol and cloud droplet samples collected in the San Francisco Bay Area in an attempt to understand the processes that produce the observed sulfur-to-chloride ratios. Seawater sulfur usually has very high sulfur isotope ratios; fossil fuel sulfur tends to have smaller isotope ratios and sulfur of bacteriogenic origin still smaller. Samples collected in u...

  10. A sustainable process for the recovery of valuable metals from spent lithium-ion batteries.

    Science.gov (United States)

    Fan, Bailin; Chen, Xiangping; Zhou, Tao; Zhang, Jinxia; Xu, Bao

    2016-05-01

    In this work, an eco-friendly and hydrometallurgical process for the recovery of cobalt and lithium from spent lithium-ion batteries has been proposed, which includes pretreatment, citric acid leaching, selective chemical precipitation and circulatory leaching. After pretreatment (manual dismantling, N-methyl pyrrolidone immersion and calcination), Cu and Al foils are recycled directly and the cathode active materials are separated from the cathode efficiently. Then, the obtained cathode active materials (waste LiCoO2) was firstly leached with 1.25 mol l(-1) citric acid and 1 vol.% H2O2 solution. Then cobalt was precipitated using oxalic acid (H2C2O4) under a molar ratio of 1:1.05 (H2C2O4: Co(2+)). After filtration, the filtrate (containing Li(+)) and H2O2 was employed as a leaching agent and the optimum conditions are studied in detail. The leaching efficiencies can reach as high as 98% for Li and 90.2% for Co, respectively, using filter liquor as leaching reagent under conditions of leaching temperature of 90°C, 0.9 vol.% H2O2 and a solid-to-liquid ratio of 60 ml g(-1) for 35 min. After three bouts of circulatory leaching, more than 90% Li and 80% Co can be leached under the same leaching conditions. In this way, Li and Co can be recovered efficiently and waste liquor re-utilization is achievable with this hydrometallurgical process, which may promise both economic and environmental benefits. PMID:26951340

  11. Study on Leaching Process of Germanium Fly Ash with Sulfuric Acid%含锗烟尘的硫酸浸出工艺研究

    Institute of Scientific and Technical Information of China (English)

    郑东升; 肖松; 梁杰

    2012-01-01

    为简化含锗烟尘浸出过程,提出一段硫酸浸出工艺。浸出工艺条件为:浸出温度90℃,初始硫酸质量浓度120g/L,液固比8mL/g,浸出时间2.5h,搅拌转速120r/min。在该条件下,锌、锗浸出率分别为99.1%和87.61%左右,最终硫酸质量浓度约34.80g/L。去除不溶性锗后,锗浸出率可达到97.21%。%To simplify the leaching process of germanium fly ash, the one stage sulfuric acid leaching process was studied. The result shows the leaching processing as following: leaching temperature 90℃ initial sulfuric acid concentration 120 g/L, ratio of hquid to solid 5 mL/g, leaching time 2 h, and mixing speed 120 r/min. Under these conditions, the leaching rates of Zn and Ge were about 99.1% and 87.61%, and the concentration of end acid is about 34.80 g/L, and by removal of insoluble germanium, the leaching rate of Germanium could be about 97.21%. Zinc and Germanium can be effectively leached from Germanium fly ash in the leaching process, and the leaching technique is effective and stable.

  12. Eco-friendly copper recovery process from waste printed circuit boards using Fe3+/Fe2+ redox system

    International Nuclear Information System (INIS)

    Highlights: • We developed an ecofriendly mediated electrochemical process for copper recovery. • The recovery of copper was achieved without mechanical pretreatment of the samples. • We identified the optimal flow rate for the leaching and electrowinning of copper. • The copper content of the obtained cathodic deposits was over 99.9%. - Abstract: The present study aimed at developing an original and environmentally friendly process for the recovery of copper from waste printed circuit boards (WPCBs) by chemical dissolution with Fe3+ combined with the simultaneous electrowinning of copper and oxidant regeneration. The recovery of copper was achieved in an original set-up consisting of a three chamber electrochemical reactor (ER) connected in series with a chemical reactor (CR) equipped with a perforated rotating drum. Several experiments were performed in order to identify the optimal flow rate for the dissolution of copper in the CR and to ensure the lowest energy consumption for copper electrodeposition in the ER. The optimal hydrodynamic conditions were provided at 400 mL/min, leading to the 75% dissolution of metals and to a low specific energy consumption of 1.59 kW h/kg Cu for the electrodeposition process. In most experiments, the copper content of the obtained cathodic deposits was over 99.9%

  13. Conference on microbiological processes useful in enhanced oil recovery. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-10-01

    Six formal presentations were made at the meeting, followed by four workshops dealing with specific topics: bioengineering, reservoir ecology and environment, transformations, and bioproducts. All were related to microbial enhancement of oil recovery. (DLC)

  14. Interlock recovery during the drying, calcination and vitrification phase of Am/Cm processing

    International Nuclear Information System (INIS)

    This document summarizes the results of five CIM5 [5-inch Cylindrical Induction Melter] runs designed to demonstrate power interlock recovery methods during the drying, calcination and vitrification phases of the Am/Cm melter cycle

  15. Recovery of copper and lead from waste printed circuit boards by supercritical water oxidation combined with electrokinetic process

    International Nuclear Information System (INIS)

    An effective and benign process for copper and lead recovery from waste printed circuit boards (PCBs) was developed. In the process, the PCBs was pre-treated in supercritical water, then subjected to electrokinetic (EK) process. Experimental results showed that supercritical water oxidation (SCWO) process was strong enough to decompose the organic compounds of PCBs, and XRD spectra indicated that copper and lead were oxidized into CuO, Cu2O and β-PbO2 in the process. The optimum SCWO treatment conditions were 60 min, 713 K, 30 MPa, and EK treatment time, constant current density were 11 h, 20 mA cm-2, respectively. The recovery percentages of copper and lead under optimum SCWO + EK treatment conditions were around 84.2% and 89.4%, respectively. In the optimized EK treatment, 74% of Cu was recovered as a deposit on the cathode with a purity of 97.6%, while Pb was recovered as concentrated solutions in either anode (23.1%) or cathode (66.3%) compartments but little was deposited on the electrodes. It is believed that the process is effective and practical for Cu and Pb recovery from waste electric and electronic equipments.

  16. Effect of sulfidogenesis cycling on the biogeochemical process in arsenic-enriched aquifers in the Lanyang Plain of Taiwan: Evidence from a sulfur isotope study

    Science.gov (United States)

    Kao, Yu-Hsuan; Liu, Chen-Wuing; Wang, Pei-Ling; Liao, Chung-Min

    2015-09-01

    This study evaluated the biogeochemical interactions between arsenic (As) and sulfur (S) in groundwater to understand the natural and anthropogenic influences of S redox processes on As mobilization in the Lanyang Plain, Taiwan. Cl- and the sulfate isotopic composition (δ34S[SO4]) were selected as conservative tracers. River water and saline seawater were considered as end members in the binary mixing model. Thirty-two groundwater samples were divided into four types of groundwater (I, pyrite-oxidation; II, iron- and sulfate-reducing; III, sulfate-reducing; and IV, anthropogenic and others). The binary mixing model coupled with discriminant analysis was applied to yield a classification with 97% correctness, indicating that the DO/ORP values and δ34S[SO4] and Fe2+ concentrations are effective redox-sensitive indicators. Type I groundwater is mostly located in a mountainous recharge area where pyrite oxidation is the major geochemical process. A high 18O enrichment factor (ε[SO4-H2O]) and high 34S enrichment factor (ε34S[FeS2-SO4]) indicate that disproportionation and dissimilatory sulfate reduction are both involved in Type II and Type III groundwater. The process of bacterial sulfate reduction may coprecipitate and sequester As, a mechanism that is unlikely to occur in Type II groundwater. The presence of high As and Fe2+ concentrations and enriched δ34S[SO4] in Type II groundwater suggest that biogeochemical reactions occurred under anaerobic conditions. The reductive dissolution of As-bearing Fe oxyhydroxides together with microbial disproportionation of sulfur explains the substantial correlations among the high As concentration and enriched δ34S[SO4] and Fe2+ concentrations in the iron- and sulfate-reducing zone (Type II). The As concentration in Type III groundwater (sulfate-reducing) is lower than that in Type II groundwater because of bacterial sulfate reduction and coprecipitation with As. Furthermore, the dissolution of sulfate minerals is not the

  17. A COMBINED REACTION/PRODUCT RECOVERY PROCESS FOR THE CONTINUOUS PRODUCTION OF BIODIESEL

    Energy Technology Data Exchange (ETDEWEB)

    Birdwell, J.F., Jr.; McFarlane, J.; Schuh, D.L.; Tsouris, C; Day, J.N. (Nu-Energie, LLC); Hullette, J.N. (Nu-Energie, LLC)

    2009-09-01

    Oak Ridge National Laboratory (ORNL) and Nu-Energie, LLC entered into a Cooperative Research And Development Agreement (CRADA) for the purpose of demonstrating and deploying a novel technology for the continuous synthesis and recovery of biodiesel from the transesterification of triglycerides. The focus of the work was the demonstration of a combination Couette reactor and centrifugal separator - an invention of ORNL researchers - that facilitates both product synthesis and recovery from reaction byproducts in the same apparatus. At present, transesterification of triglycerides to produce biodiesel is performed in batch-type reactors with an excess of a chemical catalyst, which is required to achieve high reactant conversions in reasonable reaction times (e.g., 1 hour). The need for long reactor residence times requires use of large reactors and ancillary equipment (e.g., feed and product tankage), and correspondingly large facilities, in order to obtain the economy of scale required to make the process economically viable. Hence, the goal of this CRADA was to demonstrate successful, extended operation of a laboratory-scale reactor/separator prototype to process typical industrial reactant materials, and to design, fabricate, and test a production-scale unit for deployment at the biodiesel production site. Because of its ease of operation, rapid attainment of steady state, high mass transfer and phase separation efficiencies, and compact size, a centrifugal contactor was chosen for intensification of the biodiesel production process. The unit was modified to increase the residence time from a few seconds to minutes*. For this application, liquid phases were introduced into the reactor as separate streams. One was composed of the methanol and base catalyst and the other was the soy oil used in the experiments. Following reaction in the mixing zone, the immiscible glycerine and methyl ester products were separated in the high speed rotor and collected from separate

  18. A COMBINED REACTION/PRODUCT RECOVERY PROCESS FOR THE CONTINUOUS PRODUCTION OF BIODIESEL

    International Nuclear Information System (INIS)

    Oak Ridge National Laboratory (ORNL) and Nu-Energie, LLC entered into a Cooperative Research And Development Agreement (CRADA) for the purpose of demonstrating and deploying a novel technology for the continuous synthesis and recovery of biodiesel from the transesterification of triglycerides. The focus of the work was the demonstration of a combination Couette reactor and centrifugal separator - an invention of ORNL researchers - that facilitates both product synthesis and recovery from reaction byproducts in the same apparatus. At present, transesterification of triglycerides to produce biodiesel is performed in batch-type reactors with an excess of a chemical catalyst, which is required to achieve high reactant conversions in reasonable reaction times (e.g., 1 hour). The need for long reactor residence times requires use of large reactors and ancillary equipment (e.g., feed and product tankage), and correspondingly large facilities, in order to obtain the economy of scale required to make the process economically viable. Hence, the goal of this CRADA was to demonstrate successful, extended operation of a laboratory-scale reactor/separator prototype to process typical industrial reactant materials, and to design, fabricate, and test a production-scale unit for deployment at the biodiesel production site. Because of its ease of operation, rapid attainment of steady state, high mass transfer and phase separation efficiencies, and compact size, a centrifugal contactor was chosen for intensification of the biodiesel production process. The unit was modified to increase the residence time from a few seconds to minutes*. For this application, liquid phases were introduced into the reactor as separate streams. One was composed of the methanol and base catalyst and the other was the soy oil used in the experiments. Following reaction in the mixing zone, the immiscible glycerine and methyl ester products were separated in the high speed rotor and collected from separate

  19. Development of a coupling process heat exchanger between a VHTR and a sulfur-iodine hydrogen production system - HTR2008-58071

    International Nuclear Information System (INIS)

    A heat exchanger to transfer the heat generated from a nuclear reactor to a sulfur-iodine hydrogen production system has been developed. This heat exchanger operates in the extreme environments of a high corrosion, a high temperature, and a high differential pressure. A coating and ion beam mixing surface modification technology are applied to the process heat exchanger in order to enhance its corrosion resistance without loosing the manufacturability of the metal. A Ni-based super alloy is coated with a silicon carbide to enhance its corrosion resistance. The development of heat exchanger including shape design, thermal sizing, ion beam mixing process, stress analysis, and the manufacturing of small scale mock-up heat exchanger are discussed in this paper. The heat exchanger is a hybrid type to meet the design pressure requirements between a nuclear system and a hydrogen production system. A thermal sizing procedure for the process heat exchanger by considering the heat of sulfuric acid gas decomposition is developed. A finite element stress analysis is carried out by using the temperature profile obtained from the thermal sizing calculation. The finite element models were studied to simulate the stress state of the heat exchanger. Two-dimensional analysis was performed at the entrance region of the heat exchanger. A three-dimensional analysis for a single effective heat transfer channel was performed to investigate three-dimensional stress state. Stress analysis results have shown that the developed heat exchanger can withstand the required pressure difference at the elevated temperature condition. A small size heat exchanger was fabricated in order to test it in a high temperature nitrogen-gas loop. The fabrication of the heat exchanger includes a machining of the flow path, a coating and ion beam mixing, and a diffusion bonding of the heat transfer plate. (authors)

  20. Advanced sulfur control concepts in hot-gas desulfurization technology. Quarterly report, April--June 1994

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, D.P.

    1994-07-01

    The primary objective of this research project is the direct production of elemental sulfur during the regeneration of known high temperature desulfurization sorbents. The contract was awarded to LSU on April 12, 1994, and this quarterly report covers accomplishments during the first 2 1/2 months of the project. Effort during the initial 2 1/2 month period has been limited to Tasks 1 and 2, and involves a search of the literature to identify concepts for producing elemental sulfur during regeneration of known metal oxide sorbents and a thermodynamic evaluation of these concepts. While searching and evaluating the literature is a continuing process, concentrated effort on that phase is now complete and a detailed summary is included in this report. Three possible concepts for the direct production of elemental sulfur were identified in the LSU proposal, and the literature search has not uncovered any additional concepts. Thus, the three concepts being investigated involve: (1) regeneration with SO{sub 2}, (2) regeneration with mixtures Of 02 and H{sub 2}O, and (3) regeneration with H{sub 2}O. While concept (3) directly produces H{sub 2}S instead of elemental sulfur, the concept is included because the possibility exists for converting H{sub 2}S to elemental sulfur using the Claus process. Each of the concepts will ultimately be compared to the Direct Sulfur Recovery Process (DSRP) under development by RTI. DSRP involves initial sorbent regeneration to SO{sub 2}, and the inclusion of additional processing steps to reduce the SO{sub 2} to elemental sulfur.