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Process Considerations in the Biodesulfurization of Crude Oil

Description: Biodesulfurization offers an attractive alternative to conventional hydrodesulfurization due to the mild operating conditions and reaction specificity afforded by the biocatalyst. The enzymatic pathway existing in Rhodococcus has been demonstrated to oxidatively desulfhrize the organic sulfbr occurring in dibenzothiophene while leaving the hydrocarbon intact. In order for biodesulfiization to realize commercial success, a variety of process considerations must be addressed including reaction rate, emulsion formation and breakage, biocatalyst recovery, and both gas and liquid mass transport. This study compares batch stirred to electro-spray bioreactors in the biodesulfurization of both model organics and actual crudes in terms of their operating costs, ability to make and break emulsions, ability to effect efficient reaction rates and enhance mass transport. Further, sulfim speciation in crude oil is assessed and compared to the sulfur specificity of currently available biocatalyst.
Date: October 20, 1998
Creator: Borole, A.P. & Kaufman, E.N.
Partner: UNT Libraries Government Documents Department

Improving Enzyme Activity and Broadening Selectivity for Biological Desulfurization and Upgrading of Petroleum Feedstocks

Description: The objective of this project was to develop improved biocatalysts for desulfurization and upgrading of petroleum feedstocks. The goal was to improve the activity and broaden the selectivity of desulfurization enzymes using directed evolution as a tool as well as to explore the impact of ring-opening on biological desulfurization
Date: May 12, 2003
Creator: Borole, Abhijeet P.; Hamilton, Choo Y.; Miller, Karen; Davison, Brian; Grossman, Matthew & Shong, Robert
Partner: UNT Libraries Government Documents Department

A NOVEL APPROACH TO CATALYTIC DESULFURIZATION OF COAL

Description: Efforts toward quantitation of the sulfur removed from coal in the reaction Coal(S) + excess PBu3 {yields}heat Coal + SPBu3 /PBu3 by column chromatography of the products followed by weighing the SPBu3 and vacuum distillation of the SPBu3/PBu3 mixture followed by gas chromatographic analysis are described. The first method failed, but the latter is more successful. It has been discovered that para-chloro phenol catalyzes the removal of sulfur from dibenzothiophene by PBu3 under mild conditions.
Date: May 31, 1996
Partner: UNT Libraries Government Documents Department

Stability of Sulfur Capacity Attributed to Zinc Sulfidation on Sorbent Containing Zinc Ferrite-Silica Composite Powder in Pressurized Coal Gas

Description: This paper describes an attempt to divide the total sulfur capacity into its contribution from zinc and iron using a pressurized-type thermobalance. The methodology to estimate the sulfur capacities corresponding to zinc and iron was applied to evaluate the variation in performance during multiple-cycle desulfurization. Primary objective of this paper is providing information on the stability of zinc-related sulfur capacity, which is essentially important to the sulfur removal performance at the concentration of the part-per-million level.
Date: September 19, 2002
Creator: Kobayashi, M.; Shirai, H. & Nunokawa, M.
Partner: UNT Libraries Government Documents Department

Design and Control of Hot-Gas Desulfurization Systems with High Oxygen Regenerator Feed Gas

Description: This paper studies the use of regenerator feeds that have higher oxygen concentrations. Not only steady-state but also dynamic issues are examined. The key issue is identified to be heat-removal limitations which is confirmed by dynamic simulations.
Date: September 20, 2002
Creator: Yi, C-K. & Luyben, W.L.
Partner: UNT Libraries Government Documents Department

Physical Parameters in Synthoil Process, Quarterly Report: October-December 1975

Description: This work is being done in support of the development of processes for converting coal to liquid fuel of low sulfur content, suitable for use in power production. Most of the effort is intended to produce information applicable to the SYNTHOIL Process. In the SYNTHOIL Process for converting coal to a low-sulfur fuel oil, coal is liquefied and hydro-desulfurized in a turbulent-flow, catalytic packed-bed reactor. A slurry of coal in recycled oil is reacted with hydrogen at 450 degrees C and 2,000 to 4,000 psi in the presence of Co-MoSiO2-Al2O3 catalyst. The turbulent flow of fluid prevents the coal's mineral matter from settling and plugging the reactor. The gross liquid products are centrifuged to remove the unreacted solids. The centrifuged liquid product is a low-S, low-ash fuel. The following four tasks are included: (1) heat of reaction of hydrogen with coal slurries; (2) heat transfer coefficient; (3) additives to facilitate separation of solids from liquids; and (4) catalyst testing. These are now in the planning stage of development.
Date: 1976
Creator: Fischer, J.; Lo, R.; Nandi, S.; Fredrickson, D.; Bump, T. R.; Mulcahey, T. P. et al.
Partner: UNT Libraries Government Documents Department

Adsorption and Ultrasound-Assisted Sorbent Regeneration

Description: This work was conducted for the department of Energy. In this work, we developed a class of new sorbents that were highly sulfur selective and had high sulfur capacities. The study consisted of two sections. Development of the new sorbents is described in Section 1, and Section was a fundamental study, conducted for a better understanding for desulfurization of jet fuels. More details of the results are given blow separately for the two sections.
Date: September 30, 2006
Creator: Wang, Yuhe; Ma, Liping & Yang, Ralph T.
Partner: UNT Libraries Government Documents Department

High SO2 Removal Efficiency Testing

Description: This document provides a discussion of the technical progress on DOE/PETC project number DE-AC22-92PC91338, "High Efficiency SO2 Removal Testing", for the time period 1 January through 31 March 1997. The project involves testing at six full-scale utility flue gas desulfurization (FGD) systems, to evaluate low capital cost upgrades that may allow these systems to achieve up to 98% SO2 removal efficiency. The upgrades being evaluated mostly involve using performance additives in the FGD systems. The "base" project involved testing at the Tampa Electric Company�s Big Bend Station. All five potential options to the base program have been exercised by DOE, involving testing at Hoosier Energy�s Merom Station (Option I), Southwestern Electric Power Company�s Pirkey Station (Option II), PSI Energy�s Gibson Station (Option III), Duquesne Light�s Elrama Station (Option IV), and New York State Electric and Gas Corporation�s (NYSEG) Kintigh Station (Option V). The originally planned testing has been completed for all six sites. However, additional testing is planned at the Big Bend Station. The remainder of this document is divided into four sections. Section 2, Project Summary, provides a brief overview of the status of technical efforts on this project. Section 3, Results, summarizes the outcome from technical efforts during the quarter, or results from prior quarters that have not been previously reported. In Section 4, Plans for the Next Reporting Period, an overview is provided of the technical efforts that are anticipated for the second quarter of calendar year 1997. Section 5 contains a brief acknowledgement.
Date: April 23, 1997
Creator: Blythe, Gary
Partner: UNT Libraries Government Documents Department

ADVANCED SULFUR CONTROL CONCEPTS FOR HOT-GAS DESULFURIZATION TECHNOLOGY

Description: This research project examined the feasibility of a second generation high-temperature coal gas desulfurization process in which elemental sulfur is produced directly during the sorbent regeneration phase. Two concepts were evaluated experimentally. In the first, FeS was regenerated in a H2O-O2 mixture. Large fractions of the sulfur were liberated in elemental form when the H2O-O2 ratio was large. However, the mole percent of elemental sulfur in the product was always quite small (<<1%) and a process based on this concept was judged to be impractical because of the low temperature and high energy requirements associated with condensing the sulfur. The second concept involved desulfurization using CeO2 and regeneration of the sulfided sorbent, Ce2O2S, using SO2 to produce elemental sulfur directly. No significant side reactions were observed and the reaction was found to be quite rapid over the temperature range of 500°C to 700°C. Elemental sulfur concentrations (as S2) as large as 20 mol% were produced. Limitations associated with the cerium sorbent process are concentrated in the desulfurization phase. High temperature and highly reducing coal gas such as produced in the Shell gasification process are required if high sulfur removal efficiencies are to be achieved. For example, the equilibrium H2S concentration at 800°C from a Shell gas in contact with CeO2 is about 300 ppmv, well above the allowable IGCC specification. In this case, a two-stage desulfurization process using CeO2 for bulk H2S removal following by a zinc sorbent polishing step would be required. Under appropriate conditions, however, CeO2 can be reduced to non-stoichiometric CeOn (n<2) which has significantly greater affinity for H2S. Pre-breakthrough H2S concentrations in the range of 1 ppmv to 5 ppmv were measured in sulfidation tests using CeOn at 700°C in highly reducing gases, as measured by equilibrium O2 concentration, comparable to the Shell gas. Good sorbent ...
Date: October 31, 1998
Creator: ORTIZ, A. LOPEZ; HARRISON, D.P.; GROVES, F.R.; WHITE, J.D.; ZHANG, S.; HUANG, W.-N. et al.
Partner: UNT Libraries Government Documents Department

Bioprocessing of crude oils and desulfurization using electro-spray reactors

Description: Biological removal of organic sulfur from petroleum feedstocks offers an attractive alternative to conventional thermochemical treatment due to the mild operating conditions afforded by the biocatalyst. Electro-spray bioreactors were investigated for use in desulfurization due to their reported operational cost savings relative to mechanically agitated reactors and their capability of forming emulsions < 5 {micro}m. Here, the rates dibenzothiophene (DBT) oxidation to 2-hydroxybiphenyl (2-HBP) in hexadecane, by Rhodococcus sp. IGTS8 are compared in the two reactor systems. Desulfurization rates ranged from 1.0 and 5.0 mg 2-HBP/(dry g cells-h), independent of the reactor employed. The batch stirred reactor was capable of forming a very fine emulsion in the presence of the biocatalyst IGTS8, similar to that formed in the electro-spray reactors, presumably due to the fact that the biocatalyst produces its own surfactant. While electro-spray reactors did not prove to be advantageous for the IGTS8 desulfurization system, it may prove advantageous for systems which do not produce surface-active bioagents in addition to being mass transport limited.
Date: July 1, 1998
Creator: Kaufman, E. N. & Borole, A. P.
Partner: UNT Libraries Government Documents Department

Induced biochemical interactions in immature and biodegraded heavy crude oils

Description: Studies in which selective chemical markers have been used to explore the mechanisms by which biocatalysts interact with heavy crude oils have shown that the biochemical reactions follow distinct trends. The term biocatalyst refers to a group of extremophilic microorganisms which, under the experimental conditions used, interact with heavy crude oils to (1) cause a redistribution of hydrocarbons, (2) cause chemical changes in oil fractions containing sulfur compounds and lower the sulfur content, (3) decrease organic nitrogen content, and (4) decrease the concentration of trace metals. Current data indicate that the overall effect is due to simultaneous reactions yielding products with relatively higher concentration of saturates and lower concentrations of aromatics and resins. The compositional changes depend on the microbial species and the chemistry of the crudes. Economic analysis of a potential technology based on the available data indicate that such a technology, used in a pre-refinery mode, may be cost efficient and promising. In the present paper, the background of oil biocatalysis and some recent results will be discussed.
Date: November 1, 1998
Creator: Premuzic, E.T.; Lin, M.S.; Bohenek, M.; Joshi-Tope, G.; Shelenkova, L. & Zhou, W.M.
Partner: UNT Libraries Government Documents Department

ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY

Description: The objective of this project is to develop a hot-gas desulfurization process scheme for control of H{sub 2}S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct.
Date: April 1, 1999
Partner: UNT Libraries Government Documents Department

ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY

Description: The objective of this project is to develop a hot-gas desulfurization process scheme for control of H{sub 2}S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct.
Date: July 1, 1999
Partner: UNT Libraries Government Documents Department

ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY

Description: The objective of this project is to develop a hot-gas desulfurization process scheme for control of H<sub>2</sub>S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct. The Direct Sulfur Recovery Process (DSRP), a leading process for producing an elemental sulfur byproduct in hot-gas desulfurization systems, incurs a coal gas use penalty, because coal gas is required to reduce the SO<sub>2</sub> in regeneration off-gas to elemental sulfur. Alternative regeneration schemes, which avoid coal gas use and produce elemental sulfur, will be evaluated. These include (i) regeneration of sulfided sorbent using SO<sub>2</sub> ; (ii) partial oxidation of sulfided sorbent in an O<sub>2</sub> starved environment; and (iii) regeneration of sulfided sorbent using steam to produce H<sub>2</sub>S followed by direct oxidation of H<sub>2</sub>S to elemental sulfur. Known regenerable sorbents will be modified to improve the feasibility of the above alternative regeneration approaches. Performance characteristics of the modified sorbents and processes will be obtained through lab- and bench-scale testing. Technical and economic evaluation of the most promising processes concept(s) will be carried out.
Date: September 30, 1998
Partner: UNT Libraries Government Documents Department

Enhanced Sulfur Removal of Coal Via Carbon Fiber Production

Description: The characterization of highly graphitic vapor-grown carbon fiber (VGCF) produced by the floating catalyst method was determined to evaluate the effect of processing changes on the VGCF properties. Properties examined were bulk density, bulk resistivity of compressed fiber bundles, UV absorption of acetone extractables, graphitic index, pH value, and ASTM dibutyl phthalate absorption number. The data show the properties do not vary significantly from three different reactor tubes used to produce the fibers. Of the properties examined, only graphitic index, density and UV absorption of acetone extractables appear to be independent of sampling handling. Resistivity is directly correlated to the pressure exerted to from the fiber pellet due to the layering of the fiber bundles. The pH of fiber samples suspended in water does not vary significantly. The dibutyl phthalate absorption number is strongly affected by the compression of the material. Thus, only the graphitic index, the UV absorption of acetone extractables, and the apparent density will be used to aid in process quality control and to determine the process conditions required to produce carbon fiber with properties optimized for specific conditions using high sulfur coal dust.
Date: May 30, 1997
Creator: Patterson, Alesha; Grffith, David; Buffinger, Delbert; Asikele, Edward; Smitherman, Herbert & Evbuoma, Osagie
Partner: UNT Libraries Government Documents Department

Task 2.0 - Air Quality Assessment, Control, and Analytical Methods Subtask 2.11 - Lactic Acid FGD Additives From Sugar Beet Wastewater

Description: Organic buffers maintain the pH of the scrubber slurry in flue gas desulfurization (FGD) as the SO2 dissolves at the air-liquid interface. Inexpensive acids with an appropriate pKa are required for this application. The pKa of lactic acid (3.86) is between that of the interface and the recirculating slurry and will make soluble calcium ion available in large amounts. Currently lactic acid is somewhat expensive for this use, but this project will develop a new source of inexpensive lactate. Microbial action during the storage and processing of sugar beets forms lactic acid in concentrations as high 14 g/L in the processing water. The concentrations are lower than those occurring in conventional fermentation production of lactic acids, but since a considerable amount of water is involved in the processing of sugar beets in the Red River Valley (1 million gallons/day), a substantial amount of lactic acid or calcium lactate could be recovered as a by- product for use in FGD and other applications.
Date: February 1, 1998
Creator: Olson, Edwin S.
Partner: UNT Libraries Government Documents Department

Bench-Scale Demonstration of Hot-Gas Desulfurization Technology

Description: The U.S. Department of Energy (DOE), Federal Energy Technology Center (FETC), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal-derived fuel-gas) streams of integrated gasification combined-cycle (IGCC) power systems. The hot gas cleanup work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs.
Date: December 1, 1998
Creator: Portzer, Jeffrey W. & Gangwal, Santosh K.
Partner: UNT Libraries Government Documents Department

High SO2 Removal Efficiency Testing

Description: This document provides a discussion of the technical progress on DOE/PETC project number DE-AC22-92PC91338, "High Efficiency SO2 Removal Testing", for the time period 1 April through 30 June 1997. The project involves testing at six full-scale utility flue gas desulfurization (FGD) systems to evaluate low capital cost upgrades that may allow these systems to achieve up to 98% SO2 removal efficiency. The upgrades being evaluated mostly involve using performance additives in the FGD systems. The "base" project involved testing at the Tampa Electric Company�s Big Bend Station. All five potential options to the base program have been exercised by DOE, involving testing at Hoosier Energy�s Merom Station (Option I), Southwestern Electric Power Company�s Pirkey Station (Option II), PSI Energy�s Gibson Station (Option III), Duquesne Light�s Elrama Station (Option IV), and New York State Electric and Gas Corporation�s Kintigh Station (Option V). The originally planned testing has been completed for all six sites. However, additional testing is being conducted at the Big Bend Station. The remainder of this document is divided into four sections. Section 2, Project Summary, provides a brief overview of the status of technical efforts on this project. Section 3, Results, summarizes the outcome from technical efforts during the quarter, or results from prior quarters that have not been previously reported. In Section 4, Plans for the Next Reporting Period, an overview is provided of the technical efforts that are anticipated for the third quarter of calendar year 1997. Section 5 contains a brief acknowledgment.
Date: July 29, 1997
Creator: Blythe, Gary
Partner: UNT Libraries Government Documents Department

High SO2 Removal Efficiency Testing

Description: This document provides a discussion of the technical progress on DOE/PETC project number DE-AC22-92PC91338, "High Efficiency SO Removal Testing," for 2 the time period 1 October through 31 December 1996. The project involves testing at six full-scale utility flue gas desulfurization (FGD) systems, to evaluate low capital cost upgrades that may allow these systems to achieve up to 98% SO removal efficiency. The upgrades being 2 evaluated mostly involve using performance additives in the FGD systems. The "base" project involved testing at the Tampa Electric Company�s Big Bend Station. All five potential options to the base program have been exercised by DOE, involving testing at Hoosier Energy�s Merom Station (Option I), Southwestern Electric Power Company�s Pirkey Station (Option II), PSI Energy�s Gibson Station (Option III), Duquesne Light�s Elrama Station (Option IV), and New York State Electric and Gas Corporation�s Kintigh Station (Option V). The originally planned testing has been completed for all six sites. However, additional testing has been planned at the Big Bend Station, and that testing commenced during the current quarter. The remainder of this document is divided into four sections. Section 2, Project Summary, provides a brief overview of the status of technical efforts on this project. Section 3, Results, summarizes the outcome from technical efforts during the quarter, or results from prior quarters that have not been previously reported. In Section 4, Plans for the Next Reporting Period, an overview is provided of the technical efforts that are anticipated for the first quarter of calendar year 1996. Section 5 contains a brief acknowledgment.
Date: February 12, 1997
Creator: Blythe, Gary
Partner: UNT Libraries Government Documents Department

Physical Parameters in Synthoil Process, Quarterly Report: January-March 1976

Description: This work is being done in support of the development of processes for converting coal to liquid fuel of low sulfur content, suitable for use in power production. Most of the effort is intended to produce information applicable to the SYNTHOIL Process. In the SYNTHOIL Process for converting coal to a low-sulfur fuel oil, coal is liquefied and hydro-desulfurized in a turbulent-flow, catalytic packed-bed reactor. A slurry of coal in recycled oil is reacted with hydrogen at 450 degrees C and 2,000 to 4,000 psi in the presence of Co-MoSiO2-Al2O3 catalyst. The turbulent flow of fluid prevents the coal's mineral matter from settling and plugging the reactor. The gross liquid products are centrifuged to remove the unreacted solids. The centrifuged liquid product is a low-S, low-ash fuel. The following four tasks are included: (1) heat of reaction of hydrogen with coal slurries; (2) heat transfer coefficient; (3) additives to facilitate separation of solids from liquids; and (4) catalyst testing. These are now in the planning stage of development.
Date: 1976?
Creator: Fischer, J.; Lo, R.; Nandi, S.; Fredrickson, D.; Bump, T. R.; Mulcahey, T. P. et al.
Partner: UNT Libraries Government Documents Department

ADVANCED SULFUR CONTROL CONCEPTS FOR HOT GAS DESULFURIZATION TECHNOLOGY

Description: The objective of this project is to develop a hot-gas desulfurization process scheme for control of H{sub 2}S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct.
Date: December 31, 1998
Partner: UNT Libraries Government Documents Department

New ZnO-Based Regenerable Sulfur Sorbents for Fluid-Bed/Transport Reactor Applications

Description: The overall objective of the ongoing sorbent development work at GTI is the advancement to the demonstration stage of a promising ZnO-TiO2 sulfur sorbent that has been developed under DCCA/ICCI and DOE/NETL sponsorship. This regenerable sorbent has been shown to possess an exceptional combination of excellent chemical reactivity, high effective capacity for sulfur absorption, high resistance to attrition, and regenerability at temperatures lower than required by typical zinc titanates.
Date: September 19, 2002
Creator: Slimane, R.B.; Lau, F.S.; Abbasian, J. & Ho, K.H.
Partner: UNT Libraries Government Documents Department