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Title: Energy and environmental research emphasizing low-rank coal -- Task 3.10, Gas separation and hot-gas cleanup

Abstract

Catalytic gasification of coal to produce H{sub 2}-, CO-, and CH{sub 4}-rich mixtures of gases for consumption in molten carbonate fuel cells is currently under development; however, to optimize the fuel cell performance and extend its operating life, it is desired to separate as much of the inert components (i.e., CO{sub 2} and N{sub 2}) and impurities (i.e., H{sub 2}S and NH{sub 3}) as possible from the fuel gas before it enters the fuel cell. In addition, the economics of the integrated gasification combined cycle (IGCC) can be improved by separating as much of the hydrogen as possible from the fuel, since hydrogen is a high-value product. Researchers at the Energy and Environmental Research Center (EERC) and Bend Research, Inc., investigated pressure-driven membranes as a method for accomplishing this gas separation and hot-gas cleanup. These membranes are operated at temperatures as high as 800 C and at pressures up to 300 psig. They have very small pore sizes that separate the undesirable gases by operating in the Knudsen diffusion region of mass transport or in the molecular sieving region of mass transport phenomena. In addition, H{sub 2} separation through a palladium metal membrane proceeds via a solution-diffusion mechanism for atomicmore » hydrogen. This allows the membranes to exhibit extremely high selectivity for hydrogen separation. Specific questions to be answered in this project include: what are the effects of membrane properties (i.e., surface area, pore size, and coating thickness) on permeability and selectivity of the desired gases; what are the effects of operating conditions (i.e., temperature, pressure, and flow rate) on permeability and selectivity; what are the effects of impurities (i.e., small particulate, H{sub 2}S, HCl, NH{sub 3}, etc.) on membrane performance?« less

Authors:
Publication Date:
Research Org.:
North Dakota Univ., Grand Forks, ND (United States). Energy and Environmental Research Center
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
206507
Report Number(s):
DOE/MC/30097-5086
ON: DE96000618; TRN: AHC29607%%24
DOE Contract Number:
FC21-93MC30097
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Aug 1995
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; FUEL GAS; HOT GAS CLEANUP; MEMBRANES; PERFORMANCE TESTING; PHYSICAL PROPERTIES; PARAMETRIC ANALYSIS; HYDROGEN SULFIDES; HYDROCHLORIC ACID; AMMONIA; FLY ASH; CARBON DIOXIDE; NITROGEN; COAL GASIFICATION; MEMBRANE TRANSPORT; TEST FACILITIES; SUBBITUMINOUS COAL; PALLADIUM; SILVER; EXPERIMENTAL DATA; HYDROGEN

Citation Formats

Swanson, M.L. Energy and environmental research emphasizing low-rank coal -- Task 3.10, Gas separation and hot-gas cleanup. United States: N. p., 1995. Web. doi:10.2172/206507.
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Swanson, M.L. Energy and environmental research emphasizing low-rank coal -- Task 3.10, Gas separation and hot-gas cleanup. United States. doi:10.2172/206507.
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Swanson, M.L. Tue . "Energy and environmental research emphasizing low-rank coal -- Task 3.10, Gas separation and hot-gas cleanup". United States. doi:10.2172/206507. https://www.osti.gov/servlets/purl/206507.
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@article{osti_206507,
title = {Energy and environmental research emphasizing low-rank coal -- Task 3.10, Gas separation and hot-gas cleanup},
author = {Swanson, M.L.},
abstractNote = {Catalytic gasification of coal to produce H{sub 2}-, CO-, and CH{sub 4}-rich mixtures of gases for consumption in molten carbonate fuel cells is currently under development; however, to optimize the fuel cell performance and extend its operating life, it is desired to separate as much of the inert components (i.e., CO{sub 2} and N{sub 2}) and impurities (i.e., H{sub 2}S and NH{sub 3}) as possible from the fuel gas before it enters the fuel cell. In addition, the economics of the integrated gasification combined cycle (IGCC) can be improved by separating as much of the hydrogen as possible from the fuel, since hydrogen is a high-value product. Researchers at the Energy and Environmental Research Center (EERC) and Bend Research, Inc., investigated pressure-driven membranes as a method for accomplishing this gas separation and hot-gas cleanup. These membranes are operated at temperatures as high as 800 C and at pressures up to 300 psig. They have very small pore sizes that separate the undesirable gases by operating in the Knudsen diffusion region of mass transport or in the molecular sieving region of mass transport phenomena. In addition, H{sub 2} separation through a palladium metal membrane proceeds via a solution-diffusion mechanism for atomic hydrogen. This allows the membranes to exhibit extremely high selectivity for hydrogen separation. Specific questions to be answered in this project include: what are the effects of membrane properties (i.e., surface area, pore size, and coating thickness) on permeability and selectivity of the desired gases; what are the effects of operating conditions (i.e., temperature, pressure, and flow rate) on permeability and selectivity; what are the effects of impurities (i.e., small particulate, H{sub 2}S, HCl, NH{sub 3}, etc.) on membrane performance?},
doi = {10.2172/206507},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Aug 01 00:00:00 EDT 1995},
month = {Tue Aug 01 00:00:00 EDT 1995}
}
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Technical Report:
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DOI:  10.2172/206507
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