Overshadowed by news that FutureGen—the nation’s first commercial-scale coal-fired carbon capture and storage (CCS) project—had regained the Department of Energy’s (DOE’s) backing, the DOE’s financial awards on Friday to nine smaller projects that will develop precombustion carbon capture technologies for future integrated gasification combined cycle (IGCC) power plants went almost unnoticed.

The projects, totaling nearly $14.4 million, will be managed by the DOE’s National Energy Technology Laboratory. Precombustion processes convert fossil fuels into a gaseous mixture of hydrogen and CO2 prior to combustion. The CO2 is then separated and the hydrogen-rich gas can be used in power plants. Compared with postcombustion processes, the pressure and concentration of CO2 in precombustion processes are relatively high—offering the potential to apply novel CO2 capture technologies such as membranes, solvents, and sorbents.

High-Temperature, High-Pressure Membranes

“Membrane” generically refers to a barrier or a medium that selectively separates out a desired gas species, such as hydrogen or CO2, at commercially relevant conditions. According to the DOE, the focus of this research area is membrane-based separation devices approaching the theoretical separation selectivity and flux compatible with throughput rates of today’s gasification technology.

  • University of Minnesota (Minneapolis, Minn.): This project aims to develop defect-free, contaminant-resistant, hydrothermally stable molecular sieve membrane films with minimally tortuous path for diffusion of the preferred hydrogen molecules from the shifted synthesis gas mixtures (DOE share: $793,775; recipient share: $199,997; duration: 48 months).
  • Pall Corp. (Cortland, N.Y.): Pall Corp. will leverage its proprietary combinatorial membrane fabrication technology to screen a large number of potential ternary palladium (Pd) alloys for sulfur-tolerant, phase-stabilized hydrogen transport membrane candidates for separating hydrogen from shifted synthesis gas mixtures (DOE share: $1,207,289; recipient share: $310,000; duration: 36 months).
  • Arizona State University (Tempe, Ariz.): Researchers at Arizona State will integrate the water gas shift reaction with a CO2 selective membrane to separate CO2 from shifted synthesis gas (DOE share: $656,316; recipient share: $164,088; duration: 48 months).

High-Efficiency Solvents

The DOE had sought applications in this research area that could lead to optimal performance of novel, high-efficiency solvents for CO2 absorption, and which would allow a step-change reduction in energy requirements compared to conventional solvents.

  • SRI International (Menlo Park, Calif.): SRI will use aqueous NH4CO3 based solvents to capture high-pressure CO2 at lower solvent cost and with an efficient regeneration process (DOE share: $1,998,455; recipient share: $399,691 [will be increased to $499,613 to meet the 20% requirement]; duration: 24 months).

Solid Sorbents

In this research area, applications were sought for R&D that could lead to optimal performance of novel sorbents for adsorbing CO2 with fast adsorption-desorption, regeneration kinetics, and a low energy requirement to regenerate the sorbent material.

  • TDA Research, Inc. (Wheat Ridge, Colo.): TDA will develop novel mesoporous carbon with Lewis base functionalized groups that remove CO2 via physical adsorption (DOE share: $2,000,000; recipient share: $500,000; duration: 24 months).
  • URS Group (Austin, Texas): Using a molecular computational approach to formulate and then fabricate superior sorbent material, URS Group will combine modeling and experiments to tailor sorbents properties for optimum CO2 capture (DOE share: $1,999,934; recipient share: $684,462; duration: 36 months).

Novel Concepts

The DOE solicited novel ideas on precombustion removal of the carbon content of the fuel and separation devices beyond current benchmarks of performance and cost that can separate hydrogen or CO2 from the water gas shift mixtures. In either option, the hydrogen must be available for the IGCC plant at practical rates and purity.

  • Gas Technology Institute (Des Plaines, Ill.): GTI will couple an engineered plastic contactor with an appropriate solvent to potentially achieve 60% operating cost and 70% capital cost reduction (DOE share: $999,607; recipient share: $273,846; duration: 24 months).
  • Membrane Technology and Research, Inc. (Menlo Park, Calif.): Membrane Technology and Research will develop a novel polymer membrane(s) for the separation of hydrogen from shifted synthesis gas (DOE share: $952,764; recipient share: $240,061; duration: 24 months).
  • New Jersey Institute of Technology (Newark, N.J.): Researchers propose a pressure swing absorption approach to capture CO2 using an ionic liquid incorporated in either a ceramic hollow tube or polytetrafluoroethylene (PTFE) fiber membrane (DOE share: $805,819; recipient share: $206,017; duration: 36 months).

Source: DOE