Search NASA⌕ Search

SEARCH · Search NASA

Results for “condensing boilers”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

103 records · Page 6

Advanced Membrane Separation Technologies for Energy Recovery from Industrial Process Streams

Recovery of energy from relatively low-temperature waste streams is a goal that has not been achieved on any large scale. Heat exchangers do not operate efficiently with low-temperature streams and thus require such large heat exchanger surface areas that they are not practical. Condensing economizers offer one option for heat recovery from such streams, but they have not been widely implemented by industry. A promising alternative to these heat exchangers and economizers is a prototype ceramic membrane system using transport membrane technology for separation of water vapor and recovery of heat. This system was successfully tested by the Gas Technology Institute (GTI) on a natural gas fired boiler where the flue gas is relatively clean and free of contaminants. However, since the tubes of the prototype system were constructed of aluminum oxide, the brittle nature of the tubes limited the robustness of the system and even limited the length of tubes that could be used. In order to improve the robustness of the membrane tubes and make the system more suitable for industrial applications, this project was initiated with the objective of developing a system with materials that would permit the system to function successfully on a larger scale and in contaminated and potentially corrosive industrial environments. This required identifying likely industrial environments and the hazards associated with those environments. Based on the hazardous components in these environments, candidate metallic materials were identified that are expected to have sufficient strength, thermal conductivity and corrosion resistance to permit production of longer tubes that could function in the industrial environments identified. Tests were conducted to determine the corrosion resistance of these candidate alloys, and the feasibility of forming these materials into porous substrates was assessed. Once the most promising metallic materials were identified, the ability to form an alumina membrane layer on the surface of the metallic tubes was evaluated. Evaluation of this new style of membrane tube involved exposure to SO 2 containing gases as well as to materials with a potential for fouling. Once the choice of substrate and membrane materials and design were confirmed, about 150 tubes were fabricated and assembled into three modules. These modules were mounted on an industrial size boiler and their performance carefully monitored during a limited testing period. The positive results of this performance test confirm the feasibility of utilizing such a system for recovery of heat and water from industrial waste streams. The improved module design along with use of long metallic substrate tubes with a ceramic membrane on the outer surface resulted in the successful, limited scale demonstration of the Transport Membrane Condenser (TMC) technology in the GTI test facility. This test showed this technology can successfully recover a significant amount of heat and water from gaseous waste streams. However, before industry will make the investment to install a full scale TMC, a full scale system will need to be constructed, installed and successfully operated at a few industrial sites. Companies were identified that had an interest in serving as a host site for a demonstration system.

Keiser, James R.↗

Design of a pool boiler heat transport system for a 25 kWe advanced Stirling conversion system

The overall operating temperature and efficiency of solar-powered Stirling engines can be improved by adding a heat transport system to more uniformly supply heat to the heater head tubes. One heat transport system with favorable characteristics is an alkali metal pool boiler. An alkali metal pool boiler heat transport system was designed for a 25-kW advanced Stirling conversion system (ASCS). Solar energy concentrated on the absorber dome boils a eutectic mixture of sodium and potassium. The alkali metal vapors condense on the heater head tubes, supplying the Stirling engine with a uniform heat flux at a constant temperature. Boiling stability is achieved with the use of an enhanced boiling surface and noncondensible gas.

Anderson, W. G.↗

Simultaneous Waste Heat and Water Recovery from Power Plant Flue Gases for Advanced Energy Systems

This final report presents the results of a two-year technology development project carried out by a team of participants sponsored by the Department of Energy (DOE). The objective of this project is to develop a membrane-based technology to recover both water and low grade heat from power plant flue gases. Part of the recovered high-purity water and energy can be used directly to replace plant boiler makeup water as well as improving its efficiency, and the remaining part of the recovered water can be used for Flue Gas Desulfurization (FGD), cooling tower water makeup or other plant uses. This advanced version Transport Membrane Condenser (TMC) with lower capital and operating costs can be applied to existing plants economically and can maximize waste heat and water recovery from future Advanced Energy System flue gases with CO 2 capture in consideration, which will have higher moisture content that favors the TMC to achieve higher efficiency.

20 FOSSIL-FUELED POWER PLANTS↗

Absorption of solar radiation by alkali vapors

A theoretical study of the direct absorption of solar radiation by the working fluid of high temperature, high efficiency energy converters has been carried out. Alkali vapors and potassium vapor in particular were found to be very effective solar absorbers and suitable thermodynamically for practical high temperature cycles. Energy loss via reradiation from a solar boiler was shown to reduce the overall efficiency of radiation-heated energy converters, although a simple model of radiation transfer in a potassium vapor solar boiler revealed that self-trapping of the reradiation may reduce this loss considerably. A study was also made of the requirements for a radiation boiler window. It was found that for sapphire, one of the best solar transmitting materials, the severe environment in conjunction with high radiation densities will require some form of window protection. An aerodynamic shield is particularly advantageous in this capacity, separating the window from the absorbing vapor to prevent condensation and window corrosion and to reduce the radiation density at the window.

Mattick, A. T.↗

Acceptance criteria for welds in ASTM A106 grade B steel pipe and plate

Based on the RECERT Program findings, NASA-Langley funded a fatigue study of code-unacceptable welds. Usage curves were developed which were based on the structural integrity of the welds. The details of this study are presented in NASA CR-178114. The information presented is a condensation and reinterpretation of the information in NASA CR-178114. This condensation and reinterpretation generated usage curves for welds having: (1) indications 0.20 -inch deep by 0.40-inch long, and (2) indications 0.195-inch deep by 8.4-inches long. These curves were developed using the procedures used in formulating the design curves in Section VIII, Division 2 of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code.

Hudson, C. M.↗

Advanced Membrane Separation Technologies for Energy Recovery from Industrial Process Streams

Recovery of energy from relatively low-temperature waste streams is a goal that has not been achieved on any large scale. Heat exchangers do not operate efficiently with low-temperature streams and thus require such large heat exchanger surface areas that they are not practical. Condensing economizers offer one option for heat recovery from such streams, but they have not been widely implemented by industry. A promising alternative to these heat exchangers and economizers is a prototype ceramic membrane system using transport membrane technology for separation of water vapor and recovery of heat. This system was successfully tested by the Gas Technology Institute (GTI) on a natural gas fired boiler where the flue gas is relatively clean and free of contaminants. However, since the tubes of the prototype system were constructed of aluminum oxide, the brittle nature of the tubes limited the robustness of the system and even limited the length of tubes that could be used.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

AFUE Analysis Software Tool

The Annual Fuel Utilization Efficiency (AFUE) analysis of residential and light commercial furnaces follows ANSI/ASHRAE Standard 103-2017 (i.e., Method of Testing for Annual Fuel Utilization Efficiency of Residential Central Furnaces and Boilers) . The analysis is a complex, comprehensive method based on furnace configuration and specific components equipped, requiring detailed furnace testing and measurement data. For this reason, an AFUE Analysis Tool using Microsoft Excel enabled with Visual Basic for Applications (VBA) was developed with a user-friendly interface and comprehensive coverage. The tool consists of three worksheets: unit and configuration selection, geometry and measurement data input, and AFUE plus key results. This tool can be used to estimate the AFUE of both condensing and noncondensing furnaces with single-stage, two-stage, and step-modulating functions. The tool was validated with experimental data from Oak Ridge National Laboratory’s natural gas furnace projects that are commercially available. The results indicate the tool is reasonably accurate in the evaluation of a new R&D modified furnace unit.

Gao, Zhiming [Oak Ridge National Laboratory (ORNL)↗

Use Steam Jet Ejectors or Thermoscompressors to Reduce Venting of Low-Pressure Steam - Steam Tip Sheet #29 (Fact Sheet)

This revised AMO tip sheet on steam jet ejectors and thermocompressors provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies. Large industrial plants often vent significant quantities of low-pressure steam to the atmosphere, wasting energy, water, and water-treatment chemicals. Recovery of the latent heat content of low-pressure steam reduces the boiler load, resulting in energy and fuel cost savings. Low-pressure steam’s potential uses include driving evaporation and distillation processes, producing hot water, space heating, producing a vacuum, or chilling water. If the steam pressure is too low for the intended application, a steam jet thermocompressor can boost the pressure and temperature to the required level.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Clean Condensing Gas Furnace

Natural gas furnaces are the most common space heating equipment in the U.S. residential and commercial building markets. However, current residential natural gas condensing furnaces generate substantial acidic condensate as well as significant emissions of sulfur oxides (SOx), nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HC), and methane (CH 4 ) contributing to environmental degradation of air, water, and soil. This report describes a novel solution to reduce the environmental impact of natural gas condensing furnaces based on the technology of a monolithic acidic gas reduction (AGR) catalyst for SOx trapping, NOx redox to nitrogen, and oxidation of formic acid, CO, HC, and CH 4 . The AGR technology offers the following benefits: (1) a neutral furnace condensate with a pH of ~7, allowing its safe release into the sewer system thus eliminating a second drainage system; (2) trapping and removing nearly all SOx emissions; (3) NOx emissions nearly at nearly 1-2 ng/J, more than 95% lower than new emissions standards in California; (4) the use of a low-cost heat exchanger as a condensing heat exchanger (HX) since the condensate is not acidic, avoiding the need for expensive stainless steel alloys; and (5) unburnt fuel energy recovery to boost efficiency.The AGR component and AGR-enabled furnace performance were broadly tested to determine their effects on long-term reliability and durability, as well as SOx storage and regeneration activity. The AGR regeneration does not impair the performance in achieving neutral condensate and ultra-low NOx emissions, and the AGR catalyst subjected to regeneration activities continued to function well and achieved slightly better annual fuel utilization efficiency (AFUE). The 400-hour reliability and durability test of the retrofitted condensing furnace with the AGR component shows that the furnace unit still achieves a neutral furnace condensate with a pH of ~7 and enables 0~3 ng/J of NOx emissions. However, the 400-hour operation slightly degraded the AFUE because of soot particle accumulation caused by frequent incomplete combustion owing to inappropriate condensate drainage during testing. Thus, proper condensate drainage is critical for AGR-enabled furnaces. Furthermore, neutron computed tomography was employed to survey the aged AGR component and demonstrate high-resolution 2D and 3D representations for the nondestructive diagnosis of the AGR component. The tomography showed that the AGR component did not deform or suffer broken AGR channels. A new AGR catalyst with low precious metal loading was preliminarily explored to identify a pathway of optimizing AGR material loading and maximizing acidic gas reduction at low cost. The new AGR component can reduce precious metal loading by 38% and still achieve neutral condensate and ultralow NOx emissions. The furnace with the AGR component of low Pt/Rh loading enables a maximum AFUE of 97%, which is meaningfully higher than the original furnace. Long-duration testing for the furnace enabled with the low precious metal loading AGR component will be vital in future research. Although the current work demonstrates a proof of concept for the AGR-enabled furnace, the AGR assembly needs to be optimized and integrated into the design of new OEM furnace products. Furthermore, the AGR technology can be applied not only for residential gas furnaces, but also for commercial rooftop units, gas heat pumps, gas-fired water heaters, combustion boilers, and other systems.

03 NATURAL GAS↗

Improving Gas Furnace Performance: A Field and Laboratory Study at End of Life

In 2010, natural gas provided 54% of total residential space heating energy the U.S. on a source basis, or 3.5 Quadrillion Btu. Natural gas burned in furnaces accounted for 92% of that total, and boilers and other equipment made up the remainder. A better understanding of installed furnace performance is a key to energy savings for this significant energy usage. Natural gas furnace performance can be measured in many ways. The annual fuel utilization efficiency (AFUE) rating provides a fixed value under specified conditions, akin to the EPA miles per gallon rating for new vehicles. The AFUE rating is provided by the manufacturer to the consumer and is a way to choose between models tested on the same basis. This value is commonly used in energy modeling calculations. ASHRAE 103 is a consensus furnace testing standard developed by the engineering community. The procedure provided in the standard covers heat-up, cool down, condensate heat loss, and steady-state conditions and an imposed oversize factor. The procedure can be used to evaluate furnace performance with specified conditions or with some variation chosen by the tester. In this report the ASHRAE 103 test result will be referred to as Annualized Efficiency (AE) to avoid confusion, and any non-standard test conditions will be noted. Aside from these two laboratory tests, steady state or flue loss efficiency can be measured in the field under many conditions; typically as found or tuned to the manufacturers recommended settings. In this report, AE and steady-state efficiency will be used as measures of furnace performance.

03 NATURAL GAS↗

Characterization of Dried and Torrefied Arundo Donax Biomass for Inorganic Species Prior to Combustion

Portland General Electric (PGE) potentially plans to replace the coal with torrefied Arundo donax for their Boardman coal-fired power plant by 2020. Since there is only a limited amount of experience with this high yield energy crop, PGE would like to characterize raw and torrefied Arundo before a test burn and therefore avoid possible ash related operational problems such as slagging, deposit formation and corrosion. This report describes the results from characterization of ground and cross-sectioned samples of Arundo with a high-resolution scanning electron microscopy and energy dispersive spectroscopy, and also includes analytical results from a short water-leaching test for concentrations of Ca, Mg, K, Na, S, and Cl in the non-leached and leached Arundo and leachates. SEM-EDS analysis of torrefied Arundo revealed that condensation of volatile components during torrefaction can result in their undesirable re-deposition on the outside surfaces in the form of amorphous or crystallized clusters with a size from a few µm’s to as large as 100 µm. A short exposure of Arundo to water resulted in an efficient removal of volatile species from the raw and torrefied Arundo, e.g., ~ 98 wt% of total K and Cl, and ~75 wt% of total S were removed from raw Arundo, and more than 90 wt% of total K and Cl, and 70 wt% of S from torrefied Arundo, suggesting that water-leaching of Arundo before combustion can be an effective pre-treatment method because high concentrations of Cl increase emissions of HCl, and in combination with K can form large amounts of KCl deposits on boiler surfaces and in combination with H 2 O or SO 3 cause corrosion.

Arundo↗

An Integrated Supercritical System for Efficient Produced Water Treatment and Power Generation

The main goal of this project was to evaluate the feasibility of an integrated supercritical (SC) water desalination and power generation system for treatment of produced waters from CO 2 sequestration, oil production, and coal-bed methane recovery. This system may offer a transformative approach to generating power from coal or natural gas (NG) and purifying saline water or produced water with high total dissolved solids (TDS) in a zero-liquid discharge plant. The closed-loop steam cycle of conventional power plants was replaced with an open-loop steam cycle that heated the pretreated produced water above the SC point of water (374 °C and 221 bar) to precipitate and separate the salts dissolved in the water. After separation of the precipitated salt, the SC steam required further treatment to reduce the salt content from ~100 mg/L (ppm) to <1 ppm to make it suitable for use in turbines for power generation. A SC membrane distillation unit was used to polish the SC steam, which could be sent through a series of turbines for power generation, and the steam exiting the low-pressure turbine could be condensed by cooling water to produce pure water. Project tasks included a process simulation and a techno-economic evaluation of the integrated system; design and assembly of SC salt precipitation and membrane distillation systems; development and characterization of advanced carbon membranes for SC membrane distillation; and pretreatment, desalination, and purification of different produced water samples with salt concentrations of 30,000–200,000 ppm to a high-purity (<1 ppm) level. Process simulations were performed for 550 MW SC coal-fired or NG baseline cases and various scenarios for the proposed integrated SC system using produced water as the water source and coal or NG as the fuel source. Simulation results indicated that the net plant efficiency loss of the proposed SC cogeneration process would be in the range of <1% to ~4%, in which NG and lower TDS produced water cases would have higher efficiencies. The proposed process for coal-fired cases could provide all water needs for the power generation process and generate additional pure water for beneficial use. A techno-economic analysis was performed to estimate the cost of produced water treatment (dollars /kgal of treated water) by conventional treatment processes compared with the proposed cogeneration process. The cost estimation for the proposed cogeneration system included the cost of pretreatment, the cost of power loss to integrate the water desalination process into the power generation system, and the cost of plant modification or retrofitting. The cost of produced water treatment was calculated by assuming three different scenarios in which converting a baseline power plant to the proposed cogeneration plant would increase the cost of the boiler and feed water system by 10%, 50%, and 100%. Results indicated that the cost of produced water treatment, even with a 100% cost increase, was in the range of $8.6–11.6 dollars per kgal, which is about half of the treatment cost by conventional methods. The cost of produced water treatment by the proposed cogeneration system could be further reduced or a considerable income could be generated if the values of saltwater and freshwater products are considered. Overall, the techno-economic analysis results indicated that the proposed integrated SC system could potentially treat produced water at a cost significantly lower than the cost of produced water treatment by conventional technologies. To evaluate the feasibility of the proposed treatment system at a laboratory scale, a SC salt precipitation and membrane distillation system was designed and fabricated to treat a simulated brine or pretreated produced water by precipitating salts and further polishing the SC steam containing ~100 ppm salts to a high-purity steam. Through baseline tests with NaCl solutions, with concentrations ranging from 30,000 to 200,000 ppm, it was demonstrated that concentrated feed solutions could be treated by precipitating salt at SC conditions to a TDS level of 130 ppm. Produced water samples were collected from a potential CO 2 sequestration site, a coal-bed methane site, and an oilfield in Illinois. Representative samples were characterized for various water quality parameters, including pH; turbidity; conductivity; and concentrations of selected anions, cations, alkalinity, dissolved organic carbon, total suspended solids, TDS, and total petroleum hydrocarbons. The produced water samples were first treated by conventional pretreatment methods to remove residual oil, dissolved organic matter, and scale-forming species. Pretreatment methods included coagulation, sedimentation, filtration, activated carbon adsorption, and ion-exchange adsorption. Pretreated produced waters were treated at SC conditions in which salts were precipitated. Analysis of treated samples revealed that the concentration of Na (the main cation) in produced waters was reduced dramatically from 14,000–47,400 ppm in the feed to 21–80 ppm in treated waters. Concentrations of other main cations (Ca, Mg, Sr, K) also decreased significantly from initial values of ~1,000–22,000 ppm to ~1 ppm or less. However, a significant increase in the concentrations of Fe, Ni, Cu, and Co was observed, mainly caused by leaching of these elements from the system (vessels, filters, tubing), which is manufactured from alloys containing Fe, Ni, Cu, and Co. To polish the SC steam containing a salt content of ~100 ppm to a high-purity level of <1 ppm, a SC membrane distillation treatment using carbon membranes was employed. Different types of self-standing or supported carbon membranes were developed from graphite, graphene, carbon nanotubes, carbon nanofibers, and pyrolytic carbon. Screening tests revealed that only a limited number of developed carbon membranes were suitable for the purification of steam at SC conditions. Membranes that were either fragile and lacked mechanical strength or had large pores and showed limited salt rejection (<20%) were found to be unsuitable for the purification of SC steam. Promising carbon membranes that were successfully tested for purifying SC steam included two graphite membranes (i.e., AF-5, a porous graphite material, and FGS, a flexible graphite sheet) and a carbon nanotube membrane grown on a Hastelloy substrate and then further modified using a proprietary method (i.e., membrane C). The AF-5 membrane exhibited a stable water flux of ~50 kg/m 2 ∙h and ~40% salt rejection. The FGS membrane had a high salt rejection of 95%–98% but a lower water flux of ~15 kg/m 2 ∙h. Membrane C showed an extremely high flux of 200-800 kg/m 2 ∙h, which is one order of magnitude higher than the water flux of conventional membranes. Membrane C also exhibited 87%–93% salt rejection. Overall, a two-stage or multistage polishing treatment by these membranes could lower the salt content of the SC steam from initial values of ~100–200 ppm to the steam quality of <1 ppm or to parts per billion levels required for the power cycle.

20 FOSSIL-FUELED POWER PLANTS↗

Evaluation of Dry Sorbent Injection Technology for Pre-Combustion CO{sub 2} Capture

This document summarizes the work performed on Cooperative Agreement DE-FE0000465, “Evaluation of Dry Sorbent Technology for Pre-Combustion CO{sub 2} Capture,” during the period of performance of January 1, 2010 through September 30, 2013. This project involves the development of a novel technology that combines a dry sorbent-based carbon capture process with the water-gas-shift reaction for separating CO{sub 2} from syngas. The project objectives were to model, develop, synthesize and screen sorbents for CO{sub 2} capture from gasified coal streams. The project was funded by the DOE National Energy Technology Laboratory with URS as the prime contractor. Illinois Clean Coal Institute and The University of Illinois Urbana-Champaign were project co-funders. The objectives of this project were to identify and evaluate sorbent materials and concepts that were suitable for capturing carbon dioxide (CO{sub 2}) from warm/hot water-gas-shift (WGS) systems under conditions that minimize energy penalties and provide continuous gas flow to advanced synthesis gas combustion and processing systems. Objectives included identifying and evaluating sorbents that efficiently capture CO{sub 2} from a gas stream containing CO{sub 2}, carbon monoxide (CO), and hydrogen (H{sub 2}) at temperatures as high as 650 °C and pressures of 400-600 psi. After capturing the CO{sub 2}, the sorbents would ideally be regenerated using steam, or other condensable purge vapors. Results from the adsorption and regeneration testing were used to determine an optimal design scheme for a sorbent enhanced water gas shift (SEWGS) process and evaluate the technical and economic viability of the dry sorbent approach for CO{sub 2} capture. Project work included computational modeling, which was performed to identify key sorbent properties for the SEWGS process. Thermodynamic modeling was used to identify optimal physical properties for sorbents and helped down-select from the universe of possible sorbent materials to seven that were deemed thermodynamically viable for the process. Molecular modeling was used to guide sorbent synthesis through first principles simulations of adsorption and regeneration. Molecular dynamics simulations also modeled the impact of gas phase impurities common in gasified coal streams (e.g., H{sub 2}S) on the adsorption process. The role of inert dopants added for mechanical durability to active sorbent materials was also investigated through molecular simulations. Process simulations were conducted throughout the project to help determine the overall feasibility of the process and to help guide laboratory operating conditions. A large component of the program was the development of sorbent synthesis methods. Three different approaches were used: mechanical alloying (MA), flame spray pyrolysis (FSP), and ultrasonic spray pyrolysis (USP). Sorbents were characterized by a host of analytical techniques and screened for SEWGS performance using a thermogravimetric analyzer (TGA). A feedback loop from screening efforts to sorbent synthesis was established and used throughout the project lifetime. High temperature, high pressure reactor (HTPR) systems were constructed to test the sorbents at conditions mimicking the SEWGS process as identified through process modeling. These experiments were conducted at the laboratory scale to examine sorbents for their CO{sub 2} capacity, conversion of CO to CO{sub 2}, and impacts of adsorption and regeneration conditions, and syngas composition (including impurities and H2O:CO ratio). Results from the HTPR testing showed sorbents with as high as 0.4 g{sub CO{sub 2}}/g{sub sorbent} capacity with the ability to initially shift the WGS completely towards CO{sub 2}/H{sub 2}. A longer term experiment with a simple syngas matrix and N{sub 2}/steam regeneration stream showed a USP sorbent to be stable through 50 adsorption-regeneration cycles, though the sorbent tested had a somewhat diminished initial capacity. The program culminated in a technoeconomic assessment in which two different approaches were taken; one approach was intended to be technically conservative while the second required several key engineering challenges to be met in order to succeed. The project team is confident that, with the proper support, those challenges could be met. The second approach relies on a slipstream of H{sub 2} from the shifted syngas and O{sub 2} from an air separation unit (ASU) to be combusted in the presence of the sorbent for regeneration; termed a regenerating boiler. The approach also makes use of the heat of adsorption to generate >400 MW of turbine quality steam; total plant gross energy output as high as 1 GW was estimated for an IGCC with an initial gross energy output of 737 MW, without any additional coal usage. The regenerating boiler concept could benefit further from additional heat integration, but the results of this effort show a COE of $97.50 per MWh for a rational combination of operating parameters and sorbent lifetime as well as conservative estimates for steam turbines, gas turbine, and ASU. If the COE of CO{sub 2} transmission, storage and monitoring ($5.60 / MWh) is added to the base case for an IGCC ($81.30 / MWh for Case 5 from the DOE Bituminous Coal Report), the cost of CO{sub 2} capture for the regenerating boiler was only $10.60 / MWh; other regenerating boiler cases are as low $6.90 / MWh. The project met all agreed upon milestones and was completed within budget, more than 25% cost share provided by the project team. Results from the program showed that the SEWGS process has great promise, and with further study and evaluation could become a component of a comprehensive carbon capture program. SEWGS requires a paradigm shift in the traditional approach to carbon capture because the regenerating boiler concept is not a ‘back-end’ solution to CO{sub 2} mitigation. Rather, it is an integral part of the plant operations and is responsible for generating more electricity than the IGCC itself. Schemes could be envisioned where the H{sub 2} production is used exclusively to regenerate the sorbent, with any excess sold as a commodity, and the heat of adsorption serving as the primary driver for power generation. Further work with sorbent evaluation, process modeling and heat integration, and scale-up would be needed to more fully vet SEWGS, but the culmination of this program indicates that additional study is warranted.

20 FOSSIL-FUELED POWER PLANTS↗