Design, Modeling and Simulation of Post Combustion CO2 Capture Systems Using Reactive Solvents

Decarbonization of energy-intensive systems (e.g., heat and power generation, iron, and steel production, petrochemical processes, cement production, etc.) is an important task for the development of a low carbon economy. In this respect, carbon capture technologies will play an important role in the decarbonization of fossil-based industrial processes. The most significant techno-economic and environmental performance indicators of various fossil-based industrial applications decarbonized by two reactive gas-liquid (chemical scrubbing) and gas-solid CO2 capture systems are calculated, compared, and discussed in the present work. As decarbonization technologies, the gas-liquid chemical absorption and more innovative calcium looping systems were employed. The integrated assessment uses various elements, e.g., conceptual design of decarbonized plants, computer-aided tools for process design and integration, evaluation of main plant performance indexes based on industrial and simulation results, etc. The overall decarbonization rate for various assessed applications (e.g., power generation, steel, and cement production, chemicals) was set to 90% in line with the current state of the art in the field. Similar non-carbon capture plants are also assessed to quantify the various penalties imposed by decarbonization (e.g., increasing energy consumption, reducing efficiency, economic impact, etc.). The integrated evaluations exhibit that the integration of decarbonization technologies (especially chemical looping systems) into key energy-intensive industrial processes have significant advantages for cutting the carbon footprint (60–90% specific CO2 emission reduction), improving the energy conversion yields and reducing CO2 capture penalties.

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Comparative performance assessment of USC and IGCC power plants integrated with CO2 capture systems

Fuel ◽

10.1016/j.fuel.2013.06.005 ◽

2014 ◽

Vol 116 ◽

pp. 820-833 ◽

Cited By ~ 40

Author(s):

Giorgio Cau ◽

Vittorio Tola ◽

Paolo Deiana

Keyword(s):

Performance Assessment ◽

Co2 Capture ◽

Power Plants ◽

Comparative Performance ◽

Co2 Capture Systems

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Modeling and simulation of membrane-absorption hybrid systems for CO2 capture from natural gas

Greenhouse Gas Control Technologies 7 ◽

10.1016/b978-008044704-9/50365-7 ◽

2005 ◽

pp. 2519-2523

Author(s):

M SOLTANIEH ◽

A SAEADI

Keyword(s):

Natural Gas ◽

Modeling And Simulation ◽

Hybrid Systems ◽

Co2 Capture ◽

Membrane Absorption

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The Effect of Fossil Fuel Prices on Flexible CO2 Capture Operation

ASME 2009 3rd International Conference on Energy Sustainability, Volume 1 ◽

10.1115/es2009-90308 ◽

2009 ◽

Cited By ~ 3

Author(s):

Stuart M. Cohen ◽

John Fyffe ◽

Gary T. Rochelle ◽

Michael E. Webber

Keyword(s):

Power Plant ◽

Co2 Capture ◽

Electricity Market ◽

Power Plants ◽

Fossil Fuel ◽

Operating Costs ◽

Costs And Benefits ◽

Fuel Prices ◽

Economic Analyses ◽

Co2 Capture Systems

Coal consumption for electricity generation produces over 30% of U.S. carbon dioxide (CO2) emissions, but coal is also an available, secure, and low cost fuel that is currently utilized to meet roughly half of America’s electricity demand. While the world transitions from the existing fossil fuel-based energy infrastructure to a sustainable energy system, carbon dioxide capture and sequestration (CCS) will be a critical technology that will allow continued use of coal in an environmentally acceptable manner. Techno-economic analyses are useful in understanding the costs and benefits of CCS. However, typical techno-economic analyses of post-combustion CO2 capture systems assume continuous operation at a high CO2 removal, which could use 30% of pre-capture electricity output and require new capacity installation to replace the output lost to CO2 capture energy requirements. This study, however, considers the inherent flexibility in post-combustion CO2 capture systems by modeling power plants that vary CO2 capture energy requirements in order to increase electricity output when economical under electricity market conditions. A first-order model of electricity dispatch and a competitive electricity market is used to investigate flexible CO2 capture in response to hourly electricity demand variations. The Electric Reliability Council of Texas (ERCOT) electric grid is used as a case study to compare plant and grid performance, economics, and CO2 emissions in scenarios without CO2 capture to those with flexible or inflexible CO2 capture systems. Flexible CO2 capture systems can choose how much CO2 to capture based on the competition between CO2 and electricity prices and a desire to either minimize operating costs or maximize operating profits. Coal and natural gas prices have varying degrees of predictability and volatility, and the relative prices of these fuels have a major impact on power plant operating costs and the resulting plant dispatch sequence. Because the chosen operating point in a flexible CO2 capture system affects net power plant efficiency, fuel prices also influence which CO2 capture operating point may be the most economical and the resulting dispatch of power plants with CO2 capture. Several coal and natural gas price combinations are investigated to determine their impact on flexible CO2 capture operation and the resulting economic and environmental impacts at the power plant and electric grid levels. This study investigates the costs and benefits of flexible CO2 capture in a framework of a carbon-constrained future where the effects of major energy infrastructure changes on fuel prices are not entirely clear.

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Comparing Flexible CO2 Capture in Gas- and Coal-Dominated Electricity Markets

ASME 2011 5th International Conference on Energy Sustainability, Parts A, B, and C ◽

10.1115/es2011-54359 ◽

2011 ◽

Author(s):

John R. Fyffe ◽

Stuart M. Cohen ◽

Michael E. Webber

Keyword(s):

Natural Gas ◽

Co2 Emissions ◽

Co2 Capture ◽

Electricity Markets ◽

Power Plants ◽

Electricity Price ◽

Economic Viability ◽

Electricity Prices ◽

Modeling Framework ◽

Co2 Capture Systems

Coal-fired power plants are a source of inexpensive, reliable electricity for many countries. Unfortunately, their high carbon dioxide (CO2) emissions rates contribute significantly to global climate change. With the likelihood of future policies limiting CO2 emissions, CO2 capture and sequestration (CCS) could allow for the continued use of coal while low- and zero-emission generation sources are developed and implemented. This work compares the potential impact of flexibly operating CO2 capture systems on the economic viability of using CCS in gas- and coal-dominated electricity markets. The comparison is made using a previously developed modeling framework to analyze two different markets: 1) a natural-gas dominated market (the Electric Reliability Council of Texas, or ERCOT) and 2) a coal-dominated market (the National Electricity Market, or NEM in Australia). The model uses performance and economic parameters for each power plant to determine the annual generation, CO2 emissions, and operating profits for each plant for specified input fuel prices and CO2 emissions costs. Previous studies of ERCOT found that flexible CO2 capture operation could improve the economic viability of coal-fired power plants with CO2 capture when there are opportunities to reduce CO2 capture load and increase electrical output when electricity prices are high. The model was used to compare the implications of using CO2 capture systems in the two electricity systems under CO2 emissions penalties from 0–100 US dollars per metric ton of CO2. Half the coal-fired power plants in each grid were selected to be considered for a CO2 capture retrofit based on plant efficiency, whether or not SO2 scrubbers are already installed on the plant, and the plant’s proximity to viable sequestration sites. Plants considered for CO2 capture systems are compared with and without inflexible CO2 capture as well as with two different flexible operation strategies. With more coal-fired power plants being dispatched as the marginal generator and setting the electricity price in the NEM, electricity prices increase faster due to CO2 prices than in ERCOT where natural gas-plants typically set the electricity price. The model showed moderate CO2 emissions reductions in ERCOT with CO2 capture and no CO2 price because increased costs at coal-fired power plants led to reduced generation. Without CO2 prices, installing CO2 capture on coal-fired power plants resulted in moderately reduced CO2 emissions in ERCOT as the coal-fired power plants became more expensive and were replaced with less expensive natural gas-fired generators. Without changing the makeup of the plant fleet in NEM, a CO2 price would not currently promote significant replacement of coal-fired power plants because there is minimal excess capacity with low CO2 emissions rates that can displace existing coal-fired power plants. Additionally, retrofitting CO2 capture onto half of the coal-based fleet in NEM did not reduce CO2 emissions significantly without CO2 costs being implemented because the plants with capture become more expensive and were replaced by the coal-fired power plants without CO2 capture. Operating profits at NEM capture plants increased as CO2 price increased much faster than capture plants in ERCOT. The higher rate of increasing profits for plants in NEM is due to the marginal generators in NEM being coal-based facilities with higher CO2 emissions penalties than the natural gas-fired facilities that set electricity prices in ERCOT. Overall, coal-fired power plants were more profitable with CO2 capture systems than without in both ERCOT and NEM when CO2 prices were higher than USD25/ton.

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