Operating the CO2 absorption plant in a post-combustion unit in flexible mode for cost reduction

Abstract

Carbon dioxide greatly contributes to climate change and its emissions must be limited.Combustion of fossil fuels in power plants to produce electricity generates the largest amount of CO2 released into the atmosphere, therefore application of Carbon Capture and Storage (CCS) to this sector would help in reducing the emissions of this acid gas.CO2 absorption with aqueous amines is the most common capture technology for postcombustion CO2 removal and is characterized by high energy requirements, mainly for CO2 release from the solvent and compression of the obtained rich-CO2 stream. For this reason operating the CCS system in a power plant significantly reduces the power output and, consequently, the revenues from selling electricity.In order to deal with this issue while maintaining low carbon dioxide emissions, flexible operation may be applied.In this work, a detailed analysis of the application of the Solvent Storage mode for flexible operation of the CO2 removal section of a natural gas combined cycle power plant has been performed.Simulations in ASPEN Plus ® , properly customized for the description of the system, and a technoeconomic model created by the GASP group of Politecnico di Milano have been run to find the best solution. The variation of price of electricity from hour to hour for key days and for the overall year have been considered. Different values of carbon tax to be applied have been also taken into account.

Fixed and Capture Level Reduction operating modes for carbon dioxide removal in a Natural Gas Combined Cycle power plant

“…The analysis cosiders as case study the possible application of CO2 capture in Italy to a power plant of 630 MW. January (generally the coldest month in this country) and July(the month with the highest variation of demand and electricity prices (Moioli and Pellegrini, 2018))…”

“…The plant in fixed operation for the absorption of 95% of the carbon dioxide present in the flue gas had been designed previously (Moioli and Pellegrini, 2018;Moioli and Pellegrini, 2019b) and has been considered for the work carried out in this paper. The design of the plant had been performed in order to treat the very huge gas flowrate in suitable and realizable columns while minimizing the energy consumption, which is located mainly at the reboiler of the regenerating column and in the compression section.…”

“…Li et al (Li et al, 2013) analyzed more than 1000 patents on absorption, adsorption and membranes and concluded that there are no practical processes for removing carbon dioxide from large CO2 sources with low added Cost of Electricity (COE). Mondal et al (Mondal et al, 2012) presented a comparative analysis of different technologies and considered emergin technologies including enzymes, facilitated transport membranes and hydrate based separation.…”

Sustainability Analysis for the Wastewater Treatment Technical Route for Coal-to-Synthetic Natural Gas Industry through Zero Liquid Discharge Versus Standard Liquid Discharge

“…According to our economic analysis results, the ZLD route is not economical compared to the SLD route. The same occurs also for carbon dioxide removal from flue gases from power plants to reduce the global warming effect because of the CO 2 emissions to the atmosphere. − Therefore, if China had not enforced a ZLD policy, enterprises in China would not have chosen the ZLD route because of the costs.…”

Novel Machine Learning Model Correlating CO2Equilibrium Solubility in Three Tertiary Amines

“…PCCC using amine-based reactive solvents has been proven to be a promising technology to address the climate change problem in the immediate future. − The amine solvent is commonly regarded as one of the significant factors and dominates the energy consumption of a carbon capture plant. Different solutions have been proposed to diminish the energy consumption, such as optimizing the process flowsheet, process modifications or intensification, and alternative solvents. − Among them, the development of potential solvents is treated as an essential approach to the target of reducing energy requirement. By obtaining new amines with promising performances such as a high cyclic capacity, a fast reaction rate, and low heat duty, the energy requirement of the PCCC process could be expected to further decrease. − …”