CO2 capture in advanced power plants fed by coal and equipped with OTM

• OTMs are not costly as ASUs and they do not require large energy for oxygen production as ASUs.
• In the IGCC power plant equipped with OTM, there are two membranes, M1 and M2.
• Retentate stream of M1 is purified in M2 in order to provide N2 for NOx abatement.
• In the USC power plant equipped with OTM, oxygen is produced without sweep gas.
• In the USC power plant, very hot oxygen goes directly in the fossil fuel boiler.

Greenhouse gas emissions from human activities contribute greatly towards climate change. In the power generation sector, where fossil fuels are extensively used, these emissions could be reduced by capturing and storing the CO2 emitted. Between the different fossil fuels, coal is very interesting from an economic point of view (coal reservoirs are abundant and distributed homogenously on the earth) even if it produces a lot of carbon dioxide emissions.In this paper we have studied energy and economic performance of an integrated gasification combined cycle power plant (IGCC power plant equipped with an oxygen-blown gasifier) with CO2 capture based on the pre-combustion process and an advanced supercritical steam cycle (SSC) power plant with CO2 capture based on oxy-fuel combustion process. In these power plants great oxygen flow rates are necessary and so we have chosen an innovative technology for oxygen production based on oxygen transport membranes. The goal of this paper is the discussion of the main characteristics and performance of these membranes and the analysis of their integration in advanced coal-fired power plants. For each power plant, a full plant heat and mass balance is calculated in order to compare energy and environmental performance (net efficiency and CO2 specific emissions) and to evaluate the economic impacts of such CO2 emission abatement technologies.