Parametric Optimization for Power De-Rate Reduction in the Integrated Coal-Fired Power Plant with Carbon Capture and Storage

Abstract

Carbon capture and storage (CCS) has attracted worldwide attention as a near-term technology to decelerate global warming. Postcombustion CO2 capture utilizes existing coal-fired power plants, and aqueous monoethanolamine (MEA) scrubbing is the most common capture technology. However, the heat and energy requirements of solvent regeneration and CO2 liquefaction cause a 30% decrease in net power output. This power de-rate is a major obstacle to implementing CCS. In this study, simulation-based parametric optimization was performed to minimize the power de-rate. Postcombustion CO2 capture with aqueous MEA scrubbing (85%, 90%, and 95% removals) and CO2 liquefaction integrated with a 550 MWe supercritical coal-fired power plant was simulated. The liquid to gas ratio and stripper operating pressure of the CO2 capture process were the manipulated variables with steam extracted from the intermediate pressure–low pressure crossover pipe and the first low pressure turbine as possible heat sources. The power de-rate was reduced to 17.7% when operating at optimum conditions.