Research On CO₂ Capture With Low Energy Consumption Based On IGCC Power Generation System

Currently, the growing global warming problem has caused the world concern about the reduction of greenhouse gas emissions such as CO2. Improving the utilization efficiency of fossil fuels, and capturing CO2 during the utilization process are two important measures to reduce CO2 emission. IGCC power generation technology is considered as the cleanest coal-fired power generation technology in the world, however, it can be real clean plant only if the CO2 emission problem can be solved. Based on the traditional IGCC system without CO2 capture, this paper studies a zero-CO2 emission IGCC system integrated with oxygen transport membrane (OTM), and two hybrid systems with CO2 capture by integrating molten carbonate fuel cell (MCFC), solving the CO2 emission problem of IGCC system under the premise to ensure system efficiency.Firstly, this paper introduces the process of IGCC power generation system and different CO2 capture methods based on IGCC system, then uses Aspen Plus software to establish the whole process model of IGCC system and get the accurate logistics data and system performance parameters.Secondly, based on the traditional IGCC system without CO2 capture, three different zero-CO2 emission power generation systems are put forward. The first one is a zero-CO2 emission IGCC system integrated with OTM, which is based on the oxy-fuel combustion method to capture CO2 and uses the OTM unit instead of the traditional cryogenic air separation unit to separate oxygen. The second one is an integrated coal gasification molten carbonate fuel cell combined cycle (IGMCFCCC) system, in which the gas turbine unit of traditional IGCC system is replaced by MCFC unit, thus a new IGMCFCCC system with CO2 capture is proposed. The third one is a new IGCC system with CO2 capture by integrating MCFC. Through contrast with the reference system and optimization analysis of their key performance parameters, results show that the new systems have obvious advantages in energy saving.Achievements from this paper lay a theoretical foundation for the design of new IGCC systems with high efficiency and low CO2 emission, and provide new ideas and approaches for the implementation of energy saving strategies for power generation systems.