Proposed Process and Design Considerations for Air Separation and CO2 Purification in a 100 MWe Oxy–Coal Power‐Generation System

system includes the planned replacement of the Youngdong Unit 1 boiler, which was designed to fire domestic high-ash anthracite (ca. 32 % ash content) assisted by heavy oil, with a new boiler with dual-combustion capability. Air–oxy dual mode means that the combustion system operates either in the conventional air-fired mode or in the oxy-fired mode to give operational flexibility as a CO2-capture-ready plant. It is expected that the plant will demonstrate CCS capability for the designated period (lifetime of the project), but continuous operation would only be allowed if the economics of the situation are favorable. This paper describes the considerations of the air-separation process for the O2-supply and CO2-purification processes of a conceptual oxy–coal combustion system for 100 MWe power generation and proposes feasible process diagrams of an ASU and CPU. Furthermore, the proposed designs are evaluated by the major performance parameters, such as power consumption for air separation and CO2 purification, and techniques for the optional integration of the ASU, boiler, and CPU into an integrated CO2 capture and storage facility are discussed. Oxy–coal combustion is one of the most promising approaches for carbon capture and storage associated with large-scale coal-fired power stations. This paper presents the results of a study on air-separation and CO2-purification processes in terms of a conceptual design for an oxy–coal combustion system for 100 MWe (electrical) power generation. Feasible processes and design considerations for air separation and CO2 purification are proposed that take into account the operational stability of the overall plant before its demonstration. Air separation by using a double column, which has two main air compressors, to produce 95 % purity gaseous O2 is proposed. Two possible cases for cryogenic separation according to the phase of the captured CO2 are considered. In addition, we consider the installation and management of the air-separation and CO2-purification units to demonstrate the 100 MWe oxy–coal power plant and methods to reduce power consumption in the processes.