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.