Introduction is made for three main types of purification and drying systems in air compressor station of coking industry，i.e.waste heat regeneration，micro-heat regeneration and heatless regeneration.Comparison is also made for the three purification and drying systems in aspects of compressed air yield，power consumption，water consumption，air consumption for the internal system，investment，land occupation and operating cost，etc.，which would be used as reference in final decision for selecting the system in project.