Analysis of Hybrid Configuration of Coal-Based Methanol-Power Polygeneration System

Abstract

A novel hybrid configuration of a coal-based polygeneration system, which bears the configuration characteristics of both parallel and sequential polygeneration systems, is proposed and investigated. Due to its configuration characteristics, the new system performs flexible production distribution (power and methanol) to coordinate the performance and capacity ratio of chemical to power and facilitate peak shaving of power generation. The performance of the new system is simulated by means of Aspen Plus. The new system has a wider range of product capacity than the sequential polygeneration system, with a range of energy saving rate of 2~14%. Compared with the two other polygeneration systems the new system has better performance at each capacity ratio. Especially at a capacity ratio of chemical production to power generation of 0.5, it is about 2% higher than sequential polygeneration system and 4.5% higher than the parallel polygeneration system. Exergy analysis is performed. Better chemical energy utilization of the syngas is obtained without component adjustment but with proper recycling of the unreacted gas.