Performance of integrated gasification combined cycle power plants integrated with methanol synthesis processes

Base-load integrated gasification combined cycle (IGCC) power plants can perform load-following service by integration with a methanol synthesis process. The methanol, produced from a portion of the coal gas and stored in liquid phase, can be used for matching intermediate and peak-load demand. In this paper, the load modulation capabilities of IGCC power plants for the coproduction of electricity and methanol have been investigated. Referring to a conventional duty cycle, the main performance of power plants combining slurry-feed entrained-bed gasification and gas or liquid phase methanol synthesis has been assessed, for two different peaking electric power generation solutions. Moreover, the flexibility of these plants has been evaluated for different operating conditions, some remote from design conditions. The results of the study show that IGCC power plants combining electric power generation and methanol synthesis offer considerable scope for enhancing operating flexibility and load modulation capabilities of coal gasification power plants. The plants designed for advanced liquid phase methanol synthesis process performed best in terms of overall efficiency, plant layout and operating flexibility.