Thermodynamic evaluation of integrated gasification combined cycle: Comparison between high-ash and low-ash coals

Abstract

Summary In the present study, a coal‐integrated gasification combined cycle power plant is simulated. A high‐ash coal and low‐ash coal are considered to compare the performance of the plant. The combined cycle is in typical commercial size with 450 MW capacity. The feeds are Tabas and Illinois #6 coals which approximately contain more than 30% and 10% ash and have higher heating values of 22.7 MJ/kg and 26.8 MJ/kg, respectively. Energy and exergy analyses are done by aspen plus® and ees, respectively. Energy analysis shows that the overall efficiencies of power plants using high‐ash and low‐ash coals are 33% and 28%, respectively. The result shows that in high‐ash case, 52 kg/s coal, 10 kg/s water, and 1050 kg/s air and in low‐ash case, 48 kg/s coal and 820 kg/s air are required for providing mentioned power, approximately. Exergy analysis shows that maximum exergy destruction is in heat recovery steam generator unit. Investigating the emissions shows that high percent of ash in the coal composition has slight effects on the IGCC pollution. Finally, from thermodynamic viewpoint, it is concluded that the high‐ash coal, like the conventional one, can be used as thermally efficient and environmentally compatible feed of IGCCs. Copyright © 2016 John Wiley & Sons, Ltd.

Hydrogen Production Technologies Overview

“…The integrations of the coal gasification with other systems have been studied by different researches [239]- [249]. Thermodynamic evaluations using the first and second law of thermodynamics have been conducted on the integrated gasification systems in their analyses [242]- [250].…”

Effect of reactant types (steam, CO 2 and steam + CO 2 ) on the gasification performance of coal using entrained flow gasifier

“…1 Currently, fossil fuels supply about 80% of the world energy demand, 2 out of which nearly 30% of total energy and 40% of electricity is generated from coal. 3,4 The critical challenge of coal-based power and chemical production is its lower thermal efficiency and higher emissions using conventional techniques. 5 Currently operated subcritical technology-based pulverised power plants' thermal efficiency is about 33% with CO 2 emission of 850 kg/ MWh e .…”

“…The global energy demand is increasing rapidly and will continue to grow in the foreseeable future 1 . Currently, fossil fuels supply about 80% of the world energy demand, 2 out of which nearly 30% of total energy and 40% of electricity is generated from coal 3,4 . The critical challenge of coal‐based power and chemical production is its lower thermal efficiency and higher emissions using conventional techniques 5 .…”

“…On the other hand, the steam‐to‐coal ratio of 1.5 was reported to be ideal while using enriched oxygen (mole fraction of 0.42) as a reactant. Arabkhalaj et al 4 reported that increasing the steam‐to‐coal ratio decreases the CGE after reaching the peak efficiency using Illinois coal. However, increasing the steam‐to‐coal ratio increases the CGE up to the oxygen‐to‐coal ratio of 0.9, where the CGE reaches the maximum before dropping.…”

Energy quality factor and exergy destruction processes analysis for chemical looping hydrogen generation by coal

“…In the traditional coal to hydrogen process, crude syngas is produced by coal gasification (CG) technology, and hydrogen is obtained after purification, water gas shift (WGS), purification and other processes. 4 However, there is an increase in the equipment investment and operation cost of the process due to CO 2 capture and H 2 purification, which promote the development of hydrogen energy industry to be more energy-efficient and economical. 5 In 1910, Messerschmitt applied for the steam-iron process (SIP) patent and proposed a process that could produce hydrogen with a purity of 100%.…”