title: Comparative Assessment of Gasification Based Coal Power Plants with Various CO2Capture Technologies Producing Electricity and Hydrogen.
abstract: Seven different types of gasification-based coal conversion processes for producing mainly electricity and in some cases hydrogen (H2), with and without carbon dioxide (CO2) capture, were compared on a consistent basis through simulation studies. The flowsheet for each process was developed in a chemical process simulation tool "Aspen Plus". The pressure swing adsorption (PSA), physical absorption (Selexol), and chemical looping combustion (CLC) technologies were separately analyzed for processes with CO2capture. The performances of the above three capture technologies were compared with respect to energetic and exergetic efficiencies, and the level of CO2emission. The effect of air separation unit (ASU) and gas turbine (GT) integration on the power output of all the CO2capture cases is assessed. Sensitivity analysis was carried out for the CLC process (electricity-only case) to examine the effect of temperature and water-cooling of the air reactor on the overall efficiency of the process. The results show that, when only electricity production in considered, the case using CLC technology has an electrical efficiency 1.3% and 2.3% higher than the PSA and Selexol based cases, respectively. The CLC based process achieves an overall CO2capture efficiency of 99.9% in contrast to 89.9% for PSA and 93.5% for Selexol based processes. The overall efficiency of the CLC case for combined electricity and H2production is marginally higher (by 0.3%) than Selexol and lower (by 0.6%) than PSA cases. The integration between the ASU and GT units benefits all three technologies in terms of electrical efficiency. Furthermore, our results suggest that it is favorable to operate the air reactor of the CLC process at higher temperatures with excess air supply in order to achieve higher power efficiency.
authors.affiliation: Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences (FEPS), University of Surrey , Guildford, Surrey GU2 7XH, United Kingdom.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences (FEPS), University of Surrey , Guildford, Surrey GU2 7XH, United Kingdom.
authors.forename: Prashant
authors.initials: P
authors.lastname: Kumar
authors.affiliation: Sharif Energy Research Institute (SERI), Sharif University of Technology , Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Hosseini
authors.affiliation: Department of Chemical and Process Engineering, FEPS, University of Surrey , Guildford, Surrey GU2 7XH, United Kingdom ; Department of Engineering Science, University of Oxford , Parks Road, Oxford OX1 3PJ, United Kingdom.
authors.forename: Aidong
authors.initials: A
authors.lastname: Yang
authors.affiliation: Department of Chemical Engineering, Imperial College London , South Kensington, London SW7 2AZ, United Kingdom.
authors.forename: Paul
authors.initials: P
authors.lastname: Fennell