Energy and cost efficient manganese chemical looping air separation cycle for decarbonized power generation based on oxy-fuel combustion and gasification

Oxy-fuel combustion and gasification technologies for power generation require significant oxygen consumption. The actual oxygen production method involves cryogenic systems, the most important shortcomings of this process are high ancillary electricity consumption and high capital costs. Chemical Looping Air Separation (CLAS) concept represents an emerging oxygen generation option with significantly lower energy consumption. The present work is evaluating the key performance indexes of manganese-based CLAS unit to be combined with coal and lignite oxy-fuel and gasification power plants. As comparison cases, the same power generation designs were assessed using conventional cryogenic air separation. The evaluations considered large industrial scale power plants with about 370-500 MW net electricity production and a 90% overall plant decarbonisation degree. The detailed investigations demonstrated that manganese-based looping cycle improves significantly the main techno-economic performances compared to the benchmark cases e.g. higher energy efficiency up to 9%, lower specific CO2 emissions down to 10%, reduced overall plant energy penalty for decarbonisation by 2-3.5 net electricity percentage points, decreased capital costs by 10-18% and electricity cost by about 7-12% etc. (C) 2019 Elsevier Ltd. All rights reserved.