affiliation not provided to SSRN, affiliation not provided to SSRN, Huazhong University of Science and Technology - State Key Laboratory of Coal Combustion, Singapore University of Technology and Design (SUTD), affiliation not provided to SSRN, Singapore University of Technology and Design (SUTD), Huazhong University of Science and Technology, Huazhong University of Science and Technology - State Key Laboratory of Coal Combustion and Huazhong University of Science and Technology