1. Research Institute for Coal Clean and Efficient Utilization, College of Electric Power, North China University of Water Resources and Electric Power, Zhengzhou, Henan 450045, People’s Republic of China
2. State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, People’s Republic of China
3. College of Engineering, Huazhong Agricultural University, Wuhan, Hubei 430070, People’s Republic of China