1. Key Laboratory of Coal Processing and Efficient Utilization, Ministry of Education, Xuzhou, Jiangsu, 221116 China
2. School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu, 221116 China
3. Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084 China
4. Department of Mechanical & Mechatronics Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1 Canada