1. State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Biogas Upgrading Utilization, College of New Energy and Materials, China University of Petroleum Beijing (CUPB), Beijing 102249, P. R. China
2. China Huadian Engineering Co., Ltd., Beijing 100081, P. R. China
3. NIBIO, Norwegian Institute of Bioeconomy Research, P.O. Box 115, N-1431 Ås, Norway
4. Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, P. R. China
5. College of Information Science & Technology, Beijing University of Chemical Technology, Beijing 100029, China