1. School of Environment and Civil Engineering, Jiangnan University, No. 1800, Lihu Avenue, Wuxi, Jiangsu Province 214122, PR China
2. Jiangsu Key Laboratory of Anaerobic Biotechnology, Jiangnan University, No. 1800, Lihu Avenue, Wuxi, Jiangsu Province 214122, PR China
3. Department of Environmental Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark
4. Carlsberg Research Laboratory, Bjerregaardsvej 5, 2500 Valby, Denmark