Application and development of biogas technology for the treatment of waste in China

• Published in: Renewable & sustainable energy reviews Vol. 70; pp. 845 - 851
• Main Authors: Deng, Liangwei, Liu, Yi, Zheng, Dan, Wang, Lan, Pu, Xiaodong, Song, Li, Wang, Zhiyong, Lei, Yunhui, Chen, Ziai, Long, Yan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2017
• Subjects: Biogas plants; Biogas septic tanks; China; Household-scale digesters; Waste; Biogas plants; Biogas septic tanks; Household-scale digesters; Waste; China
• ISSN: 1364-0321; 1879-0690
• DOI: 10.1016/j.rser.2016.11.265

China has a long history of utilizing biogas technology for the treatment of waste and the production of energy. This paper reviews the development and technology of the three types of biogas digesters used in China: household-scale digesters, biogas septic tanks, and biogas plants for the treatment of municipal, industrial, and agricultural waste. The structure of household-scale digesters is simple and practical; the basic type is the fixed-dome digester, also called the hydraulic digester. The biogas septic tank for sewage treatment is a combination of the traditional digester, an anaerobic filter, and a facultative filter. Biogas plants apply several different processes depending on the type of waste treated. The treatment of municipal waste biogas is conducted using the completely stirred tank rector (CSTR). The upflow anaerobic sludge blanket (UASB) is the most common technology used in the anaerobic treatment of industrial wastewater, followed by the CSTR and the anaerobic contact (AC) process. The treatment of agricultural waste mainly employs traditional hydraulic digesters, while newer biogas plants use advanced anaerobic processes such as CSTR and UASB as well as upflow solids reactors (USR) and upflow blanket filter (UBF) reactors. Biogas plants for agricultural waste are classified as small, medium, large and super large based on the scale of biogas production and digester volume. Although small-scale biogas plants are the most common, large-scale biogas plants produce the largest biogas output. With the changes associated with socio-economic development, the growth of household-scale digesters will slow down in the future. As central sewage treatment networks become more widespread, biogas septic tanks will be confined to villages and small towns. The development of biogas plants holds the most growth potential for the future.