Chin.J.Chem.Eng. ›› 2015, Vol. 23 ›› Issue (5): 847-852.doi: 10.1016/j.cjche.2015.03.001


Biogas by two-stage microbial anaerobic and semi-continuous digestion of Chinese cabbage waste

Xiaoying Dong1, Lijie Shao2, Yan Wang3, Wei Kou2, Yanxin Cao2, Dalei Zhang2   

  1. 1 College of Engineering, Shenyang Agriculture University, Shenyang 110000, China;
    2 Liaoning Institute of Energy Technology, Yingkou 115000, China;
    3 MAHLE Engine Components Co., Ltd. Piston Ring Plant, Yingkou 115000, China
  • Received:2014-09-03 Revised:2015-01-14 Online:2015-05-28 Published:2015-06-26
  • Contact: Dalei Zhang
  • Supported by:

    Supported by theNational Science-Technology Support Plan of China (2014BAD02B04).

Abstract: Anaerobic digestion of Chinese cabbage waste was investigated through a pilot-scale two-stage digester at a mesophilic temperature of 37 ℃. In the acidification digester, the main product was acetic acid, with the maximum concentration of 4289 mg·L-1 on the fourth day, accounting for 50.32% of total volatile fatty acids. The oxidation reduction potential (ORP) and NH4+-N level decreased gradually with hydraulic retention time (HRT) of acidification. In the second digestion phase, the maximum methanogenic bacterial concentration reached 9.6×1010 ml-1 at the organic loading rate (OLR) of 3.5-4 kg VS·m-3, with corresponding HRT of 12-16 days. Accordingly, the optimal biogas production was 0.62 m3·(kg VS)-1, with methane content of 65%-68%. ORP and NH4+-N levels in the methanizer remained between -500 and -560 mV and 2000-4500 mg·L-1, respectively. Methanococcus and Methanosarcina served as the main methanogens in the anaerobic digester.

Key words: Anaerobic digestion, Semi-continuous, Two-stage, Biogas, Chinese cabbage waste, Microbial ecology