Influence of Anaerobic Fermentation Periods, Storage Time and Filtration on the Changes of Nutrients and Physical and Chemical Properties of Biogas Slurry

• Main Authors: ZHAGN Li-ping, LIU Hong-jiang, SHEGN Jing, CHEN Liu-gen, ZHENG Jian-chu
• Format: Article
• Language: zho
• Published: Agro-Environmental Protection Institute, Ministry of Agriculture 2017-12-01
• Series: Journal of Agricultural Resources and Environment
• Subjects: anaerobically digested pig slurry, storage, nutrient change, filtration
• Online Access: http://www.aed.org.cn/nyzyyhjxb/html/2018/1/20180105.htm

In order to realize the effective utilization and management of biogas slurry, according to the actual production situation of biogas slurry anaerobic fermentation, the simulated fermentation experiment was carried out in view of the extensive anaerobic fermentation mode and the long-term storage of biogas slurry in actual production. The treatments were carried out in five different fermentation cycles(at 2, 4, 6, 8, 10 d,respectively) and the pig manure raw materials were discharged at this time point for producing biogas slurry. Then the nutrient contents and physical and chemical property varieties such as COD, pH, TN, TP and TK were studied during storage, as well as the impact of screen filter on nutrients and physical and chemical properties of biogas slurry. The results showed that the contents of TN and TP in the five kinds of biogas slurry decreased by 40.9%~46.31% and 35.62%~53.61%, respectively with the increase of fermentation period and storage time, the content of TK showed a slight increase with time, but the increase remained stable. During the storage period, the contents of ammonium nitrogen decreased gradually which decreased by almost 62% after 14 days. In contrast, the nitrate nitrogen contents increased gradually. The COD decreased by 69.97%~85.86% and the pH value of all the biogas slurries were increasing from 7.6~7.9 to 8.2~8.7. The nutrient contents, COD and pH value of the biogas solution were not significantly different after filtering through different aperture screen, so the filtration would not affect the nutrient storage of biogas.