水泡粪物料中固体和氨氮含量对厌氧消化产气特性的影响

Effects of the Characteristics of Deep-pit Effluent on Anaerobic Digestion of Swine Manure

目前不少猪场使用水泡粪清粪工艺清理猪粪便,同时对水泡粪清理的粪污进行沼气工程处理,但不同水泡粪贮存条件对其粪污后续厌氧发酵的影响尚不清楚.本试验将猪粪和尿液通过不同贮存温度（20℃,30℃）和时间（7d,14d,21d）组成6种前处理条件,模拟不同条件水泡粪出水,研究水泡粪物料特性对出水厌氧发酵的影响.结果表明,水泡粪出水的单位挥发性固体（VS）的厌氧发酵产气率在369.2 ～702.0mL/g,厌氧发酵前7d的日产沼气量一直处于较高水平,之后快速下降,厌氧发酵10d后产气基本处于较低水平且下降平缓;氨氮对厌氧发酵有显著的抑制作用,厌氧消化甲烷产率（y）与氨氮浓度（x）的关系为y =4＆#215;10-5x2-0.3618x＋1283（R2=0.9846）.水泡粪物料总固体物含量越高厌氧发酵产气越低,据此建议适当缩短水泡粪时间以提高后续厌氧发酵产气量.

Deep-pit system is a commonly used method for swine manure collection, and the collected waste is then trea- ted using biogas engineering. However, there is a lack of information about the effects of deep-pit conditions on the fol- lowing anaerobic digestion of the effluents. In this study, swine manure and urine were collected and mixed, and the mixture was stored under six different condition formed by 3 storage temperatures of 20℃ and 30℃ and 3 storage times of 7,14 and 21d to produce deep-pit effluents,which were used as suhstrate to investigate the effects of the characteris- tics of deep-pit effluents on anaerobic digestion. The results showed that the daily averaged methane production rate （MPR） of the deep-pit effluents ranged from 369.2 to 702.0mL/g ,and the daily average MPR kept at high level during the first 7 days into trials, and then dropped rapidly and reached a lower level on the 10 clays of digestion process, after that the daily average MPR kept at relatively lower level and decreased very slowly. Ammonia nitrogen exhibited inhibi- tion effects on MPR, and the relation between methane yield per VS and ammonia nitrogen could be expressed as y = 4 ×10-5x2 -0. 3618x ＋ 1283 （R2 = 0.9846）. The higher the TS content of deep-pit effluent, the lower methane production. Therefore, it is possible to improve methane production of anaerobic .digestion via shortening the storage period of swine manure in deep-pit.