畜禽粪便厌氧发酵的产气特点及其发酵物养分的变化动态

Biogas Generation from Anaerobic Fermentation of Animal Manures and Nutrient Dynamics in Residues

为弄清不同畜禽粪便的产气特点及其发酵物养分含量的变化,利用高效曲流布料发酵池厌氧发酵,对其进行了研究。结果表明:猪粪、鸡粪和牛粪干粪便的产气时间分别为150、90和90 d,产气量分别为250、150和70 m3,最大甲烷含量分别为76.1%、79.9%和62.0%。发酵物养分含量变化,3种粪便厌氧发酵后养分含量的变化趋势一致,发酵物中大多数氮以氨态氮形式存在,NH4+浓度在水解阶段后随着发酵进程递增,NO3-浓度呈下降趋势。发酵过程中养分不断被消化和溶解,沼液中所有养分含量呈增加趋势,而沼渣中养分含量呈减少趋势,但沼液中的磷含量较低。

In order to figure out the biogas generation features of different domestic animal manures, determine the nutrient dynamics in both biogas liquid residues （BLRs） and biogas solid residues （BSRs） during the fermentation, and provide academic basis for household biogas production and organic crop production, pig, chicken, and cow manures were fermented in the fixed dome digesters in this study. The resuits showed that from 1000 kg dry matter, the duration of biogas production farm pig, chicken, and cow manures was 150, 90, and 90 days, and gas volume was 250, 150, and 70 m^3 with maximum CH4 compositions of 76.1%, 79.9 %, and 62, 0 %, respectively. Nutrient dynamics were analyzed regularly and it was found that all manures had similar nutrient dynamics but cow manure BLR had a lower N content. Most of the N in all the BRs was in NH4^＋ form. NH4^＋ increased in all the BLRs while NO3^- decreased after the hydrolysis phase due to the absence of 02. All other nutrients increased in the BLRs but decreased in the BSRs due to the digestion and dissolution into the BLRs. Available P was relatively low in all the BLRs.