沼渣沼液养分含量及稳定性分析

为实现沼渣沼液有效利用与管理,选取以牛粪、猪粪、鸡粪为厌氧发酵原料的沼气工程,测定了沼液、沼渣中养分含量及重金属含量,探讨了不同发酵原料沼液的养分含量随储存时间的变化规律。结果表明:鸡粪沼液中养分含量最高,总氮、总磷含量分别为5 706.23 mg/L和121.21 mg/L;猪粪沼渣中总氮含量最高,达到31 000.03 mg/kg,而鸡粪沼渣中总磷含量最高,达到23 951.02 mg/kg;猪粪沼渣中锌、铜含量以及牛粪沼渣中铜含量超标;沼液营养成分含量随储存时间的延长不断降低,两者之间呈显著负相关性,且温度越高,营养成分损失率越大,鸡粪沼液中的营养元素更易流失。该结果可为沼渣沼液的合理存放及高效施用提供理论依据。

Nutrition Contents and its Stability Analysis of #br# Biogas Residue and Slurry

To effectively use and manage the biogas slurry and residue, this paper analyzed nutrition and heavy metal contents of biogas slurry and residue in three biogas projects with different raw materials (cow dung, pig manure and chicken manure) in Beijing, ahd discused the temporal variation of nutrition contents of biogas slurry from different raw materials. The results showed that the biogas slurry from chicken manure had the highest contents of total nitrogen and total phosphorus, which were 5 706.23 mg/L and 121.21 mg/L, respectively. The contents of total potassium of the slurry from cow dung was higher than the other two. The biogas residue from pig manure had the highest contents of total nitrogen, which was 31 000.03 mg/kg, and the concentration of biogas residue from chicken manure was 23 951.02 mg/kg. The zinc and copper contents in pig manure fermentation residue and the cuprum contents in cow dung fermentation residue were above the standards for agricultural purpose. Nutrition contents in the three kinds of biogas slurry decreased constantly with the storage time, which showed significant negative correlation. Moreover, the loss ratios of nutrition contents increased as the storage temperature increased in biogas slurry. Nutrition contents of biogas slurry from chicken manure lost more easily than the two other. The results could provide theoretical basis for the biogas slurry and residue storage and its application.