死猪堆肥处理通风率的优化试验

Optimum Ventilation Rates for Pig Carcass Composting

利用箱式堆肥法对死猪堆肥处理通风率参数进行优化，试验设置通风速率为100、80、60 L·min-1·m-33组处理，每组处理3个重复。堆肥箱的长宽高尺寸均为1 m，每个箱体处理死猪质量为57.7～58.5 kg，发酵原料为猪粪和秸秆。结果表明：各处理日平均温度超过55℃的时间均达35 d 以上，满足粪便无害化的相关要求；经46 d 的堆肥发酵后，死猪仅剩余部分骨骼，3组处理的死猪降解率（湿重）分别为（95.6±1.1）豫、（94.6±2.2）豫和（96.2±1.5）豫，不同处理无显著性差异；堆肥过程不同处理的物料同一特性变化规律一致，堆肥结束时物料中粪大肠菌群数为3 MPN·g-1、pH 值为8.3～8.4、有机质含量（干基）为45.5豫～51.1豫，均满足 NY 525-2012《有机肥料》行业标准中相关技术指标的要求。死猪堆肥处理的实际应用中，选择60 L·min-1·m-3的通风率为宜。

The conventional disposal of dead animal carcasses is land burial in China. However, it poses a potential contamination risk to groundwater at burial sites. Composting carcasses not only greatly reduces the volume and mass of the wastes, but also destroys pathogens. Ventilation is a key factor influencing the composting efficiency. Here an experiment was conducted using composting bins to determine the optimum ventilation rate of dead pig composting. The dimensions of the composting bin were 1 m（length）＆#237;1 m（width）＆#237;1 m（height）. Three ventilation rates of 100 L·min-1·m-3, 80 L·min-1·m-3 and 60 L·min-1·m-3, designated respectively as treatment 1, 2, and 3, were designed with 3 replicate composting bins each treatment. Dead pigs with a total weight of 57.7～58.5 kg were put in the center of each bin containing mixture of corn stalks and pig manure. The composts obtained under average daily temperature over 55 ℃ for 45 d, 35 d, and 43 d for treat-ment 1, 2 and 3, respectively, met the national standard. The degradation rates（wet basis）of dead pigs after 46 d fermentation were（95.6±1.1）%,（94.6±2.2）% and（96.2±1.5）% for treatment 1, 2 and 3, respectively, with no significant differences observed among treatments. At the end of composting, the composts contained fecal coliform of 3 MPN·g-1, pH of 8.3 to 8.4, and organic matter（dry base）ranging be-tween 45.5% and 51.1%. All values satisfied the China National Standards for Organic Fertilizer. The ventilation rate of 60 L·min-1·m-3 for dead pig composting is recommended.