不同发酵方式对鸡粪重金属及有机质影响

Heavy metal and organic matters in the chicken manure under different types of composting.

以鸡粪和稻草秸秆为原料,研究了一次堆肥发酵(包括液体菌剂发酵,L;固体菌剂发酵,S;高温酵素发酵,E),以及连续二次堆肥发酵(高温酵素发酵+液体菌剂发酵,EL;高温酵素发酵+固体菌剂发酵,ES)下有机肥中重金属含量和形态分布规律、理化性质以及有机质变化特征.结果表明,与堆肥前相比,堆肥后鸡粪有机肥pH值显著增加(P<0.05),而EC值和含水率均显著减少(P<0.05).小白菜种子发芽率由堆肥前的高达58.1%下降到堆肥后小于20%.堆肥后重金属由可溶态向难降解残渣态转化,有机肥中Cu、Zn、Cr、Cd、Pb和As钝化率分别达到27.2%~69.3%、17.1%~50.7%、24.0%~68.7%、16.9%~46.3%、33.1%~54.3%和0.4%~29.5%.腐殖物质和胡敏酸含量显著增加(P<0.05),胡敏酸/富里酸(HA/FA)比值均上升.堆肥中多糖类和脂肪族化合物含量均有所增加,但香族类化合物有所降低.从重金属钝化率、有机肥腐熟度等有机肥无害化指标来看,连续二次发酵效果优于一次发酵,其中EL效果最佳.

Using chicken manure and straw as raw materials,with one time composting fermentation(including liquid fermentation,L;solid bacterial fermentation,S;high temperature enzyme fermentation,E),and continuous-composting-fermentation(high temperature enzyme fermentation+liquid bacteria Fermentation,EL;high temperature enzyme fermentation+solid bacterial fermentation,ES)to study heavy metal content and morphology distribution,physical and chemical properties and organic matter changes.The results showed that the pH value of chicken manure organic fertilizer increased significantly after composting(P<0.05),while the EC value and water content decreased significantly(P<0.05).The germination rate of Chinese cabbage seeds decreased from 58.1%before composting to less than 20%after composting.After composting,heavy metals were transformed from soluble state to refractory residue state,and the immobilization rates of Cu,Zn,Cr,Cd,Pb and As in chicken organic fertilizer reached 27.2%~69.3%,17.1%~50.7%,24.0%~68.7%,16.9%~46.3%,33.1%~54.3%and 0.4%~29.5%,respectively,when compared with CK.The content of humic substances and humic acid was significantly increased(P<0.05),and the ratio of humic acid/fulvic acid(HA/FA)was enhanced.The amount of polysaccharides and aliphatic compounds after composting was increased,while the aroma compound was reduced.In view of the harmlessness index of organic fertilizer such as heavy metal immobilization and organic fertilizer maturity,the effect of continuous-fermentation was better than that of once-fermentation,and the EL treatments was the best.