回料对餐厨垃圾二步法堆肥处理效果的影响

Influence of Recycled Materials on the Treatment Effect of Kitchen Waste by Two-Step Composting

为探究堆肥回料替代部分餐厨垃圾好氧堆肥调理剂的可行性,采用中试规模的达诺滚筒(DANO)动态堆肥和静态堆肥结合的二步法堆肥工艺开展试验。将锯末和稻草分别与回料混合使用,分析不同比例(0、10%、20%和30%,分别记为M1、MH1-1、MH1-2、MH1-3、D1、DH2-1、DH2-2和DH2-3)回料替代部分调理剂进行好氧堆肥的效果。结果表明:利用DANO一次堆肥可以使堆体快速升温,且添加回料可以促进升温,7个批次可以维持大于55℃堆温超过12 d;回料添加量越大,易降解有机物越低,降解速度也越慢。锯末和稻草批次平均C/N降低率分别为5.42%和40.31%。添加回料能降低堆体生物毒性(8个批次的GI分别为48.35%、66.23%、54.78%、52.43%、71.89%、80.89%、73.12%和66.86%),提高腐熟度,从而提高GI。初始C/N、回料添加量和初始含水率分别控制在19∶1~24∶1、10%~20%和55%~60%情况下,二步法堆肥成品相关核心技术指标均符合NY/T 525—2021有机肥料的要求。

In order to explore the feasibility of replacing part of the food waste aerobic composting conditioner with compost returns,a pilot-scale two-step composting process combined DANO dynamic composting and static composting was used to carry out the experiment.Sawdust and rice straw were mixed with recycled materials respectively,and the effects of different proportions(0%,10%,20%and 30%)of recycled materials(marked as M1,MH1-1,MH1-2,MH1-3,D1,DH2-1,DH2-2 and DH2-3)on aerobic composting were analyzed.The results showed that DANO could make the compost temperature rise rapidly,and the addition of recycled material could promote the temperature rise.Seven batches of DANO could maintain the compost temperature above 55℃for more than twelve days.The greater the amount of recycled material added,the lower the easily degradable organic matter,and the slower the degradation rate.The average C/N reduction rates of sawdust and straw were 5.42%and 40.31%,respectively.The addition of recycled materials could reduce the biological toxicity of the pile(The GI of eight batches were 48.35%,66.23%,54.78%,52.43%,71.89%,80.89%,73.12%and 66.86%),improve the maturity,and thus increased the GI.When the initial C/N,the amount of recycled material and the initial moisture content were controlled at 19∶1~24∶1,10%~20%and 55%~60%,respectively,the core technical indicators of the two-step composting product met the requirements of NY/T 525—2021 Organic Fertilizer.