餐厨垃圾和污泥联合好氧堆肥中的氮素转化及损失

Nitrogen transformation and loss during the co-composting of food waste and sludge

采用强制通风静态好氧堆肥工艺,对餐厨垃圾和污泥进行联合堆肥化处理,探究二者不同配比对堆肥氮素转化及氮素损失的影响.以w（C）/w（N）=15～40的5组餐厨垃圾和污泥作为堆肥基质,以木屑作为调理剂进行堆肥试验.结果表明：所有堆体温度均先升高后降低,最高温度为78℃,w（C）/w（N）越高,堆体的最高温度越低,且达到最高温度的时间越长,pH先降低后升高至8.5趋于平缓,总有机碳质量分数不断降低.各堆体全氮和有机氮质量分数先升高后显著降低,铵态氮质量分数先增加后略有减少,硝态氮质量分数很低且变化不大.二者联合堆肥中氮损失27.8%～48.4%,且与投加的污泥含量呈正相关关系,氨挥发占氮损失的52.6%～80.4%,氨挥发是氮损失的主要途径,且随着堆体w（C）/w（N）的增加呈减少趋势.

A co-composting experiment of food wastes and sludge was prepared, with the forced ventilation and static aerobic composting process, to explore the impact of the process on the nitrogen transformation and loss at the different ratios of these two parts. The compost matrix were food wastes and sludge, the range of w（C）/w（N） was from 15 to 40 and this scope had 5 groups, with wood chips as the conditioners. The results showed that the compost temperature was decreasing with the increase of w（C）/w（N）, with the highest temperature being 78 ℃; pH first increased and then was reduced to 8.5, and kept fiat. The content of total organic carbon was reduced constantly. The contents of total nitrogen and organic nitrogen in each pile body decreased sig- nificantly after rising first, the content of ammonium nitrogen decreased slightly after increasing first, and the content of nitrate nitrogen was very low and showed little change. The nitrogen loss in the co-composting was 27.8%-48.4%, there was a positive correlation between the nitrogen loss rate and the content of sludge and the percentage of ammonia volatilization was 52.6%-80.4% in nitrogen loss. Ammonia volatilization was the main way of nitrogen loss and showed a trend of decreasing with the increase ofw（C）/w（N）.