未消化城市污泥与稻草堆肥过程中的养分变化研究

采用静态强制通气堆和人工机械翻堆两种试验方式对城市污泥进行堆肥处理,对堆肥过程中养分的变化规律进行了研究。结果表明,堆肥过程中全量P和全量K含量呈线性上升,氮由于以氨气形式挥发损失,全氮含量的上升幅度较小。有效磷含量在堆肥前期上升,后期则下降;速效钾含量呈不断上升趋势;水溶性全氮、铵态氮、硝态氮、有机氮和水溶性全磷、正磷酸盐形态磷、水溶性有机磷的含量在堆肥初期上升,但后期下降。污泥稻草堆肥的时间以50d左右为宜。

Nutrient Transformation in Co-composting of Undigested Sewage Sludge With Rice Straw

Land utilization is an economical and popular disposal methods of sewage sludge. But proper treatment such as composting is necessary before it is applied to land. Two different composting styles including mechanic turning and forced aeration piles were studied in the experiment. The results showed that the total contents of P and K increased continuously during composting. Total N increased less than total P and K because of ammonia volatilization. Available P increased during the first period, but they decreased during later maturing period, while available K increased continuously. Water soluble total N, -N and -N followed the similar trend than available P. It is about 50d for an appropriate composting time when composting with undigested sludge and rice straw.