西北半干旱区蚯蚓堆肥对污泥理化性质的影响

Effect of Vermicomposting on Physico-chemical Properties of the Sewage Sludge in Northwest Semi-arid Areas

[目的]为西北半干旱地区城市污泥资源化利用提供科学依据。[方法]以兰州为例研究西北半干旱区蚯蚓堆肥直接处理新鲜脱水城市污泥并探讨堆肥过程中污泥理化性质的动态变化。[结果]堆肥过程中pH值趋于中性,最终降至7.02,EC值增加,最终增加了2.79倍;堆肥产物中的有机质含量明显降低,最终降低了34.29%;速效氮、速效磷和速效钾含量总体呈增加趋势,分别增加了87.83%、66.36%和19.28%。[结论]可见,在西北半干旱区城市污泥蚯蚓堆肥实现了城市污泥的稳定化,使得城市污泥中营养元素的植物利用有效性提高。

[ Objective ] The aim was to provide a scientific basis for the reuse utilization of sewage sludge in northwest semi-arid areas. [ Method] The variation of physical and chemical properties in the fresh dewatered sewage sludge during vermicomposting was studied in north- west semi-arid areas as a case of Lanzhou city. [ Results] As a result, at the end of the experiment, the pH value closed to 7 and declined to 7.02, but the EC values increased by 2.79 times ; the organic matter content of the vermicomposting product was significantly reduced and de- creased by 34.29% ; and the content of available nitrogen, phosphorus and potassium as a whole increased by 87.83%, 66.36% and 19. 28%, respectively. [ Conclusion] Thus, the vermicomposting process could lead to the stabilization of the sewage sludge and the improve- ment of the availability of nutritional elements for plant growing in the vermicomposting products in northwest semi-arid areas.