利用餐厨和绿化垃圾提高蚯蚓堆肥效率处理剩余污泥的研究

为了显著提高蚯蚓堆肥处理剩余污泥的效率,在实验室条件下进行了掺入不同比例餐厨和绿化垃圾的剩余污泥蚯蚓堆肥试验。在保持剩余污泥占主体的情况下,试验按照剩余污泥：餐厨垃圾：绿化垃圾的质量比（干质量）顺序,共设6个不同配比处理组,分别为100/0/0、90/5/5、80/10/10、70/15/15、70/20/10和70/10/20,各组接种蚯蚓后恒温（25±1）℃暗室培养,中途适时补充基质和水分,试验为期7周。试验结束后,去除未被降解基质,分离并量测蚯蚓质量和数量以及蚓粪质量及其养分含量,并据此量化比较各组蚯蚓堆肥效率。试验结果表明,与纯污泥相比,增加餐厨和绿化垃圾的总比例可以显著加快蚯蚓的生长、成熟和繁殖速度,显著提高对应基质的降解速率和蚓粪生产速率,而且相应蚓粪的养分（总有机碳、全钾）含量也会显著增加（全氮和全磷含量无显著影响）。在保持剩余污泥占70%比例下,掺入15%餐厨垃圾和15%绿化垃圾的组别蚯蚓堆肥处理剩余污泥的效率达到最高（蚓粪的养分含量除外）,并与其他组别相比具有统计显著性。总之,餐厨和绿化垃圾的掺入能够显著提高蚯蚓堆肥处理剩余污泥的效率。

Improving efficiency of vermicomposting on municipal sludge by using kitchen and green wastes

In order to remarkably improving the efficiency of vermicomposting on municipal sludge, a simulated vermicomposting experiment on the mixed sludge with different ratios of kitchen wastes and green wastes was carried out in laboratory. With the major part of sludge in the mixed medium, six treatments were designed in the experiment, with different mass （dry mass） ratios of municipal sludge, kitchen wastes and green wastes, i.e., 100/0/0, 90/5/5, 80/10/10, 70/15/15, 70/20/10 and 70/10/20, respectively.After inoculated with earthworms （Eiseniafoetida）, the mixtures were cultured at （25-4-1）℃ in a dark room, and replenished with water and corresponding mixed medium based on their moisture and food consumption. After 7 weeks of culture, the unassimilated medium were removed, and the mass and number of earthworms, the wormcast mass and its nutrient content were measured and quantified, and thereby the efficiencies of vermicomposting of different treatments were compared quantitatively. Results showed that, in comparison with pure sludge, increasing the total ratio of kitchen and green wastes can increase significantly the rate of growth, mature and reproduction of earthworms, as well as the assimilation rate of corresponding medium and transformation rate of medium into earthworm manure, in which the content of total organic carbon and total potassium were also increased （but total nitrogen and total phosphorus changed insignificantly）. With 70% of sludge in the mixed medium, the efficiency of vermicomposting of the treatment mixed with 15% of kitchen wastes and 15% of green wastes reached the highest point （but not for the nutrient content ofwormcast）, and additionally, this difference was statistically significant as compared with those in other treatments. In total, the efficiency of vermicomposting on the mixed sludge can be improved significantly by mixing kitchen and green wastes with sludge.