城市生活垃圾工厂化堆肥过程中理化指标的变化研究

以马家楼转运站前处理垃圾和南宫堆肥厂堆肥过程中的垃圾堆肥为研究对象,对其物理组成、营养元素及重金属等理化指标的变化进行了研究。结果表明,混合收集垃圾经马家楼转运站前处理后,只能达到粒径分选,不能使无机组分和有机组分、硬物料和轻物料分选,>60mm、<15mm和15～60mm各部分中各种垃圾组分依然存在;15～60mm的堆肥原料中,可堆腐物质含量为68.3%～82.72%。堆肥过程中,总氮呈下降趋势;钾的含量稳中有降;磷和其它营养元素(Ca、Mg、Na、Fe、Mn)含量呈增加趋势。垃圾堆肥过程中重金属的含量呈增加趋势,但腐熟堆肥中重金属Cd、Pb、Cr的含量均远远低于垃圾农用卫生标准(GB8172—87)。

Variations of Physical and Chemical Indexes During MSW Plant-scale Composting

Using pre-treatment MSW from Majialou sorting station and MSW compost from Nangong Compost Plant as testing materials,the physical and chemical indexes were studied.The garbage could be screened only according to granularity in the pre-treatment in Majialou sorting station,but organic and inorganic components,hard and soft materials in MSW could not be separated.The percentage of degradable components in the composting materials with granularity 15~60 mm was 68.3%~82.72%.During the composting,total nitrogen(TN)tended to decrease,while the contents of P,nutrient element(Fe,Ca,Mg,Zn,Cu and Mn)and the heavy metals(Cd,Pb and Cr)increased.The contents of heavy metals in the MSW compost were lower than those recommended in the National Standards on use in agriculture(GB 8172-87).