城市污泥中氯苯类化合物(CBs)的堆肥处理研究

Composting treatments of chlorobenzenes(CBs) in municipal sludges

将城市污泥与稻草、木屑、玉米秸秆进行不同方式的堆肥处理,应用气相色谱-质谱仪(GC/MS)对堆肥中的5种氯苯类化合物(CBs)进行分析,为城市污泥的农业利用提供依据。结果表明,不同方式污泥堆肥中CBs的总含量(ΣCBs)在0.035～5.608mg/kg之间,依次为广州污泥稻草-翻堆>广州污泥稻草+菌种-翻堆>广州污泥稻草-连续通气>佛山污泥稻草-翻堆>广州污泥稻草-间隙通气>佛山污泥木屑-间歇通气>西安污泥玉米秸秆-自然通风>佛山污泥木屑-翻堆。各污泥堆肥中主要以个别化合物为主,其种类有所不同。ΣCBs的降解率为30.39%～92.34%,以佛山污泥木屑堆肥降解效果最好。适当的堆肥处理可以有效地降低污泥中的CBs。

Eight composting treatments including manual turning, inoculating-manual turning, continuous aeration, and intermittent aeration for municipal sludge with rice straw, wood chip and maize stalk were carried out. Chlorobenzene (CBs) in different composts were determined by gas chromatograph/mass spectrograph(GC/MS). Total contents of five CBs compounds (ΣCBs) in composts ranged from 0.035 mg/kg to 5.608 mg/kg, which decreased in the order: Guangzhou sludge mixed with rice straw by manual turning((5.608) mg/kg)>Guangzhou sludge mixed with rice straw by inoculating-manual turning(0.355 mg/kg)>Guangzhou sludge mixed with rice straw by continuous aeration(0.280 mg/kg)>Foshan sludge mixed with rice by manual turning(0.173 mg/kg)>Guangzhou sludge mixed with rice straw by intermittent aeration(0.103 mg/kg)>Foshan sludge mixed with wood chip by intermittent aeration(0.088 mg/kg)>Xi'an sludge mixed with maize stalk by aeration (0.078 mg/kg)>Foshan sludge mixed with wood chip by manual turning(0.035 mg/kg). The content of most individual CBs compounds in composts was lower than 0.10 mg/kg. Among various composting treatments, foshan sludge mixed with wood chip and aeration composting especially intermittent aeration composting treatment were more efficient to degrade CBs in municipal sludge. Suitable composting treatment for municipal sludge to reduce CBs and to ensure its safer application to agricultural land is practical.