PAM保水剂对生物反应器填埋场持水性能及生物活性影响研究

填埋垃圾的含水率是生物反应器填埋场中垃圾降解和渗滤液产生的重要影响因素.本文将农业上广泛应用的聚丙烯酰胺(PAM)高分子保水剂用于垃圾填埋场保水持水性能的改善,以提高填埋场微生物活性,促进有机物降解.选取了典型的非水溶性高分子保水剂JB和水溶性高分子保水剂WSN20,通过考察填埋过程中介质含水率、渗滤液产量及水质,填埋气组分和微生物活性的变化,评价保水剂种类及添加量对填埋介质持水性能和垃圾降解过程的影响.结果表明,保水剂的添加量对介质的持水能力和微生物活性具有较大的影响.适量高分子保水剂的添加可有效减少渗滤液的产生并改善其水质.其中非水溶性保水剂JB的效果尤为显著,0.1%的投加比时能使填埋装置内介质的含水率增加12%,提高填埋体系中的微生物活性3.3倍,渗滤液产生量的削减达到75.6%.

Effect of water retention agent PAM on water retention property and biological activity of bioreactor landfill

Moisture content is the main factor affecting biodegradation process as well as leachate production in bioreactor landfills. In the study, two types of polyacrylamide (PAM) water retention agents which are commercially available were selected. One is a water-soluble PAM agent designated as WSN20 and the other is a water-insoluble PAM agent designated as JB. Both were applied into landfill medium to study their function on water retention and the biological activity enhancement. During the degradation process, the variation of moisture content, quantity and quality of leachate, landfill gas and electron transport system (ETS) activity in the simulated landfill reactors were determined. Result showed that dosage and type of PAM had significant impact on the water retention property and biological activity of landfill. Water retention agent of appropriate dosage could reduce the quantity of leachate production and improve its quality simultaneously. JB showed better effect than WSN20. When the dosage of JB was 0.1% (wt/wt), the moisture content and ETS activity in the waste increased by 12% and 3.3 times, respectively, while the production of leachate significantly decreased.