过滤后养猪废水厌氧发酵与固氮技术研究

为探究养殖废水高效处理方法,文章采用粉碎玉米秸秆过滤养殖废水中悬浮性固体,并对过滤后养猪废水作厌氧发酵和固氮研究。经过滤,总固体(TS)去除率达47.55%,在中温(35±2)℃条件下,研究5、15、25 d 3种不同水力停留时间(HRT),过滤后养猪废水全混合厌氧发酵特性。厌氧发酵过程运行稳定,产生沼气甲烷含量均稳定在70%左右,当水力停留时间为15 d时,产甲烷效率为239.17 mL CH4/gVS,溶解性化学需氧量(SCOD)去除率60.94%。沼液采用鸟粪石沉淀法固氮处理,经过试验参数优化在物质的量比n(Mg2+)n(PO43-):n(NH4+)=1.021.061、pH为9.6条件下,氨氮(TAN)去除率达86.66%,处理后沼液中氨氮浓度为160 mg·L-1,研究结果可为养猪废水资源化利用提供参考。

Study on anaerobic fermentation and nitrogen fixation technology of filtered pig wastewater

In order to explore the efficient treatment method of aquaculture wastewater.Pulverized corn straw was used to filter suspended solids in aquaculture wastewater, and anaerobic fermentation of filtered swine wastewater. After filtering, removal rate of suspended solids reached47.55%. Under the conditions of(35±2) ℃ and 5, 15 and 25 d, three different hydraulic retention time(HRT) conditions were studied. The anaerobic fermentation process run stably, and the methane content that produced biogas was stable around 70%. When the hydraulic retention time was 15 days,the methanogenesis efficiency was 239.17 mL CH4/gVS, and the removal rates of dissolved chemical oxygen demand(SCOD) was 60.94%. Biogas slurry was treated with struvite precipitation method optimized by response surface method. Optimized by experimental parameters under the condition of amount of substance ratio n(Mg~(2+)) n(PO_4~(3-)): n(NH_4~+) = 1.02:1.06:1, pH was 9.6, the ammonia nitrogen(TAN) removal rate reached 86.66%, and the ammonia nitrogen concentration in the biogas slurry after treatment was 160 mg· L~(-1). The research results have a good reference value for the resource utilization of pig wastewater.