餐厨垃圾与剩余污泥共发酵产酸作为反硝化碳源的有效性

Availability of Acid from Co-fermentation Food Waste and Waste Activated Sludge as Carbon Source for Denitrification

在河北沧州市采用有效容积为1.5立方米的搅拌釜式反应器,对餐厨垃圾与剩余污泥进行中温(35±2℃)厌氧发酵处理中试研究。考察了共发酵过程可溶性化学需氧量(SCOD)和生化需氧量(BOD)的释放规律以及氮、磷的释放对碳源有效性的影响,同时对餐厨垃圾与剩余污泥共发酵进行经济分析。结果表明:在发酵第10天,SCOD和BOD溶出量达到稳定状态,分别为13320.0 mg/L和7510.0 mg/L;氨氮在第10天释放的最多,为192.5±2.5 mg/L,扣除发酵液中的氨氮对碳源的消耗,共发酵碳源有效性为90.4%;发酵液中释放的磷在第13天达到最高值,为195.2±11.9 mg/L,可通过在厌氧发酵液中投加氯化钙直接回收。经济成本分析表明,采用餐厨垃圾与剩余污泥共发酵产酸作为反硝化碳源时,沧州两厂每年可节省约2002.6万元。

A pilot study on anaerobic co-fermentation of food waste and waste activated sludge at medium temperature(35±2℃)was carried out in a stirred tank reactor with an effective volume of 1.5 m³in Cangzhou,Hebei Province.The release of soluble chemical oxygen demand(SCOD)and biochemical oxygen demand(BOD)and the effect of nitrogen and phosphorus on carbon source availability were investigated.At the same time,the economic analysis of the co-fermentation of food waste and waste activated sludge was carried out.The results showed that after 10 days of anaerobic co-fermentation,the amounts of SCOD and BOD reached a stable state of 13320.0 mg/L and 7510.0 mg/L,respectively.The maximum release of NH4+-N was 192.5±2.5 mg/L on the 10th day,which reduced the carbon source available to 90.4%.The released phosphorus from the co-fermentation reached the highest value on the 13th day,which was 195.2±11.9 mg/L.It can be directly recovered by adding calcium chloride to the anaerobic co-fermentation liquid.The economic cost analysis showed that the Cangzhou wastewater treatment plants could save about 20.026 million yuan per year by using the co-fermentation of food waste and waste activated sludge to produce carbon source for denitrification.