油脂去除对餐厨垃圾压滤液厌氧消化的影响

Effect of grease removal on the anaerobic digestion of food waste filtrate

采用常温(25℃)厌氧消化工艺,通过设计两种不同的进料浓度和4个处理方式,研究了油脂的去除对餐厨垃圾压滤液厌氧消化产沼气的影响,并考察了消化过程中典型工艺参数pH值、挥发性脂肪酸(VFA)、CODCr、总磷等的变化规律.试验结果表明油脂对餐厨垃圾压滤液厌氧消化的产气前期有一定的抑制作用,但是整体抑制不明显.处理T1(未隔油餐厨垃圾滤液800 mL)、T2(隔油餐厨垃圾滤液800 mL)、T3(未隔油餐厨垃圾滤液500 mL)、T4(隔油餐厨垃圾滤液500 mL)的产气总量分别为:84357、55539、45031和31033 mL,其中T1的产气总量是T2的1.52倍;T3的产气总量是T4的1.45倍,结果表明餐厨垃圾滤液不需要经过隔油处理而直接可以用于厌氧消化产沼气.同时,当压滤液低浓度(T3、T4)时,产气差异小;高浓度(T1、T2)时,产气差异大.此外,在整个厌氧消化过程中,处理T1、T2、T3和T4的CODCr总去除率分别为80.44%、78.53%、79.67%和80.7%.

Two different feed concentrations and four different treatment methods were designed to study the effect of grease removal on the anaerobic digestion of food waste filtrate（FWF）.CH4 was produced by anaerobic digestion of FWF in batch reactors at normal temperature（25 ℃）,and the variation of pH values,VFA concentration,CODCr concentration and TP concentration during anaerobic digestion were all measured.The results showed that the grease inhibited the anaerobic digestion slightly in the early phase of CH4 production,but did not have any significant inhibition on the overall process of anaerobic digestion.Total CH4 production of FWF 800 mL with grease（T1）,FWF 800 mL without grease（T2）,FWF 500 mL with grease（T3） and FWF 500 mL without grease（T4） were 84357,55539,45031 and 31033 mL,respectively.The total CH4 production of T1 was 1.52 time more than that of T2,and the total CH4 production of T3 was 1.45 time more than that of T4.Therefore,it was not necessary to remove grease when FWF was applied to anaerobic digestion.And the higher initial feed concentration of FWF was,the larger the difference in CH4 production become.What′s more,CODCr removal rate of T1,T2,T3 and T4 were 80.44%,78.53%,79.67% and 80.7% respectively,in the whole process of anaerobic digestion.