应用生物炭改善填埋场渗滤液的厌氧消化性能

为了评估填埋场新鲜渗滤液的厌氧消化性能以及探索强化其厌氧消化性能的措施，采用了低、中、高三种食微比（分别为0.49，1.02，1.92g渗滤液COD/g污泥VS），并在高食微比时，比较了分别添加<5μm、75~150μm、2~5mm的木炭以及75~150μm的竹炭对渗滤液厌氧消化过程的影响.结果表明，高食微比时渗滤液的甲烷化启动严重滞后，且运行不稳定.在高食微比时，与未添加生物炭的对照组相比，添加<5μm、75~150μm、2~5mm的木炭组以及75~150μm的竹炭组，最大产甲烷速率分别提高了179%、93%、83%和64%，最终出水溶解性氮分别下降了21%、16%、16%和12%，NH₄⁺-N分别下降了17%、12%、10%和8%；并且<5μm的木炭组的有机物和有机酸降解，尤其是正丁酸和乙酸的降解，显著快于其他粒径的木炭组.这些结果说明生物炭可以提高渗滤液的厌氧消化效率和工艺稳定性，对于木炭，粒径越小，效果越显著.

Application of biochar to improve anaerobic degradation of landfill leachate

In order to evaluate the treatment efficiency of fresh landfill leachate by anaerobic digestion, and to explore the measures to improve the efficiency and process stability, the present study assessed the effect of low, medium and high food to microorganism ratio (F/M) (i.e., 0.49, 1.02 and 1.92g-leachate COD/g-sludge VS). Meanwhile, wood chars of <5μm, 75~150μm and 2~5mm, and bamboo biochar of 75~150μm were added at high F/M, and compared for their effects on the anaerobic digestion of leachate. The results showed that the leachate methanation was seriously delayed and the operation was unstable at high F/M. Compared with the control group without biochar addition at high F/M, the maximum methane production rate was increased by 179%, 93%, 83% and 64%, the total effluent dissolved nitrogen was decreased by 21%, 16%, 16% and 12%, and the NH₄⁺-N of the total effluent was decreased by 17%, 16%, 16% and 12%, respectively, for the scenarios of adding wood char of <5μm, 75~150μm, 2~5mm and bamboo biochar of 75~150μm. The degradation of organic matters and organic acids, especially the degradation of n-butyric acid and acetic acid in the <5μm wood biochar group, was significantly faster than that of other biochar groups. These results show that biochar can improve the efficiency and process stability of leachate anaerobic degradation. For wood biochar, the smaller the particle size was, the better performance was.