Aged refuse enhances anaerobic digestion of waste activated sludge
Aged refuse enhances anaerobic digestion of waste activated sludge
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老化垃圾增强废弃活性污泥的厌氧消化
DOI：
10.1016/j.watres.2017.07.026
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发表时间：
2017
期刊：
影响因子：
12.8
通讯作者：
Yang Qi
中科院分区：
文献类型：
--
作者：
Zhao Jianwei;Gui Lin;Wang Dongbo;Li Xiaoming;Xu Rui;Zeng Guangming;Yang Qi
在这项工作中，一种低成本的替代方法（即，在剩余活性污泥中添加矿化垃圾（AR），可显著提高污泥的厌氧消化率。试验结果表明，随着AR投加量从0增加到400 mg/g干污泥，消化5 d时，溶解性化学需氧量（COD）从1150增加到5240 mg/L，挥发性脂肪酸（VFA）的最大产量从82.6增加到183.9 mg COD/g挥发性悬浮物。虽然AR添加量的进一步增加降低了可溶性COD和VFA的浓度，但在这些系统中，它们的含量与AR添加在任何浓度下的研究仍然高于空白，这导致在这些系统中更高的甲烷产率。机理研究表明，适当的添加AR促进增溶，水解和产酸过程，并没有显着影响产甲烷。结果表明，厌氧消化系统中酶的多样性和厌氧微生物的多样性是厌氧消化能力增强的主要原因。腐殖物质有利于水解和产酸，但抑制产甲烷。AR中重金属对污泥厌氧消化的影响具有剂量依赖性。适量的重金属对污泥厌氧消化有促进作用，过量的重金属对污泥厌氧消化有抑制作用。在添加AR的系统中，负责污泥水解和产酸的微生物的相对丰度也得到了改善，这与厌氧消化的性能是一致的。
In this work, a low-cost alternative approach (i.e., adding aged refuse (AR) into waste activated sludge) to significantly enhance anaerobic digestion of sludge was reported. Experimental results showed that with the addition dosage of AR increasing from 0 to 400 mg/g dry sludge soluble chemical oxygen demand (COD) increased from 1150 to 5240 mg/L at the digestion time of 5 d, while the maximal production of volatile fatty acids (VFA) increased from 82.6 to 183.9 mg COD/g volatile suspended solids. Although further increase of AR addition decreased the concentrations of both soluble COD and VFA, their contents in these systems with AR addition at any concentration investigated were still higher than those in the blank, which resulted in higher methane yields in these systems. Mechanism studies revealed that pertinent addition of AR promoted solubilization, hydrolysis, and acidogenesis processes and did not affect methanogenesis significantly. It was found that varieties of enzymes and anaerobes in AR were primary reason for the enhancement of anaerobic digestion. Humic substances in AR benefited hydrolysis and acidogenesis but inhibited methanogenesis. The effect of heavy metals in AR on sludge anaerobic digestion was dosage dependent. Sludge anaerobic digestion was enhanced by appropriate amounts of heavy metals but inhibited by excessive amounts of heavy metals. The relative abundances of microorganisms responsible for sludge hydrolysis and acidogenesis were also observed to be improved in the system with AR addition, which was consistent with the performance of anaerobic digestion.