Examination on Process Configurations Incorporating Thermal Treatment for Anaerobic Digestion of Sewage Sludge
Examination on Process Configurations Incorporating Thermal Treatment for Anaerobic Digestion of Sewage Sludge
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DOI：
10.1061/(asce)0733-9372(2008)134:7(543
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发表时间：
2008-07
影响因子：
2.2
通讯作者：
M. Takashima
中科院分区：
文献类型：
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作者：
M. Takashima
本研究旨在考察中温厌氧消化城市污泥的工艺配置，在120℃热处理1h的条件下，设计了4种工艺配置：对照(不进行热处理)、单级工艺的前处理和后处理配置、以及两级工艺的级间处理配置。实验室规模的消化器在35℃下运行，污泥的总固体含量为4.5%，总水力停留时间为20天。在稳态条件下，对照消化池的挥发性固形物(VS)损失率为35.3%，产甲烷量为0.168 L/g。与对照相比，前置、后置和间置处理的VS破坏分别增加4.5%、6.6%和9.9%，而后置和间置处理的甲烷产量分别提高0.036和0.028 L/g饲料。预处理配置产生了与对照相同的甲烷产量。因此，污泥一次消化后再进行中温处理对提高厌氧消化率更为有效。另一方面，随着固体破坏程度的提高，可溶化学需氧量增加，脱水性能恶化。
This study aimed to examine the process configurations for mesophilic anaerobic digestion of sewage sludge, when incorporated with thermal treatment of 120°C for 1 h. Four types of process configurations were designed: control (no thermal treatment), pretreatment and posttreatment configurations of the single-stage process, and an interstage-treatment configuration of the two-stage process. The lab-scale digesters were operated at 35°C with the sewage sludge of 4.5% total solids, and were equally set at the total hydraulic retention time of 20 days. At the steady state, the control digester showed 35.3% of volatile solids (VS) destruction and 0.168 L/g VS fed of methane production. Compared to the control, the VS destruction in the pre-, post-, and interstage-treatment configurations was increased by 4.5, 6.6, and 9.9%, respectively, while the methane production in the post- and interstage-treatment configurations was improved by 0.036 and 0.028 L/g VS fed, respectively. The pretreatment configuration yielded identical methane production to the control. Therefore, it is more effective on anaerobic digestibility to apply the moderate thermal treatment after sewage sludge is digested once. On the other hand, the increase in soluble chemical oxygen demand and deterioration of dewaterability were observed, when solids destruction was improved.