Fe3O4对厌氧处理系统的强化作用研究

Study on performance of anaerobic treatment system enhanced by Fe3O4

投加Fe3O4能够在一定程度上强化有机物的厌氧降解过程,而进水有机负荷是影响厌氧系统处理效率的重要因素.本研究通过分阶段提升进水有机负荷,对比考察了Fe3O4的加入对UASB厌氧反应器运行效能及污泥性质的影响.结果表明,当有机负荷低于3.2 kg·m^-3·d^-1时,两反应器内有机物厌氧水解效率并无显著性差别.而当有机负荷提升至6.4、12.8、25.6 kg·m^-3·d^-1时,Fe3O4对有机物厌氧水解效率表现出一定的促进效果,且有机负荷越高,Fe3O4对厌氧水解的促进效果越显著.与此同时,Fe3O4对厌氧产甲烷过程也表现出明显的促进作用,在有机负荷分别为1.6、3.2、6.4、12.8、25.6 kg·m^-3·d^-1时,添加Fe3O4的反应器中平均甲烷产率分别为对照组的3.55、2.37、1.26、1.16和1.06倍.这一现象表明Fe3O4对产甲烷过程的促进效果与有机负荷密切相关,且有机负荷越低,Fe3O4对厌氧产甲烷效率的增强作用越明显.此外,本研究还分析了运行过程中污泥粒径和胞外聚合物的变化,发现Fe3O4的加入可以有效促进厌氧污泥颗粒化进程.

The addition of Fe3O4 can enhance the anaerobic degradation process of organic pollutants,the influent organic loading rate(OLR)is an important factor affecting the treatment efficiency of anaerobic system.In current research,we investigated and contrasted the influence of Fe3O4 addition on UASB operational performance and sludge property by stepwise elevating the OLR in influent.The results showed that at the OLR of lower than 3.2 kg·m^-3·d^-1,no significant distinction of hydrolysis efficiency was observed between two reactors.Nevertheless,when the OLR was elevated to 6.4,12.8 and 25.6 kg·m^-3·d^-1,the hydrolysis efficiency could be definitely improved by the addition of Fe3O4,and the improvement was more remarkable at higher OLR operation.Meanwhile,Fe3O4 also showed obvious promotion to methanogenesis process.At the OLR of 1.6,3.2,6.4,12.8,25.6 kg·m^-3·d^-1,the average methane production rate in the reactor with Fe3O4 was 3.55,2.37,1.26,1.16 and 1.06 times than the control reactor.This phenomenon demonstrated that the enhancement of Fe3O4 on the methane producing rate was closely related with organic load,and the lower the organic load,the more obvious the enhancement effect of Fe3O4 on anaerobic methanogenic efficiency.In addition,the study also analyzed the changes of sludge particle size and extracellular polymer during the operation process.It was found that the addition of Fe3O4 could effectively accelerate the sludge granulating process.