针铁矿促进剩余污泥厌氧消化中的脱氮除碳

剩余污泥厌氧消化因其较低的能源转化率使其发展有所受限，且污泥中高浓度有机质也会影响脱氮效果。理论上，在含铁(Ⅲ)（氢）氧化物的厌氧消化系统中，微生物能通过异化铁还原去除有机物和氨氮（Feammox），但两者同步去除还有待验证。因此本研究通过向污泥厌氧消化系统中添加针铁矿，探究铁(Ⅲ)（氢）氧化物对同步脱氮除碳的影响。结果显示，随着针铁矿添加量的增加，反应器中有机物浓度逐渐减少。当添加50mmol/L针铁矿时，甲烷累积产量达到695.1mL，相较于没有添加针铁矿的厌氧系统提升了30.3%;TS/VS去除率也提升了21.1%/33.8%，说明针铁矿可有效促进污泥减量化。添加针铁矿的反应器中总氮去除率也有一定提升，当针铁矿添加50mmol/L时，去除率达到21.0%。以上结果表明，添加针铁矿可以在污泥厌氧消化中起到同时脱氮除碳的效果。

Goethite promotes the removal of nitrogen and carbon in the anaerobic digestion of waste activated sludge

The development of anaerobic digestion of waste activated sludge (WAS) is limited due to its low energy conversion rate, and the high concentration of organic matter in the sludge also inhibits nitrogen removal. Theoretically, organic matter and ammonium could be removed through dissimilatory iron reduction in an anaerobic digestion system containing Fe(Ⅲ) (hydr) oxides, which however remains to be verified. Therefore, in this study goethite was added to the sludge anaerobic digestion system to explore the effect of Fe(Ⅲ) (hydr) oxide on the simultaneous removal of carbon and nitrogen. The results showed that with the increase of goethite dosage, the concentration of organic matter in the reactor gradually decreased. The cumulative methane production reached 695.1mL when 50mmol/L goethite was added, which was 30.3% higher than that of the control group without goethite. The TS and VS removal rates of the 50mmol/L goethite-added group were also increased by 21.1% and 33.8%, respectively, demonstrating that goethite could accelerate sludge reduction. Goethite also promoted the removal of total nitrogen and the removal efficiency was 21.0% in 50mmol/L goethite-added reactor. The above results showed that goethite can remove nitrogen and carbon simultaneously in sludge anaerobic digestion.