基于沼渣的生物炭负载零价铁强化牛粪厌氧产甲烷研究

针对养殖场废物厌氧消化处理中存在的沼气产量较低和沼渣资源化利用较低等不足,文章以沼渣为原材料,通过铁盐改性制备获得生物炭(biochar,BC)负载零价铁(zero-valent iron,ZVI)复合材料(ZVI-BC),并将其用于强化牛粪的厌氧产甲烷过程。研究结果表明:ZVI-BC具有更丰富的官能团种类、更大的比表面积和孔隙率;添加ZVI-BC对牛粪厌氧消化过程有一定促进作用,产气量较对照组提高3.35%~26.87%,甲烷体积分数提高7.01%~16.22%;低添加量的ZVI-BC对甲烷的促进作用更加显著;添加ZVI-BC有助于缓解有机酸积累、吸附中间有毒有害产物及增加消化体系缓冲能力。研究结果可为养殖场废物厌氧处理的研究和应用提供参考。

Aiming at the shortcomings of low biogas production and low resource utilization of biogas residue in anaerobic digestion treatment of farm waste, this paper prepared biochar (BC) supported zero-valent iron (ZVI) composite material by modifying biogas residue with ferric salt (ZVI-BC) to enhance the anaerobic digestion efficiency of cow manure. The results showed that ZVI-BC has more functional group types, larger specific surface area and porosity. The addition of ZVI-BC has a certain promotion effect on the anaerobic digestion of cow manure. Compared with the control, the gas production and methane volume fraction were increased by 3.35%-26.87% and 7.01%-16.22%, respectively. Low-added ZVI-BC has a more significant promotion effect on methane, which plays an important role in alleviating the accumulation of organic acids, adsorbing the intermediate toxic and harmful products, and increasing the buffering capacity of the system. The research results can provide reference for the study and application of anaerobic treatment of farm waste.