摘要
为减少重金属污染,以猪粪为发酵原料,采用厌氧发酵技术进行试验。结果表明:添加沸石对沼气发酵产气量、甲烷含量影响不大;厌氧发酵后,添加沸石组重金属Zn的89.88%存在于沼渣中,10.12%存在于沼液中;Zn总量下降了32.41%,下降幅度高于空白对照组;厌氧发酵后,沼渣、沼液中的重金属形态都以残渣态为主,添加沸石组的沼渣、沼液中残渣态的比例高于空白对照组;厌氧发酵后,空白组沼渣中重金属Zn的有效态含量占32.63%,添加沸石组重金属Zn的有效态含量占29.12%。添加沸石有利于降低重金属Zn的生物有效性,因此,建议在厌氧发酵过程中添加重金属钝化剂,以此减少沼肥回田后重金属污染的风险。
The research is aimed at reducing the heavy metals pollution, so in this experiment takes pig manure as fermentation raw materials, adopting anaerobic fermentation technology to study the effects of adding exogenous zeolite on biogas production, methane content and the change of the proportion and chemical fractions of heavy metal Zinc in digestate. The results show that： Zeolite has no significant effects on gas production and methane content in biogas fermentation. After anaerobic fermentation, two groups of test of heavy metal Zinc are falling totally, adding zeolite group falls32.41%, the falling rate is higher than that of the contrast group. After fermentation in adding zeolite group 89.88% of heavy metals Zinc exists in biogas sludge, only 10.12% in biogas slurry. And in the contrast group, 94.53 % in biogas sludge, 5.47% in biogas slurry. After anaerobic fermentation of pig manure, fraction of heavy metal Zinc exists priority in the form of residual fraction, whether in biogas sludge or in biogas slurry. The heavy metal Zinc residual fraction of biogas fertilizer in adding zeolite group is higher than that in the contrast group. After anaerobic fermentation, heavy metal Zinc content in the biogas sludge is more than that in the biogas slurry, effective fraction of heavy metal Zinc content in the contrast group biogas sludge accounts for 32.63%, which is 29.12% in adding zeolite group, furthermore, the effective fraction of biogas slurry in adding zeolite group is also lower than that of the contrast group. Thus it suggests that metal passivator is added to the anaerobic fermentation process so as to reduce the risk of heavy metals pollution after biogas fertilizer is back to the field as feitilizer.
出处
《可再生能源》
CAS
北大核心
2016年第6期943-948,共6页
Renewable Energy Resources
基金
国家自然科学基金青年科学基金项目(31400442)
辽宁省自然基金面上项目(2015020635)
关键词
猪粪
厌氧发酵
沸石
重金属锌
含量
形态
pig manure
anaerobic fermentation
zeolite
heavy metals zinc
content
fraction
