Abstract:
To enhance the dewaterability of anaerobic digested sludge and to make full use of the biogas slurry. This study set up five sludge conditioning methods: polymeric ferric sulfate, polymeric aluminum chloride, cationic polyacrylamide, chitosan, and chitosan combined with rice husk powder. Their effects on the dewaterability of thermal hydrolysis-anaerobic digested sludge, bacterial community, and biogas slurry fertility were studied to find a non-toxic and non-risk dewatering technology for the environment and biogas slurry. Compared with that of the control group, moisture content, normalization capillary suction time, and specific resistance to filtration were reduced by 12.8%, 97.7%, and 82.9%, respectively. Chitosan enlarges the sludge flocs and forms complexes with proteins, disrupting the structure of the extracellular polymeric substances, thereby exposing more hydrophobic groups and reducing the hydrophilicity of the sludge. The subsequent addition of rice husk powder enhances the adsorption of hydrophilic substances and provides a stronger drainage channel for the sludge. In addition, the biogas slurry obtained by this conditioning method used as a fertilizer increased the dry weight and fresh weight of corn seedlings by 59.3% and 91.0%, respectively. And the total chlorophyll content increased by 84.6%. Pearson\'s correlation analysis showed that chitosan and rice husk meal had no toxic effect on the biogas slurry compared to the other three flocculants. The results showed that the combined treatment of chitosan and rice husk powder resulted in the best dewaterability. Overall, chitosan combined with rice husk powder is a green dewatering technology with great potential for anaerobic digested sludge dewatering and biogas slurry recycling.
摘要:
增强厌氧消化污泥的脱水能力,充分利用沼液。本研究建立了五种污泥调理方法:聚合硫酸铁,聚合氯化铝,阳离子聚丙烯酰胺,壳聚糖,和壳聚糖结合稻壳粉。它们对热水解厌氧消化污泥脱水性能的影响,细菌群落,和沼液肥力进行了研究,以找到一种对环境和沼液无毒,无风险的脱水技术。与对照组相比,水分含量,正常化毛细管抽吸时间,过滤比阻力降低了12.8%,97.7%,和82.9%,分别。壳聚糖扩大污泥絮凝物,并与蛋白质形成复合物,破坏胞外聚合物的结构,从而暴露更多的疏水基团并降低污泥的亲水性。后续添加稻壳粉增强了亲水性物质的吸附,为污泥提供了更强的排水通道。此外,通过这种调理方法获得的沼液用作肥料,使玉米幼苗的干重和鲜重分别增加了59.3%和91.0%,分别。总叶绿素含量增加了84.6%。Pearson相关分析表明,与其他3种絮凝剂相比,壳聚糖和稻壳粉对沼液没有毒性作用。结果表明,壳聚糖和稻壳粉联合处理的脱水性能最好。总的来说,壳聚糖与稻壳粉结合是一种绿色脱水技术,在厌氧消化污泥脱水和沼液回收利用方面具有巨大潜力。