不同基质条件对亚硝化污泥胞外聚合物的影响

Effect of substrate concentration and type on the content of extracellular polymeric substances in the nitrification sludge

摘要:

为研究基质质量浓度和类型对污泥中胞外聚合物(EPS)质量分数的影响,采用6个SBR反应器以不同氨氮质量浓度和不同基质为进水对比污泥中EPS质量分数．结果表明:氨氮质量浓度为60～200 mg／L时,EPS质量分数随氨氮质量浓度增大而增加,氨氮质量浓度超过200 mg／L时,EPS质量分数无明显增加;多糖与蛋白质的比与氨氮质量浓度线性相关,R²为0.972 3;污泥中EPS组分受基质类型的影响,以葡萄糖为基质的污泥EPS组分中多糖质量分数偏高,以生活污水为基质的污泥EPS组分中蛋白质质量分数偏高;EPS中的蛋白质和多糖具有可降解性,当基质缺乏时可作为碳源、能源被微生物消耗;EPS影响污泥沉降性,随EPS质量分数增加,SVI呈逐渐减小趋势．

Abstract:

The content of EPS affects the characteristics of sludge and formation of the granular sludge.To study the effect of substrate concentration and type on the EPS content and the sludge settling performance, six SBR reactors with different ammonia concentrations and different substrates were used. The results showed that the EPS content increased with the increase of ammonia concentration only when ammonia nitrogen concentration was 60-200 mg／L, but did not increase significantly when the ammonia nitrogen concentration exceeded 200 mg／L. The relationship between the ratio of polysaccharide to protein and ammonia concentration was a linear correlation, with R² of 0.972 3. The EPS was influenced by the substrate type, higher content of polysaccharide with glucose as organic, and higher content of protein with domestic waste water as substrate. The protein and polysaccharide were biodegradable, which could be used by microorganisms as carbon source and energy when the substrate was deficient. The sludge sedimentation could be affected by the EPS content, and the SVI decreased with the increase of EPS content.