好氧颗粒污泥处理低碳氮比废水的运行参数优化

Optimization of Operational Parameters of Aerobic Granular Sludge for Treating Wastewater with Low Carbon to Nitrogen Ratio

研究了好氧颗粒污泥(AGS)处理低碳氮比(C/N为3和1)废水的脱氮性能,通过单因素试验探究了污泥浓度、碳源投量、自养AGS占比及碱度对总无机氮(TIN)去除率的影响,以确定各影响因素适宜的范围;利用响应曲面法分析各因素对TIN去除率的影响,以确定最佳运行工况。当进水C/N为3时,显著性影响因子排序为:污泥浓度>碳源投量>自养AGS占比>碱度;当进水C/N为1时,显著性影响因子排序为:碳源投量>污泥浓度>自养AGS占比>碱度。当C/N为3时,最佳工况参数如下:污泥浓度为6260.32 mg/L、碱度为556 mg/L、自养AGS占比为39.96%、碳源投量为165.61 mg/L,预测AGS对TIN的去除率为94.61%;参考德国ATV标准(ATV-DVWKA131E)推荐的碳源投量,在最佳工况下可节省17.2%的外投碳源、22.1%的碱度及16.7%的能耗。当C/N为1时,最佳工况参数如下:污泥浓度为5172.11 mg/L、碱度为1166 mg/L、自养AGS占比为21.88%、碳源投量为857.43 mg/L,预测TIN去除率为56.95%。

This paper investigated the nitrogen removal performance of aerobic granular sludge(AGS)for treating the wastewater with low carbon to nitrogen ratio(C/N ratio of 3 and 1).The effects of sludge concentration,carbon source dosage,autotrophic AGS proportion and alkalinity on the removal rate of total inorganic nitrogen(TIN)were explored by single factor experiments,and then the approximate range of each influencing factor was determined.The influence of each factor on TIN removal rate was analyzed by using the response surface method,and the best operating parameters were eventually determined.When the influent C/N ratio was 3,the significant of influencing factors in descending order was as follows:sludge concentration,carbon source dosage,autotrophic AGS proportion and alkalinity,and that was carbon source dosage,sludge concentration,autotrophic AGS proportion and alkalinity when the influent C/N ratio was 1.When the influent C/N ratio was 3,the optimal operating parameters for nitrogen removal were as follows:sludge concentration of 6260.32 mg/L,alkalinity of 556 mg/L,autotrophic AGS proportion of 39.96%and carbon source dosage of 165.61 mg/L,and the predicted TIN removal rate was 94.61%.According to the carbon source dosage recommended by the German ATV standard(ATV-DVWKA131E),17.2%of carbon source dosage,22.1%of alkalinity and 16.7%of energy consumption were saved under the optimal operating conditions in this study.When the influent C/N ratio was 1,the optimal operating parameters were as follows:sludge concentration of 5172.11 mg/L,alkalinity of 1166 mg/L,autotrophic AGS proportion of 21.88%and carbon source dosage of 857.43 mg/L,and the predicted TIN removal rate was 56.95%.