污泥回流调控影响因素探究与模型预测  

Investigation and model prediction of factors influencing sludge reflux regulation

作　　者：李一鸣[1] 肖萍 王世杰[1] 王涛 程紫微 郭欣 李能能 肖峰 LI Yiming;XIAO Ping;WANG Shijie;WANG Tao;CHENG Ziwei;GUO Xin;LI Nengneng;XIAO Feng(North China Electric Power University,Beijing 102206,China;Green Intelligence Environmental School,Yangtze Normal University,Chongqing 408100,China;Ningxia Great Wall Water Co.,Ltd,Yinchuan 750004,China)

机构地区：[1]华北电力大学,北京102206 [2]长江师范学院绿色智慧环境学院,重庆408100 [3]宁夏长城水务有限责任公司,银川750004

出　　处：《环境工程学报》2023年第9期2958-2965,共8页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金重大项目(52030003)。

摘　　要：为了解影响污泥回流强化混凝效能的影响因素,以水洞沟水库水为研究对象,通过混凝实验模拟不同工况对沉后水质、有机物去除的影响,同时应用偏最小二乘法建立污泥回流比控制模型。结果表明,相较于未回流污泥的原水而言,混合水浊度控制在500~1000 NTU时,出水浊度最低约为1.2 NTU,CODMn小于1.5 mg·L^(−1),需要的药剂最少,为30 mg·L^(−1)。混合水浊度继续升高,混凝效果变差。温度升高有利于混凝反应的进行。相对于0~15℃而言,15~20℃时,出水浊度更低,约为1 NTU。出水CODMn小于1.5 mg·L^(−1),需要的药剂量最低,为20~25 mg·L^(−1)。此外,可调控的适宜混合水浊度范围较广。混凝效果随着SVI、MLSS的增大,呈现先降低后升高的趋势。当SVI为15~19 mL·g^(−1),混合水浊度控制在500 NTU时,混凝出水水质较好。当MLSS为55~70 g·L^(−1),混合水浊度控制在500~1500 NTU时,混凝出水水质较好。根据以上结果建立的回流比控制模型拟合效果较好(R2=0.778,RMSE=1.28),模型能较好地预测回流比变化趋势。本研究结果可为实际污泥回流工艺运行提供参考。To clarify the factors that influenced the effect of sludge reflux-enhanced coagulation,this study used the water of Shuidonggou Reservoir as the research.The effects of various working conditions on the postsedimentation water quality and organic matter removal were simulated by coagulation experiments,while the partial least squares method was applied to establish a control model for the sludge reflux ratio.The experimental results suggested that when the turbidity of the mixed water is controlled between 500 and 1000 NTU compared to the raw water without refluxed sludge,the turbidity of the effluent was about 1.2 NTU,the CODMn was less than 1.5 mg·L^(−1),while the minimum required coagulant was 30 mg·L·1.When the turbidity of the mixed water keeps rising,the coagulation effect becomes worse.Besides,the experiments also indicated that temperature rise was conducive to the coagulation reaction.Compared to 0~15℃,the lowest turbidity of the effluent was at 15~20℃,about 1 NTU.The effluent CODMn was less than 1.5 mg·L^(−1),and the minimum required coagulant was 20~25 mg·L^(−1).Furthermore,the turbidity range of suitable mixed water which can be adjusted was more wider.It was found that the coagulation effect showed a trend of decreasing first and then increasing with the increase of SVI and MLSS.When the SVI was between 15 and 19 mL·g^(−1),the mixed water turbidity was controlled in 500 NTU,the effluent quality was good after coagulation.When the MLSS was 55~70 g-L^(−1),the mixed water turbidity was controlled at 500~1500 NTU,the effluent quality was good after coagulation.The reflux ratio control model established based on the above results fitted well(R2=0.778,RMSE=1.28),and the model was able to predict the trend of reflux ratio better.The model can effectively predict the trend of reflux ratio changes.Therefore,the results of this study can provide useful reference data for the operation of the actual sludge reflux process.

关 键 词：混凝 混合水浊度 污泥质量浓度 污泥指数 偏最小二乘法 

分 类 号：X705[环境科学与工程—环境工程]