净水技术2025，Vol.44Issue(12)：47-54,74,9.DOI:10.15890/j.cnki.jsjs.2025.12.006
水厂生产废水回用的安全性评估及工艺优化
Safety Evaluation and Process Optimization of Reuse of Production Wastewater in WTP
摘要
Abstract
[Objective]The reuse of wastewater from water treatment plants not only conserves water resources and reduces pollutant discharge but also decreases chemical consumption and sludge treatment costs,contributing to low-carbon emission reduction and significant environmental benefits.However,due to the complex composition of pollutants in production wastewater,its reuse may pose potential water quality safety concerns.Therefore,research on the safe reuse of wastewater from water treatment plants and the optimization of process parameters is necessary.[Methods]This paper was based on operational experiment at a water treatment plant in southwest China and laboratory-scale tests.It compared water quality variations in different treatment units between conventional processes and homogenized recirculation,exploring the feasibility of wastewater reuse and optimizing its operational parameters.[Results]During wastewater recirculation,the sedimentation tank achieved a higher removal efficiency for turbidity and other conventional indicators compared to conditions without wastewater recirculation.Specifically,under recirculation conditions,the filtration process removed turbidity,permanganate index,dissolved organic carbon,and ammonia nitrogen at rates of 84%,11%,4.6%,and 4.8%,respectively,while the sedimentation process achieved removal rates of 31%,22%,11.2%,and 48.4%,respectively.The contributions of different treatment processes to turbidity,ammonia nitrogen,permanganate index,and dissolved organic carbon removal followed the order of filtration＞sedimentation.The concentrations of metals such as aluminum,manganese,copper,zinc,arsenic,and lead in the finished water(60.77,9.70,22.78,16.10,12.70,11.51 μg/L)were higher than those without wastewater recirculation(3.80,0.65,6.73,0.66,5.75,1.37 μg/L).Based on orthogonal experiments,the optimal operational parameters for wastewater reuse included a sludge water recirculation ratio of 3%,a PAC dosage of 16 mg/L,and a sand filter backwash water recirculation ratio of 6%.[Conclusion]The recirculation of production wastewater enhances the coagulation and sedimentation process;however,it leads to the accumulation of metal elements.Nevertheless,the effluent quality of the water treatment plant generally complies with the Standards for Drinking Water Quality(GB 5749-2022).Under optimal operating conditions,the reuse of production wastewater reduces coagulant dosage by more than 5 mg/L,achieving a savings rate of over 30%.Therefore,the reuse of wastewater in water treatment plants not only ensures water quality safety and reliability but also aligns with clean production and low-carbon emission reduction policies,demonstrating both theoretical significance and practical application value.关键词
水厂/生产性试验/废水回用/强化混凝/最佳回流比Key words
water treatment plant(WTP)/production experiment/wastewater reuse/enhanced coagulation/optimal recirculation ratio分类
建筑与水利引用本文复制引用
LU Yonghui,LI Weiying,ZHANG Chen,JIANG Xiaolong..水厂生产废水回用的安全性评估及工艺优化[J].净水技术,2025,44(12):47-54,74,9.基金项目
国家自然科学基金(52470012) （52470012）
校企合作项目(kh0040020250130) （kh0040020250130）
