微纳米气泡共混凝工艺下多因素交互作用

Interactions of multiple factors in micro-nano bubbles coagulation process as explored with Response surface methodology

为强化微纳米气泡共混凝工艺性能,本文以聚合氯化铝(PACl)、微纳米气泡进气量(Q_(g))以及溶液pH值为影响因素,以沉淀出水中腐殖酸(HA)去除效率和剩余Al^(3+)浓度为响应值,通过Box-Behnken设计(BBD)以及响应面法探究该工艺背景下各因素间的交互作用.实验结果表明,PACl投加量、Q_(g)以及pH值均能够显著影响该工艺对HA的去除效率.但对于沉淀出水中Al^(3+)浓度而言,PACl投加量以及Q_(g)均不会造成显著影响,pH值为该响应值的显著影响因素.与常规混凝工艺相比,混凝过程中微纳米气泡的参与能够显著降低沉淀出水中剩余Al^(3+)浓度,提高混凝过程中PACl的利用效率.对HA去除效率及剩余Al^(3+)浓度的综合评估结果表明,微纳米气泡共混凝工艺更适用于处理pH值为中性的原水.上述结论再次突出了微纳米气泡共混凝工艺的优越性,同时也为该工艺的工程应用提供了可靠的数据支撑和理论支持.

The micro-nano bubbles(MNBs)-coagulation process developed to meet the needs of cleaning production has attracted the public's attention,but the interactions between multiple factors in this process has not been fully understood.Box-Behnken design(BBD)and response surface methodology were used to explore interactions between factors in the MNBs-coagulation process by taking polymeric aluminium chloride(PACl),micro-nano bubbles intake(Qg),and solution pH as the influencing factors,and humic acid(HA)removal efficiency and the residual Al^(3+)concentration in the precipitated water as the response variables.The results show that the PACl dosage,Qg and pH could significantly affect the removal efficiency of HA,however,neither the PACl dosage nor the Qg had a significant effect on the Al^(3+)concentration in the precipitation effluent except pH’s significant influence on the response variable.Compared with the conventional coagulation process,the participation of MNBs in the coagulation process could significantly reduce the residual Al^(3+)concentration in the precipitated water and improve the utilization efficiency of PACl.Evidently,the MNBs-coagulation process is more suitable for treating pH-neutral raw water,and our study will provide reliable data and theoretical support for the engineering application of the MNBs-coagulation process.