粒子群电解法降解焦化废水中酚的影响因素研究

Influencing Factors for Phenol- containing Coking Wastewater Treatment Using Particle Electrolysis

通过粒子群电解装置(PEC)对含酚废水进行处理,对影响粒子群的一些基本因素(电解时间、pH值、电流、电压、添加剂和不同填充粒子)进行了试验分析,得出了最佳的操作参数;同时也对PEC装置处理煤制气厂的焦化含酚废水进行了试验验证,为实际进行工业应用提供了可靠依据;还探讨了粒子群电解法降解有机污染物的主要机理。

Phenol and its derivatives are widely used as raw materials in many chemical and pharmaceutical, petrochemical industries and related industries. The aqueous effluents from these industries containing phenolic compounds are toxic and cause considerable damage and threat to the ecosystem in water bodies and human health. Therefore the removal of phenol wastewater is of environmental interest. In this paper, Degradation of phenol in artificial wastewater containing phenol with the concentration of 1 603.5 mg· L- 1 was investigated in a cell with SnO2 electrodes using different fillings as particle electrodes. This reactor designed was comprised of SnO2 film electrode as the anode together with stainless steel plate as the cathode and fillings. SnO2 film electrodes were prepared by the standard spray hydrolysis method and different fillings were packed between the two electrodes as particle electrode. The influencing factors of the reactor in treating phenolic wastewater in the sequent batch runs were researched. The results showed that this reactor could remove phenol much more efficiently than conventional three- dimensional electrode did. Furthermore, the phenol removal efficiency depended on the electrolysis time, pH values, the cell voltage, solution conductivity and the number of repeated electrolyses. When using GAC (granular activated carbon) as the fillings, the phenol removal efficiency could reach as high as 86% . The most favorable parameters were: electrolysis voltage 12 V, current 0.24 A, reaction time 30 min, pH ranged from 3 to 5, the concentration of sodium chloride, as the effective additional reagent, being 0.3% of wastewater. The reactor maintained more than 86% phenol removal efficiency after 60 runs. Effects of SiO2 sand or MnO2 sand as particle electrodes packed between the two main electrodes on phenol treatment (with the phenol reduction 70% and 83% , respectively) were also studied. The removal results were satisfied when using the reactor in treating the true phenol- containing coking wastewater from a gasworks, and we concluded that particle electrodes reactor could efficiently degrade phenol wastewater and might be a feasible and safe alternative process for the toxic organic wastewater treatment.