以广州某公司生产酚醛树脂时产生的酚醛废水为研究对象,针对其高浓度、生物毒性强、可生化性差及难降解等特点,设计缩聚-Fenton-A/O生物流化床联合工艺进行处理。此工艺的工程实践中,在总HRT低于75 h的操作条件下,当进水COD、苯酚及甲醛浓度分别为1.0×105~1.2×105 mg/L、2.2×104~2.5×104 mg/L及1 800~2 100 mg/L时,经缩聚、Fenton物化法预处理后,相应的去除率分别为(92.5±0.8)%、(98.6±0.2)%及(98.7±0.3)%,废水中有机物浓度及其毒性大为降低。将预处理后的酚醛废水和生活污水混合以提高生化性,再经自行研制的新型结构生物三相流化床A/O工艺及后续混凝高效处理,出水中COD、苯酚及甲醛浓度分别降至38~60 mg/L、0.1~0.2 mg/L及0.3~0.5 mg/L范围内。在正常运行工况条件下,工艺出水污染物指标均低于《广州市污水排放一级标准》(DB4437-90)的限值。工程实践证明,该组合工艺针对高浓度、高毒性的酚醛废水具有处理效果好、耐冲击负荷能力强以及管理费用低等特点,成为可以推广的实用技术。
A condensation-Fenton-A/O biological fluidized bed process was designed and applied to treat the phenolic wastewater with low bio-degradability,high concentration and toxicity from a phenolic resin plant in Guangzhou.When the total HRT was less than 75 h,and the initial concentrations of COD,phenol and formaldehyde in the influent were 1.0×105~1.2×105 mg/L,2.2×104~2.5×104 mg/L and 1 800~2 100 mg/L,respectively,(92.5±0.8)%,(98.6±0.2)% and(98.7±0.3)% of COD,phenol and formaldehyde were removed after the condensation-Fenton pretreatment.The effluent was mixed with domestic sewage to improve its biodegradability.Then the mixture was treated by an A/O biological three phase fluidized bed process and coagulation.The concentrations of the COD,phenol and formaldehyde in the effluent decreased to 38~60 mg/L,0.1~0.2 mg/L and 0.3~0.5 mg/L,respectively.Under normal operating conditions,the pollutant concentrations in the effluent could meet the First-Order of Guangzhou City Sewage Discharging(DB4437-90).The results showed that the combined process exhibited some advantages such as good effect,high loading capacity and resistance to shock and low manage cost,enabling a promising practical technology.