微絮凝砂滤-臭氧催化氧化强化石化生化出水COD去除

为强化石化生化出水COD的去除，采用微絮凝砂滤-臭氧催化氧化工艺处理石化生化出水，比较了臭氧催化氧化反应器不同氧化方式和不同回流比组合方式下COD的去除，开展了臭氧催化氧化深度处理单元小试、中试和生产性规模研究，确立了以双级臭氧催化氧化Ⅰ级自回流工艺（回流比100%）为双级臭氧催化氧化推荐的优化工艺。生化出水ρ（COD）为70~120 mg/L时，微絮凝砂滤出水ρ（COD）达到65~113 mg/L，Ⅱ级氧化出水COD平均去除率达到35.0%~42.6%，出水满足GB 31571-2015《石油化学工业污染物排放标准》排放限值要求。生产性试验条件下，优化工艺装置去除单位COD消耗臭氧量平均为1.04 g/g，比对照组现阶段生产工艺（仅Ⅰ级臭氧曝气）降低了21.2%。

MICRO FLOCCULATING SAND FILTER-CATALYTIC OZONATION ENHANCED COD REMOVAL FROM BIO-TREATED PETROCHEMICAL WASTEWATER

In order to enhance the COD removal of petrochemical biochemical effluent, the removal effect of micro flocculation sand filtration and ozone catalytic oxidation on COD in petrochemical biochemical effluent was analyzed. The COD removal under different combination modes of ozone catalytic oxidation tower was compared. The lab-scale, pilot-scale and productive scale of catalytic ozonation were carried out. The ozonation tower with two stages, one-stage aeration and one-stage reflux (reflux ratio 100%) were recommended for its good performance. When the bio-treated petrochemical wastewater was 70~120 mg/L, micro flocculating sand filter effluent was 65~113 mg/L, the remocal rate of COD in two-stage effluent reached 35.0%~42.6%, meeting the emission standard for petroleum chemical industry(GB 31571-2015). Compared with the one stage aeration process production test device, ozone consumption for per unit COD of the selected optimized technology was 1.04 g/g and reduced by 21.2% comparing with the original process (single stage ozonation).