O_3-BAF深度处理制革废水中沿程污染物降解规律

Study on the Pollutants Removal Performance Along the Advanced Treatment in Tannery Wastewater by O_3-BAF

针对浙江省某制革园区污水处理厂二级生化出水,开展了处理规模36 t.d-1的臭氧-曝气生物滤池中试研究,考察了不同填料曝气生物滤池沿程高度上污染物的降解规律.结果表明:活性炭曝气生物滤池在沿程1 500 mm处的平均出水COD和色度分别为55.4 mg·L-1和12.6倍,混合填料曝气生物滤池在沿程1 800 mm处的平均出水COD和色度分别为55.6 mg·L-1和9.4倍,出水达到《城镇污水厂污染物排放标准》(GB 18918-2002)中的一级B排放要求.陶粒曝气生物滤池在整个沿程高度上COD和色度变化幅度较小.在沿程高度上活性炭曝气生物滤池和混合填料曝气生物滤池的COD和氨氮在1 200 mm内降幅较大,之后降幅趋缓.3个曝气生物滤池的生物量在沿程900 mm时达到最大,分别为30.69、28.87和15.94 nmol·g-1.

A pilot-scale hybrid process of ozone and biological aerated filters （BAF） with the capacity of 36 t＇d-1 was applied for advanced treatment of the secondary biologically effluent from a dyeing and tannery park wastewater treatment plant. The pollutants removal performance along the height of different medias BAFs were investigated. The results showed that the average COD and color were 55.4 mg.L-1 and 12.6 times at the height of 1 500 mm in activated carbon BAF, and were 55.6 mg＇L-1 and 9.4 times at the height of 1 800 mm in composite BAF, both of the effluent at each height met the first level B criteria specified in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant （GB 18918-2002）. Along the height of ceramist BAF, the COD and color were seldom removed. In activated carbon BAF and composite BAF, COD and ammonia nitrogen were both greatly decreased at the height of 1 200 mm, then decreased slowly. The biomasses simultaneously reached the maximum at the height of 900 mm in activated carbon, composite and ceramist BAF, with the maxims of 30.69, 28.87 and 15.94 nmol.g-1, respectively.