核桃壳-沸石曝气生物滤池处理含铬有机废水的研究

Research on chromate organic wastewater treatment by biological aerated filter using walnut shell-zeolite

利用自制核桃壳-沸石曝气生物滤池（BAF）处理制革复鞣含铬有机废水，考察了水力负荷对Cr（Ⅲ）和化学需氧量（COD）的影响，并通过脂磷法和电镜扫描分别测试和观察反应器的生物量和微生物的分布状况。结果表明：核桃壳-沸石BAF去除含铬有机废水的最佳运行参数为：水力负荷0．02m／h。水力停留时间（HRT）24h时，Cr（Ⅲ）去除率可达95．42％，COD去除率可达94．74％。BAF取样口2号和3号为去除Cr（Ⅲ）的高效段。由填料的电镜扫描照片可知：BAF有着明显的生物分层效果，在取样口2和3号生物种类较为丰富，该段主要依靠好氧微生物的生物氧化和生物吸附机制去除Cr（Ⅲ）和COD等指标。

The organic wastewater containing chromium in retanning process was treated by self-made biological aeration filter （BAF） using walnut shell and zeolite as the media. The influence of hydraulic load in Cr（Ⅲ） and chemical oxygen demand （COD） were investigated and the lipid-P method was used to measure the content of biomass and scanning electron microscopy was used to investigate the distribution of microorganism on the reactor. The results show that optimal hydraulic load is 0. 02m/h, hydraulic retention time （HRT） is 24h, the removal rate of Cr （Ⅲ ） is up to 95.42%, the removal rate of COD is up to 94. 74%. The most efficient phase Cr（Ⅲ） removal of BAF are the number 2 andnumber 3 sampling ports. The picture of electron microscope scanning of media shows that reactor has obvious biological layer, the number 2 and number 3 sampling ports have abundant species and are mainly rely on the aerobic biological oxidation and biological adsorption mechanism of microorganism to remove Cr （Ⅲ）, COD and other indexes.