Hui-Ping Zeng
Beijing University of Technology, China
Title: The evolution of the bio-filter layer for Manganese removal and the countermeasure
Biography
Biography: Hui-Ping Zeng
Abstract
Biological filtration is the highly-efficient and economical process for manganese removal from groundwater, but after the bio-filter's long time operation manganese concentration of the effluent often exceeded the PRC national standards for drinking water quality. In order to know the truth, the as-prepared samples of the filter media were characterized. The filtration experiment had been done using filter media in various properties from mature bio-filters which had run for different time: just maturation, after 2 years operation. Also we replaced the old sand in the bio-filter with the new sand in different proportion (50%, 30%, 25%, 15%, 10%) to investigate the filtration effect. The results indicated that the diameter of the filter media became more and more lager due to the adhesion and accumulation of oxides of iron and manganese after long time operation, which led to the change of filter bed structure and even the deterioration of filtrate. Therefore, to maintain high efficiency of manganese removal in long-term operation, replacing some old filter media which optimum thickness was 10cm to 15cm with new one periodically was necessary and feasible.