Tertiary nitrification in a new dual-medium aerated filter

摘要

In an effort to develop an aerated filter with high nitrification capabilities, we formulated a new filter with 2 layers: the upper layer is filled with a plastic medium, and the lower with anthracite. We tested the filter in a pilot-scale apparatus on secondary-treated sewage, and in a small-scale apparatus on secondary-treated sewage and on artificial sewage. We evaluated the nitrification characteristics under various conditions of water velocity, air velocity, temperature, and pH. We designed a tertiary plant to treat 20,000 m(3)/day of secondary-treated sewage, using the new filter or a conventional filter. From these comparisons, it appeared that the dual-medium aerated filter had high nitrification capabilities and was an effective device for tertiary sewage treatment. [References: 9]