REMOVAL METHOD FOR NITRATE NITROGEN IN WATER AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a removal method for nitrate nitrogen in water due to a biological membrane method which enables the efficient removal of nitrate nitrogen in water to be treated at a relatively low cost by simple operation by adjusting the thickness of a liquid diffusion layer on the organism film of a rotary blade to keep the flow of water to be treated in a tank, and a removal apparatus using the same.

SOLUTION: This removal apparatus 2 for nitrate nitrogen in water is constituted so that a rotary shaft 7 is inserted in a tank having an introducing port 6 for water to be treated and a treated water discharge port 5 respectively provided to the lower and upper parts thereof and one or more blade members are provided to the rotary shaft so as to extend in a radial direction and the upper ends of the blade members are positioned under the opening part of the treated water discharge port. By this constitution of the removal apparatus, the moving speed of nitrate nitrogen on the surface of a biological membrane can be increased and the concentration of nitrate nitrogen of 10 mg/L or less regulated in Europe can be achieved in a relatively short time. Further, if the rotary blades are made small-sized, a small-sized denitrification treatment apparatus for nitrate nitrogen large in nitrate load capacity can be provided.

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