PREVENTION OF WATER POLLUTION OF MEDIUM AND SMALL-SIZE RIVER

摘要

PURPOSE:To prevent the water pollution of river by promoting the clarification action of pollutants in river water by means of microorganisms by a method in which a circulation waterway is formed in a medium- or small-size river in a flat area, and a water-pumping device is set in the circulation waterway so as to form a forced circulating water flow. CONSTITUTION:A waterway J serving as a sedimentation basin is formed by excavating the area between the upstream end of one F of existing waterways A-I and a waterway C, and water gates 11, 12, and 13, an overflow sluice 2 and wate-pumping sluices 31, 32, and 33 are provided. When operating water- pumping devices provided at the water pumping sluices 31, 32, and 33 of each circulation waterway, consisting of waterways EBAD, FBGCJ, and HBIC, the water in the waterways flows circularly in the direction of arrow, where pollutants in the water are biologically treated under aerobic condition and floating solids settle in the basins D and J. When the average flow rate in portions other than the sedimentation basin of the circulation waterways is set to about 0.01- 1.0m/sec, the water pollution of the waterways can be most effectively prevented.