DEVICE FOR REMOVING CONTAMINATED SAND IN OXIDATION DITCH

摘要

PURPOSE:To efficiently collect the contaminated sand contained in the sewage flowing into an oxidation ditch. CONSTITUTION:A screw aerator is provided in the oxidation ditch of requisite shape having a circulating water passage, and a contaminated sand collecting pit 4 is furnished below the screw 3S of the aerator. Discharge means 5 and 6 are provided in the pit 4 to discharge the contaminated sand collected in the pit 4, and the contaminated sand flowing together with the sewage is discharged outside the ditch. Consequently, the contaminated sand is collected in the pit 4 by utilizing the flow characteristic of the aerator, and efficiently discharged outside the system through the discharge pipeline 6.