Closed purification method for rivers, lakes, ponds, and oceans

摘要

To provide a purification method capable of dredging sludge sedimented and adhered on a bottom surface of a river, lake, pond, etc., in a highly efficient and safe manner and at a low cost, without causing contamination to a larger water area and losing sand and soil.SOLUTION: A purification method comprises: a step 1 of submerging a cylindrical body for partitioning composed of a resin sheet cylindrical body having openings on an upper surface side and a lower surface side, a float fixed on an upper end edge of the cylindrical body and a plumb bob fixed on a lower end edge of the cylindrical body underwater from above in an area where sludge layers are accumulated, and causing its lower end to penetrate into the sludge layer; a step 2a of pump-pressurizing mixed water obtained by stirring and mixing a biodegradable magnetic flocculant in water in the cylindrical body for partitioning and jetting it to a bottom surface and dispersing the sludge layer in the water by excavating and separating it using injection water; a step 2b of stirring and mixing the water containing the dispersed sludge and the injected mixed water, and stirring and mixing the biodegradable magnetic flocculant in the mixed water; a step 3 of coagulating the sludge; a step 4 of carrying out a coagulated material such as sludge coagulated by a magnetic transportation device from the cylindrical body for partitioning to the outside; and a step 5 of shifting the cylindrical body for partitioning over an adjacent area.SELECTED DRAWING: Figure 1