Abstract: A differential rate rotary thickener; a power detector which is disposed in a sludge receiver tank for thickened sludge thickened in the differential rate rotary thickener; a discriminator which receives an electric signal for a thickened sludge concentration detected by the power detector and which calculates and discriminate the data; a first controller which receives an instruction signal being a discriminated result in the discriminator and which operates an outer cylinder driving machine and a screw driving machine; a ratio setter which receives a discriminated signal of the discriminator and which increases or decreases a chemical feed rate of flocculant stepwise; and a second controller which receives an instruction signal from the ratio setter and which operates a flocculant-feeding pump are provided. Thickening of sludge is performed by controlling the chemical feed rate, a rotational speed of a screw, and a rotational speed of an outer cylinder screen.

Abstract: A differential rate rotary thickener; a power detector which is disposed in a sludge receiver tank for thickened sludge thickened in the differential rate rotary thickener; a discriminator which receives an electric signal for a thickened sludge concentration (X) detected by the power detector and which calculates and discriminate the data; a first controller which receives an instruction signal being a discriminated result in the discriminator and which operates an outer cylinder driving machine and a screw driving machine; a ratio setter which receives a discriminated signal of the discriminator and which increases or decreases a chemical feed rate (?) of flocculant stepwise; and a second controller which receives an instruction signal from the ratio setter and which operates a flocculant-feeding pump are provided. Thickening of sludge is performed by controlling the chemical feed rate (?), a rotational speed (S) of a screw, and a rotational speed (C) of an outer cylinder screen.

Abstract: [Solving Means] A differential rate rotary thickener; a power detector which is disposed in a sludge receiver tank for thickened sludge thickened in the differential rate rotary thickener; a discriminator which receives an electric signal for a thickened sludge concentration detected by the power detector and which calculates and discriminate the data; a first controller which receives an instruction signal being a discriminated result in the discriminator and which operates an outer cylinder driving machine and a screw driving machine; a ratio setter which receives a discriminated signal of the discriminator and which increases or decreases a chemical feed rate of flocculant stepwise; and a second controller which receives an instruction signal from the ratio setter and which operates a flocculant-feeding pump are provided. Thickening of sludge is performed by controlling the chemical feed rate, a rotational speed of a screw, and a rotational speed of an outer cylinder screen.

Abstract: A differential rate rotary thickener; a power detector which is disposed in a sludge receiver tank for thickened sludge thickened in the differential rate rotary thickener; a discriminator which receives an electric signal for a thickened sludge concentration (X) detected by the power detector and which calculates and discriminate the data; a first controller which receives an instruction signal being a discriminated result in the discriminator and which operates an outer cylinder driving machine and a screw driving machine; a ratio setter which receives a discriminated signal of the discriminator and which increases or decreases a chemical feed rate (?) of flocculant stepwise; and a second controller which receives an instruction signal from the ratio setter and which operates a flocculant-feeding pump are provided. Thickening of sludge is performed by controlling the chemical feed rate (?), a rotational speed (S) of a screw, and a rotational speed (C) of an outer cylinder screen.

Abstract: This invention relates to a filter cloth suspending apparatus in which a filter cake is produced by pressing sewage and waste water between filter cloths with filter plates, and the obtained cake is discharged. In the apparatus, an upper edge of the filter cloth (3) is supported on an upper supporting bar (13), on the other hand, a lower edge of the filter cloth is formed in a concave shape, and a suspending member (15) is connected to both corners (18, 20). Thus, the contact of the lower edge of the filter cloth with the upper supporting bar is prevented, and damage of the filter cloth is prevented. Further, sagging of the lower edge of the filter cloth is also prevented.

Abstract: A filter press is provided with filter plates supported vertically in a horizontal row in a frame structure and with filter cloth disposed between the filter plates for treating slurries introduced between the filter plates. The filter press includes bars supported at a height above the filter plates to support the filter cloth, shafts disposed orthogonally under the bars, cylinders to move the shafts toward and away from the bars, and vibrators mounted on the shafts to vibrate the shafts. The shafts are moved to come into contact with the bars, and the vibrators are actuated to make the bars vibrate to drop cake remaining on the filter cloth when the filter plates are opened. The filter press further includes photoemissive and photoreceptive devices for detecting deflection and sinking of the bars due to weight of the cake on the filter cloth, and wash pipes for washing down the filter plates and filter cloth.