JP2916363B2 - Sedimentation washer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sedimentation washer which cleans settled sand in a single washing tank, and separates and removes washed sand and screen residue.

[0002]

2. Description of the Related Art In a sewage treatment plant, sediment is washed by stirring the sediment introduced into a washing tank together with washing water by a stirring blade or a jet water stream to separate dirty sand and screen residue. Soil settled to the bottom is filtered by a screw conveyor, and screen residue floating in the water is filtered by a bar screen, and removed individually by a back-rake type dust remover or a filter-type traveling dust remover. ing.

[0003]

Therefore, since these dust removers, such as the back-rake type dust remover, which remove the screen residue, are driven by a chain, the chain requires a take-up device for elongation. Since dust adheres to the chain, a means for removing the attached dust is required, and there is a disadvantage that maintenance becomes complicated.

SUMMARY OF THE INVENTION It is an object of the present invention to separately remove soil and screen residue without using a chain-type dust remover, and to perform a maintenance-free operation.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made to achieve the above object, and has a cleaning tank to which cleaning water and dirty sand are supplied, a cleaning tank at one side bottom, and a cleaning tank at an upper part of the tank. A lower screw conveyor for transferring contaminated sand rotatably provided in a trough portion of a cleaning tank formed with an inclination, and a trough having a semicircular or other arc-shaped cross-section disposed in parallel above the lower screw conveyor. The gist of the present invention consists of a screen-like screen and an upper screw conveyor that is rotatably arranged in the trough-like screen and transfers screen residue captured by the screen upward.

[0006]

In the washing tank, the upper and lower screw conveyors are arranged in parallel and inclined, and the lower screw conveyor is placed in the trough of the washing tank, and the upper screw conveyor is placed in the semicircular trough screen. Each of the tanks is rotatably supported, so that the sand deposited in the tank is washed, and the sediment and screen residue can be separated and taken out, and there is no chain in the drive unit. Maintenance is simplified.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. In the figure, reference numeral 1 denotes a washing tank for dirty sand having a required capacity and shape, and a means for supplying a required amount of washing water and a means for supplying sediment sand scooped up from a sewage treatment plant or the like in the washing tank 1. And means for stirring and washing the settling sand and the washing water supplied in the tank, for example, a stirrer 2 or a jet water jet nozzle as shown in the figure.

The washing tub 1 has its bottom at a position lower than the position where the stirrer 2 is installed, and one side wall of the tub is tilted obliquely upward to a position above the lowest normal water level of the tank. 21 is formed integrally, and a lower screw conveyor 3 for conveying the contaminated sand is rotatably disposed along the truss portion along the truss portion over substantially the entire length thereof, and the lower screw 3 has a lower end thereof. The lower end of the tank and the upper end thereof reach the sedimentation hopper 4 disposed above the washing tank, and are driven at a predetermined speed or adjustable speed by the driving device 3M.

In the washing tank, an upper screw conveyor 5 is provided rotatably in parallel with the lower screw conveyor 3 and inclined upward from the tank bottom to the tank.
Are also driven at an adjustable speed as necessary.

[0010] The upper screw conveyor 5 is used for scavenging sand deposited in the tank by the washing device 2 and removing and removing the screen residue floating in the water by the truss-like screen 6 by scooping. It has a length reaching the screen residue hopper 7 above the sedimentation hopper 4 from the bottom of the tank.

The upper screw conveyor 5 is provided with a truss-like screen 6 having a semicircular shape and other arc-shaped cross sections from a lower portion thereof to at least a position slightly above the maximum allowable water level of the washing tank. At the upper end, a chute 8 having a semicircular cross section having the same shape as the screen is continuously provided on the same axis, and the upper screw conveyor 5 is rotatably arranged in the semicircular truss-like screen and the chute. Is established.

As shown in FIG. 2, the truss-like screen 6 uses a flat bar having a required thickness and width, and the flat bar is formed into a semicircle in the radial direction from the center of the semicircular cross section.
And arranged at a predetermined interval, so that the flat bar interval on the outer peripheral side is larger than the flat bar interval on the inner peripheral side of the truss-like screen, that is, to increase the screen interval in the outflow direction of water, Thereby, clogging due to the screen residue is prevented beforehand.

Therefore, in the sand sedimentation washer constructed as described above, the sediment fed into the washing tank is agitated and washed by a stirring blade or a jet water stream, or a combination thereof, and is formed into a trough shape which becomes a trough portion of an upper screw conveyor. Wash water that has passed through the screen is drained as overflow water, and dust (screen residue) floating in the wash water adheres to the inner peripheral surface of the trough screen and is removed.

Since the upper screw conveyor is rotating, dust adhering to the screen surface is moved upward at the outer edges of the blades of the screw conveyor, that is, conveyed upward, drained through a chute, and then drained. Screen residue hopper 7 arranged at the end of the screw conveyor
Through the tank.

Further, the dirt that has been washed and the floating screen residue has been removed by the screen passes through the eyes of the trough screen and is deposited on the trough at the bottom of the cleaning tank.
However, since the lower screw conveyor is also rotated, the contaminated sand is also transferred upward by the lower screw conveyor and discharged out of the tank from the sand hopper.

[0016]

According to the present invention, there is provided a sedimentation washer in which a washing tank to which washing water and contaminated sand are supplied and a trough section of the washing tank formed at one bottom of one side of the washing tank and inclined at an upper part of the tank. A lower screw conveyor movably provided for transferring contaminated sand, a trough-shaped screen having a semicircular cross-section disposed in parallel above the lower screw conveyor, and rotatably inserted into the trough-shaped screen. Since it consists of an upper screw conveyor that disposes and transfers the screen residue captured by the screen upwards, it cleans the sand,
Separation and removal from the screen residue can be performed at the same time, and since the chain is not used for the drive unit, maintenance is simplified,
It has advantages such as being able to be used continuously.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view showing an embodiment of a sand setting washer of the present invention.

FIG. 2 is a vertical sectional side view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Washing tank 11 Trough part 3 Lower screw conveyor 5 Upper screw conveyor 6 Trough screen

Claims (1)

(57) [Claims] A washing tank to which washing water and dirty sand are supplied;
At the bottom of one side of the washing tank, a lower screw conveyor for transferring dirty sand rotatably provided in a trough portion of the washing tank formed to be inclined at an upper part of the tank, and in parallel with the upper part of the lower screw conveyor. A trough-shaped screen having an arcuate cross section is provided, and an upper screw conveyor is provided rotatably in the trough-shaped screen and transports screen residue captured by the screen upward. A sedimentation washer characterized by that: