JPS58177157A - Apparatus for separating and washing precipitated sand - Google Patents

Abstract

PURPOSE:To make it possible to effectively wash sand only, by removing dirty sand with a particle size of a definite value or less by providing a vibration screen. CONSTITUTION:A vibration screen 7 is provided to a position sunk under the water within a washing water tank 1 while dirty sand is fallen thereon to peel off a contaminant adhered to sand by vibration and a conveyor 1 taking out only sand with a particle size of a prescribed value or more is provided. As mentioned above, the effective washing of only sand is enabled.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is used in water treatment, particularly in the settling basins of sewage treatment plants and pumping stations. This invention relates to a sand separation and cleaning device that allows sand to be transported out.

Traditionally, sludge is washed by mechanically agitating the sludge that has been pumped up indiscriminately from the settling basin without separating it at all, and by applying forced physical agitation through mechanical agitation or air cleaning to remove the filth that has adhered to the sand. I was washing sand. In this case, the object to be cleaned is not necessarily mostly sand, but also the characteristics of the sewage flowing into the settling basin,
Depending on the amount of water, sand with a particle size below a predetermined particle size, which is equivalent to sludge, may be washed, and the cleaning purpose is essentially different, so there is no sand washing effect, and this is a problem at most treatment plants. It had become.

An example of such a conventional sand settling and cleaning device will be explained with reference to FIG. The water depth is maintained at a constant level up to a certain height. (d) is a sludge conveyor, which throws sludge lifted from a settling basin into a washing water tank (α).

An air pipe (1) with a large number of air blowing holes is installed near the bottom of the washing water tank (α), which blows air into the washing water (b) to agitate the washing water and remove dirt. Sludge is separated from the sludge thrown into the wash water (b) from the sand conveyor (d). The sand separated and washed from the sludge in the washing water (b) is conveyed to the washing sand outlet (σ) by a conveyor (f) and taken out to the outside, and the sludge is discharged from a drain pipe (not shown). There is.

Such conventional sand settling and cleaning equipment has the disadvantage that sludge gets mixed into the sand, making it difficult to separate only the sand, and that cleaning is incomplete.

The present invention improves these drawbacks by providing a vibrating sieve at a position submerged in water in the washing tank, dropping dirty sand onto it, and
This relates to a sand settling and cleaning device that uses vibration to peel off dirt adhering to sand and to extract only sand with a specified particle size or larger.

Next, an embodiment of the present invention will be described with reference to FIGS. 2 to 4.

Washing water (2) is supplied to the washing water tank f1) from a washing water supply pipe (not shown), and is maintained at a constant water depth up to a height provided with an overflow trough (3). A screen (4) is attached to the upper side of the washing water tank (1), and a sludge transporter (5) is installed above the screen to transport the sludge transported from the settling basin. It is designed to be dropped onto a screen (4). A screen dust reservoir (6) is attached to the side of the screen (4), and a vibrating sieve (7) for separating and cleaning dirt and sand is installed at a position submerged in water directly below the screen (4). ing.

Vibration @ (71 is slightly tilted so that the left side of Figure 2 is slightly higher and the right side is slightly lower, and is vibrated by a vibrator (not shown). Below the vibrating sieve (7) is equipped with a wastewater bit (8), and a wastewater outlet (9) is connected to the bottom of the bit.Below the vibrating sieve (7), there is also a wastewater bit (8) as shown in Figures 2 and 3. A water backwashing nozzle αα is provided to inject pressurized water from below the vibrating sieve (7) as necessary to clean clogging of the vibrating sieve (7).

The right side of the vibrating sieve (<7) in Figure 2 is the sewage bit (8)
As shown in FIGS. 2 and 4, a conveyor α0 is provided below the conveyor .alpha.0.

The conveyor αυ is a vibrating screen (7) as shown in Figure 2.
It extends above the surface of the cleaning water (2) on the opposite side to a certain position, and is driven counterclockwise in FIG. 2 by a drive device fi3. A washing sand outlet α moat is provided below the upper end of the conveyor αυ.

Next, the operation of this device will be explained.

The filthy sand pumped up in the sand settling pond is transported by a sludge conveyor (5) and falls onto a screen (4). The garbage transported with the dirty sand remains on the screen (4), and the dirty sand passes through the screen (4) and enters the vibrating sieve (2) in the washing water (2).
7) Falling upward. The dirt remaining on the screen (4) is removed by hand or mechanically into the screen dirt sump (6).

The dirt that has fallen onto the vibrating sieve (4) is subjected to minute vibrations by the vibrating sieve (4) in the washing water (2), and the dirt is separated from the sand. For example, fine sand with a grain size of 0.151 or less falls into the sewage bit (8) together with the waste, and large sand with a specified grain size or more falls onto the vibrating sieve (7) according to the inclination of the vibrating sieve (7). It moves while being washed with sand, and sinks to the bottom of the washing tank (1) from the right end of the vibrating sieve (7) in FIG.

The fine sand and filth that have fallen into the sewage bit (8) are returned to the settling basin from the sewage outlet (9), washed with sand, and passed through a vibrating sieve (
7) The sand of a specified particle size or more that has settled to the bottom of the washing water tank (1) from the end of the washing water tank (1) is conveyed while being drained to the upper part of the washing water tank (1) by a conveyor ELL, and is taken out as washed sand from the washing sand outlet 03. It will be done. The washed sand thus removed is reused as aggregate for concrete.

As described above, in the present invention, a vibrating sieve is provided to remove dirty sand with a certain particle size or less as waste water along with filth, and only sand with a certain particle size or more that needs to be removed is washed by vibration in a washing tank. Therefore, only the sand that needs to be carried out can be effectively washed.

[Brief explanation of the drawing]

FIG. 1 is a vertical side view of a conventional device, FIG. 2 is a vertical side view of an embodiment of the present invention, and FIGS. 3 and 4 are a sectional view taken along the line m and IV in FIG. It is. (1)...Washing tank, (5)...Dirty sand conveyor, (Power...Vibration sieve, (8)...Sewage pit, (9)...
Sewage outlet, αυ... conveyor, (13... sand washing outlet. Patent applicant Ishikawajima Harima Heavy Industries Co., Ltd.

Claims (1)

[Claims] 1) A vibrating sieve installed in a submerged position in a washing water tank for separating and cleaning dirty sand, a sewage pit capable of storing and discharging the sewage and fine sand that have passed through the vibrating sieve, and the vibrating sieve. A conveyor for transporting sand that does not pass through the washing tank to a washing sand outlet of the washing tank.