JPS6329569B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for scraping dirt from the surface layer of a filter sand layer of a slow filtration basin.

As filtration continues, the surface layer of the filter sand layer becomes contaminated by the accumulation of filter foreign matter. In the case of rapid filters, filter foreign matter is removed by backwashing. In the case of slow filtration basins installed in waterworks plants, etc., the sand layer surface layer contaminated with filtration foreign matter is scraped and removed without backwashing.

Slow filtration basins are usually installed with a plurality of filtration basins of the same size adjacent to each other. When the contamination of the filter sand progresses, one of the ponds is shut down and the water drained, and then workers enter the pond and manually scrape off the surface dirt from the filter sand layer. The work of removing dirty sand is 1.
This is done on a monthly cycle, about once per pond, and it is necessary to scrape off a layer thickness of about 1 cm. This work, as well as the processing work such as transporting the scraped dirt and washing the sand, requires considerable effort, time, and cost.

The present invention is capable of automatically scraping or scraping the surface dirt of the filter sand layer and discharging it without draining the water from the slow filtration basin and leaving it in a water-filled state without manual labor. This provides a device with a simple configuration and low cost.

The automatic dirt scraping device of the present invention consists of a float section that is equipped to be able to move vertically and horizontally on the water surface of a slow filtration basin, and a scraping section that is attached below the float section so as to be able to move up and down. The scraping section includes a roller rotatably supported in contact with the pond bottom filter sand layer, a rotating screw-type scraping conveyor installed parallel to the roller axis,
A guide plate formed on a scraper that covers at least the rear of the screw-type scraping conveyor and whose lower edge is located at a certain depth in the filter sand layer, and a pump that discharges the scraped sand together with water to the outside of the filter basin. It is characterized by being configured.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below with reference to embodiments shown in the accompanying drawings.

The device of the present invention consists of a float part 1 and a scraping part 2. As shown in FIG. 3, in this example, the slow filtration basins include four basins A, B, C, and D arranged in a row in the direction of arrow Y. Regarding directions perpendicular to the Y direction, the X direction on the right in the figure is the front, and the X' direction on the left is the rear.

Rails 4 and 4' are laid in the Y direction on the front side wall 3 and rear side wall 3' of the row of ponds, respectively.
Bogies 5 and 5' are mounted on the rails 4 and 4, and the bogies 5 and 5' run synchronously.

A wire rope 7 is stretched in the X-X' direction across pulleys 6 and 6' on the carts 5 and 5',
The float part 1 is connected to a wire rope 7 via a connecting wire 8. In this way, the float part 1 floats on the water surface W in the pond and can be moved vertically and horizontally in the X--X' direction by the rotation of the pulleys 6, 6, and in the Y direction by the running of the carts 5, 5. Trolley 5
has a lifting device 9 whose purpose will be described later.

The scraping section 2 is connected to the lifting device 1 downward from the float section 1.
0. In this example, the lower frame 11 is attached in a suspended state by a parallelogram link mechanism. Rollers 12 and 12' are rotatably supported by pivot parts 13 at the front and rear of the lower frame 11 of the scraping part, and are in contact with the pond bottom filter sand layer S to regulate the descending height of the device and prevent its movement in the forward X direction. It is guiding. A screw-type scraping conveyor 14 is provided between the front and rear rollers 12, 12' and extends in the left-right direction in parallel with the roller axis. Rotationally driven. The screw-type scraping conveyor 14 has a right-handed screw and a left-handed screw, and is configured to scrape from the left and right ends toward the center as it rotates.

A guide tube surrounding the screw of the conveyor 14 is formed into a guide plate 19 that is open downward in the front and covers the upper rear, at least the rear. And information board 19
The lower edge of is formed into a sharp edge scraper 20, which is positioned at a constant depth in the filter sand layer S with the rollers 12, 12' in contact with the surface of the filter sand layer S. This depth is, for example, several mm to several tens of mm, and corresponds to the thickness of the scraped surface layer.

With the rollers 12, 12' in contact with the filter sand layer S, the elevating device 10 is tilted so that the lower it is, the more rearward it is. Hoisting device 2 on the float part 1 on the front link
Connect 1 with wire. Thus rollers 12,1
2', a conveyor 14, a guide plate 19, etc., the scraping section 2 is movable up and down relative to the float section 1.

A suction port 22 at the center of the guide plate 19 corresponding to the raking center is connected to a suction pump 24 mounted on the float part 1 via a flexible suction hose 23. The suction pump 24 is connected to a predetermined relay discharge point 26 outside the filter basin via a flexible hose 25 floating on the water surface. The relay discharge point 26 is selected at a location that can be shared by two adjacent ponds. Transfer from the relay discharge point to the aftertreatment facility is carried out by means of a relay pump (not shown).

The suction pump 24 can be provided in the scraping section 2. One example of the planar dimensions of a slow filtration basin is 30m x 40m. If the filtration basin is small, the means for discharging dirt from the suction pump 24 to the outside of the filtration basin may be replaced by a running trough running over the carts 5, 5' instead of the hose 25, and a discharge groove provided on the outside of the side wall 3 or 3'. It may also be discharged at

The scraping part 2 is lowered onto the filter sand layer S, and the pulley 6,
When the wire rope 7 is driven by 6' and pulled forward in the X direction, the sharp edge scraper 2 of the guide plate 19
0 scrapes solidified dirt at a certain depth from the surface layer of the filter sand layer S. At the same time as scraping, the screw-type scraping conveyor 14 is driven, and the scraped coagulated dirt is loosened by the screw and scraped to the center. At the same time, the suction pump 24 is operated, and the collected dirt is sucked together with water through the suction hose 23 and discharged through the hose 25 toward the relay discharge point 26.

When the scraping device reaches the front side wall 3, the operation of the wire rope 7, screw-type scraping conveyor 14, and suction pump 24 is temporarily stopped, and the hoisting device 21 is activated to lift the scraping unit 2 from the sand layer S. The separating wire rope 7 is moved backward to move the scraping part 2 in the X' direction and return it to the position of the rear side wall 3'. The scraping device is moved in the Y direction by the scraping width using the carts 5 and 5', and scraping of the adjacent zone in the X direction toward the front side wall 3 is started again.

By repeating this operation, once the waste scraping of one pond is completed, the scraping device can be lifted up by the lifting device 9 and transferred from pond B to pond A in Fig. 3, for example, in order to scrape the next pond. can. Transfer to ponds C and D is possible by once disconnecting the hose 25 and the relay discharge point 26.

If scraping remains along the side walls 3, 3' due to the design of the scraping unit 2, the scraping unit is disconnected from the wire rope 7 by the connecting wire 8, lifted by the lifting device 9, turned 90 degrees, and suspended. It can be connected to the upper device 9 and pulled to perform scraping in the Y direction.

According to the present invention described above, the following effects can be obtained.

(1) Because the waste sand in the slow filtration basin is scraped, the process of draining water before scraping and backwashing and filling with water after scraping becomes unnecessary.

(2) The waste sand is forcibly washed during the transfer process using the loosening suction pump in the scraper of the scraping conveyor, eliminating the need for sand washing equipment, making post-processing easy.

(3) Scraping is possible even if the water depth of the filtration basin changes.

(4) There are no facilities such as water gutters or bridges on the pond, and the structure is relatively simple and inexpensive.

[Brief explanation of the drawing]

Fig. 1 is a side view of one embodiment of the automatic dirt scraping device of the present invention, Fig. 2 is a partial cross-sectional plan view of the unkuriyu-type scraping conveyor portion, and Fig. 3 is an implementation of the present invention in a slow filtration basin. FIG. 2 is a plan layout diagram of an example device. 1... Float part, 2... Scraping part, 3... Front side wall, 3'... Rear side wall, 4, 4'... Rail,
5, 5'... Truck, 6, 6'... Pulley, 7... Wire rope, 8... Connection wire, 9... Lifting device, 10... Lifting device, 11... Lower frame, 12,
12'...Roller, 13...Pivotal part, 14...Screw type scraping conveyor, 15...Motor, 1
6, 18... Chain wheel, 17... Chain belt, 19... Guide plate, 20... Scraper, 21... Hoisting device, 2
2... Suction port, 23... Suction hose, 24... Suction pump, 25... Hose, 26... Relay discharge point, A, B, C, D... Filtration basin, X, X', Y...
...Directional arrow, W...Water surface, S...Filter sand layer.

Claims (1)

[Claims] 1 The slow filtration basin is connected to the wire rope of a traction device, in which a traction rope is hung between the pulleys on the bogie running on the opposite side walls of the slow filtration basin, and the synchronous running of the bogie and the forward and reverse rotation of the pulley drive the slow filtration basin. It consists of a float part that can move vertically and horizontally on the water surface, and a scraping part that is attached to the lower end of the float part via a lifting device that is suspended from the float part and can be rotated backwards to be hoisted up. rollers are provided before and after the filter sand layer to support the scraping part on the sand layer surface, and rollers are provided parallel to the roller axis between the front and rear rollers to collect the scraped dirt from the surface layer of the filter sand layer in the center. It has a rotating screw-type scraping conveyor that scrapes, and a scraping tip consisting of a scraping scraper that is formed on the lower edge of the guide plate that covers from the rear to the top of the scraping conveyor and is located at a certain depth in the filter sand layer. An automatic dirt scraping device for a slow filtration basin, characterized in that it is equipped with a suction pump that discharges the dirt collected at a collection point to the outside of the filtration basin together with water.