JPS599205B2 - Sediment scraping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a raking device provided in an intermediate tank and a lower tank of a multi-layered sedimentation tank, and more particularly to a device for raking sediment and scum adhering to a ceiling surface.

Sewage treatment facilities installed in densely populated areas have become increasingly dependent on multi-layered sedimentation ponds, as the amount of water they need to treat has increased and it has become difficult to secure a sufficient amount of land for sewage treatment facilities.

However, in multi-layered sedimentation tanks, the problem of scum adhering to the ceiling surface peeling off in layers and floating within the layer occurs again and again, and a device is required to scrape up the sediment from the bottom of the pond as well as scrape up the scum from the ceiling surface. It became so.

A device for scraping up such sediment and scraping scum is provided, for example, in the intermediate and lower sedimentation tank 1 as shown in FIGS. Wheels 2 to 5 are arranged, and a pair of rotary chains 8 are suspended from the wheels 2 to 5 so as to circulate around the pond bottom 6 and the ceiling 7 on both sides of the pond over approximately the entire length ζ of the pond.

A sediment scraping plate 9 is fixed to the chain 8 in parallel at appropriate intervals, and a swingable C is provided between the sediment scraping plate 9.
A scum scraping plate 10 which can be pivotally fixed is provided.

In addition, the running rail 11 of the raking board 9 is on the bottom side of the pond, and the raking board 9 is on the ceiling side.
A support rail 12 is provided.

In this way, the scum scraper 9 moving on the traveling rail 11 scrapes up the sediment, while the scum scraper 10 suspended via the chain 8 swings between the scrapers 9 moving on the support rail 12. At the same time, he scraped up the scum from the seven sides of the ceiling.

However, since the sediment scraper 9 runs supported by the rails 11 and 12 and the scum scraper 10 is suspended between the sediment scrapers 9 via the chain 8, the scum scraper 10 Since the running of the tank is insufficiently regulated and fluctuates freely, the contact with the ceiling surface is unstable and may interfere with the pond bottom and sediment.

Further, the running surface of the sediment scraping plate 9 has the drawback that the weight of the sediment scraping plate 9 and the weight of the chain 8 and the scum scraping plate 10 are added to increase the rotational resistance.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks, to provide a scraping device that scrapes scum stably and has low rotational resistance.

The key points of this invention are that a plurality of buoyant scraping boards are attached to an endless band that is rotatably provided in the pond, and a rail is provided on the pond bottom that touches the top surface of the scraping board, so that the scraping board is placed on the bottom of the pond. When passing through the pond, a rail presses down on the raking board to scrape up the sediment, and when passing over the top of the pond, the buoyant force is used to scrape across the ceiling.

Embodiments of the invention will be described based on the drawings.

Identical parts in FIGS. 3 and 4 are designated by the same reference numerals as in FIGS. 1 and 2.

In both figures, scraping plates 13 are fixedly protruding from the chain 8 in parallel at appropriate intervals.

A rail 15 is provided near the bottom of the sedimentation tank 1 via a bracket 14 protruding from the side wall of the sedimentation tank 1 and in contact with the upper surface ζ of the scraping plate 13.

It is optional to provide wear-resistant sliding contact pieces 16 and 17 at the portion where the scraping board 13 makes sliding contact with the surface of the sedimentation tank ceiling 7 and the rail 15.

Next, the effects of the above configuration will be described.

The raking board 13 is pulled by the chain 8 and circulates in the pond, and when moving along the upper side of the pond, it slides against the surface of the ceiling 7 due to the buoyancy of the raking board and scrapes up scum, and when moving along the bottom side of the pond, it scrapes up the scum. Board 13
This is because of the buoyant force (by which the upper surface of the raking board 13 slides against the rail 15 and the sediment is raked along the pond bottom 6).

As described in the above structure and operation, this invention uses a buoyant scraping board on an endless band that rotates in the pond. By installing a rail on the pond bottom side that slides against the top surface of the raking board, the raking board slides against the ceiling surface and moves along the pond bottom C, so the raking board prevents scum and This makes it possible to scrape up the sediment.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing a conventional sedimentation tank scraping device, Fig. 2 is a detailed view showing the same scraping plate, Fig. 3 is a longitudinal cross-sectional view showing an embodiment of the present invention, and Fig. 4 is a cross-sectional view showing a conventional settling tank scraping device. It is a cross-sectional view in an example. 1: Sedimentation tank, 8: Rotating chain, 9: Sediment scraper, 13:
Kakiyose board, 15: Leru

Claims (1)

[Claims] 1 Sediment raking device Q for a multi-layered sedimentation basin is provided with a rotatable endless band so as to circulate on the upper and lower surfaces of the sedimentation tank, and a buoyant raking plate is fixed to this endless band, so that it runs along the bottom of the basin and as above. A sediment scraping device characterized in that it is constructed by providing a rail that slides on a scraping board.