JPH0220002Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a solid-liquid separation tank that effectively separates solid matter in liquid such as sand in sewage in sewage facilities.

[Prior art]

Conventional settling basins at sewage treatment plants guide the sewage flowing in from the sewage pipes into an extremely large rectangular water tank, which significantly reduces the flow velocity and allows solids such as sand with a high specific gravity to settle to the bottom. The accumulated solids were removed by mechanically scraping them with a rake or the like. Therefore, conventional sand settling basins require an extremely large installation area, and also require mechanical equipment to scrape up and remove accumulated sand and the like.

(Problems to be solved by the invention) In order to improve such drawbacks, a solid-liquid separation device using swirling flow has been invented, for example, as shown in Japanese Patent Application Laid-open No. 59-109632, but in this case, This method has a problem in that a portion of the solid-liquid substances such as sand in the liquid to be treated that enters from the inlet flows out from the outlet, resulting in insufficient separation.

Further, when the outlet is located below the inlet, the liquid in the inlet channel is not full and has a free surface, making it difficult to control the inflow velocity, and the flow velocity is sometimes too high to prevent precipitation.

Also, as a solid matter separator
It is known that the outlet is placed at a higher position than the inlet, and a buttful is provided between the two, but the buttful only leaves a small hole and covers most of the cross section of the tank, allowing solids to flow through the tank. Solids are allowed to precipitate in the chamber below this butthole, and the purified water from the upper part is passed through the hole and led to the upper chamber where it flows out. Therefore, the lower chamber was quite large and it was difficult to downsize it.

An object of the present invention is to solve these problems and provide a solid-liquid separation tank that can separate and efficiently treat a large amount of sewage with a relatively small installation area.

[Means for solving problems]

The present invention has a substantially circular side wall and a bottom surface,
A solid-liquid separation water tank in which solid-liquid separation is performed while swirling a liquid to be treated stored therein, is provided with an inflow path for the liquid to be treated tangentially connected to the side wall, and at least one of the inflow ports at the end of the inflow path is provided. A separation plate extending into the tank at or higher than the upper edge of the inlet is provided over the width of the upper edge, and the treated liquid is placed in the tank above the separation plate and near the inlet. This is a solid-liquid separation water tank characterized by having an open outlet that leads to the outside.

[Effect]

The present invention is configured as described above, and a smooth upward swirling flow is formed as the main flow in the tank from the inlet to the outlet.

The raw water that flows in from the inlet is guided under the separation plate and enters the tank, and the purified water that approaches the outlet becomes a horizontal swirling flow while being guided above the separation plate and is sucked into the outlet. .

At this time, the raw water flowing in from the inlet and the purified water guided to the outlet on the separation plate are actively separated by the separation plate, so the raw water is not directly discharged or the degree of purification is increased by bending. This prevents water with a low degree of purification from being mixed into the water and lowering the degree of purification again, and high separation efficiency can be obtained with a short channel (spiral upward swirling channel). A large amount of sewage can be separated and treated efficiently with a small device.

It is known that when sewage is swirled in a water tank, a "secondary flow" occurs in a plane perpendicular to the swirling flow. This secondary flow flows toward the outer wall of the tank in the upper part of the swirling flow, and flows toward the center of the tank in the opposite direction to the wall in the lower part of the swirling flow. Therefore, solid matter such as sand that has accumulated on the bottom of the aquarium tends to be pushed toward the center, so it is preferable to effectively collect the sediment at the bottom of the tank in the center and drain it using a pump or the like. be.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

In FIGS. 1a and 1b, the solid-liquid separation tank 1 is
It has a side wall 2 and a bottom surface 3 that are approximately circular (circular, oval, oval, similar circular shape, or spiral shape). In this water tank 1, an inflow channel 4 whose end opens at an inlet 5 is provided in a tangential direction to the side wall 2 to introduce a liquid to be treated, such as sewage, in a tangential direction to the side wall 2 and give a swirling motion to the liquid in the tank 1. establish. The position of the inflow port 5 may be such that a part thereof is on the bottom surface 3.
Alternatively, it may be placed only on the bottom surface 3. The bottom surface 3 is inclined from the outer periphery toward the center. The bottom surface 3 may be formed horizontally, but it is more effective to have it sloped in order to collect the precipitable solids in the center of the bottom surface.

A discharge pipe 6 having a pump 6a is inserted from above into the sediment receiver 3a near the center of the bottom surface 3 of the water tank 1 to serve as a concentrate discharge section for guiding the concentrated liquid containing a large amount of separated solids to the outside of the tank. Precipitable solids contained in the liquid are accumulated at the bottom by swirling flow and secondary flow, and are discharged out of the tank as a concentrated liquid together with the liquid to be treated.

A water outlet 9 is provided in the side wall 2 of the water tank 1. The discharge port 9 is preferably provided at a position slightly downstream of the inlet 5 on the circumference of the side wall 2 along the flow direction of the swirling flow, and at a position of up to 180°. Further, its height is set higher than the inlet 5. A substantially horizontal separation plate 10 is provided midway between the heights of the inlet 5 and the outlet 9 and extending along the direction of the swirling flow from the inlet 5 to the outlet 9. That is, the separation plate 10 is extended into the water tank 1 over a width larger than the upper edge width of the inlet 5 at a position higher than the upper edge of the inlet (in this embodiment, a slightly higher position), and is separated. Board 10
An outlet 9 is provided above the inlet 5 near the inlet 5 .

Sewage mixed with solids such as sand flows into the water tank 1 from the inlet 5 via the inlet channel 4, and swirls along the side wall 2 as shown by the arrow. With the swirl of the flow,
Sand and the like in the sewage settles to the bottom surface 3. For swirling flows, secondary flows 7 occur, as described above. Due to the secondary flow 7 directed toward the center of the bottom surface and the slope of the bottom surface 3, the settled sand 8 is pushed toward the center and collected in the sand receptacle 3a. When the amount of sand in the sand receiver 3a reaches a certain level or more, the pump 6a is operated to suck up the concentrated content including solid matter such as precipitated sand through the discharge pipe 6 and discharge it to the outside.

The main flow of the sewage being purified is guided in a spiral upward spiral movement past the separator plate 10 towards the outlet 9. Since the outlet 9 is located directly above or in the vicinity of the inlet 5,
The sewage flows through approximately 360 degrees or more within the water tank 1, and solid matter such as sand can be sufficiently separated.

In addition, due to the separation action of the separation plate 10, inflowing sewage and purified sewage do not mix, and the inflowing sewage flows directly into the straight outlet 9 without separating sand, etc. There's nothing to do.

Furthermore, since the outlet 9 is located above the inlet 5, the inlet channel 4 will not be filled with sewage and create a free surface. Therefore, since the inflow speed is easily controlled and the turbulence of the flow is small, the settling of sand etc. is not hindered.

Next, in FIGS. 2a and 2b, the solid-liquid separation tank 1 has a substantially circular side wall 2 and a bottom surface 3 that slopes toward the center, similar to that shown in FIGS. 1a and 1b.
A discharge pipe 6 equipped with a pump 6a is inserted into a sediment receptacle 3a provided near the center of the bottom surface.

Thus, the inflow channel 4 provided tangentially to the side wall 2 extends into the interior of the water tank 1, and the inflow port 5 at its end opens into the tank. In this case, the upper wall of the inflow path 4 also serves as the separation plate 10. The flow of sewage is the same as in Figures 1a and b.

[Effect of idea]

Since the present invention is configured as described above,
Not only is sufficient separation carried out while the inflow water rotates at least approximately 360 degrees within the tank, but it also prevents raw water from being directly discharged, or contaminating water with a higher degree of purification with water of a lower degree of purification. This prevents the degree of purification from decreasing again, and allows high separation efficiency to be achieved with a short flow path (spiral ascending swirl flow path). Therefore, a large amount of sewage can be separated efficiently with a small device. In addition, a stable secondary flow is formed, and the sediment at the bottom of the tank is effectively collected in the center, making it easy to discharge, which is extremely effective in practice.

[Brief explanation of drawings]

1A and 1B are a plan view and a sectional side view of an embodiment of the present invention, and FIGS. 2A and 2B are a plan view and a sectional side view of another embodiment. 1...Aquarium, 2...Side wall, 3...Bottom surface, 3a...
...Sand receptacle, 4...Inflow channel, 5...Inlet, 6...
Discharge pipe, 6a... pump, 7... secondary flow, 8...
...Sand, 9... Outlet, 10... Separation plate.

Claims (1)

[Scope of utility model registration request] In a solid-liquid separation water tank that has a substantially circular side wall and a bottom surface and performs solid-liquid separation while swirling a liquid to be treated contained therein, an inflow path for the liquid to be treated is connected tangentially to the side wall. a separation plate extending into the tank at or higher than the upper edge of the inflow port over at least the width of the upper edge of the inflow port at the end of the inflow passage; A solid-liquid separation tank, characterized in that a discharge port for guiding the treated liquid out of the tank is provided near the inlet.