JPS5916084Y2 - Sedimentation tank for wastewater treatment - Google Patents

Description

[Detailed description of the invention] The present invention relates to a settling tank for the purpose of treating gray water.

As is well known, public sewage facilities are generally used to treat gray water, and in areas where sewage facilities are not well-developed, wastewater is treated by discharging it into rivers, gutters, etc., or by sucking it into the soil. There is.

Currently, there are no particular problems when discharging into sewers, but when discharging into rivers, etc., when pollutants flow in at a scale that exceeds the natural purification effect, sludge accumulates in rivers. In rice fields, eutrophication often causes problems such as poor growth of crops due to eutrophication.

The main sources of gray water are domestic kitchens, baths, laundry, and washrooms.

Among these, wastewater from kitchens contains a lot of solid content such as vegetable scraps, and wastewater from baths, laundry, and washrooms contains hair, detergent, etc., but the content of pollutants is much higher than that from kitchen wastewater. few.

Furthermore, pollutants in wastewater include organic matter and inorganic matter.

When organic matter decomposes in water, it requires oxygen in the water, so it is said that one grain of leftover food consumes approximately 31 times the amount of oxygen in the water, which is equivalent to the amount of oxygen consumed by wastewater containing pollutants in a certain period of time. The amount is a measure of organic pollution and is called BOD (Biochemical Oxygen Demand).

Some pollutants are dissolved in water, but most are in solid form, which is called suspended solids (SS) and is a major source of pollution in wastewater.

Therefore, the key point in wastewater treatment is to precipitate and remove SS in wastewater.

The ideal treatment for wastewater is an aeration method in which organic matter is decomposed by microorganisms while supplying air through agitation, but a simple method that separates and removes solid matter is also quite effective, and from this point of view, various methods have been proposed. Sedimentation tanks have been put into practical use and are actually used buried in homes.

Generally, these settling tanks have a small internal volume of 501
The large size is about 2001, and the shape is square.
It has a cylindrical shape, and the interior is divided into two or more chambers, including an inlet, an outlet, and a filtration chamber.

The material of the main body is FRP (glass fiber reinforced plastic)
, plastic, concrete, etc.

By passing these sedimentation tanks, SS and B in the wastewater are removed.
Although the OD can be reduced considerably, the problems are (1) The capacity is small, so it is necessary to remove the accumulated sludge once every week or 10 times, which means that cleaning and management are not easy. The filter media is easily clogged with sludge, which often causes the filter media to become clogged.

In view of the current situation, the inventors of the present invention have studied various structures of sedimentation tanks and have devised a sedimentation tank that is easy to clean and causes fewer troubles such as clogging of filter media.

That is, the present invention consists of a plurality of sedimentation chambers, and a cage equipped with a filter at the bottom is removably inserted into some or all of the sedimentation chambers, and the lower discharge port of the previous sedimentation chamber of the sedimentation chamber into which the cage is inserted is opened. It is provided so that the settled sludge falls into the cage in the next stage settling chamber, and an example of its implementation will be described below based on the drawings.

The settling tank of this example includes four large and small settling chambers 1 to 4,
In the second and fourth settling chambers 2 and 4, cages 5 and 6 each having a filter a at the bottom are removably inserted.

In this example, cloth is used as the filter a, and the basket 5
, 6 on the bottom inner surface.

The cages 5 and 6 are respectively inserted into the precipitating chambers 2 and 4, that is, the bottoms 1a and 3a of the precipitating chambers 1 and 3 are the downstream settling chambers 2 and 4, respectively.
It has a structure that is higher than the bottom of the cage 4 and has an inclined structure so that the settled sludge flows into the cages 5 and 6 through the lower discharge ports 1b and 3b.

Furthermore, the partition wall 7 between the settling chambers 2 and 3 is made lower than the peripheral wall of the tank, so that the supernatant water overflows from the settling chamber 2 to 3.

Furthermore, the cage 6 is provided with a filter medium 8 at the upper part, and a flow control plate 9 is provided at the discharge port 3b of the settling chamber 3 so that the flow is advected in two stages, upper and lower.

Now, the waste water from the kitchen etc. passes through the drain pipe 10 and flows into the first settling chamber 1 from the inlet 11.

This first sedimentation chamber 1 serves as a flow rate adjustment chamber provided to prevent the water in the sedimentation tank from being agitated even if a large amount of bathtub waste water flows in in a short period of time, and the bottom portion 1a has a diagonal structure.
The sludge is designed to advect into the second settling chamber 2 in the adjacent room.

The waste water that has flowed into the second precipitation chamber 2 overflows from the partition wall 7 into the third precipitation chamber 3.

Grasp the handle 5a of the cage 5 inserted into the second settling chamber 2 and pull it up little by little.The water in the sludge in the cage is separated by the filter a, and the sludge is concentrated and its weight when pulled up is reduced. Ru.

If the lifted cage 5 is left on the ground for a while, the sludge is further dehydrated and can be easily removed from the filter.

In normal use, filter a is cleaned every 10-15 days.

The bottom 3a of the third precipitation chamber 3 has an oblique structure as described above.

Since the flow control plate 9 is provided at the discharge port 3b, the water containing sludge in the third settling chamber advects to the fourth settling chamber 4 from below or above the flow control plate 9.

The settled sludge advected from the lower side of the flow control plate 9 is transferred to the fourth settling chamber 4.
The waste water that falls into the cage 6 and advects on the upper side flows into the fourth settling chamber 4 and causes turbulence, thereby preventing clogging of the filter medium 8.

The treated wastewater that has passed through the filter medium 8 is discharged from the discharge port 12 to the drain pipe 1.
Flows into 3.

When the flow of water stops, the sludge in the fourth settling chamber 4 (filtration chamber) settles in the filter a, and even if water starts moving again, the sludge that has settled once will not be rolled up by the water.

The sludge settled in the cage 6 of the fourth settling chamber 4 can be easily removed by grasping the handle 6a of the cage, pulling it up, and dewatering it.

As described above, the settling tank according to the present invention allows sludge to be removed very easily and is easy to manage, and is particularly suitable for practical use as a settling tank for treating gray water.

[Brief explanation of the drawing]

Figure 1 is a plan view of this embodiment, Figure 2 is a sectional view taken along line A-A,
3 is a sectional view taken along the line -B in FIG. 1; 1 to 4... Sedimentation chamber, 5 and 6... Basket, a... Filter

Claims (1)

[Scope of utility model registration request] Equipped with four large and small precipitation chambers 1 to 4, the second and fourth precipitation chambers 2
, 4 are removably inserted into the cages 5 and 6 equipped with filters a at the bottom, and the bottoms 1 and 4 of the first and third settling chambers 1.
a, 3a are higher than the bottoms of the latter settling chambers 2, 4, respectively, and are inclined, and lower discharge ports 1b, 3b are provided so that the settled sludge flows into the cages 5, 6, and the second and third The partition wall 7 of the settling chambers 2 and 3 is lower than the peripheral wall of the tank, and a filter medium 8 is provided on the upper part of the basket 6, and the discharge port 3b of the third settling chamber 3 has advection in two stages, upper and lower. A sedimentation tank for wastewater treatment, characterized in that a flow control plate 9 is provided so as to.