JPS6022140B2 - Drainage and rainwater collection methods and devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for collecting wastewater and rainwater, and more specifically, to a method and apparatus for collecting wastewater and rainwater, and more specifically, a method for collecting wastewater and rainwater from factory premises, such as wastewater and rainwater that do not contain oil or other chemicals, and using the wastewater as industrial water. This invention relates to a method and device for collecting drainage and rainwater for the purpose of.

Japan has long been said to be a country rich in water, but with the rapid development of industry and population growth, the amount of water used has also increased, making it difficult to meet demand with natural water alone.

For this reason, in industry, cooling water is recycled,
Treated water obtained by purifying sewage and other wastewater through biochemical treatment such as activated sludge method is reused. The amount of water used is expected to increase year by year, so securing the amount of water used is an important issue. In order to solve this problem, the present inventors examined the relationship between water and wastewater, and researched ways to circulate and use a limited amount of raw water and to utilize rainwater.

- There are many different types of industrial wastewater, but taking wastewater from oil refining as an example, it is classified into non-oil-containing wastewater, oil-containing cooling wastewater, process wastewater, and sanitary wastewater, and each is collected and treated for purification if necessary. After that, they are released.

The main purpose of the present invention is to collect wastewater and rainwater that do not contain oil or other chemicals in product leakage-free areas on factory grounds such as oil refineries, petrochemical plants, and steel mills, and to reuse them as water for use.

In factory wastewater measures, rainwater accounts for about 40~40% of the total wastewater volume.
It accounts for 60%, and the drainage equipment is approximately 2-2% during normal operation.
．． It is customary to install one with five times the capacity. However, according to the present invention, a portion of the rainwater is collected and used, so that the drainage equipment of the main pot can be downsized. The present invention uses a water-permeable material to form a water-permeable layer on the ground surface of a non-product leakage area within the factory premises to allow drainage and rainwater to pass through, and furthermore, the lower layer of the water-permeable layer is formed as a sand and sand layer made of earth and sand with a low effective water content. Drainage water and rainwater are passed through the soil layer, purified by the self-purifying action of soil microorganisms, and guided to a water collection pond whose side walls and bottom are made of impermeable material.
Next, the wastewater and rainwater are introduced into a water intake tank provided in a part of the water collection basin, the side walls and the bottom of which are made of permeable material, and the thus collected water is pumped into the water intake tank. A drainage and rainwater collection method characterized by a mechanism capable of pumping water above the ground surface,
Furthermore, a water collection pond is formed by excavating a product leak-free area within the factory premises, and the bottom and side walls are made of non-lacquered material. At the same time, a water intake tank is provided, and the outside of the water intake tank is filled with ±sand with a low effective water content to form a ±sand layer, and a water-permeable material is provided from above the soil layer to the ground surface. This drainage and rainwater collection device is characterized in that it has a layered structure and is equipped with pumping means for guiding the water in the water intake tank onto the ground surface.

The present invention will be explained with reference to the drawings.

・Figure 1 is an explanatory diagram. A part of the product leak-free area on the factory premises is excavated, and the bottom (above the groundwater level 1) and side walls are made of impermeable material to create a water collection pond. to form.

Impermeable materials include concrete, asphalt, metal plates,
Any material can be used, such as a synthetic resin plate or a synthetic resin sheet, but a material with high flexibility, such as silt cement, is preferred because it has excellent workability. The size and shape of the catchment pond should be selected appropriately, taking into consideration the surrounding conditions. A water intake tank 3 is installed in a part of the blind water pond 2. Details of the water intake tank 3 will be described later.
Other spaces in the water collection pond 2 are filled with ±sand with a low effective moisture content. Examples of such ± sand include gravel, tsumugi sand, coarse sand, and tsumugi sand. The reason why the soil layer 4 is formed in the water collection pond is to effectively utilize the underground self-cleaning action of soil microorganisms and the like. Note that, prior to filling this earth and sand, it is preferable to fill the periphery of the water intake tank with crushed stone or gravel, gravel, and coarse sand in this order from the inside to the outside so that the water can be easily drained. The upper part of the earth and sand layer 4, that is, the ground surface, is a permeable layer 5 made of a permeable material. The thickness, strength, porosity, etc. of the layer are selected depending on the purpose. The permeable material used here is preferably porous asphalt concrete. Porous asphalt concrete has a small particle diameter and 3-6% based on the weight of the bone.
asphalt and generally has a porosity of 20 to 45%. Note that crushed stone is preferable as the aggregate, but sand, gravel, metal particles, coke, etc. can be used alone or in combination. The particle size of the aggregate is preferably about 1.5 to 10 ribs. Asphalt functions as a binding material, and various types such as straight asphalt, blown asphalt, and cat's blown asphalt can be used. As binding aids, for example natural or synthetic rubbers (
Particularly preferred is rubber latex. ) or epoquine resin can be mixed. If the porosity of porous asphalt concrete is less than 20%, the water permeability will be insufficient, and if it exceeds 45%, the strength will be insufficient, which is not preferable. An example of the composition of porous asphalt concrete is: 100 parts by weight of crushed stone with a particle size of 2.5 to 5 grains;
There is one that consists of 6 parts by weight of filler (such as calcium carbonate) and 4.5 parts by weight of asphalt, and has a porosity of 35%.
On the other hand, any means for guiding the non-oil-containing wastewater to the water collection pond may be used, such as providing a drainage ditch or arranging a conduit on the ground or underground.

In this case, it is preferable to be able to adjust the amount of inflow of wastewater. Blocks 6 etc. will be placed around the water collection basin on the ground to make it slightly higher than the ground level.

FIG. 2 is an explanatory diagram showing details of the water intake tank 3.

The intake tank will be placed about 20 to 30 degrees above the bottom of the water collection basin, and the space will be filled with crushed stone or gravel. The bottom and side walls of the water intake tank are made of water permeable material 7. As the water-permeable material, the above-mentioned porous asphalt concrete is preferred. The size, shape, etc. of the water intake tank will also be determined as appropriate, taking into consideration the purpose of use and other factors. It is not preferable to use a reinforced concrete perforated pipe as a water intake tank because the flow rate of water from the hole is high and the inflow of sand, sediment, etc. is unavoidable.

When porous asphalt concrete is used, water permeates through the entire surface of the clay, and the inflow rate can be adjusted as desired, making it easy to achieve a rate of 3 skins/sec or less, which was previously considered impossible.

Even if the inflow speed is slow, the inflow amount will not decrease because it can flow from the entire surface of the dam. When installing a water intake pipe, the installation slope should be 1/500 or less, and the average flow velocity at the outlet end should be 0.
．． It is desirable that the speed be 3 m/sec or less.

It is desirable that the side wall surface of the water intake tank is made of an impermeable material such as a reinforced concrete layer 8 above the lowest groundwater level to prevent intrusion of wastewater that has not been sufficiently purified.

Also, for the same reason, the side walls of the water intake tank should be at least 30 skins higher than the ground surface. Water is pumped from the water intake tank by a suitable water pumping mechanism, such as a water pump 9, and is sent to a water storage tank or the like.

It is preferable that the water pump be of an automatic level switch type, and the water intake point at the tip should be made of mesh-like water permeable material (
If necessary, a chlorine sterilization chamber 11 is provided.

Furthermore, a lid 12 can be attached to the top end of the water intake tank exposed to the ground surface to improve the water pumping capacity. Although the method and apparatus of the present invention can be applied to factories in various industries, the effects are particularly significant when applied to oil refineries, petrochemical factories, steel factories, and the like. That is, since the premises of refineries and the like are regulated to have 10% or more of them as green belts, a large amount of money is required for the accompanying water sprinkling equipment construction. By employing the method and apparatus of the present invention, this water sprinkling equipment becomes unnecessary or can be reduced in size. Similarly, rainwater drainage construction costs can also be reduced. Note that either wastewater or rainwater may be collected in consideration of the size of the factory site, especially the area where no product leakage occurs, and the amount of water required. Since the water quality required for industrial water is almost the same as for drinking water, sufficient consideration is required when collecting and using non-oil-containing wastewater or rainwater.

In the present invention, since the lower layer of the permeable ground surface is a soil layer, drainage water and rainwater are naturally purified as they move downward. Furthermore, when this water enters the water intake tank, it is also purified by earth and sand, so the water pumped from the water intake tank can be fully used as water for mining.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the method and apparatus of the present invention,
FIG. 2 is a detailed explanatory diagram of the water intake tank. 2... Water collection pond, 3... Water intake tank, 4...
... Sediment layer, 5 ... Permeable layer, 13 ...
・Water intake pipe. Traditional 1 diagram key 2 diagram

Claims (1)

[Scope of Claims] 1. The ground surface of the non-leak area of the factory premises is made of a water-permeable material as a water-permeable layer to allow drainage and rainwater to pass through, and the lower layer of the water-permeable layer is made of earth and sand with a low effective water content. Wastewater and rainwater are passed through the soil layer and purified by the self-cleaning action of soil microorganisms, and then guided to a collection pond whose side walls and bottom are made of impermeable material. The water thus collected can be introduced into a water intake tank whose side walls and bottom are made of a water-permeable material, and the water thus collected can be pumped onto the ground surface by a pumping mechanism installed in the water intake tank. A method for collecting wastewater and rainwater, characterized by: 2 A water collection pond is formed by excavating a non-leak area on the factory premises and the bottom and side walls are made of impermeable material, and part of the bottom and side walls of the water collection pond are made of water permeable material. At the same time, a water intake tank is provided, and the outside of the water intake tank is filled with earth and sand with a low effective water content to form a soil layer, and a water permeable layer is formed from above the earth and sand layer to the ground surface using a water permeable material. 1. A drainage and rainwater recovery device, characterized in that the water intake tank is equipped with pumping means for guiding the water in the water intake tank onto the ground surface.