JPH1147507A - Oil-from-water separation apparatus and oil-from-water separation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil-from-water separation apparatus which can reliably carry out oil-from-water separation of wastewater and easily take out and treat separated oil and fat components if necessary. SOLUTION: This apparatus comprises a first container 1 having a flow inlet 1a and a second container 21 having a flow outlet formed at the lower position than the flow inlet and the first container and the second containers are mutually communicated through only a route 22 formed at the position at a prescribed distance from the flow outlet. Wastewater to be treated for oil-from-water separation flows into the inside of the first container containing lingering water with the surface level equivalent to the flow outlet through the flow inlet in the pressurized condition and the oil and fat components contained in the wastewater are floated and separated in the first container without practically reaching the second container through the route 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil / water separation apparatus and an oil / water separation method, and more particularly to an apparatus and a method for separating oil and fat components contained in wastewater.

[0002]

2. Description of the Related Art Heretofore, as typical examples of an apparatus for separating water and oil components, grease interceptors or grease straps installed in restaurants and other food-related establishments, parking lots and gas stations have been known. There are gasoline interceptors, or gasoline traps, installed in oil and other oil-related establishments. Hereinafter, the grease interceptor and the gasoline interceptor are collectively referred to as “grease trap”. The grease trap is a drain pit type device provided with a drain trap for preventing odor from flowing backward from an external drain pipe. In the drainage pit of the grease trap, a pair of blocking plates for blocking the flow of the inflowing drainage is arranged. The pair of blocking plates extend to the vicinity of the bottom of the drain pit, and the drained water passes between the pair of blocking plates and the bottom of the drain pit. And the first blocking plate and the second
The oil component contained in the drainage floats and separates when passing through the second blocking plate, and the flow of the separated oil component is blocked by the second blocking plate. On the other hand, the waste water from which the fat component has been separated passes between the second blocking plate and the bottom of the drain pit, and is discharged to an external drain pipe via a drain trap. The grease trap is an open-to-atmosphere type and is a natural flow-down type that does not involve the pumping of drainage by a power source, and thus requires a pit capacity proportional to the volume of drainage to be treated.

[0003]

The required capacity of the grease trap drain pit is typically determined based on the residence time of the drain. The residence time of the wastewater is predicted and determined based on the inflow amount of the wastewater per hour. However, the amount of inflow of wastewater at food-related establishments such as restaurants is not average, and the amount of inflow of wastewater generally increases instantaneously. Then, when the inflow amount of the wastewater sharply increases (such as at the time of washing dishes), the fat and oil component is most frequently mixed into the wastewater. Therefore, the residence time of the wastewater when the inflow of the wastewater increases drastically becomes very short, and the wastewater containing the fat and oil component flows out through the external drain pipe without being sufficiently prevented from separating the fat and oil component. Become. To avoid this, a capacity of 5 to 10 times or more of the pit capacity currently selected from the standardized products is required, but this is practically impossible.

[0004] Further, as described above, in the grease strap, the oil and fat component floats up between the pair of blocking plates, so that the waste water is separated into oil and water. However,
Since a good method for removing the separated fats and oils components from the grease trap has not been developed yet, the old style still uses a ladle for scooping. As described above, since the grease trap is of the natural flow type, the surface where the floating oil and fat component stays must be lower than the floor surface or the ground surface by 50 cm or more. Therefore,
The scooping operation with a ladle is a manual operation that requires a great deal of time and effort. At the present time, no clear guideline has been given for the method of disposing of the fats and oils components collected by the ladle.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to reliably perform separation of oil and water in wastewater and to separate and dispose of separated oil and fat components as required. It is an object to provide an apparatus and an oil-water separation method.

[0006]

According to the present invention, a first container having an inflow port is provided.
A second container having an outlet formed at a position lower than the formation position of the inflow port, wherein the first container and the second container are separated by a predetermined distance from the formation position of the outflow port. It communicated with each other only through a path formed at a low position, and flowed into the inside of the first container containing stagnant water having a water level corresponding to the outlet under a predetermined pressure state through the inlet. The oil and fat component contained in the wastewater to be separated into oil and water floats on the surface of the stagnant water in the first container and is separated without substantially reaching the second container via the path. An oil-water separation device is provided.

According to a preferred aspect of the present invention, the oil-water separator has a common container in which both the inlet and the outlet are formed, and a bottom portion of the common container is provided inside the common container. Is formed, a region closer to the inflow port than the partition wall forms the first container, and a region closer to the outflow port than the partition wall forms the second container, The space formed between the partition and the bottom of the common container forms the path. Alternatively, the oil-water separation device includes a bottom portion of the first container and the second portion.
And a communication pipe connected to a bottom portion of the container, and the communication pipe forms the path.

According to another aspect of the present invention, the first container on the inflow side and the second container on the outflow side, which are in communication with each other only through a predetermined path formed in the bottom portion, are provided. Forming a stagnant water having a water level corresponding to the outlet of the second container, from the inlet of the first container formed at a position higher than the outlet of the second container toward the stagnant water; The waste water to be separated into oil and water at a predetermined pressure,
The fat component contained in the drainage flowing into the first container is supplied to the second container via the predetermined path formed at a position lower than the outlet of the second container by a predetermined distance. An oil-water separation method is provided, wherein the oil-water separation method floats and separates on the surface of the stagnant water in the first container without substantially reaching. According to a preferred aspect of the method, the first container formed at a position slightly lower than the outlet of the second container in a state where the inflow of the wastewater into the first container is stopped. Is opened, and the fat component floated and separated on the surface of the retained water is taken out of the first container and stored in a third container. In this case, take out from the first container and remove the third
It is preferable that the fat component is changed into an emulsion liquid in the third container by adding a decomposition treatment agent to the fat component contained in the container.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, in the present invention, stagnant water is formed in a first vessel on the inflow side and a second vessel on the outflow side connected via a communication path, Drainage to be separated into oil and water is caused to flow from the inlet of the container toward the retained water at a predetermined pressure. Here, the inlet of the first container is formed at a position higher than the outlet of the second container, and the communication path is formed at a position lower than the outlet by a predetermined distance. Therefore, the stagnant water formed in the first container has a predetermined stationary water level corresponding to the outlet of the second container.

[0010] As described above, the conventional grease trap is of a natural flow-down type, so that the residence time of the drainage when the inflow of the drainage increases sharply becomes very short, and the oil and fat components can be sufficiently prevented from being separated. Did not. However, in the oil-water separation device and the oil-water separation method of the present invention, the wastewater that has flowed in at a predetermined pressure state is caused to rush into the stagnant water having a predetermined depth. As a result, the fat and oil component having a small specific gravity contained in the waste water cannot reach the second container from the stagnant water surface via the communication path formed at a predetermined depth position, and the stagnant water in the first container Ascends above the surface of the water. Thus, in the present invention, the fat component contained in the wastewater can be reliably separated.

According to the present invention, the stagnant water is opened by opening the outlet of the first container formed at a position slightly lower than the outlet while the inflow of drainage into the first container is stopped. Only the fat component floating and separated on the water surface can be taken out of the first container and stored in the third container. That is, only the separated fats and oils components can be moved to another container by a simple operation without power using the power source of opening the outlet formed in the first container without using a power source. The components can be disposed of in various ways. In this case, a method is preferable in which the fat and oil component is converted into an emulsion liquid by adding an appropriate decomposition treatment agent to the fat and oil component contained in the third container. The emulsion liquid obtained by this disposal method is easily dissolved in water, and has no effect on the ecosystem even if it is discharged as wastewater as it is.

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a view schematically showing a configuration of an oil-water separator according to a first embodiment of the present invention. The oil-water separation device in FIG. 1 includes a container 1 formed in, for example, a cylindrical shape having a bottom (a bottomed cylindrical shape), and a lid 2 for closing an upper end opening of the container 1. An opening 1 a as an inflow port is formed in the upper part of the side wall of the container 1, and one end of the inflow pipe 3 protrudes into the container 1 via the inflow port 1 a. Container 1
An opening 1b as an outlet is formed at a position lower than the inlet 1a in the upper part of the side wall of the, and the outlet pipe 4 is connected to the outlet 1b.

Further, a partition 5 extending to the vicinity of the bottom 1c is formed inside the container 1, and a region closer to the inlet 1a than the partition 5, that is, an inflow region, and an outlet 1 closer than the partition 5 are formed.
The region on the b side, that is, the outflow region, is in communication with the partition wall 5 and the bottom 1 c of the container 1. In other words, the inflow region forms the first container, the outflow region forms the second container, and the first container and the second container are the space between the partition wall 5 and the bottom 1c of the container 1. Just communicate through. In the container 1, the partition wall 5 flows from the inflow pipe 3 and the container 1.
The filtration filter 6 is disposed so as to be immersed in the wastewater flowing out of the outflow pipe 4 through the space between the bottom 1c. Specifically, the filtration filter 6 is formed in the shape of a cylinder with a bottom like the container 1, and the inside of the container 1 is larger than the outlet 1 b so that the bottom 6 a of the filtration filter 6 and the bottom 1 c of the container 1 face each other. It is suspended on a projection 7 formed at a slightly lower position.

Further, an opening 1d as an outlet is formed at a position slightly lower than the outlet 1b in the upper part of the side wall of the inflow area of the container 1. Specifically, the lowest point of the outlet 1d is lower than the lowest point of the outlet 1b by, for example, about 2 mm. One end of an oil / fat extraction pipe 8 is connected to the outlet 1d, and the other end of the oil / fat extraction pipe 8 is connected to an upper part of an oil / fat component container 9. An extraction valve 8 a is provided in the path of the extraction pipe 8. An oil / fat component discharge pipe 10 is connected to the bottom of the dedicated container 9, and a discharge valve 10 a is provided in a path of the discharge pipe 10.

In the first embodiment, the discharge valve 8a of the oil / fat extraction pipe 8 and the discharge valve 10 of the oil / fat discharge pipe 10
After closing both a, water is introduced into the container 1 through, for example, the inflow pipe 3 or the upper end opening of the container. The introduction of water into the container 1 is continued until water starts flowing out of the outflow pipe 4. In this way, in the inflow area and the outflow area in the container 1, stagnant water having a stationary water level 11 corresponding to the height of the outlet 1b (strictly, the height of the lowest point of the outlet 1b) is formed. In this state, the wastewater to be separated into oil and water, which has been pumped under a predetermined pressure state through the inflow pipe 3, flows into the container 1, and the discharged wastewater rushes into the stagnant water in the container 1. At this time, since the fat and oil component contained in the inflowing wastewater has a low specific gravity, after once entering the stagnant water, it floats without reaching the bottom surface 6a of the filtration filter 6 and forms the fat and oil component layer 12 on the water surface of the stagnant water. I do.

On the other hand, the drainage portion of the inflowing wastewater except for the oil and fat component penetrates deeply into the retained water and exerts a pressure action on the retained water. As a result, the retained water (including the inflow wastewater) passes through the filtration filter 6 so as to maintain the stationary water level 11 of the retained water. At this time, the waste contained in the wastewater is captured on the bottom and side surfaces of the filter 6. Filtration filter 6
Passes through the space between the partition wall 5 and the bottom 1c of the container 1 and reaches the outflow area, and after flowing up the outflow area, flows out through the outflow pipe 4.

Thus, in the container 1, the inflowed waste water is separated into oil and water, and the separated oil component layer 12 is formed on the surface of the retained water. In order to take out the separated fat and oil component layer 12 from the container 1 and dispose it, the flow of drainage into the container 1 is stopped. Then, the lid 2 is removed, and a small amount of water is gently poured from above the oil component layer 12 in case that the actual water level in the container 1 is different from the predetermined still water level 11 due to some factor. At this time, excess water exceeding the stationary water level 11 flows out through the outflow pipe 4. Since the fat and oil component is generally soiled, the static water level 11
Although it is difficult to visually confirm the securing of water, it is necessary to confirm the outflow of water from the outflow pipe 4 so that the actual water level of the stagnant water in the container 1 matches the predetermined stationary water level 11. Can be.

After the stationary water level of the stagnant water has been stabilized by the above-described operation, the take-out valve 8a is opened so that the container 1
The oil and fat component separated inside is taken out and moved into a dedicated container 9 via a piping 8. As described above, the lowest point of the outlet 1d for taking out the separated fat component is slightly (for example, about 2 mm) lower than the position of the lowest point of the outlet 1b, that is, the position of the still water level 11. . Therefore, when the take-off valve 8a is opened, the separated fat component starts to move, and when the movement of the fat component is completed, a part of the water in the surface layer of the stagnant water in contact with the fat component layer is induced by the movement of the fat component. Move. However, outlet 1d
Most of the stagnant water from the lowest point of
It does not move due to the effects of the gravity of water and the surface tension of water. That is, without using a power source, only the oil and fat component separated in the container 1 is taken out of the container 1 by a simple operation without power, and the dedicated container 9 is used.
Can be moved inside.

The fat and oil component taken out of the container 1 and stored in the special container 9 can be disposed (processed) by various methods. First, when the fat component is a mineral fat or a large amount of edible fat, the discharge valve 10a is opened and taken out from the dedicated container 9 to another movable container via the discharge pipe 10, It can be incinerated in in-house incinerators or incinerators of specialized processors. In addition, when the amount of the fat component is large, it is possible to treat the oil at a reprocessing plant.

Next, if the fat component is an edible fat and the amount is small, it is difficult to dispose of the component even if it is separated by oil and water. In the first embodiment, the exclusive container 9
The fats and oils component taken out of the container is disposed of in the container by decomposition treatment. This disposal method is a modified application of a method for producing soap using edible waste oil as a raw material. As is generally known, soap can be easily prepared by adding an appropriate amount of caustic soda to edible waste oil. Of course, in order to commercialize the soap thus produced, processing steps such as filtration, decolorization, heating, stirring, cooling, pressing, drying, and pulverization of waste oil are required, and a considerable processing time is required. However, in the case of wastewater treatment, the purpose can be achieved if the fat component separated from the wastewater is decomposed. In the case of wastewater treatment, what is required is that the decomposition treatment is simple, the handling of additives (decomposition treatment agents) is safe,
The wastewater after the decomposition treatment is harmless to humans and animals and is safe for the environment.

Since caustic soda used as an additive to edible waste oil is specified as a powerful drug, its handling involves danger and troublesomeness. In the first embodiment, as an additive that satisfies the above-described conditions, for example, a decomposition treatment agent containing a fatty acid sodium or a silicic acid as a main component (commercial product manufactured by Environmental Service Co., Ltd .: okyu Akyu cleaner) is used. . That is, in the first embodiment, an appropriate amount of a decomposition treatment agent is added to the dedicated container 9 containing the oil and fat component taken out of the container 1, and the mixture is stirred with an appropriate rod-shaped member as needed. Since the fat and oil component in the dedicated container 9 is almost completely separated from water, the added decomposition treating agent reliably reacts only with the fat and oil component, and the fat and oil component is immediately decomposed to be a milky liquid.

Since the emulsion liquid obtained by the decomposition treatment in the dedicated container 9 is easily dissolved in water, even if it is discharged as wastewater as it is, it has no effect on the ecosystem. In particular, it has been confirmed that sewage treatment and septic tanks have no effect on degrading bacteria. Further, the emulsion liquid obtained by the decomposition treatment has a certain washing ability as a detergent. Therefore, if the milky liquid is reused as a cleaning aid for containers and pipes of the apparatus, the workability and economic efficiency of the apparatus can be improved.

FIG. 2 is a diagram schematically showing a configuration of an oil / water separation device according to a second embodiment of the present invention. The second embodiment has a configuration similar to that of the first embodiment. However,
In the second embodiment, the partition 5 of the container 1 is removed and the container 1 is removed.
This is basically different from the first embodiment only in that a container 21 communicating with the first embodiment is provided, and the outflow pipe 4 is connected to this container 21. Therefore, in FIG. 2, elements having the same functions as those of the first embodiment are denoted by the same reference numerals as those in FIG. Hereinafter, the second embodiment will be described focusing on the differences from the first embodiment.

The oil / water separator of FIG. 2 includes a container 21 formed in a closed cylindrical shape having, for example, a bottom portion and an upper end portion. Inlet 1 of container 1 at the upper part of the side wall of container 21
An outlet 1b is formed at a position lower than "a" (at substantially the same height as the position where the outlet 1b is formed in the first embodiment), and the outlet pipe 4 is connected to the outlet 1b. Further, a communication pipe 22 is connected between the bottom portion of the container 1 and the bottom portion of the container 21, and the communication pipe 2 is connected between the container 1 and the container 21.
It communicates via two. In other words, the inflow region in the container 1 forms the first container, the outflow region in the container 21 forms the second container, and the first container and the second container only connect with the communication pipe 22. Communicated through. Other configurations are the same as those of the first embodiment, and a duplicate description will be omitted.

In the second embodiment as well, the outlet valve 8a and the discharge valve 10a are both closed, and water is introduced into the vessel 1 through the inflow pipe 3 so that the stationary water level corresponding to the height of the outflow port 1b is obtained. A stagnant water having 11 is formed. In this state, when the waste water to be separated into oil and water is pumped under a predetermined pressure state through the inflow pipe 3, the discharged waste water is separated into oil and water inside the container 1 as in the first embodiment.
The oil component layer 12 is formed on the surface of the retained water. The drainage portion of the inflow wastewater excluding the oil component rushes deeply into the stagnant water to exert a pressure action, and the stagnant water (including the inflow effluent) reaches the container 21 via the filtration filter 6 and the communication pipe 22. The water that has flowed into the container 21 flows out through the outflow pipe 4 after ascending the outflow region in the container 21. Hereinafter, from the container 1 of the separated oil component layer 12 to the dedicated container 9
The removal and disposal thereof are the same as in the first embodiment, and a duplicate description will be omitted.

In each of the above-described embodiments, the present invention has been described based on a configuration in which waste water is pushed into the container via the inflow pipe 3. The wastewater can also be guided into the container via 3.

[0027]

As described above, according to the oil-water separation apparatus and the oil-water separation method of the present invention, the wastewater that has flowed in at a predetermined pressure state enters the stagnant water having a predetermined depth and is included in the wastewater. The fat and oil component having a low specific gravity cannot reach the second container from the stagnant water surface via the communication path formed at a predetermined depth position, and floats on the stagnant water surface in the first container and is reliably separated. Is done. Further, by a simple operation without power by opening the outlet formed in the first container, only the separated fat and oil component can be moved to another container, and the separated fat and oil component can be disposed of by various methods. It is possible to

[Brief description of the drawings]

FIG. 1 is a view schematically showing a configuration of an oil-water separator according to a first embodiment of the present invention.

FIG. 2 is a view schematically showing a configuration of an oil-water separation device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 1a Inflow port 1b Outflow port 1c Bottom 1d Outlet 2 Cover 3 Inflow pipe 4 Outflow pipe 5 Partition wall 6 Filtration filter 7 Protrusion part 8 Oil and fat component extraction pipe 8a Extraction valve 9 Dedicated container for oil and fat components 10 Drain pipe 10a Discharge valve 11 Retention Water level of water 12 Oil and fat component layer 21 Container 22 Communication pipe

Claims (9)

[Claims] A first container having an inlet, and a second container having an outlet formed at a position lower than a position where the inlet is formed, wherein the first container and the second container are provided. And the container communicates with each other only through a path formed at a position lower by a predetermined distance than the formation position of the outlet, and the first container containing stagnant water having a water level corresponding to the outlet. The oil component contained in the wastewater to be separated into oil and water which has flowed into the inside at a predetermined pressure state through the inflow port does not substantially reach the second container via the path in the first container. Wherein the accumulated water floats on the surface of water and is separated therefrom. 2. The oil-water separation device has a common container in which both the inflow port and the outflow port are formed. Inside the common container, a partition extending to near the bottom of the common container is provided. The region on the inflow side with respect to the partition forms the first container, and the region on the outflow side with respect to the partition is the second container.
The oil-water separation device according to claim 1, wherein the container is formed, and a space formed between the partition and the bottom of the common container forms the path. 3. The oil-water separator has a communication pipe connected between a bottom portion of the first container and a bottom portion of the second container, and the communication pipe forms the path. The oil-water separation device according to claim 1, wherein: 4. The oil-water separation device includes a take-out and storing means for taking out and storing, from the first container, an oil and fat component floated and separated on the surface of the stagnant water in the first container. The oil-water separation device according to any one of claims 1 to 3, wherein: 5. The discharge container, wherein a discharge pipe having one end connected to the first container at a position slightly lower than a position where the outlet is formed, and a discharge pipe having one end connected to the other end of the discharge pipe. 3. The container according to claim 3, further comprising a discharge valve provided in a path of the discharge pipe.
8. The oil-water separation device according to 1. 6. The oil-water separator according to claim 5, wherein a discharge pipe is connected to a bottom of the third container, and a discharge valve is provided in a path of the discharge pipe. 7. A first container on an inflow side and a second container on an outflow side which are connected to each other only through a predetermined path formed in a bottom portion.
And a stagnant water having a water level corresponding to an outlet of the second container, and an inlet of the first container formed at a position higher than the outlet of the second container. The wastewater to be separated into oil and water flows into the stagnant water at a predetermined pressure state, and the oil and fat component contained in the wastewater flowing into the first container is more predetermined than the outflow port of the second container. The first container is separated by floating on the surface of the accumulated water in the first container without substantially reaching the second container via the predetermined path formed at a position lower by a distance. Oil-water separation method. 8. An outlet for the first container formed at a position slightly lower than the outlet of the second container in a state where the inflow of the drainage to the first container is stopped. The oil / water separation method according to claim 7, wherein the oil / fat component which is opened and floated and separated on the surface of the retained water is taken out of the first container and stored in a third container. 9. The method according to claim 9, wherein the third container is removed from the first container and
The oil / water separation according to claim 8, wherein the fat / oil component is changed into an emulsion liquid in the third container by adding a decomposition treatment agent to the fat / oil component contained in the container. Method.