JP2002186965A - Industrial waste water treatment installation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control oil contamination of a filtering tank to maintain a purifying function for a long time. SOLUTION: Floating oil clots and solid particles, or the like, and oil, or the like, mixed in waste water in a first sedimentation tank 3 are mostly absorbed and removed by passing through a first 10 and a second 14 filter media made of sawdust. The flow into a second sedimentation tank 4 is scattered by passing through the second filter medium 14. The flow into a third 5 and a fourth 6 sedimentation tanks slowly wells up from each of outlets 18, 21 of a first 16 and a second 19 conduit tubes. As a result, separated oil floating on the waste water surface in the second 4, the third 5, and the fourth 6 sedimentation tank is not drawn into the bottom and thus the waste water flows into a fourth sedimentation tank 6 after removal of the oil in the second 4 and the third 5 sedimentation tanks. The waste water flows into a filter tank 7 after the oil is further removed in the fourth sedimentation tank 6. The waste water containing very little oil flows through a third filtering medium 29 made of sawdust and thereafter through a filter layer 26 and is thus purified and discharged through an outlet 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plant wastewater treatment apparatus, and more particularly, to a plant wastewater containing oil, which is sequentially introduced into a plurality of sedimentation tanks and filtration tanks and passed therethrough to remove oil and purify the same. The present invention relates to a factory wastewater treatment device.

[0002]

2. Description of the Related Art In a car dismantling factory, a scrap factory, a gas station, etc., oil such as engine oil, brake oil, gasoline, etc. often leaks to floors, premises, etc. Washed and washed off, or washed off by rain. These washing water, rainwater, etc. are discharged into rivers and the sea from drains in and around the premises, but are discharged directly to rivers and the sea because they are wastewater containing a large amount of oil, that is, factory wastewater. This destructs the environment and requires that oil be removed and cleaned before being discharged.

[0003] Therefore, various types of factory wastewater treatment apparatuses have been employed in which factory wastewater is sequentially introduced into and passed through a plurality of sedimentation tanks and filtration tanks to remove and clean oil. For example, in a car dismantling plant, three sedimentation tanks and one filtration tank are arranged in series, and an intermediate part of the settling tank on the upstream side and an upper part of the settling tank on the downstream side are formed by an inverted L-shaped pipe. And an intermediate wastewater treatment apparatus in which an intermediate part of the final settling tank and an upper part of the filtration tank are communicated by a fountain line composed of an inverted L-shaped pipe. According to this factory wastewater treatment apparatus, wastewater flowing from drainage dwells temporarily in each sedimentation tank, and oil separated during that time floats on the water surface, and oil and oil adhering to solid particles such as sand, stones, and trash. Lumps precipitate and most of the oil is removed. The wastewater introduced from the final sedimentation tank into the filtration tank is removed of oil while passing through a filter medium layer composed of a sand layer, a stone layer, etc., and is purified and drained.

[0004]

However, the conventional factory wastewater treatment apparatus has a problem that a large amount of oil adheres to the filter medium layer in a short period of time, and the cleaning function deteriorates early. After examining the cause, the following was clarified. Since the first sedimentation tank is connected to the middle sedimentation tank by a water conduit composed of an inverted L-shaped pipe, the amount of oil flowing into the downstream sedimentation tank, in other words, the amount of oil flowing into the filtration tank, is suppressed. hard. In other words, the amount of oil contained in the wastewater that flows in from the drainage ditch is gradually reduced because the oil separated during the temporary stagnation in each settling tank floats on the water surface, and the oil and oil lumps attached to the solid particles settle. And flows into the filtration tank. By the way, it is desirable that the wastewater flowing into the filtration tank contain as little oil as possible.However, oil adhering to solid particles loosely settling or floating in the final settling tank, oil lumps, unseparated oil, etc. Is mixed. These oils depend on the amount of oil in the wastewater flowing from the middle settling tank, and the amount of oil in the wastewater from the middle settling tank depends on the amount of oil in the wastewater flowing from the first settling tank. In the first settling tank, most of the oil in the wastewater separates and floats on the water surface, and heavy oils and oil lumps attached to the solid particles sink and are separated from the wastewater. However, the wastewater contains a considerable amount of oil adhering to loosely settled or suspended solid particles and mixed oil, and these oils flow into the intermediate sedimentation tank from the water conduit. The outlet of the water conduit connecting each settling tank faces horizontally,
Since wastewater flows toward the partition between the opposing settling tanks,
Particularly when the inflow of wastewater is large, a horizontal rotating flow is generated, thereby generating a vortex. Due to this vortex, the oil floating on the water surface is drawn to the bottom and flows from the sedimentation tank or the fountain line downstream from the water conduit to the filtration tank. Further, since the outlet of the upstream water conduit and the inlet of the downstream water conduit or fountain line are on the center line of each sedimentation tank, it is easily affected by the vortex, and each sedimentation tank or filtration tank has Oil floating on the surface of the settling tank on the upstream side is drawn into the incoming wastewater. Since the outlet of the fountain line is set vertically and at a position slightly protruding toward the filtration tank, the inflowing wastewater does not spread over the entire surface of the filter medium layer. Therefore, the wastewater flows down at a local portion of the filter medium layer, and oil adheres intensively to the filter medium layer at that portion, and the function of the entire filter medium layer is reduced at an early stage.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to suppress early contamination of a filter medium layer of a filtration tank by oil contained in factory wastewater, and to reduce the length of factory wastewater. It is an object of the present invention to provide a plant wastewater treatment device that can be cleaned over a period of time.

[0006]

In order to solve the above-mentioned problems, the present invention focuses on the fact that sawdust is excellent in adsorbing oil, and manufactures an ogafilter for storing and holding sawdust in a fluid state. By arranging the oga filter between the first sedimentation tank and the next sedimentation tank, the inflow of oil into the next sedimentation tank and, consequently, the inflow into the filtration tank are suppressed. A filter medium made of an oga filter is placed above the filter medium layer of the filter tank, and the oil introduced into the filter tank is first adsorbed and removed by the filter medium, thereby suppressing early contamination of the filter medium layer. By arranging the fountain line near the center of the filter tank and setting the outlet wide, the inflowing wastewater is dispersed over a wide range, and local contamination of the filter medium layer is suppressed. In addition, by setting the outlet of the water conduit communicating the upstream settling tank and the downstream sedimentation tank upward and wider than the cross-sectional area of the water conduit, oil floating on the water surface of the downstream sedimentation tank is drawn to the bottom. It's not like that.

That is, the present invention relates to a factory wastewater treatment apparatus for removing and purifying oil by removing and purifying oil from an industrial wastewater containing oil in a plurality of sedimentation tanks and filtration tanks. A flowing water channel is provided so as to communicate with each upper part of the sedimentation tank and the next sedimentation tank, and a filter medium made of an OG filter is detachably disposed so as to cover an inlet of the flowing water channel, and the OG filter is placed in a coarse cloth bag. The sawdust is stored in the eighth part, and the bag is formed in a flat plate shape by connecting the front and back of the bag at a plurality of upper and lower places so that the sawdust is not biased up and down, and a wavebreak plate is provided at an interval upstream of the filter medium A wavebreak plate extends vertically from the upper end of the first settling tank to the vicinity of the lower end of the filter medium. In addition, it is preferable that the lower end of the wave preventing plate is located above the lower end of the filter medium, and a plurality of water holes are formed on the lower end side, so that the upward flow is decelerated by the flow through the water holes. Also,
It is preferable that a filter medium made of an OG filter is detachably disposed so as to cover the outlet of the water channel, and the water channel is used as a filtration tank and a sedimentation tank.

Further, according to the present invention, a water conduit is provided so as to communicate an intermediate portion of the upstream sedimentation tank and an upper part of the downstream sedimentation tank, and an outlet of the water conduit is upward below the stop water level. And the opening area of the outlet is set to be larger than the cross-sectional area of the water conduit. A fountain pipe is provided so as to communicate the middle part of the final settling tank with the upper part of the filtration tank, and the fountain pipe extends horizontally to the center in the filtration tank, leaving a bottom from the tip to the base. An outlet opening upward is formed, and a plurality of flow holes are formed at the bottom. In the filtration tank, a filter medium consisting of an oga filter is detachably mounted on the upper part of the filter medium layer. They are connected to form a flat plate.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. 1 and 2 are conceptual explanatory diagrams of an embodiment of the present invention, and FIGS. 3 and 4 are conceptual explanatory diagrams of a filter medium in the embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a factory wastewater treatment device, 2 denotes a drainage ditch provided around a factory site, and 3.
Denotes a first settling tank, 4 denotes a second settling tank, 5 denotes a third settling tank, 6 denotes a fourth settling tank, and 7 denotes a filtration tank. In the following, upstream and downstream are expressions based on the flow direction of the wastewater, and the left side in FIG. 1 is referred to as upstream and the right side is referred to as downstream. Stop water level H
Means each tank 3 when waste water is not flowing from the drain 2
The water levels of 4, 5, 6, and 7 are meant.

The first sedimentation tank 3 is a box-shaped water tank having an open upper side. The first sedimentation tank 3 is provided with a drain groove 2 near an upper corner of one side wall, and is a sand basin for temporarily storing wastewater flowing from the drain groove 2. . In the first settling tank 3, heavy solid particles in the wastewater,
Oil lumps and the like settle to the bottom, most of the oil separates and floats on the water surface, light solid particles, oil lumps and the like float or loosely settle, and unseparated oil is mixed into the wastewater. At a central upper portion of the partition wall between the first settling tank 3 and the second settling tank 4, a water passage 9 having a rectangular cross section is provided so as to protrude horizontally from the first settling tank 3 into the second settling tank 4. This water channel 9 is the first 9
A first filter medium 10 is arranged along the opening on the settling tank 3 side, and the second filter medium 1 is arranged along an opening on the second settling tank 4 side which is the outlet 9b.
A space is formed along each side wall of the second settling tank 4. This space forms a stagnation, and the first filter medium 10
It is also a filtration / precipitation tank in which fine solid particles, oil lumps and the like in the wastewater passing through are filtered and precipitated.

As shown in FIG. 3 and FIG. 4, the first filter medium 10 and the second filter medium 14 store sawdust in an open cloth bag at an eighth minute, and a plurality of sawdust are arranged so that the sawdust is not deviated vertically. The bag is formed of a flat plate-shaped ogafilter by intermittently connecting the front and back of the bag with a fastening thread 10a. The coarse cloth only needs to be of such a degree that the sawdust is hard to spill, and a gauze made of a coarse and soft cotton cloth is preferable. The sawdust is stored in the bag for the eighth minute, and the sawdust easily flows in the bag due to the wastewater passing therethrough, so that the oil in the wastewater is adsorbed and removed well, and the wastewater passes well without clogging. The first filter medium 10 is detachably mounted from above on a first filter medium mounting frame 11 mounted along the inlet 9a of the flowing water channel. Although the specific structure of the first filter medium mounting frame 11 is not shown, an upward U-shaped frame main body having a groove-shaped space around the inside is formed by combining groove-shaped members, and this frame is formed. A crimp net is stretched in one opening of the main body, and a plurality of bars are attached in the other opening in the vertical direction at intervals.
A space having a rectangular cross section formed by the frame body, the crimp net, and the bar is a space for accommodating the first filter medium 10. And
The frame main body is mounted in close contact with the inlet 9a of the flowing water channel such that the crimp net side faces upstream and the bar side faces downstream. The second filter medium 14 is removably mounted from above on a second filter medium mounting frame 15 mounted along the outlet 9b of the flowing water channel. The second filter medium mounting frame 15 has the same structure as the first filter medium mounting frame 11.

On the upstream side of the first filter medium 10, the first filter medium 10
The wave preventing plate 12 is provided in parallel at an interval. Both ends of the wave preventing plate 12 are fixed to each side wall of the first settling tank 3,
The upper end of the first settling tank 3 is vertically extended slightly above the lower end of the first filter medium 10, and a plurality of water holes 13 are formed on the lower end side. The wave preventing plate 12 partitions the upper part of the first sedimentation tank 3 into the drain groove 2 side and the first filter medium 10 side.
The wastewater flowing from the first filter medium 10 does not directly reach the first filter medium 10, but is bypassed below the wave preventing plate 12. Further, oil floating on the water surface upstream of the wave preventing plate 12 of the first settling tank 3 is stored so as not to contact the first filter medium 10. Accordingly, the first filter medium 10 is provided with a material other than oil floating on the water surface, oil adhering to precipitated oil lumps and solid particles, for example, oil adhering to oil sediment loosely or floating to solid lumps and solid particles, and wastewater. The mixed oil or the like will arrive. And the first filter medium 1
The flow of the wastewater passing through zero occurs due to the water level difference between the first sedimentation tank 3 and the second sedimentation tank 4, and at the same time, an upward flow occurs between the wave preventing plate 12 and the partition wall and the first filter medium 10. . When the speed of the upward flow is high, the sawdust of the first filter medium 10 moves upward in the bag, and the sawdust at the lower portion of the first filter medium 10 may decrease. However, simultaneously with the generation of the upward flow, a plurality of water holes 1 formed on the lower end side of the breakwater plate 12 are formed.
A flow through 3 occurs. This flow is a flow in a direction crossing the upward flow, and suppresses the speed of the upward flow. Therefore, the sawdust of the first filter medium 10 is prevented from becoming unevenly distributed in the bag, and is protected so as not to impair the function of the first filter medium 10.

The second sedimentation tank 4 is a box-shaped water tank having an upper opening, and is formed at a depth about twice as large as the first sedimentation tank 3. And an oil-attached solid particle sedimentation tank for temporarily storing wastewater flowing through the second filter medium 14. The inflowing wastewater contains minute and light solid particles, oil lumps, and unseparated oil, and some of these precipitate or separate during storage and float on the water surface. Second
Along the partition wall between the settling tank 4 and the third settling tank 5,
A first water conduit 16 is provided near the side wall of each of the settling tanks 4 and 5 away from the center. The first water conduit 16 is a pipe having a circular cross section bent at an intermediate portion so that both ends are opposite and parallel to each other, and a dish-shaped body having a protruding edge around the pipe, and communicates with one end of the pipe. The inlet 17 opens downward in the middle of the second settling tank 4,
An outlet 18 is disposed above the third settling tank 5 and opens upward below the stop water level H. In addition, one end of the tube may be expanded in a funnel shape, and this one end may be used as the outlet 18. The wastewater from the second settling tank 4 is changed to the third
The oil flows into the sedimentation tank 5, but because the outlet 18 is upward and the opening area is large, the oil flows slowly and upwards, that is, flows in such a manner that the oil gradually floats. Flows without being pulled into the bottom.

The third sedimentation tank 5 is a box-shaped water tank having an open upper part, and is a water-drainage sedimentation tank for temporarily storing wastewater flowing from the second sedimentation tank 4 through the first water conduit 16. The influent wastewater contains minute and light solid particles, oil lumps, unseparated oil, etc., and some of them settle or separate in the storage and float on the surface of the water. Precipitates. A second conduit is provided along the partition wall between the third and fourth sedimentation tanks 5 and 6, and on the side opposite to the first water conduit 16 with respect to the center of the third sedimentation tank 5, near the side wall of each of the sedimentation tanks 5, 6. Water line 1
9 are provided. The second water pipe 19 is formed by connecting an outlet member made of a dish-shaped body to a pipe bent in the same manner as the first water pipe 16, and the inlet 20 is provided at the middle of the third settling tank 5 at the first position. An outlet 21 is arranged to open downward above the inlet 17 of the water conduit, and an outlet 21 is opened above the stop water level H above the third settling tank 5 so as to open upward.

The fourth sedimentation tank 6 is a box-shaped water tank having an open upper part, and is a water-drainage sedimentation tank for temporarily storing wastewater flowing from the third sedimentation tank 5 through the second water conduit 19. A small amount of oil is contained in the inflowing wastewater, and a part thereof is precipitated in the storage as fine and light solid particles, oil lumps and water deposits, and the oil floats on the water surface. A fountain line 22 is provided along the partition wall between the fourth settling tank 6 and the filtration tank 7. Fountain line 22
Consists of a tube having a circular cross section formed by bending one end closer to 90 degrees, bending the other end closer to 90 degrees with respect to one end, and diagonally cutting off the tip of the other end. Is vertically arranged on the side opposite to the second water conduit 19 with respect to the center of the fourth settling tank 6, and the other end is connected to the fourth settling tank 6.
Are arranged horizontally so as to protrude to the center of the filtration tank 7 on the center line of the filter tank 7. That is, the inlet 23 opens downward at an intermediate portion of the fourth settling tank 6 above the outlet 20 of the second water conduit, and the outlet 24 opens upward at the top of the filtration tank 7,
The bottom of the outlet 24 is arranged along the stop water level H. As shown in FIG. 2, a plurality of flow-down holes 25 are formed at the bottom of the outlet 24 from the center of the filtration tank 7 to the vicinity of the partition wall with the fourth precipitation tank 6. When the amount of wastewater flowing from the fourth settling tank 6 is large, since the outlet 24 is formed by cutting off the end of the pipe obliquely, it diffuses around the outlet 24 and flows into the filtration tank 7. I do. When the inflow amount is small, it flows in from the tip of the downflow hole 25 and the outlet 25. The shape and structure of the outlet 25 need only be such that the wastewater does not concentrate locally on the filtration tank 7 but diffuses and flows into a wide area.

The filtration tank 7 is a box-shaped water tank having an open top. A perforated plate 30 having a perforated hole such as a punching plate is provided on the bottom side at an interval, and a stone layer is formed on the perforated plate 30. The filter medium layer 26 is formed by laminating the sand layer 27 and the sand layer 28. On the filter medium layer 26, a third filter medium 29 made of an OG filter is placed so as to cover the sand layer 28. Third
The OG filter of the filter medium 29 is basically made of the first filter medium 10.
It has the same structure as that of the first filter medium 10, but is formed thicker than that of the first filter medium 10, and the front and back of the bag are connected by a fastening thread at the center so as not to lose its shape. In FIGS. 1 and 2, reference numeral 31 denotes a lid which is detachably provided so as to cover the tanks 3, 4, 5, 6, and 7. Although the lid of the first precipitation tank 3 has a porous structure, The lids of the other tanks 4, 5, 6, and 7 are structured to prevent wastewater, solid particles, and the like from entering.

The embodiment of the present invention is configured as described above, and its operation will be described below. For example, when the wastewater treatment apparatus 1 shown in FIG. 1 and FIG. 2 is installed in a car dismantling plant, the floor, the site, etc. are washed with water or when the rain falls, the water flowing through the floor, the site, etc. And flows into the first settling tank 3. This water is factory wastewater mixed with engine oil, brake oil, oil such as gasoline, and solid particles such as sand, stone, and trash. This wastewater temporarily stays in the first sedimentation tank 3, and heavy solid particles and oil lumps settle to the bottom, most of the oil is separated and floats on the water surface, and light solid particles and oil lumps and the like float or float. Sedimentation, and some oil is mixed without separation. The oil floating on the water surface is mainly stored on the upstream side of the wave preventing plate 12. The water level in the first settling tank 3 rises due to the inflow of the wastewater, causing a difference in water level from the second settling tank 4, and the wastewater in the first settling tank 3 flows into the second settling tank 4 through the flowing water channel 9. . This wastewater is located on the downstream side of the breakwater plate 12,
It stays in the middle part or the like of the first settling tank 3 or flows therethrough, and contains light solid particles, oil lumps, mixed oil and the like floating or loosely settling.

When the wastewater flows into the second settling tank 4, it is first filtered through the first filter medium 10 to remove relatively large solid particles, oil lumps and a part of unseparated oil. That is, since the first filter medium 10 is an oga filter in which sawdust is stored in a coarse cloth bag, relatively large solid particles, oil lumps, and the like are prevented from passing through the bag, and oil adheres with fine solid particles. Some of the waste, minute oil lumps, unseparated oil, etc. adhere to sawdust. Since the sawdust flows in the bag by the flow of the wastewater, oil easily adheres to the sawdust, and a large amount of oil is removed by the first filter medium 10. The wastewater that has passed through the first filter medium 10 is
The water is filtered by the second filter medium 14 through the flowing water channel 9.
Stagnates in the spaces on both sides of the, and a part of minute solid particles, oil lumps and the like settle and are removed. When passing through the second filter medium 14, fine solid particles to which oil adheres, fine oil lumps,
A part of the unseparated oil or the like is attached and removed in substantially the same manner as in the first filter medium 10. As described above, the drain ditch 2
Most of oil, solid particles and the like are removed from the wastewater flowing from the first settling tank 3, the first filter medium 10, the flowing water channel 9 and the second filter medium 14. In particular, the first filter medium 1 includes not only relatively large solid particles and oil lumps that have not been removed until now, but also minute solid particles, oil lumps, unseparated oil, and the like.
0, a considerable amount is removed by the flowing water channel 9 and the second filter medium 14, and much more clean than before.

Although the wastewater flowing into the second settling tank 4 is purified as described above, it contains small solid particles, unseparated oil, etc., and temporarily stays there. During this time, a part of the oil separates and floats on the water surface, and a part of fine solid particles, oil lumps and the like precipitate. The water level of the second settling tank 4 rises due to the inflow of the wastewater, and a water level difference occurs between the second settling tank 5 and the first settling tank 5.
And flows into the third settling tank 5. At that time, the first settling tank 3
The wastewater flowing into the second settling tank 4 from the wastewater flows in a dispersed manner by the second filter medium 14 and does not become a jet, so that there is no vortex that draws oil floating on the water surface of the second settling tank 4 to the bottom. .
In addition, since the inlet 17 of the first headrace is arranged deviated from the center of the waterway 9, the inflow of the wastewater has little effect on the wastewater staying near the inlet 17 of the first headrace. Therefore, the wastewater flowing into the third settling tank 5 is wastewater remaining in the middle part of the second settling tank 4, that is, the wastewater after the oil is partially separated in the second settling tank 4. It has become.

The wastewater flowing into the third sedimentation tank 5 temporarily separates and partially floats on the water surface during the temporary stagnation. Precipitates and flows into the fourth sedimentation tank 6 through the second conduit 19. At this time, since the wastewater flowing from the second sedimentation tank 4 to the third sedimentation tank 5 flows into the first sewer pipe line 18 in such a manner that the wastewater slowly rises from the outlet 18, the oil floating on the surface of the third sedimentation tank 5 is removed. Do not draw in. Moreover, the inlet 20 of the second water conduit is not on the same line as the outlet 18 of the first water conduit, and is not easily affected by the flow of wastewater flowing into the third settling tank 5. As a result, the wastewater flowing into the fourth sedimentation tank 6 is obtained after the oil is partially separated in the third sedimentation tank 5, and the amount of the mixed oil is further reduced. The wastewater that has flowed into the fourth settling tank 6, as in the third settling tank 5, is partially separated from the oil during temporary stagnation and floats on the water surface, and the oil and oil adhering to the fine solid particles Lumps and the like settle, and water deposits settle and flow into the filtration tank 7 through the fountain line 22. At this time, the wastewater is supplied to the third settling tank 5
In the same manner as in the case where the wastewater flows into the third settling tank 5, it is not affected by the flow of the wastewater flowing into the fourth settling tank 6. As a result, the wastewater flowing into the filtration tank 7 is obtained after the oil has been partially separated in the fourth precipitation tank 6, and the amount of mixed oil is extremely small.

The wastewater flowing into the filter tank 7 is supplied to the third filter medium 29.
After flowing down, the water flows down the filter medium layer 26 such as the sand layer 28 and the stone layer 27 and is discharged from the water discharge channel 8. At this time, when the inflow of the wastewater is large, the outlet 24 is diffused and flows into the vicinity of the outlet 24 because the outlet 24 is formed by cutting off the end of the pipe obliquely. If the inflow is small,
5 and the outlet 24. In either case,
Since it flows over a wide range, it flows down over a wide range of the third filter medium 29 and the filter medium layer 26, whereby the oil is adsorbed and removed, and the oil is cleaned to a permissible amount. In addition, since the wastewater flows down the third filter medium 29, the sawdust flows in the bag and makes good contact with the oil in the wastewater. Most of the oil and the like are removed. The wastewater that has passed through the third filter medium 29 flows down the filter medium layer 26. Since the wastewater contains almost no oil, the adsorption of oil to the filter medium layer 26 is extremely small, and the wastewater is contaminated for a long time. Is suppressed.

It is preferable that the water level of the filter tank 7 when the waste water does not flow in is set to be approximately equal to the upper surface of the filter medium layer 26, so that the attaching and detaching operation of the third filter medium 29 can be performed smoothly and promptly. In addition, replacement work of the first filter medium 10, the second filter medium 14, and the third filter medium 29 and the respective settling tanks 3, 4, 5, 6,
Is performed after removing the lid 31. By performing these replacement work and cleaning work regularly, it is not necessary to clean the filter tank 7 and replace the filter medium layer 26 for a much longer time than before.

[0024]

According to the present invention, a filter medium made of an OG filter is provided at the inlet of a flowing water channel connecting the first settling tank and the next settling tank, and a wavebreak plate is provided upstream of the filter medium. As a result, the inflow of oil from the first settling tank to the next settling tank can be suppressed as much as possible, and thus the inflow of oil into the filtration tank can be reduced, and the function of the filter medium layer of the filtration tank can be much longer than before. It became possible to maintain. Then, the following effects are further obtained. When a water hole is provided at the lower end of the breakwater plate, do not extremely move the sawdust in the filter material upward in order to suppress the speed of the upward flow from the sedimentation tank to the filter material at the inlet of the water channel. In addition, the distribution of sawdust can be appropriately maintained and the function of the filter medium can be exhibited. If the outlet of the headrace channel that connects the upstream sedimentation tank and the downstream sedimentation tank opens upward and is wider than the cross-sectional area of the headrace channel, the wastewater from the upstream sedimentation tank is Wastewater flowing into the sedimentation tank or filtration tank further downstream does not draw oil floating on the water surface of the downstream sedimentation tank to the bottom, unlike the conventional method, because it flows into the upper part of the sedimentation tank so as to spring up slowly. Mixing of oil inside can be suppressed. If a fountain line connecting the final sedimentation tank and the filtration tank extends to the center of the filtration tank and its outlet is open upward, the wastewater from the final sedimentation tank can be used to cover a wide area of the filtration tank. Is diffused over and flows in. As a result, the filter medium layer of the filter tank is not locally concentrated and contaminated as in the related art, and the function as the filter medium layer can be maintained for a long time.
In addition, when a downflow hole is formed at the bottom of the outlet,
When the inflow amount of the wastewater is small, the wastewater can be dispersed and inflow, and local contamination of the filter medium layer can be suppressed. When a filter medium made of an OG filter is arranged above the filter medium layer of the filtration tank, the waste water flows down the filter medium layer after flowing down the filter medium, but since the filter medium is made of the OG filter, Most of the oil is adsorbed and removed by sawdust. As a result, almost no oil is contained in the wastewater that has passed through the filter medium, and the adsorption of the oil to the filter medium layer is extremely reduced, and the pollution is suppressed for a long period of time.

[Brief description of the drawings]

FIG. 1 is a conceptual explanatory diagram of an embodiment of the present invention.
It is shown in a longitudinal sectional view along the line -A.

FIG. 2 is a conceptual explanatory view of the embodiment of the present invention, which is shown in a plan view with a lid removed.

FIG. 3 is a conceptual explanatory view of a first filter medium and a second filter medium in the embodiment of the present invention, and is shown in a front view.

FIG. 4 is also shown in a side view.

[Explanation of symbols]

1 Factory wastewater treatment equipment 2 Drainage ditch
3 First settling tank 4 Second settling tank 5 Third settling tank
6 Fourth settling tank 7 Filtration tank 8 Drainage channel
9 running water channel 10 first filter medium 12 wavebreak plate
DESCRIPTION OF SYMBOLS 13 Flow water hole 14 2nd filter medium 16 1st water conduit 18 outlet of 1st water conduit 19 2nd water conduit 21 outlet of 2nd water conduit 22 fountain line 24 outlet of fountain line 25 down hole 26 filtration Filter medium layer of tank 27 Stone layer 28 Sand layer 29 Third filter medium
H Stop water level

Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) B01D 23/10 B

Claims (6)

[Claims] An industrial wastewater containing oil is separated into a plurality of settling tanks (3, 3).
4, 5 and 6) and a filter tank (7), which are successively introduced and passed to remove oil and purify the wastewater from the factory. The apparatus is a first settling tank (3) and a second settling tank (4). A water channel (9) is provided so as to communicate with each upper portion of the water channel, and a filter medium (10) made of an OG filter is detachably disposed so as to cover the inlet (9a) of the flow channel. The sawdust is stored in a coarse cloth bag for the eighth minute, and the sawdust is connected to the front and back of the bag at a plurality of upper and lower locations so that the sawdust is not biased up and down. A factory, characterized in that a wave breaker (12) is provided, and the wave breaker (12) extends vertically from the upper end of the first settling tank (3) to near the lower end of the filter medium (10). Wastewater treatment equipment. 2. The plant wastewater treatment apparatus according to claim 1, wherein the wave breaker plate (12) has a lower end located above the lower end of the filter medium (10) and a plurality of water holes (13) formed at the lower end side. . 3. The plant wastewater treatment apparatus according to claim 1, wherein a filter medium made of an OG filter is detachably disposed so as to cover an outlet of the flowing water channel. 4. The method according to claim 1, wherein the industrial wastewater containing oil is separated into a plurality of sedimentation tanks.
An industrial wastewater treatment apparatus for removing and purifying oil by sequentially introducing and passing oil through a filtration tank (4, 5, 6) and a filtration tank (7), comprising an intermediate portion and a downstream portion of an upstream settling tank (4, 5). Water conduits (16, 16) so as to communicate with the upper part of the sedimentation tanks (5, 6).
19) is provided, and an outlet (18, 21) of this water conduit is provided.
Opens upward below the stop water level (H) and exits (1
A plant wastewater treatment apparatus characterized in that the opening area of each of (8, 21) is set to be larger than the cross-sectional area of the water conduit (18, 21). 5. The method according to claim 1, wherein the industrial wastewater containing oil is separated into a plurality of settling tanks (3, 3).
4, 5 and 6) and a filter tank (7) are sequentially introduced and passed to remove oil and purify the factory wastewater treatment apparatus. The intermediate part of the final settling tank (6) and the filter tank ( A fountain pipe (22) is provided so as to communicate with the upper part of (7), and this fountain pipe (22) extends horizontally to the center in the filtration tank (7), and has a bottom portion from the tip to the base. An industrial wastewater treatment apparatus characterized by having an outlet (24) opened upward and a plurality of downflow holes (25) formed at the bottom. 6. A method according to claim 1, wherein the industrial wastewater containing oil is separated into a plurality of settling tanks (3, 3).
4, 5 and 6) and an industrial wastewater treatment apparatus for removing and purifying oil by successively introducing and passing through a filtration tank (7), wherein an oga filter is provided above a filter medium layer (26) of the filtration tank. The filter medium (29) is detachably arranged, and the saw filter stores the sawdust in the coarse cloth bag for the eighth minute, and is formed in a flat plate shape by connecting the front and back of the bag so that the sawdust is not biased. A factory wastewater treatment device characterized by the above-mentioned.