JP2004314000A - Oil-water separator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure which allows easy discharge of the mud and sand accumulated within an oil-water separator. <P>SOLUTION: The oil-water separator 10 equipped with oil-water separation compartments 11 formed with flat water discharge canals 19 along wall surfaces by attaching passage forming members 20 having channel shaped sections to partition walls 12 and utilizing their wall surfaces as portions of passages is provided. In the oil-water separation compartments 11, the passages 19 for guiding the already separated effluents 3 upward in the state of hardly overhanging into the compartments can be formed and the maintenance space for operators to enter the compartments and to carry out work can be widely assured. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for recovering oil from oil-contaminated water, also called glystop, and relates to an oil-water separation tank suitable for use in gas stations, car washes, factories using oil, and the like. Things.
[0002]
[Prior art]
2. Description of the Related Art There is known a separation tank in which wastewater mixed with oil is retained in an oil-water separation section, and oil is separated from oil and water by a difference in specific gravity with water. In many separation tanks, one separation tank is divided by a weir to provide a plurality of separation sections, and oil separated in one separation section is prevented from moving to the next section, and only water is moved. , So that the drainage with less oil content flows out.
[0003]
Among the oil-water separation tanks, the oil-water separation tank used in restaurants is relatively small. This is for the purpose of removing oil from drainage from a cooking place or the like, and is mainly provided indoors, and is installed so that a large amount of drainage such as rainwater is not mixed. On the other hand, separation tanks used in gas stations, parking lots, car washes, or factories that use oil are large. A gas station, a car wash, or the like is for preventing oil leaked to the outside or spilled outside from being discharged together with a large amount of rainwater or washing water, and the amount of wastewater to be treated becomes large.
[0004]
Small separation tanks used in restaurants generally have a total length of 1 m or less, a width of 40 cm or less, and a depth of 50 cm or less, and are made of a material that is easy to process such as FRP or stainless steel. Then, a weir (submerged weir) having an opening on the lower side is formed by a plate-shaped member attached so as to cross the inside of the tank, and the inside of the tank is divided into a plurality of separation sections. The water moves from the opening provided at the lower part of the weir to the next section, and the separated oil rises because it is light and cannot move to the next section. In addition, a removable stainless steel basket is installed in the first compartment so that solid matter such as leftovers contained in the drainage can be collected.
[0005]
On the other hand, separation tanks used in gas stations, car washing stations, factories that use oil, and the like are large in size, so they are cast in place using concrete or installed using secondary concrete products. In order to swallow and separate rainwater falling on a parking lot with oil, a large capacity is required, and the size of one section is 600 mm in inner diameter (for a square, for example, the length of one side) and 1200 mm in depth. In many cases, a configuration of about four rows in which four sections are connected in a vertical row or a cross-shaped pattern is often used. If the parking lot is large, multiple separation tanks of this size are installed. Alternatively, a larger size is installed.
[0006]
When the length of one side of the four tanks is about 2500 mm, the earth pressure applied to the side wall is large, and the configuration divided into a plurality of sections also serves as a support against the earth pressure. In particular, when the oil-water separation tank is installed in a place where an outdoor vehicle passes, a structure having high strength is advantageous because a wheel load is applied in addition to the earth pressure. When producing an oil-water separation tank with concrete, it is not economical to separate the sections with a weir having an opening at the bottom. It is troublesome to make a wall where the side wall and the lower end are not aligned, and the lower side of the side wall where large earth pressure is applied cannot be supported by the separation wall, so it is necessary to take measures such as making the side wall thicker only .
[0007]
On the other hand, in Japanese Utility Model Laid-Open No. 7-12585, a communication pipe is buried in the upper part of the partition wall of the section, the PVC pipe is extended downward, water flows in from below, and moves to the next section. are doing. This method is effective not only for oil-water separation, but also for the effect of sedimentation. That is, a lot of rainwater flows at once when it rains, so the flow velocity is large, and if an opening is provided on the lower side and multiple sections are connected, mud and oil will flow from the opening to the next section. On the other hand, if the water is drained from below in each section and flows in from above, the mud and oil can be prevented from moving due to short-circuit.
[0008]
[Patent Document 1]
Japanese Utility Model Laid-Open Publication No. Hei 7-12585
[Problems to be solved by the invention]
Therefore, it is necessary to collect the mud and sand that have settled in each separation section. However, since fine mud and sand flow in, they cannot be collected by the basket. Therefore, baskets are rarely installed, and even if a basket is installed, it is for collecting large garbage. For this reason, a separation tank used in a gas station, a car wash, a factory that uses oil, or the like, needs to enter periodically to clean mud. If the depth is about 1200 mm, the mud which has stuck together with the oil at the bottom of the separation section must be entered by an operator and taken out by a scoop.
[0010]
However, in a separation tank in which a PVC pipe is extended downward, an elbow for connecting the pipe to the communication hole of the partition wall obstructs cleaning. For example, in the separation tank 90 shown in FIG. 8, a hole 92 larger than the outer diameter of the pipe is provided in a wall 92 partitioning each separation section 91, and a cut short straight PVC pipe 94 is inserted therein. After that, fill the gap with mortar or the like. A 90-degree bent pipe 95 called an elbow is attached to the short pipe 94, and a straight pipe 96 extending to the bottom is attached below the elbow 95. As a result, of the wastewater 1 flowing into the separation section 91, the water 3 separated by the specific gravity difference from the oil component 2 moves to the next separation layer 91 via the PVC pipes 96, 95, and 94, and the oil-water separation one after another. Is performed. At the same time, sand and mud 5 accumulate at the bottom of each separation section 91.
[0011]
Therefore, it is necessary to remove the sand and mud 5, but the pipes 95 and 96 protrude to a large extent in the middle of the separation section 91, and it is difficult to secure a space for an operator. For example, if the pipe has a diameter of about 200 mm, it protrudes about 300 mm. Therefore, if it is a separation section having a cross section of about 600 mm in inner diameter, there is almost no space for a worker to work inside and it is very difficult to clean. .
[0012]
[Means for Solving the Problems]
For this reason, in the present invention, by attaching a flat member having a substantially U-shaped cross section or an arch shape to the side wall, the side wall is used as a part of the flow path, and the drainage is guided upward from below along the side wall. Configure the road. That is, in the present invention, at least one oil / water separation section for retaining the drainage to separate oil / water, an outflow hole provided above the side wall constituting the oil / water separation section, and an outflow hole along the side wall. The cross section in the horizontal direction is a substantially U-shaped or arch-shaped member having a long width direction along the side wall, and a drain passage extending from the lower side of the side wall to the outflow hole. An oil / water separation tank having a flow path forming member to be formed is provided.
[0013]
By attaching the U-shaped or arch-shaped flat flow path forming member to the wall surface, a drainage channel with very little overhang from the wall surface can be formed along the wall surface. Further, since this flow path forming member has a U-shaped cross section, it is resistant to water pressure, and even if it is a flat and thin drain path, it is not deformed by water pressure, and a drain path having a sufficient flow path cross section can be formed. Therefore, even if the cross-sectional area of the drainage channel is the same as when the pipes were laid, the drainage channel was attached to the wall, so the inside of the oil-water separation section, especially the central part, became widely usable, and workers could use it. A space for entering and maintaining can be secured.
[0014]
Furthermore, since the drainage channel is attached to the wall surface, the position where the drainage flows out of the separation section is closest to the wall surface, and the residence distance from the inflow position to the drainage position can be maximized. Therefore, the effect of improving the oil / water separation performance in each oil / water separation section is obtained.
[0015]
When forming a thin drainage channel along the side wall that separates the separation section, that is, along the partition wall, a pipe with a small aspect ratio (aspect ratio) may be specially manufactured. However, custom-built tubes are expensive and expensive to manufacture. Furthermore, if the pipe is bent and connected to the outflow hole provided in the partition wall, the arrangement becomes similar to an elbow, and it is difficult to obtain the effect of opening the area of the separation section. In order to make a hole on the side of the pipe so that it matches the outflow hole, for example, it is necessary to position the holes as viewed from the opposite side of the outflow hole, which requires multiple operators. Work.
[0016]
Further, a weir having an opening at the lower side may be provided by concrete or stainless steel in parallel with the partition wall. However, the thickness of a weir made of concrete is wasted in terms of residence distance and weight. On the other hand, if a thin plate made of stainless steel or the like is simply attached so as to divide the section in parallel with the partition wall, it is easily depressed by water pressure, and a drain having a desired shape cannot be secured.
[0017]
On the other hand, in the case of the oil / water separation tank of the present invention, since the channel forming member having a U-shaped cross section is used, accurate alignment with the outflow hole is not required. Even if the member itself is thin, the strength is high in shape. For this reason, the flow path forming member can be manufactured from a thin member such as stainless steel or a rustproof steel plate, and can be supplied at low cost. Further, since the flow path forming member forms the flow path using a part of the side wall instead of the pipe, it can be manufactured by simply processing the plate material. Therefore, the flow path forming member can be supplied at a low cost by using a highly weather-resistant material such as stainless steel, and is changed to a PVC pipe which is easily deteriorated by oil or ultraviolet rays. An almost unnecessary oil-water separation layer can be provided.
[0018]
Further, a member having a U-shaped or arch-shaped cross section is easily attached to and detached from a wall surface. For example, it is possible to bend the portion that is in close contact with the wall surface outward into a U-shape or arch shape so that the shape as a whole is close to Ω, and insert an insert for attaching the flow path forming member to the side wall. The channel forming member can be easily attached to and detached from the side wall only by being buried. Therefore, it is easy to attach to the concrete oil-water separation layer, and the work space in the compartment can be further widened by removing the flow path forming member at the time of maintenance. Also, by attaching the flow path forming member of the present invention to a concrete oil / water separation tank using a conventional PVC pipe, the oil / water separation tank of the present invention can be easily obtained.
[0019]
The flow path forming member can be attached with a cushion material interposed between the side wall and the side wall. The side wall of the oil / water separation section is not necessarily vertical or vertical, and the error can be absorbed by the cushion material. Most concrete tanks have a tapered inner surface to allow for removal from the formwork, which can be accommodated. If it is a simple taper shape, it may be able to cope with almost no cushion material.However, when the depth is about 2500 mm, there is a possibility that the oil-water separation tank may be divided into upper and lower parts, in which case, The direction of the taper may be different between the top and bottom of the side wall. On the other hand, by inserting the cushion material, the flow path forming member can be attached in a state of being substantially in contact with the side wall.
[0020]
In an oil / water separation tank having a plurality of oil / water separation sections, the outlets of each of the oil / water separation sections can be arranged in a zigzag to increase the residence distance. The flow path forming member of the present invention can be attached to the zigzag corresponding to the zigzag position of the outlet.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 shows the appearance of an oil-water separation tank 10 according to the present invention. Further, FIG. 2 shows a plan configuration of the oil-water separation tank 10 in a plan cross section. The separation tank 10 is a quadruple separation tank in which four oil / water separation sections 11 are connected in the longitudinal direction, and the structure of each separation section is shown by an enlarged cross section in FIG. The oil-water separation tank 10 is formed of on-site concrete or a prefabricated concrete block, and is used while being buried in the underground 9 of the site. In addition, a lid is installed on the upper part of the separation tank 10 with an iron plate 49 or the like, which is usually used in a closed state, and the iron plate 49 is removed when the separation section 11 is maintained.
[0022]
Each of the oil / water separation sections 11 is a concrete square having a substantially square cross section, and one side wall 12 serves as a partition wall between the adjacent oil / water separation sections 11 and drains through an outlet hole 13 formed in the partition wall 12. 1 flows in order and is separated into oil and water. That is, in the first oil / water separation section 11, the drainage 1 from a gas station or the like flows through the drain pipe 15 penetrating the front side wall 10 a of the oil / water separation tank 10. Then, the oil 2 mixed into the waste water 1 is separated by the respective oil-water separation sections 11 through the outflow holes 13, and the waste water 3, which does not contain oil, passes through the outflow pipe 13 f passing through the side wall 10 b behind the oil-water separation tank 10. The wastewater is passed through and discharged to public sewage.
[0023]
At the front (inflow side) of the partition wall 12 of the oil / water separation section 11, a plate member 20 made of stainless steel and processed to have a substantially U-shaped cross section is attached so as to cover the outflow hole 13. ing. The bent plate member 20 is a flow path forming member, and is long in the up-down direction, and has the U-shaped ends attached to the surface of the partition wall 12 so that the partition wall 12 is used as a part of the flow path. A drainage channel 19 is formed to guide drainage from the lower bottom 16 to the upper outflow hole 13 along the line 12.
[0024]
As shown in an enlarged cross section in FIG. 4, a state in which the flow path forming member 20 is attached to the partition wall 12, the length L1 in the width direction along the partition wall 12 is a length (depth or length) protruding from the partition wall 12. Projection length) L2 is sufficiently larger. Therefore, by attaching the flow path forming member 20 to the partition wall 12, as shown in FIG. 5, a flat drainage channel 19 for flowing drain water from a position near the lower bottom 16 to the upper outlet hole 13 along the partition wall 12. Is formed.
[0025]
FIG. 6A shows the flow path forming member 20 extracted. The flow path forming member 20 is formed on both sides of the U-shaped part 21 forming the drainage channel 19, and the mounting margin 22 protrudes from the U-shaped part 21 on both sides to be attached to the partition wall 12. It has a close shape. Further, two mounting holes 23 are provided above and below the mounting margin 22. For this reason, as shown in FIG. 4, the flow path forming member 20 can be easily attached to the partition wall 12 only by aligning the position of the mounting hole 23 with the insert 29 previously embedded in the partition wall 12 and stopping with the bolt 28. it can.
[0026]
The shape of the flow path forming member is not limited to the U-shape, and may be an arch shape as shown in FIG. The flow path forming member 26 shown in FIG. 6B has a shape in which the mounting margin 22 protrudes on both sides from the arch-shaped portion 27, and has a shape similar to or more resilient to a U-shape against water pressure. A thin channel 19 can be provided along the wall.
[0027]
When attaching the flow path forming member 20 to the partition wall 12, it is desirable to sandwich a cushion material 25 such as neoprene rubber. This is because the flow path forming member 20 and the partition wall 12 are brought into close contact with each other so that the oil remaining in the upper part of the oil / water separation section 11 is not mixed into the drainage 3.
[0028]
For example, as shown in FIG. 7, when a tank is formed of concrete, particularly when a relatively large-capacity tank is manufactured by a factory prefabricated concrete block using a durable formwork, each oil-water separation section 11 is required. Can be prefabricated and connected as many as required on site to produce the oil-water separation tank 10 '. Furthermore, in the case of a large oil-water separation tank, it is desirable from the standpoint of strength and economy to provide a slab (upper wall) 42 having a manhole 41 at the top to secure an entrance for maintenance. Accordingly, each concrete block 39 is further constituted by two upper and lower prefabricated blocks 31 and 32. The inner surfaces of the side walls of these blocks 31 and 32 are tapered in order to secure a draft from the mold, and are not vertical. Further, as shown in FIG. 7, when the oil-water separation tank 10 ′ is formed by combining the upper and lower two prefabricated concrete blocks 31 and 32, the upper and lower blocks 31 and 32 have opposite taper 33 and 34 directions. Become.
[0029]
Therefore, in a connection type oil / water separation tank in which a plurality of boxes 39 are connected to assemble one oil / water separation tank, the wall thickness fluctuates in the depth direction. May occur. Therefore, if the flow path forming member 20 is directly attached to the side wall 36 of the box 39 serving as the partition wall 12, a gap is formed between the flow path forming member 20 and the wall surface, and the oil 2 separated from the oil and water may leak. Further, since the flow path forming member 20 of this example adopts a shape that is difficult to deform such as a U-shaped or arch-shaped cross section, it is also difficult to bend the flow path forming member 20 in accordance with a change in the thickness of the wall. . On the other hand, by attaching the flow path forming member 20 to the partition wall 12 with the cushion material 25 interposed therebetween, the flow path forming member 20 can be brought into close contact with the partition wall 12, and leakage of the oil 2 can be prevented.
[0030]
As described above, in the oil / water separation tank 10 of the present embodiment, the flat drainage channel 19 is provided along the partition wall 12 of each oil / water separation section 11, and the drainage water 3 sunk below the separation section 11 is separated from the oil / water. Is supplied to the next separation section 11 from an outflow hole 13 at the upper part of the partition wall 12. This flow path can be considered as a combination of a submerged weir having an opening below and allowing drainage to flow upward from below and a climbing weir having an opening above and allowing overflow drainage to flow. It is possible to prevent the separated oil component 2 from overflowing and flowing out to the next separation section 11, and to prevent the oil component 2 contained in the drained water 1 flowing into the next separation section 11 from being hardly separated. Further, the oil-water separation section 11 also functions as a trap for sand and mud, and can deposit sand and mud on the bottom 16.
[0031]
Further, since the thin drainage channel 19 is formed along the partition wall 12 by the U-shaped thin channel forming member 20, the drainage channel 19 hardly protrudes into the oil-water separation section 11. For this reason, the maintenance work for discharging the mud and sand accumulated by the worker descending to the bottom 16 of the oil-water separation section 11 becomes extremely easy. The oil / water separation tank 10 buried in the underground 9 can be covered with an iron plate 49 on the upper side or by installing a cast iron lid 43 on the manhole 41 so that the upper part can be opened when maintenance in the tank is required. It has become. In the example shown in FIG. 3, the iron plate 49 covering the upper part of the oil / water separation tank 10 is removed, and in the oil / water separation tank 10 ′ shown in FIG. 7, the cast iron lid 43 installed in the manhole 41 is opened. Maintenance can be performed. Unlike the oil / water separation tank using the piping shown in FIG. 8, the drainage path 19 hardly obstructs the opening of the lid 43 and the lowering of the worker in each oil / water separation section 11.
[0032]
Furthermore, the U-shaped or arch-shaped thin flow path forming member 20 has a higher strength against flow than a simple flat plate. Therefore, even if it is a thin drainage channel 19 along the partition wall 12, when the drainage amount increases, the cross section of the flow channel can be reliably ensured, and stable drainage can be performed. Furthermore, since the strength due to the shape is high, the thickness of the stainless steel forming the flow path forming member 20 may be thin, and a low-cost and lightweight flow path forming member can be employed. The flow path forming member 20 may be a rustproof steel plate such as a galvanized material. Also, it is possible to form with plastic such as FRP, but in the case of plastic, there is a material which is deteriorated by fats and oils, so care must be taken in selection. In addition, when a tool such as a scoop is used to discharge mud or sand inside the separation section 11 and hits the flow path forming member 20, the plastic is easily damaged. Therefore, a metal flow path forming member is preferable.
[0033]
Further, a U-shaped or arch-shaped flow path forming member 20 is attached to the partition wall 12, and the partition wall 12 is also used as a wall surface constituting the flow path 19. For this reason, the flow path forming member itself does not need to be a component that forms a flow path by itself, such as a duct or a pipe, and in this regard, the flow path forming member 20 is a light and inexpensive member. It has a tank structure that can separate oil efficiently.
[0034]
Furthermore, by providing a thin drainage channel 19 along the partition wall 12 with a U-shaped or arch-shaped flow channel forming member 20, the inflow point, that is, the drainage pipe 15 or the outflow hole 12 of the preceding separation section 11, The outflow point, that is, the distance to the outflow hole 12 to the next separation section 11 can be increased, and the substantial residence time can be improved. The calculated residence time depends on the capacity of the separation section 11. However, if there is a path in which the inflowing oil-containing wastewater 1 flows out in a short-circuit manner, the wastewater 1 supplied to the next separation section 11 hardly undergoes oil-water separation, and the actual oil-water separation efficiency is low. Therefore, an arrangement in which the pipe is in the middle of the separation section 11 is not desirable. On the other hand, in the oil / water separation tank 10 of the present embodiment, the drainage path 19 is provided along the partition wall 12, so that a long residence time can be obtained. Further, as shown in FIG. 2, in the oil / water separation tank 10 of this example, the position of the drain pipe 15 or the outflow hole 12 flowing into the separation section 11 and the position of the outflow hole 12 discharging to the next separation section 11 are set in the longitudinal direction. The zigzag arrangement allows the drainage to flow in the shortest possible distance to further increase the effective residence time for oil-water separation.
[0035]
The channel forming member 20 having a U-shaped or arch-shaped cross section can be easily attached to and detached from the wall surface of the partition wall 12. If the mounting hole 23 provided in the mounting margin 22 is used, the screw can be easily screwed. Further, the flow path forming member 20 does not need to be connected to the outflow hole 13, and is only required to be attached so as to close the outflow hole 13, so that it is simple. Further, since there is no need to connect to the outflow hole 13, there is no need to bury a connection fitting in the outflow hole 13, and the outflow hole 13 can be constructed with a simple sleeve such as paper. Therefore, the flow path forming member 20 can be easily attached at a factory or a site, and when a worker enters the separation section 11, the flow path forming member 20 can be removed if a larger working space is desired. Also, in the oil-water separation tank of the type in which the drainage channel is formed by the conventional pipe, the flow path forming member 20 of the present example can be easily attached by removing the pipe and embedding the insert in the partition wall. Therefore, it is easy to convert the already installed oil / water separation tank into the oil / water separation tank according to the present invention.
[0036]
In the above description, the present invention is described based on the oil / water separation tank in which the four oil / water separation sections 11 are connected in the longitudinal direction. However, the number of the oil / water separation sections 11 may be three or less, for example, one. There may be more than one. Further, it is also possible to assemble the oil / water separation section 11 in a cross-shaped manner and supply an oil / water separation tank having four separation sections 11 with a substantially square cross section.
[0037]
【The invention's effect】
As described above, in the present invention, a channel forming member having a U-shaped or arch-shaped cross section is attached to a wall surface, and the wall surface is used as a part of the channel, and the flat surface along the wall surface is used. A drainage channel is formed. Therefore, in the oil-water separation section, a flow path that guides the separated wastewater upward without hardly protruding into the section can be formed, and a wide maintenance space for a worker to enter and work is secured. be able to. Further, the U-shaped or arch-shaped flow path forming member according to the present invention is lightweight and easy to attach, and is applicable to an oil-water separation tank in which a drainage path is conventionally formed using piping. By using the road forming member, a maintenance space can be easily secured.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of an oil-water separation tank according to the present invention, in which a part of a side wall is missing to show the inside of a separation section.
FIG. 2 is a longitudinal sectional view showing a planar configuration of an oil-water separation tank.
FIG. 3 is an enlarged sectional view showing a vertical structure of an oil-water separation section.
FIG. 4 is an enlarged view showing a state where a flow path forming member is attached to a wall surface.
FIG. 5 is a view showing a state where a flow path forming member is attached to a wall surface.
FIG. 6 is a view showing a flow path forming member.
FIG. 7 is a view showing a schematic structure of a connection type oil / water separation tank.
FIG. 8 is a diagram showing an example of an oil-water separation tank in which a drainage channel is formed using conventional piping.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Drainage mixed with oil and water 2 Oil 3 Drainage from which oil was separated 5 Mud and sand 10, 10 'Oil-water separation tank 11 Oil-water separation section, 12 Partition wall (side wall)
13 Outflow hole 15 penetrating partition wall 15 Drain pipe, 16 Bottom of oil / water separation section 19 Drainage channel 20 Flow path forming member, 21 U-shaped portion 22 Mounting allowance, 25 Cushion material

Claims (6)

At least one oil / water separation section for retaining the wastewater to separate the oil / water;
An outflow hole provided above a side wall constituting the oil / water separation section,
A substantially U-shaped or arch-shaped member extending from above the outflow hole along the side wall to below the oil-water separation section, and having a horizontal cross section having a long width direction along the side wall; An oil / water separation tank having a flow path forming member that forms a drainage channel extending from below the side wall to the outflow hole. The oil / water separation tank according to claim 1, wherein an insert for attaching the flow path forming member is embedded in the side wall, and the flow path forming member is detachably attached to the side wall. 2. The oil / water separation tank according to claim 1, wherein the flow path forming member is attached to the side wall with a cushion material interposed therebetween. 2. The oil / water separation tank according to claim 1, wherein the flow path forming member is made of stainless steel or rustproof steel plate. The oil / water separation tank according to claim 1, comprising a plurality of the oil / water separation sections, and an outlet of each of the oil / water separation sections is arranged in zigzag. The flow path forming member according to claim 1.

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