JP4718270B2 - Drain treatment device - Google Patents

Description

The present invention relates to a drain treatment apparatus and a filter for separating oil content of drain discharged from a pneumatic system such as a compressor.

Conventionally, this type of drain processing apparatus connects a drain storage tank that is intermittently discharged from a compressor or the like and a processing tank filled with an oil adsorbent with a pipe provided with a pump (for example, , See Patent Document 1).
In such a drain treatment device, the drain that has been stored in the storage tank until the pumping pump is activated rises due to the difference in specific gravity between the oil and water, and the drain that has less oil sinks and is separated.
When the floating oil component overflows and is discharged, and the drainage with a small amount of oil from which the floating oil component has been removed reaches the specified storage amount, the pumping pump is activated, and the drainage in the storage tank is sent into the processing tank by this operation. The oil content of the drain is adsorbed by the material characteristics of the oil adsorbent in the processing tank, and the moisture is filtered.
JP 2004-160412 A

In the above drain treatment apparatus, the oil contained in the drain from which the floating oil has been removed in the storage tank is distributed with a concentration gradient in which the concentration decreases from the upper side to the lower side. Since the drain is introduced into the pressure pump and stirred inside it, it will be emulsified and sent into the processing tank in that state, so oil / water separation with the oil adsorbent in the processing tank The efficiency is very poor, and fresh water that satisfies the standard value cannot be obtained even if it passes through the oil adsorbent.
Moreover, since the oil adsorbent is generally composed of porous fibers made of polypropylene having a high hydrophobicity and lipophilicity, the oil content remains above the oil adsorbent even when the drain is pumped to the processing tank by the pump. Clogged by adsorption, the clogged part becomes resistance to the passage of drain to the oil adsorbent, drain does not pass smoothly relatively early, the oil adsorbent has a small amount of oil adsorption, Due to the short lifetime, there was a problem that the oil adsorbent had to be replaced frequently.

SUMMARY OF THE INVENTION In view of the above problems, the present invention accommodates a drain subjected to primary treatment of oil and water separation, a sub tank provided with a means for communicating with the outside, and a communication pipe provided with an on-off valve at the bottom of the sub tank for opening and closing the pipe A processing tank having an upper portion connected thereto, a filtration chamber provided with a filter for adsorbing oil in order from above and filtering moisture in the processing tank, and a pressure reducing means provided to the filtration chamber. A decompression chamber is provided.
In the drain processing apparatus configured as described above, the pressure inside the processing tank is reduced through the pressure reducing chamber by the pressure reducing means, and then the drain that has flowed into the processing tank from the sub tank is opened through the filter by opening the on-off valve. Suction.
By this suction, the drain is not stirred and emulsified, and smoothly and efficiently passes through the filter. In the process, the drain oil is adsorbed, and the decompression chamber is filtered and purified with high purity water. Get.

Further, the filter is formed by filling a porous and elastic oil / water penetrating material and an oil adsorbing material having oil / water impermeability in a pressure contact state in a filtration chamber, and from upstream by an oil / water penetrating material interposed in the oil adsorbing material. A drain flow path downstream is formed.
As a specific form, a filter element in which an oil water permeation material composed of a belt-like sheet and an oil adsorbent material are overlapped and wound to form a cylindrical body, and the axis of the cylindrical body corresponds to the drain flow path direction. The oil-water penetrating material and the oil adsorbing material consisting of small pieces,
A filter element that is sealed in an oil / water permeable or oil / water permeable wrapping bag and that has a complex drain channel network formed of an oil / water permeable material in the entire wrapping bag is formed in one or more stages. Alternatively, the two types of filter elements are combined and laminated.
This facilitates the smooth and efficient passage of the drain in the filter element so that the oil adsorbent that is in close contact with the oil / water penetrant adsorbs the oil content of the drain while the drain permeates through the oil / water penetrant. By applying a negative pressure to the filter element, the closeness is increased, and the adsorption efficiency of the oil content of the drain in the oil / water penetrating material by the oil adsorbing material is improved.

The sub-tank is equipped with a filter communicating with a drain conduit discharged from the pneumatic system. The filter is provided with a closed surface at the top and bottom, connected to the conduit at the center of the upper closed surface, and from inside the sub-tank. A filter case having an outwardly projecting connection pipe and a plurality of through holes on the entire side surface, a porous and elastic sheet-like oil / water permeation material, and a through hole corresponding to the communication pipe are provided in the filter case. It is characterized by comprising a filter element filled in a pressure contact state so that a plurality of sheet-like oil adsorbents having oil / water impermeability provided are alternately laminated.
As a result, the drain introduced into the center of the filter is discharged to the outside of the filter element through the oil / water penetrant, and in the process of passing, the drain oil is adsorbed by the oil adsorbent that is in close contact with the oil / water penetrant. Stored inside.

Furthermore, the tip of the conduit is arranged in the deep part of the drain storage tank for storing drain discharged from the pneumatic system, the connecting pipe is provided with a vent pipe communicating with the sub tank, and the communicating means is provided with an air circulation port provided above the sub tank. A vent on / off valve is provided for opening and closing, and the decompression means is capable of decompressing the sub tank separately from the decompression chamber.
When the drain of the drain storage tank is introduced into the sub tank, the pressure in the sub tank sealed by the opening / closing valve for venting is reduced by the decompression means, and the drain storage tank of the drain storage tank is similarly reduced through the vent pipe. Aspirate the drain.
By this suction, the drain is not stirred and emulsified, but is introduced into the filter, smoothly and efficiently passes through the filter, and the drain oil is adsorbed in the process, and the oil is contained in the sub tank. To obtain a primary treated drain with low

In short, the invention according to claim 1 is provided in a communication pipe connecting the sub tank and the processing tank in which the inside of the sub tank containing the drain subjected to the primary separation of oil and water is communicated with the outside by the communication means to be at atmospheric pressure. The sub-tank and the processing tank are communicated by opening the open / close valve, and the drain is introduced into the processing tank that has been previously decompressed through the decompression chamber by the decompression means, so that the filter in the filtration chamber sucks the drain. The drain does not flow in as it is agitated and emulsified as before, but passes through the filter in the filtration chamber from the lower layer of the sub-tank with low oil content. Oil and water can be well separated, and high-purity fresh water that satisfies the standard value can be obtained.
In addition, according to the present invention, since the filter processing is performed from the lower layer of the sub-tank with a small amount of oil, the upper part of the filter is not clogged early due to the adsorption of the oil as in the past,
The drain passes smoothly and efficiently, and the drain is spread over the entire filter, and the ability of the filtration process is equalized throughout the entire life, the life is long, and the filter replacement frequency can be reduced.

In addition, the filter built in the sub-tank is provided with a closed surface on the top and bottom, connected to the drain conduit discharged from the pneumatic system at the center of the upper closed surface, and provided with a connecting pipe protruding outward from the sub-tank. A filter case provided with a plurality of through holes, a sheet-like oil / water permeation material having porosity and elasticity in the filter case, and a sheet-like oil having oil / water impermeability provided with a through hole corresponding to the communication pipe Because it consists of filter elements filled in pressure contact so that a plurality of adsorbents are alternately stacked, the drain flow path from the center to the outside is formed in the filter element by the oil / water penetrating material interposed in the oil adsorbent The drain introduced into the center of the filter from the conduit is discharged from the through-hole through the oil-water penetrant to the outside of the filter element. Wood drain can be reliably adsorb oil of oil sorbent closely above and below the oil-water-osmotic material in the process of penetration through which drainage can be obtained drain which is primary treated subtank.

In the invention according to claim 2, the tip of the conduit is disposed in the deep portion of the drain storage tank for storing the drain discharged from the pneumatic system, the connecting pipe is provided with a vent pipe communicating with the sub tank, and the communicating means is provided above the sub tank. A vent on / off valve is provided to open and close the air circulation port provided, and the decompression means is capable of decompressing the inside of the sub tank separately from the decompression chamber, so that when the drain of the drain storage tank is introduced into the sub tank, the vent The sub-tank, which is hermetically sealed by closing the on-off valve, is depressurized by the depressurizing means, and the drain in the drain storage tank is sucked from the conduit whose pressure is depressurized through the vent pipe by this depressurization. Without being emulsified, it can flow into the filter from the lower layer of the drain tank with low oil content, so that it can pass through the filter smoothly and efficiently. The effect of the filter element can be obtained primary treated drain little oil is also in the sub-tank I phase 俟.
Also, after drain filtration in the sub-tank, the sub-tank can be brought to atmospheric pressure by opening the vent on-off valve, so the on-off valve in the communication pipe connecting the sub-tank and the processing tank can be opened. The drain treated as described above can be introduced into the treatment tank from the lower layer with less oil content, thereby reducing the burden due to the filtration treatment in the treatment tank, and further extending the life of the filter in the treatment tank. The frequency of filter replacement can be further reduced.

In the invention according to claim 3, the filter is filled with a porous and elastic oil / water penetrating material and an oil adsorbing material having oil / water impermeability in a pressure contact state in the filter chamber. Since the formation of the drain flow path from the upstream to the downstream can be ensured by the oil / water penetrating material interposed in the filter, the oil / water penetrating material serving as the drain flow path is distributed throughout the filter, and the drain penetrating the oil / water penetrating material is distributed. In addition, the oil adsorbent that is in close contact with the oil / water penetrant can reliably adsorb the oil from the drain that is oozed out of the oil / water penetrant during the process of the drain permeation through the oil / water penetrant. The oil adsorbent can adsorb oil evenly, and the filter can exert its full oil adsorption capacity.
In addition, by applying a negative pressure to the filter by reducing the pressure in the treatment tank, the oil / water penetrant is contracted, and the contact between the drain and the oil adsorbent passing through the oil / water penetrant becomes closer, and the oil / water permeation is performed. The amount of drain that oozes from the material can be increased, and the oil adsorption efficiency of the oil adsorbing material can be further improved.

In the invention according to claim 4, the filter forms a cylindrical body by overlapping and winding an oil / water permeation material composed of a belt-like sheet and an oil adsorbing material, and the axis of the cylindrical body corresponds to the drain flow path direction. Since the filter element is made into one or more stages, the oil adsorbent and the oil / water penetrant are in close contact with each other, and the vertical stripes are alternately arranged in the diameter direction of the filter element. The drain flow path is formed in a straight line in the vertical direction, and the oil adsorbent that is in close contact with both sides of the drain permeates through the flow path can reliably adsorb the drain oil. By forming the drain flow path linearly, the drain passage time can be shortened to shorten the treatment time.

In the invention according to claim 5, the filter is formed by enclosing the oil-water permeable material and the oil adsorbing material, which are small pieces, in an oil-water permeable or oil-water permeable bag, and the entire bag is made of the oil-water permeable material. Since the filter element that stretches around the drain channel network is formed in one or more stages, it is intertwined with the channel network in the process of drain permeation through the drain channel network made of oil-water permeation material. The oil adsorbent can contact the drain flowing through the channel network and adsorb the oil reliably, and the drain channel network is distributed in a complex manner throughout the filter element, increasing the amount of adsorption while processing time is long. The drain purification efficiency can be improved.

In the invention according to claim 6, by combining and laminating the filter elements of claims 4 and 5, the drain processing capacity (oil adsorption amount, filtration time, durability, etc.) by the filter can be adjusted, and the quality of the drain And the practical effect is great.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a simplified configuration diagram showing an example of a drain processing system using a drain processing apparatus.
This drain treatment apparatus is referred to as drain D (hereinafter simply referred to as drain D) that has been primarily subjected to oil-water separation of drain (hereinafter referred to as untreated drain) discharged from a pneumatic system such as a compressor, aftercooler, and air dryer (not shown). ) And a lower part of the sub-tank 2 and a lower part of the sub-tank 2 are connected to the upper part via a communication pipe 4 provided with an on-off valve (electromagnetic valve) 3 for opening and closing the pipe. The processing tank 5 is provided.

The sub-tank 2 is composed of a sealed container having a predetermined volume, and a filter 7 connected to a conduit 6 for guiding untreated drain from a compressor or the like is provided in the center thereof.
In the sub tank 2, an upper limit detection float switch and a lower limit detection float switch (not shown) are provided.
The filter 7 includes a filter case 8 and a filter element 9.
The filter case 8 is formed in a vertically long prismatic shape, provided with closed surfaces 8a and 8b on the top and bottom, a plurality of through holes 10 on the entire side surface 8c, and connected to the conduit 6 at the center of the upper closed surface 8a. At the same time, a connecting pipe 11 protruding from the sub tank 2 is provided.
Further, the connecting pipe 11 is airtightly fixed to the upper surface of the sub tank 2 and has a demister 12 at the upper end, and is connected to the conduit 6 via the demister 12. The appropriate portion of the sub tank 2 has a vent pipe 11a communicating with the inside of the sub tank 2.
Is protruding.

The filter element 9 adsorbs oil and filters moisture, and is an oil / water impermeable material provided with a porous and elastic sheet-like oil / water penetrating material 13 and a through hole 14a corresponding to the diameter of the connecting pipe 11. Each of the sheet-like oil adsorbents 14 having the same shape as the inner cross section of the filter case 8 is formed in a press-contact state so that a plurality of oil-water penetrants 13 and oil adsorbents 14 are alternately stacked. The filter case 8 is filled (in the figure, part of the oil / water penetrating material 13 and the oil adsorbing material 14 are shown).
The oil / water penetrating material 13 is formed by intertwining polyester fibers into a porous and elastic felt shape. Regardless of the raw material, the fiber is felt to maintain a predetermined gap even when an external force is applied. However, it is sufficient if oil water (drain) is allowed to permeate through the gap and the elasticity is restored when the external force is released.
The oil adsorbing material 14 is made of a hydrophobic and highly lipophilic raw material, and is formed to be non-porous so as to have an oil / water impermeability that does not allow permeation of oil / water, and the oil component is mainly adsorbed on the surface thereof. An example of the raw material is polypropylene.
The uppermost layer of the filter element 9 is preferably provided with an oil / water penetrating material 13 as shown in the figure, and the lowermost layer is preferably provided with an oil adsorbing material 14 having no through holes 14a. A wire mesh 15 having the same area is arranged on the top surface of the penetrating material 13, and the untreated drain flowing down from above the connecting pipe 11 is uniformly distributed over the upper surface of the uppermost oil / water penetrating material 13 along the line constituting the metal mesh 15. It is made to spread.

The demister 12 separates the drain containing air introduced from the conduit 6 into air and untreated drain, exhausts the air to the outside, and the drain receiver 16 connected to the upper end of the connecting pipe 11, It comprises a cap 17 with a filter which is crowned on a drain receiver 16 and connected to the conduit 6.
The drain receiver 16 is a cylindrical container having an upper opening, and a communication port with the connection pipe 11 is provided at the center of the bottom, and a predetermined interval is provided in the circumferential direction on the upper opening end surface. A plurality of vents 18 are recessed.
The cap 17 with a filter is composed of a cylindrical box-shaped filter part 19 whose upper part is connected to the conduit 6, and an umbrella part 20 that protrudes from the outer periphery of the filter part 19 at a substantially intermediate position in the vertical direction.
The filter unit 19 is filled with a filter element 21 formed by winding a long strip of stainless steel into a curl shape and winding it up in a substantially dumpling shape, and the bottom of the filter unit 19 passes through a flow-down port 19a of untreated drain captured by the filter element 21. Has been established.
The umbrella portion 20 has a diameter larger than that of the drain receiver 16 and a ring-shaped portion 20a placed on the end surface of the drain receiver 16, and an annular shape longer than the vent hole 18 on the outer periphery of the flange-shaped portion 20a. A hanging part 20b is provided.
Then, the vent 18 of the demister 12 and the vent pipe 11a of the connecting pipe 11 form a series of vent paths between the inside and the outside of the sub tank 2 to form the communication means 1 with the outside of the sub tank 2.

The treatment tank 5 is provided with a filtration chamber 23 provided with a filter 22 for adsorbing oil in order from the top and filtering moisture, and a decompression chamber 25 communicating with the filtration chamber 23 and provided with a decompression means 24. The decompression chamber 25 is provided with a discharge means 26 for the filtered treated water W.
The processing tank 5 is composed of an upper box 27 whose lower side is opened and a lower box 28 whose upper side is opened.
The flanges provided on the outer periphery of the lower end of 27 and the outer periphery of the upper end of the lower box 28 are joined to each other through a gasket 29 and a wire mesh 30 that separates and communicates with the filtration chamber 23 and the decompression chamber 25.
The wire mesh 30 is supported around the lower surface thereof by a rib (not shown) provided on the inner wall of the lower box 28, and stably supports the filter 22 placed on the wire mesh 30.

The upper box 27 has a main body 31 formed in a cylindrical shape, and an upper opening portion of the main body 31 is airtightly closed by a lid 32.
The lid 32 has a small-diameter cylindrical portion 33 penetrating and fixed in the center thereof, and an upper surface portion of the small-diameter cylindrical portion 33 is provided with a projecting tube 33 a having a reduced diameter and connected to the communication tube 4.
The inside of the small diameter cylindrical portion 33 communicates with the inside of the main body 31 and forms a part of the filtration chamber 23.
The inside is formed with the first filtration chamber 23a, and the inside of the main body 31 is formed with the second filtration chamber 23b.

The filter 22 is formed by filling the oil-water permeating material 13 and the oil adsorbing material 14 in a pressure contact state in the filtration chamber 23 (first and second filtration chambers 23a, 23b), and the oil water intervening in the oil adsorbing material 14 The permeating material 13 forms a flow path of the drain D from the upstream to the downstream.
Each of the oil / water penetrating material 13 and the oil adsorbing material 14 is the same as that used for the filter element 9, but the forms thereof are different.

Specifically, the oil / water permeation material 13 and the oil adsorbing material 14 made of a belt-like sheet are overlapped and wound to form a cylindrical body, and the axis of the cylindrical body corresponds to the flow path (vertical) direction of the drain D A filter element 22a (hereinafter also referred to as a roll element 22a) made of one or more stages, or a small piece of oil / water penetrating material 13 and oil adsorbing material 14 is packed with oil / water permeability or oil / water permeability. A filter element 22b (hereinafter referred to as a “packaging element 22”) encapsulated in a bag (not shown) and having a complicated drain D channel network formed of an oil / water permeation material 13 stretched throughout the bag.
Also referred to as b. ) In a single stage or multiple stages, or a combination of filter elements 22a and 22b as shown in the illustrated example.
The small pieces of the oil / water penetrating material 13 and the oil adsorbing material 14 used for the wrapping element 22b are obtained by cutting each of the sheet-like oil / water penetrating material 13 and the oil adsorbing material 14 into about 5 mm ^2. The wrapping bag having the properties is a bag in which the oil / water permeable material 13 is formed in a bag shape, and the wrapping bag having the oil / water permeability is a bag in which a fine mesh is formed in a bag shape.

In FIG. 3, three layers of filter elements 22a and 22b are provided in the first filtration chamber 23a, four layers of filter elements 22a and 22b are provided in the second filtration chamber 23b, and the roll element 22a and the wrapping element 22b are provided. An example of a combination of layers is shown.
According to the laminated example, in the first filtration chamber 23a, the roll element 22a is arranged in each of the upper layer and the lower layer, the wrapping element 22b is arranged in the intermediate layer, and in the second filtration chamber 23b. A roll element 22a is disposed on the uppermost layer, and a wrapping element 22b is disposed on each of the second to fourth layers.
In the illustrated example, the uppermost roll element 22a of the second filtration chamber 23b has a larger diameter than the first filtration chamber 23a and a smaller diameter than the second filtration chamber 23b, and in order to stabilize the shape of the roll element 22a,
A metal ring 34 is fitted on the outer periphery thereof, but it may be the same as the inner diameter of the second filtration chamber 23b. In this case, the metal ring 34 is unnecessary.
FIG. 3 shows only a part of the oil / water penetrating material 13 and the oil adsorbing material 14 only in the upper roll element 22a of the first filtration chamber 23a.

Among the roll elements 22a used in this example, the upper roll element 22a of the first filtration chamber 23a is wound with the oil / water penetrating material 13 on the outer side, and the oil / water penetrating material is wound around the outer periphery of the roll element 22a.
The other roll element 22a is wound with the oil adsorbing material 14 on the outside, and the oil adsorbing material 14 is arranged on the outer periphery of the roll element 22a.
And, in the inner walls of the first and second filtration chambers 23a, 23b, at least the outer periphery of the oil / water penetrant 13 is provided.
The sheet-shaped oil adsorbent 14 having a predetermined thickness is provided around a portion corresponding to the roll element 22a and the wrapping element 22b, and the inner walls of the first and second filtration chambers 23a and 23b, The roll element 22a adsorbs the oil content of the drain D flowing down between the outer peripheral oil / water permeation material 13 and the wrapping element 22b.
Further, in the first and second filtration chambers 23a and 23b, on the upper surface of the uppermost roll element 22a, a wire mesh 15 and a sheet-like oil / water permeation material 13 having the same shape as those of the upper surface are arranged in order from the top. Yes.
As a result, the drain D guided onto the roll element 22a spreads uniformly over the wire constituting the wire mesh 15, and permeates and passes through the oil / water permeation material 13 below the roll element 22a.
The entire upper surface of a is uniformly distributed.
An activated carbon sheet 35 in which activated carbon having an oil adsorption and deodorizing function is added to a sheet-like oil / water adsorption material is placed on the wire mesh 30 which is the bottom of the second filtration chamber 23b.

The combination of the roll element 22a and the sachet element 22b arranged in the first and second filtration chambers 23a and 23b is not limited to the above, and may be appropriately set according to the desired filtration capacity. One filtration element 23a corresponding to the height of one filtration chamber 23a
May be arranged, a multi-stage roll element 22a may be laminated, a single-stage bag element 22b corresponding to the volume of the filtration chamber 23a may be arranged, or a multi-stage bag element 22b may be arranged.
Also, the height and outer diameter of the roll element 22a, the thicknesses of the oil / water permeable material 13 and the oil adsorbing material 14, and which of the oil / water permeable material 13 and the oil adsorbing material 14 are to be wound outside are appropriately set. However, the one arranged in the lower layer compared to the one arranged in the upper layer increases the thickness of the oil adsorbent 14,
That is, it is desirable to wind so that the volume ratio of the oil adsorbing material 14 to the roll element 22a is increased.
Similarly, the mixing ratio of the small pieces of the oil / water penetrating material 13 and the oil adsorbing material 14 in the sachet element 22b is also set as appropriate, but the one arranged in the lower layer is more oily than the one arranged in the upper layer. Adsorbent 14
It is desirable to increase the blending amount of.

The lower box 28 is formed in a funnel shape at the bottom, and the inside of the lower box 28 forms a decompression chamber 25.
The decompression means 24 includes a vacuum pump 37 communicated with the suction chamber 36 above the decompression chamber 25, and a suction tube 36.
And a vacuum on-off valve (solenoid valve) 38 interposed so as to open and close the pipe line.
The discharge means 26 includes a vent on / off valve (solenoid valve) 40 that opens and closes an outside air inlet 39 provided above the decompression chamber 25, and a drain that opens and closes the discharge port 41 of the filtered water W provided below the decompression chamber 25. And an on-off valve (solenoid valve) 42.
An upper open water storage tank 43 for storing the filtered treated water W drained from the discharge port 41 is provided below the processing tank 5.

And the upper limit detection and lower limit detection float switch provided in the sub tank 2, the opening / closing valve 3 provided in the communication pipe 4, the vacuum pump 37 and the vacuum opening / closing valve 38 in the pressure reducing means 24, and the ventilation and drain opening / closing in the discharge means 26 The valves 40 and 42 are connected to a control device (not shown), and the control device is set to operate each device in the following operation procedure.
(1) Operating procedure 1
When the drain D filtered by the filter 7 in the sub tank 2 satisfies the predetermined liquid level, the upper limit detection float switch provided in the sub tank 2 detects the liquid level, and this detection signal is input to the control device. Thus, the vacuum on-off valve 38 is opened and the vacuum pump 37 is operated.
(2) Operating procedure 2
After the above operation of the vacuum pump 37, a predetermined time set by a timer provided in the control device (
When several minutes have elapsed, the on-off valve 3 is opened.
The set time is set in advance so that the inside of the processing tank 5 is in a reduced pressure atmosphere with a predetermined degree of vacuum.
(3) Operating procedure 3
After a predetermined time (several tens of minutes) set by the timer of the control device has elapsed after the opening of the on-off valve 3, the on-off valve 3 is closed and the vacuum pump 37 is stopped. The water on / off valves 40 and 42 are opened.
The set time is set in advance according to the filtration capacity of the filter 22 in the treatment tank 5 and the allowable amount of the filtration water W stored in the decompression chamber 5.
(4) Operation procedure 4
After a predetermined time (tens of minutes) set by the timer of the control device has elapsed after the opening of the vent and drain on / off valves 40 and 42, the vent and drain on / off valves 40 and 42 are closed.
The set time is set in advance so as to drain all of the filtered water W stored in the decompression chamber 5.
(5) Operating procedure 5
Thereafter, the vacuum pump 37 is operated, and the above operation steps 2 to 4 are performed. Such a series of operations reduces the lower limit value (the liquid level indicated by the one-dot chain line in the figure) when the drain D in the sub tank 2 is reduced in water. It repeats intermittently until the limit detection float switch detects.

Next, drain processing by the drain processing apparatus will be described.
The drain containing air introduced from the conduit 6 to the demister 12 is condensed by the filter element 21 and flows into the filter 7 through the drain receiver 16 and the connecting pipe 11 from the downstream port 19a. More exhausted.
The untreated drain that has flowed down into the filter 7 propagates uniformly over the wire mesh 15 at the uppermost part of the filter case 8 and spreads over the oil-water-permeable material 13 at the uppermost layer of the filter element 9. The oil component of the untreated drain is adsorbed by the lower layer oil adsorbent 14 that is infiltrated and passed through the penetrant 13 and is in close contact with the oil / water penetrant 13 in the process.
Further, the untreated drain that penetrates the center of the uppermost oil / water penetrating material 13 passes through the through hole 14a of the oil adsorbing material 14.
In order to cope with the above, the oil water penetrating material 13 below the oil adsorbing material 14 penetrates into the center of the oil water penetrating material 13 and passes through the oil water penetrating material 13, and in the process, the upper and lower parts are in close contact with the oil water penetrating material 13 Oil adsorbent 14
In the same manner, the untreated drain that permeates and passes through the other oil / water penetrants 13 of the filter element 9 is absorbed by the oil adsorbent 14 in close contact with the oil / water penetrant 13. Is adsorbed.
Thus, in the filter element 9, the untreated drain oozes out from the oil / water permeable material 13 by the oil adsorbing material 14 that is in close contact with the oil / water permeable material 13 in the process of osmotic passage from the center of the oil / water permeable material 13 to the outside. The oil content of the drain is adsorbed and removed and flows into the sub tank 2 through the through hole 10 of the drain case 8.
As described above, the drain D to which the oil has been adsorbed has a small oil content but is still contained, and the oil contained in the drain D has a concentration gradient in which the concentration decreases from the upper side to the lower side while being stored in the sub tank 2. It is distributed.

When the drain D stored in the sub-tank 2 satisfies the predetermined liquid level, the upper limit detection float switch detects the liquid level, and the vacuum opening / closing valve 38 is opened by the controller, and the decompression chamber 25 and the vacuum pump
37 is communicated through the suction pipe 36 and the vacuum pump 37 is operated, and the inside of the processing tank 5 is decompressed by the vacuum pump 37 through the decompression chamber 25.
After that, when the on-off valve 3 is opened by the timer of the control device and the sub tank 2 and the processing tank 5 communicate with each other via the communication pipe 4, the inside of the sub tank 2 is communicated to the outside by the ventilation means 1. The drain D inside flows into the processing tank 5 from the communication pipe 4 without any trouble by opening the on-off valve 3.
At this time, the drain D in the sub-tank 2 is stored at the above-mentioned concentration gradient, and the communication pipe 4 is connected to the bottom of the sub-tank 2 so that it flows only from the lower layer with a small amount of oil. Not emulsified.
Since the negative pressure acts on the filter elements 22a and 22b of the first and second filtration chambers 23a and 23b due to the decompression in the processing tank 5, the drain D is sucked into the decompression chamber 25 through the filter elements 22a and 22b. The

The passage state of the drain D of the two types of filter elements 22a and 22b provided in each of the first and second filtration chambers 23a and 23b is generally as follows.
That is, in the roll element 22a, the oil / water penetrating material 13 and the oil adsorbing material 14 which are vertically streaked in the diameter direction thereof.
Are alternately arranged, so that the oil adsorbent 14 that is in close contact with both sides of the flow path from the oil / water permeation material 13 in the process in which the drain D permeates and passes through the vertical streaky oil-water permeation material 13 that is the flow path. It comes into contact with the draining drain D and adsorbs the oil.
In the wrapping element 22b, the oil / water permeable material 13 and the oil adsorbing material 14 made of small pieces that are in pressure contact in the wrapping bag are distributed in a complicated manner, and the complex drain D formed by the oil / water permeable material 13 is formed throughout the wrapping bag. A drainage network in which the oil adsorbent 14 entangled closely with the flow path network oozes out from the flow path network (oil-water permeation material 13) in the process in which the drain D permeates through the flow path network. Contact with D to adsorb the oil.
Further, in the filter elements 22a and 22b in which a negative pressure is applied by the decompression in the processing tank 5, the porous and elastic oil / water penetrating material 13 is contracted. Therefore, the oil / water penetrating material 13 and the oil adsorbing material 14 are compressed.
And the amount of the drainage D that has passed through the oil / water penetrating material 13 is increased, and the oil adsorbing efficiency of the oil adsorbing material 14 can be further improved.
In this way, the roll element 22a and the wrapping element 22 are provided in the first and second filtration chambers 23a and 23b.
b is laminated in multiple layers, and in the process of drain D passing through the respective elements 22a, 22b, the oil content is gradually adsorbed and removed, and the oil content is completely removed in the vacuum chamber 25 and purified. Fresh water (filtered water) W flows down and is stored.

Thereafter, the on / off valve 3 is closed by the timer of the control device, and the sub tank 2 to the processing tank 5 are closed.
The supply of the drain D is stopped, the vacuum pump 37 is stopped, and then the venting and draining on-off valves 40 and 42 are opened.
By opening the on-off valve 40 for ventilation, the decompression chamber 25 and the outside communicate with each other via the outside air inlet 39, and the decompression chamber
25, the pressure inside the pressure reducing chamber 25 is reduced to the atmospheric pressure and the drain opening / closing valve 42 is opened through the discharge port 41.
When the outside communicates with the outside, the filtered water W stored in the decompression chamber 25 can be stored in the storage tank through the discharge port 41 without any problem.
Drain to 43.
Thereafter, the ventilation and drain on / off valves 40 and 42 are closed by the timer of the control device, and a series of filtration processing steps by the processing tank 5 is completed.
This series of filtration processes is intermittently repeated until the lower limit detection float switch detects the lower limit value of the drain D in the sub tank 2.

Next, another example of the drain processing apparatus will be described with reference to FIGS.
FIG. 4 is a simplified configuration diagram showing another example of the drain processing system using the drain processing apparatus. In this drain processing apparatus, the processing tank 5 has the same configuration as the first embodiment, and will be described with reference to FIG. However, in FIGS. 4 and 5, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals,
The description is omitted.
Unlike the above, the sub-tank 2 (filter 7) used in this drain treatment apparatus is not provided with a demister 12, and an on-off valve for ventilation that opens and closes an air circulation port provided above the sub-tank 2 (
(Electromagnetic valve) 40 a is provided, and the on-off valve for ventilation serves as the communication means 1 with the outside of the sub-tank 2, and the connecting pipe 11 of the filter 7 is directly connected to the conduit 6.
The conduit 6 has its tip disposed in a deep portion of an upwardly open drain storage tank 44 that accommodates untreated drain D1 discharged from a compressor or the like, and the conduit 6 has a delivery on-off valve that opens and closes the conduit. (Solenoid valve) 45 is installed.

Above the opening of the drain storage tank 44, an end of a drain pipe 46 that guides an untreated drain D1 generated from a compressor or the like is disposed. The drain pipe 46 is provided with a demister or a drain trap (not shown). The drain storage tank 44 is configured to introduce untreated drain D1 in a state where drain containing air is separated from air.
In the drain storage tank 44, an upper limit detection float switch (not shown) is provided.

The decompression means 24 can decompress the interior of the sub tank 2 separately from the decompression chamber 25.
That is, the vacuum pump 37 in the decompression means 24 is used to decompress the sub-tank 2 and suck the untreated drain D1 in the drain storage tank 44 from the conduit 6.
Therefore, in the suction pipe 36 of the decompression means 24, one end of a branch pipe 36a formed by interposing a separately provided vacuum on-off valve (electromagnetic valve) 38a is connected between the vacuum on-off valve 38 and the vacuum pump 37. The other end of the branch pipe 36a is connected above the sub tank 2 so as to communicate with the inside thereof.

The control device is connected to the upper limit detection and lower limit detection float switch in the sub tank 2, the vacuum pump 37 of the decompression means 24, and the on-off valves 3, 38, 40, 42, and the drain storage tank as described above.
An upper limit detection float switch provided at 44, a vacuum on / off valve 38a, a vent on / off valve 40a, and a delivery on / off valve 45 are connected.
And the control apparatus is set so that each said apparatus may be operated in the following operation procedures.
(1) Operating procedure 1
When the untreated drain D1 stored in the drain storage tank 44 satisfies the predetermined liquid level, the upper limit detection float switch provided in the drain storage tank 44 detects the liquid level, and this detection signal is input to the control device. Thus, the opening / closing valve 38a for the vacuum of the branch pipe 38a and the opening / closing valve for the delivery of the conduit 6
The valve 45 is opened and the vacuum pump 37 is operated.
(2) Operating procedure 2
When the drain D filtered by the filter 7 in the sub tank 2 satisfies a predetermined liquid level, the upper limit detection float switch in the sub tank 2 detects the liquid level, and this detection signal is input to the control device, thereby The on / off valves 38a and 45 for use and the delivery are closed, then the on / off valve 40a for ventilation is opened, and the on-off valve 38 for vacuum of the suction pipe 36 is opened.
(3) Operation procedure 3
When the predetermined time (several minutes) set by the timer of the control device has passed after the opening of the vacuum on-off valve 38 or after the operation of the vacuum pump 37 in the operation procedure 6 described later, as in the first embodiment. Open / close valve 3 is opened.
(4) Operation procedure 4
After the opening of the on-off valve 3, when the predetermined time (several tens of minutes) set by the timer of the control device elapses as in the first embodiment, the valve opening valve 3 is closed and the vacuum pump 37 is turned on. Stop,
Subsequently, the on-off valves 40 and 42 for ventilation and drainage are opened.
(5) Operating procedure 5
After the opening of the venting and draining on / off valves 40 and 42, when a predetermined time (several tens of minutes) set by the timer of the control device elapses as in the first embodiment, the venting and draining on / off valves Close 40 and 42.
(6) Operating procedure 6
Thereafter, the vacuum pump 37 is operated, and the above operation procedures 3 to 5 are performed. Such a series of operations is performed by setting the lower limit float switch of the sub tank 2 to the lower limit value of the sub tank 2 (as indicated by the one-dot chain line in the figure). It repeats intermittently until the liquid level shown) is detected.

Next, drain processing by the drain processing apparatus will be described.
When the untreated drain D1 introduced from the drain pipe 46 satisfies a predetermined liquid level in the drain storage tank 44, the liquid level is detected by the upper limit detection float switch, and the vacuum and delivery on-off valves 38a, 45 are detected by the control device. Is opened, the vacuum pump 37 is operated, and the pressure in the sub tank 2 is reduced by the vacuum pump 37.
At this time, the conduit 6 is depressurized through the vent pipe 11a provided in the connecting pipe 11 connected thereto, so that the untreated drain D1 in the drain storage tank 44 is sucked.
In the drain storage tank 44, the oil contained in the untreated drain D1 is distributed with a concentration gradient in which the concentration decreases from the upper side to the lower side due to the difference in specific gravity between oil and water.
And since the front-end | tip of the conduit | pipe 6 is arrange | positioned in the deep part of the drain storage tank 44, the untreated drain D1 which passes along the conduit | pipe 6 by the said suction | inhalation and is introduce | transduced in the filter 7 is stirred and emulsified. Since the oil only flows from the lower layer of the drain storage tank 44, the passage through the filter element 9 is smoothly and efficiently filtered. The processing is performed in the same manner as described above, and the sub tank 2 is filtered. Drain D is stored.

When the upper limit detection float switch in the sub tank 2 detects the upper limit value of the drain D stored as described above, the control device closes the vacuum and delivery on / off valves 38a and 45, and then vents the on / off valve. 40a is opened and air is introduced into the sub tank 2 through the air circulation port, and the vacuum opening / closing valve 38 of the suction pipe 36 is opened and the inside of the processing tank 5 is depressurized by the vacuum pump 37 through the decompression chamber 25. Is done.
Thereafter, the on-off valve 3 is opened by the timer of the control device, and in the following, the drain D is filtered in the processing tank 5 in the same manner as in the first embodiment. 2 is repeated intermittently until the lower limit of the drain D within 2 is detected.

It is a simplified lineblock diagram showing an example of a drain processing system using a drain processing device. It is an expanded sectional view of a sub tank. It is an expanded sectional view of a processing tank. It is a simple block diagram which shows the other examples of the drain processing system | strain using a drain processing apparatus. It is an expanded sectional view of a sub tank.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Communication means 2 Sub tank 3 On-off valve 4 Communication pipe 5 Processing tank 6 Conduit 7 Filter 8 Filter case
8a Blocking surface
8b Blocking surface
8c Side 9 Filter element
10 Through hole
11 Connecting pipe
11a Vent pipe
13 Oil / water penetrant
14 Oil adsorbent
14a Through hole
22 Filter
22a Filter element
22b Filter element
23 Filtration chamber
24 Pressure reducing means
25 decompression chamber
40a Open / close valve for ventilation
44 Drain storage tank

Claims (6)

A processing tank that contains drain that has been primarily treated by oil-water separation and that is connected to the upper part via a sub-tank provided with means for communication with the outside, and a communication pipe provided with an opening / closing valve that opens and closes the pipe line at the lower part of the sub-tank. And a drain treatment apparatus provided with a filtration chamber provided with a filter for adsorbing oil in order from above and filtering moisture, and a decompression chamber communicating with the filtration chamber and provided with decompression means. The sub-tank includes a filter connected to a drain conduit discharged from the pneumatic system, and the filter is provided with a closed surface on the top and bottom, and is connected to the conduit at the center of the upper closed surface and from inside the sub-tank. A filter case having an outwardly projecting connecting pipe and a plurality of through holes on the entire side surface, a porous and elastic sheet-like oil-water penetrating material, and a continuous filter body are connected to the filter case. Drain processing apparatus characterized by comprising a filter element filled with pressed state so as to alternately stacked and a sheet-like oil sorbent having oil-water-impermeable having a through-hole corresponding to the tube. The tip of the conduit is arranged in the deep part of the drain storage tank for storing drain discharged from the pneumatic system, the connection pipe is provided with a vent pipe communicating with the sub tank, and the communication means opens and closes the air circulation port provided above the sub tank. 2. The drain treatment apparatus according to claim 1, wherein a vent opening / closing valve is provided, and the decompression means is capable of decompressing the sub-tank separately from the decompression chamber. The filter is formed by filling a porous and elastic oil / water penetrating material and an oil adsorbing material having oil / water impermeability in a pressure contact state in a filtration chamber, and from upstream to downstream by the oil / water penetrating material interposed in the oil adsorbing material. The drain processing apparatus according to claim 1, wherein a drain flow path is formed. The filter is formed by stacking an oil water permeation material composed of a belt-like sheet and an oil adsorbing material to form a cylindrical body, and a filter element in which the axis of the cylindrical body corresponds to the drain flow path direction is provided in one or more stages. The drain processing apparatus according to claim 3, wherein: A filter encloses an oil-water-permeable material and an oil-adsorbing material consisting of small pieces in an oil-water-permeable or oil-water-permeable packaging bag, and has a drain channel network formed of the oil-water-permeable material in the entire packaging bag. 4. The drain processing apparatus according to claim 3, wherein the stretched filter elements are formed in one or more stages. The filter is formed by stacking an oil water permeation material composed of a belt-like sheet and an oil adsorbing material and winding them into a cylindrical body, a filter element in which the axis of the cylindrical body corresponds to the drain flow direction, and a small piece. A filter element in which an oil / water permeable material and an oil adsorbing material are sealed in a wrapping bag having oil / water permeability or oil / water permeability, and a drain channel network formed of the oil / water permeable material is stretched around the entire wrapping bag. The drain treatment apparatus according to claim 3, wherein the two are combined and laminated.

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