JPH01139107A - Oil-water separator - Google Patents

Abstract

PURPOSE:To obtain the title oil-water separator having a filter incapable of being deteriorated by water and oil, having the filter surface not damaged by sludge, and capable of removing the contaminant on the filter surface by using a porous ceramic cylindrical filter. CONSTITUTION:The tubular filter 7 made of a porous alumina ceramic is set in a filter vessel 3, and both ends of the filter 7 are liquid-tightly fixed respectively to both end faces of the vessel 3. Emulsified oil-contg. waste water from a vessel 1 is introduced into a chamber 9 from an inlet 4 through a pipeline 2, a pump 5, and a primary oil-water separation filter 6. The filtrate from the filter 7 is discharged from the chamber 8 through an outlet 12. Meanwhile, a part of the oil contg. waste water introduced into the chamber 9 from the inlet 4 is discharged as the liq. concentrate from the vessel 3 through an outlet 10, and then returned to the vessel 1 through a pipeline 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an oil-water separation device for oil-containing wastewater using a ceramic filter.

[Prior Art] Oil-containing wastewater to be subjected to oil-water separation includes, for example, floating oil in which aggregated oil droplets are gathered on the liquid surface, and dispersed oil in which relatively thick oil droplets are mixed in water and dispersed. They contain oils or emulsified oils, mainly emulsified by surfactants and active aids, and are discharged in all areas of industry. For example, polishing water from the technical fields of petroleum refining, steel rolling, area 1J processing, food manufacturing, and machining is a typical oil-containing wastewater.

These oil-containing wastewaters are treated by so-called methods such as the reverse osmosis method, the limit W'-appropriate method, and the precision e-proper method.

[Problems that remain unsolved by the invention] Although the method has many advantages, such as being particularly effective for emulsifying waste liquids, it is difficult to prevent membrane surface contamination11 or remove contamination that has occurred on the membrane surface. There is still room for development in this respect. In addition, if the membrane material is a polymer compound, it is not suitable for oil-water separation of water and oil emulsions because it is less than 1g, ignoring solvent resistance to water and oil, and sludge may get mixed into the membrane. Rub each film surface one by one.

The present invention is based on the above-mentioned points, and its purpose is to provide a filter whose material does not change even when immersed in water or oil, and whose filter surface is not damaged by sludge. The object of the present invention is to provide an oil/water separator capable of removing contamination generated on a filter surface.

Means for Solving Problem E] According to the present invention, the object is to provide a container, and to partition the interior of the container into a first chamber and a second chamber, so that both ends are substantially liquid-tight to the inner surface of the container. It is stuck to the oil-containing wastewater! a cylindrical filter made of porous ceramics for filtering water; an inlet provided in the container at one end of the filter for introducing the oil-containing wastewater into the first chamber; a first outlet provided in the container at the other end of the filter to discharge the oil-containing wastewater rIFf from the chamber; and a second outlet provided in the container for discharging oil/water l1.
This is achieved by lIl loading.

[Function 1] According to the device of the present invention, since the filter is made of ceramics, the filter has water resistance and bending resistance, and the filter has high breaking strength, so that the filter surface is not damaged by sludge. can be prevented. In addition, the device of the present invention allows oil-containing wastewater to flow from an inlet provided in the container on the - end side of the filter to a first loss outlet immersed in the container on the (t!! end side of the filter). Therefore, a flow of oil-containing wastewater is formed along the filter surface that defines the first chamber, and as a result, the oil-containing wastewater introduced into the first chamber flows along the filter surface that defines the first chamber. - The contamination accumulated on the filter surface is flushed away towards the first 11 outlet.
11. Cleaning of the filter can be carried out at the same time as the 81 filtration of oil-containing wastewater.

The first chamber of the device of the invention may be provided inside the filter or outside the filter.

In the filter according to the present invention, when the first chamber is provided inside the filter, the pore diameter of the pores in the innermost layer is 0.05 μs.
It is preferably a cylindrical multi-layer structure, such as a cylindrical three-layer structure, in which the pore diameter increases from the inside to the outside, and is made of porous ceramics made of alumina. Here, the thickness of the innermost layer is 10 to 40-'
r- is preferable, and the pore diameter of the pores in the innermost layer of the filter is 0.2/Ill, more preferably 0.01 to 0.1
2IJ! R1 is preferably 0.11IIR.

Thereby, oil and water can be separated efficiently. In this way, the outer portion of the filter, which has a multilayer structure in which the pore diameter gradually increases from the inside to the outside, serves to support the innermost layer.

The oil-containing wastewater introduced into the apparatus of the present invention is 0.2 to SKg
It is preferable to pressurize to /chi, so that the flow rate of the oil-containing wastewater along the filter surface can be suitably maintained, and the amount of filtration of the oil-containing wastewater can be maintained appropriately.

Furthermore, a pretreatment oil/water separation filter having a relatively large pore diameter of 1 fl'1 or more may be provided on the inlet side of the apparatus of the present invention. removes large emulsions, oils and sludge, and as a result, one of the filters of the device of the invention
1, clogging and contamination can be reduced, and the apparatus of the present invention preferably removes emulsions having relatively small diameters.

As the ready-to-use oil/water separation filter, a ceramic cylindrical multilayer filter is preferable, and the pore diameter of the innermost layer is 1.
Particularly preferred is 0 to 1100 JI.

Furthermore, when treating materials with a high solid content, a filter made of ceramic foam with a three-dimensional network structure having continuous pores with a pore size of 0.1 to 5 mm, or a filter with a mesh size of 0. The filtration efficiency can be increased by providing a net of .5 to 5rnIn.

In general, the device of the present invention may be subjected to backwashing of the filter with a cleaning liquid. At this time, it is preferable to use caustic soda as the cleaning liquid.

The filter of the device of the present invention may be a polygonal prism, preferably a hexagonal prism, with a plurality of through holes, preferably circular cross sections, provided along the longitudinal direction of the prism.

Among ceramics, alumina with a purity of 99% or higher is preferably used as the material for the filter of the device of the present invention.

Specific Example 1 The present invention will be explained in more detail below using preferred specific examples shown in the drawings.

In the figure, a liquid container 1 is filled with emulsified oil-containing wastewater. This container 1 is connected to an inlet 4 provided at one end of a cylindrical filter container 3 with both ends closed, by an appropriate piping 2. A pump 5 is provided for supplying oil-containing wastewater to the inlet 4. Between the pump 5 and the inlet 4, there is a primary oilwood separation filter made of a spongy substance for removing relatively large-diameter emulsions, oil, and sludge contained in the oil-containing wastewater supplied by the pump 5. 6 is r:Q +J and C.

Inside the container 3, the pore diameter is 0.2JJ! A tubular filter 7 made of alumina (II) is housed in the container J3, and both ends of the filter 7 are fixed to both end surfaces of the container 3 in a fluid-tight manner.

The filter 7 divides the inside of the container 3 into a chamber 8 outside the filter 7 and an 'i! chamber 8 inside the filter 7. Room 9 is divided into J3 and Room 9.
communicates with the inlet 4 at one end surface of the container 3. lj[outlet 10 is installed on the other end surface of the container 3,
The chamber 9 also communicates with an outlet 10.

The outlet 10 is connected to a suitable pipe 11 and to the container 1. At the bottom of the container 3, there is a slot 1 that communicates with the chamber 8 and an outlet 1.
2 is provided.

The operation of the device of the present invention will be explained below.

The oil-containing wastewater in the container 1 is supplied to the filter 6 by the pump 5, and the filter 6 removes the emulsion having a relatively large diameter, oil, and sludge in the oil-containing wastewater. The oil-containing wastewater that has passed through the filter 6 is introduced into the chamber 9 via the filter 14.
The emulsion, which has a relatively small diameter, is then filtered by the filter 7. This filtrate is discharged from chamber 8 via outlet 12 . On the other hand, a part of the oil-containing wastewater introduced into the chamber 9 from the inlet 4 becomes a concentrated liquid and is introduced into the outlet 10.
is discharged from the container 3 via the pipe 11, and the volume VS
It is returned to 1.

In the chamber 9 , the oil-containing wastewater flows along the inner circumferential surface of the filter 7 in the longitudinal direction of the filter 7 , so that the flow of the oil-containing wastewater carries the contamination, or emulsion, accumulated on the inner circumferential surface of the filter 7 to the discharge port 10 . The filter 7 can be washed away and the filter 7 can be washed away.

Fig. 2 shows the results of using the oil-containing wastewater as wastewater from the electrical component manufacturing process by electrical discharge machining and passing it through the apparatus of this specific example. Note that the liquid in this specific example is made of organic carbon (
TOC) is emulsicone water of 2940 ppm,
Also, the water hammer passing through the filter 7 is 100ρ/m'-h
It is. Emulsion 1 is mixed with oil-containing waste liquid ([Immediately after injection, the particle size is small, and when 1 is placed, this small emulsion 1
The volume increases to some extent.

If J is shown in FIG. Line 51) in Figure 2 is 7201) Ilm, 0.11JIn) is filtered with Ilta. Line 52) in Figure 2 is 590 ppm.
When oil-containing wastewater is generated and filtered with a 0.21m filter every second time, the line 53) in Figure 2 is 600ppm.
Hereinafter, it will be referred to as F19. 1 A three-stage filtration type filtration device using a specific example of the present invention will be explained with reference to FIG. The liquid container 11 is filled with emulsified oil-containing wastewater.

This container 11 is connected to one end of a cylindrical filter container 12 with both ends closed by a suitable piping 13. A pump 14 is provided for supplying. A cylindrical filter 15 made of ceramic foam and having a three-dimensional network structure with a pore diameter of 0.5 mm is housed inside the container 12 , and one end of the filter 15 is connected to the pipe 13 . The other end of the filter 15 is connected to the container 11 by a suitable pipe 16. Filter 1
The first filtrate that has been filtered through the filter 5 is led to a liquid container 18 via a discharge port 17.

The liquid container 18 is connected to one end of a cylindrical filter container 19 whose both ends are closed by a suitable pipe 20, and a part of the pipe 20 is connected to the first filtrate in the container 18. A pump 21 is provided for supplying the water. Inside the container 19, the pores have a diameter of 10-100-
A tubular filter 22 made of alumina is housed in the container 19 and the filter 22 (the structure and function (14) are similar to those shown in FIG. 1. 1 A part of the filtrate becomes a concentrated liquid and
It is returned to the 'CR: sweeper 18 by the r pipe 23. The second filtrate filtered by the filter 22 is led to the liquid container 25 via the IJI outlet 24.

The liquid container 25 is connected to one end of a cylindrical filter container 26 with both ends open, by a suitable pipe 27, and in the middle of the pipe 27, the 28j filtrate in the container 25 is transferred for 1 yen. A pump 28 for supplying the vessel 26 is submerged. Inside the volume 75326, there are pores (¥0.1
~1,81jIII tubular filter 2 made of aluminum
呵) is accommodated. These containers 26 and filter 2
9 is similar in structure and function to the device shown in FIG.

A portion of the second filtrate introduced into the filter 29 becomes a concentrated liquid and is returned to the container 25 through an appropriate piping 30.

The third filtrate filtered by the filter 29 is discharged [1
It is discharged from the container 26 via 31.

The effects of the apparatus shown in FIG. 3 will be explained using FIGS. 4 and 5. In the graph of FIG. 4, the horizontal axis shows the particle size of the filtered solids, and the vertical axis shows the cumulative percentage of solids. The solid line 41 is the data in the filter 29, broken F
A42 is the data in the filter 22, and the dashed line 43 is the data in the filter 15. According to FIG. 4, it can be seen that the filter 15 can remove solids with a particle size of 0.5M or more, and the filter 22 can remove solids with a particle size of 10-1. According to another measurement, no solid content was detected in the third filtrate discharged from the first outlet 31.

In the graph of FIG. 5, the horizontal axis shows the filtration time, and the vertical axis shows the underestimation of e. The actual FA 44 is the data on the filtration amount of the apparatus shown in FIG. 1, and the broken line 45 is the data on the filtration amount of the filter 29 in the apparatus shown in FIG. According to Figure 5, the third
A three-stage filtration type filtration device such as the 5A position shown in the figure has one stage 11
Since a large solid content is removed from the oil-containing wastewater in advance by the filter and the two-stage filter, the F' 3G IlN of the three-stage 1] filter is t[
It is much larger than a filtration device that does not perform pre-treatment.

Furthermore, in the apparatus shown in FIG. 1, the filter 7 has a pore diameter of 0.02 cape, and the 2-tile filter has a pore diameter of 0.02 cape.
For both cases with 1jIIn 0 and 1p filters, the results of first filtering the stock solution, which is obtained by mixing water with grinding oil, iron as sludge, activated carbon, and lubricant and stirring, are as oil-containing wastewater. It is shown in Figure 6. In FIG. 6, a solid line 54 indicates the amount of filtration by the 0.11 JM filter, and a broken line 55 indicates the amount of filtration by the 062-filter. In addition,
The measurement conditions for the 0.11 JIR filter are that the temperature of the stock solution is 30 to 41°C, and the liquid pressure at the inlet 4 is 2.1!
JlC&G, the hydraulic pressure in discharge port 12 is 0.4! ＋〜
0.5 K9/JG, circulation Fu fit of stock solution is 5
100-5200! l/1), and the measurement conditions for the 0.2-filter are that the temperature of the stock solution is 32 to 45°C, and the liquid pressure at the inlet 4 is 2.1 to 2.3 Kg/cat.
G, the fluid pressure at the discharge port 12 is 0.4 to 0.5 K.
The circulation amount of g/c i G1 stock solution is 4500~5000j!
/ h.

According to Fig. 6, compared to the case of 0.21m filter,
．． The amount of filtration is larger in the case of the IJJIR filter, and it can be seen that the filter is not clogged. This is because in the case of a 0.1-filter, the sludge does not clog the pores of the filter 7 and is more likely to be washed away by the stock solution flowing along the inner peripheral surface of the filter 7.

By the way, 0. IIJ! The R filter has a lower TOC value of the filtrate from the outlet 12.

[Effects of the present invention] According to the device of the present invention, since the filter is made of ceramics, the filter has excellent water resistance and oil resistance. It is possible to pass an irI in a high range (not exceeding the ignition point of 4). In addition, the apparatus of the present invention is configured such that oil-containing wastewater flows from an inlet provided in a container at one end of the filter to a first initial outlet provided in the container at the other end of the filter. 19, forming a flow of oil-containing wastewater along the filter surface defining the first chamber.
As a result, the oil-containing water introduced into the first chamber can flush away the contamination deposited on the filter surface defining the first chamber toward the first outlet, and the oil-containing water can flow away toward the first outlet. At the same time as the 81st pass, I also cleaned the filter.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing one specific example of the device of the present invention, FIG. 2 is a graph showing the effects of one specific example of the device of the present invention, and FIG. 3 is a first example of the device of the present invention. Fig. 4 is an explanatory diagram of the effect of the device shown in Fig. 3;
FIG. 5 is a graph 11 for comparing the filtration state between one specific example of the device of the present invention and the device shown in FIG. 3. FIG. 6 is a graph for comparing the effects of a 0.1 m filter and a 0.21 JIR filter. It is a graph. 3...Filter container, 4...Inlet port,
7... Filter, 10.12... Exhaust port. Agent 4T Physician Month A Issue 1 Drawing number Fig. 2 Fig. 3 Fig. 4 Fig. 5 Request 171 (h)

Claims (6)

[Claims] (1) A container, and a porous ceramic material for filtering oil-containing wastewater, each of which has both ends liquid-tightly fixed to the inner surface of the container to partition the interior of the container into a first chamber and a second chamber. an inlet provided in the container at one end of the filter for introducing the oil-containing wastewater into the first chamber, and an inlet for discharging the oil-containing wastewater from the first chamber. A first outlet provided in the container on the other end side of the filter, and a second outlet provided in the container for discharging the filtrate of the oil-containing wastewater filtered by the filter from the second chamber. An oil/water separator comprising: a discharge port; (2) The apparatus of claim 1, wherein the first chamber is inside the filter. (3) The filter has a pore diameter of 0.05 in the innermost layer.
Claim 2: The cylindrical multilayer structure is made of porous ceramics made of alumina and has pore diameters of 1.8 μm to 1.8 μm, and the diameter of the pores increases from the inside to the outside. The device described in. (4) The pore diameter of the pores in the innermost layer of the filter is 0.07~
Claim 3 characterized in that the diameter is 1.2 μm.
Equipment described in Section. (5) The pore diameter of the pores in the innermost layer of the filter is 0.1 μm
The device according to claim 4, characterized in that: 6. The device of claim 1, wherein the first chamber is outside the filter.