JPH0645604U - Two-liquid separation device for mixed oil-water - Google Patents

Abstract

(57) [Summary] [Purpose] When a small amount of water is mixed with a large amount of oil, or when oil is emulsified by a surfactant, etc.
An object of the present invention is to provide a two-liquid separation device capable of continuously and efficiently obtaining a purified liquid from a mixed liquid in which liquid particles of each of the two liquids are extremely strongly bonded. [Structure] A plurality of charge plates to which a voltage is applied are arranged to face each other, and a stock solution of a two-liquid mixed liquid continuously supplied from the outside of the apparatus is flowed in a downward flow between the charge plates in a downward flow to perform a primary treatment. And a downward-flow separation tank that communicates with the downward-flow separation tank at the bottom and performs a secondary treatment while floating the primary treatment liquid introduced through the communication passage from the lower side to the upper side. Then, the two-liquid separation of an oil-water mixed liquid, etc., in which an outlet for the separated low specific gravity liquid is provided on the upper side of the upflow separation tank and an outlet for the separated high specific gravity liquid is provided on the bottom side It is a device.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a device for separating a refined liquid from a mixed liquid of two liquids having a difference in specific gravity, such as an oil-water mixed liquid, and particularly a small amount of water is continuously mixed with a relatively large amount of oil. In such cases as when the oil floating in water is emulsified by the mixture of surfactants, the two liquids are used for mixed liquids in which the degree of suspension of the two liquids is severe and the degree of bonding of the two liquid particles is strong. Separation device

[0002]

[Prior art]

 There are various devices for separating each purified liquid from a two-liquid mixed liquid such as an oil-water mixed liquid, and the present inventor has proposed it as Japanese Patent Application No. Hei 2-162361 as a particularly effective device. There is something. As shown in FIG. 6, an upper open type separation tank d is provided, which divides the tank interior space into an oil / water separation space b and a separated water storage space c by a partition plate a. Is formed in the oil-water separation space b while a discharge passage f is formed in the upper part of the side wall which forms the oil-water separation space b. Is arranged so as to face each other. Then, in this device, the undiluted solution is supplied from below to the oil / water separation space b in which the electric field acts, and in the oil / water separation space b, the oil droplet particles separated from the water droplet particles are made coarse while floating. The floating oil layer h formed in the upper layer portion of the oil / water separation space is directly recovered from the oil discharge port f formed in the side wall of the oil / water separation space. The separated water is allowed to flow into the adjacent separated water storage space c, the separated water filled in the separated water storage space c is introduced into the adjacent tank i, and then the water is discharged from the lower portion of the tank. .

[0003]

[Problems to be solved by the device]

 According to the above apparatus, the purified liquid can be efficiently separated from the two-liquid mixed liquid, but the type of the two-liquid mixed liquid to be treated is limited. That is, the above-mentioned apparatus can efficiently obtain a purified liquid when the ratio of the low specific gravity liquid is smaller than that of the high specific gravity liquid, such as when a large amount of water is mixed with a small amount of oil. When the ratio of the low specific gravity liquid is higher than that of the high specific gravity liquid, such as when a small amount of water is mixed with oil, the low specific gravity liquid particles and the high specific gravity liquid particles are strongly bonded. The separation effect was somewhat insufficient.

Further, even when the ratio of the high-density liquid is high in the mixing ratio of the two liquids, for example, when the oil floating in water is emulsified by the mixture of the surfactant, the suspension of the two liquids Even in the case of a mixed solution having a severe degree and a strong degree of bonding of two liquid particles, the separation effect was slightly insufficient. The present invention has been made in view of the present situation, and it is a liquid of each of the two liquids, such as when a small amount of water is mixed with a large amount of oil or the oil is emulsified by a surfactant. The purpose of the present invention is to provide a two-liquid separating device for a mixed liquid having extremely strong particle binding.

[0005]

[Means for Solving the Problems]

 In order to solve such problems, the present inventor has earnestly studied the direction of flowing the mixed solution in the tank, the arrangement position of the inflow port of the undiluted solution, and the discharge port of the purified solution after separation, and as a result, the present invention was achieved. It was done. The present invention, which has solved such a problem, has a plurality of charge plates to which a voltage is applied facing each other, and a stock solution of a two-liquid mixture continuously supplied from the outside of the apparatus is directed downward from above between the charge plates. Downward flow separation tank that performs primary treatment by flowing in a downward flow, and secondary treatment that floats the primary treatment liquid that is in communication with the downward flow separation tank at the bottom and is introduced through the communication passage from above to above. And a discharge port for the separated low specific gravity liquid on the upper side and a discharge port for the separated high specific gravity liquid on the bottom side. It has a feature.

The arrangement of the charging plates facing each other in the upflow separation tank is appropriately selected depending on the type of the liquid to be treated, but it is considered that the charging plates are arranged vertically, for example.

Further, in order to enhance the effect of separating two liquids due to charging, it is preferable to interpose a porous dielectric having a multi-electrode effect between the charging plates. The charging voltage is appropriately selected according to the type and concentration of the liquid to be treated, and either direct current, alternating current or superimposed voltage of both can be adopted. For example, in the case of alternating current voltage, it is within the range of 0.5V to 3000V / cm. Is selected as appropriate.

Further, as a means for collecting a two-liquid mixed solution in which a small amount of low specific gravity liquid is dispersed in a large amount of high specific gravity liquid floating in the upper layer of the stock solution tank, for example, a float is provided on three columns arranged at 120 ° angle. It is preferable to use the float suction configured to be attached.

[0009]

[Action]

 The operation mode of the two-liquid separation device having such a configuration is as follows. Here, an oil-water mixed liquid will be described as an object, but the subject of the present application is also applied to other liquids having different specific gravities, and its operation mode is an operation mode for separating an oil-water mixed liquid. Is almost the same as. First, the stock solution of the oil-water mixture to be treated is poured into the downward flow separation tank from the upper side of the downward flow separation tank. This stock solution is a two-liquid mixture in which a small amount of water is dispersed in a large amount of oil liquid, and the degree of suspension is severe, and the liquid particles of each of the two liquids are extremely fine and strongly bonded.

Since the upflow separation tank communicates with the adjacent downflow separation tank in the lower part, and the upflow separation tank is provided with a discharge port, the upflow separation tank is located above the upflow separation tank. A downward flow is generated. Then, the oil-water mixture passes downward between the charged plates to which a voltage is applied, and during this time, an electric field acts on the oil-water mixture in addition to the physical separation action due to the difference in specific gravity. As a result, the zeta potential possessed by each of the water droplets is neutralized, and the repulsive force due to the electric double layer acting on the water droplet surface is weakened.As a result, the aggregation and coarsening phenomenon of water droplet particles due to the intermolecular attractive force gradually progresses. The settling of water droplets is gradually carried out, and the separation of oil water progresses. Then, in this process, the oil liquid, which has begun to accumulate at a position relatively higher than the water liquid, pushes a small amount of water liquid further downward due to its weight and downward flow. The water liquid pushed downward moves to the adjacent upflow separation tank together with the oil liquid while being pushed by the oil liquid, and then the secondary treatment is performed in the tank along the upward flow from the bottom to the top. As a result, the floating oil layer is formed in the upper layer of the tank and the water layer of relatively high purity is formed in the lower layer. The separated water is pushed by the oil liquid and discharged to the outside of the equipment through a drainage port provided on the bottom side of the upflow separation tank that allows adjustment of the drainage level, while the separated oil liquid drains the water liquid. While pushing out from the mouth, it reaches upward along the upward flow and is continuously collected from the oil discharge port provided on the upper side of the upward flow separation tank. In the case of a mixed liquid with a high degree of suspension, which is the subject of the present invention, the degree of oil-water separation is still insufficient only by the treatment in the downflow separation tank. After the primary treatment, the upflow separation tank also separates oil and water as the secondary treatment, and in the downflow separation tank that functions as the primary treatment tank, there is a liquid flow and high specific gravity liquid. Since the descending and settling directions of the water liquid are the same, an excellent separation effect can be realized and highly refined oil liquid can be recovered.

In addition, a voltage is applied between the charge plates in the same manner as in the downflow separation tank, by interposing a porous dielectric having a multi-electrode effect or in the upflow separation tank as the secondary treatment tank. When a plurality of charged plates are installed vertically, the refined oil with a lower water content can be efficiently collected.

[0012]

【Example】

 Next, the details of the present invention will be described based on the illustrated embodiment. FIG. 1 (a) is a longitudinal sectional explanatory view showing a first embodiment of the present invention, and FIG. 1 (b) is a lateral sectional explanatory view of the same embodiment. In the figure, A is a box-shaped tank body having an open top, and a partition plate 2 having a gap serving as a communication path 1 is hung at the center of the tank body A, and the space inside the tank body A is suspended. Is divided into a downward flow separation tank A1 and an upward flow separation tank A2.

A stock solution inlet 3 for supplying a stock solution of an oil-water mixture is provided at an upper position of the downflow separation tank A1. The undiluted solution is introduced by gravity flow, and it is also possible to use a pump. However, when using a pump, it is necessary to use one with a small stirring effect in order to avoid stirring oil and water. In the figure, reference numerals 4a and 4b denote charging plates horizontally opposed to each other in the downflow separation tank A1. One charging plate 4a is a ground electrode and has the same potential as the tank A, and the other is the other. The charging plate 4b serves as a load electrode and supplies an AC voltage of 0.5 to 3000 V / cm from the charging power source 5 between the charging plate 4a and the charging plate 4a serving as the earth electrode. The AC voltage was selected as the applied voltage in order to avoid electrolytic corrosion, but it can also be DC voltage if the oil-water mixture has high conductivity. The magnitude of the voltage is appropriately selected depending on the state of the oil-water mixture, and generally, the smaller the oil droplet particles, the higher the applied voltage needs to be. For example, when the oil-water mixture is emulsified, 500 to 3000 V is applied. It is preferable to apply a high voltage of / cm 2. Further, an insulating plate 7 is arranged between the charging plate 4b and the outer plate 6 constituting the tank body to electrically insulate the both.

The upward flow separation tank A2 separates the oil-water mixed liquid that has been subjected to the primary treatment introduced from the downward flow separation tank A1 by the difference in specific gravity as the secondary treatment, and also provides the purified liquid after the separation. It is a space for collection. An upper part of the upflow separation tank A2 is provided with an oil drain gutter 8 for collecting floating oil, and a drain pipe 9 extending upward from the lower part of the tank is continuously provided. The oil drain gutter 8 is for naturally discharging the floating oil accumulated in the upper layer of the upward flow separation tank A2, is provided so as to be movable in the height direction, and adjusts the height appropriately to adjust the recovery level of the floating oil. It is configured to be able to. A flexible pipe is used as the drainage pipe 9, and the drainage level can be adjusted by changing the height position of the pipe tip port 10.

A partition plate 11 for water storage is provided in a standing state near the boundary between the downward flow separation tank A1 and the upward flow separation tank A2 on the bottom surface of the tank body. This water storage partition plate 11 is filled with water to the upper edge of the water storage partition plate 11 on the side of the downflow separation tank A1 at the time of starting the present device, so that the inside of the downflow separation tank A1 immediately after the start. This is to prevent the stock solution from being directly discharged from the drainage pipe 9 even when the stock solution is poured into the tank, and its height is set appropriately. Further, level adjusters 12 for height adjustment are attached to the four corners on the lower surface of the tank A, and the tank A can be kept horizontal by individually adjusting each level adjuster 12.

2A and 2B show a second embodiment of the present invention. In this embodiment, the charging plates 4a 'and 4b' provided in the downflow separation tank A1 are arranged in the vertical direction.

3 (a) and 3 (b) show a third embodiment of the present invention, in which the charging plates 4a and 4b are provided side by side in the downflow separation tank A1 and also in the upflow separation tank A2. This is the case where the charge plates 13a and 13b are arranged and a potential is applied to the 13a and 13b by the loading power source 5. FIGS. 4 (a) and 4 (b) show a fourth embodiment of the present invention, in which the charging plates disposed in the downward flow separation tank A1 and the upward flow separation tank A2 are both vertically installed. Is.

In the above-mentioned embodiments, the charging plates are simply oppositely arranged, but a dielectric material such as a porous material or a net-like body having a multi-electric effect is interposed between the charging plates, and a myriad of electrodes are provided. It is also possible to achieve the same effect as forming the electrode.

A method of collecting floating oil as a stock solution from a stock solution tank (not shown) can be appropriately adopted, but it is also possible to use a float suction as shown in FIGS. 5 (a) and 5 (b), for example. . The float suction 14 has three support rods 15, 15, 15 which are arranged at an angle of 120 ° to each other, and the floats 16, 16, 16 are attached to the support rods 15, 15, 15 at the intersections of the three support rods 15, 15, 15. The suction port 18 whose other end is connected to the suction hose 17 is positioned at the position. The float suction 14 can adjust the set height of the suction port 18 on the basis of the oil / water interface, and can float following the vertical movement of the oil / water interface X2 located below the oil surface X1.

The operation mode of the present apparatus having such a configuration is as follows. Here, the description will be given centering on the embodiment shown in FIG. 1, but the operation modes of the other embodiment devices are substantially the same. Further, although the description will be made here for the oil-water mixed liquid, the subject of the present application is also applied to other liquids as long as it is a mixed liquid of two liquids having different specific gravities, for example, for water mixed with a small amount of Freon. It can also be applied to. At the time of starting, the bottom space on the side of the downward flow separation tank A1 partitioned by the water storage partition plate 11 at the bottom of the tank A is filled with water. This water plays a role of preventing the undiluted solution from being discharged from the drainage pipe 9 when the undiluted solution is introduced into the downflow separation tank A1 at the same time when the present apparatus is started, even if a large amount of the undiluted solution is introduced. Simultaneously with or before the start-up of the present apparatus, the stock solution of the oil-water mixture to be treated is poured into the downward flow separation tank A1 from the upper side of the downward flow separation tank A1. The stock solution may be introduced gradually or in large quantities at one time. The stock solution will eventually be filled to the level indicated by P in the figure. However, if the stock solution is poured to this level from the beginning, the stock solution may flow out from the drain pipe 9, so the oil / water separation is not progressing in the initial stage. Then, the liquid surface is positioned slightly below the level P.

The oil-water mixed liquid that has flowed into the downward flow separation tank A1 flows downward from above in the tank and passes in the downward flow while bypassing between the charging plates 4a and 4b. The oil-water mixture is subjected to an electric field in addition to the physical separation due to the difference in specific gravity. This electric field action neutralizes the zeta potential of each water droplet particle by the electric field, weakening the repulsive force due to the electric double layer acting on the water droplet surface. Gradually progresses. Since the undiluted solution to be treated by the present invention has an extremely strong bond between oil droplet particles and water droplet particles, complete separation of oil water cannot be achieved by treatment only in the downward flow separation tank A1, and the downward flow separation tank A1 It can be said that the internal processing contents are primary processing contents.

In the downward flow separation tank A1, a downward flow oil liquid pushes down a small amount of water liquid by its weight, and the downward pushed water liquid is further pushed by the oil liquid to separate adjacent upward flow liquids. Move to the tank. Next, for the two-liquid mixed liquid that has flowed into the upward flow separation tank A2, oil-water separation due to the difference in specific gravity as the secondary treatment is performed along the upward flow of the upward flow in the tank. Done. As a result, a floating oil layer S is formed above the oil / water interface X2, while a water layer is formed in the lower layer inside the tank. Then, the floating oil that has exceeded the upper edge of the drain gutter 8 flows into the drain gutter 8 and is discharged to the outside of the tank through the drain gutter 8, while the water in the lower layer inside the upflow separation tank is pushed by the oil liquid. It is discharged to the outside of the tank through the drainage pipe 9. In this way, the oil-water mixture poured from the stock solution inlet 3 undergoes the primary treatment in the downflow separation tank A1 and the secondary treatment in the upflow separation tank A2 to obtain a highly pure oil. And purified water to be recovered. Such purification is continuously carried out, and the stock solution flowing into the present apparatus can be continuously separated and collected into each purified solution. In the device of the present invention, in the downward flow separation tank having the function of the primary treatment tank, the flow of the liquid and the descending and settling direction of the water liquid, which is a high specific gravity liquid, coincide with each other, so the separation effect is extremely high. Are better.

<Test> In order to confirm the effect of this device, a test using the device shown in FIG. 1 was conducted. The test was conducted by sending an oil / water mixture prepared by adding 7,000 PPM of a water-soluble surfactant to a gear oil of 220 cst / 40 ° C to the device at a pump flow rate of 0.6 liter / min and collecting the oil in the oil collected by the device. When water content is measured and passed through this device only once, recovered oil is returned to the inlet side of this device to circulate inside this device and its processing time is changed. And were measured respectively. The oil temperature was 50 ° C., the amount of oil in the tank was 30 liters, and an alternating voltage of 25 V / 2 cm was applied to the charging plate. The results are shown in Table 1. During the test, the water separated during the treatment was continuously discharged outside the tank through the drainage pipe.

[0024]

[Table 1]

[0025]

[Effect of device]

 The two-liquid separation device of the present invention, such as an oil-water mixed liquid, has a primary treatment in the downflow separation tank, which uses the electric field action and the specific gravity difference while flowing the stock solution from above to below, and in the upflow separation tank. Combining the secondary treatments that use the difference in specific gravity performed while flowing the primary treatment liquid from the bottom to the top, in particular, the flow direction of the mixed solution in the primary treatment is defined as the downward flow, and that direction is the high specific gravity liquid. Since the direction of the descending sedimentation of the particles was made to coincide with that of the particles, the binding of the particles of the two liquids, such as the oil-water mixed solution in which a small amount of water was mixed in a large amount of oil, or the oil-water mixed solution which was emulsified by the mixture of the surfactant, was extremely Even if it is strong, it is possible to efficiently collect a highly purified liquid. Further, when a porous dielectric having a multi-electrode effect is interposed between the charging plates or a large number of charging plates are vertically installed in the upflow separation tank, the separation efficiency is further enhanced.

[Brief description of drawings]

FIG. 1 is a first embodiment of the present invention, in which (a) is a longitudinal sectional explanatory view and (b) is a lateral sectional explanatory view.

FIG. 2 is a second embodiment of the present invention, in which (a) is a longitudinal sectional explanatory view and (b) is a lateral sectional explanatory view.

FIG. 3 is a third embodiment of the present invention, in which (a) is a longitudinal sectional explanatory view and (b) is a lateral sectional explanatory view.

FIG. 4 is a fourth embodiment of the present invention, in which (a) is a vertical cross-sectional explanatory view and (b) is a horizontal cross-sectional explanatory view.

FIG. 5 shows a float suction, (a) is a plan view,
(B) is a front view

FIG. 6 is an explanatory longitudinal sectional view showing the outline of a conventional two-liquid separating device.

[Explanation of symbols]

A Tank body A1 Downflow separation tank A2 Upflow separation tank 1 Communication path 2 Partition plate 3 Undiluted solution inlet 4a, 4b Charging plate 4a ', 4b' Charging plate 5 Charging power source 6 Outer plate 7 Insulating plate 8 Oil drain trough 9 Drain Pipe 10 Pipe Tip Port 11 Water Storage Partition Plate 12 Level Adjuster 13a, 13b Charging Plate 14 Float Suction 15 Support Rod 16 Float 17 Suction Hose 18 Suction Port

Claims (5)

[Scope of utility model registration request] 1. A plurality of charging plates to which a voltage is applied are arranged to face each other, and an undiluted solution of a two-liquid mixed liquid continuously supplied from the outside of the apparatus is caused to flow downward between the charging plates in a downward direction. A down-flow separation tank for primary treatment, and an up-flow separation tank for communicating with the down-flow separation tank at the bottom and performing secondary treatment while floating the primary treatment liquid introduced through the communication passage from below to above. And a discharge port for the separated low specific gravity liquid on the upper side of the upflow separation tank and a discharge port for the separated high specific gravity liquid on the bottom side. Liquid separator. 2. A two-liquid separating apparatus for an oil-water mixed liquid or the like according to claim 1, wherein a plurality of charging plates to which a voltage is applied are vertically installed in an upflow separation tank. 3. A two-liquid separating apparatus for an oil / water mixed liquid according to claim 1, wherein a porous dielectric having a multi-electrode effect is interposed between the charging plates. 4. A charging voltage of 0.5 V to 3000 V /
A two-liquid separating device for an oil-water mixed liquid or the like according to claim 1, 2 or 3, wherein an AC voltage of cm is used. 5. A means for collecting a two-liquid mixed liquid in which a high specific gravity liquid is dispersed in a low specific gravity liquid floating in the upper layer of a stock solution tank,
A low specific gravity liquid is collected by using a float suction configured by attaching floats to three columns arranged at 120 ° angles, and in a state in which the set height of the suction port can be varied with reference to the two-liquid interface. A two-liquid separation device for the oil-water mixed liquid according to 1, 2, 3 or 4.