JP2007283276A - Electrolysis process and apparatus for it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel electrolysis process capable of obtaining a high treatment efficiency by electrolysis while effectively preventing sludge from accumulating in an electrolytic cell. <P>SOLUTION: The process comprises immersing each of at least a part of a plurality of electrode plates 3 placed vertically and in parallel in the electrolytic cell 1 in a liquid substance 2, forming a pair of first flows α of the liquid substance in a direction roughly perpendicular to a plane containing the electrode face 3c of the electrode plates 3 outside both the side parts 3L and 3R of the plurality of electrode plates 3, forming the second flow β of the liquid substance intersecting a plane containing the electrode face 3c of the electrode plates 3 below the plurality of electrode plates 3, supplying the liquid substance 2 to the electrolytic cell 1 by a pair of first flows α, and removing the liquid substance 2 from the electrolytic cell 1 by the second flow β. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for treating a liquid material, particularly a waste liquid containing heavy metal ions, by electrolysis.

  Electrolysis is widely used to treat various liquid materials for the purpose of reducing environmental burden, cost reduction, and reuse (see, for example, Patent Documents 1 to 3). In particular, wastewater containing heavy metal ions is treated by electrolysis, and the heavy metal is removed by separating the sludge into a metal hydroxide eluted from the anode together with the heavy metal in the form of an insoluble or sparingly soluble substance, so-called sludge. (For example, see Patent Documents 1 and 3).

  Conventionally, such an electrolysis process uses an aluminum electrode plate, and sludge containing the resulting aluminum hydroxide together with heavy metal is levitated using hydrogen gas bubbles generated at the cathode during electrolysis. It was common to separate them (see, for example, Patent Document 3).

  In the electrolysis process, it is desirable to prevent local consumption of the electrode plate and to easily separate and remove the generated sludge. Therefore, it has been proposed to agitate a liquid material, which is a liquid to be treated, in an electrolytic cell in place of the floating type as described above (see Patent Document 1).

JP-A-2005- 211768 JP 2004-81951 A Japanese Patent Laid-Open No. 7-116666

  When stirring the liquid material in the electrolytic cell, it is desirable to stir the liquid material with a stirring force that does not allow sludge to settle in the electrolytic cell (Patent Document 1). For example, if sludge is accumulated in the electrolytic cell, the electrode is buried in the sludge and cannot contact the liquid material, and there is a disadvantage that the effective electrolytic area of the electrode plate is reduced. However, if the stirring force is too strong, the progress of electrolysis is slowed, resulting in a decrease in processing efficiency. Until now, sufficient consideration has not been given to the flow state of the liquid in the electrolytic cell and the positional relationship between the components.

  An object of the present invention is to obtain high treatment efficiency by electrolysis while effectively preventing insoluble or hardly soluble substances such as sludge (hereinafter simply referred to as “sludge”) from accumulating in an electrolytic cell. It is an object of the present invention to provide a novel electrolysis treatment method and an apparatus therefor.

According to the first aspect of the present invention, at least a part of the plurality of electrode plates arranged substantially vertically and in parallel in the electrolytic cell is immersed in the liquid material, and the liquid material is treated by electrolysis. A method,
A pair of first flows of the liquid material is formed in a direction substantially perpendicular to a plane including the electrode surface of the electrode plate outside both sides of the plurality of electrode plates,
A second flow of liquid that intersects a plane including the electrode surface of the electrode plate is formed below the plurality of electrode plates, and the liquid is moved into the electrolytic cell by one of the first flow and the second flow. A method is provided that comprises providing and, with the other, extracting liquid from the electrolytic cell.

According to the electrolysis processing method of the present invention as described above, the pair of first flows flows outside both sides of the plurality of electrode plates, and the second flow flows below the plurality of electrode plates. Does not directly collide with the electrode surface of the electrode plate, thereby effectively preventing the progress of electrolysis. Further, the pair of first flows flows in directions substantially perpendicular to the plane including the electrode surfaces of the electrode plates outside both side portions of the plurality of electrode plates, and the second flow flows below the electrode plates. Since it flows in a direction intersecting with the plane including the surface, it is separated from the first flow that flows outside both sides of the electrode plate, descends through each of the two adjacent electrode plates, and flows under the electrode plate. A third flow of liquid material that naturally merges into the flow will naturally occur. Since the third flow is weaker than the first flow and the second flow and flows along the electrode surface of the electrode plate, not only does the progress of electrolysis be delayed, but also acts to update the electrode surface, The generated metal hydroxide or the like can be prevented from adhering to the electrode plate surface. As a result, it is possible to obtain high electrolysis processing efficiency.
In addition, according to the electrolysis processing method of the present invention, a pair of the first flow and the second flow are formed around the plurality of electrode plates, and the third flow is also formed between the electrode plates as described above. As a result, the liquid material can flow (or can be stirred) around the electrode plates and between the electrode plates, so that the electrolysis can be uniformly progressed for the electrode plates. Can be prevented from local consumption.
Furthermore, according to the electrolysis treatment method of the present invention, the liquid material is supplied to and extracted from the electrolytic cell while stirring the liquid material in the electrolytic cell as described above. , And can be discharged from the electrolytic cell, thereby effectively preventing sludge from accumulating in the electrolytic cell.

  Throughout the present invention, “substantially” in “substantially vertical” and “substantially vertical” means having a range that does not impair the operational effects of the present invention, for example, having a range of about ± 30 °. . Further, “both side portions” of the electrode plate means side portions located on the left and right sides toward the plate-like surface of the electrode plate. In addition, the “electrode surface” of the electrode plate means each surface facing two adjacent electrode plates, and the two “non-electrode surfaces” of the plurality of electrode plates are the plurality of electrode plates in a row. It means the surface located in the both ends of a row | line | column among all the plate-shaped surfaces. The “plane including the electrode surface of the electrode plate” means a virtual plane obtained by extending the electrode surface of the electrode plate.

  The flow rate of the first flow can be, for example, about 0.5 to 5.0 m / second, and preferably about 1.0 to 2.0 m / second. Further, the flow rate of the second flow can be, for example, about 0.5 to 5.0 m / second, and preferably about 1.0 to 2.0 m / second. By flowing the first flow and the second flow at such a flow rate, a sufficient stirring effect of the liquid can be obtained, and the local consumption of the electrode plate and the accumulation of sludge in the electrolytic cell are more effective. Can be prevented.

  Throughout the present invention, the “first flow velocity” and the “second flow velocity” are defined as the maximum flow velocity of the first flow and the second flow in the electrolytic cell, respectively. Therefore, “the flow velocity of the first flow” is “the maximum flow velocity of the flow in the region outside both sides of the plurality of electrode plates”, and “the flow velocity of the second flow” is “the region below the plurality of electrode plates”. Is the maximum flow velocity at. The location in the electrolytic cell where these “maximum flow velocity in the region outside both sides of the plurality of electrode plates” and “maximum flow velocity in the region below the plurality of electrode plates” are obtained It can be predicted in consideration of the shape, size, and arrangement of the tank and the electrode plate, and by measuring the flow velocity by using, for example, an ultrasonic current meter or an electromagnetic current meter at the predicted position, “ The “first flow velocity” and the “second flow velocity” may be determined.

  The plurality of electrode plates are arranged in parallel at an interval of, for example, about 10 to 50 mm, preferably about 20 to 30 mm. By arranging a plurality of electrode plates at such intervals, the liquid material can be appropriately passed from the first flow to between each of the two adjacent electrode plates to effectively generate the third flow. And high electrolysis treatment efficiency can be obtained. Such a plurality of electrode plates are generally arranged at equal intervals.

  However, it should be noted that the flow rates of the first flow and the second flow and the intervals between the plurality of electrode plates are not limited to the above ranges, and may vary depending on, for example, the viscosity of the liquid material to be processed and specific processing conditions. Should.

  The present invention is suitably used for treating wastewater containing heavy metal ions. The heavy metal ions co-precipitate when the metal ions eluted from the electrode plate of the anode form an insoluble or hardly soluble hydroxide to form sludge (which may contain a metal hydroxide and possibly a single metal). Sludge can be removed from the treated liquid by any appropriate solid-liquid separation method. Therefore, heavy metal ions can be separated from the wastewater in the form of sludge.

  In the present invention, the electrode plate is preferably made of iron (or a metal containing iron). Since iron forms a relatively heavy sludge with respect to the liquid phase of the liquid and tends to settle, the generated sludge should be quickly moved from the vicinity of the electrode plate by the third flow descending between two adjacent electrode plates. Can do. Further, iron is inexpensive, and has advantages such as a relatively low sludge moisture content and low disposal costs. However, the present invention is not limited to this, and the electrode plate may be made of a metal such as aluminum, magnesium, titanium, or an alloy containing at least one of them.

According to a second aspect of the present invention, there is provided an apparatus for treating a liquid material by electrolysis,
An electrolytic cell containing a liquid material;
A plurality of electrode plates disposed substantially vertically and in parallel in the electrolytic cell, and at least a portion of each of which is immersed in the liquid material;
In one side of the two non-electrode surfaces of the plurality of electrode plates, communicated with the inside of the electrolytic cell at a position corresponding to the outside of both sides of the electrode plates, and in a direction substantially perpendicular to the plane including the electrode surfaces of the electrode plates A pair of supply lines for supplying the liquid material into the electrolytic cell;
There is provided an apparatus comprising a discharge line communicating with the inside of the electrolytic cell below the electrode plate on the one side and for extracting a liquid material from the electrolytic cell.
The pair of supply lines can supply the liquid material into the electrolytic cell to form the pair of first flows, and the discharge line can form the second flow to extract the liquid material from the electrolytic cell. it can.

  In the apparatus of the present invention according to the second aspect, the wall surface and bottom surface of the electrolytic cell sequentially collide with the main flow of the liquid material supplied from the supply line, and the electrode surfaces of the electrode plates below the plurality of electrode plates. It can be arranged to function to produce a flow of liquid that intersects a plane containing the. Thereby, it is possible to obtain the second flow by changing the direction of the first flow, which is the main flow, with a very simple configuration.

  In one aspect of the present invention, the electrolysis processing apparatus is provided with means for generating a flow of a liquid material from the other side of the two non-electrode surfaces toward the one side below the plurality of electrode plates, for example, rotating blades or blades A stirrer equipped with a car or the like may be further provided. By such means, it is possible to enhance the second flow and promote the discharge of sludge.

  In the apparatus of the present invention according to the second aspect, the bottom surface of the electrolytic cell may be inclined so as to become lower as it approaches the discharge line. With such a configuration, it is possible to promote the discharge of sludge that can collect at the bottom of the electrolytic cell by the action of gravity.

According to a third aspect of the present invention, there is provided an apparatus for treating a liquid material by electrolysis,
An electrolytic cell containing a liquid material;
A plurality of electrode plates disposed substantially vertically and in parallel in the electrolytic cell, and at least a portion of each of which is immersed in the liquid material;
A tubular portion that extends from one side of the two non-electrode surfaces of the plurality of electrode plates to the other side, passes through the outside of both side portions of the electrode plate, and extends in a direction substantially perpendicular to the plane including the electrode surface of the electrode plate, and adjacent An opening provided in the tubular portion between each of the two electrode plates, the liquid is passed through the tubular portion from the one side to the other side, and supplied from the opening into the electrolytic cell. A pair of supply lines;
There is also provided an apparatus comprising a discharge line communicating with the inside of the electrolytic cell below the electrode plate on one side and for extracting a liquid material from the electrolytic cell.
The pair of supply lines can supply liquid material into the electrolytic cell to form the first pair of first flows, and the discharge line can form the second flow to remove the liquid material from the electrolytic cell. Can be extracted. Further, the third flow can be reliably formed by the openings of the pair of supply lines.

  In the apparatus of the present invention according to the third aspect, the tubular portions of the pair of supply lines pass outside the both sides of the plurality of electrode plates and pass through the electrolytic cell, and the opening tips are below the electrode plates. It may be inserted into the electrolytic cell so as to be located on the other side of the two non-electrode surfaces. Thereby, it is possible to change the direction of the first flow to the second flow with a simple configuration.

  Also in the apparatus of the present invention according to the third aspect, the bottom surface of the electrolytic cell may be inclined so as to become lower as it approaches the discharge line, and the above-described effects can be obtained.

According to a fourth aspect of the present invention, there is provided an apparatus for treating a liquid material by electrolysis,
An electrolytic cell containing a liquid material;
A plurality of electrode plates disposed substantially vertically and in parallel in the electrolytic cell, and at least a portion of each of which is immersed in the liquid material;
Supply that supplies liquid material into the electrolytic cell in a direction intersecting with the plane including the electrode surface of the electrode plate, communicating with the inside of the electrolytic cell below the electrode plate on one side of the two non-electrode surfaces of the plurality of electrode plates Line,
A discharge line that communicates with the inside of the electrolytic cell at a position corresponding to the inside of the two non-electrode surfaces of the two non-electrode surfaces of the plurality of electrode plates, and extracts the liquid material from the electrolytic cell;
The direction of the main flow of the liquid material supplied from the supply line is changed to a direction substantially perpendicular to the plane including the electrode surface of the electrode plate, and the outside of both sides of the plurality of electrode plates is There is also provided an apparatus comprising guide means which function to produce a flow of liquid passing toward one side.
The supply line can supply the liquid material into the electrolytic cell to form the second flow, the guide means can form the pair of first flows, and the discharge line can electrolyze the liquid material. Can be extracted from the tank.

  In the electrolysis treatment apparatus according to any of the gist of the present invention, the electrolytic cell may have a pair of side wall surfaces respectively opposed to both side portions of the plurality of electrode plates. By such a side wall surface, the first flow can be regulated and the third flow can be effectively generated.

  In any of the electrolysis treatment apparatuses according to the present invention, the discharge line is preferably connected to the supply line by a circulation line including a pump. Thereby, since the liquid substance extracted from the electrolytic cell can be supplied back into the electrolytic cell, the liquid substance can be efficiently supplied and discharged, and the treatment time by electrolysis can be arbitrarily set.

  The circulation line may be provided with a sensor for grasping the state of the liquid substance, such as a pH sensor, an electric conductivity meter, a turbidity meter, and the like. With such a sensor, it is possible to know the degree of progress of the uniform electrolysis of the liquid material in the electrolytic cell due to the stirring effect, and to manage the electrolysis process.

  The electrolysis processing apparatus according to any of the gist of the present invention as described above is preferably used for carrying out the electrolysis processing method of the present invention, and can achieve the same effects as the electrolysis processing method of the present invention.

  According to the electrolysis treatment method of the present invention, it is possible to obtain high treatment efficiency by electrolysis while effectively preventing sludge from accumulating in the electrolytic cell. Moreover, the electrolysis processing apparatus of this invention can be used suitably for implementing such a method.

  Three embodiments of the present invention will be described in detail below with reference to the drawings.

Embodiment 1
As shown in FIGS. 1 (a) and 1 (b) and FIG. 2, the electrolysis apparatus 30 in this embodiment includes an electrolytic cell 1, a plurality of electrode plates 3, a pair of supply lines 5L and 5R, and a discharge line 7. Prepare.

  A liquid material 2 is accommodated in the electrolytic cell 1, the plurality of electrode plates 3 are arranged substantially vertically and in parallel in the electrolytic cell 1, and at least a part of each is immersed in the liquid material 2.

In the present embodiment, wastewater containing heavy metal ions is used as the liquid material 2, but is not limited to this. Examples of the heavy metal ion include at least one ion selected from the group consisting of Cr ³⁺ , Mn ²⁺ , Mg ²⁺ , Fe ²⁺ , Fe ³⁺ , Zn ²⁺ , Ni ²⁺ and Mo ³⁺ . Such waste water can be, for example, washing water used to wash a metal object subjected to chemical conversion treatment which is a kind of metal surface treatment.

  The plurality of electrode plates 3 apply a voltage so as to alternately serve as an anode and a cathode during electrolysis. Therefore, the surfaces (that is, the first and last surfaces) 3a and 3b located at both ends of the row among all the surfaces of the electrode plates 3 forming a row are non-electrode surfaces, and any two adjacent electrode plates 3 Opposing surface 3c is an electrode surface.

  Each of the plurality of electrode plates 3 is a plate-like body made of a conductive material, such as iron, aluminum, magnesium, titanium, or an alloy containing at least one of them, preferably iron or an alloy containing iron. It is a plate-like body. In this embodiment, a metal plate made of iron is used regardless of whether it is an anode or a cathode. The metal plate made of iron is inexpensive, and has an advantage that sludge containing iron hydroxide, which will be described later, can be easily separated, and the cost for disposing of it is low.

  The plurality of electrode plates 3 are arranged in parallel at regular intervals, for example, at intervals s of about 10 to 50 mm, preferably about 20 to 30 mm. Such an interval between the electrode plates 3 is wider than an interval in an electrolysis apparatus generally used in the art. Each electrode plate 3 may have a thickness of about 2.0 to 3.0 mm, for example, and the size of the surface is not particularly limited, but may be about 20 to 120 cm in length × about 20 to 120 cm in width. The electrode plate 3 is not particularly limited. For example, about 10 to 20 electrode plates can be used. However, when the number of electrode plates 3 is increased, for example, it is conceivable to appropriately adjust the distance between the electrode plates so that the flow between the electrode plates is as uniform as possible.

  As shown in FIG. 1B, the plurality of electrode plates 3 are preferably exposed from a liquid material 2 at a portion connected to a power source (not shown), and most of each is immersed in the liquid material. By exposing the power connection part from the liquid 2, corrosion between different metals can be prevented. However, the present invention is not limited to this, and all of the plurality of electrode plates 3 may be immersed in the liquid material.

  As shown in the drawing, the electrolytic cell 1 is configured such that the side walls 1L and 1R of the electrolytic cell 1 are opposed to the side portions 3L and 3R of the electrode plate 3 with respect to the plurality of electrode plates 3, respectively. The Further, the electrolytic cell 1 is configured such that the wall surface of the side wall 1b located in front from the non-electrode surface 3a to 3b faces the non-electrode surface 3b. Further, the electrolytic cell 1 is configured such that the bottom surface of the bottom 1 c faces the lower end of the electrode plate 3.

  In this embodiment, the wall surface of the side wall 1L of the electrolytic cell 1 and the virtual plane including the end surfaces of the side portions 3L of the plurality of electrode plates 3 are substantially parallel, and the wall surface of the side wall 1R of the electrolytic cell 1 A virtual plane including the end surfaces of the side portions 3R of the plurality of electrode plates 3 is substantially parallel to each other, and two spaces having substantially equal widths are left therebetween (see FIG. 1A). ) In other words, the distance between the side wall 1L of the electrolytic cell 1 and the side 3L of the electrode plate 3 and the distance between the side wall 1R of the electrolytic cell 1 and the side 3R of the electrode plate 3 are both non-electrode surfaces 3a. To 3b. Moreover, the wall surface of the side wall 1b of the electrolytic cell 1 and the non-electrode surfaces 3b of the plurality of electrode plates 3 are substantially parallel, and a space having a substantially uniform width remains between them (FIG. 1A). And (b)). Further, the bottom surface of the bottom portion 1c of the electrolytic cell 1 and the virtual plane including the end surface of the lower end portion of the electrode plate 3 are substantially parallel, and a space having a substantially uniform width is left between them (see FIG. 1 (b)). However, these are not essential to the present invention as long as spaces are left around the plurality of electrode plates 3 in the electrolytic cell 1.

  The pair of supply lines 5L and 5R are on the non-electrode surface 3a side of the electrode plate 3, and communicate with the inside of the electrolytic cell 1 at positions corresponding to the outer sides of both side portions 3L and 3R of the electrode plate 3. Similarly, the discharge line 7 is on the non-electrode surface 3 a side of the electrode plate 3 and communicates with the inside of the electrolytic cell 1 below the electrode plate 3. The pair of supply lines 5 </ b> L and 5 </ b> R is preferably positioned near the liquid level below the liquid level of the liquid 2, and the discharge line 7 is positioned near the bottom surface of the bottom 1 c of the electrolytic cell 1.

  At least one of the pair of supply lines 5L and 5R and the discharge line 7 is connected to, for example, a pump or the like so that the liquid 2 can be supplied to and extracted from the electrolytic cell 1. The pump performance and the inner diameter of each line can be appropriately selected so as to obtain a desired flow state. The pair of supply lines 5L and 5R may be provided with means for controlling the flow of the liquid 2 to be supplied, such as nozzles and automatic valves. In order to facilitate the extraction of the liquid material 2, the discharge line 7 may be provided with a hood (for example, as provided in the discharge line 47 of FIG. 10) or the like at the opening located in the electrolytic cell 1.

  The electrolytic cell 1, the supply lines 5L and 5R, and the discharge line 7 are preferably made of a material having at least an inner surface having corrosion resistance. The electrolytic cell 1 is preferably made of a material having at least an inner surface having electrical insulation properties from the viewpoint of preventing accidents such as electric leakage. The supply lines 5L and 5R and the discharge line 7 may be either electrically conductive (for example, metal) or electrically insulating (for example, resin), but the inner surface thereof is preferably made of a material that is difficult to adhere sludge.

  In the present embodiment, the electrolytic cell 1, the plurality of electrode plates 3, the pair of supply lines 5L and 5R, and the discharge line 7 are symmetrical with respect to the central plane MM shown in FIG. Although preferably arranged, this is not essential.

  In the present embodiment, the pair of supply lines 5L and 5R and the discharge line 7 are used. However, a plurality of pairs of supply lines and a plurality of discharge lines may be used. preferable. It is also possible to use each line by appropriately switching it with a switching valve or the like.

  Using such an electrolysis processing apparatus 30, the liquid 2 can be processed by electrolysis as follows.

  First, the liquid 2 is supplied from the pair of supply lines 5L and 5R into the electrolytic cell 1 in a direction substantially perpendicular to the plane including the electrode surface of the electrode plate 3, while being liquid from the electrolytic cell 1 from the discharge line 7. Pull out object 2. Thereby, the flow of the liquid material 2 is formed in the electrolytic cell 1.

  More specifically, when the liquid 2 is supplied from a pair of supply lines 5L and 5R in a direction substantially perpendicular to the plane including the electrode surface of the electrode plate 3, most of the liquid material 2 is provided on the side walls 1L and 1R of the electrolytic cell 1. It flows through the space between the wall surface and the side portions 3L and 3R of the electrode plate 3. Thus, a pair of first flows α that flow in directions substantially perpendicular to the plane including the electrode surface 3c of the electrode plate 3 are formed as main flows outside the both side portions 3L and 3R of the electrode plate 3. A part flows under the restriction of the side walls 1L and 1R, and flows around each of the two adjacent electrode plates 3 and into a region in front of the non-electrode surface 3a.

  The first flow α collides with the wall surface of the front side wall 1b, passes through the space between the wall surface of the side wall 1b of the electrolytic cell 1 and the non-electrode surface 3b of the electrode plate 3, and then collides with the bottom surface of the bottom portion 1c. Then, it passes through the space between the wall surface of the bottom 1 c of the electrolytic cell 1 and the lower end of the electrode plate 3, flows across the electrode surface of the electrode plate 3, and is extracted from the discharge line 7. Thereby, the 2nd flow (beta) which cross | intersects the plane containing the electrode surface of the electrode plate 3 below the electrode plate 3 is formed.

  In addition, the flow that flows from the pair of first flows α flowing on the left and right of the electrode plate 3 to the gap between the two adjacent electrode plates 3 flows below the electrode plate 3 and crosses the electrode surface. Since it is attracted to the flow β, a third flow γ descending this gap naturally occurs.

  The first flow α and the second flow β are relatively strong flows. The flow rate of the first flow α can be set to, for example, about 0.5 to 5.0 m / second, preferably about 1.0 to 2.0 m / second. Moreover, the flow rate of the second flow β can be set to, for example, about 0.5 to 5.0 m / second, preferably about 1.0 to 2.0 m / second. On the other hand, the third flow γ is a relatively weak flow.

  In the present embodiment, preferably, a flow state that is symmetric with respect to the central plane MM shown in FIG.

  Then, under such a flow state (or agitation state) of the liquid material 2, a predetermined voltage is applied to a plurality of electrode plates 3 from a power source (not shown) so that they alternately serve as an anode and a cathode. Apply. By applying voltage, the opposing electrode surfaces of two adjacent electrode plates function as a pair of electrodes, and the electrolysis reaction proceeds.

  Through the electrolysis reaction, metal ions are eluted from the electrode plate 3 of the anode and react with the hydroxide ions in the liquid to form a metal hydroxide, in this embodiment, iron hydroxide. Although depending on the pH, iron hydroxide is insoluble in water that constitutes most of the liquid material, and co-precipitates heavy metal ions in the liquid material to form sludge. In short, the metal ions eluted from the electrode plate 3 of the anode function as a precipitating agent (or a coagulating precipitant) with respect to the heavy metal ions. On the other hand, hydrogen gas can be generated from the cathode electrode plate 3.

  The relatively strong first flow α and second flow β do not directly collide with the electrode surface 3 c of the electrode plate 3. In addition, the relatively weak third flow γ does not directly collide with the electrode surface 3 c of the electrode plate 3. The third flow γ flows along the electrode surface 3 c and acts to update the electrode surface 3 c, and the generated sludge is quickly removed from the vicinity of the electrode plate 3. By these, an electrolysis reaction can be advanced efficiently.

  In particular, the sludge containing iron hydroxide as generated in the present embodiment tends to settle in the liquid material, and thus is easily removed by the descending third flow γ.

  Further, the liquid material 2 can be sufficiently stirred around the electrode plate 3 by the relatively strong first flow α and second flow β and the relatively weak third flow. Thereby, an electrolysis reaction can be made to advance uniformly about the some electrode plate 3, As a result, local consumption of the electrode plate 3 can be prevented.

  In order to make the consumption of the electrode plate 3 uniform, it is preferable to carry out the electrolysis process while controlling the applied voltage so as to exchange the anode and the cathode. However, the present invention is not limited to this, and voltage may be applied without exchanging the anode and the cathode. In this case, plate-like bodies made of different materials may be used for the anode and the cathode. For example, the anode can be made of iron, and the cathode can be made of corrosion resistant, highly ionizable metals, alloys and other electrically conductive materials.

  Thereafter, the sludge removed by the third flow γ is entrained in the second flow β and extracted from the electrolytic cell 1 together with the liquid 2 through the discharge line 7. Since the liquid material 2 is sufficiently stirred in the electrolytic cell 1 by the relatively strong first flow α, the second flow β and the relatively weak third flow γ, sludge is accumulated in the electrolytic cell 1. Can be effectively prevented.

  As described above, the liquid 2 is processed by electrolysis, and heavy metal ions contained in the liquid 2 can be captured in the form of sludge. The sludge containing heavy metal can be removed from the treated liquid 2 by any appropriate solid-liquid separation method such as sedimentation separation, flotation separation, filtration, or the like.

  According to the present embodiment, the present invention can be effectively implemented with a very simple configuration. The electrolysis treatment of the present embodiment may be carried out either batchwise or continuously.

  This embodiment can be variously modified. For example, in the present embodiment, the side walls 1L and 1R are substantially parallel with the wall surfaces of the side walls 1L and 1R of the electrolytic cell 1 and the virtual plane including the end surfaces of the side portions 3L and 3R of the plurality of electrode plates 3 being substantially parallel. Although the distances between the side portions 3L and 3R are made uniform over the non-electrode surfaces 3a to 3b, the side walls 1L and 1R of the electrolytic cell 1 are connected to the side portions 3L and 3R of the plurality of electrode plates 3, respectively. You may make it incline with respect to the virtual plane containing these end surfaces. In this case, as shown in FIG. 3, the distance between the side wall 1L ′ of the electrolytic cell 1 and the side 3L of the electrode plate 3 and the distance between the side wall 1R ′ of the electrolytic cell 1 and the side 3R of the electrode plate 3 are used. It is preferable that all the distances are configured to gradually become shorter from the non-electrode surfaces 3a to 3b. By appropriately adjusting the inclination angle, the flow velocity of the first flow α of the liquid 2 supplied from the supply lines 5L and 5R can be maintained substantially constant over the non-electrode surfaces 3a to 3b. The flow state (including the first flow α, the second flow β, and the third flow γ) of the liquid 2 with respect to the plurality of electrode plates 3 can be made more uniform.

  Moreover, as shown in FIG. 4, you may further provide the stirrer 9 in which the rotary blade was inserted below the electrode plate 3 by the non-electrode surface 3b side. The stirrer 9 generates a flow of the liquid material 2 from the non-electrode surface 3b toward the non-electrode surface 3a below the plurality of electrode plates 3, thereby enhancing the second flow β. In this case, the stirring by the stirrer 9 is appropriate according to the dimensions and arrangement of the electrolytic cell and the electrode so that the enhanced second flow β is not excessive and delays the progress of electrolysis. Should be limited to Instead of the stirrer 9, for example, a vibration stirrer or the like may be used.

  Further, as shown in FIG. 5, the discharge line 7 ′ is provided on the bottom 1c ′ of the electrolytic cell 1 on the non-electrode surface 3a side, and is inclined so as to become lower as the bottom surface of the bottom 1c ′ approaches the discharge line 7 ′. You may let them. Thereby, relatively heavy sludge containing iron hydroxide can be collected toward the discharge line 7 ′ by the action of gravity and can be effectively extracted from the electrolytic cell 1. Thereby, discharge of the sludge from the electrolytic cell 1 can be promoted.

  Moreover, as shown in FIG. 6, it is preferable that the discharge line 7 is connected to the supply line 5 by the circulation line 8 in which the pump P is inserted. Thereby, supply and discharge | emission of a liquid substance can be implemented efficiently, and the processing time by electrolysis can be set arbitrarily. The circulation line 8 may be provided with a sensor that grasps the state of the liquid substance (for example, the degree of treatment by electrolysis) (not shown in FIG. 6). Examples of such a sensor include a pH sensor, an electric conductivity meter, and a turbidity meter. Thereby, it is possible to know the degree of progress of electrolysis of the liquid 2 that has been sufficiently stirred and made uniform in the electrolytic cell 1, and the electrolysis process can be managed.

  In order to electrolyze waste water containing heavy metal ions to obtain water containing no metal ions, pH is particularly important. Heavy metal ions can be trapped in the sludge and removed from the liquid phase as the pH value of the liquid phase of the liquid is higher, but if the pH value is too high, a large amount of iron ions of the anode will be present in the liquid phase. . Therefore, in order to reduce both heavy metal ions and iron ions in the liquid phase, it is preferable to control the voltage application based on the measured pH value so that the pH is maintained at, for example, 6-7.

  Further, for example, as shown in FIG. 7, the untreated liquid material may be transferred to the electrolytic cell 1 through a line 11a, and the treated liquid material may be transferred from the electrolytic cell 1 through a line 11b. By using such lines 11a and 11b, the treatment by electrolysis can be carried out batchwise or continuously. The configuration in which the line 11b as shown in the figure transports the liquid material by overflow is suitable for carrying out the electrolysis process continuously.

  In addition, as shown in FIG. 8, for example, the liquid material after treatment is transferred from the line 11b to the mixing tank 21a and mixed with slaked lime supplied from the line 11c, and the resulting mixture is statically mixed in the settling tank 21b. The sludge 17 can be settled and separated. The sludge 17 can be taken out from the sedimentation tank 21b to the tank 29 by draining. On the other hand, the liquid phase 19 from which the sludge 17 has been substantially removed can be taken out from the line 11d as a supernatant layer. Here, slaked lime is mixed to make the liquid after treatment alkaline, to promote hydroxide formation, and to coagulate and settle sludge that does not easily settle (for example, calcium phosphate). The alkaline liquid phase 19 thus obtained can be suitably used as washing water or the like for degreasing metal objects such as electrodeposition coating.

  Alternatively, the treated liquid material is transferred to the floating tank 21c from the line 11b and supplied to the lower part of the floating tank 21 through the nozzle 23 as shown in FIG. The sludge is floated by compressed air mixed in the liquid. The sludge 17 floating on the liquid level in the floating tank 21c can be scraped off by, for example, an arm 27 that reciprocates and taken out to the tank 29 '. On the other hand, the liquid phase 19 from which the sludge 17 has been substantially removed can be taken out from the line 11e as a lower layer.

When the electrode plate 3 made of iron is used as in the present embodiment, a relatively heavy sludge containing iron hydroxide is generated. Therefore, it is preferable to use a method using sedimentation separation as described with reference to FIG. Is done.
In this embodiment, it is also possible to use an electrode plate made of aluminum instead of the electrode plate 3 made of iron. In this case, since a relatively light sludge containing aluminum hydroxide is generated, one using floating separation as described with reference to FIG. 9 is preferably applied. Further, in this case, sludge can be separated from the liquid material after the treatment by filtering with a filter such as a paper filter in addition to floating separation.
However, the method of separating the sludge from the electrode plate material and the liquid material is not limited to these combinations.

  The circulation line 8 in FIGS. 8 and 9 may be provided with a strainer 13 or a filter upstream of the pump P, so that the pump P can be protected from dusts and blisters that may be contained in the liquid material. The circulation line 8 may be provided with the sensor 15a and / or the flow meter 15b as described above for grasping the state of the liquid material. The degree of processing by electrolysis can be grasped by the sensor 15a, and electrolysis can be controlled based on this. Further, the flow rate flowing through the circulation line 8 can be measured by the flow meter 15b to confirm that the pump P is operating normally. The flow meter 15b may be a flow switch, and may be configured to automatically control the device to issue a warning when the flow rate falls below a predetermined flow rate or to stop the operation. These can be applied to the electrolytic treatment apparatus described with reference to FIGS. 6 and 7 as well.

  Although only the supply line 5 is shown in the electrolysis treatment apparatuses 31 to 37 in FIGS. 4 to 9, the description has been given with reference to FIGS. 1A and 1B and FIG. 2 unless otherwise specified. This is the same as the supply lines 5L and 5R in the electrolysis treatment apparatus 30.

Embodiment 2
As shown in FIGS. 10A and 10B, in the electrolysis processing apparatus 40 in the present embodiment, each of the pair of supply lines 45L and 45R has a tubular portion 45a and an opening 45b. The tubular portion 45 a passes outside the both side portions 3 L and 3 R of the plurality of electrode plates 3, penetrates the electrolytic cell 1, and is routed outside the electrolytic cell 1, so that the opening tip 45 c is below the electrode plate 3. And inserted in the electrolytic cell 1 so as to be located on the non-electrode surface 3b side. The tubular portion 45 a is provided with an opening 45 b so as to be positioned between the two adjacent electrode plates 3. A flow rate adjusting valve 49 can be provided in a portion of the tubular portion 45a located outside the electrolytic cell 1. As shown in the drawing, the opening front end portion 45c is preferably inclined toward the discharge line 47, but is not limited thereto. About the other point, unless there is particular notice, the description similar to the above-mentioned Embodiment 1 is applicable.

  In the present embodiment, the electrolytic cell 1, the plurality of electrode plates 3, the pair of supply lines 45L and 45R, and the discharge line 47 are symmetrical with respect to the central plane MM shown in FIG. Although preferably arranged, this is not essential. 10A shows a cross-sectional view of the distal end portion 45c of the tubular portion 45a of the supply line 45R viewed from the YY direction in FIG. 1B.

  Using such an electrolysis processing apparatus 40, the liquid 2 is passed through the tubular portions 45a of the pair of supply lines 45L and 45R to flow from the non-electrode surface 3a side to the non-electrode surface 3b side, and the opening portion. It is fed into the electrolytic cell 1 from 45b and from the opening tip 45c. The liquid 2 is extracted from the electrolytic cell 1 through the discharge line 47.

  Thus, the first flow α is formed through the tubular portions 45a of the pair of supply lines 45L and 45R, and the second flow β is formed below the electrode plate 3. In addition, the third flow γ can be reliably formed between the two adjacent electrode plates 3 by the liquid material 2 flowing out from the opening 45b. Furthermore, the tubular portion 45a penetrates the electrolytic cell 1, is routed outside the electrolytic cell 1, and the opening tip 45c is inserted into the electrolytic cell 1, so that the first flow can be achieved with a simple configuration. The direction of α can be changed to the second flow β.

  The inner diameters of the tubular portion 45a and the opening 45b can be appropriately selected so that a desired flow state is obtained. For example, the third flow γ separated from the first flow α can be made uniform by setting the inner diameter of the tubular portion 45a sufficiently large and appropriately setting the inner diameter of the opening 45b. Further, the flow rate of the second flow β can be adjusted by using the flow rate adjusting valve 49.

  Various modifications can be made to the second embodiment as described above. For example, modifications similar to those described in the first embodiment with reference to FIGS. 4 to 9 can be made.

Embodiment 3
As shown in FIGS. 11A and 11B, the electrolysis processing apparatus 50 in the present embodiment includes a pair of supply lines 55L and 55R, a pair of discharge lines 57L and 57R, and guide members 59a and 59b. The pair of supply lines 55 </ b> L and 55 </ b> R are on the non-electrode surface 3 a side of the plurality of electrode plates 3 and communicate with the inside of the electrolytic cell 1 below the electrode plates 3. Further, the pair of discharge lines 57L and 57R are on the non-electrode surface 3b side of the electrode plate 3, and communicate with the inside of the electrolytic cell 1 at positions corresponding to the inner sides of both side portions 3L and 3R of the electrode plate 3. . The pair of supply lines 55L and 55R are preferably positioned near the bottom surface of the bottom 1c of the electrolytic cell 1, and the pair of discharge lines 57L and 57R are preferably positioned near the liquid level below the liquid level of the liquid 2. The guide member 59a is positioned in contact with the wall surface of the side wall 1b of the electrolytic cell 1 and immediately below the discharge lines 57L and 57R, and the guide member 59b is positioned in contact with the side wall 1b and the bottom 1c of the electrolytic cell 1. About the other point, unless there is particular notice, the description similar to the above-mentioned Embodiment 1 is applicable.

  In the present embodiment, the electrolytic cell 1, the plurality of electrode plates 3, the pair of supply lines 55L and 55R, the pair of discharge lines 57L and 57R, and the guide members 59a and 59b have a central plane M shown in FIG. Although preferably arranged so as to be symmetrical with respect to −M, this is not essential.

  Using such an electrolysis processing apparatus 50, the liquid material 2 is supplied into the electrolytic cell 1 through a pair of supply lines 55L and 55R in a direction crossing a plane including the electrode surface 3c of the electrode plate 3. The liquid 2 is extracted from the electrolytic cell 1 through the discharge lines 57L and 57R.

  As a result, the second flow β that flows across the plane including the electrode surface of the electrode plate 3 below the electrode plate 3 is formed as the main flow. Then, the second flow β collides with the guide member 59b, passes through the space between the wall surface of the side wall 1b of the electrolytic cell 1 and the non-electrode surface 3b of the electrode plate 3, and then collides with the guide member 59a. The direction is substantially perpendicular to the plane including the electrode surface of the plate 3, and passes through both sides 3 L and 3 R of the plurality of electrode plates 3 from the non-electrode surface 3 b side to the non-electrode surface 3 a side. 1 flow α is generated. A part of the first flow α wraps around the gap between the two adjacent electrode plates 3, is attracted to the second flow β that flows across the electrode surface below the electrode plate 3, and descends the gap. 3 flow γ naturally occurs. A part of the liquid 2 colliding with the guide member 59a goes around the guide member 59a and is extracted from the discharge lines 57L and 57R.

  Various modifications can be made to the third embodiment as described above. For example, modifications similar to those described in the first embodiment with reference to FIGS. 6 to 9 can be made.

  Although the three embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and may be implemented in a wide variety of ways without departing from the concept of the present invention.

  The electrolysis treatment method and apparatus of the present invention are, for example, flush water used for washing an object subjected to chemical conversion treatment which is a kind of metal surface treatment applied to an automobile body or the like (see, for example, Patent Documents 1 and 3). Can be processed by electrolysis. Moreover, it can utilize for processing the waste_water | drain (For example, refer patent document 2) containing a phosphorus component by electrolysis. In addition to these, any liquid material can be used as long as electrolysis is performed.

It is the schematic which shows the electrolysis processing apparatus in one Embodiment of this invention, Comprising: Fig.1 (a) is a top view, FIG.1 (b) is sectional drawing seen from the XX direction of Fig.1 (a). It is. It is a schematic perspective view of the electrolysis processing apparatus in the embodiment of FIG. It is the schematic which shows one modification of the electrolysis processing apparatus in embodiment of FIG. 1, Comprising: It is a figure corresponding to Fig.1 (a). It is the schematic which shows another modification of the electrolysis processing apparatus in embodiment of FIG. 1, Comprising: It is a figure corresponding to FIG.1 (b). It is the schematic which shows another modification of the electrolysis processing apparatus in embodiment of FIG. 1, Comprising: It is a figure corresponding to FIG.1 (b). It is the schematic which shows another modification of the electrolysis processing apparatus in embodiment of FIG. 1, Comprising: It is a figure corresponding to FIG.1 (b). It is the schematic which shows another modification of the electrolysis processing apparatus in embodiment of FIG. 1, Comprising: It is a figure corresponding to FIG.1 (b). It is the schematic which shows another modification of the electrolysis processing apparatus in embodiment of FIG. 1, Comprising: It is a figure corresponding to FIG.1 (b). It is the schematic which shows another modification of the electrolysis processing apparatus in embodiment of FIG. 1, Comprising: It is a figure corresponding to FIG.1 (b). It is the schematic which shows the electrolysis processing apparatus in another embodiment of this invention, Comprising: Fig.10 (a) is a top view, FIG.10 (b) is the cross section seen from the XX direction of Fig.10 (a). FIG. It is the schematic which shows the electrolysis processing apparatus in another embodiment of this invention, Comprising: Fig.11 (a) is a top view, FIG.11 (b) is the cross section seen from the XX direction of Fig.11 (a). FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrolytic cell 1L, 1R, 1L ', 1R', 1a, 1b Side wall 1c, 1c 'Bottom part 2 Liquid substance 3, 3' Electrode plate 3L, 3R Side part 3a, 3b Non-electrode surface 3c Electrode surface 5, 5L, 5R , 45L, 45R, 55L, 55R Supply line 7, 7 ', 7L, 7R, 47, 57L, 57R Discharge line 8 Circulation line 9 Stirrer 11a, 11b, 11c, 11d, 11e line 13 Strainer 15a pH sensor 15b Flow meter 17 Sludge 19 Liquid phase 21a Mixing tank 21b Sedimentation tank 21c Flotation tank 23 Nozzle 25 Bubble 27 Arm (scraper)
29, 29 'Tank 30, 31, 32, 33, 34, 35, 36, 37, 40, 50 Electrolytic treatment device 45a Tubular part 45b Opening part 45c Opening tip part 49 Flow control valve 59a, 59b Guide member P Pump α First flow β Second flow γ Third flow

Claims (17)

A method of immersing at least a part of a plurality of electrode plates disposed substantially vertically and in parallel in an electrolytic cell in a liquid material, and treating the liquid material by electrolysis,
A pair of first flows of the liquid material is formed in a direction substantially perpendicular to a plane including the electrode surface of the electrode plate outside both sides of the plurality of electrode plates,
A second flow of liquid that intersects a plane including the electrode surface of the electrode plate is formed below the plurality of electrode plates, and the liquid is moved into the electrolytic cell by one of the first flow and the second flow. Feeding and extracting the liquid from the electrolytic cell by the other.   The method according to claim 1, wherein the flow rate of the first flow is 0.5 to 5.0 m / sec.   The method according to claim 1 or 2, wherein the flow rate of the second flow is 0.5 to 5.0 m / sec.   The method according to claim 1, wherein the plurality of electrode plates are arranged in parallel at an interval of 10 to 50 mm.   The method in any one of Claims 1-4 whose said liquid substance is the waste_water | drain containing a heavy metal ion.   The method according to claim 1, wherein the electrode plate is made of iron. An apparatus for treating a liquid material by electrolysis,
An electrolytic cell containing a liquid material;
A plurality of electrode plates disposed substantially vertically and in parallel in the electrolytic cell, and at least a portion of each of which is immersed in the liquid material;
In one side of the two non-electrode surfaces of the plurality of electrode plates, communicated with the inside of the electrolytic cell at a position corresponding to the outside of both sides of the electrode plates, and in a direction substantially perpendicular to the plane including the electrode surfaces of the electrode plates A pair of supply lines for supplying the liquid material into the electrolytic cell;
An apparatus comprising a discharge line communicating with the inside of the electrolytic cell below the electrode plate on the one side and for extracting a liquid material from the electrolytic cell.   The wall surface and bottom surface of the electrolytic cell sequentially collide with the main flow of the liquid material supplied from the supply line, and the flow of the liquid material that intersects the plane including the electrode surface of the electrode plate below the plurality of electrode plates is generated. The apparatus of claim 7, configured as follows.   The apparatus according to claim 7 or 8, further comprising means for generating a flow of liquid material from the other side of the two non-electrode surfaces toward the one side below the plurality of electrode plates. An apparatus for treating a liquid material by electrolysis,
An electrolytic cell containing a liquid material;
A plurality of electrode plates disposed substantially vertically and in parallel in the electrolytic cell, and at least a portion of each of which is immersed in the liquid material;
A tubular portion that extends from one side of the two non-electrode surfaces of the plurality of electrode plates to the other side, passes through the outside of both side portions of the electrode plate, and extends in a direction substantially perpendicular to the plane including the electrode surface of the electrode plate, and adjacent An opening provided in the tubular portion between each of the two electrode plates, the liquid is passed through the tubular portion from the one side to the other side, and supplied from the opening into the electrolytic cell. A pair of supply lines;
An apparatus comprising a discharge line communicating with the inside of the electrolytic cell below the electrode plate on the one side and for extracting a liquid material from the electrolytic cell.   The tubular portions of the pair of supply lines pass through the outer side of the plurality of electrode plates and pass through the electrolytic cell so that the opening tips are located on the other side of the two non-electrode surfaces below the electrode plates. The apparatus according to claim 10, wherein the apparatus is inserted into an electrolytic cell.   The apparatus in any one of Claims 7-11 in which the bottom face of an electrolytic cell inclines so that it may become lower as it approaches a discharge line. An apparatus for treating a liquid material by electrolysis,
An electrolytic cell containing a liquid material;
A plurality of electrode plates disposed substantially vertically and in parallel in the electrolytic cell, and at least a portion of each of which is immersed in the liquid material;
Supply that supplies liquid material into the electrolytic cell in a direction intersecting with the plane including the electrode surface of the electrode plate, communicating with the inside of the electrolytic cell below the electrode plate on one side of the two non-electrode surfaces of the plurality of electrode plates Line,
A discharge line that communicates with the inside of the electrolytic cell at a position corresponding to the inside of the two non-electrode surfaces of the two non-electrode surfaces of the plurality of electrode plates, and extracts the liquid material from the electrolytic cell;
The direction of the main flow of the liquid material supplied from the supply line is changed to a direction substantially perpendicular to the plane including the electrode surface of the electrode plate, and the outside of both sides of the plurality of electrode plates is And a guide means which functions to produce a flow of liquid passing toward one side.   The apparatus in any one of Claims 7-13 with which an electrolytic cell has a pair of side wall surface which respectively opposes the both sides of a several electrode plate.   The device according to any of claims 7 to 13, wherein the discharge line is connected to the supply line by a circulation line comprising a pump.   The apparatus according to claim 15, wherein a sensor for grasping a state of the liquid substance is provided in the circulation line.   The apparatus according to any one of claims 7 to 16, which is used for carrying out the method according to any one of claims 1 to 6.

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