JP4546329B2 - Electrolyzer hose connection jig and electrolyzer unit - Google Patents

Description

  The present invention relates to an electrolytic cell hose connection treatment used when an alkali chloride aqueous solution is electrolyzed by an ion exchange membrane method and a nozzle of a collecting pipe for supplying or discharging a liquid to or from an electrolytic cell for an electrolyzer is connected to the outside. And an electrolyzer unit.

  Ion-exchange membrane method alkaline electrolysis, which produces alkali hydroxide, chlorine, and hydrogen industrially by electrolyzing an aqueous alkali chloride solution, is a low-energy alkali hydroxide with high purity compared to conventional methods such as the diaphragm method and the mercury method. Since it is obtained by consumption, it is widely used today.

In this method, as shown in FIG. 4, two cells 1 and 2 containing an aqueous sodium chloride solution are separated from each other by a cation exchange membrane 3, and current is passed to generate chlorine on the anode side and hydrogen on the cathode side. To do. Further, since only the ion exchange membrane permeates Na ⁺ ions, caustic soda can be obtained on the cathode side. Therefore, as a hose attached and used at the inlet and outlet on the anode side and the cathode side in contact with these products, conventionally, the hose has a high degree of reliability with excellent heat resistance, chemical resistance, pressure tightness and bending resistance. A fluororesin hose is used. In FIG. 4, reference numeral 4 indicates an anode, and reference numeral 5 indicates a cathode. A sodium chloride aqueous solution is supplied from an inlet 6 and discharged from an outlet 7.

  FIG. 7 shows an external view of an electrolytic cell for electrolyzing the alkali chloride aqueous solution. Reference numeral 11 in the figure indicates an electrolytic cell body. A hydraulic cylinder 13 and a rear head 14 for moving the loose head 12 are provided on one side of the electrolytic cell main body 11. A catholyte inlet sub-header 14 for supplying the catholyte is provided. Inside the loose head 12, a terminal cell 15 that functions as an anode is disposed adjacently. The end cell 15 is fixed to the side plate 17 by an arm 16. A fixed head 18 is disposed on the other side of the electrolytic cell main body 11, and a terminal cell 19 that functions as a cathode is disposed adjacent to the fixed head 18. The end cell 19 is fixed to the side plate 16 by an arm 17.

  A bipolar cell 21 suspended by a cell hanger 20 is set in the electrolytic cell main body 11. In the vicinity of the electrolytic cell main body 11, a catholyte inlet sub-header 22 for supplying the catholyte to the electrolytic cell main body 11, an anolyte inlet sub-header 23 for supplying the anolyte, a catholyte outlet sub-header 24, And an anolyte outlet subheader (not shown). A nozzle (not shown) of each subheader such as the catholyte inlet subheader 22 and the electrolytic cell body 11 are connected by a fluororesin hose 25. Here, since fluororesin hoses come into contact with products such as chlorine gas, hydrogen gas, caustic soda, etc., high reliability with excellent heat resistance, chemical resistance, pressure tightness and bending resistance has been achieved. What you have is used. In addition, the number 26 in a figure shows the nut for fastening.

  By the way, as a connection method for connecting the electrolytic cell main body and the nozzle of the sub header, a flange portion is formed at the hose end by transfer molding, high frequency welding, spin welding, hot air welding, high frequency induction heating, bad weld, etc. A method (Patent Document 1) (see FIG. 3) in which the electrolytic cell and the subheader are tightened and sealed with a cap nut is proposed and adopted. In FIG. 3, reference numeral 31 indicates a nozzle welded to the subheader 32. A hose 33 is attached to one end of the nozzle 32 via an O-ring 34. An auxiliary electrode 35 is attached to the nozzle 31 by welding in order to prevent electrolytic corrosion of the nozzle 31. The hose 33 is fixed to the tip of the nozzle 31 by a cap nut 36 screwed into the nozzle 32.

Moreover, like patent document 2, by fitting the diameter-expansion part of a tube to the protrusion part of a joint main body, and screwing in and tightening a nut to a joint main body in that state, the pulling-out resistance of a tube is increased and a hose is stuck to a protrusion part. A cup joint method is known. Further, as disclosed in Patent Document 3, a resin that can ensure high sealing performance, can smoothly screw a pipe fastening member, and can prevent tube disconnection and liquid leakage without requiring additional tightening. Pipe joints have also been proposed.
JP 2000-127190 A JP 2003-269673 A JP 2001-317679 A

  However, as in Patent Document 1, a hose is formed by transfer molding or the like at the end of the hose, and the flange is sealed by tightening an O-ring to the electrolytic cell or subheader nozzle with a cap nut. In order to form a flange at the end, a dedicated facility, a mold, and the like are required, and the number of manufacturing steps is also great. Of course, the molded flange is made of the same fluororesin material as the hose, so if it is used repeatedly, the shape may change due to creep, stress relaxation, etc., which may affect the service life of the hose. There is.

  Further, as described above, the auxiliary electrode is attached to the nozzle in order to prevent electrolytic corrosion of the nozzle. However, since the auxiliary electrode is attached to the nozzle and then attached to the flanged hose, it is difficult to confirm the progress of corrosion of the auxiliary electrode.

  The present invention has been made in consideration of such circumstances, and since the nipple can be used as an auxiliary electrode, the progress of corrosion can be confirmed appropriately during operation, and dust, metal components, which are problematic in chemical plants, etc. An electrolytic cell hose connection jig and an electrolysis apparatus unit that can eliminate nipples, exchange nipples easily and in a short time, contribute to prevention of contamination of the work environment and reduction of work time, etc. For the purpose.

  The hose connection jig for an electrolytic cell according to the present invention is for an electrolytic cell used when connecting a nozzle of a collecting pipe for supplying or discharging a liquid to an electrolytic cell for an electrolysis apparatus that electrolyzes an aqueous alkali chloride solution and the outside. In the hose connection jig, one end is located at the tip of the nozzle, the other part is inserted and arranged inside the hose, and a first taper surface is formed on the outer peripheral part into which the hose is inserted. Further, a nipple having a function as an auxiliary electrode, a first nipple surface of the nipple is disposed outside the first hose, and the inner periphery of the nipple is in contact with the first taper surface of the nipple via the hose. A ring having a two-tapered surface, and a cap nut screwed to the outer periphery of the nozzle and joined to the ring to fix the hose together with the nipple. And wherein the door.

  An electrolyzer unit according to the present invention includes an electrolyzer for an electrolyzer equipped with a nozzle for a collecting pipe for supplying or discharging a liquid, a hose connecting jig for an electrolyzer according to claim 1, and the hose for an electrolyzer. And an electrolytic cell hose connected to the nozzle using a connecting jig.

  According to the present invention, since the nipple can be used as an auxiliary electrode, it is possible to confirm the progress of corrosion as appropriate during operation, and to eliminate generation of dust and metal powder, which is a problem in chemical plants and the like. it can. Further, conventionally, when the auxiliary electrode has deteriorated due to corrosion, it has been necessary to remove the connection portion such as welding and perform welding again. However, in the present invention, the nipple functioning as the auxiliary electrode has a hose connection treatment. Since it is one configuration of the tool, the nipple can be exchanged easily and in a short time, which contributes to prevention of contamination of the work environment and shortening of the work time.

Hereinafter, the present invention will be described in more detail.
Examples of the fluororesin hose used in the present invention include, but are not limited to, tetrafluoroethylene resin (PTFE), modified tetrafluoroethylene resin, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin. (PFA), a tetrafluoroethylene-hexafluoropropylene copolymer resin (PFEP) hose. The hose must be able to withstand chemical resistance against chlorine gas, hydrogen gas, caustic soda, etc., which is a product of a salt water electrolyzer, and heat resistance of about 90 ° C., which is the temperature of these chemicals. .
The material of the cap nut used in the present invention is not limited to this, but usually, for example, titanium or stainless steel can be used.

  As a material of the nipple used in the present invention, in order to provide a function as an auxiliary electrode together with a role for connecting a hose, on the anode side, for example, pure titanium or oxide such as titanium, ruthenium, iridium on the titanium surface is used. For example, nickel or stainless steel is desirable on the coated or cathode side. Here, an oxide is formed on the anode-side titanium surface for the purpose of preventing corrosion of the titanium material and ensuring durability. This oxide also has a purpose of reducing the voltage of minute electrolysis generated at both ends of the fluororesin hose 25 in FIG. 7 when acting as a sacrificial electrode.

  Examples of the ring material used in the present invention include, but are not limited to, titanium and stainless steel. In addition, as shown in FIG. 2, it is advantageous in terms of safety and the creep resistance of the tube that the ring is shaped so as to cover the hose portion inserted into the nipple in a wide area. It can be adopted.

  In the hose connection jig of the present invention, the inclination angle (θ) of each tapered surface formed on the outer peripheral portion of the nickel and the inner peripheral portion of the ring is fixed by sandwiching the tube between the tapered surface portions of the nipple and the nozzle. From the viewpoint of preventing detachment, the range of 5 ° to 15 ° is preferable. Here, if the inclination angle is less than 5 °, the hose may come out of the tapered surface portion of the nipple due to the action of pressure applied to the inside of the hose. In addition, when tightening with a nut, a long tightening length is required, and the nut and subheader become large. When the inclination angle exceeds 15 °, the expansion ratio of the hose inner diameter increases, which affects the durability of the hose, such as a buckling crack of the hose, and causes a decrease in reliability.

Next, specific embodiments of the electrolytic cell hose connection jig according to the present invention will be described.
(Embodiment 1)
This will be described with reference to FIG. Reference numeral 41 in the figure indicates a subheader as a collective pipe. A nozzle 42 having a counterbore 42a formed at the tip is connected to the sub header 41 by welding. A nipple 43 having a flange 43a is disposed on a spot facing 42a at the tip of the nozzle via an O-ring 44 for sealing the hose end. Here, the nipple 43 has a function as an auxiliary electrode, and a first tapered surface 43b inclined at about 10 ° with respect to the axial direction is formed on the outer peripheral portion to which the hose 45 is attached.

  A ring 46 is inserted into the tapered surface portion of the nipple 43 through the hose 45. Here, a second tapered surface 46 a is formed on the inner peripheral portion of the ring 46 so as to contact the tapered surface 43 b of the nipple 43 via the hose 45. The inclination angle of the second tapered surface 46a is the same as that of the first tapered surface 43b. A cap nut 47 that is joined to the ring 46 and fixes the hose 45 together with the nipple 43 is screwed onto the outer periphery of the nozzle 42.

(Embodiment 2)
Please refer to FIG. However, the same members as those in FIG. The electrolytic cell hose connection jig according to Embodiment 1 is different in the shape of the ring 48 from the connection jig of FIG. That is, as shown in FIG. 2, the ring 48 has a long shape so as to cover the hose portion inserted into the nipple 43 in a wide area. In the case of the connecting jig of FIG. 2, the ring 48 covers the hose portion in a wider area, which is advantageous in terms of safety and creep resistance of the tube.

Next, specific examples of the present invention will be described.
Example 1
This will be described with reference to FIG. In FIG. 1, only one end of the hose is shown for convenience. In Example 1, titanium cap nuts 47 and stainless steel rings 46 are attached to both ends of a hose 45 made of PFA resin (trade name: AP-230 manufactured by Daikin Industries, Ltd.) having an outer diameter of 9 mm, an inner diameter of 6 mm, and a length of 1200 mm. After passing, the both ends of the hose 45 are heated and softened with a hot air generator, a titanium body obtained by cutting is coated with a chloride such as ruthenium, titanium, iridium, and then the nipple 43 is heat-treated in the atmosphere. The hose 45 was pushed into both ends, and finally the cap nut 47 was screwed into the thread portion of the nozzle 42.

  The electrolytic cell hose connection jig according to Example 1 is arranged with a nozzle 42 having a counterbore 42a formed at the tip, and an O-ring 44 at the tip of the nozzle 42, and about 10 ° on the outer periphery. The first tapered surface 43b inclined to the nipple 43 has a function as an auxiliary electrode, and the second tapered surface 46a is formed on the inner peripheral portion of the nipple 43 inserted into the tapered surface portion. A ring 46 and a cap nut 47 that is screwed onto the outer periphery of the nozzle 42 and fixes the hose 45 together with the nipple 43 are provided.

  With such a hose connection jig, the metal nipple 43 is press-fitted or inserted into the PFA resin hose 45, and the PFA resin hose 45 with the hose connection jig is assembled only by tightening the ring 46 and the cap nut 47. It is possible, and production efficiency can be greatly improved. In the case of normal temperature processing, since the thermal history is not received, the properties of the PFA resin hose 45 are maintained, and deterioration such as strength reduction does not occur.

  In the case of Example 1, the joint parts can be assembled and assembled in a total of 40 minutes, including the time required for cutting the stainless steel ring and nipple, and the time required for heating the hose end and inserting the nipple. there were.

  The hose 45 may not be expanded but may be forcibly pressed after heating the nipple 43 having the function of an auxiliary electrode to room temperature or a temperature below the melting point of the fluororesin that is the material of the hose.

(Example 2)
This will be described with reference to FIG. In FIG. 2, only one end of the hose is shown for convenience. As shown in FIG. 2, as the stainless steel ring, a PFA resin (manufactured by Daikin Industries, Ltd.) is used with the same connecting jig as in Example 1 except that the ring 48 having a shape covering the entire hose portion inserted into the nipple is used. AP-230) Both ends of the hose were fixed.
In the case of the electrolytic cell hose connection jig of Example 2, the ring 48 is shaped to cover the hose portion inserted into the nipple in a wide area, which is advantageous in terms of safety and creep resistance of the tube. . As a matter of course, the time for assembling the hose using the hose connecting jig was the same as in Example 1.

(Comparative example)
This will be described with reference to FIG. In this comparative example, after inserting a cap nut 36 into a PFA resin (trade name: AP-230, manufactured by Daikin Industries, Ltd.) having an outer diameter of 9 mm, an inner diameter of 6 mm, and a length of 1200 mm, a flange molding metal is formed at one end. A mold is mounted, PFA resin (product name: AP-230 manufactured by Daikin) is loaded inside the mold, heated to the melting temperature of the PFA resin or higher with an electric heater, and pressure is applied using an air cylinder above the mold. Was added. Thereafter, the electric heater was turned off and cooled with compressed air to form the flange portion 33a. Next, the flange part was formed in the opposite end part of the PFA resin hose by the same method, and the PFA resin hose having the structure shown in FIG. 3 provided with the flange part and the cap nut 1 at both ends was obtained. In the case of this comparative example 1, it took 70 minutes to form the flange portions on both sides of the hose.

  In the case of the comparative example, flange portions are formed at both ends of the fluororesin hose, and heating for a long period of time is necessary until the fluororesin melts. In addition, since the fluororesin itself is exposed to a high temperature above its melting point for a long time, it cannot be denied that changes in physical properties such as strength degradation due to thermal degradation of the resin occur. Specifically, in the case of this comparative example, it took 70 minutes to form the flange portions on both sides of the hose.

Next, using the electrolytic cell hose connection jig prepared in Examples 1 and 2 and the comparative example, the test apparatus shown in FIG. 5 and FIG. -A removal durability test was conducted. In FIG. 5, reference numeral 51 indicates a hot water tank in which water 50 is accommodated. In the hot water tank 51, a through-hole non-test sub-header 52 and a through-hole test sub-header 53 are connected by a PFA resin hose 54 using an electrolytic cell hose connection jig. A pipe 56 having a pressure gauge 55 interposed is connected to the sub header 53. 5 and 6 indicates an electric heater, and reference numeral 58 in FIG. 6 indicates a hydraulic pump. Table 1 below shows the results of the airtight test, and Tables 2 and 3 below show the results of the durability test.

Test Method / Condition: As shown in FIG. 5, one end of each type of PFA resin hose 54 is sealed and the other end is connected to a state where compressed air can be introduced. After holding the entire PFA resin hose 54 in the hot water tank 51 for 10 minutes, compressed air is introduced from the pipe 56, and gradually increased from 0.2 Mpa to 0.6 Mpa in units of 0.2 Mpa. The pressure was held for 5 minutes. This cycle was repeated three times, and the airtight state for each cycle was observed.

Test Method / Condition: As shown in FIG. 6, one end of each type of PFA resin hose 54 is in a sealed state, the other end is connected to a state where pressurized water can be introduced, and 0.1 MPa by a hydraulic pump 58 The test was carried out 50 times by holding the entire PFA resin hose 54 in a 90 ° C. hot water tank 51 for 5 minutes, leaving it removed for 5 minutes, and then applying a water pressure of 0.1 MPa again. The degree of deformation of the resin hose 54 was confirmed.

  Test method and conditions: As shown in FIG. 6, one end of each type of PFA resin hose 54 is sealed and the other end is connected to a state where compressed air can be introduced. After holding the whole PFA resin hose 54 in the water tank 51 for 10 minutes, it was introduced from one side by a hydraulic pump 58 and the pressure was increased until the PFA resin hose 54 was broken. After the breakage, the degree of deformation of the joint portion was confirmed.

  From the above results, compared with the electrolytic cell hose connection jig by the method of the comparative example manufactured by the conventional method, the durability of the electrolytic cell hose connection jig of Example 1 and Example 2 according to the present invention, The sealability is excellent and proved to be highly reliable. In addition, as described in the examples and comparative examples, the joint method of the first and second examples according to the present invention greatly reduces the number of manufacturing steps compared to the method of forming the flange portion with the resin of the comparative example. It is possible to significantly reduce the cost.

Example 4
An electrolytic decomposition apparatus unit according to the present invention includes an electrolytic tank for an electrolysis apparatus provided with a nozzle of a collecting pipe for supplying or discharging a liquid, a hose connection jig for an electrolytic tank according to claim 1, and the electrolytic cell hose. And an electrolytic cell hose connected to the nozzle using a connecting jig. Here, the nozzle is, for example, the nozzle 42 shown in FIGS. 1 and 2. The electrolyzer electrolytic cell is an electrolytic cell as shown in FIG. 7, for example. The electrolytic cell hose connection jig is, for example, the connection jig described in FIGS. 1 and 2, and includes a nozzle 42, a nipple 43, a ring 46, and a cap nut 47. The electrolytic layer hose is, for example, the PFA resin hose 45 shown in FIGS.

  According to the electrolyzer unit having such a configuration, the progress of corrosion can be confirmed even during operation, and generation of dust and metal powder, which is a problem in a chemical plant, etc., can be eliminated. Can be exchanged, and can contribute to prevention of contamination of the working environment and shortening of working time.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, you may combine suitably the component covering embodiment.

Sectional drawing of the hose connection jig for electrolytic vessels which concerns on one embodiment of this invention. Sectional drawing of the hose connection jig for electrolytic vessels which concerns on other embodiment of this invention. Sectional drawing of the hose connection jig for electrolytic vessels which concerns on a comparative example. The principle figure by the electrolyzer for electrolyzers. Schematic of an airtight test device. Schematic of a durability test apparatus. The external view of the electrolytic cell for electrolyzers.

Explanation of symbols

  41 ... Subheader (collection piping), 42 ... Nozzle, 43 ... Nipple, 43a ... Flange, 43b, 46a ... Tapered surface, 44 ... O-ring, 45 ... Hose, 46, 48 ... Ring, 47 ... Cap nut, 51 DESCRIPTION OF SYMBOLS ... Warm water tank, 52 ... Sub header for no through hole test, 53 ... Sub header for test with through hole, 54 ... PFA resin hose, 55 ... Pressure gauge, 56 ... Pipe, 57 ... Electric heater, 58 ... Water pressure pump.

Claims (4)

In the electrolytic cell hose connection jig used when connecting the outside of the nozzle of the collecting pipe for supplying or discharging the liquid to the electrolytic cell for the electrolyzer that electrolyzes the aqueous alkali chloride solution,
As an auxiliary electrode, one end is located at the tip of the nozzle, the other part is inserted and arranged inside the hose, and a first tapered surface is formed on the outer peripheral part into which the hose is inserted. A nipple having a function, and a second tapered surface that is disposed outside the first tapered surface of the nipple via the hose and is in contact with the first tapered surface of the nipple via the hose And a cap nut that is screwed onto the outer peripheral portion of the nozzle and is joined to the ring to fix the hose together with the nipple. 2. The electrolytic cell hose connection jig according to claim 1, wherein an O-ring as a seal member is disposed between the tip of the nozzle and the nipple. 3. The electrolytic cell hose connection jig according to claim 1, wherein the nipple is made of any one of metal titanium, metal nickel, or an alloy of these metals. Electrolyzer for electrolysis apparatus provided with nozzle of collecting pipe for supplying or discharging liquid, hose connecting jig for electrolytic cell according to claim 1, and connected to the nozzle using this hose connecting jig for electrolytic cell An electrolytic cell unit comprising an electrolytic cell hose.

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