JP4514705B2 - Waste liquid treatment equipment - Google Patents

Description

  The present invention relates to a waste liquid treatment apparatus, and more particularly to a waste liquid treatment apparatus for treating a waste liquid containing an alcohol component.

  Conventionally, as a device for removing alkali components and volatile acid components from waste liquid containing alkali components and volatile acid components discharged from a factory that manufactures electronic components and the like, a wastewater treatment device as disclosed in Patent Document 1 It has been known.

  As shown in FIG. 3, a wastewater treatment apparatus disclosed in Patent Document 1 includes a raw water tank 101 that stores waste liquid containing alkali components and volatile acid components, and a deaerator 102 that removes alkali components in the waste liquid. And an evaporator 103 for evaporating and condensing the waste liquid.

In order to remove the alkaline component and the volatile acid component from the waste liquid using the wastewater treatment apparatus 100 configured as described above, first, water is used so that the pH of the waste liquid stored in the raw water tank 101 is 4 to 5. Sodium oxide is fed into the waste liquid to produce the sodium salt of the volatile acid component. Next, after removing the alkaline component in the waste liquid in the deaerator 102, the waste liquid is evaporated and concentrated in the evaporator 103, the water vapor generated in the evaporator 103 is condensed and recovered as condensed water, and volatile. The sodium salt of the acid component is recovered as a concentrate.
JP 2002-143850 A

  However, when the wastewater treatment apparatus disclosed in Patent Document 1 is used to treat waste liquid containing an alcohol component in addition to an alkali component and a volatile acid component, the alcohol component is contained in water vapor generated in the evaporator. Had the problem of migrating. As a result, the condensed water obtained by condensing the water vapor generated in the evaporator contains an alcohol component, and it is difficult to reuse this condensed water or to drain it as it is.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a waste liquid treatment apparatus that can efficiently and reliably treat a waste liquid containing an alcohol component in particular.

  The above object of the present invention is a waste liquid treatment apparatus for treating a waste liquid containing an alkali component, a volatile acid component, and an alcohol component, wherein the waste liquid is heated and evaporated by mixing an acid that neutralizes the alkali component. An evaporation device that generates and discharges a vapor containing a volatile acid component and an alcohol component while leaving a Japanese salt, and condenses the vapor discharged from the evaporation device to mainly contain an acid-containing condensation containing a volatile acid component. A condensing device for separately producing water and alcohol-containing condensed water mainly containing an alcohol component, and an alcohol separating device for separating the alcohol component from the alcohol-containing condensed water produced by the condensing device. The apparatus includes a steam introduction chamber into which the steam discharged from the evaporator is introduced, and the steam introduced into the steam introduction chamber is introduced through the first heat transfer tube. In addition, a first storage chamber for storing the condensed water generated in the first heat transfer tube, steam introduced into the first storage chamber is introduced via the second heat transfer tube, and the second heat transfer tube A second storage chamber for storing the condensed water generated in step (b), and the steam passing through the first heat transfer tube is included in the steam by heat exchange with cooling water for cooling the outer surface of the first heat transfer tube. The alcohol-containing condensate in which the volatile acid component dissolved is converted into the remaining alcohol-containing steam from which the volatile acid component has been removed from the steam, and the alcohol-containing steam passing through the second heat transfer tube is the second It is converted into alcohol-containing condensed water by heat exchange with cooling water that cools the outer surface of the heat transfer tube, and the alcohol separator guides the condensed water from which the alcohol component has been separated to the condenser as the cooling water. Waste liquid treatment configured as It is achieved by the device.

  In this waste liquid treatment apparatus, the alcohol separation device is preferably an aeration device that vaporizes alcohol components from the condensed water by spraying the alcohol-containing condensed water under reduced pressure.

  Moreover, it is preferable to provide the alcohol absorber which makes the alcohol component isolate | separated with the said alcohol separator contact the solution for a dissolution, and is dissolved.

  The condensing device includes a storage can that stores cooling water, and a spraying device that sprays the cooling water stored in the storage can on the outer surfaces of the first heat transfer tube and the second heat transfer tube, By exchanging heat between the steam passing through the first heat transfer tube and the second heat transfer tube and the cooling water sprayed on the outer surfaces of the first heat transfer tube and the second heat transfer tube, the first heat transfer tube and the second heat transfer tube 2. At least a part of the steam generated by evaporation of the cooling water on the outer surface of the heat transfer tube is supplied to the evaporator as a heating source for generating steam including a volatile acid component and an alcohol component in the evaporator. It is preferable to be configured to be able to.

  The condensing device includes an alkaline liquid supply device that supplies an alkaline liquid for neutralization to the acid-containing condensed water generated in the first heat transfer tube, and an alkaline liquid and an acid content that are supplied from the alkaline liquid supply device. It is preferable that the apparatus further includes a reflux unit that introduces condensed water that is generated by a neutralization reaction of condensed water and contains neutralized salt stored in the first storage chamber to the storage can as the cooling water.

  ADVANTAGE OF THE INVENTION According to this invention, the waste liquid processing apparatus which can process the waste liquid containing especially an alcohol component efficiently and reliably can be provided.

  A waste liquid treatment apparatus for treating a waste liquid containing an alkali component, a volatile acid component, and an alcohol component according to the present invention will be described with reference to the accompanying drawings. In addition, ammonia can be illustrated as an alkali component contained in a waste liquid, and formic acid, acetic acid, etc. can be illustrated as a volatile acid component. Examples of the alcohol component include methyl alcohol (methanol) and ethyl alcohol (ethanol). FIG. 1 is a schematic configuration diagram of a waste liquid treatment apparatus according to an embodiment of the present invention. As shown in FIG. 1, the waste liquid treatment apparatus 1 includes a PH adjustment device 10, an ejector 15, an evaporation device 20, a first condensation device 40, a second condensation device 70, an alcohol separation device 80, and an alcohol absorption device 90. .

  The PH adjusting device 10 is a device that adjusts the pH of the waste liquid by neutralizing an alkali component such as ammonia dissolved in the waste liquid supplied from a waste liquid tank (not shown) to generate a neutralized salt. The PH adjusting device 10 includes a storage tank 11, an acid supply device 12, and a waste liquid supply conduit 13. The storage tank 11 is a tank that stores waste liquid containing an alkali component, a volatile acid component, and an alcohol component supplied from a waste liquid tank (not shown). The acid supply device 12 is a device that supplies an acid for neutralization into the storage tank 11, and an acid storage section 12 a that stores acid and an acid supply path 12 b that guides the acid in the acid storage section 12 a to the storage tank 11. And. The waste liquid supply pipe 13 is a pipe that guides the waste liquid mixed with the neutralizing acid in the storage tank 11 to the evaporator 21 of the evaporator 20.

  As the acid supplied from the acid supply device 12, an acid capable of generating a neutralized salt by neutralizing an alkali component in the waste liquid is employed. When the alkaline component in the waste liquid is, for example, ammonia, for example, sulfuric acid, hydrochloric acid, nitric acid, or the like can be employed as the acid supplied from the acid supply device 12. In particular, it is preferable to employ sulfuric acid from the viewpoint of producing a neutralized salt with low metal corrosivity.

  The ejector 15 is a vapor compression means for sucking and compressing the vapor, and extends to the vapor suction side 16 from the vapor supply line 18 through which the vapor supplied from a vapor supply source (not shown) and the first condensing device 40 flow. A steam reuse line 44 is connected. Further, a steam supply line 19 for heating that guides the steam compressed by the ejector 15 to the evaporator 20 is connected to the discharge side 17 of the ejector 15.

  The evaporator 20 heats and evaporates the waste liquid mixed with the neutralizing acid in the PH adjusting apparatus 10, thereby generating a concentrated liquid in which the neutralized salt remains, and a vapor containing a volatile acid component and an alcohol component. , A device for discharging the steam. The evaporator 20 includes a sealed evaporator 21, a waste liquid spraying device 22, an indirect heater 23, a steam transfer conduit 24, and a condensed water drain conduit 25.

  The bottom part of the evaporator 21 constitutes a storage part for storing waste liquid mixed with the neutralizing acid supplied from the PH adjusting device 10.

  The waste liquid spraying device 22 is a supply device that supplies the waste liquid stored at the bottom of the evaporator 21 toward the outer surfaces of the plurality of heat transfer tubes 29. The waste liquid sprayer 22 is disposed on the top of the evaporator 21 and sprays the waste liquid. A spray nozzle 26 and a waste liquid circulation pipe 27 that connects the waste liquid spray nozzle 26 and the bottom of the evaporator 21 are provided. A circulation pump 27 a that guides the waste liquid stored at the bottom of the evaporator 21 to the waste liquid spray nozzle 26 is provided in the middle of the waste liquid circulation pipe 27. The waste liquid circulation line 27 is connected to a concentrated liquid discharge line 28 for discharging the concentrated liquid accumulated at the bottom of the evaporator 21 at the end of the evaporative concentration process.

  The indirect heater 23 includes a plurality of heat transfer tubes 29 provided inside the evaporator 21, and a first header 30 and a second header 31 respectively connected to both ends of the plurality of heat transfer tubes 29. . Connected to the first header 30 is a heating steam supply pipe 19 that guides the steam compressed by the ejector 15 to the heat transfer pipe 29. Connected to the second header 31 is a heating steam discharge pipe 32 that guides the steam led from the first header 30 through the heat transfer pipe 29 to a second condensing device 70 described later.

  The vapor transfer line 24 is a line that discharges the vapor containing the volatile acid component and the alcohol component generated in the evaporation device 20 and guides the vapor to the heat exchanger 43 of the first condensing device 40 described later. 21 and the first header 51 constituting the heat exchanger 43 of the first condensing device 40 are connected.

  The condensed water drain conduit 25 is a conduit for discharging condensed water accumulated in the second header 31 of the indirect heater 23, one end of which is connected to the lower portion of the second header 31, and the other end will be described later. It is connected to the condensed water discharge pipe 72.

  The first condensing device 40 condenses the vapor containing the volatile acid component and the alcohol component discharged from the evaporation device 20, and contains the acid-containing condensed water mainly containing the volatile acid component and the alcohol containing mainly the alcohol component. It is a device that generates condensed water. The first condensing device 40 includes a sealed storage can 41 for storing cooling water therein, a heat exchanger 43, a cooling water spraying device 42, an alkaline liquid supply device 60, a steam reuse pipe 44, and a condensed water reflux pipe. A path 45, an alcohol-containing condensed water supply line 46 and an alcohol-containing steam supply line 47 are provided.

  The heat exchanger 43 includes a plurality of heat transfer tubes 50 provided in the storage can 41, and a first header 51 and a second header 52 connected to both ends of the plurality of heat transfer tubes 50, respectively. The plurality of heat transfer tubes 50 are arranged along the vertical direction. The inside of the first header 51 is partitioned by a partition member 53 to form a steam introduction chamber 51a and a second storage chamber 51b, and steam can be introduced so that steam discharged from the evaporator 20 can be introduced into the steam introduction chamber 51a. A transfer line 24 is connected to the first header 51. Moreover, the inside of the 2nd header 52 comprises the 1st storage chamber 52a. The first storage chamber 52a is a storage space for storing the condensed water generated by the first heat transfer tube 501, and the second storage chamber 51b is a storage space for storing the condensed water generated by the second heat transfer tube 502. is there.

  Thus, by partitioning the inside of the first header 51 into the steam introduction chamber 51a and the second storage chamber 51b, the steam discharged from the evaporation device 20 and guided to the first header 51 as described later is the steam introduction chamber. After being introduced into 51a and guided to the first storage chamber 52a via the first heat transfer tube 501 as shown by arrow A, the second heat transfer tube 502 is used as shown by arrow B. 2 It will be guide | induced to the storage chamber 51b.

  The cooling water spraying device 42 is a device that supplies the cooling water stored in the bottom of the storage can 41 toward the outer surfaces of the plurality of heat transfer tubes 50 and cools the outer surfaces of the heat transfer tubes 50. The cooling water spraying device 42 is disposed in the upper portion of the storage can 41 and sprays a cooling water spray nozzle 48 that sprays the cooling water, and a cooling water circulation pipe that connects the cooling water spray nozzle 48 and the bottom of the storage can 41. 49. A circulating pump 49 a that guides the cooling water stored at the bottom of the storage can 41 to the cooling water spray nozzle 48 is provided in the middle of the cooling water circulation pipe 49. The cooling water circulation pipe 49 is connected to a cooling water discharge pipe 54 for discharging the cooling water stored at the bottom of the storage can 41 to the outside.

  The alkaline liquid supply device 60 is a device that sprays a neutralizing alkaline liquid into the first heat transfer tube 501. The alkaline liquid supply device 60 includes an alkaline liquid tank 61 that stores the alkaline liquid, an alkaline liquid supply pipe 62, and an unillustrated alkaline liquid spray nozzle that sprays the alkaline liquid. The alkaline liquid spray nozzle is installed in the vapor transfer line 24. In addition, the installation position of this alkaline liquid spray nozzle is not specifically limited, For example, the structure installed in the vapor | steam introduction chamber 51a of the 1st header 51 is also employable.

  Further, the alkaline liquid supply device 60 is configured to be able to control the spray amount of the alkaline liquid based on the cooling water PH stored in the storage can 41 of the first condensing device 40. Specifically, it is configured to include an opening / closing valve 66 that controls the amount of alkaline liquid to be sprayed based on the measured value of the PH monitor 65 installed in the cooling water circulation pipe 49 constituting the cooling water spraying device 42. ing. The PH monitor 65 is a detection device that measures the pH of the cooling water stored in the storage can 41 and passing through the cooling water circulation line 49. The on-off valve 66 includes a motor M, and by driving the motor M, the opening degree of the on-off valve 66 can be adjusted to control the amount of the alkaline liquid to be sprayed.

  The neutralizing alkaline liquid sprayed from the alkaline liquid supply device 60 is to neutralize a volatile acid component contained in the vapor led from the evaporation device 20 to the first condensing device 40 to generate a neutralized salt. An alkaline solution that can be used is adopted. When the volatile acid component is, for example, formic acid, for example, an aqueous sodium hydroxide solution or an aqueous calcium hydroxide solution can be employed as the alkaline solution. In particular, from the viewpoint of producing a neutralized salt having high solubility, it is preferable to employ an aqueous sodium hydroxide solution as the alkaline solution.

  As will be described later, the steam reuse pipe 44 is a heating source for generating at least part of the steam generated by the first condensing device 40 and generating steam containing a volatile acid component and an alcohol component in the evaporator 20. As shown in the figure, it is a conduit for supplying to the evaporation device 20, and connects the upper portion of the storage can 41 and the suction side 16 of the ejector 15. Further, a condensing steam pipe 67 connected to a second condensing device 70 described later is provided in the middle of the steam reuse pipe 44.

  The condensed water reflux pipe 45 is a pipe that is generated in the first heat transfer pipe 501 and guides the condensed water stored in the first storage chamber 52a to the storage can 41 as cooling water. The can 41 is connected.

  The alcohol-containing condensate supply pipe 46 is a pipe that guides the condensate generated in the second heat transfer pipe 502 and stored in the second storage chamber 51b to an alcohol separation device 80 described later. The bottom and the alcohol separator 80 are connected.

  The alcohol-containing steam supply pipe 47 is a pipe that guides the steam that has not been condensed in the second heat transfer pipe 502 to the alcohol absorber 90 described later, and connects the upper part of the second storage chamber 51b and the alcohol absorber 90. ing.

  The second condensing device 70 is a device that generates condensed water by cooling and condensing the steam guided from the evaporator 20 and the first condensing device 40, and the steam reuse pipe 44 of the first condensing device 40. A condensing steam pipe 67 extending from the cooling water, a cooling water supply pipe 71 through which the cooling water is guided, and a condensed water discharge pipe 72 for discharging the generated condensed water to the outside. As the cooling water guided to the second condensing device 70 through the cooling water supply pipe 71, industrial water cooled by a cooling tower (not shown) or the like, cold water (chiller water) cooled by a refrigerating device, or the like can be used. In the middle of the condensed water discharge pipe 72, a makeup water pipe 73 connected to the bottom of the storage can 41 of the first condenser 40 is connected, and the condensed water generated in the second condenser 70 is first condensed. The bottom of the storage can 41 of the device 40 is configured to be recirculated and replenished. In addition, a condensed water drain line 25 extending from the lower part of the second header 31 of the evaporator 20 is connected to the condensed water discharge line 72.

  The alcohol separation device 80 vaporizes and separates the alcohol component from the alcohol-containing condensed water generated by the first condensing device 40, and stores the can of the first condensing device 40 using the condensed water from which the alcohol component has been separated as cooling water. 41 is configured to be led to 41. In FIG. 1, the case where an aeration apparatus is employ | adopted as the alcohol separation apparatus 80 is illustrated. This aeration apparatus is an apparatus that vaporizes alcohol components from condensed water by spraying the alcohol-containing condensed water under reduced pressure, and is led through an alcohol-containing condensed water supply pipe 46 as shown in FIG. A condensate spray device 81 for spraying condensate containing the alcohol component, an aeration tower 82 in which the condensate spray device 81 is installed, and an alcohol-containing steam supply pipe for separating the gaseous alcohol component separated from the condensate The inside of the aeration tower 82 is depressurized, the alcohol transfer pipe 83 that leads to the path 47, the separated water supply pipe 84 with a transfer pump that leads the condensed water from which the alcohol component has been separated to the storage can 41 of the first condenser 40, and the aeration tower 82. Pressure reducing means 85. An example of the decompression means 85 is a suction pump.

  The alcohol absorbing device 90 is a device that dissolves the vapor containing the alcohol component led from the first condensing device 40 and the alcohol component led from the alcohol separation device 80 in contact with the dissolving liquid, and stores the dissolving liquid. A washing tower 92 having a washing room 91 and a dissolving liquid spraying device 93 are provided. The washing tower 92 is connected to the alcohol-containing steam supply pipe 47 so that the steam containing the alcohol that has not been condensed in the first condenser 40 and the alcohol component separated by the alcohol separator 80 can be introduced. It is configured. The dissolving liquid spraying device 93 includes a dissolving liquid spraying nozzle 94 and a dissolving liquid circulation conduit 95 so that the dissolving liquid stored in the washing tower 92 can be sprayed from the dissolving liquid spraying nozzle 94. It is configured. The dissolution liquid circulation line 95 includes a cooling device 96 that cools the dissolution liquid flowing inside. Examples of the solution for dissolution include pure water and alcohol water.

  A method of treating a waste liquid containing an alkali component, a volatile acid component, and an alcohol component using the waste liquid treatment apparatus 1 configured as described above will be described below. In order to facilitate understanding of the treatment method, the alkaline component, volatile acid component, and alcohol component contained in the waste liquid are ammonia, formic acid, and methanol, respectively, and the case where the waste liquid as a whole exhibits alkalinity will be described as an example. However, the alkali component, volatile acid component, and alcohol component contained in the waste liquid are not limited thereto. Further, a case will be described in which sulfuric acid is employed as the acid mixed in the PH adjusting device 10 and an aqueous sodium hydroxide solution is employed as the alkaline liquid sprayed from the alkaline liquid supply device 60 of the first condenser 40.

  First, waste liquid containing ammonia, formic acid, and methanol is supplied from a waste liquid tank (not shown) to the storage tank 11 of the PH adjusting device 10. Then, sulfuric acid is supplied from the acid supply device 12 to the storage tank 11, and the ammonia contained in the waste liquid stored in the storage tank 11 is neutralized to generate ammonia sulfate (neutralized salt). At this time, from the viewpoint of reliably recovering ammonia contained in the waste liquid as ammonia sulfate, the amount of sulfuric acid supplied is adjusted so that the pH of the waste liquid after PH adjustment is 4 to 5. The waste liquid mixed with sulfuric acid is guided to the bottom of the evaporator 21 of the evaporator 20 through the waste liquid supply line 13.

  The waste liquid stored in the bottom of the evaporator 21 is supplied to the waste liquid spray nozzle 26 through the waste liquid circulation pipe 27 by the action of the circulation pump 27a. The waste liquid supplied to the waste liquid spray nozzle 26 is sprayed to the outer surface of each heat transfer tube 29 in the indirect heater 23 by the waste liquid spray nozzle 26 and transmitted through the heating steam supply pipe 19 and the first header 30. Heat is exchanged with the steam supplied to the heat pipe 29 and passing through the inside thereof. By this heat exchange, part of the water in the waste liquid evaporates and steam is generated. At this time, formic acid and methanol contained in the waste liquid are also vaporized together with the evaporation of water. The steam containing formic acid and methanol (steam containing a volatile acid component and an alcohol component) generated in this way is guided to the first condensing device 40 through a steam transfer line 24 connected to the upper portion of the evaporator 21. It will be.

  On the other hand, the waste liquid that has not evaporated on the outer surfaces of the plurality of heat transfer tubes 29 flows down along the outer surface of the heat transfer tubes 29, returns to the waste solution stored at the bottom of the evaporator 21, and again returns to the waste liquid circulation line 27. And is supplied to the waste liquid spray nozzle 26. The waste liquid stored at the bottom of the evaporator 21 is circulated through the waste liquid circulation line 27 until the evaporation concentration process is completed. The waste liquid stored in the evaporator 21 contains ammonia sulfate and sulfuric acid in addition to formic acid and methanol that are vaporized by the heating action of the heat transfer tube 29. Ammonia sulfate and sulfuric acid are heated by the heating action of the heat transfer tube 29. Since it does not evaporate, it remains in the evaporator 21 and is discharged to the outside as a concentrate through the concentrate discharge pipe 28 when the evaporation concentration process of the evaporator 20 is completed. That is, ammonia (alkali component) contained in the waste liquid can be reliably removed from the waste liquid as ammonia sulfate (neutralized salt).

  The steam supplied into the heat transfer pipe 29 via the heating steam supply pipe 19 is cooled by heat exchange with the waste liquid sprayed on the outer surface of the heat transfer pipe 29 to become condensed water, and the indirect heater 23 It accumulates at the bottom of the second header 31. The condensed water is guided to the condensed water discharge pipe 72 through the condensed water drain pipe 25. Further, the steam that has not been converted into condensed water is guided to the second condensing device 70 via the heating steam discharge pipe 32.

  The steam containing formic acid and methanol discharged from the evaporator 20 and guided to the first condenser 40 via the steam transfer pipe 24 is guided to the steam introduction chamber 51 a of the first header 51. Then, as shown by arrow A, after being led to the first storage chamber 52a via the first heat transfer tube 501, it is folded upward in the first storage chamber 52a and shown by arrow B. It is led to the second storage chamber 51b through the second heat transfer tube 502. The steam passing through the heat transfer tube 50 passes through the second heat transfer tube 502 from the first heat transfer tube 501 through the first storage chamber 52a by heat exchange with cooling water that cools the outer surface of the heat transfer tube 50. Therefore, the temperature in the first heat transfer tube 501 is higher than the temperature in the heat transfer tube 502.

  The steam containing formic acid and methanol passing through the inside of the first heat transfer pipe 501 is exchanged with the cooling water sprayed from the cooling water spray nozzle 48 to the outer surface of the first heat transfer pipe 501, and thereby the inside of the first heat transfer pipe 501. Converted into condensed water. Formic acid contained in the steam passing through the first heat transfer tube 501 has a high solubility in water and dissolves in the condensed water generated in the first heat transfer tube 501, so condensed water generated in the first heat transfer tube 501 Becomes formic acid-containing condensed water containing formic acid (acid-containing condensed water). As described above, formic acid contained in the steam passing through the first heat transfer tube 501 is dissolved in the condensed water generated in the first heat transfer tube 501, and is folded back upward in the first storage chamber 52a to form the second heat transfer tube 501. The steam led to the heat pipe 502 becomes the remaining methanol-containing steam (alcohol-containing steam) that does not contain formic acid.

  On the other hand, the methanol-containing steam (alcohol-containing steam) that passes through the second heat transfer pipe 502 is exchanged with the cooling water sprayed from the cooling water spray nozzle 48 to the outer surface of the second heat transfer pipe 502, thereby causing the second heat transfer pipe. In 502, it is converted into methanol-containing condensed water containing methanol (alcohol-containing condensed water). In addition, since the liquefaction temperature of methanol which is an alcohol component is low, it does not condense in the 1st heat exchanger tube 501 with high temperature, but condenses in the 2nd heat exchanger tube 502 with low temperature.

  The formic acid-containing condensed water (acid-containing condensed water) generated in the first heat transfer pipe 501 is pushed by the flow of steam passing through the first heat transfer pipe 501 and guided to the second header 52, and the first storage chamber It will accumulate in 52a. Further, the methanol-containing condensed water (alcohol-containing condensed water) generated in the second heat transfer tube 502 is pushed by the flow of steam passing through the second heat transfer tube 502 and accumulates in the second storage chamber 51b. Become.

  Moreover, since the sodium hydroxide aqueous solution for neutralizing the formic acid containing condensed water produced | generated by the 1st heat exchanger tube 501 is supplied from the alkaline liquid supply apparatus 60, it was produced | generated in the 1st heat exchanger tube 501. The formic acid-containing condensed water becomes condensed water containing sodium formate (neutralized salt) by a neutralization reaction with the aqueous sodium hydroxide solution supplied from the alkaline liquid supply device 60. That is, the condensed water collected in the first storage chamber 52a is condensed water containing sodium formate (neutralized salt). Here, from the viewpoint of reliably recovering formic acid contained in the vapor supplied from the evaporation device 20 as sodium formate, the alkaline liquid supply device 60 is opened and closed so that the measured value by the PH monitor 65 becomes 10 to 11, for example. It is preferable to control the amount of sodium hydroxide aqueous solution to be dispersed by adjusting the opening of the valve 66.

  Condensed water generated in the first heat transfer pipe 501 and stored in the first storage chamber 52 a is guided to the storage can 41 via the condensed water reflux pipe 45. The condensed water guided to the storage can 41 is mixed with the cooling water stored in the storage can 41, and the cooling water is used for heat exchange with the steam passing through the first heat transfer tube 501 and the second heat transfer tube 502. The spray nozzle 48 sprays the first heat transfer tube 501 and the second heat transfer tube 502 on the outer surface.

  The cooling water sprayed on the outer surfaces of the first heat transfer tube 501 and the second heat transfer tube 502 exchanges heat with the steam passing through the insides of the first heat transfer tube 501 and the second heat transfer tube 502, and the first It is converted into steam on the outer surfaces of the heat transfer tube 501 and the second heat transfer tube 502. The steam generated on the outer surfaces of the first heat transfer pipe 501 and the second heat transfer pipe 502 is discharged through the steam reuse pipe 44, and a part thereof is led to the evaporator 20 as a heating source of the evaporator 20. . The remaining steam is led to the second condensing device 70 through the condensing steam pipe 67 and converted into condensed water.

  The cooling water stored in the storage can 41 includes the condensed water introduced by the condensed water reflux line 45, and therefore includes sodium formate and sodium hydroxide that is an alkali for neutralization. Since sodium formate and sodium hydroxide are not vaporized by heat exchange with the steam passing through the plurality of heat transfer pipes 50, they collect at the bottom of the storage can 41, and when the waste liquid treatment is completed, the cooling water discharge pipe 54 is provided as a concentrated liquid. It is discharged to the outside. That is, formic acid (volatile acid component) contained in the waste liquid can be reliably removed from the waste liquid as sodium formate (neutralized salt).

  The methanol-containing condensed water (alcohol-containing condensed water) stored in the second storage chamber 51 b of the first condensing device 40 is guided to the alcohol separating device 80 via the alcohol-containing condensed water supply conduit 46. The methanol-containing condensed water guided to the alcohol separator 80 is sprayed from the condensed water sprayer 81, whereby the methanol component contained in the methanol-containing condensed water is vaporized and separated and removed from the condensed water. Since the aeration tower 82 is decompressed by the decompression means 85, the methanol component can be efficiently separated from the condensed water sprayed in the aeration tower 82. The condensed water from which the methanol component has been separated and removed is accumulated in the aeration tower 82 and supplied to the storage can 41 of the first condensing device 40 as cooling water through the separated water supply pipe 84. On the other hand, the methanol component separated from the condensed water is guided to the alcohol absorption device 90 via the alcohol transfer pipe 83 and the alcohol-containing steam supply pipe 47.

  In addition, the methanol-containing steam that has not been converted to condensed water in the second heat transfer pipe 502 is guided to the alcohol absorption device 90 via the alcohol-containing steam supply pipe 47 connected to the second storage chamber 51b.

  Methanol-containing steam led from the first condensing device 40 to the alcohol absorption device 90 via the alcohol-containing steam supply line 47, and an alcohol separation device 80 via the alcohol transfer line 83 and the alcohol-containing steam supply line 47. The methanol component led to the alcohol absorbing device 90 is guided into the washing tower 92 of the alcohol absorbing device 90 and comes into contact with the dissolving liquid stored in the washing tower 92 and sprayed through the dissolving liquid spraying device 93. Thus, it is dissolved and recovered in the dissolving solution. The alcohol concentration in the dissolving liquid gradually increases with the progress of the waste liquid treatment.

  Next, the steam led from the second header 31 of the indirect heater 23 of the evaporator 20 to the second condenser 70 via the heating steam discharge pipe 32, and the storage can 41 of the first condenser 40 The steam led from the upper part to the second condensing device 70 through the steam reuse conduit 44 and the condensing steam conduit 67 is heated with the cooling water passing through the cooling water supply conduit 71 in the second condensing device 70. It is converted into condensed water by exchange, and is discharged to the outside through the condensed water discharge pipe 72. A part of the condensed water passing through the condensed water discharge pipe 72 was led to the bottom of the storage can 41 of the first condensing device 40 via a makeup water pipe 73 provided in the middle of the condensed water discharge pipe 72. Then, it is sprayed from the cooling water spray nozzle 48 to the heat transfer tube 50 and converted into steam by the heat exchange action of the heat transfer tube 50. The amount of condensed water led to the bottom of the storage can 41 of the first condensing device 40 via the makeup water pipe 73 is provided, for example, by providing a level sensor inside the storage can 41 of the first condensing device 40. It is preferable to adjust so that the amount of the cooling water stored in the storage can 41 is constant based on the detected value from.

  Thus, according to the waste liquid treatment apparatus 1 according to the present embodiment, the alkali component in the waste liquid is reliably removed as a concentrated solution of the neutralized salt in the evaporation apparatus 20, and the volatile acid component generated in the evaporation apparatus 20 and The steam containing the alcohol component is condensed by the first condensing device 40, and the acid-containing condensed water mainly containing the volatile acid component and the alcohol-containing condensed water mainly containing the alcohol component can be recovered separately. Then, in the alcohol separator 80, the alcohol component is separated from the alcohol-containing condensed water generated by the first condenser device 40, and then the condensed water after the alcohol component separation is refluxed to the storage can 41 of the first condenser device 40. Therefore, the condensed water from which the alcohol component is separated can be effectively used as cooling water for heat exchange with the steam passing through the heat transfer tube 50. The condensed water supplied from the alcohol separator 80 to the storage can 41 corresponds to the water in the waste liquid that is evaporated by the evaporator 20, so that it is possible to efficiently use the water resources to perform the waste liquid treatment. become.

  Moreover, since the volatile acid component and the alcohol component are not included in the steam generated on the outer surface of the heat transfer tube 50 of the first condensing device 40, it is volatile in the condensed water generated in the second condensing device 70. The acid component and the alcohol component do not migrate, and the condensed water can be effectively reused or drained to the outside as it is.

  Moreover, in this embodiment, the condensed water produced | generated by the 1st heat exchanger tube 501 of the 1st condensation apparatus 40 can be recirculated to the storage can 41, and can be spread | dispersed on the outer surface of the several heat exchanger tube 50 with the cooling water spraying apparatus 42. Therefore, the condensed water generated in the first heat transfer tube 501 of the first condenser 40 is used as the cooling water used for heat exchange with the steam passing through the inside of the heat transfer tube 50. Can do. Since the condensed water generated in the first heat transfer tube 501 of the first condensing device 40 corresponds to the water in the waste liquid evaporated by the evaporation device 20, the water contained in the waste liquid is circulated through the heat transfer tube 50. Therefore, it can be effectively used as a refrigerant for heat exchange with the steam to be used, and waste liquid treatment can be performed by efficiently utilizing water resources.

  In this embodiment, since the alcohol absorption device 90 is provided, the alcohol component separated by the alcohol separation device 80 and the alcohol component contained in the steam guided through the alcohol-containing steam pipe 47 are dissolved. It can be reliably dissolved and recovered in the working solution. Furthermore, since the alcohol concentration of the dissolving liquid in the alcohol absorption device 90 gradually increases as the waste liquid treatment progresses, an alcohol liquid having a desired alcohol concentration can be easily generated, recovered, and reused. Is possible.

  Furthermore, since the first condensing device 40 includes a steam reuse pipe 44 that connects the upper portion of the storage can 41 and the ejector 15, at least a part of the steam generated in the first condensing device 40 is evaporated. 20 can be used as a heat source for generating steam containing a volatile acid component and an alcohol component. As a result, the waste liquid can be efficiently processed with improved energy efficiency. Moreover, since the vapor | steam produced | generated in the 1st condensing apparatus 40 is a thing in which the water contained in a waste liquid changed state, it can utilize effectively the water contained in the said waste liquid as a heat medium of the evaporator 20. Become.

  Further, in the present embodiment, at least a part of the condensed water generated in the second condensing device 70 is returned to the bottom of the storage can 41 of the first condensing device 40 via the makeup water pipe 73, and the condensed water Is vaporized in the first condenser 40. As described above, at least a part of the generated steam is guided to the evaporation apparatus 20 via the steam reuse pipe 44, and generates steam including a volatile acid component and an alcohol component. Since it is used as a heating source, the condensed water generated in the second condensing device 70 can be effectively used as a heat medium for the evaporator 20.

  In the present embodiment, the waste liquid containing an alkali component, a volatile acid component, and an alcohol component stored in a waste liquid tank (not shown) is temporarily stored in the storage tank 11 of the PH adjustment apparatus 10 before being led to the evaporation apparatus 20. In addition, since the neutralizing acid is mixed with the waste liquid, a neutralized salt of the alkali component and the neutralizing acid in the waste liquid that is removed as the concentrated liquid in the evaporator 20 is generated efficiently and reliably. can do.

  Further, in the present embodiment, the pH of the cooling water stored in the storage can 41 of the first condensing device 40 is measured by the PH monitor 65 installed in the cooling water circulation pipe 57, and the alkaline liquid is based on the measured value. Since it is comprised so that the quantity of the alkali liquid for neutralization sprayed from the supply apparatus 60 can be controlled, all the volatile acid components contained in the cooling water stored by the storage can 41 are removed as neutralization salt. It is possible to reliably spray the amount of alkaline liquid that can be obtained.

  As mentioned above, although one Embodiment of this invention was described, the specific aspect of this invention is not limited to the said embodiment. For example, as shown in FIG. 2, partition members 53a and 53b are provided in the first header 51 and the second header 52, respectively, and the steam introduction chamber 51a, the first storage chamber 52a, the second storage chamber 51b, and the second header A configuration including three storage chambers 52b may be adopted, and condensed water containing alcohol stored in the second storage chamber 51b and the third storage chamber 52b may be guided to the alcohol separation device 80.

  Further, in the present embodiment, an aeration apparatus is adopted as the alcohol separation device 80, but it is not particularly limited to such a configuration. For example, the alcohol-containing condensation guided through the alcohol-containing condensed water supply pipe 46 It is also possible to adopt a configuration in which water is stored in a tank, the tank is heated to vaporize an alcohol component contained in the alcohol-containing condensed water, and the alcohol component is separated from the alcohol-containing condensed water.

  Further, in the alcohol absorption device 90, the alcohol introduced into the water washing tower 87 from the first condensing device 40 and the alcohol separation device 80 by spraying the dissolving liquid stored in the water washing tower 87 from the dissolving liquid spraying device 88. Although it is comprised so that a component can be absorbed, it is not specifically limited to such a structure, For example, the alcohol-containing vapor | steam supply conduit 47 is connected to the bottom part of the water-washing tower 87, and the 1st condensation apparatus 40 and alcohol separation are connected. You may comprise so that the alcohol component supplied from the apparatus 80 may melt | dissolve in the solution for dissolution, passing through the solution for dissolution stored in the water-washing tower 87.

  Further, in the present embodiment, the condensed water stored in the first storage chamber 52a of the first condensing device 40 is configured to be guided to the storage can 41 through the condensed water recirculation conduit 45. For example, a configuration in which condensed water stored in the first storage chamber 52a is drained to the outside as it is may be adopted.

  Moreover, in this embodiment, in order to neutralize the acid containing condensed water produced | generated in the 1st heat exchanger tube 501, the alkali liquid supply apparatus 60 is provided and an alkali fluid is sprayed toward the 1st heat exchanger tube 501. However, the present invention is not particularly limited to such a configuration. For example, a configuration in which an alkali solution for neutralization is injected into the acid-containing condensed water stored in the first storage chamber 52a is employed. You can also. Furthermore, a configuration in which an alkaline solution is injected into the storage can 41 can be employed.

  Further, in the present embodiment, the PH adjusting device 10 includes the storage tank 11 and adopts a configuration in which the storage tank 11 is mixed with a neutralizing acid, but the storage tank 11 is omitted and the evaporation device 20 is omitted. A configuration in which the neutralizing acid is directly mixed in the evaporator 21 may be adopted.

  In the present embodiment, the PH monitor 65 that measures the PH of the cooling water stored in the storage can 41 of the first condensing device 40 is configured to be installed in the cooling water circulation line 49. For example, a configuration in which the PH monitor 65 is installed in the storage can 41 of the first condensing device 40 may be employed.

It is a schematic block diagram which shows the waste liquid processing apparatus which concerns on this invention. It is a schematic block diagram which shows the modification of the waste liquid processing apparatus shown in FIG. It is a schematic block diagram which shows the conventional waste water treatment equipment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Waste liquid processing apparatus 20 Evaporating apparatus 40 Condensing apparatus 50 Heat transfer pipe 501 1st heat transfer pipe 502 2nd heat transfer pipe 51 1st header 51a Steam introduction chamber 51b 2nd storage chamber 52 2nd header 52a 1st storage chamber 80 Alcohol separation apparatus

Claims (5)

A waste liquid treatment apparatus for treating a waste liquid containing an alkali component, a volatile acid component and an alcohol component,
An evaporation device that mixes an acid that neutralizes the alkali component and heats and evaporates the waste liquid, thereby leaving a neutralized salt, and generating and discharging a vapor containing a volatile acid component and an alcohol component;
A condensing device for condensing steam discharged from the evaporation device to separately produce acid-containing condensed water mainly containing a volatile acid component and alcohol-containing condensed water mainly containing an alcohol component;
An alcohol separation device for separating an alcohol component from the alcohol-containing condensed water produced by the condensation device,
The condensing device includes a steam introducing chamber into which steam discharged from the evaporator is introduced,
The steam introduced into the steam introduction chamber is introduced through the first heat transfer tube, and the first storage chamber for storing the condensed water generated in the first heat transfer tube;
The steam introduced into the first storage chamber is introduced through the second heat transfer tube, and the second storage chamber stores the condensed water generated in the second heat transfer tube,
The steam passing through the first heat transfer tube is volatilized from the acid-containing condensed water in which the volatile acid component contained in the steam is dissolved by the heat exchange with the cooling water that cools the outer surface of the first heat transfer tube. Converted into residual alcohol-containing steam from which the acidic acid component has been removed,
The alcohol-containing steam passing through the second heat transfer tube is converted into alcohol-containing condensed water by heat exchange with cooling water that cools the outer surface of the second heat transfer tube,
The alcohol separator is a waste liquid treatment apparatus configured to guide condensed water from which an alcohol component has been separated to the condenser as the cooling water.   The waste liquid treatment apparatus according to claim 1, wherein the alcohol separation device is an aeration device that vaporizes alcohol components from the condensed water by spraying the alcohol-containing condensed water under reduced pressure.   The waste liquid treatment apparatus according to claim 1, further comprising an alcohol absorption device that contacts and dissolves the alcohol component separated by the alcohol separation device. The condensing device includes a storage can that stores cooling water;
A spraying device for spraying cooling water stored in the storage can on the outer surfaces of the first heat transfer tube and the second heat transfer tube;
By exchanging heat between the steam passing through the first heat transfer tube and the second heat transfer tube and the cooling water sprayed on the outer surfaces of the first heat transfer tube and the second heat transfer tube, the first heat transfer tube and the At least a part of the steam generated by evaporating the cooling water on the outer surface of the second heat transfer tube is used as a heating source for generating steam containing a volatile acid component and an alcohol component in the evaporator. The waste liquid treatment apparatus according to any one of claims 1 to 3, wherein the waste liquid treatment apparatus is configured to be supplied. The condensing device includes an alkaline liquid supply device that supplies an alkaline liquid for neutralization to the acid-containing condensed water generated in the first heat transfer tube;
Condensed water, which is generated by a neutralization reaction of the alkaline liquid and acid-containing condensed water supplied from the alkaline liquid supply device and contains neutralized salt stored in the first storage chamber, is guided to the storage can as the cooling water. The waste liquid treatment apparatus according to claim 4, further comprising a reflux unit.

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