Electrolytic bath washing wastewater recovery system
By designing the electrolytic tank washing tank wastewater recycling system, the problems of alkaline liquid deterioration and sodium salt waste in the electrolytic tank washing tank wastewater treatment are solved, and the recycling and reuse of the anode and cathode washing tank wastewater is realized, thereby reducing alkaline losses and sewage treatment load.
Patent Information
- Application Number
- CN202420456594.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-08
- Publication Date
- 2025-03-11
- Estimated Expiration
- 2034-03-08
AI Technical Summary
During the wastewater treatment of the existing electrolytic tank washing tank, the amount of wastewater in the cathode chamber is large but the amount of alkali liquid is small, resulting in deterioration of alkali liquid and waste of sodium salt; at the same time, the wastewater generated by the second wash tank is directly discharged, increasing the sewage treatment load and causing waste of sodium salt.
An electrolytic tank washing tank wastewater recycling system is designed, and the wastewater recycling and reuse of the anode and cathode washing tank wastewater is realized by connecting the electrolytic tank, anode liquid drain tank, a light salt water dechlorination device, a salt water tank, a cathode liquid drain tank and an accident chlorine system.
This system can not only recover salt and alkali in the anode wash tank wastewater, reduce alkali loss in the caustic soda production process, but also reduce the amount of water replenishment and sewage discharge and treatment of salt water.
Smart Images
Figure CN222594033U_ABST
Abstract
Description
Technical field:
[0001] The utility model relates to the field of chlor-alkali, and in particular to an electrolytic tank washing wastewater recovery system. Background technology:
[0002] Before stopping the electrolytic cell, it is necessary to wash the tank and drain the liquid to avoid NaCl and NaOH crystals in the anode and cathode clogging the liquid inlet pipe, thereby affecting the electrolyte flow when it is started again. After the electrolytic cell is stopped, in order to ensure that the electrolytic cell is thoroughly cleaned after the electrolytic cell is stopped, it is necessary to drain the liquid twice in a row. During the first washing process, due to the residual electrolyte in the electrolytic cell, the tank washing wastewater contains more NaOH and NaCl. The anode is discharged to the anode liquid discharge tank, and after dechlorination treatment, it is used as brine for production, while the cathode (about 15% NaOH) is discharged to the cathode liquid discharge tank and sent to the accident chlorine system as the accident chlorine system alkali liquid, so as to recover the NaOH and NaCl in the tank washing wastewater; during the second washing process, due to the low salt content of the wastewater, in order to speed up the cleaning and drainage speed, the tank washing wastewater will be directly discharged to the sewage treatment system. Such treatment has the following problems:
[0003] 1. The amount of wastewater sent from the cathode chamber to the accident chlorine system is large, and the amount of alkali solution used in the accident chlorine system is small. Long-term storage here will cause the alkali solution to deteriorate, that is, react with CO2 in the air, and this part of the alkali solution cannot directly participate in production, resulting in a waste of sodium salt;
[0004] 2. Although the wastewater generated in the second tank washing process has a low salt content, directly treating it through the sewage treatment system will not only increase the sewage treatment load, but also cause a waste of sodium salt. Utility model content:
[0005] The utility model aims to provide an electrolytic tank washing wastewater recovery system.
[0006] The utility model is implemented by the following technical solutions:
[0007] An electrolytic tank washing tank wastewater recovery system comprises an electrolytic tank, wherein the liquid inlet of the electrolytic tank is connected to the liquid discharge port of a washing water tank, the anode liquid discharge port of the electrolytic tank is connected to the liquid inlet of an anode liquid discharge tank, the liquid discharge port of the anode liquid discharge tank is connected to the liquid inlet of a dechlorinated salt water dechlorination device, the liquid discharge port of the dechlorinated salt water dechlorination device is connected to the liquid inlet of a salt treating tank, the liquid discharge port of the salt treating tank is connected to the liquid inlet of anode liquid treating tank, and the liquid discharge port of the salt treating tank is connected to the liquid inlet of anode liquid treating tank of the electrolytic tank; the cathode liquid discharge port of the electrolytic cell is connected to the liquid inlet of cathode liquid discharge tank, and the liquid discharge port of cathode liquid discharge tank is respectively connected to the alkali liquid inlet of an accident chlorine system and the liquid inlet of the salt treating tank.
[0008] Preferably, the discharge port of the salt-refining tank is connected to the liquid inlet of the crude brine refining device, the discharge port of the crude brine refining device is connected to the liquid inlet of the crude brine filtering device, the discharge port of the crude brine filtering device is connected to the liquid inlet of the chelating resin adsorption device, and the discharge port of the chelating resin adsorption device is connected to the liquid inlet of the electrolytic cell.
[0009] Preferably, an accidental chlorine-alkali liquid recovery valve and a cathode washing tank wastewater recovery valve are provided between the cathode liquid drain tank and the accidental chlorine system and the brine tank.
[0010] Advantages of the utility model: The utility model can not only recover salt and alkali in the anode washing tank wastewater, but also recover the alkali solution contained in the cathode washing tank wastewater of the electrolytic cell, which can reduce the alkali loss in the caustic soda production process, reduce the brine replenishment and sewage discharge and treatment volume. Description of the drawings:
[0011] Figure 1 It is a structural schematic diagram of the utility model.
[0012] In the figure: electrolytic cell 1, cleaning water tank 2, anolyte discharge tank 3, brine dechlorination device 4, salt water tank 5, salt tank 6, cathode liquid discharge tank 7, emergency chlorine system 8, crude brine refining device 9, crude brine filtering device 10, chelating resin adsorption device 11. Specific implementation method:
[0013] like Figure 1 As shown, an electrolytic tank washing tank wastewater recovery system includes an electrolytic tank 1, the liquid inlet of the electrolytic tank 1 is connected to the liquid discharge port of the cleaning tank 2, the anode liquid discharge port of the electrolytic tank 1 is connected to the liquid inlet of the anode liquid discharge tank 3, the liquid discharge port of the anode liquid discharge tank 3 is connected to the liquid inlet of the dechlorination device of the light salt water 4, the liquid discharge port of the dechlorination device of the light salt water 4 is connected to the liquid inlet of the salt water tank 5, the liquid discharge port of the salt water tank 5 is connected to the liquid inlet of the salt water tank 6, and the liquid discharge port of the salt water tank 6 is connected to the crude brine refining device 9, the discharge port of the crude brine refining device 9 is connected with the liquid inlet of the crude brine filtering device 10, the discharge port of the crude brine filtering device 10 is connected with the liquid inlet of the chelating resin adsorption device 11, and the discharge port of the chelating resin adsorption device 11 is connected with the anode liquid inlet of the electrolytic cell 1; the cathode discharge port of the electrolytic cell 1 is connected with the liquid inlet of the cathode liquid discharge tank 7, and the discharge port of the cathode liquid discharge tank 7 is respectively connected with the alkali liquid import of the accident chlorine system 8 and the liquid inlet of the brine tank 5;
[0014] When the electrolytic cell 1 is cleaned, the cleaning water in the cleaning water tank 2 is injected into the electrolytic cell 1 for flushing, the tank washing wastewater of the anode of the electrolytic cell 1 is injected into the anode liquid discharge tank 3 for storage, and then sent to the light salt water dechlorination device 4 for dechlorination, and the dechlorinated wastewater is sent to the salt water tank 5 for standby; and the tank washing wastewater of the cathode of the electrolytic cell 1 is injected into the cathode liquid discharge tank for storage, and then sent to the accident chlorine system 8 as alkali solution as needed, or sent to the salt water tank 5 for standby; in the salt water tank 5, the anode wastewater and the cathode wastewater after dechlorination are mixed with the water injected into the salt water tank 5 to obtain brine, and then refined and filtered by the crude brine refining device 9 and the crude brine filtering device 10, and then sent to the chelating resin adsorption device 11 to remove calcium and magnesium ions, and finally sent to the electrolytic cell 1 for electrolysis;
[0015] This process can not only recover the salt and alkali in the anode washing tank wastewater, but also recover the alkali solution contained in the cathode washing tank wastewater of electrolytic cell 1, which can reduce the alkali loss in the caustic soda production process, reduce the brine replenishment and sewage discharge and treatment volume.
[0016] An accidental chlor-alkali liquid recovery valve and a cathode washing tank wastewater recovery valve are provided between the cathode liquid drain tank 7, the accidental chlorine system 8 and the chemical salt water tank 5. When the cathode washing tank wastewater needs to be sent to the accidental chlorine system 8, the accidental chlor-alkali liquid recovery valve is opened and the cathode washing tank wastewater recovery valve is closed; when the cathode washing tank wastewater needs to be sent to the chemical salt water tank 5, the accidental chlor-alkali liquid recovery valve is closed and the cathode washing tank wastewater recovery valve is opened.
[0017] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. An electrolytic tank washing wastewater recovery system, characterized in that: The invention comprises an electrolytic cell, wherein the liquid inlet of the electrolytic cell is connected to the liquid discharge port of the cleaning water tank, the anode liquid discharge port of the electrolytic cell is connected to the liquid inlet of the anode liquid discharge tank, the liquid discharge port of the anode liquid discharge tank is connected to the liquid inlet of a dechlorinated salt water device, the liquid discharge port of the dechlorinated salt water device is connected to the liquid inlet of a salt treating tank, the liquid discharge port of the salt treating tank is connected to the liquid inlet of the salt treating tank, and the liquid discharge port of the salt treating tank is connected to the anode liquid inlet of the electrolytic cell; the cathode liquid discharge port of the electrolytic cell is connected to the liquid inlet of the cathode liquid discharge tank, and the liquid discharge port of the cathode liquid discharge tank is respectively connected to the alkali liquid inlet of the accident chlorine system and the liquid inlet of the salt treating tank.
2. The electrolytic tank washing wastewater recovery system according to claim 1, characterized in that: The discharge port of the salt-refining tank is connected to the liquid inlet of the crude brine refining device, the discharge port of the crude brine refining device is connected to the liquid inlet of the crude brine filtering device, the discharge port of the crude brine filtering device is connected to the liquid inlet of the chelating resin adsorption device, and the discharge port of the chelating resin adsorption device is connected to the liquid inlet of the electrolytic cell.
3. The electrolytic tank washing wastewater recovery system according to claim 2, characterized in that: An accidental chlorine-alkali liquid recovery valve and a cathode washing tank wastewater recovery valve are provided between the cathode liquid drainage tank, the accidental chlorine system and the salt water tank.