CN204714912U - A kind of device rinsing electrolyzer - Google Patents

Abstract

The utility model relates to the technical field of flushing an electrolytic cell for electrolyzing seawater or seawater desalination of concentrated seawater, and discloses a device for flushing an electrolytic cell. flushing the electrolytic cell; and a control device for controlling the low-pressure flushing water pump to flush the electrolytic cell. The utility model uses a low-pressure flushing water pump to carry out low-pressure flushing of the electrolytic cell to replace the electrolyte in the electrolytic cell with seawater and form a turbulent flow in the electrolytic cell so that the scaling during the electrolysis process falls off from the surface of the pole plate, thereby reducing the Plate fouling risk, and can effectively extend the pickling cycle of the plate.

Description

A device for flushing an electrolyzer

technical field

The utility model relates to a technique for flushing an electrolytic cell for electrolyzing seawater or desalinating concentrated seawater, in particular to a device for flushing an electrolytic cell.

Background technique

With the economic development of coastal provinces, especially with the advancement of the "One Belt, One Road" national strategy, coastal areas have begun to build and expand coastal power plants on a large scale to meet the growing demand for electricity. At present, coastal power plants have begun to use seawater or seawater desalination. Seawater is electrolyzed to produce sodium hypochlorite, which is used as a bactericide and algicide for the circulating water of the generating set.

The main components of seawater and seawater desalination concentrated seawater are Cl-, Na+, Mg2+, K+, SO42-, etc. Directly electrolyzing seawater or seawater desalination concentrated seawater to produce chlorine is to use special electrodes to directly conduct seawater or seawater desalination concentrated seawater. In electrolysis, the chlorine gas produced by the anode reacts with the OH- produced by the cathode to form hypochlorite. Meanwhile, some side reactions occur due to the anodic oxidation and cathodic reduction of ClO- and the influence of other ions, and these side reactions reduce the current efficiency. Its main reaction equation is:

Main response:

Anode: 2Cl ^- →Cl ₂ +2e

Cathode: 2H ₂ O+2e→H ₂ +2OH ^-

Solution: Cl ₂ +H ₂ O→HClO+Cl ^- +H ⁺

HClO→H ⁺ +ClO ^-

side effects:

Anode: 12ClO ^- +6H ₂ O→4ClO ₃ ^- +8Cl ^- +12H ⁺ +3O ₂ +12e

2H ₂ O→O ₂ +4H ⁺ +4e

Cathode: ClO ^- + _H2O +2e→Cl ^- +2OH ^-

Solution: 2HClO+ClO ^- → ClO ₃ ^- +2Cl ^- +2H ⁺

H ₂ +ClO ^- →H ₂ O+Cl ^-

Other reactions:

Mg ²⁺ +2OH ^- → Mg(OH) ₂

Ca ²⁺ +2OH ^- → Ca(OH) ₂

HClO, ClO ^- , and Cl ₂ generated in the above reactions are all called available chlorine.

It can be seen from the principle of electrolysis that when seawater or desalinated concentrated seawater is electrolyzed, in addition to producing sodium hypochlorite and hydrogen, calcium and magnesium deposits will inevitably be produced, and these deposits will be on the cathode plate of the electrolytic cell. As a result, the voltage of the electrolytic cell increases, the current efficiency decreases, and the power consumption increases. Therefore, it is necessary to pickle the electrolytic cell regularly to remove the deposits on the surface of the cathode. It can be known from theoretical deduction that, without considering the influence of other ions, when the pH>9.3, Mg(OH) ₂ precipitation will occur, and when the pH>12.3, Ca(OH) ₂ will precipitate. Therefore, in the cathodic electrolysis process, if Mg(OH) ₂ and CaCO ₃ precipitates can occur if the local pH is too high or the flow rate is too low.

Scaling on the plate will lead to increased resistance, reduced electrolytic current, and increased DC power consumption. If it is not treated in time, as the scale continues to accumulate on the surface of the plate, it will cause the anode and cathode plates to overlap due to scale. Short circuit, resulting in high temperature instantaneously, in severe cases, the plate will be broken down and the electrolytic cell shell will be burned out, so controlling plate scaling is essential for the stable operation of the process of electrolyzing seawater or desalinating concentrated seawater to produce sodium hypochlorite, and avoiding short circuit damage to the plate has an important role.

Utility model content

The purpose of the utility model is to provide a device for flushing the electrolytic cell, which is used for flushing the electrolytic cell of electrolyzed seawater or desalinated concentrated seawater to solve the problem of prolonging the pickling cycle of the electrolytic cell.

In order to achieve the above object, the utility model provides a device for flushing the electrolytic cell, which includes: a low-pressure flushing water pump connected to the inlet of the electrolytic cell for flushing the electrolytic cell; and a control device for To control the low-pressure flushing water pump to flush the electrolytic cell.

Preferably, the device further includes: a hardness detection device for detecting the hardness difference between the inlet and outlet of the electrolytic cell; and/or a residual chlorine meter connected to the outlet of the electrolytic cell for detecting the The chlorine content of the liquid at the outlet of the tank; the control device controls the low-pressure flushing water pump to flush the electrolytic cell according to the hardness difference and/or the chlorine content.

Preferably, the hardness detection device includes: a first hardness gauge connected to the inlet of the electrolytic cell for detecting the hardness of the liquid at the inlet of the electrolytic cell; and a second hardness gauge connected to the electrolytic cell The outlet is used to detect the hardness of the liquid at the outlet of the electrolytic cell; wherein, the hardness difference is determined by the control device through the hardness of the liquid at the inlet of the electrolytic cell and the hardness of the liquid at the outlet of the electrolytic cell The hardness difference is calculated.

Preferably, the control device controlling the low-pressure flushing water pump to flush the electrolytic cell according to the hardness difference includes: the control device controls to stop the water passing through the water inlet pump when the hardness difference is greater than a predetermined hardness difference. Water is fed into the electrolytic cell, and the low-pressure flushing water pump is controlled to flush the electrolytic cell.

Preferably, the control device controlling the low-pressure flushing water pump to flush the electrolytic tank according to the chlorine content includes: the control device controls to stop the water passing through the water inlet pump when the chlorine content is less than a predetermined chlorine content. Water is fed into the electrolytic cell, and the low-pressure flushing water pump is controlled to flush the electrolytic cell.

Preferably, the control device controlling the low-pressure flushing water pump to flush the electrolyzer according to the hardness difference and the chlorine content includes: the control device is when the hardness difference is greater than a predetermined hardness difference and the chlorine When the chlorine content is less than the predetermined chlorine content, the control stops the water intake to the electrolytic cell through the water inlet pump, and controls the low-pressure flushing water pump to flush the electrolytic cell.

Through the above technical scheme, the utility model uses a low-pressure flushing water pump to perform low-pressure flushing on the electrolytic cell to replace the electrolyte in the electrolytic cell with seawater and form turbulent flow in the electrolytic cell so that the scaling in the electrolysis process is removed from the plate The surface is peeled off, thereby reducing the risk of fouling of the plate, and can effectively extend the pickling cycle of the plate.

Other features and advantages of the present utility model will be described in detail in the following specific embodiments.

Description of drawings

The accompanying drawings are used to provide a further understanding of the utility model, and constitute a part of the description, together with the following specific embodiments, are used to explain the utility model, but do not constitute a limitation to the utility model. In the attached picture:

Fig. 1 is the block diagram of the device of flushing electrolyzer that the utility model provides;

Fig. 2 is the block diagram of the device for flushing the electrolyzer provided by the specific embodiment of the present invention;

Fig. 3 is the structural representation of the generation device that electrolyzes seawater or seawater desalination thick seawater that the utility model provides to produce sodium hypochlorite; And

Fig. 4 is a flow chart of the method for flushing the electrolyzer provided by the utility model.

Explanation of reference signs

1 Water inlet pump 2 Low pressure flushing water pump

3 Self-cleaning filter 4 Flow meter

5 Thermometer 6 First Hardness Scale

7 PLC controller 8 Remote computer

9 Electrolyzer 10 Pickling water tank

11 Pickling pump 12 Rectifier electric control cabinet

13 Second hardness scale 14 Residual chlorine meter

15 Sodium hypochlorite storage tank 16 Sodium hypochlorite dosing pump

Detailed ways

The specific embodiment of the utility model will be described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described here are only used to illustrate and explain the utility model, and are not intended to limit the utility model.

Fig. 1 is a block diagram of the device for flushing the electrolyzer provided by the utility model, as shown in Fig. 1, the device includes a low-pressure flushing water pump and control equipment. The low-pressure flushing water pump is connected to the inlet of the electrolytic cell for flushing the electrolytic cell, and the control device is used to control the low-pressure flushing water pump to flush the electrolytic cell. That is to say, the low-pressure flushing water pump flushes the electrolytic cell under the control of the control device, and when the control device controls the flushing operation of the low-pressure flushing water pump is another research object of the present invention, and the specific method will be elaborated below. However, in addition to the methods described below, the control device can flush the electrolytic cell when the water inlet pump stops feeding the electrolytic cell, or it can flush the electrolytic cell at regular intervals (at this time, it should also be Stop the water inlet pump to feed water to the electrolyzer).

Fig. 2 is a block diagram of the device for flushing the electrolyzer provided by the specific embodiment of the utility model. As shown in Fig. 2, the device provided by the utility model also includes hardness detection equipment and/or residual chlorine meter, that is to say, it can only include The hardness testing equipment either only includes a residual chlorine meter, or includes both hardness testing equipment and a residual chlorine meter. Wherein, the hardness detection device can be used to detect the hardness difference between the inlet and the outlet of the electrolytic cell, and the residual chlorine meter can be connected to the outlet of the electrolytic cell to detect the chlorine content of the liquid at the outlet of the electrolytic cell. The control device can control the low-pressure flushing water pump to flush the electrolytic cell according to the hardness difference detected by the hardness detection device and/or the chlorine content detected by the residual chlorine meter. Generally speaking, the hardness difference between the inlet and outlet of the electrolytic cell or the chlorine content of the liquid at the outlet of the electrolytic cell can reflect the structural conditions in the electrolytic cell. The difference in hardness or the change in the chlorine content of the liquid at the outlet of the electrolytic cell determines the timing of starting the low-pressure flushing water pump to flush the electrolytic cell.

Specifically, in the case that the control device controls the low-pressure flushing water pump to flush the electrolytic cell according to the hardness difference detected by the hardness detection device, the control device determines that the hardness difference between the inlet and outlet of the electrolytic cell is greater than the predetermined hardness difference. Under the circumstances, the control stops feeding the electrolytic cell through the water inlet pump, and controls the low-pressure flushing water pump to flush the electrolytic cell.

When the control device controls the low-pressure flushing water pump to flush the electrolytic cell according to the chlorine content detected by the residual chlorine meter, the control device stops the flow through the electrolytic cell when the chlorine content of the liquid at the outlet of the electrolytic cell is less than the predetermined chlorine content. The water pump feeds water into the electrolytic cell, and controls the low-pressure flushing water pump to flush the electrolytic cell.

When the control device controls the low-pressure flushing water pump to flush the electrolytic cell according to the hardness difference detected by the hardness detection device and the chlorine content detected by the residual chlorine meter, the hardness difference between the inlet and outlet of the electrolytic cell is controlled by the control device. When the hardness difference is greater than the predetermined value and the chlorine content of the liquid at the outlet of the electrolyzer is less than the predetermined chlorine content, the water inlet pump is controlled to stop feeding the electrolyzer, and the low-pressure flushing water pump is controlled to flush the electrolyzer.

The hardness change before and after seawater electrolysis is monitored through the hardness testing equipment and residual chlorine meter, and the efficiency of electrolysis is monitored, so that the surface structure of the substrate can be judged according to the detected hardness change. The effective efficiency of electrolysis is calculated and analyzed for the effective output and electrolysis efficiency of the device, so as to judge whether the current efficiency is lower than the preset value or the daily operation value. According to the detected situation, it can be analyzed whether there is any abnormality in the substrate, that is, scaling Whether the amount exceeds the normal range, so that the fouling of the plate can be dealt with in time, which effectively improves the reliability of electrolysis.

Through the above analysis, when the device for flushing the electrolytic cell provided by the present invention only includes hardness detection equipment, the control device can control the low-pressure flushing water pump to flush the electrolytic cell only according to the hardness difference detected by the hardness detection device; In the case of including the residual chlorine meter, the control device can control the low-pressure flushing water pump to flush the electrolytic cell only according to the chlorine content detected by the residual chlorine meter; The hardness difference detected by the hardness testing equipment and the chlorine content detected by the residual chlorine meter are used to control the low-pressure flushing water pump to flush the electrolytic cell. The tank is rinsed. Obviously, in the case where the device for flushing the electrolyzer provided by the utility model includes both the hardness detection equipment and the residual chlorine meter, if one of the hardness detection device and the residual chlorine meter breaks down and cannot work normally, the control equipment can be based on The data detected by the other is used to control the flushing of the electrolytic tank by the low-pressure flushing water pump.

As shown in Figure 2, the above-described hardness testing equipment can include a first hardness gauge and a second hardness gauge, the first hardness gauge can be connected to the inlet of the electrolytic cell for detecting the hardness of the liquid at the inlet of the electrolytic cell, and the second hardness gauge can be connected to the inlet of the electrolytic cell. The hardness meter can be connected to the outlet of the electrolytic cell to detect the hardness of the liquid at the outlet of the electrolytic cell, so that the control device can calculate the difference between the hardness of the liquid at the inlet of the electrolytic cell and the hardness of the liquid at the outlet of the electrolytic cell Get hardness difference. Certainly, the utility model is not limited thereto, as long as the equipment that can obtain the hardness difference of the liquid at the entrance and exit of the electrolytic cell is within the scope of protection of the utility model.

Fig. 3 is the structure schematic diagram of the generation device that electrolyzes seawater or seawater desalination thick seawater that the utility model provides to produce sodium hypochlorite, in Fig. 3 dashed line represents signal line, and solid line represents pipeline route. As shown in Figure 3, the water inlet pump 1 and the low-pressure flushing water pump 2 are connected to the inlet of the electrolytic cell 9 through the self-cleaning filter 3, the low-pressure flushing water pump 2 is connected in parallel with the water inlet pump 1, and the self-cleaning filter 3 and the electrolytic cell Flow meter 4, thermometer 5 and first hardness gauge 6 are installed on the pipeline connected by 9, electrolytic tank 9 is connected with pickling box 10 by pickling pump 11, to carry out pickling to electrolytic tank 9, electrolytic tank 9 is also connected with The rectification electric control cabinet 12 is connected, and the external AC power is converted into direct current through the rectification electric control cabinet 12 to supply power to the electrolytic cell 9 for electrolysis, and the electrolysis voltage value and the electrolysis current value can also be displayed on the rectification electric control cabinet 12. 9. A second hardness meter 13 and a residual chlorine meter 14 are installed on the pipeline connected to the sodium hypochlorite storage tank 15. The above flowmeter 4, thermometer 5, first hardness gauge 6, second hardness gauge 13 and residual chlorine meter 14 are all connected to the PLC controller 7, and the PLC controller 7 is bidirectionally connected to the remote computer 8 to jointly realize the operating state of the polar plate The calculation, analysis and evaluation of the calculation, the control equipment of the device for flushing the electrolyzer provided by the utility model can be jointly realized by the PLC controller 7 and the remote computer 8. In addition, the sodium hypochlorite storage tank 15 is connected with the sodium hypochlorite dosing pump 16, so as to add sodium hypochlorite through the sodium hypochlorite dosing pump 16 boxes.

Fig. 4 is a flow chart of the method for flushing the electrolytic cell provided by the utility model. As shown in Fig. 4, the method includes: flushing the electrolytic cell by controlling the low-pressure flushing water pump, specifically including: detecting the entrance of the electrolytic cell The hardness difference with the liquid at the outlet and/or the chlorine content of the liquid at the outlet of the electrolytic cell; according to the hardness difference and/or the chlorine content, the low-pressure flushing water pump is controlled to flush the electrolytic cell.

The preferred embodiment of the utility model has been described in detail above in conjunction with the accompanying drawings, but the utility model is not limited to the specific details of the above-mentioned embodiment. These simple modifications all belong to the protection scope of the present utility model.

In addition, the raw water of the general sodium hypochlorite generating device is raw seawater, but the utility model can use seawater to desalinize the concentrated seawater, which has high salinity and high temperature. The service life of the device is long (especially in winter when the original seawater temperature is low), and seawater desalination and concentrated seawater can be turned from waste to treasure, thereby protecting the marine environment.

In addition, it should be noted that the various specific technical features described in the above specific implementation manners may be combined in any suitable manner if there is no contradiction. In order to avoid unnecessary repetition, the utility model will not further describe various possible combinations.

In addition, any combination of various implementations of the present invention can also be made, as long as they do not violate the idea of the present invention, they should also be regarded as the disclosed content of the present invention.

Claims (6)

1. rinse a device for electrolyzer, it is characterized in that, this device comprises:

Low-pressure washing water pump, is connected to the entrance of described electrolyzer, for rinsing described electrolyzer; And

Operating device, rinses described electrolyzer for controlling described low-pressure washing water pump.

2. device according to claim 1, is characterized in that, this device also comprises:

New Hardness Testing Device, for the difference of hardness of the ingress and exit liquid of detecting electrolyzer; And/or

Chlorine residue instrument, is connected to the outlet of described electrolyzer, for detecting the cl content of the exit liquid of described electrolyzer;

Described operating device controls described low-pressure washing water pump according to described difference of hardness and/or described cl content and rinses described electrolyzer.

3. device according to claim 2, is characterized in that, described New Hardness Testing Device comprises:

First scale of hardness, is connected to the entrance of described electrolyzer, for detecting the hardness of the ingress liquid of described electrolyzer; And

Second scale of hardness, is connected to the outlet of described electrolyzer, for detecting the hardness of the exit liquid of described electrolyzer;

Wherein, described difference of hardness asks mathematic interpolation to obtain by described operating device by the hardness of the hardness of the ingress liquid to described electrolyzer and the liquid of described electrolyzer outlet.

4. the device according to Claims 2 or 3, is characterized in that, described operating device controls described low-pressure washing water pump according to described difference of hardness to carry out flushing to described electrolyzer and comprise:

Described operating device, when described difference of hardness is greater than predetermined hardness difference, is controlled to stop being intake to described electrolyzer by intake pump, and controls described low-pressure washing water pump and rinse described electrolyzer.

5. device according to claim 2, is characterized in that, described operating device controls described low-pressure washing water pump according to described cl content to carry out flushing to described electrolyzer and comprise:

Described operating device, when described cl content is less than predetermined cl content, is controlled to stop being intake to described electrolyzer by intake pump, and controls described low-pressure washing water pump and rinse described electrolyzer.

6. device according to claim 2, is characterized in that, described operating device controls described low-pressure washing water pump according to described difference of hardness and described cl content to carry out flushing to described electrolyzer and comprise:

Described operating device, when described difference of hardness is greater than predetermined hardness difference and described cl content is less than predetermined cl content, is controlled to stop being intake to described electrolyzer by intake pump, and controls low-pressure washing water pump and rinse described electrolyzer.