Chlorate electrolyte concentration control device and method based on electrolyte circulating tank

Abstract

The invention discloses a chlorate electrolyte concentration control device and method based on electrolyte circulating tanks. The chlorate electrolyte concentration control device comprises an electrolytic tank, a plurality of electrolyte circulating tanks arranged in sequence from high to low, a sodium chlorate head tank and an electrolyte middle tank. A sodium chlorate solution from an elevated tank enters a first circulating tank and is fed into an electrolytic tank by a circulating pump for an electrolytic reaction; and the electrolyte flows back to the first circulating tank through the liquid outlet header pipe. And the upper part of each circulating tank is provided with an overflow port, and the electrolyte sequentially overflows to the next-stage circulating tank after the liquid level rises. And each circulating tank is provided with a circulating pump, and the electrolyte is adjusted to a proper temperature through a heat exchanger and then is sent back to the electrolytic tank for continuous electrolysis, so that chlorate is gradually consumed. And the concentration of the electrolyte is gradually reduced through multi-stage circulation and stage-by-stage staying. According to the invention, the concentration of the electrolyte is continuously and stably controlled, and the electrolysis efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of chemical engineering technology, and in particular to a chlorate electrolyte concentration control device and method based on an electrolyte circulation tank. Background Technology

[0002] Currently, in sodium chlorate electrolysis, the concentration of the electrolyte is a crucial factor affecting electrolysis efficiency and the quality of the electrolysis products. Traditional methods for controlling electrolyte concentration typically rely on one-time dilution or overflow discharge. These methods not only struggle to precisely control concentration changes but also tend to lead to low electrolysis efficiency and high energy consumption.

[0003] Therefore, how to improve electrolysis efficiency and reduce energy consumption through precise concentration adjustment has always been a technical challenge in the field of sodium chlorate electrolysis. To address this, this invention proposes a chlorate electrolyte concentration control device and its application method based on an electrolyte circulation tank, aiming to optimize the electrolysis process by precisely adjusting the concentration through a multi-stage electrolyte circulation tank. Summary of the Invention

[0004] To achieve the above objectives, the present invention provides the following technical solution: A chlorate electrolyte concentration control device based on an electrolyte circulation tank includes: an electrolytic cell for converting sodium chlorate solution into sodium perchlorate solution; multiple electrolyte circulation tanks for controlling the sodium chlorate concentration in the electrolyte, the multiple electrolyte circulation tanks being arranged in a gradient from high to low concentration, the main outlet pipe of the electrolytic cell being connected to the first electrolyte circulation tank, each electrolyte circulation tank having an overflow port and being connected to the next circulation tank through an overflow pipe, the electrolyte entering the next circulation tank step by step through the overflow pipe; the bottom outlet of each electrolyte circulation tank being connected to the main inlet pipe of the electrolytic cell through an electrolyte circulation pump, each electrolyte circulation pump to the electrolytic cell having an electrolyte heat exchanger for adjusting the electrolyte temperature to ensure the inlet temperature, the electrolyte in the electrolyte circulation tank returning to the electrolytic cell after passing through the electrolyte heat exchanger.

[0005] Furthermore, the device also includes a sodium chlorate high-level tank, the outlet of which is connected via a pipeline to the first electrolyte circulation tank among a plurality of electrolyte circulation tanks.

[0006] Furthermore, the overflow ports of each electrolyte circulation tank are at the same height and are located on the upper part of the inner wall of the tank.

[0007] Furthermore, the height difference of each electrolyte circulation tank is consistent.

[0008] Furthermore, the last electrolyte circulation tank in the plurality of electrolyte circulation tanks is connected to an intermediate electrolyte tank through an overflow pipe. The intermediate electrolyte tank is used to store the electrolyte that overflows from the last circulation tank and has reached the target concentration, as qualified electrolyte for subsequent processes.

[0009] Furthermore, the number of the plurality of electrolyte circulation tanks is four.

[0010] On the other hand, the present invention also proposes a method for controlling the concentration of chlorate in the electrolyte based on this device, comprising the following steps: (1) The first electrolyte circulation tank in the multiple electrolyte circulation tanks pumps sodium chlorate solution into the electrolytic tank through a circulation pump to carry out the electrolytic reaction, converting sodium chlorate solution into sodium perchlorate solution to obtain electrolyte. The sodium chlorate solution in the first circulation tank comes from the sodium chlorate high-level tank. (2) The electrolyte enters the first electrolyte circulation tank from the outlet of the electrolytic cell. In the first circulation tank, the electrolyte level gradually rises until it reaches the overflow port. (3) When the liquid level of the first circulation tank reaches the overflow port, the electrolyte flows into the second circulation tank through the overflow pipe, and the concentration gradually decreases. Each subsequent circulation tank continues to overflow in the same way. (4) When the liquid level in the first circulation tank reaches a certain height, start the electrolyte circulation pump. The circulation pump sends the electrolyte to the electrolyte heat exchanger. The temperature is adjusted by heat exchange to ensure that the electrolyte is at a suitable temperature when it enters the electrolytic cell. (5) The electrolyte after temperature adjustment is sent back to the electrolytic cell by the circulation pump for further electrolysis reaction. The electrolyte flows into the first circulation tank through the outlet of the electrolytic cell and continues to overflow. (6) When the liquid level of the fourth electrolyte circulation tank reaches the overflow port, the electrolyte flows into the electrolyte intermediate tank through the overflow port. At this time, the chlorate concentration of the electrolyte has dropped to the qualified concentration range. It is stored and used as qualified electrolyte for subsequent processes.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes multiple electrolyte circulation tanks with tiered overflow to ensure the residence time of the electrolyte in each tank, thereby precisely controlling the gradual decrease of chlorate concentration. Simultaneously, the uniformity of electrolyte flow and the control of overflow port height and height difference between the circulation tanks ensure the accuracy of concentration adjustment, ultimately enabling the electrolyte to reach a qualified concentration and be stored stably for use in subsequent processes. Overall, this invention achieves efficient and stable regulation of electrolyte concentration, saves energy, and improves the economy of the electrolysis process and product quality. Attached Figure Description

[0012] Figure 1This is a process flow diagram of an embodiment of the present invention.

[0013] Among them, 1-electrolytic cell; 21-electrolyte circulation tank A; 22-electrolyte circulation tank B; 23-electrolyte circulation tank C; 24-electrolyte circulation tank D; 3-intermediate tank; 4-sodium chlorate high-level tank; 5-electrolyte circulation pump; 6-electrolyte heat exchanger. Detailed Implementation

[0014] The technologies in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0015] Reference Figure 1 This embodiment proposes a chlorate electrolyte concentration control device based on an electrolyte circulation tank, including an electrolytic cell 1 for converting sodium chlorate solution into sodium perchlorate solution; and multiple electrolyte circulation tanks for controlling the sodium chlorate concentration in the electrolyte. Preferably, in this embodiment, the device uses four circulation tanks, such as... Figure 1 As shown, there are four electrolyte circulation tanks: A21, B22, C23, and D24. These four tanks are arranged in a gradient from high to low, each with a certain height difference. The main outlet pipe of electrolytic cell 1 is connected to the first electrolyte circulation tank, A21, allowing the electrolyte from electrolytic cell 1 to flow into A21. Specifically, electrolytic cell 1 consists of multiple individual tanks, each connected to the main outlet pipe via an outlet. The electrolyte undergoes electrolysis... After the electrolysis reaction in the tank, the electrolyte flows into the main outlet pipe through the outlet of each individual tank, and then into the circulation tank A21 through the main outlet pipe. Each electrolyte circulation tank has an overflow port on the upper part of its inner wall, which is connected to the next adjacent electrolyte circulation tank through an overflow pipe. The electrolyte enters each electrolyte circulation tank step by step through the overflow pipe. The bottom outlet of each electrolyte circulation tank is connected to the main inlet pipe of the electrolysis tank 1 through the electrolyte circulation pump 5. The electrolyte is drawn and sent into the electrolysis tank to continue the electrolysis reaction. Specifically, the electrolyte circulation pump draws electrolyte from each circulation tank and transports it through pipelines to the main inlet pipe of the electrolytic cell, ensuring that the electrolyte circulates repeatedly within the electrolytic cell, promoting further consumption of chlorate and thus gradually reducing the concentration. The main inlet pipe also connects to the inlet of each individual tank. Each electrolyte circulation pump 5 is equipped with an electrolyte heat exchanger 6 on the pipeline from the electrolytic cell 1 to regulate the temperature of the electrolyte and ensure the inlet temperature. The electrolyte in the electrolyte circulation tank returns to the electrolytic cell after passing through the electrolyte heat exchanger.

[0016] Specifically, this embodiment also includes a sodium chlorate high-level tank 4. The outlet of the sodium chlorate high-level tank is connected to the first electrolyte circulation tank A21 among multiple electrolyte circulation tanks via a pipeline. The sodium chlorate high-level tank 4 is used to provide the initial sodium chlorate solution. The liquid flows into the pipeline through the outlet and enters the electrolyte circulation tank A21. Initially, the electrolyte circulation pump 5 at the outlet of the electrolyte circulation tank A21 sends the sodium chlorate solution to the electrolytic cell 1 to start the electrolysis reaction. The electrolyte flows into the first electrolyte circulation tank A21 through the outlet manifold to start the circulation process.

[0017] All four electrolyte circulation tanks are cylindrical in shape with the same specifications to ensure uniform flow of electrolyte within the tank. The overflow port of each electrolyte circulation tank is at the same height and is located on the upper part of the inner wall of the tank. At the same time, the height difference between any two adjacent electrolyte circulation tanks is the same, and the height difference of each electrolyte circulation tank generally does not exceed 10% of the total height of the tank.

[0018] This embodiment utilizes multiple electrolyte circulation tanks for tiered overflow, ensuring sufficient residence time of the electrolyte in each tank. This effectively controls the electrolyte concentration. In each circulation tank, the electrolyte level gradually rises until it reaches the overflow port, at which point it overflows into the next tank. Simultaneously, an electrolyte circulation pump delivers electrolyte from each circulation tank to the electrolytic cell, ensuring repeated circulation within the electrolytic cell and promoting further consumption of chlorate. As the residence time of the electrolyte in each circulation tank gradually increases, it has sufficient time to enter the electrolytic cell for further reaction, consuming chlorate and thus gradually reducing its concentration. Through this process, the chlorate concentration of the electrolyte can be gradually reduced to a qualified range, ensuring that the electrolyte quality meets the requirements of subsequent processes.

[0019] Specifically, the last electrolyte circulation tank D24 among the four electrolyte circulation tanks is connected to the intermediate electrolyte tank 3 through an overflow pipe. The intermediate electrolyte tank 3 is used to store the electrolyte overflowing from the last circulation tank as qualified electrolyte for subsequent processes.

[0020] This embodiment also includes a method for controlling the electrolyte chlorate concentration based on this device, comprising the following steps: (1) The sodium chlorate solution is pumped into the electrolytic cell 1 through the electrolyte circulation pump 5 in the electrolyte circulation tank A21 to carry out the electrolysis reaction, converting the sodium chlorate solution into sodium perchlorate solution to obtain the electrolyte. The sodium chlorate solution in the circulation tank A21 comes from the sodium chlorate high-level tank 4. (2) The electrolyte enters the electrolyte circulation tank A21 from the main outlet pipe of the electrolytic cell 1. The liquid level of the electrolyte circulation tank A21 gradually rises and overflows into the electrolyte circulation tank B22. (3) When the liquid level of electrolyte circulation tank B22 reaches a certain height, start the electrolyte circulation pump 5 at the outlet of electrolyte circulation tank B22. The circulation pump sends the electrolyte to electrolyte heat exchanger 6. The temperature is adjusted by heat exchange to ensure that the electrolyte temperature is suitable when it enters the electrolyte tank 1. (4) After temperature adjustment, the electrolyte is sent back to the electrolytic cell by the electrolyte circulation pump 5 for further electrolysis reaction. The electrolyte flows into the electrolyte circulation tank A21 through the outlet of the electrolytic cell and continues to overflow. (5) When the liquid level of electrolyte circulation tank B22 reaches the overflow port, the electrolyte flows into electrolyte circulation tank C23 through the overflow pipe, and the operation of step (4) is repeated, and each subsequent circulation tank continues to overflow in the same way. (6) As the circulation time increases, the electrolyte is repeatedly electrolyzed in the electrolytic cell, and the chlorate is continuously consumed, thereby reducing the concentration step by step. When the liquid level of the electrolyte circulation tank D24 reaches the overflow port, the electrolyte flows into the electrolyte intermediate tank 3 through the overflow port. At this time, the chlorate concentration of the electrolyte has dropped to the qualified concentration range, and it is stored and used as qualified electrolyte for subsequent processes.

[0021] In the above method, electrolytic cell 1 is used to electrolyze the sodium chlorate solution from circulation cell A21, gradually oxidizing the chlorate ions to generate sodium perchlorate solution. In this embodiment, the effective volume of the electrolytic cell is 100 L, and the sodium chlorate solution initially received by the electrolytic cell comes from sodium chlorate high-level tank 4, with an initial sodium chlorate concentration of 60 g / L. After electrolysis, the electrolyte flows through the outlet of each individual cell into the main outlet pipe and back to the first electrolyte circulation cell A21 to initiate the concentration adjustment process.

[0022] To achieve stepwise concentration control of the electrolyte, this embodiment includes four electrolyte circulation tanks, A21, B22, C23, and D24, each with a volume of 50 L. All tanks employ a cylindrical structure to minimize dead zones and ensure uniform mixing within the tank. The four circulation tanks are arranged in a gradient from high to low, with the overall height decreasing progressively. The consistent height difference between each tank allows the electrolyte to overflow smoothly to the next circulation tank based on the liquid level difference.

[0023] Each circulation tank has an overflow port at a uniform height (located at 80% of the tank height) on its top inner wall to control the residence time of the electrolyte. As the electrolyte level rises within the circulation tank with replenishment and return, it reaches the overflow port and flows into the next circulation tank via the overflow pipe, thus achieving step-by-step concentration adjustment.

[0024] Each circulation tank is connected to an electrolyte circulation pump 5 (rated flow rate 10 L / min) at its bottom outlet. This pump draws the electrolyte from the circulation tank and sends it to the electrolyte heat exchanger 6 for temperature regulation. The heat exchanger 6 ensures that the electrolyte returning to the electrolytic tank is always maintained within the optimal reaction temperature range of 60–62°C, thereby improving the electrolysis reaction rate and chlorate consumption efficiency. After temperature control, the electrolyte enters the electrolytic tank 1 to undergo another electrolysis reaction and continue consuming chlorate.

[0025] During normal operation, circulation tank A21 first receives sodium chlorate solution from high-level tank 4 and mixes it with return liquid from the electrolytic cell. As the liquid level in the tank rises to a predetermined height, circulation pump 5 in circulation tank A21 continuously pumps electrolyte into the electrolytic cell, achieving a circulating reaction and gradually reducing the chlorate concentration. When the liquid level in circulation tank A21 reaches the overflow port, the electrolyte overflows into circulation tank B22. As the liquid level in circulation tank B22 gradually rises, its circulation pump starts operating, allowing the electrolyte to repeatedly enter the electrolytic cell for continued electrolysis, further reducing the concentration. Similarly, circulation tanks C23 and D24 undergo circulation and concentration adjustment in the same manner.

[0026] When the electrolyte finally enters the circulation tank D24 and its level rises to the overflow port, it indicates that the electrolyte has undergone multiple electrolytic cycles and its chlorate concentration has dropped to the target range (20–30 g / L). At this point, the electrolyte flows through the overflow port into the intermediate electrolyte tank 3 and is stored as qualified electrolyte for use in subsequent processes.

[0027] In the above process, the residence time of the electrolyte in each circulation tank is determined by the flow rate of the circulation pump, the reflux velocity, and the overflow port height. Through the structural design of multiple tanks connected in series and step-by-step overflow, the number of circulations and reaction times of the electrolyte in different tanks are effectively differentiated, allowing the reaction consuming chlorate to proceed more fully. Experimental results show that by controlling the series connection of four circulation tanks, the electrolyte concentration can be stably reduced from the initial 60 g / L to 20–30 g / L, and the temperature control system stably controls the inlet temperature of the electrolyzer at 60–62℃, ensuring optimal reaction efficiency.

[0028] This embodiment verifies the effectiveness of the device and method of the present invention, and confirms that the method of using a multi-stage circulating tank gradient overflow combined with a circulating pump to return the electrolyzer can not only achieve precise adjustment of the electrolyte concentration, but also make full use of the depth of the electrolysis reaction, reduce energy consumption, improve production efficiency, and has good industrial application value.

Claims

1. A chlorate electrolyte concentration control device based on an electrolyte circulation tank, characterized in that, An electrolytic cell is used to convert sodium chlorate solution into sodium perchlorate solution. Multiple electrolyte circulation tanks are arranged in a gradient from high to low. The main outlet pipe of each electrolytic cell is connected to the first electrolyte circulation tank. Each electrolyte circulation tank has an overflow port and is connected to its adjacent next electrolyte circulation tank via an overflow pipe. Electrolyte enters each electrolyte circulation tank step by step through the overflow pipe. The bottom outlet of each electrolyte circulation tank is connected to the main inlet pipe of the electrolytic cell via an electrolyte circulation pump. Each electrolyte circulation pump is equipped with an electrolyte heat exchanger on its pipeline from the electrolytic cell to the electrolyte circulation tank.

2. The chlorate electrolyte concentration control device based on an electrolyte circulation tank according to claim 1, characterized in that, The device also includes a sodium chlorate high-level tank, the outlet of which is connected via a pipeline to the first electrolyte circulation tank among a plurality of electrolyte circulation tanks.

3. The chlorate electrolyte concentration control device based on an electrolyte circulation tank according to claim 1, characterized in that, The overflow ports of each electrolyte circulation tank are at the same height and are located on the upper part of the inner wall of the tank.

4. The chlorate electrolyte concentration control device based on an electrolyte circulation tank according to claim 1, characterized in that, The height difference between any two adjacent electrolyte circulation tanks is consistent.

5. The chlorate electrolyte concentration control device based on an electrolyte circulation tank according to claim 1, characterized in that, The last electrolyte circulation tank in a series of electrolyte circulation tanks is connected to the intermediate electrolyte tank via an overflow pipe.

6. A chlorate electrolyte concentration control device based on an electrolyte circulation tank according to any one of claims 1 to 5, characterized in that, The number of electrolyte circulation tanks is four.

7. A method for controlling the chlorate concentration in an electrolyte, characterized in that, The method, applied to a chlorate electrolyte concentration control device based on an electrolyte circulation tank as described in claim 6, includes the following steps: (1) The first electrolyte circulation tank pumps sodium chlorate solution into the electrolytic cell through the electrolyte circulation pump to carry out the electrolytic reaction, converting sodium chlorate solution into sodium perchlorate solution to obtain electrolyte. The sodium chlorate solution in the first circulation tank comes from the sodium chlorate high-level tank. (2) The electrolyte enters the first electrolyte circulation tank from the main outlet pipe of the electrolytic cell. In the first electrolyte circulation tank, the liquid level of the first electrolyte circulation tank gradually rises and overflows into the second electrolyte circulation tank. (3) When the liquid level of the second electrolyte circulation tank reaches a certain height, start the electrolyte circulation pump at the outlet of the second electrolyte circulation tank to send the electrolyte to the electrolyte heat exchanger. Adjust the temperature through heat exchange to ensure that the electrolyte is at a suitable temperature when it enters the electrolyte tank. (4) The electrolyte after temperature adjustment is sent back to the electrolytic cell for further electrolysis reaction. The electrolyte flows into the first circulation tank through the outlet of the electrolytic cell and continues to overflow. (5) When the liquid level of the second electrolyte circulation tank reaches the overflow port, the electrolyte flows into the third electrolyte circulation tank through the overflow pipe, and the operation of step (4) is repeated, and each subsequent electrolyte circulation tank continues to overflow in the same way. (6) When the liquid level of the fourth electrolyte circulation tank reaches the overflow port, the electrolyte flows into the electrolyte intermediate tank through the overflow port. At this time, the chlorate concentration of the electrolyte has dropped to the qualified concentration range. It is stored and used as qualified electrolyte for subsequent processes.

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