A process for adjusting the pH of a heavy-chelating resin after regeneration and transformation

Abstract

A method for adjusting the pH of a chelating resin after heavy metal removal and regeneration is disclosed in this application. The method allows for precise adjustment of the resin column's pH value to between 6 and 8. After the resin undergoes alkaline conversion, a pH adjustment process is initiated, employing a combination of alkaline water drainage and recovery, and weak acid circulation for precise pH adjustment. This invention features a simple process, high degree of automation, reduced operating costs, faster resin regeneration and regeneration, and improved resin system stability and efficiency. It represents a pioneering application not only in chelating resin systems for removing heavy metal pollutants in the new energy industry but also in the resin industry for precisely adjusting the pH value after regeneration.

Description

Technical Field

[0001] This invention relates to the field of chelating resin regeneration technology in the new energy industry, specifically to a process method for adjusting the pH of de-gravity chelating resin after regeneration and transformation. Background Technology

[0002] The wastewater to be treated is high-salt, high-nickel, cobalt, and manganese heavy metal wastewater generated during the production of a ternary precursor. Sodium-type chelating resin is used for chelation adsorption and removal. After the resin is saturated, acid regeneration and alkali conversion are required before it can be reused in the system.

[0003] The operation of the resin has strict pH requirements; a pH of 5-8 is necessary to achieve good adsorption and weight removal. However, during the acid-base regeneration of the resin, it is difficult to achieve uniform mixing of acid and base within the resin column. This necessitates the addition of a relatively excessive amount of liquid alkali during the alkali transition to maintain a strongly alkaline environment throughout the resin column, ensuring the transition effect. This makes it difficult to maintain a pH of 5-8 within the resin column after the transition, and the pH is generally above 11. It is necessary to continue the regeneration process by adding small amounts of dilute acid and alkali to adjust the pH. However, the industry-standard method inherent in this resin system is extremely difficult to precisely adjust the pH to 5-8, and it is easy to add too much acid or alkali. Furthermore, if too much acid is added during pH adjustment, it can lead to resin transition failure, requiring a restart, which is extremely labor-intensive and time-consuming. A large margin needs to be designed to balance the time consumption, increasing investment and operating costs.

[0004] To this end, the present invention has creatively designed a process method specifically for adjusting the pH of the resin column after regeneration and transformation. This not only solves the problem of the difficulty in accurately adjusting the pH after the resin regeneration and transformation is completed, but also greatly facilitates operation, significantly improves operating efficiency, and can recover and reuse liquid alkali, saving the investment cost caused by the need for a larger design margin of the resin system. At the same time, it reduces the operating cost caused by the excessive use of acid and alkali due to the difficulty in accurately controlling the pH. Summary of the Invention

[0005] In order to overcome the shortcomings of the above-mentioned technology, the present invention provides a method for adjusting the pH of the regeneration and transformation process of the de-chelating resin.

[0006] The technical solution of the present invention: a process method for adjusting the pH of a de-chelating resin after regeneration and transformation, characterized by comprising the following steps: S1. A pit, a liquid alkali storage tank, and a reuse pipeline are sequentially connected to the resin column. The pit is equipped with a pit pump and a liquid level sensor B. A diaphragm valve and an air vent valve are installed at the pipeline between the pit and the resin column. The diaphragm valve is a manual shut-off valve for maintenance of the air vent valve and is a normally open valve during normal system operation. An alkali addition pump is installed between the liquid alkali storage tank and the reuse pipeline. After the resin acid regeneration and alkali conversion are completed, the next step is automatically initiated. The air vent valve of the resin column is automatically opened to start venting, and the alkaline water in the resin column is discharged into the pit. After the venting time reaches the preset time, the alkaline water in the resin column is emptied, and the air vent valve automatically closes. S2. After the sump level gauge detects the pump start level, it automatically starts the sump pump to pump the alkaline water from the sump into the liquid alkali storage tank, and the alkaline water can be reused in other processes as needed. S3. A resin pH adjustment tank connected to the resin column pipeline is provided. A circulation pipeline and a return pipeline are provided between the resin pH adjustment tank and the resin column. The circulation pipeline is equipped with a pH adjustment circulation pump, a diaphragm valve, and a pneumatic valve A. The diaphragm valve is a manual shut-off valve for maintenance of pneumatic valve A and is normally open during normal system operation. The return pipeline is equipped with a diaphragm valve, a pneumatic valve B, and an online pH meter A. The diaphragm valve is a manual shut-off valve for maintenance of pneumatic valve B and is normally open during normal system operation. The resin pH adjustment tank is equipped with a liquid level sensor A, an online pH meter B, and a stirrer. It is externally connected to a tap water pipeline, an acid metering pump, and an alkali metering pump. A manual valve and an electric flow regulating valve A are installed between the acid metering pump and the resin pH adjusting tank. The manual valve is a maintenance shut-off valve for the electric flow regulating valve A and is normally open during normal system operation. A manual valve and an electric flow regulating valve B are installed between the alkali metering pump and the resin pH adjusting tank. The manual valve is a maintenance shut-off valve for the electric flow regulating valve B and is normally open during normal system operation. A manual valve and a water supply electric valve are installed between the tap water pipeline and the resin pH adjusting tank. The manual valve is a maintenance shut-off valve for the water supply electric valve and is normally open during normal system operation. The liquid level sensor A detects the liquid level of the resin pH adjustment tank. When the liquid level set value reaches the preset water replenishment level, the water replenishment electric valve is automatically opened to replenish the resin pH adjustment tank to the set liquid level, and then the water replenishment electric valve is closed, so as to dynamically maintain the liquid level of the resin pH adjustment tank at the set liquid level at all times. The online pH meter B detects the pH of the resin pH adjustment tank. When the pH is greater than 7, the PLC automatically turns on the agitator, acid metering pump and electric flow regulating valve A. Based on the pH value detected by the online pH meter B, the PLC automatically adjusts the acid flow rate to adjust the pH value of the resin pH adjustment tank to the range of 5 to 7. Then, the PLC stops the acid metering pump and closes the electric flow regulating valve A. After a preset time, the PLC turns off the agitator and dynamically maintains the pH of the resin pH adjustment tank within the set range at all times. S4. After the alkaline water in the resin column is drained and the pneumatic valve for venting is automatically closed, the next step is automatically initiated. The liquid level in the resin pH adjustment tank is maintained at the pump start level set value. The pneumatic valve A is automatically opened, and then the resin pH adjustment tank circulation pump is automatically started to pump the weak acid water from the resin pH adjustment tank into the resin column, and then returns to the resin pH adjustment tank through the return pipeline for circulation. The resin column is equipped with an exhaust pipe, and the exhaust pipe is equipped with a slow-opening and slow-closing exhaust valve (9). After the pH adjustment circulation pump is detected to start, the slow-opening and slow-closing exhaust valve (9) slowly opens. After a predetermined time, the exhaust pipe discharges water into the pit, and then the slow-opening and slow-closing exhaust valve (9) slowly closes.

[0007] S5. After the operation of the circulating pH adjustment of the resin column is started in step S4, as described in step S3, the liquid level and pH value of the resin pH adjustment tank are always kept within the set range. The online pH meter B installed in the resin pH adjustment tank works in PLC linkage with the acid metering pump and the electric flow regulating valve A to control the flow rate of the added dilute acid. During the circulating operation of the resin pH adjustment tank, the pH of the water in the resin pH adjustment tank is always controlled at 5~7 until the online pH meter A in the circulation pipeline detects that the pH value is maintained in the range of 5~8 and the maintenance time reaches the preset time. At this time, the pH value of the water in the resin column has been adjusted to 5~8, and the pH adjustment is completed. The pH adjustment circulation pump and the pneumatic valve A stop and close in sequence. That is, the weak acid circulating pH adjustment system automatically stops running, and the central control page alarms to remind the central control operator that the resin column has been regenerated and transformed and the pH adjustment is completed, and it enters the standby state.

[0008] A further feature of the present invention is that the process method further includes a backup alkali addition adjustment system, which includes an alkali metering pump connected to the resin pH adjustment tank pipeline, an electric flow regulating valve B, and a manual valve. The manual valve is a maintenance manual shut-off valve for the electric flow regulating valve B and is normally open when the system is running normally. In step S4, after the weak acid circulation pH adjustment system of the resin pH adjustment tank and resin column is automatically turned on, if an abnormal situation occurs where the pH value in the resin pH adjustment tank is lower than the set lower limit of 5 due to excessive acid adjustment, the pH circulation pump and pneumatic valve A will stop and close in sequence, and an alarm will be issued to the central control operator on the central control page. At this time, the online pH meter B, the alkali metering pump, and the electric flow regulating valve B installed in the resin pH adjustment tank will start to work in PLC linkage to control the flow rate of added dilute alkali, readjust the pH of the resin pH adjustment tank back to 5~7, and maintain it for a preset time. Then, the alkali metering pump and the electric flow regulating valve B will stop and close, and the weak acid circulation pH adjustment system in step S4 will be restarted to continue to circulate and adjust the pH of the resin column.

[0009] The above technical solution is adopted to prevent remedial alkali adjustment measures from being implemented in case of system malfunction. The reason for first stopping the weak acid circulation pH adjustment system and issuing an alarm to the central control system before starting the backup alkali addition system is that acidic water with excessively low pH entering the resin column will disrupt the resin's alkali conversion effect, leading to a decrease in the resin's ability to remove heavy metal pollutants. To avoid this, it is necessary to prevent excessively acidic water from entering the resin. Only after the pH value in the resin's pH adjustment tank returns to the preset range can the weak acid circulation pH adjustment system be restarted.

[0010] The reason why the weak acid circulation pH adjustment system must be stopped and an alarm sent to the central control system before the backup alkali addition system is started is that acidic water with too low a pH value entering the resin column will destroy the alkali conversion effect of the resin, resulting in a decrease in the resin's ability to remove heavy metal pollutants. In order to avoid this situation, it is necessary to prevent the acidic water from entering the resin. The weak acid circulation pH adjustment system can only be restarted after the pH value in the resin pH adjustment tank has returned to the preset range.

[0011] The beneficial effects of this invention are as follows: The setup and method described in this application enable precise adjustment of the pH value of the resin column to between 5 and 8. After the resin-alkali conversion is completed, the pH adjustment process begins. This process employs an alkaline water drainage and recovery + weak acid circulation pH adjustment method for precise pH adjustment. After the resin-alkali conversion, the pH in the resin column is typically above 11. First, the resin column drainage valve is opened, releasing the alkaline water from the resin column into a pit. The pit pump, through a liquid level interlock, automatically pumps the alkaline water into a liquid alkali storage tank for reuse in other treatment processes. Then, the water from the resin pH adjustment tank is pumped into the resin column for circulation. By linking the pH meter in the pH adjustment tank with the acid addition pump, the pH of the circulating water is precisely controlled and adjusted to between 5 and 8, until the pH value within the resin column is ultimately stabilized at 5-8. Attached Figure Description

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

[0013] Among them, 1. Electric flow regulating valve A; 2. Electric flow regulating valve B; 3. Water replenishment electric valve; 4. Liquid level sensor A; 5. Agitator; 6. Liquid level sensor B; 7. Air exhaust valve; 8. Pneumatic valve B; 9. Slow-opening and slow-closing exhaust valve; 10. Pneumatic valve A; 11. Online pH meter A; 12. Online pH meter B.

[0014] To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual size of the product. Furthermore, the accompanying drawings are for illustrative purposes only and should not be construed as limiting this patent. Detailed Implementation

[0015] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings. Other related parts can be referred to the general design. In the absence of conflict, the embodiments and technical features in the embodiments of this application can be combined with each other to obtain new embodiments.

[0016] like Figure 1 As shown, a method for adjusting the pH of a regenerated and transformed heavy chelating resin is characterized by the following steps: S1. A pit, a liquid alkali storage tank, and a reuse pipeline are connected to the resin column in sequence. The pit is equipped with a pit pump and a liquid level sensor B (6). A diaphragm valve and an air exhaust valve (7) are installed at the pipeline between the pit and the resin column. The diaphragm valve is a manual shut-off valve for maintenance of the air exhaust valve (7). It is a normally open valve when the system is running normally. An alkali addition pump is installed between the liquid alkali storage tank and the reuse pipeline. After the resin acid regeneration and alkali conversion is completed, it automatically enters the next step and automatically opens the air vent valve (7) of the resin column to start venting, discharging the alkali water in the resin column into the pit. After the venting time reaches the preset time, the alkali water in the resin column is vented and the air vent valve (7) automatically closes. S2. After the sump level gauge detects the pump start level, it automatically starts the sump pump to pump the alkaline water from the sump into the liquid alkali storage tank, and the alkaline water can be reused in other processes as needed. S3. A resin pH adjustment tank connected to the resin column pipeline is set up. The resin pH adjustment tank is equipped with a stirrer (5). A circulation pipeline and a return pipeline are set between the resin pH adjustment tank and the resin column. The circulation pipeline is equipped with a pH adjustment circulation pump, a diaphragm valve, and a pneumatic valve A (10). The diaphragm valve is a maintenance manual shut-off valve for the pneumatic valve A (10). It is a normally open valve when the system is running normally. The return pipeline is equipped with a diaphragm valve, a pneumatic valve B (8), and an online pH meter A (11). The diaphragm valve is a maintenance manual shut-off valve for the pneumatic valve B (8). It is a normally open valve when the system is running normally. The resin pH adjustment tank is equipped with a liquid level sensor A (4), an online pH meter B (12), and a stirrer (5). It is connected to a tap water pipeline, an acid metering pump, and an alkali metering pump. A manual valve and an electric flow regulating valve A (1) are provided between the acid metering pump and the resin pH adjusting tank. The manual valve is a maintenance manual shut-off valve for the electric flow regulating valve A (1) and is normally open when the system is running normally. A manual valve and an electric flow regulating valve B (2) are provided between the alkali metering pump and the resin pH adjusting tank. The manual valve is a maintenance manual shut-off valve for the electric flow regulating valve B (2) and is normally open when the system is running normally. A manual valve and a water supply electric valve (3) are provided between the tap water pipeline and the resin pH adjusting tank. The manual valve is a maintenance manual shut-off valve for the water supply electric valve (3) and is normally open when the system is running normally. The liquid level sensor A (4) detects the liquid level of the resin pH adjustment tank. When the liquid level setting value reaches the preset water replenishment level, the water replenishment electric valve (3) is automatically opened to replenish the resin pH adjustment tank to the set liquid level, and then the water replenishment electric valve (3) is closed to dynamically maintain the liquid level of the resin pH adjustment tank at the set liquid level at all times. The online pH meter B (12) detects the pH of the resin pH adjustment tank. When pH > 7, the PLC automatically turns on the agitator (5), the acid metering pump and the electric flow regulating valve A (1). According to the pH value detected by the online pH meter B (12), the acid flow rate is automatically adjusted to adjust the pH value of the resin pH adjustment tank to the range of 5 to 7. Then the acid metering pump is stopped and the electric flow regulating valve A (1) is closed. After a preset time, the agitator is turned off, and the pH of the resin pH adjustment tank is dynamically maintained within the set range at all times. S4. After the alkaline water in the resin column is drained and the pneumatic valve (7) is automatically closed, the next step is automatically entered. The liquid level of the resin pH adjustment tank is maintained at the pump start liquid level setting value. The pneumatic valve A (10) is automatically opened. Then the resin pH adjustment tank circulation pump is automatically started to pump the weak acid water from the resin pH adjustment tank into the resin column, and then returns to the resin pH adjustment tank through the return pipeline for circulation operation. The resin column is equipped with an exhaust pipe, and the exhaust pipe is equipped with a slow-opening and slow-closing exhaust valve (9). After the pH adjustment circulation pump is detected to start, the slow-opening and slow-closing exhaust valve (9) slowly opens. After a predetermined time, the exhaust pipe discharges water into the pit, and then the slow-opening and slow-closing exhaust valve (9) slowly closes.

[0017] S5. After the operation of the pH adjustment of the resin column in step S4 is started, as described in step S3, the liquid level and pH value of the resin pH adjustment tank are always kept within the set range. The online pH meter B (12) installed in the resin pH adjustment tank works in PLC linkage with the acid metering pump and the electric flow regulating valve A (1) to control the flow rate of the added dilute acid. During the operation of the resin pH adjustment tank, the pH of the water in the resin pH adjustment tank is always controlled to be 5~7 until the online pH meter A (11) in the circulation pipeline detects that the pH value is maintained in the range of 5~8 and the maintenance time reaches the preset time. At this time, the pH value of the water in the resin column has been adjusted to 5~8 and the pH adjustment is completed. The pH adjustment circulation pump and the pneumatic valve A (10) are stopped and closed in turn. That is, the weak acid circulation pH adjustment system automatically stops running and the central control page alarms to remind the central control operator that the resin column has been regenerated and transformed and the pH adjustment is completed, and it enters the standby state.

[0018] The process method also includes a backup alkali addition adjustment system, which includes an alkali metering pump connected to the resin pH adjustment tank pipeline, an electric flow regulating valve B (2), and a manual valve. The manual valve is a maintenance manual shut-off valve for the electric flow regulating valve B (2), and is a normally open valve when the system is running normally. After the pH adjustment system of the resin pH tank and resin column is automatically turned on in step S4, when an abnormal situation occurs where the pH value in the resin pH tank is lower than the set lower limit of 5 due to excessive acid adjustment, the pH adjustment circulation pump and pneumatic valve A (10) will stop and close in sequence, and an alarm will be issued to the central control operator on the central control page. At this time, the online pH meter B (12) installed in the resin pH tank, the alkali metering pump, and the electric flow regulating valve B (2) will start PLC linkage to control the flow rate of added dilute alkali, readjust the pH of the resin pH tank back to 5~7, and maintain it for a preset time. Then, the alkali metering pump and the electric flow regulating valve B (2) will stop and close in sequence, restart the pH adjustment system of the weak acid circulation in step S4, and continue to circulate to adjust the pH of the resin column.

[0019] The above technical solution is adopted to prevent remedial alkali adjustment measures from being implemented in case of system malfunction. The reason for first stopping the weak acid circulation pH adjustment system and issuing an alarm to the central control system before starting the backup alkali addition system is that acidic water with excessively low pH entering the resin column will disrupt the resin's alkali conversion effect, leading to a decrease in the resin's ability to remove heavy metal pollutants. To avoid this, it is necessary to prevent excessively acidic water from entering the resin. Only after the pH value in the resin's pH adjustment tank returns to the preset range can the weak acid circulation pH adjustment system be restarted.

[0020] The setup and method described in this application enable precise adjustment of the pH value of the resin column to between 5 and 8. After the resin undergoes alkaline conversion, a pH adjustment process is initiated. This process employs an alkaline water drainage and recovery combined with a weak acid circulation method for precise pH adjustment. After the resin undergoes alkaline conversion, the pH in the resin column is typically above 11. The resin column drainage valve is opened, releasing the alkaline water into a sump. The sump pump, via a level interlock, automatically pumps the alkaline water into a liquid alkali storage tank for reuse in other treatment processes. Then, water from the pH adjustment tank is pumped into the resin column for circulation. Through the linkage between the pH meter in the pH adjustment tank and the acid pump, the pH of the circulating water is precisely controlled and adjusted to between 5 and 8, ultimately stabilizing the pH value within the resin column at 5-8.

[0021] Zhejiang Weiming Shengqing Energy New Materials Co., Ltd. has already applied this invention process. Before the installation of this invention process, after the resin regeneration and transformation was completed, a specialist was required to adjust the pH. This involved manually turning on the acid and alkali pumps to pump the acid and alkali into the resin column using the regeneration acid and alkali addition pipelines built into the resin system. Since the resin column itself did not have any mixing device, it relied entirely on static neutralization reaction. The reaction time was long and it was difficult to achieve uniformity. Therefore, the amount of acid and alkali used could not be precisely controlled and it was easy to overdo it. If too much acid was added, alkali had to be added for neutralization or even the transformation had to be restarted. If too much alkali was added, acid had to be added. This required repeated addition of acid or alkali and waiting for the neutralization reaction to be completed. It usually took 2 to 3 days to complete the pH adjustment process. Each pH adjustment used as much as 500L to 1000L of 98% concentrated sulfuric acid and as much as 400L to 1000L of 32% liquid alkali. After adopting this invention, the pH adjustment time is only 4 to 10 hours, the system's water treatment capacity is nearly doubled, and the system's operating capacity is greatly improved. The amount of 98% concentrated sulfuric acid used is usually only 200 to 500 L, and almost no additional liquid alkali is needed. Not considering the reuse of liquid alkali and the saving of electricity, the cost of acid and alkali addition alone, calculated based on the market price of concentrated sulfuric acid of about 0.8 yuan / L and the market price of 32% liquid alkali of about 1.7 yuan / L, can save about 85% of the operating cost for adjusting the pH of the resin.

[0022] The above description is merely a preferred embodiment of the present invention and should not be used to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0023] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A method for adjusting the pH of a de-chelating resin after regeneration and transformation, characterized in that... Includes the following steps: S1. A pit, a liquid alkali storage tank, and a reuse pipeline are connected to the resin column in sequence. The pit is equipped with a pit pump and a liquid level sensor B (6). A diaphragm valve and an air exhaust valve (7) are installed at the pipeline between the pit and the resin column. The diaphragm valve is a manual shut-off valve for maintenance of the air exhaust valve (7). It is a normally open valve when the system is running normally. An alkali addition pump is installed between the liquid alkali storage tank and the reuse pipeline. After the resin acid regeneration and alkali conversion is completed, it automatically enters the next step and automatically opens the air vent valve (7) of the resin column to start venting, discharging the alkali water in the resin column into the pit. After the venting time reaches the preset time, the alkali water in the resin column is vented and the air vent valve (7) automatically closes. S2. After the sump level gauge detects the pump start level, it automatically starts the sump pump to pump the alkaline water from the sump into the liquid alkali storage tank, and the alkaline water can be reused in other processes as needed. S3. A resin pH adjustment tank connected to the resin column pipeline is provided. A circulation pipeline and a return pipeline are provided between the resin pH adjustment tank and the resin column. A pH adjustment circulation pump, a diaphragm valve, and a pneumatic valve A (10) are provided at the circulation pipeline. The diaphragm valve is a manual shut-off valve for maintenance of the pneumatic valve A (10). It is a normally open valve when the system is running normally. A diaphragm valve, a pneumatic valve B (8), and an online pH meter A (11) are provided at the return pipeline. The diaphragm valve is a manual shut-off valve for maintenance of the pneumatic valve B (8). It is a normally open valve when the system is running normally. A liquid level sensor A (4), an online pH meter B (12), and a stirrer (5) are provided inside the resin pH adjustment tank. A tap water pipeline, an acid metering pump, and an alkali metering pump are connected to the outside. A manual valve and an electric flow regulating valve A (1) are provided between the acid metering pump and the resin pH adjusting tank. The manual valve is a maintenance manual shut-off valve for the electric flow regulating valve A (1) and is normally open when the system is running normally. A manual valve and an electric flow regulating valve B (2) are provided between the alkali metering pump and the resin pH adjusting tank. The manual valve is a maintenance manual shut-off valve for the electric flow regulating valve B (2) and is normally open when the system is running normally. A manual valve and a water supply electric valve (3) are provided between the tap water pipeline and the resin pH adjusting tank. The manual valve is a maintenance manual shut-off valve for the water supply electric valve (3) and is normally open when the system is running normally. The liquid level sensor A (4) detects the liquid level of the resin pH adjustment tank. When the liquid level setting value reaches the preset water replenishment level, the water replenishment electric valve (3) is automatically opened to replenish the resin pH adjustment tank to the set liquid level, and then the water replenishment electric valve (3) is closed to dynamically maintain the liquid level of the resin pH adjustment tank at the set liquid level at all times. The online pH meter B (12) detects the pH of the resin pH adjustment tank. When pH > 7, the PLC automatically turns on the agitator (5), the acid metering pump and the electric flow regulating valve A (1). According to the pH value detected by the online pH meter B (12), the acid flow rate is automatically adjusted to adjust the pH value of the resin pH adjustment tank to the range of 5 to 7. Then the acid metering pump is stopped and the electric flow regulating valve A (1) is closed. After a preset time, the agitator is turned off, and the pH of the resin pH adjustment tank is dynamically maintained within the set range at all times. S4. After the alkaline water in the resin column is drained and the pneumatic valve (7) is automatically closed, the next step is automatically entered. The liquid level of the resin pH adjustment tank is maintained at the pump start liquid level setting value. The pneumatic valve A (10) is automatically opened. Then the resin pH adjustment tank circulation pump is automatically started to pump the weak acid water from the resin pH adjustment tank into the resin column, and then returns to the resin pH adjustment tank through the return pipeline for circulation operation. The resin column is equipped with an exhaust pipe, and the exhaust pipe is equipped with a slow-opening and slow-closing exhaust valve (9). After the pH adjustment circulation pump is detected to start, the slow-opening and slow-closing exhaust valve (9) slowly opens. After a predetermined time, the exhaust pipe discharges water into the pit, and the slow-opening and slow-closing exhaust valve (9) slowly closes. S5. After the operation of the pH adjustment of the resin column in step S4 is started, as described in step S3, the liquid level and pH value of the resin pH adjustment tank are always kept within the set range. The online pH meter B (12) installed in the resin pH adjustment tank works in PLC linkage with the acid metering pump and the electric flow regulating valve A (1) to control the flow rate of the added dilute acid. During the operation of the resin pH adjustment tank, the pH of the water in the resin pH adjustment tank is always controlled to be 5~7 until the online pH meter A (11) in the circulation pipeline detects that the pH value is maintained in the range of 5~8 and the maintenance time reaches the preset time. At this time, the pH value of the water in the resin column has been adjusted to 5~8 and the pH adjustment is completed. The pH adjustment circulation pump and the pneumatic valve A (10) are stopped and closed in turn. That is, the weak acid circulation pH adjustment system automatically stops running and the central control page alarms to remind the central control operator that the resin column has been regenerated and transformed and the pH adjustment is completed, and it enters the standby state.

2. The process method for adjusting the pH of a de-chelating resin after regeneration and transformation according to claim 1, characterized in that: The process method also includes a backup alkali addition adjustment system, which includes an alkali metering pump connected to the resin pH adjustment tank pipeline, an electric flow regulating valve B (2), and a manual valve. The manual valve is a maintenance manual shut-off valve for the electric flow regulating valve B (2), and is a normally open valve when the system is running normally. After the weak acid circulation pH adjustment system of the resin pH adjustment tank and resin column is automatically turned on in step S4, when an abnormal situation occurs where the pH value in the resin pH adjustment tank is lower than the set lower limit of 5 due to excessive acid adjustment, the pH circulation pump and pneumatic valve A (10) will stop and close in sequence, and an alarm will be issued to the central control operator on the central control page. At this time, the online pH meter B (12) installed in the resin pH adjustment tank, the alkali metering pump, and the electric flow regulating valve B (2) will start PLC linkage to control the flow rate of added dilute alkali, readjust the pH of the resin pH adjustment tank back to 5~7, and maintain it for a preset time. Then, the alkali metering pump and the electric flow regulating valve B (2) will stop and close in sequence, restart the weak acid circulation pH adjustment system in step S4, and continue to circulate and adjust the pH of the resin column.

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