Resin regeneration end point confirmation method of condensate polishing system

Abstract

The invention discloses a resin regeneration end point confirmation method of a condensate polishing system, and the resin regeneration system used for condensate polishing comprises a negative regeneration tower and a positive regeneration tower, and an outlet alkali concentration meter and an inlet alkali concentration meter are arranged on the upper portion and the lower portion of the negative regeneration tower respectively. An outlet acid concentration meter and an inlet acid concentration meter are arranged on the upper portion and the lower portion of the positive regeneration tower respectively, and when the deviation between the real-time outlet alkali concentration and the real-time outlet alkali concentration is within + / -2%, it is judged that negative regeneration reaches the end point; when the deviation between the real-time outlet acid concentration and the real-time outlet acid concentration is within + / -2%, it is judged that positive regeneration reaches the end point; when the method is used for regenerating the resin, the terminal point of the resin regeneration can be determined based on the actual production condition, so that the time for feeding acid and alkali is controlled, and compared with a traditional method for fixing the using amount of the regenerant, the method has the advantages that the time for feeding acid and alkali can be shortened, the acid and alkali consumption is reduced, the using amount of demineralized water is reduced, the wastewater discharge amount is reduced, and wastewater emission reduction is realized.

Description

Technical Field

[0001] The invention relates to the technical field of water treatment, and in particular to a method for confirming a resin regeneration endpoint of a condensate polishing system. Background Art

[0002] Most of the domestic ion exchange resin regeneration adopts the traditional fixed regeneration agent dosage method, that is, regardless of the system water production and the changes in the ratio of anion and cation resins, the same dosage of regeneration agent is used. This regeneration process not only generally has high regeneration acid and alkali consumption, but also increases the cost of wastewater treatment.

[0003] Especially in the actual treatment process, due to the unbalanced ratio of cation and anion resins, the periodic water production of different high-speed mixed bed resins has a large deviation. If each set of resins adopts a fixed synchronous acid and alkali addition time, there will be problems such as unqualified resin regeneration or excessive acid and alkali addition, which will cause increased acid and alkali consumption and increased wastewater volume.

[0004] In view of the above-mentioned defects, the inventors of the present invention finally obtained the present invention after a long period of research and practice. Summary of the invention

[0005] In order to solve the above technical defects, the technical solution adopted by the present invention is to provide a method for confirming the end point of resin regeneration in a condensate polishing system, which is used for a resin regeneration system for condensate polishing. The resin regeneration system includes a negative regeneration tower and a positive regeneration tower. The drainage pipe at the lower part of the negative regeneration tower is provided with an outlet alkali concentration meter, and the liquid inlet pipe at the upper part of the negative regeneration tower is provided with an inlet alkali concentration meter. The drainage pipe at the lower part of the positive regeneration tower is provided with an outlet acid concentration meter, and the liquid inlet pipe at the upper part of the positive regeneration tower is provided with an inlet acid concentration meter. When the resin is regenerated by alkali through the negative regeneration tower, the real-time outlet alkali concentration of the outlet alkali concentration meter and the real-time outlet alkali concentration of the inlet alkali concentration meter are detected. When the deviation between the real-time outlet alkali concentration and the real-time outlet alkali concentration is within ±2%, it is determined that the negative regeneration of the resin through alkali has reached the end point; when the resin is regenerated by acid through the positive regeneration tower, the real-time outlet acid concentration of the outlet acid concentration meter and the real-time outlet acid concentration of the inlet acid concentration meter are detected. When the deviation between the real-time outlet acid concentration and the real-time outlet acid concentration is within ±2%, it is determined that the positive regeneration of the resin through acid has reached the end point.

[0006] Preferably, when the resin is subjected to alkali regeneration in the anion regeneration tower, the concentration of the alkali regeneration liquid entering the anion regeneration tower is 3% to 4%, and when the resin is subjected to acid regeneration in the cation regeneration tower, the concentration of the acid regeneration liquid entering the cation regeneration tower is 3% to 4%.

[0007] Preferably, the method for confirming the resin regeneration endpoint of the condensate polishing system comprises the steps of:

[0008] S1, while waiting for acid and alkali to be introduced, check that the manual valve in the system is open, the pipeline is unobstructed, the acid metering pump and the alkali metering pump are in the remote control position, and the outlet alkali concentration meter, the inlet alkali concentration meter, the outlet acid concentration meter and the inlet acid concentration meter are normal;

[0009] S2, when alkali regeneration is performed, the anion resin regeneration step sequence of the system is started, the drain valve at the bottom of the anion regeneration tower, the alkali inlet valve of the anion regeneration tower, and the resin outlet valve of the anion regeneration tower are opened, and then the alkali mixing three-way alkali inlet valve and the water inlet valve of the anion regeneration tower are opened; when acid regeneration is performed, the cation resin regeneration step sequence of the system is started, the drain valve at the bottom of the cation tower, the acid inlet valve of the cation regeneration tower, and the resin outlet valve of the cation regeneration tower are opened, and then the acid mixing three-way acid inlet valve and the water inlet valve of the cation regeneration tower are opened, and the acid metering pump and the alkali metering pump are started;

[0010] S3, when the deviation between the real-time outlet alkali concentration and the real-time outlet alkali concentration is within ±2%, the anion regeneration tower stops inputting the alkali regeneration liquid; when the deviation between the real-time outlet acid concentration and the real-time outlet acid concentration is within ±2%, the cation regeneration tower stops inputting the acid regeneration liquid;

[0011] S4, when the anion regeneration tower and the cation regeneration tower stop inputting the alkaline regeneration liquid and the acid regeneration liquid at the same time, the system enters the next replacement step.

[0012] Preferably, in step S2, the resin outlet valve of the anion regeneration tower and the resin outlet valve of the yang regeneration tower are both pulse valves, which are opened for 5 seconds every 300 seconds.

[0013] Preferably, in step S2, when adjusting the control input, the flow rate of the alkali regeneration solution is 9 t / h to 11 t / h, and the flow rate of the acid regeneration solution is 10 t / h to 12 t / h.

[0014] Preferably, when the alkaline regeneration liquid needs to be preheated, an electric hot water tank is correspondingly provided on the anion regeneration tower, and the alkaline regeneration liquid is preheated by providing a three-way regulating valve connected to the outlet of the electric hot water tank.

[0015] Preferably, in step S2, the preheating temperature of the alkaline regeneration liquid passing through the electric water tank is 30°C.

[0016] Preferably, the condensate polishing system is provided with a system pipeline flushing valve and a flushing water pump corresponding to the positive regeneration tower to achieve pipeline flushing.

[0017] Compared with the prior art, the beneficial effect of the present invention is that when the resin is regenerated by the present invention, the end point of the resin regeneration can be determined based on the actual production situation, thereby controlling the time for adding acid and alkali. Compared with the traditional fixed regeneration agent dosage method, the acid and alkali addition time can be shortened, the acid and alkali consumption can be reduced, the amount of desalted water can be reduced, and the wastewater discharge can be reduced, thereby achieving wastewater emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the resin regeneration system.

[0019] The numbers in the figure represent:

[0020] 1- anion regeneration tower; 2- yang regeneration tower; 3- separation tower; 4- outlet alkali concentration meter; 5- inlet alkali concentration meter; 6- outlet acid concentration meter; 7- inlet acid concentration meter. DETAILED DESCRIPTION

[0021] The above and other technical features and advantages of the present invention are described in more detail below in conjunction with the accompanying drawings.

[0022] Embodiment 1

[0023] like Figure 1 As shown, Figure 1 The resin regeneration endpoint confirmation method of the condensate polishing system of the present invention is used for the resin regeneration system of the condensate polishing treatment, the resin regeneration system comprises an anion regeneration tower 1 and a cation regeneration tower 2, the anion and cation resins are separated by a separation tower 3, the anion resin enters the anion regeneration tower 1 for alkali regeneration alone, the cation resin enters the cation regeneration tower 2 for acid regeneration alone, the drainage pipe at the bottom of the anion regeneration tower 1 is provided with an outlet alkali concentration meter 4, the liquid inlet pipe at the top of the anion regeneration tower 1 is provided with an inlet alkali concentration meter 5, the drainage pipe at the bottom of the cation regeneration tower 2 is provided with an outlet acid concentration meter 6, the liquid inlet pipe at the top of the cation regeneration tower 2 is provided with an inlet acid concentration meter 7, and the liquid inlet pipe at the bottom of the cation regeneration tower 2 is provided with an outlet acid concentration meter 8. Meter 7, when the resin is regenerated by alkali through the anion regeneration tower 1, the real-time outlet alkali concentration of the outlet alkali concentration meter 4 and the real-time outlet alkali concentration of the inlet alkali concentration meter 5 are detected, and when the deviation between the real-time outlet alkali concentration and the real-time outlet alkali concentration is within ±2%, it is determined that the anion regeneration of the resin through the introduction of alkali has reached the end point; when the resin is regenerated by acid through the cation regeneration tower 2, the real-time outlet acid concentration of the outlet acid concentration meter 6 and the real-time outlet acid concentration of the inlet acid concentration meter 7 are detected, and when the deviation between the real-time outlet acid concentration and the real-time outlet acid concentration is within ±2%, it is determined that the anion regeneration of the resin through the introduction of acid has reached the end point.

[0024] Preferably, when the resin is regenerated by alkali in the anion regeneration tower 1, the concentration of the alkali regeneration liquid entering the anion regeneration tower 1 is 3% to 4%, and when the resin is regenerated by acid in the cation regeneration tower 2, the concentration of the acid regeneration liquid entering the cation regeneration tower 2 is 3% to 4%.

[0025] The method for confirming the resin regeneration endpoint of the condensate polishing system comprises the steps of:

[0026] S1, during the waiting period for acid and alkali to be introduced, check that the manual valve in the system is open, the pipeline is unobstructed, the acid metering pump and the alkali metering pump are in the remote control position, and the outlet alkali concentration meter 4, the inlet alkali concentration meter 5, the outlet acid concentration meter 6 and the inlet acid concentration meter 7 are normal;

[0027] S2, when alkali regeneration is performed, the anion resin regeneration step sequence of the system is started, the drain valve at the bottom of the anion regeneration tower 1, the alkali inlet valve of the anion regeneration tower 1, and the resin outlet valve of the anion regeneration tower 1 are opened, and then the alkali mixing three-way alkali inlet valve and the water inlet valve of the anion regeneration tower 1 are opened; when acid regeneration is performed, the cation resin regeneration step sequence of the system is started, the drain valve at the bottom of the cation tower, the acid inlet valve of the cation regeneration tower 2, and the resin outlet valve of the cation regeneration tower 2 are opened, and then the acid mixing three-way acid inlet valve and the water inlet valve of the cation regeneration tower 2 are opened, and the acid metering pump and the alkali metering pump are started;

[0028] S3, when the real-time outlet alkali concentration and the real-time outlet alkali concentration deviation are within ±2%, the anion regeneration tower 1 stops inputting the alkali regeneration liquid; when the real-time outlet acid concentration and the real-time outlet acid concentration deviation are within ±2%, the cation regeneration tower 2 stops inputting the acid regeneration liquid;

[0029] S4, when the anion regeneration tower 1 and the cation regeneration tower 2 stop inputting the alkaline regeneration solution and the acid regeneration solution at the same time, the system enters the next replacement step.

[0030] In the step S2, the resin outlet valve of the anion regeneration tower 1 and the resin outlet valve of the yang regeneration tower 2 are both pulse valves, which are opened for 5 seconds every 300 seconds.

[0031] In step S2, when adjusting the control input, the flow rate of the alkali regeneration solution is 9t / h-11t / h, the flow rate of the acid regeneration solution is 10t / h-12t / h, and the concentrations of the alkali regeneration solution and the acid regeneration solution are 3%-4%.

[0032] When the alkaline regeneration liquid needs to be preheated, an electric hot water tank is correspondingly provided on the anion regeneration tower 1, and the alkaline regeneration liquid is preheated by providing a three-way regulating valve connected to the outlet of the electric hot water tank.

[0033] In the step S2, the preheating temperature of the alkaline regeneration liquid passing through the electric water tank is 30°C.

[0034] In step S2, the alkali mixing three-way alkali inlet valve forms the alkali regeneration solution by mixing an alkali solution such as sodium hydroxide and desalted water, and the alkali metering pump provides input power and controls the amount of alkali solution added. The acid mixing three-way alkali inlet valve forms the acid regeneration solution by mixing an acid solution such as sulfuric acid and desalted water, and the acid metering pump provides input power and controls the amount of acid solution added.

[0035] The condensate polishing system is provided with a system pipeline flushing valve and a flushing water pump corresponding to the positive regeneration tower 2 to achieve pipeline flushing.

[0036] When the resin is regenerated by the present invention, the end point of the resin regeneration can be determined based on the actual production situation, thereby controlling the time for adding acid and alkali. Compared with the traditional method of fixing the dosage of the regeneration agent, the time for adding acid and alkali can be shortened, the acid and alkali consumption can be reduced, the amount of desalted water can be reduced, and the amount of wastewater discharged can also be reduced, thereby achieving wastewater emission reduction.

[0037] Embodiment 2

[0038] In order to compare the present invention with the traditional regeneration method, the acid concentration of two sets of high-speed mixed bed resins in the process of simultaneous acid and alkali feeding was randomly measured on site, and the data are summarized in the following table:

[0039]

[0040] From the data, we can see that: for the first set of resins, the acid inlet concentration and the acid output concentration reached equilibrium when the acid was introduced for 45min to 50min; for the second set of resins, the acid inlet concentration and the acid output concentration reached equilibrium when the acid was introduced for 50min to 55min.

[0041] If regeneration is carried out according to the traditional method of fixed regeneration agent dosage, the first set of resins will have excessive acid for 10min to 15min, and the second set of resins will have excessive acid for 5min to 10min. This will undoubtedly increase the acid and alkali consumption during resin regeneration and increase the cost of wastewater treatment, which is not conducive to energy conservation and environmental protection.

[0042] If the endpoint confirmation is performed by adopting the present invention, when the resin is regenerated, the acid inlet concentration and the acid outlet concentration reach a balance, the acid inlet can be stopped, and the acid and alkali inlet time is shortened. Each regeneration can save 160L of acid and alkali respectively, and a total of 16 tons of acid and alkali can be saved throughout the year, and 10,000 tons of desalted water can be saved, thereby reducing the acid and alkali consumption, reducing the amount of desalted water used, and also reducing the amount of wastewater discharged, thereby achieving wastewater emission reduction.

[0043] The above description is only a preferred embodiment of the present invention, which is only illustrative and not restrictive of the present invention. Those skilled in the art understand that many changes, modifications, and even equivalences may be made to the present invention within the spirit and scope defined by the claims of the present invention, but all of them will fall within the scope of protection of the present invention.

Claims

1. A method for confirming the end point of resin regeneration in a condensate polishing system, characterized in that: A resin regeneration system for condensate polishing, the resin regeneration system comprises a negative regeneration tower and a positive regeneration tower, the drainage pipe at the lower part of the negative regeneration tower is provided with an outlet alkali concentration meter, the liquid inlet pipe at the upper part of the negative regeneration tower is provided with an inlet alkali concentration meter, the drainage pipe at the lower part of the positive regeneration tower is provided with an outlet acid concentration meter, and the liquid inlet pipe at the upper part of the positive regeneration tower is provided with an inlet acid concentration meter. When the resin is regenerated by alkali through the negative regeneration tower, the real-time outlet alkali concentration of the outlet alkali concentration meter and the real-time outlet alkali concentration of the inlet alkali concentration meter are detected, and when the deviation between the real-time outlet alkali concentration and the real-time outlet alkali concentration is within ±2%, it is determined that the negative regeneration of the resin through alkali injection has reached an end point; when the resin is regenerated by acid through the positive regeneration tower, the real-time outlet acid concentration of the outlet acid concentration meter and the real-time outlet acid concentration of the inlet acid concentration meter are detected, and when the deviation between the real-time outlet acid concentration and the real-time outlet acid concentration is within ±2%, it is determined that the positive regeneration of the resin through acid injection has reached an end point.

2. The method for confirming the resin regeneration endpoint of the condensate polishing system according to claim 1, characterized in that: When the resin is subjected to alkali regeneration in the anion regeneration tower, the concentration of the alkali regeneration liquid entering the anion regeneration tower is 3% to 4%. When the resin is subjected to acid regeneration in the cation regeneration tower, the concentration of the acid regeneration liquid entering the cation regeneration tower is 3% to 4%.

3. The method for confirming the resin regeneration endpoint of the condensate polishing system according to claim 2, characterized in that: The method for confirming the resin regeneration endpoint of the condensate polishing system comprises the steps of: S1, while waiting for acid and alkali to be introduced, check that the manual valve in the system is open, the pipeline is unobstructed, the acid metering pump and the alkali metering pump are in the remote control position, and the outlet alkali concentration meter, the inlet alkali concentration meter, the outlet acid concentration meter and the inlet acid concentration meter are normal; S2, when alkali regeneration is performed, the anion resin regeneration step sequence of the system is started, the drain valve at the bottom of the anion regeneration tower, the alkali inlet valve of the anion regeneration tower, and the resin outlet valve of the anion regeneration tower are opened, and then the alkali mixing three-way alkali inlet valve and the water inlet valve of the anion regeneration tower are opened; when acid regeneration is performed, the cation resin regeneration step sequence of the system is started, the drain valve at the bottom of the cation tower, the acid inlet valve of the cation regeneration tower, and the resin outlet valve of the cation regeneration tower are opened, and then the acid mixing three-way acid inlet valve and the water inlet valve of the cation regeneration tower are opened, and the acid metering pump and the alkali metering pump are started; S3, when the deviation between the real-time outlet alkali concentration and the real-time outlet alkali concentration is within ±2%, the anion regeneration tower stops inputting the alkali regeneration liquid; when the deviation between the real-time outlet acid concentration and the real-time outlet acid concentration is within ±2%, the cation regeneration tower stops inputting the acid regeneration liquid; S4, when the anion regeneration tower and the cation regeneration tower stop inputting the alkaline regeneration liquid and the acid regeneration liquid at the same time, the system enters the next replacement step.

4. The method for confirming the resin regeneration endpoint of the condensate polishing system according to claim 3, characterized in that: In the step S2, the resin outlet valve of the anion regeneration tower and the resin outlet valve of the yang regeneration tower are both pulse valves, which are opened for 5 seconds every 300 seconds.

5. The method for confirming the resin regeneration endpoint of the condensate polishing system according to claim 3, characterized in that: In step S2, when adjusting the control input, the flow rate of the alkali regeneration solution is 9 t / h to 11 t / h, and the flow rate of the acid regeneration solution is 10 t / h to 12 t / h.

6. The method for confirming the resin regeneration endpoint of the condensate polishing system according to claim 5, characterized in that: When the alkaline regeneration liquid needs to be preheated, an electric hot water tank is correspondingly provided on the anion regeneration tower, and the alkaline regeneration liquid is preheated by providing a three-way regulating valve connected to the outlet of the electric hot water tank.

7. The method for confirming the resin regeneration endpoint of the condensate polishing system according to claim 6, characterized in that: In the step S2, the preheating temperature of the alkaline regeneration liquid passing through the electric water tank is 30°C.

8. The method for confirming the resin regeneration endpoint of the condensate polishing system according to claim 3, characterized in that: The condensate polishing system is provided with a system pipeline flushing valve and a flushing water pump corresponding to the positive regeneration tower to achieve pipeline flushing.

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