Resin regeneration waste liquid treatment system and method

Abstract

The invention provides a resin regeneration waste liquid treatment system and method.The system comprises a water outlet pool, a filtering assembly, a resin adsorption tower and a softened water treatment assembly which are sequentially connected in series through pipelines, and the softened water treatment assembly communicates with the water outlet pool through a backflow pipe; the softened water treatment assembly comprises a softening tank and a coagulation and flocculation unit which are sequentially connected in series through a pipeline. According to the invention, the hardness of the resin regeneration liquid can be reduced, the impact of the resin regeneration liquid on the front-end process can be reduced, the operation load of the front-end process section can be reduced, the agent dosage of the front-end process section can be reduced, and the method has the advantages of stable operation effect, system impact reduction and operation cost reduction.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a resin regeneration waste liquid treatment system and method. Background Art

[0002] After the ion exchange resin is saturated, it needs to be regenerated. Waste liquid will be produced after resin regeneration. The waste liquid from resin regeneration is a toxic and harmful waste. If it is not handled properly, it will have a certain impact on the environment and human body. First, the waste liquid from resin regeneration contains a large amount of organic matter. If it is directly discharged into the water body, it will cause eutrophication of the water body and destroy the water ecological balance. Secondly, the waste liquid from resin regeneration may also contain harmful substances such as heavy metals, which have a certain impact on the environment and human health.

[0003] At present, there is also a practice of returning the waste liquid from resin regeneration to the front end of the system for circulation treatment. However, resin regeneration is intermittent, and the water volume of the waste liquid from resin regeneration is large, the hardness is often very high, and it contains a large amount of acid and alkali. Once it flows back to the front end of the system, it will have a great impact on the front-end process, thereby affecting the effluent water quality of the front-end process section, making the entire system unstable, and easily causing the resin to frequently adsorb and saturate. Secondly, since the high-hardness resin regeneration waste liquid enters the front end, the water quality of the front-end inlet water fluctuates, affecting the hardness concentration of the front-end inlet water, resulting in frequent adjustments to the dosage of the reagent, and a large dosage. The control requirements for the dosage of the front-end process are high. Once the dosage fluctuates, the hardness of the inlet water of the ion exchange resin will increase, which will easily cause the resin to frequently adsorb and saturate, increase the frequency of regeneration, and thus form a vicious circle, resulting in increased reagent costs. Summary of the invention

[0004] The purpose of the present invention is to provide a resin regeneration waste liquid treatment system and method, which can reduce the hardness of the resin regeneration liquid, reduce the impact of the resin regeneration liquid on the front-end process, reduce the operating load of the front-end process section, and reduce the amount of reagents added in the front-end process section. It has the advantages of stable operating effect, reduced system impact and reduced operating cost.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a resin regeneration waste liquid treatment system, which includes: a water outlet tank, a filtering component, a resin adsorption tower and a softened water treatment component connected in series through pipes, the softened water treatment component is connected to the water outlet tank through a reflux pipe, and the softened water treatment component includes a softening tank and a coagulation and flocculation unit connected in series through pipes.

[0006] Optionally, the coagulation and flocculation unit includes a coagulation tank, a flocculation tank and a sedimentation tank which are sequentially connected in series through pipelines.

[0007] Optionally, the softened water treatment component includes a sodium carbonate dosing component and a sodium hydroxide dosing component, the dosing port of the sodium carbonate dosing component leads to the softening tank, and the dosing port of the sodium hydroxide dosing component leads to the softening tank.

[0008] Optionally, the softened water treatment component includes a pH correction tank, which is connected to the coagulation and flocculation unit and is located in the downstream direction of the coagulation and flocculation unit.

[0009] Optionally, the resin regeneration waste liquid treatment system includes a sludge treatment component, which includes a sludge thickening tank and a dehydration unit connected by a pipeline, and the sludge thickening tank is connected to the softened water treatment component through a pipeline for collecting and treating the sludge of the softened water treatment component.

[0010] Optionally, the resin regeneration waste liquid treatment system includes a high-density tank, the water outlet of the high-density tank is connected to the water outlet tank through a pipeline, and the mud outlet of the high-density tank is connected to the sludge thickening tank through a pipeline.

[0011] Optionally, the filtration assembly includes a shallow sand filter, an ozone tower, an activated carbon filter and an ultrafiltration device which are sequentially connected in series through a pipeline, and the ultrafiltration device is connected to the resin adsorption tower through a pipeline.

[0012] Optionally, the resin regeneration waste liquid treatment system includes a regeneration liquid neutralization tank, which is connected to the resin adsorption tower through a pipeline, and the regeneration liquid neutralization tank is connected to the softening tank through a pipeline, and the regeneration liquid neutralization tank is located between the resin adsorption tower and the softening tank.

[0013] Based on another aspect of the present invention, the present invention further provides a resin regeneration waste liquid treatment method, which is applied to the resin regeneration waste liquid treatment system as described above, and the resin regeneration waste liquid treatment method comprises:

[0014] The resin adsorption tower produces regeneration liquid;

[0015] The regeneration liquid is sequentially passed into the softening water treatment component, the water outlet tank and the filter component;

[0016] The effluent from the filtration assembly is transported to the resin adsorption tower;

[0017] When the regeneration liquid is passed into the softening tank of the softening water treatment component, sodium carbonate and sodium hydroxide are added into the softening tank to remove hardness and adjust the pH value of the liquid in the softening tank to 11.3-12.0.

[0018] Optionally, the pH value of the effluent from the softening water treatment component is adjusted to 6.0-9.0.

[0019] As configured above, the present invention softens the resin regeneration liquid and adjusts the pH value through a softening water treatment component, thereby reducing the hardness of the resin regeneration liquid, reducing the impact of the resin regeneration liquid on the front-end process, reducing the operating load of the front-end process section, making the effluent water quality of the front-end process section stable and up to standard, avoiding frequent adsorption saturation of the resin, and reducing the amount of reagents added in the front-end process section. In summary, the present invention avoids frequent adjustments to the amount of reagents added, reduces the control requirements for the amount of reagents added in the front-end process, simplifies the operation of the water treatment system, and has the advantages of stable operation effect, reduced system impact, and reduced operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Those skilled in the art should understand that the drawings are provided for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0021] Figure 1 Schematic diagram of a resin regeneration waste liquid treatment system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In this document, unless otherwise specified, the terms "upper", "lower", "left", "right", "inside", "outside", "front", "back", "top", "bottom", etc. are used to indicate directions or positional relationships based on the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction and operation. Therefore, they cannot be understood as limiting the present invention.

[0023] The specific implementation of the present invention will be described in more detail below in conjunction with the schematic diagram. The advantages and features of the present invention will become clearer based on the following description. It should be noted that the drawings are all in a very simplified form and are not in exact proportions, and are only used to facilitate and clearly assist in explaining the purpose of the embodiments of the present invention.

[0024] Figure 1 This is a schematic diagram of a resin regeneration waste liquid treatment system according to an embodiment of the present invention. Figure 1 The embodiment of the present invention provides a resin regeneration waste liquid treatment system, which includes a water outlet tank, a filter component, a resin adsorption tower and a softening water treatment component connected in series through pipelines. The softening water treatment component is connected to the water outlet tank through a reflux pipe. The softening water treatment component includes a softening tank and a coagulation and flocculation unit connected in series through pipelines. The coagulation and flocculation unit includes a coagulation tank, a flocculation tank and a sedimentation tank connected in series through pipelines. The softening water treatment component includes a sodium carbonate dosing component and a sodium hydroxide dosing component. The dosing port of the sodium carbonate dosing component leads to the softening tank, and the dosing port of the sodium hydroxide dosing component leads to the softening tank, which is used to remove the calcium and magnesium hardness in the liquid in the softening tank and adjust the pH value of the liquid in the softening tank to 11.3-12.0.

[0025] The softened water treatment component also includes a pH adjustment tank, which is connected to the coagulation and flocculation unit and is located downstream of the coagulation and flocculation unit. Specifically, the pH adjustment tank is connected to the sedimentation tank to receive the supernatant of the sedimentation tank.

[0026] Furthermore, the resin regeneration waste liquid treatment system also includes a clear water tank, the inlet end of the clear water tank is connected to the pH adjustment tank, and the outlet end of the clear water tank is connected to the outlet tank, and the clear water tank plays the role of collecting, storing and regulating water volume. The softened water treatment component as described above is connected to the outlet tank through a reflux pipe, or the reflux pipe passes through the clear water tank and then to the outlet tank. Exemplarily, the residence time of the liquid in the clear water tank is not less than 40 minutes.

[0027] Preferably, the resin regeneration waste liquid treatment system includes a sludge treatment component, and the sludge treatment component includes a sludge concentration tank and a dehydration unit connected by a pipeline. The sludge concentration tank is connected to the softened water treatment component through a pipeline, and is used to collect and treat the sludge of the softened water treatment component. For example, the sludge concentration tank can be connected to the coagulation tank, the flocculation tank, and the sedimentation tank through pipelines to receive the sludge, and the sludge concentration tank can perform sedimentation and concentration treatment on the sludge. The dehydration unit is used to receive the sludge transported from the sludge concentration tank and dehydrate the sludge to a water content of less than 60%, and transport it out for treatment regularly. The dehydration unit can use a filter press, for example.

[0028] The resin regeneration waste liquid treatment system includes a high-density tank, the water outlet of the high-density tank is connected to the water outlet tank through a pipeline, and the mud outlet of the high-density tank is connected to the sludge thickening tank through a pipeline. It can be understood that the sludge in the high-density tank is also transported to the sludge thickening tank for treatment.

[0029] Further, the filtration assembly includes a shallow sand filter, an ozone tower, an activated carbon filter and an ultrafiltration device which are sequentially connected in series through a pipeline, the ultrafiltration device is connected to the resin adsorption tower through a pipeline, and the shallow sand filter is connected to the water outlet of the water outlet pool through a pipeline. The shallow sand filter can remove suspended matter, the ozone tower and the activated carbon filter can degrade COD (chemical oxygen demand), and the ultrafiltration device is connected to the outlet end of the activated carbon filter for further filtration treatment.

[0030] Preferably, the resin regeneration waste liquid treatment system includes a regeneration liquid neutralization tank, which is connected to the resin adsorption tower through a pipeline, and the regeneration liquid neutralization tank is connected to the softening tank through a pipeline, and the regeneration liquid neutralization tank is located between the resin adsorption tower and the softening tank. The resin regeneration waste liquid treatment system includes a regeneration liquid collection tank, which is connected to the outlet end of the resin adsorption tower, and the regeneration liquid collection tank is connected to the inlet end of the regeneration liquid neutralization tank, and the regeneration liquid collection tank plays the role of collecting, storing and regulating water volume.

[0031] The resin regeneration waste liquid treatment system includes a backwash pipeline, and the resin adsorption tower and the filter assembly are connected to the high-density tank through the backwash pipeline to transport the backwash water to the high-density tank for treatment. For example, the shallow sand filter, the ozone tower, the activated carbon filter and the ultrafiltration device are all connected to the backwash pipeline.

[0032] The steps of resin regeneration include: backwashing → acid regeneration → acid replacement → alkali regeneration → alkali replacement. For example, the acid regeneration uses hydrochloric acid with a concentration of 31%, and the alkali regeneration uses sodium hydroxide with a concentration of 32%. The backwash water after backwashing the resin adsorption tower is transported to the high-density tank through the backwash pipeline for treatment, and the acid regeneration waste liquid, acid replacement liquid, alkali regeneration waste liquid, and alkali replacement waste liquid are all transported to the regeneration liquid collection tank. In this embodiment, the acid regeneration waste liquid, acid replacement liquid, alkali regeneration waste liquid, and alkali replacement waste liquid are collectively referred to as regeneration liquid.

[0033] Based on another aspect of the present invention, the present invention also provides a resin regeneration waste liquid treatment method, which is applied to the above resin regeneration waste liquid treatment system. The resin regeneration waste liquid treatment method includes step S1, step S2 and step S3. Step S1, step S2 and step S3 are described in detail below.

[0034] Step S1: The resin adsorption tower produces regeneration liquid.

[0035] Step S2: The regeneration liquid is sequentially passed into the softening water treatment component, the water outlet tank and the filtering component.

[0036] When the regeneration liquid is passed into the softening tank of the softening water treatment component, sodium carbonate and sodium hydroxide are added to the softening tank to remove hardness and adjust the pH value of the liquid in the softening tank to 11.3-12.0. For example, 8% sodium carbonate and 32% sodium hydroxide can be added to the softening tank.

[0037] Further, a coagulant (such as polyferric) is added to the coagulation tank to adsorb and precipitate impurities such as suspended matter, colloids and organic matter in the liquid in the coagulation tank. A flocculant (such as polyacrylamide with a molecular weight of 16 million) is added to the flocculation tank to further form large particles formed in the coagulation tank for precipitation and removal, and then the effluent of the flocculation tank enters the sedimentation tank, which plays a role in further settling the large particles formed in the flocculation tank. The supernatant of the sedimentation tank enters the pH adjustment tank, and the pH adjustment tank needs to add acid and alkali to neutralize the supernatant transported by the sedimentation tank to ensure that the pH value of the effluent of the pH adjustment tank is within the range of 6.0-9.0. Exemplarily, the residence time of the regenerated liquid in the softening tank of the softening water treatment component is not less than 20 minutes, the residence time in the coagulation tank is not less than 20 minutes, the residence time in the flocculation tank is not less than 20 minutes, the residence time in the sedimentation tank is not less than 150 minutes, and the residence time in the pH adjustment tank is not less than 20 minutes. In this embodiment, the inlet water hardness of the softening water treatment component is less than 3000 mg / L, the outlet water hardness is less than 150 mg / L, the residence time in the softening tank is set to 21.8 min, the residence time in the coagulation tank is set to 20.2 min, the residence time in the sedimentation tank is set to 2.8 h, and the residence time in the pH correction tank is set to 20.2 min.

[0038] In this embodiment, the inlet water quality of the softening water treatment component is: PH = 6-9, total hardness ≤ 3000 mg / L, suspended solids (SS) ≤ 200 mg / L; the outlet water quality of the softening water treatment component is: PH = 6-9, total hardness ≤ 150 mg / L, suspended solids (SS) ≤ 10 mg / L.

[0039] Step S3: The effluent from the filtration assembly is transported to a resin adsorption tower.

[0040] Thus, through the resin regeneration waste liquid treatment system and method of the present invention, the regeneration liquid generated during the resin regeneration process enters the regeneration liquid collection tank, and then enters the regeneration liquid neutralization tank for neutralization treatment. The neutralized liquid enters the softening water treatment component, passes through the softening tank, coagulation tank, flocculation tank, sedimentation tank, pH adjustment tank in sequence to remove suspended matter and total hardness and adjust pH before entering the clear water tank. The liquid in the clear water tank then enters the front-end outlet tank for recycling and reuse. Among them, the sludge generated in the softening water treatment component enters the sludge concentration tank for sedimentation and then enters the dehydration unit, reduces the sludge water content to less than 60% and then transports it for disposal.

[0041] As configured above, the present invention softens the resin regeneration liquid and adjusts the pH value through a softening water treatment component, thereby reducing the hardness of the resin regeneration liquid, reducing the impact of the resin regeneration liquid on the front-end process, reducing the operating load of the front-end process section, and making the effluent water quality of the front-end process section (the front-end process section in this embodiment is from the high-density tank to the water outlet tank to the filter component) stable and up to standard, avoiding frequent adsorption saturation of the resin, and reducing the amount of reagents added in the front-end process section. In summary, the present invention avoids frequent adjustments to the amount of reagents added, reduces the control requirements for the amount of reagents added in the front-end process, simplifies the operation of the water treatment system, and has the advantages of stable operation effect, reduced system impact, and reduced operating costs.

[0042] It should be noted that references to "one embodiment", "an embodiment", "a specific embodiment", "some embodiments", etc. in the specification only indicate that the described embodiment may include a particular feature, structure or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. In addition, when a particular feature, structure or characteristic is described in conjunction with an embodiment, whether or not explicitly described, it is within the knowledge of a person skilled in the relevant art to implement such feature, structure or characteristic in conjunction with other embodiments.

[0043] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.

[0044] It should also be noted that, although the present invention has been disclosed as a preferred embodiment, the above embodiment is not intended to limit the present invention. For any technician familiar with the art, without departing from the scope of the technical solution of the present invention, the technical content disclosed above can be used to make many possible changes and modifications to the technical solution of the present invention, or modified into equivalent embodiments of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

[0045] It should also be understood that, unless otherwise specified or indicated, the terms "first", "second", "third", etc. in the specification are merely used to distinguish between the various components, elements, steps, etc. in the specification, and are not used to indicate the logical relationship or sequential relationship between the various components, elements, steps, etc.

[0046] It should also be recognized that the terms described herein are only used to describe specific embodiments and are not intended to limit the scope of the invention. It should be noted that the singular forms "a" and "an" used herein and in the appended claims include plural references unless the context clearly indicates otherwise. For example, a reference to "a step" or "a device" means a reference to one or more steps or devices, and may include secondary steps and secondary devices. All conjunctions used should be understood in the broadest sense. And, the word "or" should be understood to have the definition of a logical "or", rather than a logical "exclusive or", unless the context clearly indicates otherwise. In addition, the implementation of the method and / or device in the embodiments of the present invention may include performing the selected task manually, automatically, or in combination.

Claims

1. A resin regeneration waste liquid treatment system, characterized in that: include: The water outlet tank, the filtering component, the resin adsorption tower and the softened water treatment component are connected in series through pipelines. The softened water treatment component is connected to the water outlet tank through a reflux pipe. The softened water treatment component includes a softening tank and a coagulation and flocculation unit connected in series through pipelines.

2. The resin regeneration waste liquid treatment system according to claim 1, characterized in that: The coagulation and flocculation unit comprises a coagulation tank, a flocculation tank and a sedimentation tank which are sequentially connected in series through pipelines.

3. The resin regeneration waste liquid treatment system according to claim 1, characterized in that: The softened water treatment component comprises a sodium carbonate dosing component and a sodium hydroxide dosing component. The dosing port of the sodium carbonate dosing component leads to the softening tank, and the dosing port of the sodium hydroxide dosing component leads to the softening tank.

4. The resin regeneration waste liquid treatment system according to claim 1, characterized in that: The softened water treatment component comprises a pH adjustment tank, which is connected to the coagulation and flocculation unit and is located in the downstream direction of the coagulation and flocculation unit.

5. The resin regeneration waste liquid treatment system according to claim 1, characterized in that: The resin regeneration waste liquid treatment system includes a sludge treatment component, which includes a sludge concentration tank and a dehydration unit connected by a pipeline. The sludge concentration tank is connected to the softened water treatment component through a pipeline and is used to collect and treat the sludge of the softened water treatment component.

6. The resin regeneration waste liquid treatment system according to claim 5, characterized in that: The resin regeneration waste liquid treatment system comprises a high-density tank, the water outlet of the high-density tank is connected to the water outlet tank through a pipeline, and the mud outlet of the high-density tank is connected to the sludge concentration tank through a pipeline.

7. The resin regeneration waste liquid treatment system according to claim 1, characterized in that: The filtering assembly comprises a shallow sand filter, an ozone tower, an activated carbon filter and an ultrafiltration device which are sequentially connected in series through pipelines, and the ultrafiltration device is connected with the resin adsorption tower through a pipeline.

8. The resin regeneration waste liquid treatment system according to claim 1, characterized in that: The resin regeneration waste liquid treatment system includes a regeneration liquid neutralization tank, which is connected to the resin adsorption tower through a pipeline, and the regeneration liquid neutralization tank is connected to the softening tank through a pipeline, and the regeneration liquid neutralization tank is located between the resin adsorption tower and the softening tank.

9. A resin regeneration waste liquid treatment method, applied to the resin regeneration waste liquid treatment system according to any one of claims 1 to 8, characterized in that: include: The resin adsorption tower produces regeneration liquid; The regeneration liquid is sequentially passed into the softening water treatment component, the water outlet tank and the filter component; The effluent from the filtration assembly is transported to the resin adsorption tower; When the regeneration liquid is passed into the softening tank of the softening water treatment component, sodium carbonate and sodium hydroxide are added into the softening tank to remove hardness and adjust the pH value of the liquid in the softening tank to 11.3-12.

0.

10. The resin regeneration waste liquid treatment method according to claim 9, characterized in that: The pH value of the effluent from the softening water treatment component is adjusted to 6.0-9.0.

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