Desulfurization Wastewater Pretreatment Method and System

Abstract

This application relates to the field of industrial wastewater treatment, and specifically relates to a desulfurization wastewater pretreatment method and system. This pretreatment method is applicable before atomizing the desulfurization wastewater. The pretreatment method includes the following steps: obtaining the scaling components in the desulfurization wastewater; selecting a scale inhibitor according to the scaling components; calculating the supersaturation ratio after concentrating the desulfurization wastewater; obtaining the ion concentration of the scaling components in the desulfurization wastewater and the effective component concentration in the scale inhibitor; calculating the mixing ratio of the scale inhibitor and the desulfurization wastewater based on the supersaturation ratio, the ion concentration of the scaling components, and the effective component concentration in the scale inhibitor; uniformly mixing the scale inhibitor and the desulfurization wastewater according to the mixing ratio. In the method provided by the present invention, before atomizing the desulfurization wastewater, by adding a suitable scale inhibitor to the desulfurization wastewater, the problem of pipeline scale blockage can be effectively avoided at a relatively low cost, ensuring the normal operation of the equipment.

Description

Technical Field

[0001] This application relates to the field of industrial wastewater treatment, and specifically relates to a desulfurization wastewater pretreatment method and a desulfurization wastewater pretreatment system. Background Art

[0002] In China, the requirements for industrial water use and wastewater discharge are becoming increasingly strict. Thermal power plants have started to deeply optimize the water use of the whole plant, and zero-discharge transformation of wastewater has been implemented. For the zero-discharge process of wastewater, there are two flue gas evaporation processes: direct injection and post-concentration injection. During the direct injection process, the evaporation of wastewater is large and the energy consumption is high; the concentrated evaporation process can reduce the evaporation of wastewater and lower the energy consumption, but the concentration leads to a sharp increase in the salt content of the wastewater, which easily causes serious pipeline scaling and blockage problems. At present, to address the pipeline blockage problem, pre-desalination by adding chemicals or membrane methods are mainly used. Adding chemicals will generate a large amount of sludge, increasing the later treatment cost; the membrane treatment method has high operation and investment costs, and there are also problems such as membrane fouling. Therefore, there is an urgent need for a wastewater treatment method with high cost performance and good scale inhibition effect to meet industrial needs. Summary of the Invention

[0003] The purpose of the embodiments of this application is to provide a desulfurization wastewater pretreatment method and system to reduce the cost of wastewater treatment and ensure the stable operation of equipment.

[0004] To achieve the above purpose, in the first aspect of this application, a desulfurization wastewater pretreatment method is provided. This pretreatment method is applicable before atomizing the desulfurization wastewater. The pretreatment method includes the following steps: obtaining the scaling components in the desulfurization wastewater; selecting a scale inhibitor according to the scaling components; calculating the supersaturation ratio after concentrating the desulfurization wastewater; obtaining the ion concentration of the scaling components in the desulfurization wastewater and the effective component concentration in the scale inhibitor; calculating the mixing ratio of the scale inhibitor and the desulfurization wastewater based on the supersaturation ratio, the ion concentration of the scaling components, and the effective component concentration in the scale inhibitor; and uniformly mixing the scale inhibitor and the desulfurization wastewater according to the mixing ratio.

[0005] Based on the first aspect, in some embodiments of the present invention, the scaling components include CaSO4. The calculation of the supersaturation ratio after concentrating the desulfurization wastewater includes: calculating the supersaturation ratio of the desulfurization wastewater before concentration; after concentration treatment, obtaining the concentration ratio, and calculating the supersaturation ratio of the desulfurized wastewater after concentration based on the concentration ratio and the supersaturation ratio of the desulfurization wastewater before concentration.

[0006] Based on the first aspect, in some embodiments of the present invention, the formula for calculating the supersaturation ratio S of the desulfurization wastewater before concentration is as follows:

[0007]

[0008] In formula (1), and are respectively Ca2+ and ion activity of k SP is the solubility product constant of CaSO4.

[0009] Based on the first aspect, in some embodiments of the present invention, the supersaturation ratio S after concentration of the desulfurized wastewater x is calculated by the following formula:

[0010] S x = S·k1X (2)

[0011] In formula (2), X is the concentration ratio, and k1 is the correction coefficient.

[0012] Based on the first aspect, in some embodiments of the present invention, the mixing ratio is a volume mixing ratio, and uniformly mixing the scale inhibitor with the desulfurized wastewater according to the mixing ratio includes: obtaining the volume of the desulfurized wastewater; calculating the volume of the scale inhibitor according to the volume of the desulfurized wastewater and the volume mixing ratio.

[0013] Based on the first aspect, in some embodiments of the present invention, obtaining the volume of the desulfurized wastewater includes: obtaining the bottom area A of the vessel for containing the desulfurized wastewater 底面积 ; obtaining the liquid level height h of the desulfurized wastewater in the vessel; if the vessel for containing the desulfurized wastewater is a cuboid, the volume calculation formula of the desulfurized wastewater is as follows: V 废水 = h*A 底面积 (4).

[0014] Based on the first aspect, in some embodiments of the present invention, the volume V of the scale inhibitor with an active ingredient concentration of c is calculated according to the following formula 阻垢剂 : 阻垢剂 :

[0015]

[0016] In formula (5), is the concentration of Ca 2+ in the desulfurized wastewater, is the concentration of in the desulfurized wastewater, is the concentration of Mg 2+ in the desulfurized wastewater.

[0017] Based on the first aspect, in some embodiments of the present invention, before adding the scale inhibitor to the desulfurized wastewater and during the process of adding the scale inhibitor, the pH value of the desulfurized wastewater or the mixed solution is controlled to always remain within a preset range.

[0018] Second aspect, the present application provides a desulfurized wastewater pretreatment system. Before atomizing the desulfurized wastewater, the desulfurized wastewater is pretreated by this treatment system. The pretreatment system includes: a first acquisition module for acquiring the scaling components in the desulfurized wastewater; a selection module for selecting a scale inhibitor according to the scaling components; a first calculation module for calculating the supersaturation ratio after concentration of the desulfurized wastewater; a second acquisition module for acquiring the ion concentration of the scaling components in the desulfurized wastewater and the effective component concentration in the scale inhibitor; a second calculation module for calculating the mixing ratio of the scale inhibitor and the desulfurized wastewater based on the supersaturation ratio, the ion concentration of the scaling components, and the effective component concentration in the scale inhibitor; and a mixing module for uniformly mixing the scale inhibitor and the desulfurized wastewater according to the mixing ratio.

[0019] Based on the second aspect, in some embodiments of the present invention, the mixing module includes: a wastewater storage tank, a scale inhibitor storage tank, and a pump one for feeding the scale inhibitor in the scale inhibitor storage tank into the wastewater storage tank for mixing; the pretreatment system further includes: a liquid level measuring device for measuring the liquid level height of the desulfurized wastewater in the wastewater storage tank; a PH detection device for measuring the PH value of the liquid in the wastewater storage tank; a PH adjustment liquid tank for containing a PH adjustment liquid, and the PH adjustment liquid is used to adjust the PH value of the desulfurized wastewater in the wastewater storage tank; a pump two for feeding the PH adjustment liquid into the wastewater storage tank; a controller for acquiring the liquid level height feedback by the liquid level measuring device and controlling the pump one to feed a first specific amount of the scale inhibitor into the wastewater storage tank based on the liquid level height; and for acquiring the PH value feedback by the PH detection device and controlling the pump two to feed a second specific amount of the PH adjustment liquid into the wastewater storage tank based on the PH value.

[0020] The present invention has at least the following beneficial effects:

[0021] 1) Before atomizing the desulfurized wastewater, by adding a suitable scale inhibitor to the desulfurized wastewater, scaling and crystallization in the pipeline from the outlet of the wastewater storage tank to the inlet of the atomizing device can be avoided at a relatively low cost, effectively avoiding the problem of pipeline scale blockage and ensuring the normal operation of the equipment.

[0022] 2) By strictly controlling the addition amount of the scale inhibitor, the purpose of cost saving can be achieved.

[0023] 3) By strictly controlling the PH value of the solution in the wastewater storage tank, the activity of the scale inhibitor can be maintained.

[0024] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific implementation part. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the embodiments of the present application, and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation to the embodiments of the present application. In the accompanying drawings:

[0026] Figure 1 Schematically shows a flowchart of the desulfurized wastewater pretreatment method according to an embodiment of the present application;

[0027] Figure 2 Schematically shows a partial structural diagram of the desulfurized wastewater pretreatment system according to an embodiment of the present application;

[0028] Figure 3 Schematically shows a process flowchart of the direct injection wastewater evaporation process according to an embodiment of the present application;

[0029] Figure 4 Schematically shows a process flowchart of the concentrated injection wastewater evaporation process according to an embodiment of the present application.

[0030] Explanation of reference numerals

[0031] 1 - Wastewater storage tank; 2 - Scale inhibitor storage tank; 3 - Pump 1; 4 - Liquid level measuring device; 5 - pH detection device; 6 - pH adjustment liquid tank; 7 - Pump 2; 8 - Pump 3. Specific embodiments

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. It should be understood that the specific embodiments described herein are only used to illustrate and explain the embodiments of the present application, and do not limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0033] It should be noted that if there are directional indications (such as up, down, left, right, front, back, etc.) involved in the embodiments of the present application, then such directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If this specific posture changes, then such directional indications will also change accordingly.

[0034] In addition, if the embodiments of the present application involve descriptions such as "first", "second", etc., the descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present application.

[0035] Embodiment 1

[0036] Please refer to Figure 1 , this embodiment provides a method for pretreatment of desulfurized wastewater, which is applicable before atomizing the desulfurized wastewater. The pretreatment method includes the following steps:

[0037] S1. Obtain the scaling components in the desulfurized wastewater;

[0038] Before selecting a scale inhibitor, it is necessary to first determine the main scaling components during the transportation of the desulfurized wastewater in order to "prescribe the right medicine". Specifically, the main scaling components during the transportation of the desulfurized wastewater are mainly CaSO4 and MgCl2.

[0039] S2. Select a scale inhibitor according to the scaling components;

[0040] Specifically, for the desulfurized wastewater with the main scaling component being CaSO4, the scale inhibitor can be selected as follows: 1) The low-phosphorus corrosion and scale inhibitor HEDP achieves the scale inhibition effect through chelation solubilization effect, lattice distortion effect and the same-sex repulsion after oxygen ion adsorption; 2) The scale inhibition mechanisms of organic phosphonate scale inhibitors (such as ATMP, EDTMP, etc.), scale inhibitors containing multiple carboxylic acid groups (such as citric acid) and polymer scale inhibitors (such as polyacrylic acid, polymaleic acid, etc.) are mainly adsorption mechanisms, that is, they preferentially adsorb on the active growth points of certain specific crystal planes and block the further growth of crystals; 3) The anionic scale inhibitor polyepoxysuccinic acid (PESA) achieves the scale inhibition effect through chelation solubilization effect and lattice distortion effect.

[0041] S3. Calculate the supersaturation ratio after concentration of the desulfurized wastewater; this step can be divided into the following two steps:

[0042] S301. Calculate the supersaturation ratio of the desulfurized wastewater before concentration;

[0043]

[0044] In formula (1): and are respectively Ca2+ and ion activity. Specifically, where k SP is the solubility product constant of CaSO4; are the concentrations of Ca 2+ and in the desulfurized wastewater, respectively; and are the activity coefficients of Ca 2+ , respectively; the activity coefficients of calcium ions and sulfate ions are the same, and their calculation formula is as follows:

[0045]

[0046] In formula (1-3), m i is the molality of the i-th Ca 2+ or , z i is the valence of the i-th Ca 2+ or , and A is a constant at a fixed temperature.

[0047] After S302 and concentration treatment, the concentration ratio is obtained, and the supersaturation ratio of the desulfurized wastewater after concentration is calculated based on the concentration ratio and the supersaturation ratio of the desulfurized wastewater before concentration.

[0048] The supersaturation ratio S x of the desulfurized wastewater after concentration is calculated as follows:

[0049] S x = S·k1X (2)

[0050] In formula (2), X is the concentration ratio, and k1 is the correction coefficient.

[0051] Exemplarily, the concentration ratio X usually takes values of 2, 4, 6, 8. When X = 1, the wastewater is not concentrated. The value range of the supersaturation ratio S (before concentration) is 1.2 - 20. The increase in the concentration ratio will lead to an increase in the salts in the wastewater, thereby causing an increase in the supersaturation ratio S x and the concentration of the scale inhibitor also needs to be increased accordingly.

[0052] S4. Obtain the ionic concentrations of the scaling components in the desulfurized wastewater and the concentration of the active ingredient in the scale inhibitor;

[0053] Regarding the concentration of the active ingredient in the scale inhibitor (hereinafter referred to as the scale inhibitor concentration), when S x is 1.2 - 5, the added scale inhibitor concentration is 10 - 20 ml / L; when S x is 5 - 20, the added scale inhibitor concentration is 20 - 30 ml / L.

[0054] The ionic concentrations of the scaling components in the desulfurized wastewater include and i.e., the concentration of Ca 2+ , the concentration of , the concentration of Cl - , and the concentration of Mg 2+ . The above concentration data can be obtained through a concentration detection device.

[0055] S5. Calculate the mixing ratio of the scale inhibitor and the desulfurized wastewater based on the supersaturation ratio, the ionic concentrations of the scaling components, and the concentration of the active ingredient in the scale inhibitor; specifically, the volume mixing ratio of the scale inhibitor and the desulfurized wastewater can be expressed by the following formula:

[0056]

[0057] S6. Uniformly mix the scale inhibitor and the desulfurized wastewater according to the mixing ratio. Specifically, the mixing ratio in this embodiment mainly refers to the volume mixing ratio.

[0058] S601. Obtain the volume of the desulfurized wastewater, which specifically includes the following steps:

[0059] A1. Obtain the bottom area A of the vessel for containing the desulfurized wastewater 底面积 ;

[0060] A2. Obtain the liquid level height h of the desulfurized wastewater in the vessel;

[0061] If the vessel for containing the desulfurized wastewater is a cuboid, the volume calculation formula of the desulfurized wastewater is as follows:

[0062] V 废水 = h * A 底面积 (4).

[0063] S602. Calculate the volume of the scale inhibitor according to the volume of the desulfurized wastewater and the volume mixing ratio. The volume V 阻垢剂 of the scale inhibitor with an active ingredient concentration of c 阻垢剂 is calculated as follows:

[0064]

[0065] In formula (5), is the concentration of Ca 2+ in the desulfurized wastewater, is the concentration of in the desulfurized wastewater, is the concentration of Mg 2+ in the desulfurized wastewater.

[0066] Preferably, in this embodiment, before adding the scale inhibitor to the desulfurized wastewater and during the process of adding the scale inhibitor, the pH value of the desulfurized wastewater or the mixed solution (referring to the mixed solution of the desulfurized wastewater and the scale inhibitor) is controlled to always remain within a preset range value. The preset range value is 4-6 to ensure that the scale inhibitor does not lose its activity. The pH adjustment liquid used to control the pH value of the desulfurized wastewater or the mixed solution can be dilute hydrochloric acid or nitric acid.

[0067] Example 2

[0068] This embodiment provides a desulfurized wastewater pretreatment system. Before atomizing the desulfurized wastewater, the desulfurized wastewater is pretreated through this treatment system. The pretreatment system includes:

[0069] The first acquisition module is used to acquire the scaling components in the desulfurized wastewater;

[0070] The selection module is used to select a scale inhibitor according to the scaling components;

[0071] The first calculation module is used to calculate the supersaturation ratio after concentration of the desulfurized wastewater;

[0072] The second acquisition module is used to acquire the ion concentration of the scaling components in the desulfurized wastewater and the concentration of the active ingredients in the scale inhibitor;

[0073] The second calculation module is used to calculate the mixing ratio of the scale inhibitor and the desulfurized wastewater based on the supersaturation ratio, the ion concentration of the scaling components, and the concentration of the active ingredients in the scale inhibitor;

[0074] The mixing module is used to uniformly mix the scale inhibitor and the desulfurized wastewater according to the mixing ratio.

[0075] Specifically, as Figure 2 shown, the mixing module includes: a wastewater storage tank 1, a scale inhibitor storage tank 2, and a pump 3 for feeding the scale inhibitor in the scale inhibitor storage tank 2 into the wastewater storage tank 1 for mixing;

[0076] The pretreatment system further includes:

[0077] A liquid level measuring device 4 for measuring the liquid level height of the desulfurized wastewater in the wastewater storage tank 1;

[0078] A pH detection device 5 for measuring the pH value of the liquid in the wastewater storage tank 1;

[0079] A pH adjustment liquid tank 6 for containing the pH adjustment liquid, and the pH adjustment liquid is used to adjust the pH value of the desulfurized wastewater in the wastewater storage tank 1;

[0080] A pump 7 for feeding the pH adjustment liquid into the wastewater storage tank 1;

[0081] A controller is used to obtain the liquid level height feedback by the liquid level measuring device 4 and control the first pump 3 to feed a first specific amount of scale inhibitor into the waste water storage tank 1 based on the liquid level height; and is used to obtain the pH value feedback by the pH detection device 5 and control the second pump 7 to feed a second specific amount of pH adjustment liquid into the waste water storage tank 1 based on the pH value. Among them, the calculation process of the first specific amount can refer to S3 - S6 in Embodiment 1. This will not be elaborated here.

[0082] Among them, the calculation of the second specific amount (volume) needs to be calculated based on data such as the solution volume in the waste water storage tank 1, the concentration of each acid and base ion in the solution, the type and concentration of the pH adjustment liquid, and the pH value feedback by the pH detection device 5. Additionally, a simpler way is to adjust the operating state of the first pump 3 based on the data real-time feedback by the pH detection device 5, that is, when the pH value feedback by the pH detection device 5 is within the preset range value (referring to the concept of the preset range value in Embodiment 1), the second pump 7 is not started; when the pH value feedback by the pH detection device 5 is not within the preset range value (usually greater than the upper limit 6 of the preset range value), the second pump 7 is started.

[0083] Furthermore, the pretreatment system further includes a third pump 8, which is used to suck out the desulfurized waste water mixed with scale inhibitor from the waste water storage tank 1 and send it to the subsequent treatment unit. Similarly, the third pump 8 is connected to the controller and responds to the liquid level height value feedback by the liquid level measuring device 4. For example, when the liquid level height of the desulfurized waste water in the waste water storage tank 1 reaches 90% of the height of the waste water storage tank 1, the third pump 8 is started to suck out the desulfurized waste water and send it to the subsequent treatment unit.

[0084] Embodiment 3

[0085] For the desulfurized waste water after mixing with the scale inhibitor, the subsequent treatment unit is as follows Figure 3 shown. Before the flue gas enters the air preheater, high-temperature flue gas above 310°C is introduced from the boiler and enters the bypass evaporation tower device. The waste water is transported from the waste water storage tank 1 to the atomizing device at the top of the evaporation tower by a circulation pump (the third pump 8), and after passing through the atomizing device, the waste water is sprayed into the evaporation device, and is evaporated and crystallized by the high-temperature flue gas. The flue gas after being treated by the evaporation device enters the main flue electrostatic precipitator through the bypass flue induced draft fan, and then the waste water crystallization salts are removed by the electrostatic precipitator. In the whole process, the part that is prone to pipeline blockage is the pipeline from the outlet of the waste water storage tank 1 to the inlet of the atomizing device. This patent adds a certain amount of scale inhibitor, which can effectively delay the crystallization induction time during transportation and avoid the problem of scale formation and pipeline blockage in the pipeline. This process is the direct injection process used in the waste water evaporation process.

[0086] Embodiment 4

[0087] For the desulfurized waste water after mixing with the scale inhibitor, the subsequent treatment unit is as follows Figure 4As shown. Similarly, before the flue gas enters the air preheater, high-temperature flue gas above 310°C is introduced from the boiler and enters the bypass evaporation tower device. The wastewater is transported from the wastewater storage tank 1 by a circulation pump. First, it passes through the concentration device. The concentration device has methods such as waste heat and membrane treatment, and the concentration ratio can be controlled at about 5. The concentrated wastewater is then transported to the evaporation tower device for evaporation treatment. Due to the concentration treatment, the introduction amount of high-temperature flue gas can be significantly reduced, improving the overall thermal efficiency of the unit. In the whole process, the parts prone to pipeline blockage are the pipeline from the outlet of the wastewater storage tank 1 to the inlet of the atomization device, and the inside of the concentration device. In this patent, a certain amount of scale inhibitor is added, which can effectively delay the crystallization induction time during transportation and avoid the problem of scale blockage. This process is the concentration injection process used in the wastewater evaporation process.

[0088] Figure 1 It is a schematic flow chart of the desulfurization wastewater pretreatment method in an embodiment. It should be understood that although Figure 1 each step in the flow chart is shown in sequence according to the arrow indication, these steps are not necessarily executed in the order indicated by the arrow. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, Figure 1 at least a part of the steps in

[0089] may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential either, but can be executed alternately or in turn with at least a part of other steps or sub-steps or stages of other steps.

[0090] The above are only the embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A method for pretreatment of desulfurized wastewater, characterized in that, This pretreatment method is applicable before atomizing the desulfurized wastewater, and the pretreatment method includes the following steps: Obtain the scaling components in the desulfurized wastewater; Select a scale inhibitor according to the scaling components; Calculate the supersaturation ratio of the concentrated desulfurized wastewater according to the scaling components; Obtain the ion concentration of the scaling components in the desulfurized wastewater and the effective component concentration in the scale inhibitor; Based on the supersaturation ratio, the ion concentration of the scaling components, and the effective component concentration in the scale inhibitor, calculate the volume mixing ratio of the scale inhibitor to the desulfurized wastewater. The volume mixing ratio of the scale inhibitor to the desulfurized wastewater can be obtained through the following formula: Among them, V 阻垢剂 is the volume of the scale inhibitor, V 废水 is the volume of the desulfurized wastewater, S x is the supersaturation ratio after concentration of the desulfurized wastewater, is the concentration of Ca 2+ in the desulfurized wastewater, is the concentration of in the desulfurized wastewater, is the concentration of Cl - in the desulfurized wastewater, is the concentration of Mg 2+ in the desulfurized wastewater, c 阻垢剂 is the concentration of the active ingredient in the scale inhibitor; Uniformly mix the scale inhibitor and the desulfurized wastewater according to the volume mixing ratio.

2. The desulfurized wastewater pretreatment method according to claim 1, wherein, The scaling components include CaSO4. The calculation of the supersaturation ratio of the concentrated desulfurized wastewater according to the scaling components includes: Calculate the supersaturation ratio of the desulfurized wastewater before concentration; After concentration treatment, obtain the concentration multiple, and calculate the supersaturation ratio of the concentrated desulfurized wastewater based on the concentration multiple and the supersaturation ratio of the desulfurized wastewater before concentration.

3. The desulfurized wastewater pretreatment method according to claim 2, wherein The calculation formula for the supersaturation ratio S of the desulfurized wastewater before concentration is as follows: In formula (1), and are the ionic activities of Ca 2+ and respectively, and k SP is the solubility product constant of CaSO4.

4. The desulfurized wastewater pretreatment method according to claim 3, characterized in that, The supersaturation ratio S after concentration of the desulfurized wastewater x is calculated as follows: S x = S·k1X (2) In formula (2), S is the supersaturation ratio of the desulfurized wastewater before concentration, X is the concentration multiple, and k1 is the correction coefficient.

5. The desulfurized wastewater pretreatment method according to claim 4, characterized in that, The step of uniformly mixing the scale inhibitor and the desulfurized wastewater according to the volume mixing ratio includes: Obtain the volume of the desulfurized wastewater; Calculate the volume of the scale inhibitor according to the volume of the desulfurized wastewater and the volume mixing ratio.

6. The desulfurized wastewater pretreatment method according to claim 5, wherein, The obtaining of the volume of the desulfurized wastewater includes: Obtain the bottom area A of the container for holding the desulfurized wastewater 底面积 ; Obtain the liquid level height h of the desulfurized wastewater in the container; If the container for holding the desulfurized wastewater is a cuboid, the calculation formula for the volume of the desulfurized wastewater is as follows: V 废水 = h * A 底面积 (4).

7. The desulfurized wastewater pretreatment method according to claim 5, wherein Calculate the volume V of the scale inhibitor with an active ingredient concentration of c according to the following formula 阻垢剂 as follows 阻垢剂 :[[]]END]] In formula (5), V 阻垢剂 is the volume of the scale inhibitor, S x is the supersaturation ratio after concentration of the desulfurization wastewater, V 废水 is the volume of the desulfurization wastewater, is the concentration of Ca 2+ in the desulfurization wastewater, is the concentration of in the desulfurization wastewater, is the concentration of Cl - in the desulfurization wastewater, is the concentration of Mg 2+ in the desulfurization wastewater, c 阻垢剂 is the concentration of the active ingredient in the scale inhibitor.

8. The desulfurized wastewater pretreatment method according to claim 1, wherein Before adding the scale inhibitor to the desulfurized wastewater and during the addition process of the scale inhibitor, control the pH value of the desulfurized wastewater or the mixed solution to always remain within the preset range.

9. A desulfurized wastewater pretreatment system, applied to the desulfurized wastewater pretreatment method described in any one of claims 1-8, characterized in that, Before atomizing the desulfurized wastewater, perform desulfurized wastewater pretreatment through this pretreatment system. The pretreatment system includes: A first acquisition module for obtaining the scaling components in the desulfurized wastewater; A selection module for selecting a scale inhibitor according to the scaling components; A first calculation module for calculating the supersaturation ratio of the concentrated desulfurized wastewater according to the scaling components; A second acquisition module for obtaining the ion concentration of the scaling components in the desulfurized wastewater and the effective component concentration in the scale inhibitor; A second calculation module for calculating the volume mixing ratio of the scale inhibitor to the desulfurized wastewater based on the supersaturation ratio, the ion concentration of the scaling components, and the effective component concentration in the scale inhibitor. The volume mixing ratio of the scale inhibitor to the desulfurized wastewater can be obtained through the following formula: Among them, V 阻垢剂 is the volume of the scale inhibitor, V 废水 is the volume of the desulfurized wastewater, S x is the supersaturation ratio after concentration of the desulfurized wastewater, is the concentration of Ca 2+ in the desulfurized wastewater, is in the desulfurized wastewater concentration, is the concentration of Cl - in the desulfurized wastewater, is the concentration of Mg 2+ in the desulfurized wastewater, c 阻垢剂 is the concentration of the active ingredient in the scale inhibitor; A mixing module for uniformly mixing the scale inhibitor and the desulfurized wastewater according to the volume mixing ratio.

10. The desulfurized wastewater pretreatment system according to claim 9, wherein The mixing module includes: a wastewater storage tank, a scale inhibitor storage tank, and a pump 1 for feeding the scale inhibitor in the scale inhibitor storage tank into the wastewater storage tank for mixing; The pretreatment system further includes: A liquid level measuring device for measuring the liquid level height of the desulfurized wastewater in the wastewater storage tank; A pH detection device for measuring the pH value of the liquid in the wastewater storage tank; A pH adjustment liquid pool for containing a pH adjustment liquid, which is used to adjust the pH value of the desulfurization wastewater in the wastewater storage tank; A second pump for sending the pH adjustment liquid into the wastewater storage tank; A controller for obtaining the liquid level height fed back by the liquid level measuring device and controlling the first pump to send a first specific amount of scale inhibitor into the wastewater storage tank based on the liquid level height; and for obtaining the pH value fed back by the pH detection device and controlling the second pump to send a second specific amount of pH adjustment liquid into the wastewater storage tank based on the pH value.

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