Desulfurization wastewater desilting method and system

Abstract

The invention relates to the technical field of desulfurization wastewater treatment, in particular to a desulfurization wastewater desilting method and system.The desulfurization wastewater desilting method comprises the steps that chemicals are added into desulfurization wastewater, and the desulfurization wastewater added with the chemicals enters an industrial wastewater pool for solid matter static precipitation; carrying out discharge treatment on the wastewater after the solid matters are precipitated to a preset liquid level, and stopping the treatment; performing pneumatic automatic stirring and automatic discharging on solid matters in the industrial wastewater pool through aeration; and discharging the stirred mud-water mixture to a desulfurization wastewater pre-sedimentation tank for sedimentation. The device and the method have the beneficial effects that the removal efficiency of solid matters in the desulfurization wastewater is effectively improved, the manual cleaning cost and time are reduced, the problems of water quality deterioration and membrane system blockage are avoided, the continuity and stability of wastewater treatment are ensured, environmental protection and resource recovery are facilitated, and in addition, the device and the method have good application prospects. According to the invention, the wastewater recycling standard can be reached only through one-time dosing, the treatment efficiency is improved, the use of chemicals is reduced, and the potential pollution to the environment is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of desulfurization wastewater treatment, in particular to a method and system for desludge removal from desulfurization wastewater. Background Art

[0002] At present, coal-fired power plants generally use the traditional three-tank process to treat desulfurization wastewater. The desulfurization wastewater three-tank includes a neutralization tank, a sedimentation tank, and a flocculation tank. The pH adjustment tank (neutralization tank) of the desulfurization wastewater treatment system, adds lime milk slurry in the pH adjustment tank (neutralization tank), adjusts the pH value to 9-10, and fluoride ions and some heavy metal ions form insoluble substances and enter the reaction tank. In the reaction tank, organic sulfides are added, and all heavy metal ions form insoluble substances and enter the flocculation tank. Flocculants and coagulants are added to the flocculation tank to make the insoluble substances formed previously condense into large alum flowers and enter the clarification tank. In the clarification tank, the solid precipitate is separated from the clean water. The clean water of the desulfurization wastewater enters the desulfurization wastewater comprehensive treatment system, but the desulfurization wastewater cannot be completely precipitated in the clarification tank. The clean water of wastewater contains a large amount of suspended solids, which can only precipitate 40-60% of macromolecular solids such as calcium sulfate and calcium carbonate, and only 10-20% of lightweight magnesium hydroxide. The unprecipitated magnesium hydroxide, calcium carbonate and calcium sulfate will be precipitated in the #2 / 3 / 4 industrial wastewater pool. The sediment in the #2 / 3 / 4 industrial wastewater pool will quickly reach the water pump suction port. At present, the #2 / 3 / 4 industrial wastewater pool is treated with membrane treatment. If the #2 / 3 / 4 industrial wastewater pool is not cleaned in time, the water quality of the desulfurization wastewater will be seriously deteriorated, and eventually the membrane system will be blocked or even the membrane will be completely scrapped. Summary of the invention

[0003] In view of the above problems or problems existing in the prior art, the present invention is proposed.

[0004] Therefore, the purpose of the present invention is to provide a method for desludging desulfurization wastewater, which can solve the problem that the desulfurization wastewater pre-sedimentation tank cannot precipitate all solids, resulting in excessively high suspended solids content in the wastewater, affecting the operating efficiency and water quality of the subsequent membrane treatment system.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for removing mud from desulfurized wastewater, which comprises adding a drug to the desulfurized wastewater, so that the desulfurized wastewater after adding the drug enters an industrial wastewater pool for solid matter to settle;

[0006] The wastewater after solid precipitation is discharged to the preset liquid level and the treatment is stopped;

[0007] Automatically pneumatically stir and discharge solids in industrial wastewater pools through aeration;

[0008] The stirred mud-water mixture is discharged into the desulfurization wastewater pre-sedimentation tank for sedimentation.

[0009] As a preferred embodiment of the method for removing mud from desulfurized wastewater of the present invention, the industrial wastewater pool includes three industrial wastewater pools; when the desulfurized wastewater after adding chemicals is discharged into the industrial wastewater pool, the discharge is automatically stopped when the liquid level rises to a preset height.

[0010] As a preferred solution of the method for desludging desulfurization wastewater of the present invention, the discharge treatment includes desulfurization wastewater membrane treatment technology, and the wastewater after solid sedimentation is discharged through membrane treatment, and the discharge is automatically stopped when the liquid level drops to a preset height.

[0011] As a preferred embodiment of the method for removing mud from desulfurization wastewater of the present invention, aeration includes passing compressed air into an aeration port, pneumatically stirring the remaining solid matter and wastewater at the aeration port to achieve mud and water stirring.

[0012] As a preferred embodiment of the method for desludging desulfurization wastewater of the present invention, the operation line from the industrial wastewater pool to the wastewater pre-sedimentation pool is operated intermittently at a fixed time, and the intermittent time includes the time required for the desulfurization wastewater to be discharged into or discharged to a preset water level, and the static sedimentation time.

[0013] In order to solve the above-mentioned technical problems, the present invention also provides the following technical solutions: a desulphurization wastewater desludging system, comprising a desludging unit, including a dosing module, a sedimentation module connected to the dosing module, a clean water recovery module connected to the sedimentation module, a clean water storage module connected to the clean water recovery module, and a clean water discharge module connected to the clean water storage module.

[0014] As a preferred solution of the desulfurization wastewater desludging system of the present invention, the desludging unit further includes a desulfurization wastewater reaction module and a desulfurization wastewater flocculation module.

[0015] As a preferred solution of the desulfurization wastewater desludging system of the present invention, wherein: the sedimentation module includes a desulfurization wastewater pre-sedimentation tank; the clean water recovery module includes a desulfurization wastewater sedimentation clean water recovery pump; the clean water storage module includes an industrial wastewater tank; and the clean water discharge module includes a desulfurization wastewater clean water discharge pump.

[0016] As a preferred solution of the desulphurization wastewater desludging system of the present invention, the dosing module, the clean water recovery module, and the clean water discharge module are all provided with matching pumps, pipelines, and valves.

[0017] As a preferred solution of the desulphurization wastewater desludging system of the present invention, the sedimentation module and the clean water storage module are both equipped with dredging vehicles to regularly clean the sludge in the corresponding modules and transport the sludge to a recycling site.

[0018] The beneficial effects of the present invention are as follows: the present invention effectively improves the removal efficiency of solid matter in desulfurization wastewater through continuous, automatic and reliable operation, reduces the cost and time of manual cleaning, avoids water quality deterioration and membrane system blockage problems, ensures the continuity and stability of wastewater treatment, and contributes to environmental protection and resource recovery. In addition, the present invention can meet the wastewater recycling standards with only one dosing, improves the treatment efficiency, reduces the use of chemicals, and reduces potential pollution to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0020] Figure 1 Schematic diagram of the process for removing mud from desulfurization wastewater.

[0021] Figure 2 It is a schematic diagram of the first implementation method of the desulfurization wastewater desludging system.

[0022] Figure 3 It is a schematic diagram of the second implementation mode of the desulfurization wastewater desludging system. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0024] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0026] Example 1

[0027] Reference Figure 1, is an embodiment of the present invention, which provides a method for desludging desulfurization wastewater, which can solve the problem that the desulfurization wastewater pre-sedimentation tank cannot precipitate all solids, resulting in excessively high suspended solids content in the wastewater, affecting the operating efficiency and water quality of the subsequent membrane treatment system.

[0028] Specifically, the desulfurization wastewater is added with drugs, and the desulfurization wastewater after the addition of drugs enters the industrial wastewater pool for solid matter sedimentation;

[0029] The wastewater after solid precipitation is discharged to the preset liquid level and the treatment is stopped;

[0030] Automatically pneumatically stir and discharge solids in industrial wastewater pools through aeration;

[0031] The stirred mud-water mixture is discharged into the desulfurization wastewater pre-sedimentation tank for sedimentation.

[0032] Specifically, the added desulfurization wastewater enters the #2 / 3 / 4 industrial wastewater pool, and the desulfurization wastewater settles in the industrial wastewater pool for 120 hours to ensure that the solid matter in the wastewater is completely precipitated. Furthermore, the desulfurization wastewater settles in the #2 / 3 / 4 industrial wastewater pool. When the desulfurization system wastewater is continuously discharged, at the existing desulfurization wastewater discharge flow rate, the wastewater settling time of each industrial pool is 120 hours. After settling, it can ensure that all solid matter in the wastewater of the industrial wastewater pool is completely precipitated, and the turbidity entering the desulfurization wastewater membrane system is qualified. When the settling is completed, the solid matter in the #2 / 3 / 4 industrial wastewater pool is aerated to achieve automatic pneumatic stirring and automatic discharge. When compressed air enters the aeration port, mud and water stirring begins at the aeration port, and the stirred mud and water mixture is discharged into the wastewater pre-sedimentation tank through the automatic mud discharge system. Since the industrial wastewater tank is operated intermittently, the mud discharge system is also operated intermittently, and the wastewater pre-sedimentation tank is also operated intermittently. The sedimentation time of solid matter in the wastewater pre-sedimentation tank is as long as 7 days. Sufficient sedimentation time can ensure that all solid matter is completely precipitated in the wastewater pre-sedimentation tank. Finally, the desulfurization wastewater solid removal system realizes continuous, automatic and reliable operation.

[0033] In summary, the present invention effectively improves the removal efficiency of solid matter in desulfurization wastewater through continuous, automatic and reliable operation, reduces the cost and time of manual cleaning, avoids water quality deterioration and membrane system clogging problems, ensures the continuity and stability of wastewater treatment, and contributes to environmental protection and resource recovery. In addition, the present invention can meet the wastewater recycling standards with only one dosing, improves the treatment efficiency, reduces the use of chemicals, and reduces potential pollution to the environment.

[0034] Example 2

[0035] Reference Figure 1, which is the second embodiment of the present invention, provides a method for desludging desulfurization wastewater, which can solve the problem that the desulfurization wastewater pre-sedimentation tank cannot precipitate all solids, resulting in excessively high content of suspended solids in the wastewater, affecting the operating efficiency and water quality of the subsequent membrane treatment system.

[0036] Specifically, the desulfurization wastewater is added with drugs, and the desulfurization wastewater after the addition of drugs enters the industrial wastewater pool for solid matter sedimentation;

[0037] The wastewater after solid precipitation is discharged to the preset liquid level and the treatment is stopped;

[0038] Automatically pneumatically stir and discharge solids in industrial wastewater pools through aeration;

[0039] The stirred mud-water mixture is discharged into the desulfurization wastewater pre-sedimentation tank for sedimentation.

[0040] Furthermore, the industrial wastewater pool includes three industrial wastewater pools; when the desulfurized wastewater after adding chemicals is discharged into the industrial wastewater pool, the discharge is automatically stopped when the liquid level rises to a preset height.

[0041] It should be noted that the capacity of each industrial wastewater pool is 2600m 3 When the desulfurization system wastewater is discharged continuously, under the existing desulfurization wastewater discharge flow, when the three industrial wastewater pools are operated at intervals, the wastewater settling time of each industrial pool is 120 hours. After settling, it can ensure that all solid matter in the wastewater of the industrial wastewater pool is precipitated, and the turbidity entering the desulfurization wastewater membrane system is qualified.

[0042] Furthermore, the discharge treatment includes desulfurization wastewater membrane treatment technology, which discharges the wastewater after the solid matter has settled through membrane treatment, and automatically stops discharging when the liquid level drops to a preset height.

[0043] It should be noted that the desulfurization wastewater membrane treatment is of microfiltration type, with a pore size of 0.1-10 microns and an operating pressure of 1-3 bar, and is mostly used to remove suspended solids, bacteria and some large molecular organic matter.

[0044] Furthermore, aeration includes passing compressed air into an aeration port, and pneumatically stirring the remaining solid matter and wastewater at the aeration port to achieve mud and water mixing.

[0045] It should be noted that aeration includes 68 aeration ports (17 rows * 4 ports / row) evenly arranged at the bottom of the industrial wastewater pool (50m*12m*4.3m). The mud-water mixture stirred after aeration is discharged into the wastewater pre-sedimentation tank through the corresponding pipes.

[0046] Furthermore, the operation lines from the industrial wastewater pool to the wastewater pre-sedimentation tank are all timed intermittent operation, and the intermittent time includes the time required for the desulfurization wastewater to be discharged into or discharged to the preset water level, as well as the static sedimentation time.

[0047] In summary, the present invention effectively improves the removal efficiency of solid matter in desulfurization wastewater through continuous, automatic and reliable operation, reduces the cost and time of manual cleaning, avoids water quality deterioration and membrane system clogging problems, ensures the continuity and stability of wastewater treatment, and contributes to environmental protection and resource recovery. In addition, the present invention can meet the wastewater recycling standards with only one dosing, improves the treatment efficiency, reduces the use of chemicals, and reduces potential pollution to the environment.

[0048] Example 3

[0049] Reference Figure 2-3 , which is the third embodiment of the present invention, provides a desulphurization wastewater desludging system, which can solve the problem that the desulphurization wastewater pre-sedimentation tank 102a cannot precipitate all solids, resulting in excessively high content of suspended solids in the wastewater, affecting the operating efficiency and water quality of the subsequent membrane treatment system.

[0050] Specifically, the mud removal unit 100 includes a dosing module 101, a sedimentation module 102 connected to the dosing module 101, a clean water recovery module 103 connected to the sedimentation module 102, a clean water storage module 104 connected to the clean water recovery module 103, and a clean water discharge module 105 connected to the clean water storage module 104.

[0051] Furthermore, the desludging unit 100 also includes a desulfurization wastewater reaction module 106 and a desulfurization wastewater flocculation module 107 .

[0052] Furthermore, the sedimentation module 102 includes a desulfurization wastewater pre-sedimentation tank 102a; the clean water recovery module 103 includes a desulfurization wastewater sedimentation clean water recovery pump 103a; the clean water storage module 104 includes an industrial wastewater tank 104a; and the clean water discharge module 105 includes a desulfurization wastewater clean water discharge pump 105a.

[0053] Furthermore, the dosing module 101, the clean water recovery module 103, and the clean water discharge module 105 are all provided with matching pumps, pipelines, and valves.

[0054] Furthermore, the sedimentation module 102 and the clean water storage module 104 are both equipped with dredging vehicles to regularly clean the sludge in the corresponding modules and transport the sludge to a recycling site.

[0055] The operation logic of this system is that the desulfurization wastewater purification process is as follows: the desulfurization wastewater enters the reaction box, and organic sulfur is added to the reaction box at the same time, and flocculants and coagulants are added to the flocculation box to remove heavy metals, and the desulfurization wastewater after the addition of drugs is further discharged into the industrial wastewater pool 104a, and the sludge in the industrial wastewater pool 104a is finally filtered through sand filtration, ultrafiltration, nanofiltration, and reverse osmosis, and the clean water finally discharged is waiting to enter the recycling and reuse stage.

[0056] At the same time, the desulfurization wastewater sludge settling process is as follows: the desulfurization wastewater enters the reaction box, and organic sulfur is added to the reaction box at the same time, and flocculants and coagulants are added to the flocculation box to remove heavy metals, and the desulfurization wastewater after the addition of drugs is further discharged into the industrial wastewater pool 104a, and sludge is set in the industrial wastewater pool 104a. After the static sedimentation is completed, the mud-water mixture obtained after aeration is discharged into the desulfurization wastewater pre-sedimentation tank 102a, and sludge and mud removal are carried out in the desulfurization wastewater pre-sedimentation tank 102a.

[0057] Among them, the automatic operation logic of solid matter removal in the industrial wastewater pool 104a is that the desulfurized wastewater enters the #2 / 3 / 4 industrial wastewater pool 104a, and when the liquid level in the industrial wastewater pool 104a rises to 4.35m, the discharge of desulfurized wastewater is automatically stopped. At this time, the desulfurized wastewater is allowed to stand in the industrial wastewater pool 104a for 120 hours. When the standing is over, the desulfurized wastewater membrane treatment system is started to treat the wastewater in the industrial wastewater pool 104a. When the liquid level of the wastewater discharged into the industrial wastewater pool 104a drops to 1.5m, the desulfurized wastewater membrane treatment system is automatically stopped, and the aeration fan is started at the same time. After the aeration fan is started for 30 minutes, the industrial wastewater pump is further started to discharge mud, and the mud-water mixture is discharged into the desulfurized wastewater pre-sedimentation tank 102a through a pipeline. Further, when the liquid level in the industrial wastewater pool 104a drops to 0.5m, the industrial wastewater pump is automatically stopped, and the aeration fan is stopped at the same time.

[0058] In summary, the present invention effectively improves the removal efficiency of solid matter in desulfurization wastewater through continuous, automatic and reliable operation, reduces the cost and time of manual cleaning, avoids water quality deterioration and membrane system clogging problems, ensures the continuity and stability of wastewater treatment, and contributes to environmental protection and resource recovery. In addition, the present invention can meet the wastewater recycling standards with only one dosing, improves the treatment efficiency, reduces the use of chemicals, and reduces potential pollution to the environment.

[0059] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible without substantially departing from the novel teachings and advantages of the subject matter described in the application (e.g., mounting arrangements, use of materials, color, changes in orientation, etc.). For example, the element shown as integrally formed may be composed of a plurality of parts or elements, the position of the element may be inverted or otherwise changed, and the nature or number or position of the discrete element may be altered or changed. Therefore, all such modifications are intended to be included within the scope of the present invention. The order or sequence of any process or method steps may be changed or reordered according to an alternative embodiment. In the claims, any "bracket plus function" clause is intended to cover the structure of the execution function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the present invention is not limited to a specific embodiment, but extends to a variety of modifications that still fall within the scope of the appended claims.

[0060] Additionally, in an effort to provide a concise description of example embodiments, all features of an actual implementation may not be described.

[0061] It should be understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but for those of ordinary skill having the benefit of this disclosure, the development effort will be a routine task of design, fabrication, and production without undue experimentation.

[0062] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for removing mud from desulfurization wastewater, characterized in that: include, Adding chemicals to the desulfurization wastewater, so that the desulfurization wastewater after adding chemicals enters the industrial wastewater pool for solid sedimentation; The wastewater after solid precipitation is discharged to the preset liquid level and the treatment is stopped; Automatically pneumatically stir and discharge solids in industrial wastewater pools through aeration; The stirred mud-water mixture is discharged into the desulfurization wastewater pre-sedimentation tank for sedimentation.

2. The method for desludging desulfurization wastewater according to claim 1, characterized in that: The industrial wastewater pool includes three industrial wastewater pools; when the desulfurized wastewater after adding drugs is discharged into the industrial wastewater pool, the discharge is automatically stopped when the liquid level rises to a preset height.

3. The method for desludging desulfurization wastewater according to claim 2, characterized in that: The discharge treatment includes desulfurization wastewater membrane treatment technology, which discharges the wastewater after the solid matter has settled through membrane treatment, and automatically stops discharging when the liquid level drops to a preset height.

4. The method for desludging desulfurization wastewater according to claim 3, characterized in that: The aeration includes passing compressed air into an aeration port, pneumatically stirring the remaining solid matter and wastewater at the aeration port to achieve mud and water mixing.

5. The method for desludging desulfurization wastewater according to claim 4, characterized in that: The operation lines from the industrial wastewater pool to the wastewater pre-sedimentation tank are all timed intermittent operations, and the intermittent time includes the time required for the desulfurization wastewater to be discharged into or discharged to the preset water level, as well as the static sedimentation time.

6. A desludging system for desulfurization wastewater, applicable to a method for desludging desulfurization wastewater, characterized in that: include, The mud removal unit (100) comprises a dosing module (101), a sedimentation module (102) connected to the dosing module (101), a clean water recovery module (103) connected to the sedimentation module (102), a clean water storage module (104) connected to the clean water recovery module (103), and a clean water discharge module (105) connected to the clean water storage module (104).

7. The desulphurization wastewater desludging system according to claim 6, characterized in that: The desludging unit (100) further comprises a desulfurization wastewater reaction module (106) and a desulfurization wastewater flocculation module (107).

8. The desulphurization wastewater desludging system according to claim 7, characterized in that: The sedimentation module (102) includes a desulfurization wastewater pre-sedimentation tank (102a); the clean water recovery module (103) includes a desulfurization wastewater sedimentation clean water recovery pump (103a); the clean water storage module (104) includes an industrial wastewater tank (104a); and the clean water discharge module (105) includes a desulfurization wastewater clean water discharge pump (105a).

9. The desulphurization wastewater desludging system according to claim 8, characterized in that: The drug adding module (101), the clean water recovery module (103), and the clean water discharge module (105) are all provided with matching pumps, pipelines, and valves.

10. The desulphurization wastewater desludging system according to claim 9, characterized in that: The sedimentation module (102) and the clean water storage module (104) are both equipped with dredging vehicles to regularly clean the sludge in the corresponding modules and transport the sludge to a recycling location.

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