Zero-discharge integrated treatment system for desulfurization wastewater of high-sulfur lignite unit
By building a zero-emission integrated treatment system for desulfurization wastewater in high-sulfur lignite units, using high-efficiency clarifiers and reuse components, the problems of excessive discharge of desulfurization wastewater and unused cooling water are solved, effective reuse of wastewater and cascade utilization of resources are achieved, and the risk of system corrosion is reduced.
Patent Information
- Application Number
- CN202422923006.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-08-19
- Estimated Expiration
- 2034-11-29
AI Technical Summary
In the prior art, the wastewater discharge of the desulfurization system of the high-sulfur lignite unit is too large, exceeding the designed capacity, resulting in corrosion and chloride ion enrichment in industrial wastewater systems, unable to meet emission standards, and failing to effectively utilize cooling water resources, which violates the principle of cascade utilization.
Using components such as triple boxes, integrated powder dosing machines, electromagnetic flowmeters, high-efficiency clarifiers, water tanks, sludge boxes and wastewater buffer boxes, a integrated treatment system for desulfurization wastewater from high-sulfur lignite units is constructed. The wastewater is treated through an efficient clarifier and reused to the ash reservoir clean water tank and ash field to suppress dust, recycle the cooling water to the industrial wastewater tank, and directly re-use the slurry circulation pump to seal the cooling water to the desulfurization system.
Effectively reduce the discharge of desulfurization wastewater, avoid vicious cycles, reduce corrosion in industrial wastewater systems, realize the cascade utilization of wastewater, and meet environmental protection and resource utilization requirements.
Smart Images
Figure CN223239881U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of wastewater treatment, in particular to a zero-discharge integrated treatment system for desulfurization wastewater from a high-sulfur lignite unit. Background Art
[0002] The desulfurization system's process water source is recycled water or recycled wastewater, while industrial water is used for cooling the desulfurization auxiliary equipment. The process water system meets the needs of the desulfurization process system during both normal operation of the FGD unit and during emergency conditions. The process water supply system includes a process water tank, two process water pumps (one in service and one in backup), and four demister flushing pumps (two in service and one in backup). The process water is divided into two routes. One route is for demister flushing, supplied by the demister flushing pumps. Its primary function is to flush the demisters above the absorber and provide make-up water for the absorber. The other route is for process water, supplied by the process water pumps. Its primary function is to flush all slurry handling equipment, pipelines, and storage tanks. The desulfurization wastewater treatment system is designed for a total wastewater discharge of 7 tons / h when a single furnace is operating at full load. Assuming the wastewater system output is 150%, the designed treatment capacity is 21 tons / h. The desulfurization wastewater treatment system comprises three subsystems: the desulfurization unit wastewater treatment system, the chemical dosing system, and the sludge dewatering system. After desulfurization wastewater undergoes neutralization (alkalinization) and flocculation treatment, it is sent to a clarifier / concentrator. Acid is added to the effluent in a final neutralization / oxidation tank to adjust the pH. Once the pH reaches the standard, the wastewater is pumped to the power plant for ash humidification or on-site wastewater treatment. The sludge at the bottom of the clarifier / concentrator tank is pumped to the original power plant wastewater treatment centrifuge via a sludge transfer pump for desludge cake transportation.
[0003] Because the gypsum produced by the power plant's desulfurization system is currently sold externally, according to the agreement, the chloride ion concentration in the sold gypsum must be less than 100 mg / kg. This limits the control of chloride ion concentration in the slurry during desulfurization system operation, resulting in increased desulfurization system wastewater discharge, exceeding the maximum design capacity of the triple-tank treatment system (designed for a 0.5-hour residence time). Furthermore, during high-load operation of the dual-unit system, the desulfurization wastewater cannot be effectively treated. Furthermore, the desulfurization system currently lacks a clarification / concentration tank and a desludging system. After treatment in the triple-tank, the desulfurization wastewater is directly discharged into the concentrator tank of the industrial wastewater system. This does not meet the workshop discharge port index requirements in the discharge permit and is prone to corrosion of the industrial wastewater concentrator pipes. Furthermore, the concentrator effluent ultimately enters the reuse water system, which can also cause corrosion in the reuse water system pipes. After the reuse water is added to the desulfurization system, chloride ions accumulate within the desulfurization system, leading to increased desulfurization wastewater discharge, creating a vicious cycle.
[0004] The cooling water and slurry circulation pump seal of the desulfurization system pulping system use industrial water that is not recycled to the industrial water system for recycling, resulting in high quality and low use, which does not comply with the principle of cascade utilization. Utility Model Content
[0005] The utility model proposes an integrated zero-discharge treatment system for desulfurization wastewater from a high-sulfur lignite unit to solve the problems raised in the above-mentioned background technology.
[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions: application of high sulfur lignite unit desulfurization wastewater zero discharge integrated treatment system,
[0007] Including triple box, integrated powder dosing machine, electromagnetic flowmeter, high-efficiency clarifier, clean water tank, sludge tank, wastewater buffer tank,
[0008] The triple box is provided with a dosing box, a reaction box and a flocculation box from left to right.
[0009] The desulfurization wastewater treated by the high-efficiency clarifier is stored in a clean water tank. Clean water recycling pumps A and B are provided at the water outlet of the clean water tank. The treated desulfurization wastewater is recycled to the ash storage clean water tank through the clean water recycling pumps A and B. The other route leads to the ash field dust suppression pipeline for use as water for dust suppression in the ash field. If the effluent quality is unqualified, it will be returned to the wastewater buffer tank for treatment.
[0010] The sludge discharged from the high-efficiency clarifier and the sludge stored in the sludge box are discharged to the downpipe of the gypsum cyclone through the sludge delivery pump A, the sludge delivery pump B and the pipeline, and this part of the water is consumed by the gypsum cyclone;
[0011] The wastewater buffer tank is used for caching, homogenizing and pre-precipitating desulfurization wastewater. Wastewater transfer pump A and wastewater transfer pump B are provided at the outlet of the wastewater buffer tank. The desulfurization wastewater is transported to the wastewater treatment equipment for treatment through wastewater transfer pump A and wastewater transfer pump B.
[0012] Furthermore, the cooling water produced by the high-efficiency clarifier and the clean water tank is recycled into the industrial wastewater pool.
[0013] Furthermore, the electromagnetic flowmeter is installed at the following three locations: the rear pipeline of the clean water reuse pump A and the clean water reuse pump B, between the wastewater buffer tank and the desulfurization wastewater inlet pipeline, and between the wastewater buffer tank and the triplex tank.
[0014] Furthermore, the top of the dosing box is connected to an integrated powder dosing machine.
[0015] Furthermore, the overflow port of the triple tank is connected to the high-efficiency clarifier through a pipeline.
[0016] Furthermore, the wastewater buffer tank is connected to a desulfurization wastewater inlet pipeline.
[0017] Furthermore, the wastewater buffer tank and the wastewater transfer pump A and the wastewater transfer pump B are connected to a process water pipeline.
[0018] Compared with the existing technology, the advantages and positive effects of the utility model are: the desulfurization wastewater zero-discharge integrated treatment system of the high-sulfur lignite unit is stored in the clean water tank after being treated by the high-efficiency clarifier, and the treated desulfurization wastewater is recycled to the ash storage clean water pool through the clean water recycling pump, and the other route is used as dust suppression water in the ash field, thereby effectively utilizing the desulfurization wastewater, greatly reducing the discharge of desulfurization wastewater, and avoiding a vicious cycle; the cooling water generated by the high-efficiency clarifier and the clean water tank is recycled to the industrial wastewater pool, and the cooling water of the desulfurization pulping system is directly recycled to the industrial water pool; the slurry circulation pump machine seal cooling water is directly recycled to the desulfurization system; the recycling is in line with the principle of cascade utilization. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 This is the process system diagram of the utility model;
[0020] Figure 2 This is a system flow chart of the utility model;
[0021] Figure 3 It is a flow chart of an existing system in the background technology.
[0022] In the figure: 1. triple box, 11. dosing box, 12. reaction box, 13. flocculation box, 2. integrated powder dosing machine, 3. electromagnetic flowmeter, 4. high-efficiency clarifier, 41. clean water tank, 42. industrial wastewater tank, 43. clean water reuse pump A, 44. clean water reuse pump B, 45. ash field dust suppression pipeline, 46. ash storage clean water tank, 47. sludge box, 471. sludge conveying pump A, 472. sludge conveying pump B, 5. wastewater buffer tank, 51. wastewater transfer pump A, 52. wastewater transfer pump B, 6. process water, 7. desulfurization wastewater inlet 7. DETAILED DESCRIPTION
[0023] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other without conflict.
[0024] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.
[0025] Example 1
[0026] like Figure 1 As shown, the utility model provides a zero-discharge integrated treatment system for desulfurization wastewater from high-sulfur lignite units.
[0027] It includes a triple box 1, a dosing box 11, a reaction box 12, a flocculation box 13, an integrated powder dosing machine 2, an electromagnetic flowmeter 3,
[0028] High-efficiency clarifier 4, clean water tank 41, industrial wastewater tank 42, clean water recycling pump A43, clean water recycling pump B44, ash field dust suppression pipeline 45, ash storage clean water tank 46, sludge tank 47, sludge delivery pump A471, sludge delivery pump B472,
[0029] Wastewater buffer tank 5, wastewater transfer pump A51, wastewater transfer pump B52, process water 6, desulfurization wastewater 7;
[0030] The triple box 1 is provided with a dosing box 11, a reaction box 12 and a flocculation box 13 from left to right. The top of the dosing box 11 is connected to the integrated powder dosing machine 2.
[0031] The overflow port of the triple box 1 is connected to the high-efficiency clarifier 4 through a pipeline. The desulfurization wastewater treated by the high-efficiency clarifier 4 is stored in the clean water tank 41. The outlet of the clean water tank 41 is provided with a clean water recycling pump A43 and a clean water recycling pump B44. The treated desulfurization wastewater is recycled to the ash storage clean water tank 46 through the clean water recycling pump A43 and the clean water recycling pump B44, and the other route is connected to the ash yard dust suppression pipeline 45 for use as water for dust suppression in the ash yard; the desulfurization wastewater treated by the high-efficiency clarifier is stored in the clean water tank, and two new clean water recycling pumps are added, one for use and one for backup. The treated desulfurization wastewater and qualified clean water are recycled to the ash storage clean water tank through the clean water recycling pump, and the other route is used as water for dust suppression in the ash yard, thereby effectively utilizing the desulfurization wastewater; if the effluent quality is unqualified, it is returned to the wastewater buffer tank 5 for treatment; the cooling water generated by the high-efficiency clarifier 4 and the clean water tank 41 is recycled to the industrial wastewater pool 42;
[0032] The sludge discharged from the high-efficiency clarifier 4 and the sludge stored in the sludge box 47 are discharged to the downpipe of the gypsum cyclone through the sludge delivery pump A471 and the sludge delivery pump B472 and the pipeline. This part of the water is consumed by the gypsum cyclone. An additional ash removal pipeline is provided for use in emergency situations.
[0033] The wastewater buffer tank 5 is connected to the desulfurization wastewater inlet water pipeline 7. The wastewater buffer tank 5 is used for caching, homogenizing and pre-precipitation of desulfurization wastewater. A wastewater transfer pump A51 and a wastewater transfer pump B52 are provided at the outlet of the wastewater buffer tank 5. The desulfurization wastewater is transported to the wastewater treatment equipment for treatment through the wastewater transfer pump A51 and the wastewater transfer pump B52. The process water inlet water pipeline 6 is connected between the wastewater buffer tank 5 and the wastewater transfer pump A51 and the wastewater transfer pump B52.
[0034] In addition, the slurry circulation pump seal cooling water is directly recycled into the desulfurization system.
[0035] The electromagnetic flowmeter 3 is installed at the following three locations: the pipeline behind the clean water reuse pump A43 and the clean water reuse pump B44, between the wastewater buffer tank 5 and the desulfurization wastewater inlet water pipeline 7, and between the wastewater buffer tank 5 and the triple tank 1.
[0036] Example 2
[0037] 1) Build a new desulfurization wastewater buffer tank (V=200m3, size φ6.5m, H=6m), arranged on the ground, with carbon steel rubber lining, for desulfurization wastewater buffer, homogenization and pre-precipitation. Add 2 desulfurization wastewater transfer pumps (Q=25m 3 / h, H=35m), one in use and one in reserve, arranged at the outlet of the newly built desulfurization wastewater buffer tank, and the desulfurization wastewater is transported to the wastewater treatment equipment for treatment through the desulfurization wastewater transfer pump, and a new pipeline (DN65, 316L or 2205 stainless steel pipe) is added.
[0038] 2) Build a new high-efficiency clarification / concentration tank (Q = 25m 3 / h, size φ5m, H=6m), arranged on the ground, made of stainless steel, arranged in an open space near the industrial wastewater treatment system, and a new clean water tank (V=200m 3 , size φ6m, H=7m) and a sludge tank (V=30m 3 , size φ3m, H=4.5m), arranged on the ground, made of 316L or 2205 stainless steel, arranged next to the newly built clarification / concentration tank.
[0039] 3) The effluent from the clarification / concentration tank is connected to the newly built clean water tank through an overhead pipeline (DN125, 316L or 2205 stainless steel pipe), and the treated clean water is discharged into the newly built clean water tank.
[0040] 4) Two new sludge pumps (Q=20m 3 / h, H = 35m), one for use and one for backup, the sludge discharged from the clarification / concentration tank and the sludge stored in the sludge box are discharged to the gypsum cyclone downpipe through the sludge transfer pump, and an additional ash removal pipeline is added for use in emergency situations. At the same time, two new clean water recycling pumps (Q = 100m 3 / h, H=40m), one for use and one for backup, arranged at the outlet of the clean water tank. The clean water in the clean water tank is controlled by an electric butterfly valve. Qualified clean water is recycled to the clean water pool in the ash storage and for dust suppression in the ash field. If the outlet water quality is unqualified, it will be returned to the buffer tank for treatment.
[0041] 5) Added supporting cables, pipelines, electrical, control, lighting and other work content.
[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in any other form. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification of the above embodiment made according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of protection of the technical solution of the present invention.
Claims
1. An integrated zero-discharge treatment system for desulfurization wastewater from a high-sulfur lignite unit, comprising a triple tank (1), an integrated powder dosing machine (2), an electromagnetic flowmeter (3), a high-efficiency clarifier (4), a clean water tank (41), a sludge tank (47), and a wastewater buffer tank (5), characterized in that: The triple box (1) is provided with a dosing box (11), a reaction box (12) and a flocculation box (13) in sequence from left to right; The desulfurization wastewater treated by the high-efficiency clarifier (4) is stored in a clean water tank (41). A clean water recycling pump A (43) and a clean water recycling pump B (44) are provided at the outlet of the clean water tank (41). The treated desulfurization wastewater is recycled to the ash storage clean water tank (46) through the clean water recycling pump A (43) and the clean water recycling pump B (44). The other route leads to the ash field dust suppression pipeline (45) for use as water for ash field dust suppression. If the effluent water quality is unqualified, it is returned to the wastewater buffer tank (5) for treatment. The sludge discharged from the high-efficiency clarifier (4) and the sludge stored in the sludge box (47) are discharged to the gypsum cyclone downpipe through the sludge delivery pump A (471), the sludge delivery pump B (472) and the pipeline, and this part of the water is consumed by the gypsum cyclone; The wastewater buffer tank (5) is used for caching, homogenizing and pre-precipitating desulfurized wastewater. A wastewater transfer pump A (51) and a wastewater transfer pump B (52) are provided at the outlet of the wastewater buffer tank (5). The desulfurized wastewater is transported to the wastewater treatment equipment for treatment via the wastewater transfer pump A (51) and the wastewater transfer pump B (52).
2. The zero-discharge integrated treatment system for desulfurization wastewater from a high-sulfur lignite unit according to claim 1 is characterized in that: The cooling water produced by the high-efficiency clarifier (4) and the clean water tank (41) is recycled into the industrial wastewater pool (42).
3. The zero-discharge integrated treatment system for desulfurization wastewater from a high-sulfur lignite unit according to claim 1 is characterized in that: The electromagnetic flowmeter (3) is installed at the following three locations: the pipeline behind the clean water recycling pump A (43) and the clean water recycling pump B (44), between the wastewater buffer tank (5) and the desulfurization wastewater inlet (7) pipeline, and between the wastewater buffer tank (5) and the triple tank (1).
4. The zero-discharge integrated treatment system for desulfurization wastewater from high-sulfur lignite units according to claim 1 is characterized in that: The top of the dosing box (11) is connected to the integrated powder dosing machine (2).
5. The zero-discharge integrated treatment system for desulfurization wastewater from high-sulfur lignite units according to claim 1 is characterized in that: The overflow port of the triple box (1) is connected to the high-efficiency clarifier (4) through a pipeline.
6. The zero-discharge integrated treatment system for desulfurization wastewater from high-sulfur lignite units according to claim 1 is characterized in that: The wastewater buffer tank (5) is connected to a desulfurization wastewater inlet (7) pipeline.
7. The zero-discharge integrated treatment system for desulfurization wastewater from a high-sulfur lignite unit according to claim 1 is characterized in that: The wastewater buffer tank (5) is connected to the wastewater transfer pump A (51) and the wastewater transfer pump B (52) via a process water inlet (6) pipeline.