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CN-121972295-A - Wet-type electric precipitation water system and method based on wet desulfurization system

CN121972295ACN 121972295 ACN121972295 ACN 121972295ACN-121972295-A

Abstract

The invention discloses a wet electric precipitation water system and a wet electric precipitation water method based on a wet desulfurization system, and belongs to the technical field of flue gas purification of coal-fired power plants. The system comprises a process water tank, a process water pump, a demister flushing water pump and a wet electric dust collector and desulfurization system, wherein the wet electric dust collector is not provided with an independent circulating water system and a clarification reuse water system, one path of process water is led out by the demister flushing water pump to serve as a flushing water source, and the flushed waste water directly enters a wet electric dust collector ash bucket from a self-flowing mode and flows back to the desulfurization system for recycling. The invention also optimizes the flushing operation logic that the cathode system adopts low-frequency manual periodical flushing and the anode system adopts high-frequency automatic intermittent flushing. By canceling complex wastewater treatment and circulation equipment, the invention obviously reduces the investment cost, the operation energy consumption and the maintenance workload of the system on the premise of ensuring the dust removal performance, and realizes the simplification of the system flow and the efficient cascade utilization of water resources.

Inventors

  • MAO XIAOYU
  • XU CHENGLIANG
  • WANG JIANYANG
  • PAN CHAOQUN
  • ZHOU TAO
  • DU XIAOJING
  • XU XIANG
  • HUANG CHUNWEI

Assignees

  • 浙江浙能科技环保集团股份有限公司

Dates

Publication Date
20260505
Application Date
20260310

Claims (8)

  1. 1. The wet electric dust removal water system based on the wet desulfurization system is characterized by comprising a process water tank (2), a process water pump (1), a demister flushing water pump (3), wet electric dust removal (4), a wet electric dust removal ash bucket (5) and a desulfurization system (6); The inlet of the process water tank (2) is communicated with a process water conveying pipeline; the flushing water of the wet electric precipitation (4) is a single water source channel, and the single water source is led from the outlet of the process water tank (2) to the outlet main pipe of the demister flushing water pump (3); The bottom water outlet of the wet electric dust collector (4) is communicated with the inlet of the wet electric dust collector ash bucket (5), and the waste water generated after the wet electric dust collector (4) is washed is directly discharged into the wet electric dust collector ash bucket (5) and then is returned to the desulfurization system for reuse.
  2. 2. The wet electric precipitation water system based on the wet desulfurization system according to claim 1 is characterized in that an outlet pipeline of the process water tank (2) is divided into three branches, specifically, an outlet of the process water tank (2) is connected with a first branch (10), a process water pump (1) is arranged on the first branch (10), the process water pump (1) is led out, the first branch (10) is directly communicated with the desulfurization system (6), a demister flushing water pump (3) is arranged on the other outlet pipeline of the process water tank (2), the outlet of the demister flushing water pump (3) is led out and divided into two branches, namely a second branch (7) and a third branch (8), the second branch (7) is communicated with an absorber demister in the desulfurization system (6) for intermittent flushing, water after flushing flows back to the desulfurization system (6), and the third branch (8) is used as the single water source channel to be communicated with the wet electric precipitator (4).
  3. 3. Wet electric precipitation water system based on wet desulfurization system according to claim 2, characterized in that the outlet of the wet electric precipitation ash bucket (5) is connected to the desulfurization system (6) through a wet electric precipitation drainage branch (9), and the flushing wastewater of the third branch (8) is returned to the desulfurization system (6) through the wet electric precipitation drainage branch (9) after flowing out from the wet electric precipitation ash bucket (5).
  4. 4. The wet electric precipitation water system based on the wet desulfurization system according to claim 2, wherein the process water consumption ratio of the three waterways is that the water consumption of the first branch (10) accounts for 3-5% of the total process water consumption, the water consumption of the second branch (7) accounts for 45-60% of the total process water consumption, and the water consumption of the third branch (8) accounts for 37-50% of the total process water consumption. The total water consumption of the three branches is 100 percent.
  5. 5. Method of operating a wet electrostatic precipitator water system based on a wet desulfurization system according to any of claims 1-4, comprising the following control of the flushing logic of the wet electrostatic precipitator (4): carrying out periodic manual flushing on a cathode system of the wet electric precipitation (4); Intermittent automatic flushing is carried out on the anode system of the wet electric precipitation (4).
  6. 6. The method for operating a wet electric dust collector system based on a wet desulfurization system according to claim 5, wherein the set washing cycle of the cathode system is 1 time every 2 weeks, the single washing time is 10-15 minutes, the washing is performed by electric field one by one, and the electric field voltage and the anode washing are stopped during the washing.
  7. 7. The operation method of wet electric dust collector water system based on wet desulfurization system according to claim 5, wherein the set operation logic of the anode system flushing is 2 hours after each 4 hours of operation, the daily accumulated flushing time is 8 hours, and the water inlet is controlled by a pneumatic valve and is linked with a water pump during flushing.
  8. 8. The operation method of a wet electric dust removal water system based on a wet desulfurization system according to claim 5, wherein the average flushing water quantity of the wet electric dust removal system (4) is consistent with the process water quantity of the third branch (8), the dust content of the flushed waste water is extremely low, and the waste water is directly recycled to the desulfurization system (6) without damaging the water balance of the desulfurization system (6).

Description

Wet-type electric precipitation water system and method based on wet desulfurization system Technical Field The invention belongs to the technical field of wet desulfurization systems, and particularly relates to a wet electric precipitation water system matched with a wet desulfurization system for industrial scenes such as coal-fired power plants and an operation method thereof. Background During recent ten years of domestic ultra-low emission reformation, in order to meet stricter environmental protection requirements, many coal-fired power plants are provided with a traditional wet electric dust removal system behind a desulfurization absorption tower. In the ultra-low emission modification process of coal-fired power plants, a wet electric dust collector is often arranged at the rear end of a wet desulphurization system and is used for further removing fine particles (such as dust, gypsum slurry drops and the like) in flue gas so as to meet increasingly strict environmental protection standards. Conventional wet electric precipitation water systems are generally equipped with independent circulating water systems and clarified reuse water systems in order to ensure the cleaning of the electrode plates and the wet electric precipitation efficiency, referring to fig. 2. The typical process is that the waste water after washing the wet electric dust removing polar plate is collected in an ash bucket, part of the waste water enters a circulating water system (usually comprising a circulating water tank, a circulating water pump, an alkali liquid tank, an alkali liquid pump and the like, and sometimes an alkali adding device is also included to adjust the pH value), and is circulated for polar plate washing after simple treatment, and the other part of the waste water is discharged as wet electric dust removing waste water. Because the discharged wastewater contains suspended matters with higher concentration, a complex clarifying reuse water system is required to be introduced for treatment, and the wastewater can be recycled or discharged after reaching standards. Typical clarification reuse systems include waste water tanks, pre-clarifiers, waste water pumps, sludge pumps, demister wash tanks, demister wash pumps, and the like. The circulating water system and the clarifying reuse water system configured by the system have the advantages of more equipment, high investment cost, high operation cost and high maintenance cost. The traditional water system has the obvious defects that 1) equipment is numerous, investment is high, a circulating system and a clarifying system relate to a plurality of tanks, pumps, pipelines and dosing equipment, and initial construction cost is high. 2) The operation and maintenance are complex, the cost is high, the workload of operation, monitoring and maintenance of a plurality of sets of systems is huge, and the energy consumption, the medicament consumption and the labor cost are high. 3) The system occupies a large area and is complex in field layout. In recent years, with the progress of technologies of upstream dust removal (such as electric dust removal and cloth bag dust removal) and in a desulfurizing tower (such as efficient spraying and demister), the dust content of flue gas entering the terminal wet electric dust removal has been greatly reduced. Meanwhile, various processes of the wet type electric precipitation body technology are improved and improved continuously, and continuous flushing is not needed in operation of wet type electric precipitation flushing water. In this context, continuing to use traditional complex water systems designed for high-load dust conditions has been redundant and uneconomical. Therefore, there is a need to optimize the existing wet electric precipitation water system, and there is a need for a new water system scheme that can adapt to new working conditions, greatly simplify the system and reduce investment and operation cost on the premise of guaranteeing the wet electric precipitation performance. Disclosure of Invention Aiming at the defects in the prior wet electric precipitation water system technology, the invention provides a wet electric precipitation water system and a wet electric precipitation water system method based on a wet desulfurization system, and the system cancels an independent circulating water system and a clarified reuse water system through process innovation, thereby realizing the direct and closed-loop recycling of wastewater in the desulfurization system, and further achieving the purposes of simplifying the system, reducing the cost and being convenient for operation and maintenance. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a wet electric dust-removing water system based on a wet desulfurization system comprises a process water tank, a process water pump, a demister flushing water pump, wet electric dust removal, a wet electric dust-removing