CN-122006459-A - Desulfurization absorption tower slurry treatment system and method

CN122006459ACN 122006459 ACN122006459 ACN 122006459ACN-122006459-A

Abstract

The invention discloses a slurry treatment system and method for a desulfurization absorption tower, and aims to solve the technical problems of low utilization rate of an accident slurry tank and poor separation effect of a wastewater cyclone station on fine particles in the existing wet desulfurization system. On the basis of retaining the original emergency function of the accident slurry tank, the system is improved into an integrated unit with the gravity sedimentation function by additionally arranging a bypass pipeline, a side stirrer, a liquid level mud level monitoring and a clear liquid discharging port. And when the desulfurization system is in normal operation, introducing overflow slurry of the gypsum cyclone station into an accident slurry tank for full sedimentation, discharging separated supernatant as high-quality wastewater raw water, and recycling bottom concentrated slurry into an absorption tower or a gypsum dehydration system. The invention realizes the high-efficiency utilization of idle equipment, strengthens the removal capability of fine particles and chloride ions in slurry, improves the quality of desulfurization wastewater and gypsum products, realizes the automatic and flexible switching of operation modes through a control system, and improves the operation stability and economy of the whole desulfurization system.

Inventors

ZHAO GUOPING
MAO XIAOYU
WANG RUNENG
WU HUAQIANG
LIN SHENGHU
HUANG GUANGFA
LAI CHUNFANG
CHEN ZHONGHUI

Assignees

浙江浙能科技环保集团股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260323

Claims (10)

1. The slurry treatment system of the desulfurization absorption tower comprises a desulfurization absorption tower (1), a gypsum discharge pump (6), a gypsum cyclone station (7), a vacuum belt conveyor (8), a reuse water tank (9), a wastewater cyclone station supply box (11), a wastewater cyclone station supply pump (12), a wastewater cyclone station (13), a desulfurization wastewater pre-sedimentation tank (14), a desulfurization wastewater treatment system (15) and a control system (16), and is characterized by further comprising a locally modified accident slurry tank (4); The feeding port of the gypsum cyclone station (7) is connected with the slurry discharge end of the desulfurization absorption tower (1) through the gypsum discharge pump (6), the bottom flow port is used for outputting gypsum slurry to the vacuum belt conveyor (8), and the overflow port is divided into two paths, namely, a first path is connected to the reuse water tank (9), and a second path is connected to the wastewater cyclone station supply tank (11), wherein the outlet of the wastewater cyclone station supply tank (11) is connected to the wastewater cyclone station (13) through the wastewater cyclone station supply pump (12); the waste water cyclone station (13) is characterized in that a bottom flow port of the waste water cyclone station is communicated with a recycling water tank (9), and an overflow port of the waste water cyclone station is communicated with a desulfurization waste water pre-sedimentation tank (14); the device comprises an accident slurry tank (4) serving as a core sedimentation unit, a slurry feeding pipe, a supernatant discharging pipe, a bottom stirring device, an accident slurry pump (5) and a liquid level mud level monitoring unit, wherein the slurry feeding pipe is connected with a bypass outlet of a wastewater cyclone station supply pump (12), an inlet of the accident slurry pump (5) is communicated with the bottom of the accident slurry tank (4), and an outlet of the accident slurry pump is divided into two paths, wherein one path is connected to a desulfurization absorption tower (1), and the other path is connected to a feeding end of a vacuum belt conveyor (8); The control system (16) is in signal connection with the slurry feed pipe, the valve on the supernatant discharge pipe, the bottom stirring device, the bottom mud discharge pump (5) and the liquid level mud level monitoring unit, and is configured to control the accident slurry tank (4) to automatically switch between a sedimentation mode and an emergency mode according to monitoring data, and perform feeding, sedimentation, drainage and mud discharge operation cycles in a sequencing batch mode.
2. A desulfurization absorber slurry treatment system according to claim 1, wherein said slurry feed pipe is connected to a bypass outlet of a waste water cyclone station feed pump (12) for receiving overflow slurry from said gypsum cyclone station (7); The inlet of the supernatant discharge pipe is arranged at a preset height on the inner wall of the accident slurry tank (4), and the outlet of the supernatant discharge pipe is connected to the water inlet end of the desulfurization wastewater pre-sedimentation tank (14); the bottom stirring device is arranged at the bottom or the side lower part of the accident slurry tank (4) and is used for stirring the settled concentrated bottom mud; The liquid level mud level monitoring unit is used for monitoring the interface height of clear liquid and mud in the accident slurry tank (4) in real time.
3. The slurry treatment system of a desulfurization absorption tower according to claim 1, wherein the side wall of the accident slurry tank (4) is provided with at least one peep mirror with an inner scraper, and the installation height of the peep mirror corresponds to the vicinity of a designed solid-liquid separation interface for observing sedimentation effect and performing mirror self-cleaning.
4. A desulfurization absorption tower slurry treatment system according to claim 3, wherein the inlet of the supernatant discharge pipe is provided at a position 0.3 m to 1.0 m above the designed solid-liquid separation interface on the inner wall of the accident slurry tank (4) to prevent disturbance of the bottom mud layer during the water discharge.
5. The slurry treatment system of the desulfurization absorption tower according to claim 1, wherein the outlet of the reuse water tank (9) is connected to the inlet of the desulfurization absorption tower (1) through a reuse water pump (10), and the outlet of the desulfurization wastewater pre-sedimentation tank (14) is communicated to the desulfurization wastewater treatment system (15).
6. The desulfurization absorption tower slurry treatment system according to claim 1, wherein the desulfurization absorption tower (1) is further provided with a second slurry discharge end, the accident slurry tank (4) is further provided with a second slurry feed pipe, the second slurry discharge end is communicated with the regional slurry tank (2), and an outlet of the regional slurry tank (2) is communicated with the second slurry feed pipe of the accident slurry tank (4) after passing through the regional slurry tank slurry pump (3).
7. The desulfurization absorption tower slurry treatment system according to claim 1, wherein the control system (16) is configured to automatically switch to an emergency mode when the liquid level of the emergency slurry tank (4) reaches a high limit or an emergency function needs to be started, stop feeding the emergency slurry into the emergency slurry tank (4) and prepare to receive the emergency slurry from the desulfurization absorption tower (1), and automatically start the supernatant discharge pipe for discharging after the slurry in the emergency slurry tank (4) reaches a set settling time and a solid-liquid interface is clear in a settling mode, close after the supernatant is discharged to a low liquid level, and start the bottom stirring device and the emergency slurry pump (5) for discharging mud.
8. A desulfurization absorber slurry treatment method using the system according to any one of claims 1 to 7, comprising the steps of: S1, judging and switching the system, namely switching the desulfurization system to a sedimentation mode by a control system (16) when the desulfurization system is in normal operation and the accident slurry tank (4) is in an idle state; S2, sequencing batch feeding and sedimentation, namely continuously or intermittently introducing partial slurry overflowed from a gypsum cyclone station (7) into an accident slurry tank (4) through a wastewater cyclone station supply pump (12) until the slurry reaches a set liquid level, stopping feeding, and standing and sedimentation for a preset time in the accident slurry tank (4) to separate fine particles from clear liquid; S3, discharging supernatant, namely after sedimentation is finished, opening a supernatant discharge pipe valve by a control system (16), and discharging supernatant to a desulfurization wastewater pre-sedimentation tank (14) until the liquid level in the tank is reduced to a set height; S4, bottom mud recycling treatment, namely closing a supernatant discharge pipe valve, starting a bottom stirring device of an accident slurry tank (4), stirring the settled concentrated bottom mud uniformly, then starting an accident slurry pump (5), and conveying all or part of the bottom mud back to a desulfurization absorption tower (1) to continue to participate in reaction, or conveying the bottom mud to a vacuum belt conveyor (8) to be mixed with underflow of a gypsum cyclone station (7) for dehydration; And S5, after the completion of the step S4, returning to the step S2 to start the next treatment cycle, and if an accident alarming or overhauling instruction is received, immediately switching the accident slurry tank (4) to an emergency mode by the control system (16), and emptying or standing by to receive the accident slurry discharged by the desulfurization absorption tower (1).
9. The method according to claim 8, wherein the settling time is 6-12 hours in step S2, the stirring time is 30-60 minutes in step S4, and the amount of the clear liquid discharged once in step S3 is matched with the treatment amount of one standard treatment cycle of the desulfurization wastewater treatment system (15).
10. The desulfurization absorption tower slurry treatment method according to claim 8, wherein the control system (16) is configured to switch between an emergency mode and a normal sedimentation mode of the accident slurry tank (4) through a man-machine interface.

Description

Desulfurization absorption tower slurry treatment system and method Technical Field The invention belongs to the technical field of flue gas desulfurization treatment of coal-fired power plants, and particularly relates to a slurry treatment system and method for a desulfurization absorption tower, which are suitable for daily optimization treatment and disposal of absorption tower slurry in a wet desulfurization process. Background In a wet flue gas desulfurization system, a desulfurization absorption tower is core equipment for realizing high-efficiency removal of SO 2. However, during actual operation, the absorber may be degraded by various factors such as slurry circulation pump failure, nozzle blockage, uncontrolled pH, insufficient oxidation air volume, or fouling of components within the column. The abnormal working conditions not only can obviously reduce the desulfurization efficiency, but also can cause the problems of slurry foaming in a tower, small growth size of gypsum crystals, incapability of timely discharging tiny insoluble matters such as dust and the like, further influence the quality of desulfurized gypsum and the separation capacity of a wastewater cyclone station, and even force the system to stop when serious, thereby influencing the continuous and stable operation of power plants or industrial devices. To cope with such emergency situations, the configuration of the accident slurry tank is particularly critical. When the absorption tower is abnormal in operation, the slurry in the tower needs to be quickly discharged to an accident slurry tank so as to avoid further deterioration of the slurry quality or equipment damage. The accident slurry tank not only provides buffer capacity for fault treatment, but also can temporarily store unqualified slurry, so that the subsequent repair, replacement or waste treatment is facilitated. However, in actual operation, the accident slurry tank is usually only started during 'emergency storage' and 'system buffering', so that the accident slurry tank is in an idle state for a long time, the utilization rate is low, only a passive function is exerted, the large-volume advantage of the accident slurry tank is not fully utilized to perform daily slurry optimization treatment, and the comprehensive utilization space of the accident slurry tank is limited. In addition, the wastewater cyclone station has poor separation effect on tiny particles (such as chloride ions and tiny dust), so that the quality of the desulfurization wastewater is unstable, and the subsequent treatment efficiency is affected. Therefore, a systematic method is needed to link the accident slurry tank with the main flow process, so as to improve the comprehensive utilization rate of equipment and the solid-liquid separation effect. Disclosure of Invention Aiming at the problems, the invention provides a slurry treatment system and a slurry treatment method for a desulfurization absorption tower, which are used for linking an accident slurry tank with a gypsum dehydration system, switching operation modes by combining an intelligent control system, optimizing operation modes of a gypsum cyclone station and a wastewater cyclone station, strengthening the discharge capacity of toxic substances in slurry and improving the system adjustment flexibility and the equipment use efficiency. The invention comprises a desulfurization absorption tower, a regional slurry pond slurry pump, an accident slurry tank, an accident slurry pump, a gypsum discharge pump, a gypsum cyclone station, a vacuum belt conveyor, a reuse water tank, a reuse water pump, a wastewater cyclone station supply tank, a wastewater cyclone station supply pump, a wastewater cyclone station, a desulfurization wastewater pre-sedimentation tank, a desulfurization wastewater treatment system, a control system and the like, wherein the volume of the accident slurry tank is fully utilized through process optimization and intelligent control, the concentration of chloride ions and tiny particles of discharged desulfurization wastewater is reduced, and the problems of poor effect of separating tiny dust particles in the wastewater cyclone station are solved. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The slurry treatment system of the desulfurization absorption tower comprises a desulfurization absorption tower, a gypsum discharge pump, a gypsum cyclone station, a vacuum belt conveyor, a reuse water tank, a wastewater cyclone station supply box, a wastewater cyclone station supply pump, a wastewater cyclone station, a desulfurization wastewater pre-sedimentation tank, a desulfurization wastewater treatment system and a control system, wherein the treatment system also comprises a partially modified accident slurry tank; The feeding port of the gypsum cyclone station is connected with the slurry discharge end of the desulfurization absorption tower through the gypsum discha