An online dredging device for oxidation air duct of desulfurization tower

Abstract

The utility model provides an online dredging device for oxidation air duct of a desulfurization tower, including: an oxidation fan; a desulfurization tower; a limestone slurry replenishing pipe; a circulating slurry pump; an oxidation air main pipe, one end of which is connected to the oxidation fan outlet, and the oxidation air main pipe has a cooling water location with a dredging port; an oxidation air branch pipe, which is arranged between the other end of the oxidation air main pipe and the oxidation air inlet; and a flange, which is arranged above the dredging port; wherein; the oxidation fan outlet, the oxidation branch pipe and the cooling water location are respectively provided with a first stop valve, a second stop valve and a third stop valve. The utility model prepares environmental protection operation measures and maintenance measures in advance without affecting the operation of the host and the desulfurization system and the environmental protection emission standards. It only needs to suspend the oxidation air system (about 1 hour) to realize the online rapid manual cleaning of the blockage at the dry-wet junction of the cooling water of the oxidation air main pipe, and quickly restore the oxidation air volume and air pressure, thereby improving the desulfurization efficiency.

Description

Technical Field

[0001] The utility model relates to the field of power desulfurization, in particular to an online dredging device for oxidation air ducts of a desulfurization tower. Background Art

[0002] The function of the limestone-gypsum wet flue gas desulfurization oxidation air system of coal-fired units is to oxidize calcium sulfite in the desulfurization slurry into calcium sulfate. On the one hand, it can ensure the continuous process of absorbing sulfur dioxide, improve the desulfurization efficiency, and at the same time improve the quality of the desulfurization byproduct gypsum; on the other hand, it can prevent calcium sulfite from scaling in the gypsum slurry pipeline. The air required for the oxidation of the absorption tower slurry is forced by the oxidation fan. The oxidation fan compresses the air and outputs it at a large flow rate. The fan outlet temperature is about 100°C. The compressed air needs to be cooled by cooling water before being blown into the absorption tower. The cooling water of the oxidation air mother pipe is a dry-wet junction. The cooling water is process water with a high hardness and contains a large amount of calcium and magnesium ions. After long-term operation, a large amount of hard scale will accumulate at the cooling water. The hard scale will reduce the inner diameter of the pipeline and reduce the oxidation air volume and air pressure. After the oxidation air volume is reduced, the oxidation effect of the absorption tower slurry is poor, the desulfurization efficiency is low, and the gypsum is not conducive to dehydration. In order to improve the desulfurization efficiency and ensure that environmental protection standards are met, the amount of limestone slurry is increased during operation, the number of circulating pumps is increased, the scaling of the desulfurization system is increased, and the operation and maintenance costs of the desulfurization system are increased.

[0003] The purpose of the utility model is to provide an online unclogging device for the oxidation air duct of a desulfurization tower. When the oxidation air duct is unblocked online, it will not affect the operation of the main engine and the desulfurization system. Environmental protection operation measures and maintenance measures must be taken in advance. During the online unclogging, the oxidation air system must be suspended (for about 1 hour), and the blockage at the dry and wet junction of the cooling water of the oxidation air main pipe must be quickly cleaned manually to restore the oxidation air volume and air pressure, thereby improving the oxidation effect of the absorption tower and the desulfurization efficiency. Utility Model Content

[0004] The purpose of the utility model is to provide an online dredging device for the oxidation air duct of a desulfurization tower in view of the above problems.

[0005] The purpose of the utility model is achieved as follows: an online dredging device for an oxidation air duct of a desulfurization tower, comprising: an oxidation fan, a desulfurization tower, a limestone slurry replenishing pipe, a circulating slurry pump, an oxidation air main pipe, an oxidation air branch pipe, a flange, a first stop valve, a second stop valve and a third stop valve, the outlet of the oxidation fan is connected to the oxidation air main pipe, a dredging port is provided on the oxidation air main pipe at a distance of 10-20 cm from a cooling water inlet, a flange is provided above the dredging port, the other end of the oxidation air main pipe is connected to an oxidation air branch pipe, a total of 4-6 oxidation air branch pipes, the oxidation air branch pipe is connected to the oxidation air inlet of the desulfurization tower, the slurry inlet of the desulfurization tower is connected to a limestone slurry replenishing pipe, a circulating slurry pump is provided on the limestone slurry replenishing pipe, a first stop valve is provided at the outlet of the oxidation fan, a second stop valve is provided on each of the oxidation air branch pipes, and a third stop valve is provided at the cooling water.

[0006] A flange is welded on the dredging port, and a sight glass is hinged on the flange.

[0007] The flange diameter is 200-250mm.

[0008] The dredging port is located on the upper surface of the oxidation air main pipe.

[0009] The beneficial effects of the utility model are: 1) it does not affect the operation of the main engine and the environmental protection system, and the blockage of the desulfurization oxidation air duct can be unblocked online; 2) the time consumption of unblocking the blockage online is short, the unblocking is convenient, the oxidation air volume is quickly restored, and the desulfurization efficiency is significantly improved; 3) during the unblocking of the oxidation air duct, the sulfur dioxide emission is within a controllable range; 4) the oxidation air duct flange is equipped with a perspective mirror, and the operating personnel can observe the blockage of the air duct with the naked eye, unblock it in time, and avoid a large number of blockages that reduce the oxidation air volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The utility model is further described below in conjunction with the accompanying drawings.

[0011] Figure 1 It is a structural schematic diagram of the utility model.

[0012] Among them: 1. Oxidation fan, 2. Desulfurization tower, 3. Limestone slurry replenishing pipe, 4. Circulating slurry pump, 5. Oxidation air main pipe, 6. Oxidation air branch pipe, 7. Flange, 8. Sight glass, 9. First stop valve, 10. Cooling water inlet, 11. Third stop valve, 12. Second stop valve, 13. Limestone slurry. DETAILED DESCRIPTION

[0013] The function of the limestone-gypsum wet desulfurization oxidation fan is to force the desulfurization tower to provide air with a certain pressure and flow rate, in order to oxidize the calcium sulfite in the desulfurization tower slurry into calcium sulfate. However, the outlet temperature of the oxidation fan is relatively high (about 100°C). At the oxidation air main pipe of the absorption tower, cooling water is sprayed into the air duct through an atomizing nozzle to reduce the air temperature to 30-40°C before being blown into the desulfurization tower slurry pool.

[0014] Since the desulfurization tower oxidation air cooling water has high hardness and high air temperature, and the oxidation air main pipe cooling water is a high-temperature dry-wet interface, scale will appear during long-term operation, clogging the air duct and nozzle, reducing the oxidation air volume and air temperature, and causing the desulfurization tower slurry to flow back and clog the small holes in the oxidation air duct in the absorption tower, resulting in poor oxidation effect of the desulfurization slurry, hindered absorption of SO2 gas, reduced desulfurization efficiency, and environmental emissions that are likely to exceed standards.

[0015] When this device is implemented, the main engine and the desulfurization system do not need to be shut down, and the blockage in the oxidation air duct of the desulfurization tower can be unblocked online; this device takes a short time to deal with the blockage in the desulfurization tower, and the unblocking is convenient, and the sulfur dioxide emission is within a controllable range; by welding a flange with a perspective mirror at the cooling water where the oxidation air main pipe of the desulfurization tower is easily blocked, the inspection personnel can observe the blockage of the oxidation air duct with the naked eye during operation, and unblock it in time.

[0016] During daily operation, operators can observe the degree of blockage inside the air duct through the perspective mirror connected to the oxidation air duct, and clear it in time to avoid a large number of blockages affecting the desulfurization efficiency. When the blockage of the oxidation air duct of the desulfurization tower is cleared online, the slurry will not flow back to the oxidation air duct. The desulfurization system operates stably and environmental emissions are controllable. After the blockage of the oxidation air duct of the desulfurization tower is cleared online, the oxidation air volume of the desulfurization tower can be quickly restored, and the desulfurization efficiency is significantly improved.

[0017] The technical solution of the utility model is as follows: an online dredging device for oxidation air duct of a desulfurization tower, comprising: an oxidation fan; a desulfurization tower, on which an oxidation air inlet and a slurry inlet are arranged; a limestone slurry replenishing pipe, which is connected to the slurry inlet; a circulating slurry pump, which is arranged on the limestone slurry replenishing pipe; an oxidation air main pipe, one end of which is connected to the oxidation fan outlet, and the oxidation air main pipe has a cooling water place, and the cooling water place is provided with a dredging port; an oxidation air branch pipe, which is arranged between the other end of the oxidation air main pipe and the oxidation air inlet; and a flange, which is arranged above the dredging port; wherein; the oxidation fan outlet, the oxidation branch pipe and the cooling water place are respectively provided with a first stop valve, a second stop valve and a third stop valve.

[0018] In the online dredging device for the oxidation air duct of the desulfurization tower, the flange is welded on the dredging port; and a peephole is provided on the flange.

[0019] In the online dredging device for the oxidation air duct of the desulfurization tower, the diameter of the flange is 200 mm.

[0020] In the online dredging device for the oxidation air duct of the desulfurization tower, the dredging port is located on the upper surface of the oxidation air main pipe.

[0021] In the online dredging device for the oxidation air duct of the desulfurization tower, the lower surface of the oxidation air main pipe corresponding to the dredging port is a collecting port, and a peephole is hinged on the collecting port.

[0022] In the online dredging device for the oxidation air duct of the desulfurization tower, the sight glass is hinged to the flange.

[0023] The utility model can stop the oxidation fan for a short time, quickly clear the blockage of the oxidation air duct online, restore the oxidation air volume and air pressure, and improve the desulfurization efficiency without affecting the operation of the main engine and the desulfurization system and the environmental protection emission standards. The specific implementation process is as follows: 1. Replace the coal entering the boiler with low-sulfur coal 12 hours in advance, control the sulfur content of the original flue gas of the desulfurization to operate at the lower limit, and reduce the load of the main unit to 50%. 2. Take safety measures in advance for maintenance, weld a DN200 flange above the blockage of the oxidation air main pipe, and the welding process is full welding. 3. The desulfurization operation personnel add synergist to the absorption tower in advance to accelerate the decomposition rate of limestone; increase the number of running circulating pumps in the desulfurization tower; add a large amount of limestone slurry to the desulfurization tower in advance to increase the pH value of the absorption tower. The above measures ensure that the outlet SO2 concentration is controlled at the lowest level. 4. After the preparation work is completed, stop the oxidation fan, close the oxidation air branch valve, cut the welded flange, and quickly clear the blockage of the oxidation air duct. 5. After the dredging is completed, repair and restore the flange cover, start the oxidation fan, and restore the oxidation air system. 6. The flange cover uses a perspective mirror cover for the operator to check the air duct blockage online and deal with it in time.

[0024] Although the implementation scheme of the utility model has been disclosed as above, it is not limited to the applications listed in the specification and implementation scheme. It can be fully applied to various fields suitable for the utility model. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the utility model is not limited to specific details.

[0025] The above description is only a specific embodiment of the present invention, but the structural features of the protection scope of the present invention are not limited thereto. Any changes or modifications made by any technician in the field of the present invention are included in the patent scope of the present invention.

Claims

1. An online dredging device for oxidation air duct of a desulfurization tower, characterized in that: include: Oxidation fan, desulfurization tower, limestone slurry replenishing pipe, circulating slurry pump, oxidation air main pipe, oxidation air branch pipe, flange, first stop valve, second stop valve and third stop valve, the outlet of the oxidation fan is connected to the oxidation air main pipe, a dredging port is provided on the oxidation air main pipe at a distance of 10-20 cm from the cooling water inlet, a flange is provided above the dredging port, the other end of the oxidation air main pipe is connected to the oxidation air branch pipe, there are 4-6 oxidation air branch pipes in total, the oxidation air branch pipe is connected to the oxidation air inlet of the desulfurization tower, the slurry inlet of the desulfurization tower is connected to the limestone slurry replenishing pipe, a circulating slurry pump is provided on the limestone slurry replenishing pipe, the outlet of the oxidation fan is provided with a first stop valve, the oxidation air branch pipes are provided with a second stop valve, and the cooling water inlet is provided with a third stop valve.

2. The online dredging device for oxidation air duct of a desulfurization tower according to claim 1 is characterized in that: A flange is welded on the dredging port, and a sight glass is hinged on the flange.

3. The online dredging device for oxidation air duct of a desulfurization tower according to claim 1 is characterized in that: The flange diameter is 200-250mm.

4. The online dredging device for oxidation air duct of a desulfurization tower according to claim 1 is characterized in that: The dredging port is located on the upper surface of the oxidation air main pipe.

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