Desulfurization system of thermal power plants

Abstract

This utility model relates to the technical field of desulfurization systems, specifically a desulfurization system for a thermal power plant. It includes a boiler connected to an induced draft fan via a flue, and the induced draft fan connected to an absorption tower via an inlet flue. The absorption tower is connected to a chimney via a flue. A heat exchange tube is installed inside the inlet flue, with a water inlet pipe connected to the inlet and a water outlet pipe connected to the outlet. The bottom of the inlet flue is an inclined plate with one end higher than the other, and the absorption tower is connected to the lower end of the inclined plate. This utility model, by installing heat exchange tubes, can recover and utilize the temperature of the flue gas at the desulfurization tower inlet, eliminating the need for spray cooling and avoiding heat loss, spray water loss, and water vapor loss from the absorption tower.

Description

Technical Field

[0001] This utility model relates to the field of desulfurization system technology, specifically a desulfurization system for thermal power plants. Background Technology

[0002] The flue gas generated by the boilers of thermal power plants needs to be desulfurized by the absorption tower before being discharged. Currently, the inlet flue gas temperature of the desulfurization tower in thermal power plants is generally above 130°C. In summer, when the ambient temperature is high, the inlet flue gas temperature of the desulfurization tower can reach 160°C. The high inlet flue gas temperature of the absorption tower also requires the activation of fire sprinkler cooling, resulting in significant heat loss, sprinkler water loss, and water vapor loss in the absorption tower, which leads to a reduction in the economic efficiency of the unit. Utility Model Content

[0003] The main purpose of this utility model is to provide a desulfurization system for thermal power plants to solve the problem of excessively high flue gas temperature at the inlet of the desulfurization tower in thermal power plants, which causes significant heat loss, spray water loss, and water vapor loss in the absorption tower.

[0004] To achieve the above objectives, this utility model provides a desulfurization system for a thermal power plant, including a boiler, an induced draft fan connected to the boiler via a flue, an absorption tower connected to the induced draft fan via an inlet flue, and a chimney connected to the absorption tower via a flue; a heat exchange tube is installed inside the inlet flue, with a water inlet pipe connected to the inlet of the heat exchange tube and a water outlet pipe connected to the outlet.

[0005] Furthermore, the bottom of the flue gas duct leading to the tower is an inclined plate with one end higher than the other, and the absorption tower is connected to the lower end of the inclined plate.

[0006] Furthermore, a flushing pipe for rinsing the heat exchange tubes is installed inside the flue gas inlet, and the flushing pipe is equipped with nozzles.

[0007] Furthermore, flow meters are installed on both the inlet and outlet pipes.

[0008] Furthermore, a protective layer is provided on the outside of the heat exchange tube, and the material of the protective layer is fluoroplastic or ceramic.

[0009] Furthermore, the inlet pipe is connected to a demineralized water pipe or a condensate pipe, and the outlet pipe is connected to the turbine condensate system.

[0010] This invention, by setting up heat exchange tubes, can recover and utilize the temperature of the flue gas at the inlet of the desulfurization tower, eliminating the need for spray cooling and avoiding problems such as heat loss, spray water loss, and water vapor loss from the absorption tower.

[0011] This invention, by incorporating an inclined plate, allows leaking water to be discharged into the absorption tower under gravity when the heat exchange tube leaks; by incorporating a flushing pipe, the outer side of the heat exchange tube can be flushed to prevent ash accumulation on the tube from affecting heat exchange and to prevent ash accumulation at the bottom of the flue gas duct; by incorporating a flow meter, leaks in the heat exchange tube can be detected promptly by comparing the readings of two flow meters; and by incorporating a protective layer, wear and flue gas corrosion can be effectively reduced.

[0012] This invention connects the outlet pipe to the condensate system, enabling the replenishment of heat-absorbing water to the turbine condensate system, thereby increasing the condensate temperature and reducing steam consumption. Attached Figure Description

[0013] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0014] Figure 1 This is a schematic diagram of the desulfurization system of a thermal power plant in the embodiment; Figure 2 This is a schematic diagram of the structure at the flue gas inlet in the embodiment; In the diagram: 1. Boiler; 2. Exhaust fan; 3. Absorption tower; 4. Inlet flue; 401. Inclined plate; 5. Heat exchange tube; 6. Inlet water pipe; 7. Outlet water pipe; 8. Flushing pipe; 801. Nozzle; 9. Flow meter; 10. Chimney. Detailed Implementation

[0015] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0016] like Figures 1 to 2 As shown in the embodiment of this utility model, a desulfurization system for a thermal power plant is provided, including a boiler 1. The boiler 1 is connected to the inlet of an induced draft fan 2 through a flue. The outlet of the induced draft fan 2 is connected to the inlet of an absorption tower 3 through an inlet flue 4. The absorption tower 3 is connected to a chimney 10 through a flue. A heat exchange tube 5 is installed inside the inlet flue 4. The heat exchange tube 5 is made of stainless steel and is arranged in an S-shape. A water inlet pipe 6 is connected to the inlet of the heat exchange tube 5, and a water outlet pipe 7 is connected to the outlet.

[0017] The bottom of the inlet flue 4 is an inclined plate 401 with a higher left end and a lower right end. The absorption tower 3 is connected to the right end of the inclined plate 401. By setting the inclined plate 401, when the heat exchange tube 5 leaks, the leaked water can be discharged into the absorption tower 3 under the action of gravity. The inner wall of the inlet flue 4 is provided with a glass flake anti-corrosion layer to prevent the condensate in the flue gas from corroding the inlet flue.

[0018] The flue duct 4 is equipped with a flushing pipe 8 for flushing the heat exchange tubes 5. The flushing pipe 8 is equipped with multiple nozzles 801 facing the flushing pipe 8. By setting the flushing pipe 8, the outside of the heat exchange tubes 5 can be flushed to prevent ash accumulation on the heat exchange tubes 5 from affecting heat exchange, and also to prevent ash accumulation at the bottom of the flue duct 4.

[0019] Both the inlet pipe 6 and the outlet pipe 7 are equipped with flow meters 9. By installing flow meters, when the heat exchange tube leaks, the readings of the two flow meters can be compared in time to detect the leak. When the outlet flow rate is less than the inlet flow rate, it indicates that there is a leak in the heat exchange tube.

[0020] In some embodiments, a protective layer is provided on the outside of the heat exchange tube 5. The material of the protective layer is fluoroplastic or ceramic. The protective layer can effectively reduce wear and flue gas corrosion.

[0021] In some embodiments, the inlet pipe 6 is connected to a demineralized water pipe or a condensate pipe, and the outlet pipe 7 is connected to a turbine condensate system; the water that has absorbed heat is added to the turbine condensate system to increase the temperature of the condensate and reduce steam consumption.

[0022] The above embodiment, by setting up heat exchange tubes, can recover and utilize the temperature of the flue gas at the inlet of the desulfurization tower, eliminating the need for spray cooling and avoiding heat loss, spray water loss, and water vapor loss from the absorption tower. After using heat exchange tubes, according to the power system energy saving difference analysis calculation chart, for a 300MW unit boiler, a 10℃ reduction in flue gas temperature can save 1.66g / kWh of coal. Reducing the temperature from 140℃ to 50℃ can save 14.94g / kWh. Based on 300 days of operation per year and an hourly power generation of 280MW, this translates to an annual saving of 30,119.04 tons of coal.

[0023] The above embodiments, by setting up inclined plates, can discharge leaked water into the absorption tower under the action of gravity when the heat exchange tube leaks; by setting up flushing pipes, the outside of the heat exchange tubes can be flushed to prevent ash accumulation on the heat exchange tubes from affecting heat exchange, and also to prevent ash accumulation at the bottom of the flue gas duct; by setting up flow meters, leaks in the heat exchange tubes can be detected in time by comparing the readings of two flow meters; and by setting up a protective layer, wear and flue gas corrosion can be effectively reduced.

[0024] The above embodiments, by connecting the outlet pipe to the condensate system, can replenish the turbine condensate system with water that has absorbed heat, thereby increasing the temperature of the condensate and reducing steam consumption.

[0025] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A desulfurization system for a thermal power plant, comprising a boiler (1), wherein the boiler (1) is connected to an induced draft fan (2) via a flue, the induced draft fan (2) is connected to an absorption tower (3) via an inlet flue (4), and the absorption tower (3) is connected to a chimney (10) via a flue; characterized in that, The inlet flue (4) is equipped with a heat exchange tube (5), and the inlet of the heat exchange tube (5) is connected to a water inlet pipe (6), and the outlet is connected to a water outlet pipe (7).

2. The desulfurization system for thermal power plants as described in claim 1, characterized in that, The bottom of the flue gas duct (4) is an inclined plate (401) with one end higher than the other, and the absorption tower (3) is connected to the lower end of the inclined plate (401).

3. The desulfurization system for thermal power plants as described in claim 2, characterized in that, The inlet flue (4) is provided with a flushing pipe (8) for flushing the heat exchange tube (5), and the flushing pipe (8) is provided with a nozzle (801).

4. The desulfurization system for thermal power plants as described in claim 1, characterized in that, Both the inlet pipe (6) and the outlet pipe (7) are equipped with flow meters (9).

5. The desulfurization system for thermal power plants as described in claim 1, characterized in that, The heat exchange tube (5) is provided with a protective layer on the outside, and the material of the protective layer is fluoroplastic or ceramic.

6. The desulfurization system for thermal power plants as described in claim 1, characterized in that, The inlet pipe (6) is connected to a demineralized water pipe or a condensate pipe, and the outlet pipe (7) is connected to a turbine condensate system.

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