Boiler blowdown recovery system

Abstract

The utility model discloses a boiler blowdown recovery system which comprises a boiler drum, a deaerator, a demineralized water tank, a steam separator and a softened water treatment device, a fixed discharge pipeline and a continuous discharge pipeline of the boiler drum are connected with the steam separator, a steam output pipeline of the steam separator is communicated with a steam liquefying device, the steam liquefying device is communicated to the deaerator, and the demineralized water tank is communicated with the deaerator. A high-temperature water output pipeline of the steam separator is communicated with a softened water treatment device, the softened water treatment device is connected with a demineralized water tank, the demineralized water tank is communicated to a deaerator, and the deaerator is communicated with a boiler drum. According to the boiler blow-off water recovery system, waste of heat energy and water resources in the boiler blow-off period is reduced, and meanwhile a boiler blow-off water softening system is simplified.

Description

Technical Field

[0001] The utility model relates to the technical field of boiler blowdown systems, and particularly to a boiler blowdown recovery system. Background Art

[0002] Boilers play a crucial role in industrial production and are widely used in heating, steam power drive, heat supply, etc. Industries such as chemical industry, textile, paper making, and food processing rely on the high-temperature heat energy provided by boilers to complete process operations such as heating, evaporation, and drying.

[0003] During the boiler production process, pollutants such as metal ions and particulate matter often exist in the circulating water system, causing equipment corrosion, valve blockage, reducing equipment life, and even triggering system failures. Therefore, blowdown treatment is often required. The blowdown forms are divided into continuous blowdown and regular blowdown. Continuous blowdown mainly removes the surface layer of boiler water to reduce the salt content and alkalinity to maintain steam quality; regular blowdown removes the water slag and soft precipitates accumulated at the bottom to reduce corrosion and blockage of equipment. Through these two blowdown methods, the cleanliness of the circulating water system can be effectively maintained, the equipment life can be extended, and the safe and stable operation of the boiler system can be ensured.

[0004] Conventional boiler blowdown systems directly discharge the regular blowdown and continuous blowdown into the environment, resulting in waste of heat energy and water resources. Currently, an existing recovery technology is to separate steam and high-temperature water from boiler blowdown using a flash tank, and the high-pressure steam is led to the deaerator for heating and deaeration, while the high-temperature water is directly discharged into the trench.

[0005] This recovery method recovers the high-pressure steam during both regular blowdown and continuous blowdown. Due to the large amount of regular blowdown, introducing the recovered saturated steam into the deaerator will cause unstable operating conditions of the deaerator and is not conducive to the stable operation of the system.

[0006] What is discharged into the trench is high-temperature water, and direct discharge will cause waste of heat energy and water resources. Currently, an existing technology is to use a heat exchanger for heat recovery. However, due to the limited heat transfer effect of the plate heat exchanger, most of the heat energy is still discharged into the trench in the form of sewage. In addition, the sewage contains a large amount of contaminants, and the heat transfer method using a plate heat exchanger is prone to sediment blockage.

[0007] For the hard water discharged into the trench, it is often treated into softened water by an industrial sewage treatment station and then returned to the deaerator and added to the boiler circulating water system through a feed water pump. Compared with other industrial wastewaters, the sewage components of boiler blowdown are relatively simple, mainly to remove the precipitates and metal ions such as calcium and magnesium in the blowdown. The treatment method of discharging to the sewage treatment station brings great treatment pressure to the sewage treatment station. Content of the Utility Model

[0008] To solve the above technical problems, the utility model designs a boiler blowdown recovery system.

[0009] The utility model adopts the following technical scheme:

[0010] A boiler blowdown recovery system includes a boiler steam drum, a deaerator, a demineralized water tank, a steam separator and a soft water treatment device. The regular blowdown pipeline, continuous blowdown pipeline of the boiler steam drum are connected to the steam separator. The steam output pipeline of the steam separator is communicated with a steam liquefaction device, and the steam liquefaction device is communicated to the deaerator. The high-temperature water output pipeline of the steam separator is communicated with the soft water treatment device, the soft water treatment device is connected to the demineralized water tank, the demineralized water tank is communicated to the deaerator, and the deaerator is communicated with the boiler steam drum.

[0011] Preferably, the soft water treatment device includes a pump body, a pre-sedimentation tank, a reaction tank, a PH adjustment tank connected in series through pipelines in sequence. A chemical agent tank is connected to the reaction tank, and control valves are installed on each connecting pipeline of the reaction tank.

[0012] Preferably, partition plates arranged alternately up and down are provided in the pre-sedimentation tank.

[0013] Preferably, a stirring device is arranged in the reaction tank.

[0014] Preferably, the demineralized water tank is connected with a soft water make-up pipeline.

[0015] Preferably, the deaerator is connected with a low-pressure steam inlet pipeline.

[0016] Preferably, a circulation pump is installed on the pipeline between the steam separator and the deaerator.

[0017] Preferably, a return water pump is installed on the pipeline between the demineralized water tank and the deaerator.

[0018] Preferably, a feed water pump is installed on the pipeline between the boiler steam drum and the deaerator.

[0019] The beneficial effect of the utility model is that the utility model designs a boiler blowdown recovery system, which reduces the waste of heat energy and water resources during boiler blowdown, and simplifies the boiler blowdown water softening system at the same time. Description of the Drawings

[0020] Figure 1 is a structural schematic diagram of the utility model;

[0021] Figure 2 is a structural schematic diagram of the soft water processor in the utility model;

[0022] In the figure: 1. Boiler steam drum, 2. Deaerator, 3. Demineralized water tank, 4. Steam separator, 5. Soft water treatment device, 6. Steam liquefaction device, 7. Regular blowdown pipeline, 8. Continuous blowdown pipeline, 9. Steam, 10. High-temperature water, 11. Soft water make-up pipeline, 12. Low-pressure steam inlet pipeline, 13. Circulation pump, 14. Return pump, 15. Feed pump, 51. Pump body, 52. Preliminary sedimentation tank, 53. Reaction tank, 54. PH adjustment tank, 55. Chemical tank, 56. Baffle, 57. Stirring device, 58. Control valve. Detailed implementation mode

[0023] The technical solution of the present utility model will be further specifically described below through specific embodiments in conjunction with the drawings:

[0024] Embodiment: As Figure 1 shown, a boiler blowdown recovery system includes a boiler steam drum 1, a deaerator 2, a demineralized water tank 3, a steam separator 4 and a soft water treatment device 5. The regular blowdown pipeline 7 and the continuous blowdown pipeline 8 of the boiler steam drum are connected to the steam separator. The steam output pipeline of the steam separator is communicated with the steam liquefaction device 6, and the steam liquefaction device is communicated to the deaerator. The high-temperature water output pipeline of the steam separator is communicated with the soft water treatment device, the soft water treatment device is connected to the demineralized water tank, the demineralized water tank is communicated to the deaerator, and the deaerator is communicated with the boiler steam drum.

[0025] The demineralized water tank is connected with a soft water make-up pipeline 11. The deaerator is connected with a low-pressure steam inlet pipeline 12. A circulation pump 13 is installed on the pipeline between the steam separator and the deaerator. A return pump 14 is installed on the pipeline between the demineralized water tank and the deaerator. A feed pump 15 is installed on the pipeline between the boiler steam drum and the deaerator.

[0026] The steam separator separates the steam 9 from the high-temperature water 10, and the separated steam is led to a steam trap for liquefaction. The liquefied saturated water is led to the deaerator through a circulation pump; the high-temperature water (hard water) enters the soft water treatment device, and the soft water treated by the soft water treatment device is introduced into the demineralized water tank; the water in the deaerator is pumped back into the steam drum through a feed pump.

[0027] As Figure 2 shown, the soft water treatment device includes a pump body 51, a preliminary sedimentation tank 52, a reaction tank 53, and a PH adjustment tank 54 connected in series through pipelines in sequence. A chemical tank 55 is connected to the reaction tank, and control valves 58 are installed on each connecting pipeline of the reaction tank. The preliminary sedimentation tank is provided with baffles 56 arranged alternately up and down. A stirring device 57 is arranged in the reaction tank.

[0028] First, the sewage to be discharged is pumped into a pre-sedimentation tank for preliminary filtration and sedimentation treatment to remove solid particles and sediments therein. Specifically, there are partition plates arranged alternately up and down in the pre-sedimentation tank, which is conducive to the settlement of solid particles and sediments. The sewage after pre-sedimentation enters the reaction tank, and a chemical softening agent is added to the sewage to be discharged. Commonly used softening agents include phosphates such as trisodium phosphate and soda ash such as sodium hydroxide. The softening agent can chemically react with calcium and magnesium ions in the water to form precipitates or soluble salts, thereby reducing the hardness of the water. A stirring device is provided in the reaction tank to fully mix the softening agent with the sewage to be discharged evenly, prompting the softening agent to fully react with calcium and magnesium ions in the water to achieve water softening. After the softening agent reacts with calcium and magnesium ions in the water to form precipitates or soluble salts, the precipitates are separated from the water by methods such as precipitation or filtration, thereby achieving water softening; according to the quality of the softened water, the pH value of the water can be further adjusted in the pH adjustment tank to ensure that the quality of the softened water meets the usage requirements.

[0029] The above-described embodiments are only a preferred solution of the present invention and do not impose any form of limitation on the present invention. There are other variants and modifications without exceeding the technical solutions recorded in the claims.

Claims

1. A boiler wastewater recovery system, characterized in that: It includes a boiler drum, a deaerator, a desalted water tank, a steam separator and a softened water treatment device. The fixed row pipeline and the continuous row pipeline of the boiler drum are connected to the steam separator. The steam output pipeline of the steam separator is connected to the steam liquefaction device, the steam liquefaction device is connected to the deaerator, the high-temperature water output pipeline of the steam separator is connected to the softened water treatment device, the softened water treatment device is connected to the desalted water tank, the desalted water tank is connected to the deaerator, and the deaerator is connected to the boiler drum.

2. A boiler wastewater recovery system according to claim 1, characterized in that: The softened water treatment device comprises a pump body, a pre-precipitation tank, a reaction tank, and a pH adjustment tank which are sequentially connected in series through pipelines. The reaction tank is connected to a reagent box, and control valves are installed on each connecting pipeline of the reaction tank.

3. A boiler wastewater recovery system according to claim 2, characterized in that: The pre-precipitation tank is provided with partitions which are alternately arranged up and down.

4. A boiler wastewater recovery system according to claim 2, characterized in that: A stirring device is arranged in the reaction tank.

5. A boiler wastewater recovery system according to claim 1, characterized in that: The demineralized water tank is connected with a softened water replenishment pipeline.

6. A boiler wastewater recovery system according to claim 1, characterized in that: The deaerator is connected with a low-pressure steam inlet pipeline.

7. A boiler wastewater recovery system according to claim 1, characterized in that: A circulating pump is installed on the pipeline between the steam separator and the deaerator.

8. A boiler wastewater recovery system according to claim 1, characterized in that: A return water pump is installed on the pipeline between the desalted water tank and the deaerator.

9. A boiler wastewater recovery system according to claim 1, characterized in that: A feed water pump is installed on the pipeline between the boiler drum and the deaerator.

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