Waste heat boiler feed water dissolved oxygen control system

Abstract

The utility model discloses a waste heat boiler feed water dissolved oxygen control system which comprises a demineralized water supply pipeline connected with the liquid inlet end of a deaerator, the liquid outlet end of the deaerator is communicated with a boiler feed pump through a feed pump inlet pipeline, and the side portion of the feed pump inlet pipeline is connected with a condensed water recovery pipeline. The utility model relates to the technical field of waste heat boiler deoxidization, the contact between demineralized water and oxygen molecules in air is blocked by utilizing a closed space, a deoxidant adding pipeline is connected to an inlet pipeline of a water feeding pump, and the deoxidant adding pipeline is communicated with a condensate pump of a waste heat boiler body. The recycled and condensed low-oxygen-content and high-temperature condensed water is directly conveyed into an inlet pipeline of the water feeding pump, the dissolution rate of a deoxidant is increased by utilizing the temperature of the condensed water, dissolved oxygen in water is rapidly reduced, ferric oxide in water is decomposed, and the deoxidizing effect is improved; the dissolved deoxygenated water is conveyed into the waste heat boiler through a boiler water feeding pump, and the oxygen content in water fed by the waste heat boiler is effectively controlled.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat boiler deoxygenation, in particular to a waste heat boiler feed water dissolved oxygen control system. Background Art

[0002] Oxygen corrosion is the most common and serious corrosion in boiler systems. Since feed water is generally in contact with the atmosphere, the dissolved oxygen in the water is basically saturated, so the pipes and equipment through which the feed water flows are likely to be corroded by oxygen. In the boiler feed water treatment process, deoxygenation is a very critical link. Oxygen is the main corrosive substance in the boiler feed water system. The oxygen in the feed water system should be removed quickly, otherwise it will corrode the boiler's feed water system and components. The corrosive substance iron oxide will enter the boiler and deposit or adhere to the boiler tube wall and heating surface, forming iron scale that is difficult to dissolve and has poor heat transfer. The corroded iron scale will cause pits on the inner wall of the pipe, causing the boiler resistance coefficient to increase. In view of this, in-depth research on the above-mentioned issues led to this case. Utility Model Content

[0003] In view of the deficiencies in the prior art, the utility model provides a waste heat boiler feed water dissolved oxygen control system, which solves the problems raised in the background technology.

[0004] To achieve the above objectives, the utility model is implemented through the following technical solutions: a waste heat boiler feed water dissolved oxygen control system, including a desalted water supply pipe connected to the liquid inlet end of the deaerator, the liquid outlet end of the deaerator is connected to the boiler feed water pump through a feed water pump inlet pipe, a condensate recovery pipe is connected to the side of the feed water pump inlet pipe, the condensate recovery pipe is connected to the condensate pump at one end of the condenser on the waste heat boiler body, a deoxidizer addition pipe is connected to one side of the feed water pump inlet pipe, and the deoxidizer addition pipe is connected to the deoxidizer dissolution tank through the deoxidizer addition pump.

[0005] Preferably, a main flow regulating valve is provided on the desalted water supply pipeline.

[0006] Preferably, the condensate recovery pipeline is provided with a first flow regulating valve and a first one-way valve, and the conducting direction of the first one-way valve points to the side of the water feed pump inlet pipeline.

[0007] Preferably, a second flow regulating valve and a second one-way valve are provided on the deoxidizer addition pipeline, and the conducting direction of the second one-way valve points to the side of the water pump inlet pipeline.

[0008] Preferably, an online oxygen concentration monitoring device is installed on the feed water pump inlet pipe near the boiler feed water pump.

[0009] The utility model provides a waste heat boiler feed water dissolved oxygen control system. It has the following beneficial effects: the waste heat boiler feed water dissolved oxygen control system uses a closed space to block the contact between desalted water and oxygen molecules in the air, connects a deoxidizer addition pipeline at the feed water pump inlet pipeline, and directly transports the recovered condensed low oxygen content and high temperature condensate to the feed water pump inlet pipeline, uses its temperature to increase the deoxidizer dissolution rate, quickly reduces the dissolved oxygen in the water, decomposes the iron oxide in the water, improves the deoxidation effect, and the position of the deoxidizer dissolution box can be installed according to the environment; the dissolved deoxidized water is transported to the waste heat boiler by the boiler feed water pump, effectively controls the oxygen content in the waste heat boiler feed water, curbs equipment corrosion, and removes oxygen and prevents scaling. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram of the main structure of the waste heat boiler feed water dissolved oxygen control system of the utility model.

[0011] In the figure: 1. Deaerator; 2. Desalted water supply pipeline; 3. Feed water pump inlet pipeline; 4. Boiler feed water pump; 5. Condensate recovery pipeline; 6. Waste heat boiler body; 7. Condensate pump; 8. Deoxidizer addition pipeline; 9. Deoxidizer addition pump; 10. Deoxidizer dissolution tank; 11. Main flow regulating valve; 12. First flow regulating valve; 13. First non-return valve; 14. Second flow regulating valve; 15. Second non-return valve; 16. Oxygen concentration online monitoring equipment. DETAILED DESCRIPTION

[0012] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0013] Embodiment: In conjunction with the specification Figure 1It can be seen that in order to solve the problem of high oxygen content in the waste heat boiler feed water system in the prior art, which is easy to cause corrosion of the boiler feed water system and components, the present application specifically designs a waste heat boiler feed water dissolved oxygen control system, including a desalted water supply pipeline 2 connected to the liquid inlet end of the deaerator 1, the liquid outlet end of the deaerator 1 is connected to the boiler feed water pump 4 through the feed water pump inlet pipeline 3, and the side of the feed water pump inlet pipeline 3 is connected to a condensate recovery pipeline 5, and the condensate recovery pipeline 5 is connected to the condensate pump 7 at one end of the condenser on the waste heat boiler body 6, and the feed water pump inlet pipeline 3 is connected to the condensate recovery pipeline 5. One side of the pipeline 3 is connected to a deoxidizer adding pipeline 8, which is connected to a deoxidizer dissolving tank 10 through a deoxidizer adding pump 9. The deoxidized water in the deoxidized water supply pipeline 2 first passes through a deoxidizer 1 for deep deoxidation, and a closed space is used to block the deoxidized water from contacting with oxygen molecules in the air. At the same time, the deoxidizer adding pipeline 8 is connected to the water supply pump inlet pipeline 3, and the recovered condensed low-oxygen and high-temperature condensed water is directly transported to the water supply pump inlet pipeline 3, and its temperature is used to increase the deoxidizer dissolution rate, quickly reduce the dissolved oxygen in the water, and decompose the water. Iron oxide is formed in the waste heat boiler to improve the deoxidation effect; the dissolved deoxidized water is transported to the waste heat boiler by the boiler feed pump 4, and the deaerator 1 is completely sealed, so that the desalted water, condensate and deoxidizer are directly mixed at high temperature in the transportation pipeline, dissolved in advance, and oxygen molecules in the air are isolated. The deoxidation effect is significant, which can ensure the safe, efficient and economical operation of the waste heat boiler, reduce the boiler maintenance cost, and extend the service life of the boiler. When the condenser on the waste heat boiler body 6 is put into operation, the low-oxygen condensate produced is supplied to the condensate pump 7 and the condensate recovery pipeline 5. The feed water pump inlet pipe 3 is connected to the deoxidizer dissolving tank 10 through the deoxidizer adding pipe 8, so that the condensate with low oxygen content in the condenser is recovered and directly transported to the boiler feed water, and mixed with a small amount of deoxidizer added in the pipe, without contacting with oxygen molecules in the air throughout the process. The low oxygen content and high temperature condensate is used to increase the temperature of the desalted water, so that the deoxidizer can fully react and dissolve in advance, and quickly decompose the iron oxide in the water. In this system, the condenser is equivalent to a vacuum deoxidizer 1, which reduces the oxygen content of the condensate, and the position of the deoxidizer dissolving tank 10 can be installed according to the environment. The dissolved deoxidized water is transported to the boiler by the boiler feed water pump 4, which effectively controls the oxygen content in the waste heat boiler feed water, curbs equipment corrosion, removes oxygen and prevents scale, and achieves the effect of reducing dissolved oxygen and alleviating equipment corrosion.

[0014] In the specific implementation process, as a preferred setting, a main flow regulating valve 11 is provided on the above-mentioned desalted water supply pipeline 2; wherein a first flow regulating valve 12 and a first non-return valve 13 are provided on the condensate recovery pipeline 5, and the conduction direction of the first non-return valve 13 points to the side of the feed water pump inlet pipeline 3; a second flow regulating valve 14 and a second non-return valve 15 are provided on the above-mentioned deoxidizer addition pipeline 8, and the conduction direction of the second non-return valve 15 points to the side of the feed water pump inlet pipeline 3; an oxygen concentration online monitoring device 16 is installed on the above-mentioned feed water pump inlet pipeline 3 near the boiler feed water pump 4. When in use, the main flow regulating valve 11 is used to adjust the supply amount of desalted water, and according to the detection result of the oxygen concentration online monitoring device 16, the first flow regulating valve 12 and the second flow regulating valve 14 are used to adjust the supply of condensed water and deoxidizer respectively, thereby preferably reducing the oxygen content in the water. It has a simple structure and a high degree of automation.

[0015] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Waste heat boiler feed water dissolved oxygen control system, characterized in that: It includes a desalted water supply pipeline connected to the liquid inlet end of the deaerator, the liquid outlet end of the deaerator is connected to the boiler feed water pump through the feed water pump inlet pipeline, the side of the feed water pump inlet pipeline is connected to a condensate recovery pipeline, the condensate recovery pipeline is connected to the condensate pump at one end of the condenser on the waste heat boiler body, the feed water pump inlet pipeline is connected to a deoxidizer addition pipeline on one side, and the deoxidizer addition pipeline is connected to the deoxidizer dissolution tank through the deoxidizer addition pump.

2. The waste heat boiler feed water dissolved oxygen control system according to claim 1, characterized in that: The desalted water supply pipeline is provided with a main flow regulating valve.

3. The waste heat boiler feed water dissolved oxygen control system according to claim 1, characterized in that: The condensate recovery pipeline is provided with a first flow regulating valve and a first one-way valve, and the conducting direction of the first one-way valve points to the side of the water feed pump inlet pipeline.

4. The waste heat boiler feed water dissolved oxygen control system according to claim 1, characterized in that: The deoxidizer adding pipeline is provided with a second flow regulating valve and a second one-way valve, and the conducting direction of the second one-way valve points to the side of the water supply pump inlet pipeline.

5. The waste heat boiler feed water dissolved oxygen control system according to claim 1, characterized in that: An oxygen concentration online monitoring device is installed on the feed water pump inlet pipe near the boiler feed water pump.

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