Boiler water supply structure

Abstract

The utility model relates to the technical field of boiler water supply, in particular to a boiler water supply structure. In order to solve the problem that according to an existing method for guaranteeing stable operation of the boiler water supply structure by arranging a backflow valve on a water supply pipeline, water supply of a waste heat boiler is prone to being cut off, the novel boiler water supply structure comprises an online water supply pipeline, a water conveying pipeline, a heat exchanger, a steam pocket, the waste heat boiler and a controller. The online water supply pipeline is provided with an online water supply pump and an online pressure gauge, the online water supply pump is provided with an online variable frequency motor, the input end of the controller is connected with the online pressure gauge, and the output end of the controller is used for controlling the rotation frequency of the online variable frequency motor. According to the utility model, the load of the on-line feed pump can be adjusted at any time, the operation pressure is reduced, the power consumption is saved, and the conditions of boiler water leakage or waste heat boiler water break caused by overpressure can be effectively prevented, so that the stable operation of a boiler water supply structure is stabilized.

Description

Technical Field

[0001] The utility model relates to the technical field of boiler water supply, in particular to a boiler water supply structure. Background Technique

[0002] Coke gas is a by-product of the coking industry, and its main components are oxygen and methane. The technology of producing LNG from coke oven gas makes the components in coke oven gas be effectively utilized, greatly improves the energy utilization rate, and also reduces environmental pollution. During the methanation reaction of coke oven gas, a large amount of heat is released. To improve the energy utilization rate, the heat generated needs to be recovered to produce steam. Part of the produced steam is used for the methanation reaction, and the remaining can be used for other production.

[0003] The boiler water supply structure adopted when producing steam mainly includes a water supply pipeline, a water delivery pipeline, a heat exchanger, a steam drum, and a waste heat boiler. A water supply pump is arranged on the water supply pipeline. The water supply pump pressurizes the boiler water and then heats the boiler water through the heat exchanger, and then sends the heated boiler water to the steam drum through the water delivery pipeline. The boiler water in the steam drum flows into the waste heat boiler by gravity and then enters the steam drum after being heated by the waste heat boiler to form steam and then is discharged. The heat source of the waste heat boiler is the direct heat generated by the methanation reaction of coke oven gas, and its heat temperature is about 500°C. The heat source of the heat exchanger is also the heat generated by the methanation reaction of coke oven gas, but its heat is the remaining heat after heat exchange through the waste heat boiler and other equipment, and its heat temperature is about 100°C.

[0004] Since the production process of the methanation reaction of coke oven gas has a high continuity and a large energy loss after abnormal shutdown, it is crucial to ensure the stable operation of the boiler water supply structure. Due to the large fluctuation of the production load of the methanation reaction of coke oven gas, the amount of reaction heat generated fluctuates accordingly. To ensure the stable operation of the boiler water supply structure, the existing solution is to set a reflux valve on the water supply pipeline. However, due to the excessive back pressure before and after the reflux valve, erosion and wear are likely to occur during long-term operation, resulting in excessive internal leakage of the reflux valve. Coupled with the large production load, it is easy to cause water cut-off in the waste heat boiler, resulting in dry burning of the waste heat boiler, and in severe cases, an explosion accident of the waste heat boiler may occur. Summary of the Invention

[0005] In order to solve the problem that the existing method of ensuring the stable operation of the boiler water supply structure by setting a reflux valve on the water supply pipeline is prone to water cut-off in the waste heat boiler, the utility model provides a new boiler water supply structure.

[0006] The utility model is realized by adopting the following technical scheme:

[0007] A boiler water supply structure includes an on-line water supply pipeline, a water delivery pipeline, a heat exchanger, a steam drum, a waste heat boiler, and a controller. An on-line water supply pump and an on-line pressure gauge are provided on the on-line water supply pipeline. The on-line water supply pump is equipped with an on-line variable frequency motor. The input end of the controller is connected to the on-line pressure gauge, and the output end of the controller is used to control the rotation frequency of the on-line variable frequency motor.

[0008] Principle description: By combining the on-line variable frequency motor and the on-line pressure gauge, the load of the on-line water supply pump can be adjusted at any time, and it can be adjusted according to the actual production situation at any time, reducing the operating pressure. It can effectively prevent the occurrence of boiler water leakage or waste heat boiler water cut caused by overpressure, thus stabilizing the smooth operation of the boiler water supply structure. When the on-line pressure gauge detects that the pressure value in the on-line water supply pipeline is lower than the set pressure value, the frequency of the on-line variable frequency motor is increased. When the on-line pressure gauge detects that the pressure value in the on-line water supply pipeline is higher than the set pressure value, the frequency of the on-line variable frequency motor is decreased to achieve stable pressure.

[0009] Furthermore, an on-line cut-off valve is also provided on the on-line water supply pipeline. When the liquid level or pressure of the steam drum exceeds the safety value, the on-line cut-off valve is closed.

[0010] Furthermore, the structure also includes a standby water supply pipeline parallel to the on-line water supply pipeline. The on-line water supply pipeline and the standby water supply pipeline together form the water supply pipeline. A standby water supply pump and a standby pressure gauge are provided on the standby water supply pipeline. The standby water supply pump is equipped with a standby variable frequency motor. The input end of the controller is also connected to the standby pressure gauge, and the output end of the controller is also used to control the rotation frequency of the standby variable frequency motor. Setting the standby water supply pipeline can prevent the boiler water supply structure from being deactivated when the on-line water supply pipeline fails, thus causing the production of the coke oven gas methanation reaction to be unable to operate continuously and stably, and further ensuring the stable operation of the boiler water supply structure.

[0011] Furthermore, a standby cut-off valve is provided on the standby water supply pipeline. When the standby water supply pipeline supplies water normally and stably, the standby cut-off valve is closed. When the on-line water supply pump stops abnormally or the on-line pressure gauge detects that the pressure value in the on-line water supply pipeline is lower than the set value, the standby cut-off valve is opened, the standby water supply pump is started, the on-line cut-off valve and the on-line water supply pump are closed, and the on-line water supply pipeline is repaired.

[0012] Furthermore, a flow meter and a flow regulating valve are provided on the water delivery pipeline. The flow regulating valve is adjusted according to the flow rate on the flow meter to further ensure the smooth operation of the boiler water supply structure.

[0013] Furthermore, the flow regulating valve is automatically controlled by the controller according to the flow rate collected by the flow meter to achieve precise regulation.

[0014] Furthermore, the structure further includes a deaerator. The water inlet end of the deaerator is connected to the boiler water. The feed water pipeline is arranged between the deaerator and the heat exchanger. The deaerator is used to remove the dissolved oxygen in the boiler water, thereby obtaining high-quality steam.

[0015] The beneficial effects produced by the present utility model are as follows: The combination of the on-line variable-frequency motor and the on-line pressure gauge realizes the adjustment of the load of the on-line feed water pump at any time, and can be adjusted according to the actual production situation at any time, reducing the operating pressure, effectively preventing the occurrence of boiler water leakage or waste heat boiler water cut-off caused by overpressure, thereby stabilizing the smooth operation of the boiler water supply structure and reducing the uncontrollable risks to the personal safety of on-site operators. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing the embodiments in accordance with the present utility model, and are used together with the specification to explain the principles of the present utility model.

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic diagram of the overall structure of the present utility model.

[0019] In the figure: 1 - deaerator, 2 - on-line feed water pump, 3 - on-line variable-frequency motor, 4 - on-line pressure gauge, 5 - on-line cut-off valve, 6 - heat exchanger, 7 - steam drum, 8 - waste heat boiler, 9 - flow regulating valve, 10 - flow meter, 11 - standby feed water pump, 12 - standby variable-frequency motor, 13 - standby pressure gauge, 14 - standby cut-off valve, 15 - on-line feed water pipeline, 16 - standby feed water pipeline, 17 - water supply pipeline. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] In order to be able to more clearly understand the above-mentioned objects, features and advantages of the present utility model, the following will further describe the solution of the present utility model. It should be noted that, without conflict, the embodiments of the present utility model and the features in the embodiments can be combined with each other.

[0021] In the description, it should be noted that the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance. It should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0022] In the following description, many specific details are set forth in order to provide a thorough understanding of the present utility model, but the present utility model may be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only a part of the embodiments of the present utility model, rather than all of the embodiments.

[0023] The specific embodiments of the present utility model will be described in detail below with reference to the accompanying drawings.

[0024] As Figure 1 shown, a boiler water supply structure includes an on-line water supply pipeline 15, a water delivery pipeline 17, a heat exchanger 6, a steam drum 7, a waste heat boiler 8, and a controller. An on-line water supply pump 2 and an on-line pressure gauge 4 are arranged on the on-line water supply pipeline 15. The on-line water supply pump 2 is equipped with an on-line variable frequency motor 3. The input end of the controller is connected to the on-line pressure gauge 4, and the output end of the controller is used to control the rotation frequency of the on-line variable frequency motor 3.

[0025] Principle description: The combination of the on-line variable frequency motor 3 and the on-line pressure gauge 4 realizes the adjustment of the load of the on-line water supply pump 2 at any time, and can be adjusted according to the actual production situation at any time, reducing the operating pressure, effectively preventing the occurrence of boiler water leakage or water cut-off of the waste heat boiler 8 caused by overpressure, thereby stabilizing the smooth operation of the boiler water supply structure. When the on-line pressure gauge 4 detects that the pressure value in the on-line water supply pipeline 15 is lower than the set pressure value, the frequency of the on-line variable frequency motor 3 is increased. When the on-line pressure gauge 4 detects that the pressure value in the on-line water supply pipeline 15 is higher than the set pressure value, the frequency of the on-line variable frequency motor 3 is decreased to achieve pressure stability. In addition, during actual use, when starting the on-line water supply pump 2, the rotation frequency of the on-line variable frequency motor 3 can be set to the minimum value to save power consumption.

[0026] During specific implementation, an on-line cut-off valve 5 is also arranged on the on-line water supply pipeline 15. When the liquid level or pressure of the steam drum 7 exceeds the safety value, the on-line cut-off valve 5 is closed.

[0027] During specific implementation, the structure further includes a standby water supply pipeline 16 connected in parallel with the on-line water supply pipeline 15. The on-line water supply pipeline 15 and the standby water supply pipeline 16 together form the water supply pipeline. A standby water supply pump 11 and a standby pressure gauge 13 are arranged on the standby water supply pipeline 16. The standby water supply pump 11 is equipped with a standby variable-frequency motor 12. The input end of the controller is also connected to the standby pressure gauge 13, and the output end of the controller is also used to control the rotation frequency of the standby variable-frequency motor 12. The setting of the standby water supply pipeline 16 prevents the boiler water supply structure from being deactivated when the on-line water supply pipeline 15 fails, thus causing the production of the coke oven gas methanation reaction to be unable to operate continuously and stably, and further ensuring the stable operation of the boiler water supply structure.

[0028] During specific implementation, a standby cut-off valve 14 is arranged on the standby water supply pipeline 16. When the standby water supply pipeline 16 supplies water stably and normally, the standby cut-off valve 14 is closed. When the on-line water supply pump 2 stops abnormally or the on-line pressure gauge 4 detects that the pressure value in the on-line water supply pipeline 15 is lower than the set value, the standby cut-off valve 14 is opened, the standby water supply pump 11 is started, the on-line cut-off valve 5 and the on-line water supply pump 2 are closed, and the on-line water supply pipeline 15 is repaired.

[0029] During specific implementation, a flow meter 10 and a flow regulating valve 9 are arranged on the water supply pipeline 17. The flow regulating valve 9 is adjusted according to the flow rate on the flow meter 10, further ensuring the stable operation of the boiler water supply structure.

[0030] In this specific embodiment, the flow regulating valve 9 is automatically controlled by the controller according to the flow rate collected by the flow meter 10 to achieve precise regulation.

[0031] In this specific embodiment, the structure further includes a deaerator 1. The water inlet end of the deaerator 1 is connected to the boiler water. The water supply pipeline is arranged between the deaerator 1 and the heat exchanger 6. The deaerator 1 is used to remove the dissolved oxygen in the boiler water to obtain high-quality steam.

[0032] The above are only specific embodiments of the present invention, enabling those skilled in the art to understand or implement the present invention. Although the above embodiments have been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the foregoing embodiments, and they should all be covered by the protection scope of the claims.

Claims

1. A boiler water supply structure, comprising an online water supply pipeline (15), a water delivery pipeline (17), a heat exchanger (6), a steam drum (7), and a waste heat boiler (8), wherein an online water supply pump (2) is provided on the online water supply pipeline (15), characterized in that: The structure also includes a controller. An online pressure gauge (4) is also provided on the online water supply pipeline (15). The online water supply pump (2) is provided with an online variable frequency motor (3). The input end of the controller is connected to the online pressure gauge (4), and the output end of the controller is used to control the rotation frequency of the online variable frequency motor (3).

2. A boiler water supply structure according to claim 1, characterized in that: An online shut-off valve (5) is also provided on the online water supply pipeline (15).

3. A boiler water supply structure according to claim 1 or 2, characterized in that: The structure further comprises a standby water supply pipeline (16) connected in parallel with the online water supply pipeline (15); the online water supply pipeline (15) and the standby water supply pipeline (16) together constitute a water supply pipeline; the standby water supply pipeline (16) is provided with a standby water supply pump (11) and a standby pressure gauge (13); the standby water supply pump (11) is provided with a standby variable frequency motor (12); the input end of the controller is also connected to the standby pressure gauge (13); and the output end of the controller is also used to control the rotation frequency of the standby variable frequency motor (12).

4. A boiler water supply structure according to claim 3, characterized in that: A spare shut-off valve (14) is provided on the spare water supply pipeline (16).

5. A boiler water supply structure according to claim 1 or 2, characterized in that: A flow meter (10) and a flow regulating valve (9) are provided on the water supply pipeline (17).

6. A boiler water supply structure according to claim 4, characterized in that: A flow meter (10) and a flow regulating valve (9) are provided on the water supply pipeline (17).

7. A boiler water supply structure according to claim 5, characterized in that: The flow regulating valve (9) is automatically controlled by a controller according to the flow collected by the flow meter (10).

8. A boiler water supply structure according to claim 6, characterized in that: The flow regulating valve (9) is automatically controlled by a controller according to the flow collected by the flow meter (10).

9. A boiler water supply structure according to claim 7, characterized in that: The structure further comprises a deaerator (1), the water inlet end of the deaerator (1) is connected to boiler water, and a water supply pipeline is arranged between the deaerator (1) and the heat exchanger (6).

10. A boiler water supply structure according to claim 8, characterized in that: The structure further comprises a deaerator (1), the water inlet end of the deaerator (1) is connected to boiler water, and a water supply pipeline is arranged between the deaerator (1) and the heat exchanger (6).

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