阅读说明：本技术 一种利用空压机余热辅助锅炉进水预热的系统 (System for utilize air compressor machine waste heat to assist boiler and advance heat of intaking ) 是由 何海军 赵静 曾鑫 李振 马洪洲 于 2021-01-06 设计创作，主要内容包括：本发明属于空压机余热回收利用技术领域,公开了一种利用空压机余热辅助锅炉进水预热的系统,包括锅炉进水水箱、换热器以及空压机余热回收机组,锅炉进水水箱设置有锅炉进水水箱补水管道及锅炉进水水箱出水管道,换热器设置在锅炉进水水箱内,空压机余热回收机组包括空压机润滑油回路及循环水回路,空压机润滑油回路的进口与空压机的润滑油出口连通,空压机润滑油回路的出口与空压机的润滑油进口连通,循环水回路的进水口通过循环水回水管道与换热器的出水口连通,循环水回路的出水口通过循环水供水管道与换热器的进水口连通,空压机润滑油回路与循环水回路进行热量交换,换热器与锅炉进水水箱内的锅炉回水热量交换,使空压机余热得到充分利用。(The invention belongs to the technical field of air compressor waste heat recovery and utilization, and discloses a system for assisting boiler feed water preheating by utilizing air compressor waste heat, which comprises a boiler feed water tank, a heat exchanger and an air compressor waste heat recovery unit, wherein the boiler feed water tank is provided with a boiler feed water tank water supply pipeline and a boiler feed water tank water outlet pipeline, the heat exchanger is arranged in the boiler feed water tank, the air compressor waste heat recovery unit comprises an air compressor lubricating oil loop and a circulating water loop, an inlet of the air compressor lubricating oil loop is communicated with a lubricating oil outlet of an air compressor, an outlet of the air compressor lubricating oil loop is communicated with a lubricating oil inlet of the air compressor, a water inlet of the circulating water loop is communicated with a water outlet of the heat exchanger through a circulating water return pipeline, a water outlet of the circulating water loop is communicated with, the heat exchanger exchanges heat with boiler return water in the boiler water inlet water tank, so that the waste heat of the air compressor is fully utilized.)

1. The utility model provides an utilize air compressor machine waste heat to assist boiler system of preheating of intaking which characterized in that includes:

the boiler water inlet tank (14), the boiler water inlet tank (14) is provided with a boiler water inlet tank water replenishing pipeline (8) and a boiler water inlet tank water outlet pipeline (19), the boiler water inlet tank water replenishing pipeline (8) is used for guiding boiler return water into the boiler water inlet tank (14), and the boiler water inlet tank water outlet pipeline (19) is used for guiding the boiler return water in the boiler water inlet tank (14) into the boiler;

a heat exchanger (22), the heat exchanger (22) being disposed within the boiler feed water tank (14), the heat exchanger (22) being configured to exchange heat with boiler return water within the boiler feed water tank (14);

air compressor machine waste heat recovery unit (28), air compressor machine waste heat recovery unit (28) are including air compressor machine lubricating oil return circuit and circulating water return circuit, the import in air compressor machine lubricating oil return circuit and the lubricating oil export intercommunication of air compressor machine (27), the export in air compressor machine lubricating oil return circuit with the lubricating oil import intercommunication of air compressor machine (27), the water inlet in circulating water return circuit pass through circulating water return water pipeline (34) with the delivery port intercommunication of heat exchanger (22), the delivery port in circulating water return circuit pass through circulating water supply pipe (35) with the water inlet intercommunication of heat exchanger (22), air compressor machine lubricating oil return circuit with the circulating water return circuit carries out heat exchange.

2. The system for assisting in preheating boiler inlet water by utilizing waste heat of air compressor according to claim 1, further comprising a boiler return water tank (1), wherein the boiler return water tank (1) is provided with a boiler return water tank water supply pipeline (3) and a boiler return water tank water outlet pipeline (17), the boiler return water tank water supply pipeline (3) is used for guiding boiler return water into the boiler return water tank (1), and the boiler return water tank water outlet pipeline (17) and the boiler inlet water tank water outlet pipeline (19) supply water to the boiler together.

3. The system for preheating inlet water of an air compressor waste heat auxiliary boiler according to claim 2, comprising a temperature control proportional control valve (24), wherein the temperature control proportional control valve (24) is provided with a first control valve inlet, a second control valve inlet and a control valve outlet, a boiler return water tank outlet pipe (17) is communicated with the first control valve inlet of the temperature control proportional control valve (24), a boiler inlet water tank outlet pipe (19) is communicated with the second control valve inlet of the temperature control proportional control valve (24), and the control valve outlet is communicated with a boiler inlet water supply pipe (26).

4. The system for assisting preheating of boiler inlet water by utilizing waste heat of air compressor as claimed in claim 3, wherein the boiler inlet water supply pipeline (26) is provided with a water supply pump (25).

5. The system for assisting in preheating boiler inlet water by utilizing waste heat of air compressor as claimed in claim 2, wherein the boiler return water tank water supply pipeline (3) and the boiler inlet water tank water supply pipeline (8) are both communicated with a boiler return water pipeline (6).

6. The system for assisting in preheating boiler inlet water by utilizing waste heat of air compressor as claimed in claim 5, wherein the boiler return water pipe (6) is provided with a boiler return water filter (12), and the boiler return water filter (12) is located at a boiler return water inlet (13) of the boiler return water pipe (6).

7. The system for assisting boiler water inlet preheating by utilizing waste heat of air compressor according to claim 2, characterized in that the boiler water return tank water supplementing pipeline (3) is provided with a boiler water return tank water supplementing electromagnetic valve (4), a boiler water return tank cable floating ball (2) is arranged in the boiler water return tank (1), an electric line of the boiler water return tank cable floating ball (2) is connected with the boiler water return tank water supplementing electromagnetic valve (4), and the boiler water return tank cable floating ball (2) is configured to control on-off of the boiler water return tank water supplementing electromagnetic valve (4).

8. The system for assisting boiler feed water preheating by utilizing waste heat of air compressors according to any one of claims 1 to 7, wherein a boiler feed water tank water replenishing solenoid valve (9) is arranged on the boiler feed water tank water replenishing pipeline (8), a boiler feed water tank cable floating ball (7) is arranged in the boiler feed water tank (14), an electric line of the boiler feed water tank cable floating ball (7) is connected with the boiler feed water tank water replenishing solenoid valve (9), and the boiler feed water tank cable floating ball (7) is configured to control the on-off of the boiler feed water tank water replenishing solenoid valve (9).

9. The system for assisting boiler inlet water preheating by utilizing waste heat of an air compressor as claimed in claim 1, wherein the circulating water return pipe (34) is provided with a circulating water pump (23), a thermocouple (15) is arranged in the boiler inlet water tank (14), an electric line of the thermocouple (15) is connected with the circulating water pump (23), and the thermocouple (15) is configured to control the on-off of the circulating water pump (23).

10. The system for preheating by utilizing air compressor waste heat to assist the boiler feed water according to claim 9, wherein the circulating water return pipe (34) is provided with a circulating water filter (33).

Technical Field

The invention relates to the technical field of air compressor waste heat recycling, in particular to a system for assisting boiler feed water preheating by utilizing air compressor waste heat.

Background

The air compressor is a necessary power device for producing and conveying compressed air by a boiler, and generally has a special air compressor room for conveying the compressed air to compressed air devices for boilers, dust collectors and the like through pipelines. At present, the most used screw air compressors are used, only about 20% of electric energy consumed by the screw air compressors in the operation process is converted into air potential energy, and the rest about 80% of electric energy is converted into heat energy and finally discharged into the air in a water cooling or air cooling mode, so that a great deal of waste of the heat energy is caused. The heating circulating water quantity of the coal-fired hot water boiler is large in winter, the outlet water temperature of the boiler is generally controlled to be 60-80 ℃, and the return water temperature of the boiler is generally controlled to be about 40 ℃. Therefore, how to recycle the waste heat of the air compressor and preheat the boiler return water for the boiler becomes a technical problem to be solved urgently by technical personnel in the field.

Disclosure of Invention

The invention aims to provide a system for assisting boiler feed water preheating by utilizing waste heat of an air compressor so as to solve the problem of resource waste caused by heat energy loss of the air compressor.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides a system for utilize air compressor machine waste heat to assist boiler to advance water and preheat, includes:

the boiler water inlet tank is provided with a boiler water inlet tank water supplementing pipeline and a boiler water inlet tank water outlet pipeline, the boiler water inlet tank water supplementing pipeline is used for guiding boiler return water into the boiler water inlet tank, and the boiler water inlet tank water outlet pipeline is used for guiding the boiler return water in the boiler water inlet tank into the boiler;

the heat exchanger is arranged in the boiler water inlet tank and is configured to exchange heat with boiler return water in the boiler water inlet tank;

the air compressor waste heat recovery unit comprises an air compressor lubricating oil loop and a circulating water loop, wherein an inlet of the air compressor lubricating oil loop is communicated with a lubricating oil outlet of the air compressor, an outlet of the air compressor lubricating oil loop is communicated with a lubricating oil inlet of the air compressor, a water inlet of the circulating water loop is communicated with a water outlet of the heat exchanger through a circulating water return pipeline, a water outlet of the circulating water loop is communicated with a water inlet of the heat exchanger through a circulating water supply pipeline, and the air compressor lubricating oil loop is subjected to heat exchange with the circulating water loop.

Preferably, the system further comprises a boiler return water tank, wherein the boiler return water tank is provided with a boiler return water tank water replenishing pipeline and a boiler return water tank water outlet pipeline, the boiler return water tank water replenishing pipeline is used for guiding boiler return water into the boiler return water tank, and the boiler return water tank water outlet pipeline and the boiler inlet water tank water outlet pipeline supply water to the boiler together.

Preferably, the system comprises a temperature control proportional control valve, wherein the temperature control proportional control valve is provided with a first control valve inlet, a second control valve inlet and a control valve outlet, a boiler return water tank outlet pipeline is communicated with the first control valve inlet of the temperature control proportional control valve, a boiler inlet water tank outlet pipeline is communicated with the second control valve inlet of the temperature control proportional control valve, and the control valve outlet is communicated with a boiler inlet water supply pipeline.

Preferably, the boiler water inlet and supply pipeline is provided with a water supply pump.

Preferably, the boiler return water tank water replenishing pipeline and the boiler water inlet tank water replenishing pipeline are both communicated with a boiler return water pipeline.

Preferably, the boiler return water pipeline is provided with a boiler return water filter, and the boiler return water filter is positioned at a boiler return water inlet of the boiler return water pipeline.

Preferably, the boiler return water tank water replenishing pipeline is provided with a boiler return water tank water replenishing electromagnetic valve, a boiler return water tank cable floating ball is arranged in the boiler return water tank, an electric line of the boiler return water tank cable floating ball is connected with the boiler return water tank water replenishing electromagnetic valve, and the boiler return water tank cable floating ball is configured to control the on-off of the boiler return water tank water replenishing electromagnetic valve.

Preferably, the boiler water inlet tank water replenishing pipeline is provided with a boiler water inlet tank water replenishing electromagnetic valve, a boiler water inlet tank cable floating ball is arranged in the boiler water inlet tank, an electric circuit of the boiler water inlet tank cable floating ball is connected with the boiler water inlet tank water replenishing electromagnetic valve, and the boiler water inlet tank cable floating ball is configured to control the on-off of the boiler water inlet tank water replenishing electromagnetic valve.

Preferably, the circulating water return pipeline is provided with a circulating water pump, a thermocouple is arranged in the boiler water inlet tank, an electric line of the thermocouple is connected with the circulating water pump, and the thermocouple is configured to control the starting and stopping of the circulating water pump.

Preferably, the circulating water return pipeline is provided with a circulating water filter.

The invention has the beneficial effects that: according to the system for assisting the boiler to preheat the inlet water by utilizing the waste heat of the air compressor, the heat exchanger is arranged in the boiler inlet water tank, the air compressor is communicated with the air compressor waste heat recovery unit, the air compressor waste heat recovery unit can exchange the heat of high-temperature lubricating oil in the air compressor to circulating water, the circulating water flows through the heat exchanger communicated with the air compressor waste heat recovery unit, the boiler return water exchanges heat with the circulating water in the heat exchanger in the boiler inlet water tank, the boiler return water in the boiler inlet water tank rises to reach the boiler inlet water temperature, and then enters the boiler through the boiler inlet water tank outlet pipeline for use, so that the heat energy of the air compressor is fully utilized, the waste of the heat energy of the air compressor is avoided, the boiler inlet water temperature can meet the use requirement, the energy consumption of the boiler is reduced, and.

Drawings

FIG. 1 is a schematic diagram of a system for assisting boiler feed water preheating by using waste heat of an air compressor provided by the invention.

In the figure:

1. a boiler return water tank; 2. a cable floating ball of a boiler return water tank; 3. a boiler return water tank water replenishing pipeline; 4. a water replenishing electromagnetic valve of a boiler backwater water tank; 5. a water replenishing butterfly valve of a boiler return water tank; 6. a boiler return water pipe; 7. a cable floating ball of a boiler water inlet tank; 8. a boiler water inlet tank water replenishing pipeline; 9. a water replenishing electromagnetic valve of a boiler water inlet tank; 10. a water-replenishing butterfly valve of a boiler water inlet tank; 11. a boiler backwater butterfly valve; 12. a boiler backwater filter; 13. a boiler return water inlet; 14. a boiler water inlet tank; 15. a thermocouple; 16. a circulating water return butterfly valve; 17. a water outlet pipeline of a boiler backwater water tank; 18. a water outlet butterfly valve of a boiler return water tank; 19. a water outlet pipeline of a boiler water inlet tank; 20. a water outlet butterfly valve of a boiler water inlet tank; 21. a circulating water supply butterfly valve; 22. a heat exchanger; 23. a water circulating pump; 24. a temperature control proportional regulating valve; 25. a water supply pump; 26. a boiler water inlet pipe; 27. an air compressor; 28. an air compressor waste heat recovery unit; 29. a rubber soft joint is arranged on the side of the air compressor; 30. a side water supply butterfly valve of the air compressor; 31. the side of the air compressor returns water to the rubber soft joint; 32. a side water return butterfly valve of the air compressor; 33. a circulating water filter; 34. a circulating water return pipeline; 35. a circulating water supply pipeline.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "left", "right", and the like are used based on the orientations and positional relationships shown in the drawings only for convenience of description and simplification of operation, and do not indicate or imply that the referred device or element must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

The embodiment provides a system for assisting boiler inlet water preheating by utilizing air compressor waste heat, which comprises a boiler inlet water tank 14, a heat exchanger 22 and an air compressor waste heat recovery unit 28, wherein the boiler inlet water tank 14 is provided with a boiler inlet water tank water supplementing pipeline 8 and a boiler inlet water tank water outlet pipeline 19, boiler return water enters the boiler inlet water tank 14 through the boiler inlet water tank water supplementing pipeline 8, and boiler return water heated in the boiler inlet water tank 14 enters a boiler for use through the boiler inlet water tank water outlet pipeline 19; the heat exchanger 22 is arranged in the boiler water inlet tank 14, and the heat exchanger 22 exchanges heat with boiler return water in the boiler water inlet tank 14, so that the boiler return water in the boiler water inlet tank 14 is heated; the air compressor waste heat recovery unit 28 comprises an air compressor lubricating oil loop and a circulating water loop, wherein an inlet of the air compressor lubricating oil loop is communicated with a lubricating oil outlet of the air compressor 27, an outlet of the air compressor lubricating oil loop is communicated with a lubricating oil inlet of the air compressor 27, high-temperature lubricating oil in the air compressor 27 returns to the air compressor 27 after passing through the air compressor lubricating oil loop, a water inlet of the circulating water loop is communicated with a water outlet of the heat exchanger 22 through a circulating water return pipeline 34, a water outlet of the circulating water loop is communicated with a water inlet of the heat exchanger 22 through a circulating water supply pipeline 35, circulating water circularly flows between the heat exchanger 22 and the circulating water loop, heat exchange is carried out between the air compressor lubricating oil loop and the circulating water loop, the high-temperature lubricating oil in the air compressor 27 exchanges heat with circulating water in the circulating water loop through the air compressor The temperature of the boiler return water in the boiler inlet water tank 14 rises, and then the boiler return water with the increased temperature flows into the boiler through the boiler inlet water tank outlet pipe 19 for use.

Optionally, the circulating water return pipeline 34 is provided with a circulating water return butterfly valve 16 and an air compressor side water return butterfly valve 32, the circulating water return butterfly valve 16 is arranged at one end of the circulating water return pipeline 34 close to the heat exchanger 22, and the air compressor side water return butterfly valve 32 is arranged at one end of the circulating water return pipeline 34 close to the air compressor waste heat recovery unit 28; the circulating water supply pipe 35 is provided with circulating water supply butterfly valve 21 and air compressor side water supply butterfly valve 30, circulating water supply butterfly valve 21 sets up the one end that is close to heat exchanger 22 at circulating water supply pipe 35, air compressor side water supply butterfly valve 30 sets up the one end that is close to air compressor machine waste heat recovery unit 28 at circulating water supply pipe 35, set up circulating water return butterfly valve 16, air compressor machine side return water butterfly valve 32, circulating water supply butterfly valve 21 and air compressor machine side water supply butterfly valve 30, the convenience is maintained circulating water return pipe 34, circulating water supply pipe 35, heat exchanger 22 and air compressor machine waste heat recovery unit 28.

Furthermore, a water inlet of the circulating water loop is provided with an air compressor side backwater rubber soft joint 31, the water inlet of the circulating water loop is connected with a circulating water backwater pipeline 34 through the air compressor side backwater rubber soft joint 31, the water inlet of the circulating water loop is conveniently connected with the circulating water backwater pipeline 34 through the air compressor side backwater rubber soft joint 31, and the sealing performance of the connection position is good; the water outlet of the circulating water loop is provided with the air compressor side water supply rubber soft joint 29, the water outlet of the circulating water loop is connected with the circulating water supply pipeline 35 through the air compressor side water supply rubber soft joint 29, the water outlet of the circulating water loop is conveniently connected with the circulating water supply pipeline 35 through the air compressor side water supply rubber soft joint 29, and the sealing performance of the joint is good.

Preferably, the heat exchanger 22 is a closed self-cleaning heat exchanger, the closed self-cleaning heat exchanger includes a water inlet pipe, a coil pipe, a water return pipe and a support, the water inlet pipe is communicated with one end of the coil pipe, the water return pipe is communicated with the other end of the coil pipe, the coil pipe is placed on the support, the support supports the coil pipe, a water inlet of the water inlet pipe is a water inlet of the heat exchanger 22, and a water inlet of the water inlet pipe is communicated with the circulating water supply pipe 35; the water outlet of the water return pipeline is the water outlet of the heat exchanger 22, and the water outlet of the water return pipeline is communicated with a circulating water return pipeline 34; the coil pipe material is nonrust steel pipe, and the appearance is the heliciform, and the coil pipe internal circulation is demineralized water, and the outer medium of coil pipe is the boiler return water, and the coil pipe can vibrate because of the change of the inside and outside medium temperature of coil pipe, because incrustation scale and stainless steel expansion coefficient are different, and the incrustation scale that the coil pipe surface formed can drop by oneself when vibrating, effectively avoids the incrustation scale accumulation.

The system for assisting the boiler to feed water and preheat by utilizing waste heat of the air compressor further comprises a boiler water return tank 1, the boiler water return tank 1 is provided with a boiler water return tank water supplementing pipeline 3 and a boiler water return tank water outlet pipeline 17, boiler return water flows into the boiler water return tank 1 through the boiler water return tank water supplementing pipeline 3, boiler return water in the boiler water return tank 1 is supplied to the boiler together with a boiler water inlet tank water outlet pipeline 19 through the boiler water return tank water outlet pipeline 17, on one hand, sufficient supply of boiler inlet water is guaranteed, on the other hand, boiler return water in the boiler water return tank 1 is mixed with boiler return water which flows out through the boiler water inlet tank water outlet pipeline 17 and is heated in the boiler water inlet tank 14 through the boiler water inlet tank water outlet pipeline 19, the water temperature entering the boiler can be effectively prevented from being too high, and uneven.

Optionally, the boiler return water tank outlet pipe 17 is provided with a boiler return water tank outlet butterfly valve 18, so that the boiler return water tank outlet pipe 17 is convenient to maintain; the boiler water inlet tank outlet pipe 19 is provided with a boiler water inlet tank outlet butterfly valve 20, so that the boiler water inlet tank outlet pipe 19 is convenient to maintain.

Optionally, the embodiment further comprises a temperature control proportional regulating valve 24, the temperature control proportional regulating valve 24 is provided with a first regulating valve inlet, a second regulating valve inlet and a regulating valve outlet, the boiler return water tank outlet pipe 17 is communicated with the first regulating valve inlet, the water of the boiler return water tank outlet pipe 17 passes through the first regulating valve inlet, the boiler inlet water tank outlet pipe 19 is communicated with the second regulating valve inlet, the water of the boiler inlet water tank outlet pipe 19 passes through the second regulating valve inlet, the water of the first regulating valve inlet is mixed with the water of the second regulating valve inlet at the regulating valve outlet, the regulating valve outlet is communicated with a boiler inlet water supply pipe 26, the water outlet flow of the boiler return water tank outlet pipeline 17 and the water outlet flow of the boiler inlet water tank outlet pipeline 19 are controlled by the temperature control proportional control valve 24, so that the water entering the boiler from the boiler inlet water supply pipeline 26 is ensured to be stabilized in a proper temperature range.

As the preferred technical scheme, the boiler water inlet and supply pipeline 26 is provided with the water supply water pump 25, and the water of the boiler water inlet and supply pipeline 26 is provided with power through the water supply water pump 25, so that the flow speed and the flow of the water entering the boiler are increased, and the water inlet efficiency is further increased.

Optionally, the boiler return water tank water replenishing pipeline 3 and the boiler inlet water tank water replenishing pipeline 8 are communicated with the boiler return water pipeline 6, boiler return water firstly flows into the boiler return water pipeline 6, then one part of the boiler return water in the boiler return water pipeline 6 enters the boiler return water tank 1 through the boiler return water tank water replenishing pipeline 3, and the other part of the boiler return water enters the boiler inlet water tank 14 through the boiler inlet water tank water replenishing pipeline 8, so that the requirements of the boiler return water tank 1 and the boiler inlet water tank 14 on the boiler return water are met; the boiler return water pipe 6 is provided with a boiler return water butterfly valve 11, and the boiler return water butterfly valve 11 is located at a boiler return water inlet 13 of the boiler return water pipe 6 to control the flow of boiler return water passing through the boiler return water pipe 6.

As preferred technical scheme, boiler return water pipe 6 is provided with boiler return water filter 12, and boiler return water filter 12 is located boiler return water entry 13 department of boiler return water pipe 6, through setting up boiler return water filter 12, can effectively prevent that impurities such as fine sand, gravel in the boiler return water from causing the jam, guarantees that the system that utilizes air compressor machine waste heat auxiliary boiler to intake to preheat that this embodiment provided can steady operation.

Optionally, the boiler return water tank water replenishing pipeline 3 is provided with a boiler return water tank water replenishing electromagnetic valve 4, a boiler return water tank cable floating ball 2 is arranged in the boiler return water tank 1, an electric line of the boiler return water tank cable floating ball 2 is connected with the boiler return water tank water replenishing electromagnetic valve 4, and the boiler return water tank cable floating ball 2 is used for controlling the on-off of the boiler return water tank water replenishing electromagnetic valve 4 so as to realize the automatic water replenishing of the boiler return water tank 1. When the water level of the boiler return water tank 1 reaches a preset high-level control height, a cable floating ball 2 of the boiler return water tank rises, a water replenishing electromagnetic valve 4 of the boiler return water tank is automatically closed, and the boiler return water tank 1 stops replenishing water; as boiler return water is consumed in the boiler return water tank 1, the boiler return water tank cable floating ball 2 continuously descends along with the descending of the water level of the boiler return water tank 1, when the water level descends to a preset low-level control height, the boiler return water tank water replenishing electromagnetic valve 4 is automatically opened, the boiler return water tank 1 starts replenishing water, and the automation level of the boiler return water tank 1 water replenishing is increased. Preferably, the boiler return water tank water replenishing pipeline 3 is provided with a boiler return water tank water replenishing butterfly valve 5, and the boiler return water tank water replenishing butterfly valve 5 is used for controlling the on-off of the boiler return water tank water replenishing pipeline 3 when the boiler return water tank water replenishing electromagnetic valve 4 breaks down.

Further, boiler intake water tank moisturizing pipeline 8 is provided with boiler intake water tank moisturizing solenoid valve 9, is provided with boiler intake water tank cable floater 7 in the boiler intake water tank 14, and the electric line of boiler intake water tank cable floater 7 is connected with boiler intake water tank moisturizing solenoid valve 9, and boiler intake water tank cable floater 7 is used for controlling the break-make of boiler intake water tank moisturizing solenoid valve 9 to realize the automatic water supply of boiler intake water tank 14. When the water level of the boiler water inlet tank 14 reaches a preset high-level control height, a cable floating ball 7 of the boiler water inlet tank rises, a water replenishing electromagnetic valve 9 of the boiler water inlet tank is automatically closed, and the boiler water inlet tank 14 stops replenishing water; as the boiler backwater in the boiler inlet water tank 14 is consumed, the boiler inlet water tank cable floating ball 7 continuously descends along with the descending of the water level of the boiler inlet water tank 14, when the water level descends to a preset low-level control height, the boiler inlet water tank water replenishing electromagnetic valve 9 is automatically opened, and the boiler inlet water tank 14 starts replenishing water. Preferably, the boiler inlet water tank water replenishing pipeline 8 is provided with a boiler inlet water tank water replenishing butterfly valve 10, and the boiler inlet water tank water replenishing butterfly valve 10 is used for controlling the on-off of the boiler inlet water tank water replenishing pipeline 8 when the boiler inlet water tank water replenishing electromagnetic valve 9 breaks down.

The circulating water return pipe 34 of this embodiment is provided with circulating water pump 23, is provided with thermocouple 15 in the boiler water inlet tank 14, and thermocouple 15's electric wire is connected with circulating water pump 23, and thermocouple 15 is used for controlling opening of circulating water pump 23 and stops to realize the automatic opening of circulating water pump 23 and stop. When the thermocouple 15 detects that the temperature of the boiler backwater in the boiler inlet water tank 14 reaches 65 ℃, the thermocouple 15 controls the circulating water pump 23 to automatically stop; when the thermocouple 15 detects that the temperature of water in the hot water tank is reduced to 60 ℃, the thermocouple 15 controls the circulating water pump 23 to be automatically started, and further automatic control over the temperature of boiler return water in the boiler inlet water tank 14 is achieved.

Optionally, the circulating water return pipe 34 is provided with the circulating water filter 33, and by providing the circulating water filter 33, the circulating water in the circulating water return pipe 34 or the circulating water supply pipe 35 can be effectively prevented from being blocked due to impurities such as fine sand and small stones.

The working process of the system for assisting the boiler to preheat the inlet water by utilizing the waste heat of the air compressor provided by the embodiment is as follows:

after boiler return water passes through a boiler of a boiler return water filter 12 in a boiler return water pipeline 6, one part of the boiler return water enters a boiler inlet water tank 14 through a boiler inlet water tank water supplementing pipeline 8, the other part of the boiler return water enters a boiler return water tank 1 through a boiler return water tank water supplementing pipeline 3, a hollow press lubricating oil loop and a circulating water loop of an air compressor waste heat recovery unit 28 exchange heat, the heat of high-temperature lubricating oil in an air compressor 27 is exchanged for circulating water in the circulating water loop by the air compressor lubricating oil loop, then the circulating water flows through a heat exchanger 22 to be transferred to boiler return water in the boiler inlet water tank 14, the temperature of the boiler return water in the boiler inlet water tank 14 rises, then the boiler return water in the boiler inlet water tank 14 flows to a temperature control proportional control regulating valve 24 through a boiler inlet water tank water outlet pipeline 19, and meanwhile, the boiler return water in the boiler return water tank 1 flows to the temperature control proportional regulating valve 24 through The boiler return water is mixed, and the mixed water flows out through the boiler water inlet and supply pipeline 26 to be used by the boiler.

Compared with the prior boiler backwater technology, the invention has the following advantages:

the energy-saving and environment-friendly air compressor fully utilizes the redundant heat generated in the working process of the air compressor 27, only consumes a small amount of electric energy, does not need to consume primary energy such as natural gas, coal and the like, does not directly discharge pollutants, and has obvious energy-saving and environment-friendly advantages; the automatic level is high, the system operation can realize high automatic control, the boiler return water tank 1 and the boiler inlet water tank 14 can automatically supply water, and the circulating water pump 23 can also be automatically started and stopped; the economic benefit is remarkable, the operation cost of the invention comprises a small amount of electricity charge, labor charge and operation and maintenance charge, the annual operation cost is 20 percent of that of a coal-fired boiler and 15 percent of that of a gas-fired boiler; the method is safe and reliable, the waste heat resources of the air compressor 27 are stable and reliable, the waste heat resources of the air compressor 27 are preferentially utilized, and the consumption of primary energy is reduced.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Numerous obvious variations, adaptations and substitutions will occur to those skilled in the art without departing from the scope of the invention. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.