Low-temperature waste heat utilization device

Abstract

The utility model discloses a low-temperature waste heat utilization device which is characterized in that a flue heat exchanger is arranged in a tail flue of a boiler, and water inlets and water outlets of the flue heat exchanger, an isolation heat exchanger, a steam generation assembly, a steam utilization assembly and a condensate water tank are sequentially communicated to form a circulation path; water in the flue heat exchanger is heated through a boiler tail flue and then conveyed into the isolation heat exchanger for heat exchange, hot water heated after heat exchange enters the steam generation assembly to generate steam, the steam enters the steam utilization assembly for steam utilization, and generated condensate water enters the condensate water tank. Condensate water in the condensate water tank and condensate water in the steam generation assembly flow back to the isolation heat exchanger for heating and heat exchange and then flow back to the flue heat exchanger for heating and heat exchange. By means of the technical scheme, effective conversion and utilization of waste heat are achieved, safety and stability of system operation are guaranteed, and the influence on an existing system is small.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat utilization, in particular to a low-temperature waste heat utilization device. Background Art

[0002] In the prior art, for heat energy recovery devices based on steam generators, the flue gas heat absorption circulation system is generally composed of a low-temperature economizer, a water inlet tank, a water outlet tank and a circulation pump. It does not consider how to utilize the existing low-temperature economizer or the hot water of the low-temperature economizer system, and it is impossible to recover the waste heat. In addition, the operating pressure of the existing flue heat exchanger heating condensate system is high, which cannot meet the safety and stability requirements of the condensate system. Utility Model Content

[0003] In view of the above problems, the utility model provides a low-temperature waste heat utilization device, which improves the flue heat exchanger in the prior art, eliminates the water inlet tank and the water storage tank in the prior art, and converts the low-temperature flue gas into steam resources through the flue heat exchanger to serve as a heat source for other processes. In addition, the isolation heat exchanger is used to isolate the steam generation and steam utilization stages from the condensate stage, thereby ensuring the safety and stability of the system operation, and at the same time ensuring that the design pressure of the existing flue heat exchanger for heating the condensate remains unchanged, which has little impact on the existing system.

[0004] To achieve the above-mentioned purpose, the utility model provides a low-temperature waste heat utilization device, comprising: a flue heat exchanger, an isolation heat exchanger, a steam generating component, a steam utilization component and a condensed water tank;

[0005] The flue heat exchanger is arranged in the flue at the tail of the boiler, and the flue heat exchanger, the isolation heat exchanger, the steam generating assembly, the steam utilizing assembly and the water inlet and outlet of the condensed water tank are connected in sequence to form a circulation passage;

[0006] The water in the flue heat exchanger is heated by the tail flue of the boiler and then transported to the isolation heat exchanger for heat exchange. The heated hot water enters the steam generating assembly to generate steam, and the steam enters the steam utilizing assembly for steam utilization. The generated condensed water enters the condensed water tank.

[0007] The condensed water in the condensed water tank and the condensed water in the steam generating assembly flow back to the isolation heat exchanger for heating and heat exchange, and then flow back to the flue heat exchanger for heating and heat exchange.

[0008] In the above technical solution, preferably, the flue heat exchanger is a waste heat utilization component currently arranged in the tail flue of the boiler, the inlet of the flue heat exchanger is connected to the cold water source, and the outlet of the flue heat exchanger outputs the heated hot water to the water unit;

[0009] The pipe at the outlet of the flue heat exchanger is respectively connected to the water inlet and outlet of the isolation heat exchanger to output the hot water heated by the flue heat exchanger to the isolation heat exchanger, and to output the hot water condensed and refluxed to the isolation heat exchanger for heating and heat exchange to the water use unit.

[0010] In the above technical solution, preferably, the low-temperature waste heat utilization device also includes a water replenishment interface, which is connected to the condensed water tank, and the water replenishment interface is used to replenish water to the condensed water tank.

[0011] In the above technical solution, preferably, the low-temperature waste heat utilization device also includes a vacuum pump, which is connected to the condensed water tank, and the vacuum pump is used to discharge the non-condensable gas in the condensed water tank.

[0012] Compared with the prior art, the beneficial effects of the utility model are as follows: by improving the flue heat exchanger in the prior art, the water inlet tank and the water storage tank in the prior art are omitted, and the low-temperature flue gas is converted into steam resources through the flue heat exchanger as a heat source for other processes, thereby realizing the effective conversion and utilization of waste heat. In addition, the isolation effect of the steam generation and steam utilization stage and the condensate stage is realized by the isolation heat exchanger, thereby ensuring the safety and stability of the system operation, and at the same time, the design pressure of the existing flue heat exchanger for heating the condensate water remains unchanged, which has little impact on the existing system. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a structural schematic diagram of a low-temperature waste heat utilization device disclosed in an embodiment of the utility model;

[0014] Figure 2 The present invention is a schematic structural diagram of a low-temperature waste heat utilization device for modifying an existing flue heat exchanger disclosed in an embodiment of the present invention.

[0015] In the figure, the corresponding relationship between each component and the reference numeral is as follows:

[0016] 1. Flue heat exchanger, 2. Isolation heat exchanger, 3. Steam generating assembly, 4. Steam utilizing assembly, 5. Condensate tank, 6. Vacuum pump. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of 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.

[0018] The utility model is further described in detail below in conjunction with the accompanying drawings:

[0019] like Figure 1 As shown, a low-temperature waste heat utilization device provided by the utility model includes: a flue heat exchanger 1, an isolation heat exchanger 2, a steam generating component 3, a steam utilization component 4 and a condensed water tank 5;

[0020] The flue heat exchanger 1 is arranged in the flue at the tail of the boiler, and the water inlet and outlet of the flue heat exchanger 1, the isolation heat exchanger 2, the steam generating assembly 3, the steam utilizing assembly 4 and the condensed water tank 5 are connected in sequence to form a circulation passage;

[0021] The water in the flue heat exchanger 1 is heated by the flue at the tail of the boiler and then transported to the isolation heat exchanger 2 for heat exchange. The heated hot water enters the steam generating assembly 3 to generate steam, and the steam enters the steam utilizing assembly 4 for steam utilization. The generated condensed water enters the condensed water tank 5.

[0022] The condensed water in the condensed water tank 5 and the condensed water in the steam generating assembly 3 flow back to the isolation heat exchanger 2 for heating and heat exchange, and then flow back to the flue heat exchanger 1 for heating and heat exchange.

[0023] In this embodiment, low-temperature flue gas is converted into steam resources through the flue heat exchanger 1 as a heat source for other processes, thereby realizing effective conversion and utilization of waste heat. In addition, the isolation heat exchanger 2 is used to isolate the steam generation and utilization stages from the condensate stage, thereby ensuring the safety and stability of the system operation. At the same time, the design pressure of the existing flue heat exchanger 1 for heating the condensate remains unchanged, which has little impact on the existing system.

[0024] Specifically, the isolation heat exchanger 2 can be in the form of a plate heat exchanger or a shell-and-tube heat exchanger, and a water pump can be added to the pipelines connecting the components for pressurized transportation.

[0025] In addition, the flue heat exchanger 1 in the existing flue gas heat absorption circulation system in the prior art can also be directly modified to save costs and retain part of the structure and function of the original system.

[0026] Therefore, if Figure 2 As shown, preferably, the specific transformation method is that the flue heat exchanger 1 is a waste heat utilization component currently arranged in the flue at the tail of the boiler, the inlet of the flue heat exchanger 1 is connected to the cold water source, and the outlet of the flue heat exchanger 1 outputs the heated hot water to the water unit;

[0027] The pipes at the outlet of the flue heat exchanger 1 are respectively connected to the water inlet and outlet of the isolation heat exchanger 2, so as to output the hot water heated by the flue heat exchanger 1 to the isolation heat exchanger 2, and output the hot water condensed and refluxed to the isolation heat exchanger 2 for heating and heat exchange to the water use unit.

[0028] In this embodiment, the hot water heated by the flue heat exchanger 1 enters the isolation heat exchanger 2 for heat exchange, and the cooled water flows back to the original hot water pipe output by the flue heat exchanger 1, and is further transported to the original water unit. The hot water heated by the isolation heat exchanger 2 enters the steam generation component 3 to generate steam, which is transported to the steam utilization component 4 through the steam pipe. After the steam is fully utilized, it becomes condensed water and enters the condensed water tank 5. The condensed water in the condensed water tank 5 flows back to the steam generation component 3, and the condensed water in the steam generation component 3 flows back to the isolation heat exchanger 2 for heating and heat exchange.

[0029] Among them, the design pressure of the flue heat exchanger 1 heating condensate system is generally 3-5Mpa. The isolation heat exchanger 2 of the utility model can ensure that the operating pressure of the original flue heat exchanger 1 heating condensate system remains unchanged, and has little impact on the original system. As part of the boiler feed water, it is crucial to ensure the safety and stability of the operation of condensate for the entire unit. The isolation heat exchanger 2 of the utility model plays an isolation role, and the steam generation and steam utilization ends are not directly in contact with the condensate system, which ensures the safety and stability of the operation of the condensate system.

[0030] In the above embodiment, preferably, the low-temperature waste heat utilization device further includes a water replenishment interface, which is connected to the condensed water tank 5 and is used to replenish water to the condensed water tank 5. Preferably, the low-temperature waste heat utilization device further includes a vacuum pump 6, which is connected to the condensed water tank 5 and is used to discharge the non-condensable gas in the condensed water tank 5. The provision of the water replenishment interface and the vacuum pump 6 enables the operation of the entire low-temperature waste heat utilization device to proceed smoothly.

[0031] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A low-temperature waste heat utilization device, characterized in that: include: Flue heat exchangers, isolation heat exchangers, steam generation components, steam utilization components and condensate tanks; The flue heat exchanger is arranged in the flue at the tail of the boiler, and the flue heat exchanger, the isolation heat exchanger, the steam generating assembly, the steam utilizing assembly and the water inlet and outlet of the condensed water tank are connected in sequence to form a circulation passage; The water in the flue heat exchanger is heated by the tail flue of the boiler and then transported to the isolation heat exchanger for heat exchange. The heated hot water enters the steam generating assembly to generate steam, and the steam enters the steam utilizing assembly for steam utilization. The generated condensed water enters the condensed water tank. The condensed water in the condensed water tank and the condensed water in the steam generating assembly flow back to the isolation heat exchanger for heating and heat exchange, and then flow back to the flue heat exchanger for heating and heat exchange.

2. The low-temperature waste heat utilization device according to claim 1, characterized in that: The flue heat exchanger is a waste heat utilization component currently arranged in the flue at the tail of the boiler, the inlet of the flue heat exchanger is connected to the cold water source, and the outlet of the flue heat exchanger outputs the heated hot water to the water unit; The pipe at the outlet of the flue heat exchanger is respectively connected to the water inlet and outlet of the isolation heat exchanger to output the hot water heated by the flue heat exchanger to the isolation heat exchanger, and to output the hot water condensed and refluxed to the isolation heat exchanger for heating and heat exchange to the water use unit.

3. The low temperature waste heat utilization device according to claim 1 or 2, characterized in that: It also includes a water replenishment interface, which is connected to the condensed water tank and is used to replenish water to the condensed water tank.

4. The low temperature waste heat utilization device according to claim 3, characterized in that: It also includes a vacuum pump, which is connected to the condensed water tank and is used to discharge the non-condensable gas in the condensed water tank.

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