Waste heat recovery system and method and steam pocket water supplementing system

Abstract

According to the waste heat recovery system and method and the steam pocket water supplementing system, on one hand, deoxygenated water output by a deaerator is fed into a heat exchange mechanism through a first pipeline so as to absorb waste heat in a flue of a heating furnace; the flow of the deoxygenated water entering the heat exchange mechanism is controlled through the first flow adjusting mechanism, full utilization of flue waste heat is guaranteed, and the situation that the deoxygenated water is vaporized due to too little deoxygenated water, and consequently water supplementing of a steam pocket is insufficient is avoided. On the other hand, one part of the deoxygenated water after heat exchange is supplemented to the steam pocket through the second pipeline, the other part of the deoxygenated water is sent back to the deaerator through the third pipeline, and when the amount of water needing to be supplemented by the steam pocket is small, the flow of the third pipeline is controlled to be increased through the third flow control mechanism, so that it is guaranteed that the amount of the deoxygenated water passing through the heat exchange mechanism is kept above the set threshold value; therefore, difficult water replenishing of the steam pocket caused by too little vaporization of the deoxygenated water passing through the heat exchange mechanism is avoided, meanwhile, the heat exchange amount of the heat exchange mechanism is guaranteed, flue waste heat can be rapidly released, and meanwhile safe operation of a waste heat recovery system is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of waste heat recovery and drum water replenishment of heating furnaces, and in particular to a waste heat recovery system, method and drum water replenishment system. Background Art

[0002] In the metallurgical industry, the performance of the heated slab directly affects the slab rolling process and the quality of the finished product. The heating furnace used to heat the slab is the first process in the hot rolling production line.

[0003] In order to meet the needs of high-efficiency and low-energy consumption development, it is necessary to set up a waste heat utilization system to recycle the waste heat of the heating furnace flue. The existing waste heat utilization system mainly includes a heat exchanger arranged in the flue of the heating furnace, which uses the flue waste heat to heat the drum make-up water of the vaporization system. The amount of water in the heat exchanger is affected by the demand for drum make-up water. When the demand for make-up water is low, the amount of water in the heat exchanger is correspondingly small, and it is easy to vaporize under the action of the flue waste heat, resulting in difficulty in drum make-up water, seriously affecting the stable operation of the original vaporization system, and is not conducive to the safe operation of the waste heat utilization system. Summary of the invention

[0004] In view of the above problems, the present application is proposed to provide a waste heat recovery system, method and drum water replenishment system that overcome the above problems or at least partially solve the above problems.

[0005] In a first aspect, a waste heat recovery system is provided, comprising:

[0006] A heat exchange mechanism is arranged in the flue of the heating furnace;

[0007] A first pipeline, the inlet of which is connected to the outlet of the deaerator, and the outlet of which is connected to the inlet of the heat exchange mechanism;

[0008] A second pipeline, the inlet of which is connected to the outlet of the heat exchange mechanism, and the outlet of which is connected to the inlet of the steam drum;

[0009] A third pipeline, the inlet of which is connected to the outlet of the heat exchange mechanism, and the outlet of which is connected to the inlet of the deaerator;

[0010] A first flow regulating mechanism, disposed in the first pipeline, for controlling the deoxygenated water in the first pipeline to enter the heat exchange mechanism at a flow rate greater than a set threshold;

[0011] A second flow regulating mechanism is provided in the second pipeline and is used to regulate the flow of deoxygenated water fed into the steam drum through the second pipeline;

[0012] The third flow regulating mechanism is arranged in the third pipeline and is used to regulate the flow of deoxygenated water sent into the deaerator through the third pipeline so that the flow of deoxygenated water sent out by the heat exchange mechanism matches the flow of deoxygenated water sent into the heat exchange mechanism.

[0013] Optionally, the waste heat recovery system also includes:

[0014] Liquid level gauge, installed on the drum;

[0015] The first controller is electrically connected to the liquid level meter and the second flow regulating mechanism, respectively, and is used to receive the actual liquid level of the steam drum sent by the liquid level meter, and control the second flow regulating mechanism to adjust the flow of deoxygenated water sent into the steam drum through the second pipeline according to the actual liquid level.

[0016] Optionally, the waste heat recovery system also includes:

[0017] A flow meter is arranged in the second pipeline, and the flow meter is located between the second flow regulating mechanism and the inlet of the steam drum;

[0018] The second controller is electrically connected to the flow meter and the third flow regulating mechanism, respectively, and is used for receiving the actual flow of the deoxygenated water in the second pipeline sent by the flow meter, and controlling the third flow regulating mechanism to adjust the flow of the deoxygenated water sent into the deaerator through the third pipeline according to the actual flow, so that the flow of the deoxygenated water sent out by the heat exchange mechanism matches the flow of the deoxygenated water sent into the heat exchange mechanism.

[0019] Optionally, the first flow regulating mechanism includes a water pump;

[0020] The second flow regulating mechanism includes: a first opening valve;

[0021] The third flow regulating mechanism includes: a second opening valve.

[0022] Optionally, the second flow regulating mechanism further includes:

[0023] A first on-off mechanism is located between the inlet of the drum and the first opening valve;

[0024] A second on-off mechanism is located between the outlet of the heat exchange mechanism and the first opening valve;

[0025] The third flow regulating mechanism also includes:

[0026] A third on-off mechanism is located between the inlet of the deaerator and the second opening valve;

[0027] The fourth on-off mechanism is located between the outlet of the heat exchange mechanism and the second opening valve.

[0028] Optionally, the waste heat recovery system also includes:

[0029] A fifth on-off mechanism, wherein the fifth on-off mechanism and the second flow regulating mechanism are arranged in parallel between the inlet of the steam drum and the outlet of the heat exchange mechanism;

[0030] The sixth on-off mechanism and the third flow regulating mechanism are arranged in parallel between the inlet of the deaerator and the outlet of the heat exchange mechanism.

[0031] Optionally, the heat exchange mechanism includes:

[0032] A heat exchanger, wherein the inlet of the heat exchanger is connected to the outlet of the first pipeline, and the outlet of the heat exchanger is respectively connected to the inlet of the second pipeline and the inlet of the third pipeline;

[0033] a seventh on-off mechanism, located between the inlet of the heat exchanger and the first flow regulating mechanism;

[0034] The eighth on-off mechanism is located between the outlet of the heat exchanger and the inlet of the second pipeline, and between the outlet of the heat exchanger and the inlet of the third pipeline.

[0035] Optionally, also include:

[0036] The fourth pipeline has an inlet connected to the outlet of the first pipeline, and an outlet connected to the inlets of the second pipeline and the third pipeline respectively;

[0037] The ninth on-off mechanism is arranged on the fourth pipeline.

[0038] In a second aspect, a waste heat recovery method is provided, which is applied to the waste heat recovery system in the first aspect. The waste heat recovery method comprises:

[0039] Controlling the deoxygenated water in the first pipeline to enter the heat exchange mechanism at a flow rate greater than a set threshold;

[0040] regulating the flow rate of deoxygenated water fed into the drum through the second pipeline;

[0041] The flow rate of the deoxygenated water sent into the deaerator through the third pipeline is adjusted so that the flow rate of the deoxygenated water sent out of the heat exchange mechanism is equal to the flow rate of the deoxygenated water sent into the heat exchange mechanism.

[0042] In a third aspect, a drum water supply system is provided, comprising a drum, a deaerator, and the waste heat recovery system of the first aspect connected to the drum and the deaerator.

[0043] The technical solution provided by this application has at least the following technical effects or advantages:

[0044] The waste heat recovery system, method and drum water replenishment system provided by the present application, on the one hand, sends the deoxygenated water output by the deaerator into the heat exchange mechanism through the first pipeline to absorb the waste heat in the flue of the heating furnace. The flow rate of the deoxygenated water entering the heat exchange mechanism is controlled by the first flow regulating mechanism to ensure full utilization of the flue waste heat, avoid too little deoxygenated water and vaporization, resulting in insufficient water replenishment of the drum. On the other hand, part of the deoxygenated water after heat exchange is supplemented to the drum through the second pipeline, and the other part is sent back to the deaerator through the third pipeline. When the amount of water replenishment required by the drum is small, the flow of the third pipeline is controlled by the third flow control mechanism to increase, so as to ensure that the amount of deoxygenated water passing through the heat exchange mechanism is kept above the set threshold, thereby avoiding too little deoxygenated water passing through the heat exchange mechanism. The water replenishment of the drum is difficult, and the heat exchange of the heat exchange mechanism is guaranteed, so that the flue waste heat can be quickly released, and the safe operation of the waste heat recovery system is guaranteed.

[0045] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0047] Figure 1 It is a schematic diagram of drum water replenishment in the prior art;

[0048] Figure 2 The waste heat recovery system structure in the embodiment of this application Figure 1 ;

[0049] Figure 3 The waste heat recovery system structure in the embodiment of this application Figure 2 ;

[0050] Figure 4 The waste heat recovery system structure in the embodiment of this application Figure 3 ;

[0051] Figure 5 This is a flow chart of the waste heat recovery method in the embodiment of this application;

[0052] Figure 6 It is a wireframe diagram of the drum water supply system in the embodiment of the present application. DETAILED DESCRIPTION

[0053] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings.

[0054] Various structural schematic diagrams according to embodiments of the present application are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may further design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0055] In order to better understand the above-mentioned technical scheme, the above-mentioned technical scheme will be described in detail below in combination with specific implementation methods. It should be understood that the embodiments of the present disclosure and the specific features in the embodiments are detailed descriptions of the technical scheme of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0056] In the metallurgical industry, the heating furnace is the first process of the hot rolling production line. The performance of the heated slab directly affects the slab rolling process and the quality of the finished product. With the increasing demand for efficient and low-energy development of heating furnaces, making full use of flue gas waste heat is a requirement for low-carbon energy conservation.

[0057] In order to fully utilize the waste heat of flue gas, the existing technology designs a waste heat utilization system and integrates it into the original vaporization cooling system, such as Figure 1 As shown, the waste heat utilization device 101 arranged in the flue of the heating furnace is connected to the water supply pipeline 103 of the drum 102 to heat the water in the waste heat recovery. During operation, the amount of water supply required by the drum 102 determines the amount of water in the water supply pipeline 103. When the amount of water supply of the drum 102 is low, the water in the water supply pipeline 103 vaporizes when passing through the waste heat utilization device 101, resulting in a low outlet pressure of the feed water pump 104 arranged on the water supply pipeline 103 and a steam blockage problem, making it difficult to supply water to the drum 102, and also seriously affecting the stable operation of the original vaporization cooling system. After the water in the water supply pipeline 103 vaporizes, the pressure fluctuation in the waste heat utilization device 101 becomes larger, which poses a greater safety risk and is not conducive to the safe operation of the waste heat utilization system.

[0058] In view of this, this application provides a waste heat recovery system, please refer to Figure 1 , Figure 1 This is a structural diagram of the waste heat recovery system in the embodiment of the present application, including: a heat exchange mechanism 201, which is arranged in the flue of the heating furnace;

[0059] The first pipeline 202 has an inlet connected to the outlet of the deaerator 203 and an outlet connected to the inlet of the heat exchange mechanism 201;

[0060] The second pipeline 204 has an inlet connected to the outlet of the heat exchange mechanism 201 and an outlet connected to the inlet of the steam drum 205;

[0061] The third pipeline 206 has an inlet connected to the outlet of the heat exchange mechanism 201 and an outlet connected to the inlet of the deaerator 203;

[0062] A first flow regulating mechanism 207, disposed in the first pipeline 202, for controlling the deoxygenated water in the first pipeline 202 to enter the heat exchange mechanism 201 at a flow rate greater than a set threshold;

[0063] A second flow regulating mechanism 208 is provided in the second pipeline 204 and is used to regulate the flow of the deoxygenated water fed into the steam drum 205 through the second pipeline 204;

[0064] The third flow regulating mechanism 209 is arranged in the third pipeline 206 and is used to regulate the flow of deoxygenated water sent into the deaerator 203 through the third pipeline 206 so that the flow of deoxygenated water sent out by the heat exchange mechanism 201 matches the flow of deoxygenated water sent into the heat exchange mechanism 201.

[0065] The waste heat recovery system provided in the embodiment of the present application, on the one hand, sends the deoxygenated water outputted from the deaerator 203 to the heat exchange mechanism 201 through the first pipeline 202 to absorb the waste heat in the flue of the heating furnace. The flow rate of the deoxygenated water entering the heat exchange mechanism 201 is controlled by the first flow regulating mechanism 207 to ensure full utilization of the flue waste heat, and to avoid too little deoxygenated water passing through the heat exchange mechanism 201 and vaporization, resulting in insufficient water replenishment of the steam drum 205. On the other hand, part of the deoxygenated water after heat exchange is replenished to the steam drum 205 via the second pipeline 204, and the other part is sent back to the deaerator 203 via the third pipeline 206. When the amount of water replenishment required for the steam drum 205 is small, the flow of the third pipeline 206 is controlled to increase by the third flow control mechanism to ensure that the amount of deoxygenated water passing through the heat exchange mechanism 201 is maintained above the set threshold, thereby avoiding insufficient vaporization of the deoxygenated water passing through the heat exchange mechanism 201, resulting in difficulty in replenishing water to the steam drum 205, while ensuring the heat exchange capacity of the heat exchange mechanism 201, so that the flue waste heat can be quickly released, and at the same time ensuring the safe operation of the waste heat recovery system.

[0066] It is understandable that the function of the deaerator 203 is to remove oxygen from the water. The third pipeline 206 can be used to return the deoxygenated water that is not used by the boiler drum 205 to the deaerator 203, but it is not the only water source for the deaerator 203. Since the deaerator 203 needs to continuously supply deoxygenated water to the boiler drum 205, the inlet of the deaerator 203 also needs to be connected to the water source, and water is supplied to the deaerator 203 through the water source to ensure the water replenishment of the boiler drum 205.

[0067] The following specific embodiments are used to describe in detail the technical solution of the present application and how the technical solution of the present application solves the above technical problems. The following specific embodiments can be implemented independently or in combination with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0068] In some optional embodiments, such as Figure 3 As shown, the waste heat recovery system provided in the embodiment of the present application also includes

[0069] Liquid level gauge 301, arranged on drum 205;

[0070] The first controller 302 is electrically connected to the liquid level meter 301 and the second flow regulating mechanism 208, respectively, and is used to receive the actual liquid level of the drum 205 sent by the liquid level meter 301, and control the second flow regulating mechanism 208 to adjust the flow of the deoxygenated water sent to the drum 205 through the second pipeline 204 according to the actual liquid level. The first controller 302 automatically controls the second flow regulating mechanism 208 to adjust the flow of the second pipeline 204 through the signal sent by the liquid level meter 301, so as to ensure that the liquid level of the drum 205 is constant.

[0071] In some optional embodiments, Figure 3 As shown, the waste heat recovery system also includes:

[0072] A flow meter 303 is provided in the second pipeline 204, and the flow meter 303 is located between the second flow regulating mechanism 208 and the inlet of the steam drum 205;

[0073] The second controller 304 is electrically connected to the flow meter 303 and the third flow regulating mechanism 209, respectively, and is used for receiving the actual flow of the deoxygenated water in the second pipeline 204 sent by the flow meter 303, and controlling the third flow regulating mechanism 209 to adjust the flow of the deoxygenated water sent into the deaerator 203 through the third pipeline 206 according to the actual flow, so that the flow of the deoxygenated water sent out by the heat exchange mechanism 201 matches the flow of the deoxygenated water sent into the heat exchange mechanism 201.

[0074] In some optional embodiments, such as Figure 4 As shown, the first flow regulating mechanism 207 includes a water pump 401; the second flow regulating mechanism 208 includes: a first opening valve 402. The first controller 302 is electrically connected to the first opening valve 402, and adjusts the opening of the first opening valve 402 according to the actual liquid level of the drum 205 to adjust the flow of the deoxygenated water sent to the drum 205 through the second pipeline 204.

[0075] The third flow regulating mechanism 209 includes: a second opening valve 403. The second controller 304 is electrically connected to the second opening valve 403, and controls the second opening valve 403 to adjust the flow of the deoxygenated water sent to the deaerator 203 through the third pipeline 206, so that the flow of the deoxygenated water sent out by the heat exchange mechanism 201 matches the flow of the deoxygenated water sent into the heat exchange mechanism 201.

[0076] The pressure of the drum 205 is usually 0.9 MPa, and the pressure of the deaerator 203 is usually 0.02 MPa. For example, when the flow rate of deoxygenated water in the first pipeline 202 is maintained at a value greater than a set threshold, when the water replenishment flow rate required by the drum 205 is lower than the set Q1, the second controller 304 controls the second opening valve 403 to open to a larger opening V1, thereby increasing the flow rate of the third pipeline to meet the water replenishment demand of the drum 205 while ensuring that the flow rate of deoxygenated water delivered by the heat exchange mechanism matches the flow rate of deoxygenated water delivered to the heat exchange mechanism, thereby ensuring that the amount of deoxygenated water passing through the heat exchange mechanism is sufficient, and avoiding the deoxygenated water from vaporizing when passing through the heat exchange mechanism due to too low a flow rate, resulting in insufficient water replenishment to the drum, and steam blockage caused by low outlet pressure of the water pump 401.

[0077] When the water replenishment flow required by the drum 205 is higher than Q1, the second controller 304 controls the second opening valve 403 to open to a smaller opening V2, where V2 is smaller than V1, to reduce the flow of the third pipeline to ensure the flow of the first pipeline.

[0078] Since the pressure of the deaerator 203 is much lower than the pressure of the steam drum 205, most of the deoxygenated water output by the heat exchange mechanism will return to the deaerator 203 through the third pipeline 206, and a small part will be supplemented to the steam drum 205 through the second pipeline 204, so as to realize the circulation of the deoxygenated water between the heat exchange mechanism 201 and the deaerator 203. In this way, the water supply in the heat exchange mechanism 201 can be guaranteed without being affected by the water replenishment of the steam drum 205, and at the same time, the flow rate of the deoxygenated water in the first pipeline 202 can be maintained at a value greater than the set threshold value, so as to avoid the water in the first pipeline 202 from evaporating too little and causing the water pump 401 to be blocked by steam, and unable to supply water to the steam drum 205.

[0079] In some optional embodiments, Figure 4 As shown, the second flow regulating mechanism 208 also includes:

[0080] The first on-off mechanism 404 is located between the inlet of the drum 205 and the first opening valve 402 ; the second on-off mechanism 405 is located between the outlet of the heat exchange mechanism 201 and the first opening valve 402 .

[0081] When the first opening valve 402 needs to be repaired or replaced, the first on-off mechanism 404 and the second on-off mechanism 405 are disconnected to prevent the deoxygenated water in the second pipeline 204 from leaking.

[0082] The third flow regulating mechanism 209 also includes:

[0083] The third on-off mechanism 406 is located between the inlet of the deaerator 203 and the second opening valve 403 ; the fourth on-off mechanism 407 is located between the outlet of the heat exchange mechanism 201 and the second opening valve 403 .

[0084] When the second opening valve 403 needs to be repaired or replaced, the third on-off mechanism 406 and the fourth on-off mechanism 407 are disconnected to prevent the deoxygenated water in the third pipeline 206 from leaking.

[0085] In some optional embodiments, Figure 4 As shown, the waste heat recovery system also includes:

[0086] The fifth on-off mechanism 408 and the second flow regulating mechanism 208 are arranged in parallel between the inlet of the steam drum 205 and the outlet of the heat exchange mechanism 201 .

[0087] When the first opening valve 402 of the second flow regulating mechanism 208 needs to be repaired or replaced, the first on-off mechanism 404 and the second on-off mechanism 405 are disconnected, and the fifth on-off mechanism 408 is opened. Water is added to the boiler drum 205 through the parallel branch where the fifth on-off mechanism 408 is located to ensure the normal operation of the boiler drum 205.

[0088] The sixth on-off mechanism 409 and the third flow regulating mechanism 209 are arranged in parallel between the inlet of the deaerator 203 and the outlet of the heat exchange mechanism 201 .

[0089] When the second opening valve 403 of the third flow regulating mechanism 209 needs to be repaired or replaced, the third on-off mechanism 406 and the fourth on-off mechanism 407 are disconnected, and the sixth on-off mechanism 409 is opened, and the deoxygenated water delivered by the heat exchange mechanism is delivered to the deaerator 203 through the parallel branch where the sixth on-off mechanism 409 is located, to ensure that the amount of deoxygenated water passing through the heat exchange mechanism remains above the set threshold.

[0090] In some optional embodiments, Figure 4 As shown, the heat exchange mechanism 201 includes:

[0091] The heat exchanger 410 has an inlet connected to the outlet of the first pipeline 202, and the outlet of the heat exchanger 410 is respectively connected to the inlet of the second pipeline 204 and the inlet of the third pipeline 206. The seventh on-off mechanism 411 is located between the inlet of the heat exchanger 410 and the first flow regulating mechanism 207. The eighth on-off mechanism 412 is located between the outlet of the heat exchanger 410 and the inlet of the second pipeline 204, and between the outlet of the heat exchanger 410 and the inlet of the third pipeline 206.

[0092] The heat exchanger 410 is arranged in the flue of the heating furnace, and utilizes the waste heat of the flue gas in the flue to heat the deoxygenated water sent from the first pipeline 202. When the heat exchanger 410 needs to be repaired or replaced, the seventh on-off mechanism 411 and the eighth on-off mechanism 412 are disconnected to prevent the deoxygenated water in the first pipeline 202 from leaking.

[0093] In some optional embodiments, Figure 4 As shown, the waste heat recovery system further includes: a ninth on-off mechanism 413 , which is arranged in parallel with the heat exchange mechanism in the first pipeline 202 .

[0094] When the heat exchanger 410 of the heat exchange mechanism 201 needs to be repaired or replaced, the seventh on-off mechanism 411 and the eighth on-off mechanism 412 are disconnected, and the ninth on-off mechanism 413 is opened. Water is supplied to the second pipeline and the third pipeline through the parallel branch where the ninth on-off mechanism 413 is located to ensure the normal operation of the boiler drum 205.

[0095] Based on the same inventive concept, the present application also provides a waste heat recovery method, which is applied to any waste heat recovery system provided in the above embodiments, such as Figure 5 As shown, the waste heat recovery method includes:

[0096] S501. Control the deoxygenated water in the first pipeline to enter the heat exchange mechanism at a flow rate greater than a set threshold.

[0097] S502. Regulate the flow rate of deoxygenated water fed into the steam drum through the second pipeline.

[0098] S503, adjusting the flow rate of the deoxygenated water sent into the deaerator through the third pipeline so that the flow rate of the deoxygenated water sent out of the heat exchange mechanism is equal to the flow rate of the deoxygenated water sent into the heat exchange mechanism.

[0099] The waste heat utilization method provided in the embodiment of the present application, on the one hand, sends the deoxygenated water output by the deaerator into the heat exchange mechanism through the first pipeline to absorb the waste heat in the flue of the heating furnace. The flow rate of the deoxygenated water entering the heat exchange mechanism is controlled by the first flow regulating mechanism to ensure full utilization of the flue waste heat, avoid too little deoxygenated water and vaporization, resulting in insufficient water replenishment of the drum. On the other hand, part of the deoxygenated water after heat exchange is supplemented to the drum through the second pipeline, and the other part is sent back to the deaerator through the third pipeline. When the amount of water replenishment required by the drum is small, the flow of the third pipeline is controlled by the third flow control mechanism to increase, so as to ensure that the amount of deoxygenated water passing through the heat exchange mechanism is kept above the set threshold, thereby avoiding too little deoxygenated water passing through the heat exchange mechanism and causing difficulty in replenishing the drum, while ensuring the heat exchange capacity of the heat exchange mechanism, so that the flue waste heat can be quickly released, and at the same time ensuring the safe operation of the waste heat recovery system.

[0100] Based on the same inventive concept, the embodiment of the present application also provides a drum water supply system, such as Figure 6As shown, the drum water supply system 600 includes a drum 601, a deaerator 602, and a waste heat recovery system 603 connected to the drum 601 and the deaerator 602, wherein the specific structure of the waste heat recovery system 603 is as shown in the above embodiment and will not be described again here.

[0101] The drum water supply system provided in the embodiment of the present application adopts the waste heat recovery system 603 shown in the above embodiment, and sends the deoxygenated water output by the deaerator 602 to the heat exchange mechanism 201 through the first pipeline 202 to absorb the waste heat in the flue of the heating furnace. The flow rate of the deoxygenated water entering the heat exchange mechanism 201 is controlled by the first flow regulating mechanism 207 to ensure full utilization of the flue waste heat, and to avoid the deoxygenated water passing through the heat exchange mechanism 201 too little and vaporizing, resulting in insufficient water replenishment of the drum 601. On the other hand, part of the deoxygenated water after heat exchange is replenished to the steam drum 601 through the second pipeline 204, and the other part is sent back to the deaerator 602 through the third pipeline 206. When the amount of water replenishment required for the steam drum 601 is small, the flow of the third pipeline 206 is controlled to increase by the third flow control mechanism to ensure that the amount of deoxygenated water passing through the heat exchange mechanism 201 is maintained above the set threshold, thereby avoiding insufficient vaporization of the deoxygenated water passing through the heat exchange mechanism 201, resulting in difficulty in replenishing water to the steam drum 601, and at the same time ensuring the heat exchange capacity of the heat exchange mechanism 201, so that the flue waste heat can be quickly released, and at the same time ensuring the safe operation of the waste heat recovery system 603.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, 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 embodiments of the present application.

[0103] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

Claims

1. A waste heat recovery system, characterized in that: include: A heat exchange mechanism is arranged in the flue of the heating furnace; A first pipeline, the inlet of which is connected to the outlet of the deaerator, and the outlet of which is connected to the inlet of the heat exchange mechanism; A second pipeline, the inlet of which is connected to the outlet of the heat exchange mechanism, and the outlet of which is connected to the inlet of the steam drum; A third pipeline, an inlet of which is connected to the outlet of the heat exchange mechanism, and an outlet of which is connected to the inlet of the deaerator; A first flow regulating mechanism, disposed in the first pipeline, for controlling the deoxygenated water in the first pipeline to enter the heat exchange mechanism at a flow rate greater than a set threshold; a second flow regulating mechanism, disposed in the second pipeline, for regulating the flow of deoxygenated water fed into the steam drum through the second pipeline; The third flow regulating mechanism is arranged in the third pipeline and is used to regulate the flow of deoxygenated water sent into the deaerator through the third pipeline so that the flow of deoxygenated water sent out by the heat exchange mechanism matches the flow of deoxygenated water sent into the heat exchange mechanism.

2. The waste heat recovery system according to claim 1, characterized in that: The waste heat recovery system also includes: A liquid level gauge, arranged on the steam drum; The first controller is electrically connected to the liquid level meter and the second flow regulating mechanism, respectively, and is used to receive the actual liquid level of the steam drum sent by the liquid level meter, and control the second flow regulating mechanism to adjust the flow of deoxygenated water sent into the steam drum through the second pipeline according to the actual liquid level.

3. The waste heat recovery system according to claim 1, characterized in that: The waste heat recovery system also includes: a flow meter, disposed in the second pipeline, the flow meter being located between the second flow regulating mechanism and the inlet of the steam drum; The second controller is electrically connected to the flow meter and the third flow regulating mechanism, respectively, and is used for receiving the actual flow of the deoxygenated water in the second pipeline sent by the flow meter, and controlling the third flow regulating mechanism to adjust the flow of the deoxygenated water sent into the deaerator through the third pipeline according to the actual flow, so that the flow of the deoxygenated water sent out by the heat exchange mechanism matches the flow of the deoxygenated water sent into the heat exchange mechanism.

4. The waste heat recovery system according to claim 1, characterized in that: The first flow regulating mechanism comprises a water pump; The second flow regulating mechanism includes: a first opening valve; The third flow regulating mechanism includes: a second opening valve.

5. The waste heat recovery system according to claim 4, characterized in that: The second flow regulating mechanism also includes: a first on-off mechanism, located between the inlet of the drum and the first opening valve; a second on-off mechanism, located between the outlet of the heat exchange mechanism and the first opening valve; The third flow regulating mechanism also includes: a third on-off mechanism, located between the inlet of the deaerator and the second opening valve; The fourth on-off mechanism is located between the outlet of the heat exchange mechanism and the second opening valve.

6. The waste heat recovery system according to claim 1, characterized in that: The waste heat recovery system also includes: a fifth on-off mechanism, wherein the fifth on-off mechanism and the second flow regulating mechanism are arranged in parallel between the inlet of the drum and the outlet of the heat exchange mechanism; A sixth on-off mechanism, wherein the sixth on-off mechanism and the third flow regulating mechanism are arranged in parallel between the inlet of the deaerator and the outlet of the heat exchange mechanism.

7. The waste heat recovery system according to claim 1, characterized in that: The heat exchange mechanism comprises: a heat exchanger, wherein the inlet of the heat exchanger is connected to the outlet of the first pipeline, and the outlet of the heat exchanger is respectively connected to the inlet of the second pipeline and the inlet of the third pipeline; a seventh on-off mechanism, located between the inlet of the heat exchanger and the first flow regulating mechanism; The eighth on-off mechanism is located between the outlet of the heat exchanger and the inlet of the second pipeline, and between the outlet of the heat exchanger and the inlet of the third pipeline.

8. The waste heat recovery system according to claim 7, characterized in that: Also includes: a fourth pipeline, the inlet of which is connected to the outlet of the first pipeline, and the outlet of which is respectively connected to the inlets of the second pipeline and the third pipeline; The ninth on-off mechanism is arranged on the fourth pipeline.

9. A waste heat recovery method, characterized in that: Applied to the waste heat recovery system according to any one of claims 1 to 8, the waste heat recovery method comprises: Controlling the deoxygenated water in the first pipeline to enter the heat exchange mechanism at a flow rate greater than a set threshold; regulating the flow rate of deoxygenated water fed into the drum through the second pipeline; The flow rate of the deoxygenated water sent into the deaerator through the third pipeline is adjusted so that the flow rate of the deoxygenated water sent out of the heat exchange mechanism is equal to the flow rate of the deoxygenated water sent into the heat exchange mechanism.

10. A drum water supply system, characterized in that: It comprises a steam drum, a deaerator and a waste heat recovery system as claimed in any one of claims 1 to 8 connected to the steam drum and the deaerator.

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