A control method for a steam energy-saving heating system

Abstract

The present invention provides a control method for an energy-saving steam heating system, comprising a first heating mode and a second heating mode. The second heating mode comprises: B1: controlling the material to be heated in the heating pipeline to first exchange heat with a hot water heat exchanger, heating the material to a temperature of W1; B2: controlling the material to be heated in the heating pipeline to then exchange heat with a steam heat exchanger, heating the material to a temperature of W2, where W2 is greater than W1. By recycling condensed water from the steam heat exchanger and switching between different heating modes based on temperature and liquid level detection, the overall adaptability and energy utilization of the system are improved, steam consumption is reduced, heating time is shortened, and the heating efficiency of the energy-saving steam heating system is enhanced.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of energy conservation and utilization, and in particular to a control method for a steam energy-saving heating system. Background Art

[0002] With the increasing severity of energy problems and people's attention to living environment, clean energy and full utilization of energy are particularly important. Steam is widely used as a clean and renewable resource. For example, in dehumidification systems, the regeneration zone of the dehumidification wheel often uses steam as a heating source for heating and desorption.

[0003] However, the existing steam heating device has a low utilization rate. After one heat exchange, a large amount of heat energy is directly discharged, resulting in waste and increasing energy costs. The direct discharge of condensed water generated by steam heating is not only a waste of energy, but also increases environmental pollution. There is no effective control method in the existing technology to recycle the remaining heat energy of steam. Therefore, an effective and simple control method is urgently needed to solve these problems. Summary of the Invention

[0004] The present invention solves the problems in the prior art of low steam utilization rate, resulting in energy waste, energy waste caused by direct discharge of condensed water generated by steam, being unfriendly to the environment, and slow steam heating efficiency.

[0005] The present invention provides a control method for a steam energy-saving heating system. The system includes a hot water heat exchanger, a steam heat exchanger, a steam main pipe, a connecting pipe, a water outlet pipe, a water return pipe, and a heating pipe. The steam main pipe is used to input steam into the steam heat exchanger. Condensed water generated by the steam heat exchanger flows into the hot water heat exchanger through the connecting pipe. The condensed water of the hot water heat exchanger is discharged through the water outlet pipe. The water return pipe is provided between the hot water heat exchanger and the steam heat exchanger. The heating pipe sequentially connects the hot water heat exchanger and the steam heat exchanger. The control method includes a second heating mode, which includes:

[0006] B1: Control the material to be heated in the heating pipeline to exchange heat with the hot water heat exchanger first, and the temperature of the material to be heated is heated to W1;

[0007] B2: Control the material to be heated in the heating pipeline to exchange heat with the steam heat exchanger, and the temperature of the material to be heated is heated to W2, W2>W1.

[0008] Preferably, the control method further includes: a first heating mode before heating in the second heating mode, wherein the first heating mode includes:

[0009] A1: Control the steam to enter the steam heat exchanger through the steam main pipe, and control the electric stop valve in the water outlet pipeline to be in the closed state;

[0010] A2: Control the heat exchange between the material to be heated in the heating pipeline and the steam heat exchanger;

[0011] A3: Control the condensed water generated by the steam heat exchanger to enter the hot water heat exchanger through the connecting pipe and accumulate.

[0012] Preferably, the first heating mode further comprises:

[0013] S1: When condensed water accumulates in the hot water heat exchanger, the liquid level sensor in the water outlet pipe is controlled to detect whether there is condensed water;

[0014] S2: When the liquid level sensor detects condensed water, the electric stop valve on the water outlet pipe is controlled to open, and then enters the second heating mode.

[0015] Preferably, the second heating mode further comprises:

[0016] B3: Control the second thermometer on the connecting pipeline to detect the temperature. When the temperature detected by the second thermometer is higher than a preset value, control the variable frequency pump on the return pipeline to increase the flow rate of condensed water in the return pipeline into the connecting pipeline, and / or control to reduce the amount of steam input into the steam main pipe.

[0017] Preferably, the second heating mode further comprises:

[0018] B4: Control the temperature detected by the first thermometer on the water outlet pipe. When the temperature detected by the first thermometer is higher than a preset value, lower the preset value of the second thermometer and / or reduce the amount of steam input to the steam main pipe.

[0019] Preferably, the first heating mode includes:

[0020] A4: Control the steam to enter the steam heat exchanger through the steam main pipe, and control the variable frequency pump on the connecting pipeline to be in the off state;

[0021] A5: Control the heat exchange between the material to be heated in the heating pipeline and the steam heat exchanger;

[0022] A6: The condensed water generated by the steam heat exchanger is controlled to enter the water tank through the connecting pipe and accumulate.

[0023] Preferably, the first heating mode further comprises:

[0024] S4: Controlling the liquid level sensor in the water tank to detect whether the condensed water reaches a preset liquid level;

[0025] S5: When the liquid level sensor in the water tank detects that the condensed water reaches a preset liquid level, the variable frequency pump is controlled to start, the condensed water in the water tank is filled into the hot water heat exchanger, and then the second heating mode is entered.

[0026] Preferably, the second heating mode further comprises:

[0027] B5: Control the second thermometer on the connecting pipe to detect the temperature W3, and control the third thermometer to detect the inlet temperature W4 of the heating pipe;

[0028] B6: When W3>W4, the electric regulating valve in the return pipe is controlled to open, and the electric stop valve in the outlet pipe is controlled to close;

[0029] B7: Control the condensed water flowing out of the hot water heat exchanger to flow back into the water tank through the return pipe and enter the circulation;

[0030] B8: Control loop until W3=W4;

[0031] B9: When W3=W4, the electric regulating valve in the return water pipeline is controlled to close, and the electric stop valve in the outlet water pipeline is controlled to open;

[0032] B10: Control the draining of condensed water in the hot water heat exchanger and the draining of condensed water in the water tank;

[0033] B11: Re-enter the first heating mode.

[0034] Preferably, the control method further includes:

[0035] controlling the fourth thermometer to detect the outlet temperature of the heating pipe;

[0036] When the temperature detected by the fourth thermometer is higher than the preset value, the proportional control valve at the steam main pipe is controlled to reduce the steam input;

[0037] When the temperature detected by the fourth thermometer is lower than the preset value, the proportional control valve at the steam main pipe is controlled to increase the steam input.

[0038] The beneficial effects of the present invention are as follows: by reusing steam thermal energy, the utilization rate of energy is improved and waste is reduced; the secondary heating method is adopted to improve the working efficiency of the steam heating system and shorten the heating time; the control method used in the present invention has a wide range of applications and takes into account the different amounts of condensed water generated by the steam heat exchanger; the most appropriate working mode is selected according to the different detected temperatures and liquid levels, thereby improving the overall adaptability and energy utilization rate of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of a steam energy-saving heating system according to a first embodiment of the present invention;

[0040] Figure 2 The steps of the first heating mode of the first embodiment of the present invention;

[0041] Figure 3This is a step for stabilizing the operation of the hot water heat exchanger according to the first embodiment of the present invention;

[0042] Figure 4 This is a step of detecting the second thermometer on the connecting pipe according to the first embodiment of the present invention;

[0043] Figure 5 This is a step of detecting a first thermometer on the water outlet pipe according to the first embodiment of the present invention;

[0044] Figure 6 A schematic diagram of a steam energy-saving heating system according to a second embodiment of the present invention;

[0045] Figure 7 The steps of the first heating mode of the second embodiment of the present invention;

[0046] Figure 8 This is a step for stabilizing the operation of the hot water heat exchanger according to the second embodiment of the present invention;

[0047] Figure 9 This is a step of detecting the second thermometer on the connecting pipe and the third thermometer on the heating pipe according to the second embodiment of the present invention.

[0048] In the figure,

[0049] 1. Steam energy-saving heating system; 2. First heating section; 3. Second heating section; 4. Connecting pipeline; 5. Heating pipeline; 6. Steam main pipe; 7. Water outlet pipeline; 8. Liquid level sensor; 9. Electric stop valve; 10. Safety valve; 11. Return water pipeline; 12. Second thermometer; 13. Frequency conversion pump; 14. First thermometer; 15. Electric regulating valve; 16. Water tank; 17. Third thermometer; 18. Proportional regulating valve; 19. Fourth thermometer. DETAILED DESCRIPTION

[0050] The present invention is described in detail below with reference to the accompanying drawings. The description in this section is only exemplary and explanatory and should not have any limiting effect on the scope of protection of the present invention.

[0051] Figure 1 It is a schematic diagram of a steam energy-saving heating system 1 according to a first embodiment of the present invention. In this embodiment, the steam energy-saving heating system 1 includes a first heating part 2, a second heating part 3 connected to the first heating part 2 via a connecting pipe 4, a heating pipe 5, and a return water pipe 11.

[0052] The first heating part 2 is a hot water heat exchanger, and the second heating part 3 is a steam heat exchanger. The input end of the steam heat exchanger is connected to a steam main pipe 6, and steam is input into the steam heat exchanger through the steam main pipe 6. The condensed water generated by the steam heat exchanger flows into the hot water heat exchanger through the connecting pipe 4. The output end of the hot water heat exchanger is connected to a water outlet pipe 7 for discharging the condensed water inside the hot water heat exchanger. The water outlet pipe 7 contains a liquid level sensor 8, an electric stop valve 9, a safety valve 10, and a first thermometer 14.

[0053] The heating pipeline 5 is connected with the first heating part 2 and the second heating part 3 in sequence. The material to be heated first flows into the first heating part 2, then flows out of the first heating part 2 and flows into the second heating part 3. When flowing out of the second heating part 3, the material to be heated has been heated to a preset temperature. A fourth thermometer 19 is provided at the outlet end of the heating pipeline 5, and a proportional regulating valve 18 is provided on the steam main pipe 6. When the fourth thermometer 19 detects temperature fluctuations, the control device controls the proportional regulating valve 18 to adjust the steam input amount.

[0054] Condensed water from the hot water heat exchanger is re-injected into the connecting pipe 4 through the return pipe 11, allowing the condensed water to be recycled. A second thermometer 12 is installed on the connecting pipe 4 and preset to the required temperature. A variable frequency pump 13 is installed on the return pipe 11. The operating frequency of the variable frequency pump 13 is controlled by temperature changes to adjust the condensed water flow in the return pipe 11.

[0055] In this embodiment, the control method of the steam energy-saving heating system 1 includes the following steps: Figure 2 :

[0056] In the first procedure, the material to be heated is heated through the heating pipe 5 in a first heating mode. The first heating mode includes:

[0057] A1: Control the steam to enter the steam heat exchanger through the steam main pipe 6, and control the electric stop valve 9 in the water outlet pipe 7 to be in the closed state;

[0058] A2: Control the heat exchange between the material to be heated in the heating pipeline 5 and the steam heat exchanger;

[0059] A3: Control the condensed water generated by the steam heat exchanger to enter the hot water heat exchanger through the connecting pipe 4 and accumulate.

[0060] When the system is just started, it operates in the first heating mode. Only the steam heat exchanger and the material to be heated are exchanging heat. There is no condensed water in the hot water heat exchanger and the system has not reached the working state. In order to accumulate condensed water, the electric stop valve 9 in the outlet pipe 7 is in the closed state.

[0061] In the second procedure, the hot water heat exchanger operates stably, and the control method of the steam energy-saving heating system 1 includes the following steps: Figure 3 :

[0062] S1: When condensed water accumulates in the hot water heat exchanger, the liquid level sensor 8 in the water outlet pipe 7 is controlled to detect whether there is condensed water;

[0063] S2: When the liquid level sensor 8 detects condensed water, the electric stop valve 9 on the water outlet pipe 7 is controlled to open, and then the second heating mode is entered.

[0064] During the operation of the first heating mode, the hot water heat exchanger initially has insufficient condensate, and the electric shut-off valve 9 is closed. As the steam heat exchanger continuously feeds condensate into the hot water heat exchanger, the condensate in the hot water heat exchanger accumulates and becomes saturated until it flows into the outlet pipe 7. The outlet pipe 7 includes a liquid level sensor 8 and an electric shut-off valve 9. The liquid level sensor 8 detects the liquid level in the outlet pipe 7, and the electric shut-off valve 9 controls the opening and closing of the outlet pipe 7. When the liquid level sensor 8 detects that the liquid level in the outlet pipe 7 reaches a preset value, the control device outputs a feedback signal and controls the opening of the electric shut-off valve 9 to drain the condensate from the hot water heat exchanger. At this point, the hot water heat exchanger operates stably and enters the second heating mode. During this process, the pressure in each pipe of the steam energy-saving heating system 1 fluctuates continuously. To ensure the safety of the system, a safety valve 10 can also be configured to relieve pressure if the pressure is too high (above 0.6 MPa).

[0065] In the third procedure, the material to be heated is heated through the heating pipe 5 in the second heating mode. The second heating mode includes the following steps:

[0066] B1: Control the material to be heated in the heating pipe 5 to first exchange heat with the hot water heat exchanger, and the temperature is heated to W1;

[0067] B2: Control the material to be heated in the heating pipeline 5 to exchange heat with the steam heat exchanger again, and the temperature is heated to W2, W2>W1.

[0068] The second heating mode also includes the step of detecting the temperature with the second thermometer 12 on the connecting pipe 4. Figure 4 :

[0069] B3: Control the second thermometer 12 on the connecting pipe 4 to detect the temperature. When the temperature detected by the second thermometer 12 is higher than a preset value, control the variable frequency pump 13 on the return pipe 11 to increase the flow rate of condensed water in the return pipe 11 flowing into the connecting pipe 4, and / or control to reduce the amount of steam input into the steam main pipe 6.

[0070] The condensed water has the highest temperature when it flows out of the steam heat exchanger, and its temperature drops after circulating through the pipeline. Therefore, the temperature of the condensed water in the return pipe 11 is lower than the temperature of the condensed water in the connecting pipe 4. When the second thermometer 12 detects that the temperature in the connecting pipe 4 is higher than the preset value, the signal is fed back to the variable frequency pump 13, and the condensed water with lower temperature discharged from the hot water heater flows back into the connecting pipe 4 through the return pipe 11 to reduce the temperature in the connecting pipe 4. The condensed water flowing from the connecting pipe 4 through the hot water heat exchanger and then flowing back to the connecting pipe 4 from the return pipe 11 is called a local small circulation. The beneficial effect of this is to ensure the stability of the condensed water temperature input to the hot water heater, thereby improving the stability and controllability of the heating temperature of the hot water heater, and then adjusting the steam amount input to the steam main pipe 6, reducing the steam consumption, and reducing energy consumption. The stability of the local small circulation also improves the stability of the overall circulation and reduces the damage of the condensed water to the equipment.

[0071] The second heating mode also includes the step of detecting the temperature with the first thermometer 14 on the water outlet pipe 7, such as Figure 5 :

[0072] B4: Control the temperature detected by the first thermometer 14 on the water outlet pipe 7. When the temperature detected by the first thermometer 14 is higher than a preset value, lower the preset value of the second thermometer 12 and / or reduce the amount of steam input to the steam main pipe 6.

[0073] A first thermometer 14 is provided on the water outlet pipe 7 to detect the temperature of the discharged condensed water. When the discharge temperature is higher than a preset value, the preset temperature of the second thermometer 12 is adjusted accordingly, and the local small circulation is adjusted, thereby reducing the amount of steam input into the steam main pipe 6, reducing the amount of steam used, and reducing energy consumption, so that the temperature discharged from the water outlet pipe 7 approaches the temperature at the input end of the heating pipe 5. When the input temperature of the heating pipe 5 is the ambient temperature, the temperature discharged from the steam energy-saving heating system 1 approaches the ambient temperature. This has the beneficial effect of maximizing the reduction of damage to the environment and minimizing the waste of energy.

[0074] Figure 6 This is a schematic diagram of the steam energy-saving heating system 1 of the second embodiment of the present invention. This embodiment is a further optimization based on the first embodiment, and the same parts are not repeated here. In this embodiment, the connecting pipe 4 is provided with a water tank 16, a variable frequency pump 13, and a second thermometer 12, the heating pipe 5 is provided with a third thermometer 17, and the return pipe 11 is provided with an electric regulating valve 15. One end of the return pipe 11 is connected to the outlet pipe 7, and the other end is connected to the water tank 16.

[0075] In this embodiment, the control method of the steam energy-saving heating system 1 includes the following steps: Figure 7 :

[0076] In the first procedure, the material to be heated is heated through the heating pipe 5 in a first heating mode. The first heating mode includes:

[0077] A4: Control the steam to enter the steam heat exchanger through the steam main pipe 6, and control the variable frequency pump 13 on the connecting pipe 4 to be in the off state;

[0078] A5: Controls the heat exchange between the material to be heated in heating pipeline 5 and the steam heat exchanger;

[0079] A6: The condensed water generated by the steam heat exchanger is controlled to enter the water tank 16 through the connecting pipe 4 and accumulate.

[0080] When the system is just started, it operates in the first heating mode. Only the steam heat exchanger and the material to be heated exchange heat. The condensed water flowing out of the steam heat exchanger first flows into the water tank 16. In order to accumulate the condensed water, the variable frequency pump 13 in the connecting pipe 4 is in the closed state.

[0081] The second procedure is to stabilize the operation of the hot water heat exchanger, which includes the following steps: Figure 8 :

[0082] S3: Control the liquid level sensor 8 in the water tank 16 to detect whether the condensed water reaches a preset liquid level;

[0083] S4: When the liquid level sensor 8 in the water tank 16 detects that the condensed water reaches a preset liquid level, the variable frequency pump 13 is controlled to start, and the condensed water in the water tank 16 is filled into the hot water heat exchanger, and then the second heating mode is entered.

[0084] As the first heating mode continues to operate, the condensed water in the water tank 16 continues to accumulate until it is saturated. When the liquid level sensor 8 in the water tank 16 detects that the condensed water in the water tank 16 reaches a preset liquid level, the signal is fed back to the control device. The control device controls the variable frequency pump 13 to start, and the condensed water in the water tank 16 is input into the hot water heat exchanger through the variable frequency pump 13. After the hot water heat exchanger is filled with condensed water, it starts to work stably.

[0085] In the third procedure, the material to be heated is heated through the heating pipe 5 in the second heating mode. The second heating mode includes the following steps:

[0086] B1: Control the material to be heated in the heating pipe 5 to first exchange heat with the hot water heat exchanger, and the temperature is heated to W1;

[0087] B2: Control the material to be heated in the heating pipeline 5 to exchange heat with the steam heat exchanger again, and the temperature is heated to W2, W2>W1.

[0088] The second heating mode also includes the steps of detecting the temperature W3 on the connecting pipe 4 by the second thermometer 12 and detecting the inlet temperature W4 of the heating pipe 5 by the third thermometer 17. Figure 9 :

[0089] B5: Control the second thermometer 12 on the connecting pipe 4 to detect the temperature W3, and control the third thermometer 17 to detect the inlet temperature W4 of the heating pipe 5;

[0090] B6: When W3>W4, the electric regulating valve 15 in the return water pipeline 11 is controlled to open, and the electric stop valve 9 in the outlet water pipeline 7 is controlled to close;

[0091] B7: Control the condensed water flowing out of the hot water heat exchanger to flow back into the water tank 16 through the return pipe 11 and enter the circulation;

[0092] B8: Control loop until W3=W4;

[0093] B9: When W3=W4, the electric regulating valve 15 in the return water pipe 11 is controlled to be closed, and the electric stop valve 9 in the outlet water pipe 7 is controlled to be open;

[0094] B10: Control the draining of condensed water in the hot water heat exchanger and the draining of condensed water in the water tank 16;

[0095] B11: Re-enter the first heating mode.

[0096] When entering the second heating mode, the hot water heat exchanger is just filled with the condensed water in the water tank 16. At this time, the temperature in the hot water heat exchanger is the highest. The temperature W3 detected by the second thermometer 12 is higher than the temperature W4 detected by the third thermometer 17, that is, W3>W4. The hot water heat exchanger can be used to exchange heat with the material to be heated in the heating pipeline 5. In order to make full use of the heat energy in the hot water heat exchanger, the condensed water is recycled. The electric regulating valve 15 in the return pipe 11 is opened, and the electric stop valve 9 in the outlet pipe 7 is closed. The condensed water flowing out of the hot water heat exchanger flows back into the water tank 16 through the return pipe 11 and enters the circulation. As the circulation progresses, The temperature of the condensed water in the hot water heat exchanger continues to decrease, and after flowing into the water tank 16, the temperature of the condensed water in the water tank 16 also continues to decrease. This cycle continues until the temperature detected by the second thermometer 12 is equal to the temperature detected by the third thermometer 17, that is, W3=W4. At this time, the hot water heat exchanger can no longer play a heating role, the electric regulating valve 15 in the return pipe 11 is closed, and the electric stop valve 9 in the outlet pipe 7 is opened. The condensed water in the hot water heat exchanger is emptied, the condensed water in the water tank 16 is emptied, and the system re-enters the first heating mode. The water tank 16 starts to accumulate condensed water again, and the steam energy-saving heating system 1 starts a new cycle.

[0097] The beneficial effect of the control method in this embodiment is that, instead of giving preset values ​​to the second thermometer 12 and the third thermometer 17, the detection values ​​of the two are compared. The second thermometer 12 detects the temperature of the condensed water entering the hot water heat exchanger, and the third thermometer 17 detects the temperature of the material to be heated. As long as the temperature W3 detected by the second thermometer 12 is higher than the temperature W4 detected by the third thermometer 17, that is, W3>W4, the hot water heat exchanger can provide a certain heating function. Therefore, the electric regulating valve 15 in the return water pipeline 11 is opened, and the electric stop valve 9 in the outlet water pipeline 7 is closed, and the condensed water is continuously recycled until the temperature W3 detected by the second thermometer 12 is equal to the temperature W4 detected by the third thermometer 17. The detected temperature is W4, that is, W3=W4. At this time, the hot water heat exchanger can no longer provide the heating function, the electric regulating valve 15 in the return water pipe 11 is closed, and the electric stop valve 9 in the outlet water pipe 7 is opened. The condensed water in the hot water heat exchanger is drained, and the condensed water in the water tank 16 is drained. This maximizes the thermal energy utilization rate of the condensed water, thereby reducing the amount of steam input to the steam main pipe 6, reducing the amount of steam used, and reducing energy consumption. If the input temperature of the heating pipe 5 is the ambient temperature, and the temperature discharged from the steam energy-saving heating system 1 is close to the ambient temperature, the damage to the environment is minimized. The control method in this embodiment is particularly suitable for the situation where the steam heat exchanger in the system does not generate much condensed water.

[0098] Regardless of which embodiment, the control method of the steam energy-saving heating system 1 further includes the step of detecting the outlet temperature of the heating pipeline 5 with a fourth thermometer 19:

[0099] When the temperature detected by the fourth thermometer 19 is higher than the preset value, the proportional control valve 18 at the steam main pipe 6 is controlled to reduce the steam input;

[0100] When the temperature detected by the fourth thermometer is lower than the preset value, the proportional regulating valve 18 at the steam main pipe 6 is controlled to increase the steam input.

[0101] In order to ensure the stability of the output temperature of the heating pipeline 5, a fourth thermometer is set at the output end of the heating pipeline 5. According to the changes in the detected temperature of the fourth thermometer, the proportional control valve 18 continuously adjusts the amount of steam input from the steam main pipe 6 to the steam heat exchanger. The beneficial effect is that it not only ensures the stability of the output temperature, but also saves steam consumption, reduces energy consumption, and saves costs.

[0102] In the present invention, the first heating mode and the second heating mode can be switched between each other. Whether the condensed water in the hot water heat exchanger and the condensed water in the water tank 16 need to be drained when switching between the modes can be determined based on actual needs. The condensed water draining step in the second embodiment is also applicable to the first embodiment. The condensed water draining step can also be determined by comparing the temperature detected by the second thermometer 12 with the temperature detected by the first thermometer 14 in the first embodiment.

[0103] The present invention has a wide range of application scenarios. Taking the actual application in the lithium battery industry as an example, with the rapid development of new energy and lithium battery markets, a very dry air environment is required in the production process of lithium batteries, which requires the use of a rotary dehumidification system. The rotary regeneration heating energy method in the existing technology currently tends to be steam heating, and the steam consumption is huge, resulting in an increase in cost. The control method of the steam energy-saving heating system 1 of the present invention greatly increases the steam utilization rate and effectively reduces costs.

[0104] It should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0105] The above-described embodiments of the present invention do not limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A control method for a steam energy-saving heating system, characterized in that: The system includes a hot water heat exchanger, a steam heat exchanger, a steam main pipe, a connecting pipe, a water outlet pipe, a water return pipe, and a heating pipe. The steam main pipe is used to input steam into the steam heat exchanger. Condensed water generated by the steam heat exchanger flows into the hot water heat exchanger through the connecting pipe. The condensed water of the hot water heat exchanger is discharged through the water outlet pipe. The water return pipe is provided between the hot water heat exchanger and the steam heat exchanger. The heating pipe sequentially connects the hot water heat exchanger and the steam heat exchanger. The control method includes a second heating mode, which includes: B1: Control the material to be heated in the heating pipeline to exchange heat with the hot water heat exchanger first, and the temperature of the material to be heated is heated to W1; B2: Control the material to be heated in the heating pipeline to exchange heat with the steam heat exchanger, and the temperature of the material to be heated is heated to W2, W2>W1; The control method further includes: a first heating mode before heating in a second heating mode, wherein the first heating mode includes: A1: Control the steam to enter the steam heat exchanger through the steam main pipe, and control the electric stop valve in the water outlet pipeline to be in the closed state; A2: Control the heat exchange between the material to be heated in the heating pipeline and the steam heat exchanger; A3: Control the condensed water generated by the steam heat exchanger to enter the hot water heat exchanger through the connecting pipe and accumulate; The first heating mode further comprises: S1: When condensed water accumulates in the hot water heat exchanger, the liquid level sensor in the water outlet pipe is controlled to detect whether there is condensed water; S2: When the liquid level sensor detects condensed water, the electric stop valve on the outlet pipe is controlled to open, and then enter the second heating mode; The second heating mode also includes: B3: Control the second thermometer on the connecting pipeline to detect the temperature. When the temperature detected by the second thermometer is higher than a preset value, control the variable frequency pump on the return pipeline to increase the flow rate of condensed water in the return pipeline into the connecting pipeline, and / or control to reduce the amount of steam input into the steam main pipe.

2. The control method of the steam energy-saving heating system according to claim 1, characterized in that: The second heating mode further comprises: B4: Control the temperature detected by the first thermometer on the water outlet pipe. When the temperature detected by the first thermometer is higher than a preset value, lower the preset value of the second thermometer and / or reduce the amount of steam input to the steam main pipe.

3. The control method of the steam energy-saving heating system according to claim 1 or 2, characterized in that: The control method further includes: controlling the fourth thermometer to detect the outlet temperature of the heating pipe; When the temperature detected by the fourth thermometer is higher than the preset value, the proportional control valve at the steam main pipe is controlled to reduce the steam input; When the temperature detected by the fourth thermometer is lower than the preset value, the proportional control valve at the steam main pipe is controlled to increase the steam input.

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