Flue gas total heat recovery system, heating system and control method

Abstract

This invention discloses a flue gas total heat recovery system, a heating system, and a control method. The heating system includes at least two boilers. The flue gas total heat recovery system includes a waste heat recovery impeller module and a control module. The waste heat recovery impeller module includes a waste heat recovery impeller device and a centrifugal fan. The flue gas outlet of the waste heat recovery impeller device is connected to the centrifugal fan. The flue gas inlet of each waste heat recovery impeller device is connected to the flue gas outlet of each boiler. An electrically controlled valve is installed on the connecting pipe between each waste heat recovery impeller device and the boiler flue gas outlet. The control module is used to collect the operating time of each waste heat recovery impeller device and to control the opening and closing of all electrically controlled valves according to the operating time to balance the operating time of all waste heat recovery impeller devices. This invention can achieve efficient flue gas heat and moisture recovery from boilers, automate the control of boiler waste heat recovery, facilitate equipment maintenance, and extend the service life of the equipment.

Description

Technical Field

[0001] This invention relates to a flue gas total heat recovery system, a heating system, and a control method. Background Technology

[0002] As the capital of China, Beijing considers achieving carbon neutrality a crucial goal in planning its future high-quality development and building a world-class, harmonious, and livable capital. Heating is one of the city's largest end-use energy consumption sectors, and implementing a revolution in its heating energy structure plays a decisive role in achieving Beijing's carbon neutrality goal by 2050.

[0003] A boiler is an energy conversion device that inputs the chemical energy and electrical energy from fuel into the boiler, and outputs steam, high-temperature water or organic heat carriers after combustion and conversion.

[0004] A boiler consists of two main parts: the boiler itself and the furnace. The boiler refers to the container, while the furnace is the place where fuel is burned. The steam or hot water produced by the boiler can directly provide the heat energy needed for industrial production and people's lives, or it can be converted into mechanical energy through a steam power unit. A generator can then use this mechanical energy to produce electrical energy.

[0005] With the increasing national requirements for the energy efficiency and safety of special equipment, the drawbacks of traditional production control models are becoming increasingly prominent. Issues such as low boiler room safety, high energy consumption, and high operating costs urgently require improvement through the transformation of production monitoring platforms. Based on these factors, research is needed on boiler room renovation to meet the boiler room's load requirements while using appropriate technical means to achieve the goals of improving production efficiency, reasonably reducing energy consumption, and enhancing boiler room safety and other safety standards.

[0006] Waste heat recovery technology used in other fields can be applied to the field of smart boilers, such as the dehumidification system used in the fresh air treatment process of the spraying environment with patent number CN201820822230.X.

[0007] In the existing technology, the flue gas heat and moisture recovery device is installed one-to-one with the boiler, which is inconvenient for maintenance and has a short service life. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology where the flue gas heat and moisture recovery device and the boiler are installed in a one-to-one manner, which is inconvenient to maintain and has a short service life. The present invention provides a flue gas total heat recovery system, heating system and control method that can realize efficient flue gas heat and moisture recovery of boiler, realize automated control of waste heat recovery of boiler, facilitate equipment maintenance and improve equipment service life.

[0009] The present invention solves the above-mentioned technical problems through the following technical solution:

[0010] A flue gas total heat recovery system is provided for use in a heating system, the heating system comprising at least two boilers. The system is characterized in that it includes several waste heat recovery impeller modules and a control module. Each waste heat recovery impeller module includes a waste heat recovery impeller device and a corresponding centrifugal fan. The flue gas outlet of the waste heat recovery impeller device is connected to the corresponding centrifugal fan. The flue gas inlet of each waste heat recovery impeller device is connected to the flue gas outlet of each boiler. An electrically controlled valve is installed on the connecting pipe between each waste heat recovery impeller device and the boiler flue gas outlet. The control module is connected to each electrically controlled valve. The control module is used to collect the operating time of each waste heat recovery impeller device and to control the start and stop of all electrically controlled valves based on the operating time to balance the operating time of all waste heat recovery impeller devices.

[0011] Preferably, the flue gas total heat recovery system further includes an interconnection device, which includes the same number of exhaust pipes as the boiler and the same number of inlet pipes as the waste heat recovery rotor device. The exhaust pipes are arranged side by side, with one end connected to the boiler and the other end connected to the chimney. The inlet pipes are arranged side by side and connected to the inlet of the waste heat recovery rotor device. Each exhaust pipe has the same number of through holes as the inlet pipes and is connected to all the inlet pipes by connecting pipes installed through the through holes. Each connecting pipe is equipped with one of the electrically controlled valves.

[0012] Preferably, the smoke inlet pipe is located above or below the smoke exhaust pipe, and the projections of the smoke inlet pipe and the smoke exhaust pipe on the horizontal plane are perpendicular to each other.

[0013] Preferably, the control module is used for:

[0014] Determine whether to start a waste heat recovery rotor module. If so, start the waste heat recovery rotor module with the shortest running time according to the running time.

[0015] Preferably, the control module is used to acquire the fresh air inlet temperature, rotor speed and centrifugal fan speed of the waste heat recovery rotor device, and the control module is also used to control the rotor speed and centrifugal fan speed according to the boiler operating parameters;

[0016] The control module is also used to determine whether the currently operating waste heat recovery rotor module meets the power requirements of all boilers based on the boiler operating parameters; otherwise, a waste heat recovery rotor module is started.

[0017] Preferably, the control module is further configured to:

[0018] Obtain the total power of all currently operating boilers. Calculate the minimum number of operating waste heat recovery turbine modules using the total power and the maximum load of the waste heat recovery turbine modules. Determine if the current number of operating waste heat recovery turbine modules is greater than the minimum number. If so, shut down one waste heat recovery turbine module and adjust the allocation of the current total load among the operating waste heat recovery turbine modules.

[0019] Preferably, the control module is further configured to:

[0020] The rotor speed and centrifugal fan speed are obtained based on the total power of all currently operating boilers and the fresh air inlet temperature of the waste heat recovery rotor device.

[0021] The start and stop of all electrically controlled valves are controlled according to the power difference between currently operating boilers to balance the waste heat recovery resources matched to the boilers. The waste heat recovery resources are provided through the waste heat recovery impeller module.

[0022] Preferably, the control module is further configured to:

[0023] For any two operating boilers, each boiler corresponds to a waste heat recovery rotor module. The power values ​​of the two boilers are obtained, and it is determined whether the power value of one boiler is greater than the power value of the other boiler by a preset multiple. If so, the waste heat recovery rotor modules corresponding to the two boilers provide waste heat recovery resources for the boiler with the larger power value, and only one waste heat recovery rotor module provides waste heat recovery resources for the boiler with the smaller power value.

[0024] The present invention also provides a heating system, characterized in that the heating system includes the flue gas total heat recovery system as described above.

[0025] The present invention also provides a control method, characterized in that the control method is used to control the flue gas total heat recovery system as described above.

[0026] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0027] The positive and progressive effects of this invention are as follows:

[0028] This invention enables efficient flue gas heat and moisture recovery from boilers, automates the control of waste heat recovery from boilers, facilitates equipment maintenance, and extends the service life of the equipment. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the heating system according to Embodiment 1 of the present invention.

[0030] Figure 2 This is a schematic diagram of the interconnection device according to Embodiment 1 of the present invention.

[0031] Figure 3 This is a flowchart of the control method of Embodiment 1 of the present invention. Detailed Implementation

[0032] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein. Example

[0033] See Figure 1 and Figure 2 This embodiment provides a heating system, which includes several boilers and a flue gas total heat recovery system.

[0034] The flue gas total heat recovery system includes several waste heat recovery rotor modules and a control module. The control module can be a control terminal such as a computing server or desktop computer.

[0035] In this embodiment, there are 3 boilers 11 and 3 waste heat recovery rotor modules 21. This embodiment is only used to more clearly explain the connection relationship between the boilers and the waste heat recovery rotor modules, and does not mean that the number of boilers needs to be the same as the number of waste heat recovery rotor modules.

[0036] Each waste heat recovery rotor module includes a waste heat recovery rotor device and a corresponding centrifugal fan.

[0037] The flue gas outlet of the waste heat recovery rotor is connected to the corresponding centrifugal fan.

[0038] The inlet of each waste heat recovery rotor is connected to the outlet of each boiler.

[0039] Each waste heat recovery rotor is equipped with an electrically controlled valve on the connecting pipe between the waste heat recovery rotor and the boiler flue gas outlet.

[0040] The control module is connected to each electrically controlled valve.

[0041] The control module is used to collect the operating time of each waste heat recovery rotor device, and the control module is used to control the start and stop of all electrically controlled valves according to the operating time to balance the usage time of all waste heat recovery rotor devices.

[0042] See Figure 2 The flue gas total heat recovery system also includes an interconnection device 31.

[0043] The interconnection device includes the same number of exhaust pipes 311 as the boiler and the same number of inlet pipes 312 as the waste heat recovery rotor device. The exhaust pipes are arranged side by side, with one end of the exhaust pipe 311 connected to the boiler and the other end connected to the chimney 313.

[0044] The flue gas inlet pipes are arranged side by side and connected to the flue gas inlet of the waste heat recovery rotor device.

[0045] Each row of flue pipes has the same number of through holes 314 as the number of flue pipes, and the connecting pipes installed through the through holes are connected to all the flue pipes.

[0046] Each connecting pipe is equipped with one of the aforementioned electrically controlled valves 315.

[0047] The smoke inlet pipe is located above or below the smoke exhaust pipe, and the projections of the smoke inlet pipe and the smoke exhaust pipe on the horizontal plane are perpendicular to each other.

[0048] The flue gas total heat recovery system also includes a fresh air interconnection device. The air blown out of the fresh air outlet of the waste heat recovery rotor module is heated, and the heated fresh air enters the air inlet of the boiler after passing through the fresh air interconnection device.

[0049] The control module is used for:

[0050] Determine whether to start a waste heat recovery rotor module. If so, start the waste heat recovery rotor module with the shortest running time according to the running time.

[0051] The control module is used to acquire the fresh air inlet temperature, rotor speed and centrifugal fan speed of the waste heat recovery rotor device. The control module is also used to control the rotor speed and centrifugal fan speed according to the boiler operating parameters and the fresh air inlet temperature of the waste heat recovery rotor device.

[0052] The control module is also used to determine whether the currently operating waste heat recovery rotor module meets the power requirements of all boilers based on the boiler operating parameters; otherwise, a waste heat recovery rotor module is started.

[0053] The control module is also used for:

[0054] Obtain the total power of all currently operating boilers. Calculate the minimum number of operating waste heat recovery turbine modules using the total power and the maximum load of the waste heat recovery turbine modules. Determine if the current number of operating waste heat recovery turbine modules is greater than the minimum number. If so, shut down one waste heat recovery turbine module and adjust the allocation of the current total load among the operating waste heat recovery turbine modules.

[0055] Specifically, when the number of currently operating waste heat recovery rotor modules is greater than or equal to 2 compared to the minimum number of operating modules, one waste heat recovery rotor module is shut down and the operating waste heat recovery rotor modules are adjusted to divide the current total load.

[0056] The control module is also used for:

[0057] The rotor speed and centrifugal fan speed are obtained based on the total power of all currently operating boilers and the fresh air inlet temperature of the waste heat recovery rotor device.

[0058] The start and stop of all electrically controlled valves are controlled according to the power difference between currently operating boilers to balance the waste heat recovery resources matched to the boilers. The waste heat recovery resources are provided through the waste heat recovery impeller module.

[0059] The control module is also used for:

[0060] For any two operating boilers, each boiler corresponds to a waste heat recovery rotor module to obtain the power values ​​of the two boilers;

[0061] Determine whether the power value of one boiler is greater than that of another boiler by a preset multiple (0.75 times in this embodiment). If so, the waste heat recovery rotor modules corresponding to both boilers will provide waste heat recovery resources for the boiler with the larger power value, and only one waste heat recovery rotor module will provide waste heat recovery resources for the boiler with the smaller power value.

[0062] See Figure 2 The power ratings of the first boiler, the second boiler, and the third boiler are 3a, 2a, and a, respectively. The control module determines the power ratings as follows:

[0063] For the first boiler and the third boiler, if the power of the first boiler is 3 times that of the third boiler, which is greater than 1.75 times, then the first boiler occupies the waste heat recovery resources of the third boiler, and opens the No. 1, No. 7 and No. 9 electric control valves. The third boiler does not occupy the waste heat recovery resources of the first boiler, and closes the No. 3 electric control valve.

[0064] For the second boiler and the third boiler, if the power of the second boiler is twice that of the third boiler (more than 1.75 times), then the second boiler will occupy the waste heat recovery resources of the third boiler, and the No. 5, No. 8 and No. 9 electric control valves will be opened. The third boiler will not occupy the waste heat recovery resources of the second boiler, and the No. 6 electric control valve will be closed.

[0065] For the first boiler and the second boiler, if the power of the first boiler is 1.5 times that of the second boiler but less than 1.75 times, then the first boiler does not occupy the waste heat recovery resources of the second boiler, and the No. 4 electric control valve is closed.

[0066] See Figure 3 In addition to the above-mentioned flue gas total heat recovery system, this embodiment also provides a control method, including:

[0067] Step 100: The control module collects the running time of each waste heat recovery rotor device;

[0068] Step 101: The control module controls the start and stop of all electrically controlled valves according to the running time to balance the usage time of all waste heat recovery rotor devices.

[0069] The smoke inlet pipe is located above or below the smoke exhaust pipe, and the projections of the smoke inlet pipe and the smoke exhaust pipe on the horizontal plane are perpendicular to each other.

[0070] Step 101 includes:

[0071] Determine whether to start a waste heat recovery rotor module. If so, start the waste heat recovery rotor module with the shortest running time according to the running time.

[0072] Further, step 101 includes:

[0073] The control module acquires the fresh air inlet temperature, rotor speed, and centrifugal fan speed of the waste heat recovery rotor device. The control module is also used to control the rotor speed and centrifugal fan speed according to the boiler operating parameters and the fresh air inlet temperature of the waste heat recovery rotor device.

[0074] The control module determines whether the currently operating waste heat recovery rotor module meets the power requirements of all boilers based on the boiler operating parameters; otherwise, it starts a waste heat recovery rotor module.

[0075] Further, step 101 includes:

[0076] Obtain the total power of all currently operating boilers. Calculate the minimum number of operating waste heat recovery turbine modules using the total power and the maximum load of the waste heat recovery turbine modules. Determine if the current number of operating waste heat recovery turbine modules is greater than the minimum number. If so, shut down one waste heat recovery turbine module and adjust the allocation of the current total load among the operating waste heat recovery turbine modules.

[0077] Furthermore, step 101 also includes:

[0078] The rotor speed and centrifugal fan speed are obtained based on the total power of all currently operating boilers and the fresh air inlet temperature of the waste heat recovery rotor device.

[0079] The start and stop of all electrically controlled valves are controlled according to the power difference between currently operating boilers to balance the waste heat recovery resources matched to the boilers. The waste heat recovery resources are provided through the waste heat recovery impeller module.

[0080] Further, step 101 includes:

[0081] For any two operating boilers, each boiler corresponds to a waste heat recovery rotor module. The power values ​​of the two boilers are obtained, and it is determined whether the power value of one boiler is greater than the power value of the other boiler by a preset multiple. If so, the waste heat recovery rotor modules corresponding to the two boilers provide waste heat recovery resources for the boiler with the larger power value, and only one waste heat recovery rotor module provides waste heat recovery resources for the boiler with the smaller power value.

[0082] The functions in step 101 can be operated in parallel or sequentially according to the time sequence. If the judgment result is negative, the operation returns to the beginning of the time sequence and is operated again to achieve the corresponding function.

[0083] The terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the 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.

[0084] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A flue gas total heat recovery system for a heating system, the heating system comprising at least two boilers, characterized in that, The flue gas total heat recovery system comprises a plurality of waste heat recovery runner modules and a control module, each waste heat recovery runner module comprises a waste heat recovery runner device and a corresponding centrifugal fan, the smoke outlet of the waste heat recovery runner device is connected with the corresponding centrifugal fan, the smoke inlet of each waste heat recovery runner device is connected with the smoke outlet of each boiler, an electric control valve is arranged on the connecting pipeline of each waste heat recovery runner device and the boiler smoke outlet, the control module is connected with each electric control valve, the control module is used for collecting the running time length of each waste heat recovery runner device, and the control module is used for controlling the start and stop of all electric control valves according to the running time length to balance the use time length of all waste heat recovery runner devices. The flue gas total heat recovery system further comprises an intercommunication device, the intercommunication device comprises a plurality of smoke exhaust pipes which are arranged in parallel and are connected with the boilers and a plurality of smoke inlet pipes which are arranged in parallel and are connected with the waste heat recovery runner devices, each smoke exhaust pipe is provided with a plurality of through holes which are connected with all smoke inlet pipes through connecting pipes, and each connecting pipe is provided with an electric control valve. The smoke inlet pipe is arranged above or below the smoke exhaust pipe, and the projections of the smoke inlet pipe and the smoke exhaust pipe on the horizontal plane are perpendicular to each other. The control module is used for: judging whether to start a waste heat recovery runner module, and if yes, starting the waste heat recovery runner module with the shortest running time length of the waste heat recovery runner device according to the running time length.

2. The flue gas total heat recovery system of claim 1, wherein, The control module is used for obtaining the fresh air inlet temperature of the waste heat recovery runner device, the runner rotating speed and the centrifugal fan rotating speed, and the control module is further used for controlling the runner rotating speed and the centrifugal fan rotating speed according to the boiler operating parameters. The control module is further used for judging whether the currently running waste heat recovery runner module meets the power of all boilers according to the boiler operating parameters, and if not, starting a waste heat recovery runner module.

3. The flue gas total heat recovery system of claim 1, wherein, The control module is further used for: obtaining the total power of all currently running boilers, calculating the minimum running number of the waste heat recovery runner module by using the total power and the maximum load of the waste heat recovery runner module, judging whether the running number of the current waste heat recovery runner module is greater than the minimum running number, and if yes, closing one waste heat recovery runner module and adjusting the current total load of the running waste heat recovery runner module.

4. The flue gas total heat recovery system of claim 1, wherein, The control module is further used for: obtaining the runner rotating speed and the centrifugal fan rotating speed according to the total power of all currently running boilers and the fresh air inlet temperature of the waste heat recovery runner device; controlling the start and stop of all electric control valves according to the power difference between the currently running boilers to balance the waste heat recovery resources matched with the boilers, wherein the waste heat recovery resources are provided by the waste heat recovery runner module.

5. The flue gas total heat recovery system of claim 4, wherein, The control module is further used for: For any two running boilers, each corresponding to a waste heat recovery turbine module, the power values of the two boilers are obtained, and it is judged whether the power value of one boiler is greater than the power value of the other boiler by a preset multiple, if yes, the waste heat recovery turbine modules corresponding to the two boilers both provide waste heat recovery resources for the boiler with the greater power value, and only one waste heat recovery turbine module provides waste heat recovery resources for the boiler with the smaller power value.

6. A heating system, characterized by The heating system comprises the flue gas total heat recovery system according to any one of claims 1 to 5.

7. A control method characterized by, The control method is used for controlling the flue gas total heat recovery system according to any one of claims 1 to 5.

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