Heat conduction oil heating temperature control system and method

Abstract

The embodiment of the invention provides a heat conduction oil heating temperature control system and method. The system comprises a first detection module, a temperature control module, a circulating pump, a waste heat recovery module, a plurality of segmented heat conduction oil pipelines, heating modules corresponding to the heat conduction oil pipelines and a second detection module. The first detection module sends the environment temperature to the temperature control module; the temperature control module calculates the initial heating power corresponding to each heat-conducting oil pipeline, contains the initial heating power in a heating instruction and sends the heating instruction to the corresponding heating module; the circulating pump drives the heat-conducting oil to each heat-conducting oil pipeline; the heating module heats the heat utilization equipment according to the initial heating power; the second detection module sends the heating temperature of the conduction oil pipeline corresponding to the current time period to the temperature control module; the waste heat recovery module calculates the waste heat utilization rate and sends to the temperature control module; and the temperature control module calculates to-be-adjusted heating power required by the next time period, contains the to-be-adjusted heating power in a heating instruction and sends the heating instruction to the corresponding heating module for subsequent heating temperature control, so that the heating temperature control precision of the heat-conducting oil is improved, and the energy consumption is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal oil heating, and in particular to a thermal oil heating temperature control system and method. Background Art

[0002] Thermal oil has been widely used as a heat transfer medium. It has the advantages of uniform heating, high heat transfer efficiency, good thermal stability, and no corrosion to equipment. At present, in production systems, thermal oil can be used as a high-temperature heat carrier to exchange heat with heat-using equipment to play a heating role. In the related art, the heating and temperature control system that uses thermal oil to heat heat-using equipment generally uses a fixed-power electric heater to heat the thermal oil to achieve heating of the heat-using equipment. Specifically, a single-circulation pump is used to drive the flow of thermal oil in the thermal oil pipeline, and an electric heater is used to heat the thermal oil in the thermal oil pipeline with a fixed power to heat the heat-using equipment deployed on the outside of the thermal oil pipeline. However, in this heating and temperature control system, due to the limitation of the flow regulation capability of the single-circulation pump, the thermal inertia of the heating and temperature control system is large, which easily leads to large heating temperature differences in different areas of the heat-using equipment, and relies on the electric heater to operate continuously at a fixed power. The high proportion of ineffective heating makes the overall energy consumption high. Summary of the Invention

[0003] The purpose of the embodiments of the present invention is to provide a thermal oil heating temperature control system and method to improve the accuracy of thermal oil heating temperature control and reduce energy consumption. The specific technical solution is as follows:

[0004] An embodiment of the present invention provides a thermal oil heating and temperature control system, the system comprising: a first detection module, a temperature control module, a circulation pump, a waste heat recovery module, a plurality of segmented thermal oil pipelines and their corresponding heating modules, and a second detection module;

[0005] A first detection module is used to send the detected ambient temperature of the heat-consuming device to the temperature control module;

[0006] The temperature control module is used to send a drive instruction including a rotation speed to the circulation pump; calculate the initial heating power corresponding to each thermal oil pipeline and include it in the heating instruction and send it to the corresponding heating module; send an oil temperature detection instruction to each second detection module;

[0007] Circulation pump, used to drive the thermal oil to each thermal oil pipeline;

[0008] A heating module, used for heating the heat-consuming equipment according to the corresponding initial heating power;

[0009] The second detection module is used to send the heating temperature of the corresponding thermal oil pipeline in the current time period to the temperature control module;

[0010] The waste heat recovery module is used to recover the heat from the heat transfer oil flowing out of each heat transfer oil pipeline, calculate the waste heat utilization rate and send it to the temperature control module;

[0011] The temperature control module is also used to calculate the required adjusted heating power for the next time period based on the waste heat utilization rate, the target temperature of each heat transfer oil pipeline and the heating temperature in the current time period, and include it in the heating instruction and send it to the corresponding heating module for subsequent heating and temperature control.

[0012] Optionally, the system further comprises a thermal oil storage tank;

[0013] The temperature control module is specifically configured to, upon receiving a device heating instruction, send an ambient temperature detection instruction to the first detection module and a drive instruction including a rotational speed to the circulating pump; in response to receiving the ambient temperature sent by the first detection module, calculate the initial heating power of the heating module corresponding to each thermal oil pipeline based on the ambient temperature and the target temperature of each thermal oil pipeline, and send a heating instruction including the initial heating power to the corresponding heating module;

[0014] The heating module is specifically configured to receive the heating instruction including the initial heating power, and heat the thermal oil in the thermal oil pipeline connected thereto according to the initial heating power, so as to heat the heat-consuming equipment outside the corresponding thermal oil pipeline;

[0015] The waste heat recovery module is also used to drive the heat-conducting oil after heat recovery to the heat-conducting oil storage tank;

[0016] The thermal oil storage tank is used to provide thermal oil to each thermal oil pipeline under the drive of the circulation pump, and to recover the thermal oil passing through the waste heat recovery module.

[0017] Optionally, the circulation pump is a multi-stage circulation pump, which includes a parallel main circulation pump and at least one auxiliary circulation pump.

[0018] Optionally, the temperature control module is specifically configured to calculate the initial heating power corresponding to the thermal oil pipeline based on the ambient temperature and the target temperature of the thermal oil pipeline using the following expression:

[0019]

[0020] Among them, P base represents the initial heating power corresponding to the heat transfer oil pipeline, λ represents the thermal conductivity of the heat transfer oil pipeline insulation layer, T set Indicates the target temperature of the thermal oil pipeline, T env Indicates the ambient temperature, D ins Indicates the outer diameter of the thermal oil pipeline insulation layer, D pipe Indicates the outer diameter of the heat-using equipment, Lsegment Indicates the length of the thermal oil pipeline corresponding to the heating equipment.

[0021] Optionally, the waste heat recovery module is specifically configured to calculate the waste heat utilization rate using the following expression:

[0022]

[0023] Q recover =m media ·C media ·(T outmedia -T inmedia );

[0024] Q in =m oil ·C oil ·(T in -T out );

[0025] Among them, η represents the waste heat utilization rate, Q recover Indicates the recovered heat, Q in Indicates the heat of the thermal oil before heat recovery, m media represents the mass flow rate of heat medium in the waste heat recovery module, C media Indicates the specific heat capacity of the heat medium in the waste heat recovery module, T outmedia Indicates the heat medium outlet temperature, T inmedia Indicates the heat medium inlet temperature, m oil represents the mass flow rate of thermal oil at the inlet of the waste heat recovery module, C oil Indicates the specific heat capacity of the heat transfer oil at the inlet of the waste heat recovery module, T in Indicates the oil temperature at the heat exchanger inlet of the waste heat recovery module, T out Indicates the oil temperature at the outlet of the heat exchanger in the waste heat recovery module.

[0026] Optionally, the system further comprises a vibration viscometer, wherein the vibration viscometer is deployed in the thermal oil storage tank;

[0027] The vibration viscometer is used to measure the damping decay time of the vibrator in the heat transfer oil and send the damping decay time to the temperature control module;

[0028] The temperature control module is further configured to receive the damping decay time and calculate the viscosity of the thermal oil in the thermal oil storage tank based on the damping decay time.

[0029] Optionally, the temperature control module is specifically configured to calculate, for each heating module corresponding to each thermal oil pipeline, a heating temperature to be adjusted in the next time period based on the waste heat utilization rate, the viscosity of the thermal oil, the target temperature of the thermal oil pipeline, and the heating temperature of the thermal oil in the thermal oil pipeline in the current time period, using the following expression:

[0030]

[0031] e(t)=T set -T actual ;

[0032] Where u(t) represents the heating temperature to be adjusted in the next time period of the heating module corresponding to the thermal oil pipeline, K p Represents the proportionality coefficient, K i Indicates the integral coefficient, K d represents the differential coefficient, e(t) represents the deviation between the target temperature of the heat transfer oil pipeline and the heating temperature of the heat transfer oil in the heat transfer oil pipeline during the current time period, T set Indicates the target temperature of the thermal oil pipeline, T actual represents the heating temperature of the heat transfer oil in the heat transfer oil pipeline during the current time period, α represents the oil quality attenuation weight, Δμ represents the viscosity change of the heat transfer oil, f(Δμ) represents the viscosity change compensation function, β represents the waste heat recovery weight, and η represents the waste heat utilization rate;

[0033] According to the heating temperature to be adjusted, the corresponding heating power to be adjusted is determined.

[0034] Optionally, the system further includes a third detection module, and the third detection module is deployed in the thermal oil storage tank;

[0035] The third detection module is used to measure the capacitance of the thermal oil in the thermal oil storage tank and send the capacitance to the temperature control module;

[0036] The temperature control module is further used to receive the capacitor and calculate the dielectric constant of the thermal oil in the thermal oil storage tank based on the capacitor, and calculate the aging degree value of the thermal oil according to the viscosity and dielectric constant of the thermal oil in the thermal oil storage tank.

[0037] Optionally, the system further includes a remote monitoring platform;

[0038] The remote monitoring platform is used to send equipment heating instructions and data transmission instructions to the temperature control module, and receive and display the data uploaded by the temperature control module;

[0039] The temperature control module is further configured to upload the heating temperature of each heat transfer oil pipeline, the heating power of the corresponding heating module, and the aging degree value of the heat transfer oil to the remote monitoring platform upon receiving the data transmission instruction.

[0040] An embodiment of the present invention further provides a thermal oil heating and temperature control method, which is applied to any of the thermal oil heating and temperature control systems described above, and the method includes:

[0041] The first detection module sends the detected ambient temperature of the heat-using device to the temperature control module;

[0042] The temperature control module sends a drive instruction including the speed to the circulation pump; calculates the initial heating power corresponding to each thermal oil pipeline and includes it in the heating instruction and sends it to the corresponding heating module; and sends an oil temperature detection instruction to each second detection module;

[0043] The circulation pump drives the thermal oil to each thermal oil pipeline;

[0044] The heating module heats the heat-consuming equipment according to the corresponding initial heating power;

[0045] The second detection module sends the heating temperature of the corresponding thermal oil pipeline in the current time period to the temperature control module;

[0046] The waste heat recovery module recovers the heat from the heat transfer oil flowing out of each heat transfer oil pipeline, calculates the waste heat utilization rate and sends it to the temperature control module;

[0047] The temperature control module calculates the required heating power to be adjusted for the next time period based on the waste heat utilization rate, the target temperature of each heat transfer oil pipeline and the heating temperature in the current time period, and includes it in the heating instruction and sends it to the corresponding heating module for subsequent heating and temperature control.

[0048] Beneficial effects of the embodiments of the present invention:

[0049] The embodiments of the present invention provide a thermal oil heating and temperature control system and method. This system heats heat-consuming equipment through multiple, segmented thermal oil pipelines, further improving heating uniformity for the equipment. Each thermal oil pipeline is individually temperature-controlled. During the heating process, the heating power of the heating modules corresponding to each pipeline is dynamically adjusted based on the waste heat utilization rate of the thermal oil, improving the accuracy of thermal oil heating and temperature control. Furthermore, the dynamic allocation of heating power to the heating modules corresponding to each pipeline during the heating process reduces ineffective heating and, therefore, reduces overall energy consumption.

[0050] Of course, it is not necessary to achieve all of the advantages described above simultaneously in order to implement any product or method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can also be obtained based on these drawings.

[0052] Figure 1A schematic structural diagram of a thermal oil heating and temperature control system provided in an embodiment of the present invention;

[0053] Figure 2 Another structural schematic diagram of a thermal oil heating and temperature control system provided by an embodiment of the present invention;

[0054] Figure 3 A schematic flow chart of a method for heating and controlling the temperature of thermal oil provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field based on this application are within the scope of protection of the present invention.

[0056] In related technologies, a single-circulation pump is used to drive the flow of thermal oil in a thermal oil pipeline, and an electric heater is used to heat the thermal oil in the pipeline at a fixed power level to heat the heat-using equipment deployed outside the pipeline. Limited by the flow regulation capability of the single-circulation pump, the heating and temperature control system has a large thermal inertia, which can easily lead to large temperature differences between different areas of the heating equipment (for example, in scenarios where the heating equipment is a long gas pipeline or multi-zone heating equipment, the temperature difference between the far and near ends may be greater than 10°C). Furthermore, the reliance on the electric heater to continuously operate at a fixed power level can result in ineffective heating accounting for over 40%, resulting in high overall energy consumption.

[0057] In order to improve the temperature control accuracy of thermal oil heating and reduce energy consumption, the embodiment of the present invention provides a thermal oil heating temperature control system and method. The thermal oil heating temperature control system provided by the embodiment of the present invention is as follows: Figure 1 As shown, the thermal oil heating temperature control system 100 includes: a first detection module 101, a temperature control module 102, a circulation pump 103, a waste heat recovery module 107, and a plurality of segmented thermal oil pipelines 104 ( Figure 1 exemplarily shows a thermal oil pipeline) and its corresponding heating module 105 and second detection module 106.

[0058] Among them, the first detection module 101 is connected to the temperature control module 102, the circulation pump 103 is respectively connected to the temperature control module 102 and each thermal oil pipeline 104, the heating module 105 is connected to the corresponding thermal oil pipeline 104 and is connected to the temperature control module 102, the second detection module 106 is placed inside or on the surface of the corresponding thermal oil pipeline 104 and is connected to the temperature control module 102, and the waste heat recovery module 107 is respectively connected to the temperature control module 102 and each thermal oil pipeline 104.

[0059] The first detection module 101 is used to send the detected ambient temperature of the heat-using device to the temperature control module 102;

[0060] The temperature control module 102 is used to send a drive instruction including a rotation speed to the circulation pump 103; calculate the initial heating power corresponding to each thermal oil pipeline 104 and include it in the heating instruction and send it to the corresponding heating module 105; and send an oil temperature detection instruction to each second detection module 106;

[0061] A circulation pump 103 is used to drive the thermal oil to each thermal oil pipeline 104;

[0062] The heating module 105 is used to heat the heat-consuming device according to the corresponding initial heating power;

[0063] The second detection module 106 is used to send the heating temperature of the corresponding thermal oil pipeline in the current time period to the temperature control module 102;

[0064] The waste heat recovery module 107 is used to recover the heat of the thermal oil flowing out of each thermal oil pipeline 104, calculate the waste heat utilization rate and send it to the temperature control module 102;

[0065] The temperature control module 102 is also used to calculate the required heating power to be adjusted for the next time period based on the waste heat utilization rate, the target temperature of each heat transfer oil pipeline 104 and the heating temperature in the current time period, and include it in the heating instruction and send it to the corresponding heating module 105 for subsequent heating and temperature control.

[0066] The thermal oil heating and temperature control system provided by the embodiments of the present invention heats heat-consuming equipment through multiple, segmented thermal oil pipelines. This improves heating uniformity for the heat-consuming equipment, building on the already uniform heating of the thermal oil. Each thermal oil pipeline is individually temperature-controlled. During the heating process, the heating power of the heating module corresponding to each pipeline is dynamically adjusted based on the waste heat utilization rate of the thermal oil, improving the accuracy of thermal oil heating and temperature control. Furthermore, the dynamic allocation of heating power to the heating modules corresponding to each pipeline during the heating process reduces ineffective heating and thus reduces overall energy consumption.

[0067] In the embodiments of the present invention, the heat-using equipment may be any equipment that requires heating, such as a gas pipeline, a reactor, or the like. In scenarios where heat-using equipment is heated using thermal oil, the thermal oil pipeline may be disposed outside the heat-using equipment (for easy understanding, the heat-using equipment is also located outside the thermal oil pipeline, and illustratively, the thermal oil pipeline surrounds the outside of the heat-using equipment). The thermal oil pipeline located outside may transfer heat to the heat-using equipment via a jacket or a heat tracing layer between the thermal oil pipeline and the heat-using equipment, thereby heating the heat-using equipment.

[0068] In one example, before using thermal oil to heat a heat-consuming device, the thermal oil pipeline can be physically or thermodynamically segmented according to the shape and type of the heat-consuming device. Then, the temperature control module controls the heating module connected to the thermal oil pipeline to heat the thermal oil, thereby heating the heat-consuming device outside the thermal oil pipeline and independently controlling the temperature of each section of the thermal oil pipeline.

[0069] For example, physically segmenting the thermal oil pipeline can include: if the heat-consuming equipment is a pipeline (such as a gas pipeline), segmenting the thermal oil pipeline according to the pipeline's length; if the heat-consuming equipment is a device (such as a reactor), segmenting the thermal oil pipeline according to the device's function. For example, if the heat-consuming equipment is a gas pipeline, specifically a DN300 pipeline with a length of 2 km (kilometers), it can be divided into 40 sections using a 50-meter segmentation method. In other words, each of the 40 sections of thermal oil pipeline can be used to heat the corresponding 40 sections of the gas pipeline, with each section independently temperature-controlled to ensure uniform heat load across each section. For another example, if the heat-consuming equipment is a chemical reactor, and the functions of key nodes such as valves or elbows at different heights vary, the reactor can be vertically divided into three sections: bottom, middle, and top. Each section corresponds to a different reaction temperature requirement. Three sections of thermal oil pipeline can then be used to heat the three corresponding sections of the chemical reactor, with each section also independently temperature-controlled.

[0070] Thermodynamic segmentation of the thermal oil pipeline can include: segmenting areas with slower heat diffusion (such as the far end of the gas pipeline) separately, and segmenting high heat dissipation areas (such as overhead sections) and low heat dissipation areas (such as buried sections) separately.

[0071] For each thermal oil pipeline, a temperature acquisition module (i.e., a second detection module) is set inside or on the surface of the thermal oil pipeline. The second detection module can be a PT100 thermal resistor or a fiber grating sensor (with an accuracy of ±0.1°C).

[0072] In one possible implementation, Figure 2 As shown, the thermal oil heating and temperature control system 100 may further include a thermal oil storage tank 108 ; the thermal oil storage tank 108 is connected to the circulation pump 103 and the waste heat recovery module 107 respectively.

[0073] The temperature control module 102 may be specifically configured to send an ambient temperature detection instruction to the first detection module 101 and a drive instruction including a rotational speed to the circulation pump 103 upon receiving a device heating instruction.

[0074] The ambient temperature detection instruction may include a trigger signal for starting ambient temperature detection. The temperature control module 102 may also periodically send a drive instruction including a rotation speed to the circulating pump 103 to periodically adjust the rotation speed of the circulating pump 103 to better adapt to the current heating scenario.

[0075] Correspondingly, the first detection module 101 is specifically configured to receive an ambient temperature detection instruction sent by the temperature control module 102 , monitor the temperature of the environment in which the heat-using device is located, and send the detected ambient temperature to the temperature control module 102 .

[0076] In actual applications, the first detection module 101 can be deployed according to the layout of the heat-using equipment. For example, if the heat-using equipment is outdoors, a first detection module 101 can be set up outdoors; if the heat-using equipment is indoors, a first detection module 101 can be set up indoors; if the heat-using equipment (such as a gas pipeline) passes through both the outdoors and the indoors, a first detection module 101 can be set up indoors and outdoors respectively. Exemplarily, the first detection module 101 can be a thermal resistor for detecting the ambient temperature. The first detection module 101 can send the detected ambient temperature to the temperature control module 102 via RS485 or CAN (Controller Area Network) bus.

[0077] The circulation pump 103 is specifically configured to receive a driving instruction sent by the temperature control module 102 and drive the thermal oil in the thermal oil storage tank 108 to each thermal oil pipeline 104 according to the rotation speed in the driving instruction.

[0078] The thermal oil storage tank 108 is used to provide thermal oil to each thermal oil pipeline 104 under the drive of the circulation pump 103.

[0079] Furthermore, in response to receiving the ambient temperature sent by the first detection module 101, the temperature control module 102 calculates the initial heating power of the heating module 105 corresponding to each thermal oil pipeline 104 based on the ambient temperature and the target temperature of each thermal oil pipeline 104, sends the heating instruction containing the initial heating power to the corresponding heating module 105, and sends the oil temperature detection instruction to each second detection module 106.

[0080] The temperature control module 102 may be a PID (Proportional Integral Derivative) controller, which uses an ARM Cortex-M7 processor as its core and supports multi-channel PID calculations. It outputs a PWM (Pulse Width Modulation) signal to adjust the heating power of the heating modules 105 corresponding to each thermal oil pipeline 104. Exemplarily, the temperature control module 102 sends a heating instruction, including an initial heating power, to the heating modules 105 corresponding to each thermal oil pipeline 104 in the form of a PWM signal. In one example, there may be one or more temperature control modules 102. If there is only one temperature control module 102, it controls the heating of all the heating modules 105 corresponding to the thermal oil pipelines 104. If there are multiple temperature control modules 102, each temperature control module 102 can control the heating of at least one heating module 105 corresponding to the thermal oil pipeline 104, and parameters can be shared between the temperature control modules 102.

[0081] The target temperature of each thermal oil pipeline 104 is the expected / target thermal oil heating temperature pre-set for each thermal oil pipeline 104, which can be the same (such as the same setting for gas pipelines at the same ambient temperature) or different (such as different settings for chemical reactors).

[0082] The temperature control module 102 calculates the initial heating power for each heating module 105 corresponding to each thermal oil pipeline 104 and sends a heating instruction containing the initial heating power to the corresponding heating module 105. The heating module 105 is specifically configured to receive the heating instruction containing the initial heating power and heat the thermal oil within the thermal oil pipeline 104 connected thereto according to the initial heating power, thereby heating the heat-consuming equipment outside the corresponding thermal oil pipeline 104. In one example, the heating module 105 may be a PTC ceramic heater.

[0083] Correspondingly, the second detection module 106 is specifically used to receive the oil temperature detection instruction sent by the temperature control module 102, detect the temperature of the thermal oil in the corresponding thermal oil pipeline 104 according to the temperature detection cycle in the oil temperature detection instruction, and send the heating temperature of the thermal oil in the corresponding thermal oil pipeline 104 detected in the current time period to the temperature control module 102.

[0084] In one example, the oil temperature detection instruction may include an oil temperature detection period and an oil temperature detection frequency. Consequently, the second detection module 106 may detect the temperature of the thermal oil in the corresponding thermal oil pipeline 104 according to the oil temperature detection period and oil temperature detection frequency in the oil temperature detection instruction. The specific oil temperature detection period and oil temperature detection frequency may be set based on actual needs. For example, the oil temperature detection period may be set to 1 millisecond, 1 second, or 1 minute, and the oil temperature detection frequency may be set to 1 millisecond / 2 times, 1 second / 5 times, or 1 minute / 10 times. The second detection module 106 may transmit the heating temperature of the thermal oil in the corresponding thermal oil pipeline 104 detected during the current time period to the temperature control module 102 via RS485 or a CAN bus.

[0085] Considering that the temperature field distribution is affected by multiple factors such as the topology of the heat-using equipment and environmental heat dissipation, and in order to balance local differences and adapt to the dynamic complexity of multi-stage coordinated control, the embodiment of the present invention independently controls the temperature of the heating module 105 corresponding to each thermal oil pipeline 104. During the heating process of the heat-using equipment, the temperature control module 102 receives the heating temperature transmitted by the second detection module 106 corresponding to each thermal oil pipeline 104. For each heating module 105 corresponding to the thermal oil pipeline 104, the temperature control module 102 calculates the required heating power to be adjusted for the next time period based on the waste heat utilization rate, the target temperature of the thermal oil pipeline 104, and the heating temperature of the thermal oil in the thermal oil pipeline 104 during the current time period. The temperature control module 102 then sends a heating instruction containing the required heating power to be adjusted to the corresponding heating module 105 for subsequent heating and temperature control.

[0086] The heat transfer oil flowing out of each heat transfer oil pipeline 104 enters the waste heat recovery module 107, and then the waste heat recovery module 107 recovers the heat of the heat transfer oil flowing out of each heat transfer oil pipeline 104, and can also drive the heat-recovered heat transfer oil (i.e., cold oil) to the heat transfer oil storage tank 108.

[0087] In one example, the waste heat recovery module 107 may include a heat exchanger (such as a plate heat exchanger) and a heat medium circulation loop. The plate heat exchanger is used to exchange heat between the heat transfer oil (i.e., high-temperature return oil, the temperature of which may reach 120-200°C) flowing out of each heat transfer oil pipeline 104 and a refrigerant (such as water or air, etc.) to achieve heat recovery. The heat medium circulation loop includes a heat medium circulation pump, a water storage tank, a temperature control valve, etc. The heat medium circulation pump drives the refrigerant in the water storage tank and the heat transfer oil (cold oil) after heat recovery to flow, and controls the opening and closing of the temperature control valve to transfer the recovered heat to a designated system or purpose, such as for preheating new heat transfer oil, transferring it to a heating system, etc. The waste heat recovery module 107 may also include a heat storage tank to store the recovered heat in the heat storage tank.

[0088] The waste heat recovery module 107 may further include a heat calculation unit for calculating the waste heat utilization rate and sending the waste heat utilization rate to the temperature control module 102, so that the heat medium circuit and the oil circuit are decoupled to avoid mutual interference.

[0089] The thermal oil storage tank 108 is also used to recover the thermal oil (i.e., cold oil) that passes through the waste heat recovery module 107 .

[0090] In an embodiment of the present invention, the waste heat recovery module recovers heat from the thermal oil flowing out of each thermal oil pipeline. The recovered heat (i.e., waste heat) can be used preferentially to preheat new thermal oil or supply heat to other external systems to improve the waste heat utilization rate and thereby improve the overall energy saving rate.

[0091] In a possible implementation, the circulation pump 103 is a multi-stage circulation pump, which includes a parallel main circulation pump and at least one auxiliary circulation pump.

[0092] The main circulation pump provides the base thermal oil flow rate and is driven by a variable frequency motor. The flow rate it provides can be, for example, 200 L / min (liters / minute). The auxiliary circulation pump, or auxiliary fine-tuning circulation pump, is used to dynamically fine-tune the driven thermal oil flow rate. It is connected in parallel to the main circulation pump and can provide a flow rate of, for example, 20% of the main circulation pump flow rate (e.g., 40 L / min). Specifically, the number of auxiliary circulation pumps can be set according to actual needs, and the embodiments of the present invention do not impose specific limitations on this.

[0093] In an embodiment of the present invention, a pressure-flow coupling controller can also be provided for the circulation pump 103. The pressure-flow coupling controller is used to monitor the pressure of each heat transfer oil pipeline in real time, so as to dynamically allocate the speed ratio of the main circulation pump and at least one auxiliary circulation pump according to the monitored pressure, and can expand the flow adjustment range of the auxiliary circulation pump to 0.1% to 100% of the main circulation pump, which is conducive to realizing refined zoning temperature control.

[0094] The use of a multi-stage circulating pump, with a primary circulating pump and at least one auxiliary circulating pump connected in parallel, eliminates the flow regulation bottleneck of a single circulating pump and enables stepless adjustment of the auxiliary circulating pump's flow rate from 0.1% to 100%, facilitating refined temperature control. In the event of a primary circulating pump failure, the auxiliary circulating pump can temporarily take over thermal oil flow control, improving the fault tolerance and reliability of the thermal oil heating and temperature control system. The multi-stage circulating pump design allows for seamless switchover to other circulating pumps in the event of a pump failure, extending maintenance cycles and reducing failure rates.

[0095] In one possible implementation, the temperature control module 102 is specifically configured to calculate the initial heating power corresponding to the thermal oil pipeline 104 based on the ambient temperature and the target temperature of the thermal oil pipeline 104 using the following expression:

[0096]

[0097] Among them, P base represents the initial heating power corresponding to the heat transfer oil pipeline, λ represents the thermal conductivity of the heat transfer oil pipeline insulation layer, T set Indicates the target temperature of the thermal oil pipeline, T env Indicates the ambient temperature, D ins Indicates the outer diameter of the thermal oil pipeline insulation layer, D pipe Indicates the outer diameter of the heat-using equipment, L segment Indicates the length of the thermal oil pipeline corresponding to the heating equipment.

[0098] In one example, the ambient temperature can be the ambient temperature of the heat-consuming equipment associated with the thermal oil pipeline. The initial heating power associated with the thermal oil pipeline refers to the initial heating power of the heating module associated with the thermal oil pipeline. The thermal oil pipeline insulation layer can be directly the outer layer of the thermal oil pipeline or a structural insulation layer on the outer layer of the thermal oil pipeline.

[0099] In an embodiment of the present invention, the initial heating power of the heating module corresponding to the thermal oil pipeline is calculated based on the ambient temperature and the target temperature of the thermal oil pipeline, so that the thermal oil in the thermal oil pipeline can be heated more quickly by the heating module.

[0100] In a possible implementation, the waste heat recovery module 107 is specifically configured to calculate the waste heat utilization rate using the following expression:

[0101]

[0102] Q recover =m media ·C media ·(T ortmedia -T inmedia );

[0103] Q in =m oil ·C oil ·(T in -T out );

[0104] Among them, η represents the waste heat utilization rate, Q recover Indicates the recovered heat, Q in Indicates the heat of the thermal oil before heat recovery, m media represents the mass flow rate of heat medium in the waste heat recovery module, C media Indicates the specific heat capacity of the heat medium in the waste heat recovery module, T outmedia Indicates the heat medium outlet temperature, T inmedia Indicates the heat medium inlet temperature, m oilrepresents the mass flow rate of thermal oil at the inlet of the waste heat recovery module, C oil Indicates the specific heat capacity of the heat transfer oil at the inlet of the waste heat recovery module, T in Indicates the oil temperature at the heat exchanger inlet of the waste heat recovery module, T out Indicates the oil temperature at the outlet of the heat exchanger in the waste heat recovery module.

[0105] In one example, the heat calculation unit in the waste heat recovery module 107 calculates the waste heat utilization rate using the above expression. In the embodiment of the present invention, the waste heat utilization rate η is defined as the percentage of the actual recovered heat to the total recoverable heat. The total recoverable heat is the heat Q of the heat transfer oil before heat recovery. in , which represents the heat of the heat transfer oil flowing into the waste heat recovery module from each heat transfer oil pipeline. Since the heat recovery is performed by the heat exchanger in the waste heat recovery module (the plate heat exchanger mentioned above), the oil temperature at the inlet and outlet of the heat exchanger is used to calculate the total recoverable heat. The mass flow rate and specific heat capacity of the heat transfer oil at the inlet of the waste heat recovery module are measured by the heat transfer oil flow meter placed at the inlet of the waste heat recovery module to calculate the heat Q of the heat transfer oil before heat recovery. in The actual recovered heat is Q recover , which represents the heat exchanged between the heat transfer oil flowing into the waste heat recovery module through each heat transfer oil pipeline and the refrigerant in the waste heat recovery module. During this process, the refrigerant in the waste heat recovery module is converted into heat medium. Accordingly, the actual recovered heat is also the heat of the heat medium in the waste heat recovery module. The actual recovered heat is calculated using the mass flow rate, specific heat capacity, and inlet and outlet temperatures of the heat medium in the waste heat recovery module.

[0106] In an ideal situation, if there is no heat loss in the heat exchanger, η approaches the theoretical maximum value. However, in actual use, the heat exchange efficiency must be considered. For example, the heat exchange efficiency of a plate heat exchanger is about 85-90%. Corrected to: Wherein, δ represents the heat transfer efficiency of the heat exchanger.

[0107] In an embodiment of the present invention, the waste heat recovery module recovers the heat of the thermal oil flowing out of each thermal oil pipeline, so as to give priority to preheating new thermal oil or providing external heat. At the same time, the waste heat utilization rate is calculated so that the waste heat and the main heating of the heating module can be coordinated to control the process of heating the thermal oil, which can improve the waste heat utilization rate while saving energy comprehensively.

[0108] In a possible embodiment, the thermal oil heating and temperature control system 100 further includes a vibration viscometer, which is deployed in the thermal oil storage tank 108;

[0109] A vibration viscometer, used to measure the damping decay time of the vibrator in the heat transfer oil and send the damping decay time to the temperature control module 102;

[0110] The temperature control module 102 is further configured to receive the damping decay time and calculate the viscosity of the thermal oil in the thermal oil storage tank based on the damping decay time.

[0111] Thermal oil will oxidize, crack, and carbonize during long-term high-temperature operation. These oxidation and cracking reactions affect its viscosity. Oxidation produces macromolecular polymers, which increase the oil's viscosity (e.g., from 40 cSt to 60 cSt). High-temperature cracking breaks long-chain hydrocarbons into short-chain molecules, which decreases the oil's viscosity (e.g., from 40 cSt to 30 cSt).

[0112] In an embodiment of the present invention, a vibrating viscometer deployed in a thermal oil storage tank is used to calculate the viscosity of the thermal oil by measuring the damping decay time of the vibrator in the thermal oil. Specifically, the viscosity of the thermal oil can be calculated periodically, such as once every 10 minutes, once an hour, or once a day. In one example, the viscosity of the thermal oil in the thermal oil storage tank can be calculated using the following expression:

[0113] μ=k·ρ·τ;

[0114] Wherein, μ represents the viscosity of the thermal oil, k represents the calibration coefficient, ρ represents the density of the thermal oil, and τ represents the damping decay time. For example, the calibration coefficient k can be determined by single-point calibration or multi-point calibration. Specifically, the single-point calibration method can be, for example, using a standard liquid with known viscosity, and the density and damping decay time of the standard liquid are known, and then the expression The calibration coefficient k is calculated. Correspondingly, a multi-point calibration method uses multiple sets of standard solutions with known viscosities. Each standard solution has a known density and damping decay time. The slope k, which is the calibration coefficient, is obtained by curve fitting the data using the expression μ = k·(ρ·τ).

[0115] When the viscosity of the heat transfer oil is calculated, the expression Calculate the viscosity change rate of the thermal oil Δμ%, where μ current Indicates the current viscosity of the thermal oil, μ new Indicates the initial viscosity of the thermal oil (i.e., the viscosity of the new thermal oil). The viscosity change rate is used to determine whether the thermal oil needs to be replaced. For example, if |Δμ%|>20%, an alarm message is issued to prompt the replacement of the thermal oil.

[0116] By calculating the viscosity of thermal oil, you can monitor its quality online and assess its aging. Because increasing viscosity decreases its heat transfer coefficient, calculating the viscosity of the thermal oil allows you to dynamically adjust the heating power of the heating modules corresponding to each thermal oil pipeline, improving temperature control accuracy.

[0117] In one possible implementation, the temperature control module 102 is specifically configured to calculate, for each heating module corresponding to each thermal oil pipeline, the adjusted heating temperature to be adjusted in the next time period based on the waste heat utilization rate, the viscosity of the thermal oil, the target temperature of the thermal oil pipeline, and the heating temperature of the thermal oil in the thermal oil pipeline in the current time period, using the following expression:

[0118]

[0119] e(t)=T set -T actual ;

[0120] Where u(t) represents the heating temperature to be adjusted in the next time period of the heating module corresponding to the thermal oil pipeline, K p Represents the proportionality coefficient, K i Indicates the integral coefficient, K f represents the differential coefficient, e(t) represents the deviation between the target temperature of the heat transfer oil pipeline and the heating temperature of the heat transfer oil in the heat transfer oil pipeline during the current time period, T set Indicates the target temperature of the thermal oil pipeline, T actual represents the heating temperature of the heat transfer oil in the heat transfer oil pipeline during the current time period, α represents the oil quality attenuation weight, Δμ represents the viscosity change of the heat transfer oil, f(Δμ) represents the viscosity change compensation function, β represents the waste heat recovery weight, and η represents the waste heat utilization rate;

[0121] According to the heating temperature to be adjusted, the corresponding heating power to be adjusted is determined.

[0122] For example, f(Δμ) can be a linear or piecewise function, f(Δμ)=Δμ / μ new The oil quality attenuation weight α can be expressed as α>1 means that the aging of the thermal oil has led to an increase in viscosity, and the heating power needs to be increased to compensate for the decrease in the heat transfer efficiency of the thermal oil; α<1 means that the cracking of the thermal oil has led to a decrease in viscosity, and the heating power needs to be reduced to prevent overheating. The waste heat recovery weight β is used to quantify the impact of waste heat recovery on the main heating power (that is, the heating power of the heating module corresponding to each thermal oil pipeline). The larger the β value, the stronger the compensation of the main heating power by waste heat recovery, the more dependent the thermal oil heating and temperature control system is on waste heat, and the main heating power is reduced; the smaller the β value, the lower the waste heat contribution weight, the main heating needs to bear more load, and the main heating power is increased. In actual applications, the waste heat recovery weight β can be set in combination with the energy efficiency goals, waste heat utilization priority, and real-time operating conditions of the thermal oil heating and temperature control system. For example, the basic value of β can be set to 0.2-0.4. In actual application, the basic value is determined according to the priority of waste heat utilization, and the β value is dynamically optimized based on parameters such as the real-time waste heat utilization rate η, the ambient temperature of the heat-using equipment, and the oil quality status. During the optimization process, considering safety, it is necessary to ensure that the main heating power is not lower than the minimum heating requirement. The waste heat recovery weight β can also be determined through experimental calibration, training prediction models, and using rules.

[0123] In the embodiment of the present invention, the temperature control module 102 uses an improved fuzzy PID algorithm to calculate the heating power of the heating module corresponding to each thermal oil pipeline. In one example, the PID parameter K can be calibrated experimentally during the initialization phase. p , K i and K d Set the initial value K p0 , K i0 and K d0 , in the actual heating process, dynamically adjust K p , K i and K d For example, K can be adjusted according to a preset step size. p , K i and K b For example, K p , K i and K d Adjustment can be performed using a fixed step size or an adaptive step size. The fixed step size can be set according to actual needs, such as 0.1, 0.01, etc. The adaptive step size can be set based on the rate of change of the deviation e(t) to ΔK = 0.1·|de(t) / dt|, etc.

[0124] The above process of calculating the heating temperature to be adjusted in the next time period can be based on the heat balance equation Q 加热 =Q 需求 -Q in·η is designed, that is, the heat required by the heat-using equipment (or heat transfer oil pipeline) is the difference between the required heat and the heat recovered from the waste heat (that is, the product of the heat of the heat transfer oil before heat recovery and the waste heat utilization rate). For example, when Q in (ie waste heat) increases, Q can be reduced 加热 When recovering waste heat, the heat medium flow rate can be adjusted by controlling the opening and closing degree of the temperature control valve of the waste heat recovery module 107 to ensure stable output of waste heat.

[0125] When the heating temperature to be adjusted is obtained by calculation, the heating power to be adjusted corresponding to the heating temperature to be adjusted may be determined according to a preset temperature-power correspondence table.

[0126] In the embodiment of the present invention, the temperature control module dynamically calculates the heating power to be adjusted for the next time period of the heating module corresponding to each thermal oil pipeline in real time or periodically, so as to dynamically adjust the power of the heating module corresponding to each thermal oil pipeline, thereby improving the accuracy of thermal oil heating temperature control and shortening the heating time of each thermal oil pipeline. Dynamic power allocation can reduce ineffective heating and reduce energy consumption. In addition, for K p , K i and K d Dynamic adjustment can reduce the workload of manual parameter adjustment and enhance the robustness of the temperature control module. Experiments have shown that by dynamically adjusting the power of the heating modules corresponding to each thermal oil pipeline based on waste heat utilization and thermal oil viscosity, temperature control accuracy can be improved to ±0.5°C, with regional temperature differences less than or equal to 2°C.

[0127] In one possible embodiment, the temperature control module 102 may further use the following expression to calculate the heating power to be adjusted for the next time period for the heating module corresponding to each thermal oil pipeline directly based on the target temperature of the thermal oil pipeline and the heating temperature of the thermal oil in the thermal oil pipeline during the current time period:

[0128]

[0129] Among them, P j represents the heating power to be adjusted of the heating module corresponding to the jth thermal oil pipeline, P current Indicates the current heating power of the heating module corresponding to the jth thermal oil pipeline, K p Represents the proportionality coefficient, K i Indicates the integral coefficient, K d represents the differential coefficient, e j (t) represents the deviation between the target temperature of the jth thermal oil pipeline and the heating temperature of the thermal oil in the thermal oil pipeline during the current time period, γ represents the thermal diffusion compensation coefficient set to a value between 0.1 and 0.3, ΔT = T j+1 -T jis the heating temperature T of the thermal oil in the j+1th thermal oil pipeline j+1 The heating temperature T of the heat transfer oil in the jth heat transfer oil pipeline j temperature difference.

[0130] Alternatively, the adjusted heating power required to be adjusted for the next time period calculated in this way is modified, and the correction method can be, for example, the average value or weighted average value of the two, etc., to further improve the temperature control accuracy of the thermal oil heating.

[0131] In a possible embodiment, the thermal oil heating and temperature control system 100 further includes a third detection module, which is deployed in the thermal oil storage tank 108;

[0132] The third detection module is used to measure the capacitance of the thermal oil in the thermal oil storage tank 108 and send the capacitance to the temperature control module 102;

[0133] The temperature control module 102 is further configured to receive capacitance, calculate the dielectric constant of the thermal oil in the thermal oil storage tank 108 based on the capacitance, and calculate the aging degree of the thermal oil according to the viscosity and dielectric constant of the thermal oil in the thermal oil storage tank 108 .

[0134] Exemplarily, the third detection module may be a capacitive sensor.

[0135] Thermal oil will oxidize, crack, and carbonize during long-term high-temperature operation, generating polar substances (such as carboxylic acids, ketones, and colloids). These polar substances will significantly increase the dielectric constant of the thermal oil. For example, the dielectric constant of fresh mineral oil is about 2.2 to 2.5, but it may rise to over 3.0 after aging.

[0136] In an embodiment of the present invention, a capacitive sensor (third detection module) is used to calculate the dielectric constant of the thermal oil in the thermal oil storage tank 108 by measuring the change in capacitance between electrodes. Specifically, the dielectric constant of the thermal oil can be calculated periodically, such as once every 10 minutes, once an hour, or once a day. In one example, the dielectric constant of the thermal oil in the thermal oil storage tank 108 can be calculated using the following expression:

[0137]

[0138] Where, ε represents the dielectric constant of the thermal oil, c oil Indicates the capacitance of the thermal oil, c vacuum Indicates vacuum permittivity. The capacitance value of thermal oil is proportional to the dielectric constant and directly reflects the content of polar substances in the thermal oil.

[0139] When the dielectric constant of the thermal oil is calculated, the expression Calculate the dielectric constant change rate of the thermal oil Δε%, where ε current Indicates the current dielectric constant of the thermal oil, ε new Indicates the initial dielectric constant of the thermal oil (i.e., the dielectric constant of new thermal oil). In an example, when Δε% > 5%, the thermal oil is considered to have entered the moderate aging stage; when Δε% > 10%, the thermal oil is considered to have severely aged and needs to be replaced.

[0140] By calculating the dielectric constant of the heat transfer oil, online monitoring of the heat transfer oil quality can be achieved, so as to evaluate the aging degree of the heat transfer oil.

[0141] Once the viscosity and dielectric constant of the thermal oil have been calculated, changes in these values ​​can be used to identify the reactions occurring within the oil, allowing for timely response. For example, if both viscosity and dielectric constant increase, oxidation is the primary cause of the reaction, requiring antioxidant treatment. If viscosity decreases but dielectric constant increases, cracking is the primary cause of the reaction, requiring filtration or replacement.

[0142] After calculating the viscosity and dielectric constant of the thermal oil, the aging degree F of the thermal oil can be calculated using the expression F = ω1εΔε% + ω2·|Δμ%|. The weights ω1 and ω2 can be set based on actual needs, for example, ω1 = 0.6 and ω2 = 0.4. For example, when the calculated F is greater than a first value, an alarm can be issued to indicate that the thermal oil is aging or needs to be replaced. When the calculated F is greater than a second value, a mandatory maintenance procedure can be initiated, indicating the need for urgent replacement of the thermal oil or cessation of heating. The first and second values ​​can be set based on actual needs, for example, 7 and 10, respectively.

[0143] Calculate the aging degree of the heat transfer oil to achieve online monitoring of the heat transfer oil quality, so that timely countermeasures can be taken when the heat transfer oil ages seriously.

[0144] In one possible implementation, Figure 2 As shown, the thermal oil heating temperature control system 100 further includes a remote monitoring platform 109, which is connected to the temperature control module 102;

[0145] The remote monitoring platform 109 is used to send device heating instructions and data transmission instructions to the temperature control module 102, and receive and display the data uploaded by the temperature control module 102;

[0146] The temperature control module 102 is further configured to upload the heating temperature of each heat transfer oil pipeline, the heating power of the corresponding heating module, and the aging degree of the heat transfer oil to the remote monitoring platform 109 upon receiving a data transmission instruction.

[0147] Remote monitoring platform 109 can be a client or server device, acting as a master controller. Users can remotely control temperature control module 102 through remote monitoring platform 109 to dynamically adjust the power of heating modules 105 corresponding to each thermal oil pipeline 104 to heat the heat-consuming device. In one example, a user can send a device heating instruction to temperature control module 102 through remote monitoring platform 109. Upon receiving the device heating instruction, temperature control module 102 sends an ambient temperature detection instruction to first detection module 101, causing first detection module 101 to monitor the temperature of the environment surrounding the heat-consuming device. When starting the equipment heating, the user can send a data transmission instruction to the temperature control module 102 through the remote monitoring platform 109. The data transmission instruction may include the identification of the data to be transmitted (for example, the data identification of the heating temperature of the thermal oil pipeline 104 and the data identification of the heating power of the corresponding heating module 105, as well as the data identification of the thermal oil aging degree value), the time period for transmitting the data, etc. When the temperature control module 102 receives the data transmission instruction, it uploads the heating temperature of each thermal oil pipeline 104 and the heating power of the corresponding heating module 105, as well as the thermal oil aging degree value to the remote monitoring platform 109. The remote monitoring platform 109 receives and displays the data uploaded by the temperature control module 102.

[0148] In the embodiment of the present invention, the temperature control module can be remotely controlled by the remote monitoring platform to dynamically adjust the power of the heating modules corresponding to each thermal oil pipeline to heat the heat-consuming equipment, thereby reducing manual intervention and being more suitable for unmanned environments.

[0149] For example, for a heating and temperature control scenario where the heat-using equipment is a gas pipeline, the gas pipeline is a DN300 pipeline with a length of 5km. The main circulation pump flow rate is 200L / min, the main circulation pump head is 60m, the auxiliary circulation pump flow rate is 40L / min, and the auxiliary circulation pump head is 20m. The first detection module and the second detection module both use PT100 thermal resistors. The thermal oil pipeline is segmented corresponding to the gas pipeline, with each segment being divided into 50m sections. Each section is equipped with a corresponding heating module and a second detection module, and the waste heat recovery module is connected to the heating system (the water temperature requirement is 50-60°C). The operating effect of the thermal oil heating and temperature control system provided by the embodiment of the present invention is: the temperature difference is ±0.5°C, the waste heat utilization rate is 65%, and the energy saving rate is increased by 35% compared with the traditional heating method.

[0150] For example, in a heating and temperature control scenario involving a chemical reactor with a 10-cubic-meter volume and three heating zones: upper, middle, and lower. The main circulation pump uses an explosion-proof magnetic pump with a flow rate of 150 L / min, and the dielectric constant sensor used for oil quality monitoring has an accuracy of ±2%. Using the thermal oil heating and temperature control system provided by an embodiment of the present invention, the operating results are: a temperature control differential of ±0.3°C (during the reaction), an extension of the maintenance cycle from three months to six months, and a 70% reduction in the failure rate.

[0151] The embodiment of the present invention also provides a method for controlling the temperature of thermal oil heating. Figure 3 As shown, the method is applied to the above-mentioned thermal oil heating and temperature control system, and includes:

[0152] S301, the first detection module sends the detected ambient temperature of the heat-using device to the temperature control module;

[0153] S302: The temperature control module sends a drive instruction including a rotational speed to the circulating pump; calculates the initial heating power corresponding to each thermal oil pipeline and includes it in a heating instruction and sends it to the corresponding heating module; and sends an oil temperature detection instruction to each second detection module;

[0154] S303, a circulation pump drives the thermal oil to each thermal oil pipeline;

[0155] S304, the heating module heats the heat-consuming device according to the corresponding initial heating power;

[0156] S305, the second detection module sends the heating temperature of the corresponding thermal oil pipeline in the current time period to the temperature control module;

[0157] S306, the waste heat recovery module recovers heat from the thermal oil flowing out of each thermal oil pipeline, calculates the waste heat utilization rate and sends it to the temperature control module;

[0158] S307, the temperature control module calculates the required heating power to be adjusted for the next time period based on the waste heat utilization rate, the target temperature of each heat transfer oil pipeline and the heating temperature in the current time period, and includes it in the heating instruction and sends it to the corresponding heating module for subsequent heating and temperature control.

[0159] The present invention provides a method for heating and controlling thermal oil temperature. This method utilizes multiple, segmented thermal oil pipelines to heat heat-consuming equipment, further improving heating uniformity for the equipment. Each thermal oil pipeline is individually temperature-controlled. During the heating process, the heating power of the heating modules corresponding to each pipeline is dynamically adjusted based on the residual heat utilization rate of the thermal oil, improving the accuracy of thermal oil heating and temperature control. Furthermore, the dynamic allocation of heating power to the heating modules corresponding to each pipeline during the heating process reduces ineffective heating and, therefore, reduces overall energy consumption.

[0160] In a possible implementation, the method further includes: upon receiving the device heating instruction, the temperature control module sends an ambient temperature detection instruction to the first detection module;

[0161] The temperature control module calculates the initial heating power corresponding to each thermal oil pipeline and includes it in a heating instruction and sends it to the corresponding heating module, including: in response to receiving the ambient temperature sent by the first detection module, the temperature control module calculates the initial heating power of the heating module corresponding to each thermal oil pipeline based on the ambient temperature and the target temperature of each thermal oil pipeline, and sends the heating instruction including the initial heating power to the corresponding heating module;

[0162] The heating module heats the heat-consuming equipment according to the corresponding initial heating power, including: the heating module receives the heating instruction including the initial heating power, and heats the heat-conducting oil in the heat-conducting oil pipeline connected to it according to the initial heating power to heat the heat-consuming equipment outside the corresponding heat-conducting oil pipeline.

[0163] In one possible implementation, the temperature control module calculates the initial heating power of the heating module corresponding to each thermal oil pipeline based on the ambient temperature and the target temperature of each thermal oil pipeline, including:

[0164] The following expression is used to calculate the initial heating power corresponding to the thermal oil pipeline based on the ambient temperature and the target temperature of the thermal oil pipeline:

[0165]

[0166] Among them, P base represents the initial heating power corresponding to the heat transfer oil pipeline, λ represents the thermal conductivity of the heat transfer oil pipeline insulation layer, T set Indicates the target temperature of the thermal oil pipeline, T env Indicates the ambient temperature, D ins Indicates the outer diameter of the thermal oil pipeline insulation layer, D pipe Indicates the outer diameter of the heat-using equipment, L segment Indicates the length of the thermal oil pipeline corresponding to the heating equipment.

[0167] In a possible implementation, the waste heat recovery module calculates the waste heat utilization rate, including:

[0168] The waste heat utilization rate is calculated using the following expression:

[0169]

[0170] Q recover =m media ·C media ·(Toutmedia -T inmedia );

[0171] Q in =m oil ·C oil ·(T in -T out );

[0172] Among them, η represents the waste heat utilization rate, Q recover Indicates the recovered heat, Q in Indicates the heat of the thermal oil before heat recovery, m media represents the mass flow rate of heat medium in the waste heat recovery module, C media Indicates the specific heat capacity of the heat medium in the waste heat recovery module, T outmedia Indicates the heat medium outlet temperature, T inmedia Indicates the heat medium inlet temperature, m oil represents the mass flow rate of thermal oil at the inlet of the waste heat recovery module, C oil Indicates the specific heat capacity of the heat transfer oil at the inlet of the waste heat recovery module, T in Indicates the oil temperature at the heat exchanger inlet of the waste heat recovery module, T out Indicates the oil temperature at the outlet of the heat exchanger in the waste heat recovery module.

[0173] In one possible implementation, the temperature control module calculates the required heating power to be adjusted for the next time period based on the waste heat utilization rate, the target temperature of each thermal oil pipeline, and the heating temperature in the current time period, including:

[0174] The following expression is used to calculate the required heating temperature for the next time period for each heating module corresponding to each thermal oil pipeline based on the waste heat utilization rate, the viscosity of the thermal oil, the target temperature of the thermal oil pipeline, and the heating temperature of the thermal oil in the thermal oil pipeline during the current time period:

[0175]

[0176] e(t)=T set -T actual ;

[0177] Where u(t) represents the heating temperature to be adjusted in the next time period of the heating module corresponding to the thermal oil pipeline, K p Represents the proportionality coefficient, K i Indicates the integral coefficient, K d represents the differential coefficient, e(t) represents the deviation between the target temperature of the heat transfer oil pipeline and the heating temperature of the heat transfer oil in the heat transfer oil pipeline during the current time period, T set Indicates the target temperature of the thermal oil pipeline, T actualrepresents the heating temperature of the heat transfer oil in the heat transfer oil pipeline during the current time period, α represents the oil quality attenuation weight, Δμ represents the viscosity change of the heat transfer oil, f(Δμ) represents the viscosity change compensation function, β represents the waste heat recovery weight, and η represents the waste heat utilization rate;

[0178] According to the heating temperature to be adjusted, the corresponding heating power to be adjusted is determined.

[0179] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0180] Each embodiment in this specification is described in a related manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0181] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included in the scope of protection of the present invention.

Claims

1. A thermal oil heating and temperature control system, characterized in that: The system includes: a first detection module, a temperature control module, a circulation pump, a waste heat recovery module, a plurality of segmented thermal oil pipelines and their corresponding heating modules, and a second detection module; A first detection module is used to send the detected ambient temperature of the heat-consuming device to the temperature control module; The temperature control module is used to send a drive instruction including a rotation speed to the circulation pump; calculate the initial heating power corresponding to each thermal oil pipeline and include it in the heating instruction and send it to the corresponding heating module; send an oil temperature detection instruction to each second detection module; Circulation pump, used to drive the thermal oil to each thermal oil pipeline; A heating module, used for heating the heat-consuming equipment according to the corresponding initial heating power; The second detection module is used to send the heating temperature of the corresponding thermal oil pipeline in the current time period to the temperature control module; The waste heat recovery module is used to recover the heat from the heat transfer oil flowing out of each heat transfer oil pipeline, calculate the waste heat utilization rate and send it to the temperature control module; The temperature control module is also used to calculate the required adjusted heating power for the next time period based on the waste heat utilization rate, the target temperature of each heat transfer oil pipeline and the heating temperature in the current time period, and include it in the heating instruction and send it to the corresponding heating module for subsequent heating and temperature control.

2. The system according to claim 1, wherein: The system also includes a thermal oil storage tank; The temperature control module is specifically configured to, upon receiving a device heating instruction, send an ambient temperature detection instruction to the first detection module and a drive instruction including a rotational speed to the circulating pump; in response to receiving the ambient temperature sent by the first detection module, calculate the initial heating power of the heating module corresponding to each thermal oil pipeline based on the ambient temperature and the target temperature of each thermal oil pipeline, and send a heating instruction including the initial heating power to the corresponding heating module; The heating module is specifically configured to receive the heating instruction including the initial heating power, and heat the thermal oil in the thermal oil pipeline connected thereto according to the initial heating power, so as to heat the heat-consuming equipment outside the corresponding thermal oil pipeline; The waste heat recovery module is also used to drive the heat-conducting oil after heat recovery to the heat-conducting oil storage tank; The thermal oil storage tank is used to provide thermal oil to each thermal oil pipeline under the drive of the circulation pump, and to recover the thermal oil passing through the waste heat recovery module.

3. The system according to claim 1 or 2, characterized in that The circulating pump is a multi-stage circulating pump, which includes a parallel main circulating pump and at least one auxiliary circulating pump.

4. The system according to claim 2, wherein: The temperature control module is specifically configured to calculate the initial heating power corresponding to the thermal oil pipeline based on the ambient temperature and the target temperature of the thermal oil pipeline using the following expression: Among them, P base represents the initial heating power corresponding to the heat transfer oil pipeline, λ represents the thermal conductivity of the heat transfer oil pipeline insulation layer, T set Indicates the target temperature of the thermal oil pipeline, T env Indicates the ambient temperature, D ins Indicates the outer diameter of the thermal oil pipeline insulation layer, D pipe Indicates the outer diameter of the heat-using equipment, L segment Indicates the length of the thermal oil pipeline corresponding to the heating equipment.

5. The system according to claim 2, wherein: The waste heat recovery module is specifically used to calculate the waste heat utilization rate using the following expression: Q recover =m media ·C media ·(T outmedia -T inmedia ); Q in =m oil ·C oil ·(T in -T out ); Among them, η represents the waste heat utilization rate, Q recover Indicates the recovered heat, Q in Indicates the heat of the thermal oil before heat recovery, m media represents the mass flow rate of heat medium in the waste heat recovery module, C media Indicates the specific heat capacity of the heat medium in the waste heat recovery module, T outmedia Indicates the heat medium outlet temperature, T inmedia Indicates the heat medium inlet temperature, m oil represents the mass flow rate of thermal oil at the inlet of the waste heat recovery module, C oil Indicates the specific heat capacity of the heat transfer oil at the inlet of the waste heat recovery module, T in Indicates the oil temperature at the heat exchanger inlet of the waste heat recovery module, T out Indicates the oil temperature at the outlet of the heat exchanger in the waste heat recovery module.

6. The system according to claim 5, characterized in that The system further comprises a vibration viscometer, which is deployed in the thermal oil storage tank; The vibration viscometer is used to measure the damping decay time of the vibrator in the thermal oil and send the damping decay time to the temperature control module; The temperature control module is further configured to receive the damping decay time and calculate the viscosity of the thermal oil in the thermal oil storage tank based on the damping decay time.

7. The system according to claim 6, characterized in that The temperature control module is specifically configured to calculate, for each heating module corresponding to each thermal oil pipeline, the heating temperature to be adjusted in the next time period based on the waste heat utilization rate, the viscosity of the thermal oil, the target temperature of the thermal oil pipeline, and the heating temperature of the thermal oil in the thermal oil pipeline in the current time period using the following expression: e(t)=T set -T actual ; Where u(t) represents the heating temperature to be adjusted in the next time period of the heating module corresponding to the thermal oil pipeline, K p Represents the proportionality coefficient, K i Indicates the integral coefficient, K d represents the differential coefficient, e(t) represents the deviation between the target temperature of the heat transfer oil pipeline and the heating temperature of the heat transfer oil in the heat transfer oil pipeline during the current time period, T set Indicates the target temperature of the thermal oil pipeline, T actual represents the heating temperature of the heat transfer oil in the heat transfer oil pipeline during the current time period, α represents the oil quality attenuation weight, Δμ represents the viscosity change of the heat transfer oil, f(Δμ) represents the viscosity change compensation function, β represents the waste heat recovery weight, and η represents the waste heat utilization rate; According to the heating temperature to be adjusted, the corresponding heating power to be adjusted is determined.

8. The system according to claim 6, wherein: The system further includes a third detection module, which is deployed in the thermal oil storage tank; The third detection module is used to measure the capacitance of the thermal oil in the thermal oil storage tank and send the capacitance to the temperature control module; The temperature control module is further used to receive the capacitor and calculate the dielectric constant of the thermal oil in the thermal oil storage tank based on the capacitor, and calculate the aging degree value of the thermal oil according to the viscosity and dielectric constant of the thermal oil in the thermal oil storage tank.

9. The system according to claim 8, characterized in that The system also includes a remote monitoring platform; The remote monitoring platform is used to send equipment heating instructions and data transmission instructions to the temperature control module, and receive and display the data uploaded by the temperature control module; The temperature control module is further configured to upload the heating temperature of each heat transfer oil pipeline, the heating power of the corresponding heating module, and the aging degree value of the heat transfer oil to the remote monitoring platform upon receiving the data transmission instruction.

10. A method for heating and controlling temperature of thermal oil, characterized in that: Applied to the thermal oil heating and temperature control system according to any one of claims 1 to 9, the method comprises: The first detection module sends the detected ambient temperature of the heat-using device to the temperature control module; The temperature control module sends a drive instruction including the speed to the circulation pump; calculates the initial heating power corresponding to each thermal oil pipeline and includes it in the heating instruction and sends it to the corresponding heating module; and sends an oil temperature detection instruction to each second detection module; The circulation pump drives the thermal oil to each thermal oil pipeline; The heating module heats the heat-consuming equipment according to the corresponding initial heating power; The second detection module sends the heating temperature of the corresponding thermal oil pipeline in the current time period to the temperature control module; The waste heat recovery module recovers the heat from the heat transfer oil flowing out of each heat transfer oil pipeline, calculates the waste heat utilization rate and sends it to the temperature control module; The temperature control module calculates the required heating power to be adjusted for the next time period based on the waste heat utilization rate, the target temperature of each heat transfer oil pipeline and the heating temperature in the current time period, and includes it in the heating instruction and sends it to the corresponding heating module for subsequent heating and temperature control.

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