Small photo-thermal utilization system and method suitable for oil field station yard

Abstract

The invention relates to a small photo-thermal utilization system and method suitable for an oil field station. The system comprises a solar heat collector, a heat storage device, a variable frequency pump, a heat exchanger, a PLC control cabinet, a low-voltage control cabinet and a variable-frequency governor. The solar heat collector is connected with the heat exchanger and the heat storage device, the variable frequency pump is connected between the heat exchanger and the heat storage device, the heat exchanger is connected with a well site produced liquid pipeline and an oil field station crude oil treatment pipeline, and the variable frequency governor is connected with the variable frequency pump. The PLC control cabinet is connected with the solar heat collector, the heat storage device, the heat exchanger and the low-pressure control cabinet. When the first temperature signal of the solar heat collector is larger than or equal to the first working temperature signal, the PLC control cabinet controls the solar heat collector to directly exchange heat for the heat exchanger, and redundant heat is stored in the heat storage device. Under cloudy and rainy weather and night conditions, the heat storage device exchanges heat with wellhead produced liquid through a high-temperature heat supply medium, and application of solar photo-thermal utilization in an oil field station yard is achieved.

Description

Technical Field

[0001] The invention relates to a small-scale light-heat utilization system and method suitable for oil field stations. Background Art

[0002] As a large-scale energy-consuming industry, oilfield enterprises are in urgent need of solving the problems of low-carbon development and green transformation. As one of the abundant clean energy sources, solar energy can be mainly used in the following ways: photothermal utilization, photoelectric conversion utilization, and photochemical conversion utilization. The temperature range required for oilfield stations is between 40℃ and 70℃. The production needs of oilfield stations can be met by directly utilizing solar energy. However, oilfield stations have not yet applied solar thermal utilization on a large scale, and a universal small-scale photothermal utilization system is still under exploration. Summary of the invention

[0003] In order to realize the application of solar thermal energy in oilfield stations and meet the production needs of oilfield stations, the present invention proposes a small solar thermal energy utilization system and method suitable for oilfield stations. The technical solution proposed by the present invention is as follows:

[0004] In a first aspect, the present invention provides a small-scale solar thermal utilization system suitable for oil field stations, comprising: a solar thermal collector, a heat storage device, a variable frequency pump, a heat exchanger, a PLC control cabinet, a low voltage control cabinet and a variable frequency speed regulator;

[0005] The solar thermal collector is connected to the heat exchanger and the heat storage device;

[0006] The heat exchanger is connected to the heat storage device, the variable frequency pump is connected between the heat exchanger and the heat storage device, and the heat exchanger is connected to the well site produced fluid pipeline and the oil field station crude oil processing pipeline;

[0007] The low-voltage control cabinet is connected to the PLC control cabinet and the variable frequency speed regulator respectively, and the variable frequency speed regulator is connected to the variable frequency pump;

[0008] The PLC control cabinet is respectively connected to the solar collector, the heat storage device, the heat exchanger and the low-voltage control cabinet, and is used to control the movement of the solar collector to change the heat collection direction; when the first temperature signal of the solar collector is greater than or equal to the first working temperature signal, the solar collector is controlled to directly exchange heat with the heat exchanger and store excess heat in the heat storage device; when the temperature signal of the heat exchanger reaches the first working temperature signal, the heat exchanger is controlled to exchange heat with oilfield produced fluid or crude oil processed by the oilfield station; and when the first temperature signal is less than the first working temperature signal, the second working temperature signal of the heat storage device is determined according to the first temperature signal; when the second temperature signal of the heat storage device reaches the second working temperature signal, the variable frequency pump is started, and the variable frequency speed regulator is controlled to adjust the frequency of the variable frequency pump according to the second working temperature signal, so that the heat medium in the pipeline connecting the variable frequency pump and the heat storage device circulates and heats up until the heat medium is heated to the first working temperature signal, and the heat exchanger is controlled to exchange heat with the oilfield produced fluid or crude oil processed by the oilfield station.

[0009] In one or some embodiments, the heat collection medium of the solar thermal collector is thermal oil, and the system further includes a thermal oil circulation pump connected between the heat storage device and the solar thermal collector.

[0010] In one or some embodiments, the variable frequency speed regulator is connected to the thermal oil circulation pump.

[0011] In one or some embodiments, the system further comprises a heat medium circulation pump, and the heat medium circulation pump is connected between the heat exchanger and the well site produced fluid pipeline or the oil field station crude oil processing pipeline.

[0012] In one or some embodiments, a first temperature transmitter is provided on the inlet and outlet pipelines of the solar thermal collector.

[0013] In one or some embodiments, a first pressure transmitter is provided on the inlet and outlet pipelines of the solar thermal collector.

[0014] In one or some embodiments, a second pressure transmitter is provided on the inlet and outlet pipelines of the variable frequency pump.

[0015] In one or some embodiments, the heat exchanger is provided with a second temperature transmitter, and the second temperature transmitter is interlocked with the variable frequency pump.

[0016] In one or some embodiments, the heat storage device is provided with a first temperature sensor, and the solar thermal collector is provided with a second temperature sensor;

[0017] The PLC control cabinet is used to control the heat storage device and the solar collector to stop working when the temperature signal collected by the first temperature sensor is lower than a first preset temperature and the temperature signal collected by the second temperature sensor is lower than a second preset temperature.

[0018] In one or some embodiments, the heat storage medium of the heat storage device is a special-shaped magnesia brick.

[0019] In one or some embodiments, the heat transfer medium of the heat exchanger is antifreeze liquid.

[0020] In a second aspect, the present invention provides a small-scale photothermal utilization method applicable to an oil field station, using the small-scale photothermal utilization system applicable to an oil field station as described in the first aspect, the method comprising:

[0021] collecting a first temperature signal of a solar thermal collector in real time;

[0022] When the first temperature signal is greater than or equal to the first operating temperature signal, the solar collector is controlled to exchange heat with the heat exchanger and the excess heat is stored in the heat storage device; and when the temperature signal of the heat exchanger reaches the first operating temperature signal, the heat exchanger is controlled to exchange heat with oilfield produced fluid or crude oil processed by the oilfield station;

[0023] When the first temperature signal is less than the first working temperature signal, the second working temperature signal of the heat storage device is determined according to the first temperature signal. When the second temperature signal of the heat storage device reaches the second working temperature signal, the variable frequency pump is started, and the frequency of the variable frequency pump is adjusted by the variable frequency speed regulator according to the second working temperature signal, so that the heat medium in the pipeline connecting the variable frequency pump and the heat storage device circulates and heats up until the heat medium is heated to the first working temperature signal, and the heat exchanger is controlled to exchange heat with the oilfield produced fluid or the crude oil processed by the oilfield station.

[0024] Based on the above technical solution, the beneficial effects of the present invention compared with the prior art are as follows:

[0025] The small-scale solar thermal utilization system suitable for oil field stations provided by the present invention has a solar collector connected to a heat exchanger and a heat storage device, a heat storage device connected to a heat exchanger, a variable frequency pump connected between the heat exchanger and the heat storage device, and a heat exchanger pipeline connected to the well field produced fluid and the oil field station processed crude oil. The low-voltage control cabinet is respectively connected to the PLC control cabinet and the variable frequency speed regulator, and the variable frequency speed regulator is connected to the variable frequency pump; the PLC control cabinet is respectively connected to the solar collector, the heat storage device, the heat exchanger and the low-voltage control cabinet. The PLC control cabinet controls the solar collector to change the heat collection direction according to the movement of the sun, so that the solar energy always shines vertically on the collector until night. When solar energy is sufficient, that is, when the first temperature signal of the solar collector is greater than or equal to the first operating temperature signal, the solar collector heats the heat collecting medium, and the PLC control cabinet controls the solar collector to directly exchange heat with the heat exchanger, and stores the excess heat in the heat storage device. A part of the heat collecting medium, that is, the heat exchange part, directly exchanges heat with the oilfield produced fluid through the heat exchanger to meet the daytime production needs, and the other part, that is, the excess heat, is stored in the heat storage device. The part stored in the heat storage device ensures the normal operation of the oilfield station at night and in rainy weather. In rainy weather and at night, the heat storage device exchanges heat with the wellhead produced fluid through the high-temperature heating medium, realizing the application of solar thermal energy in the oilfield station to meet the production needs of the oilfield station. Utilize green natural resources-sunlight, maximize the use or storage of heat energy directly converted from light and heat, and replace the combustion and heating of the heating furnace in the oilfield station. It has the characteristics of energy saving and consumption reduction, reducing carbon emissions and providing stable and continuous energy, while reducing the floor space. The present invention can realize direct utilization of light and heat without secondary conversion. When the sunlight is sufficient, light and heat are directly utilized and the excess heat is stored in a heat storage device. By setting a heat storage device, when the first temperature signal is less than the first working temperature signal, that is, the energy collected by the solar collector does not meet the working requirements of the heat exchanger, the second working temperature signal of the heat storage device is determined by the PLC control cabinet according to the first temperature signal. When the second temperature signal of the heat storage device reaches the second working temperature signal, the frequency conversion pump is started, and the frequency of the frequency conversion pump is adjusted by the frequency conversion speed regulator according to the second working temperature signal. The heat transfer medium of the heat exchanger is heated by the heat storage device, so that the heat exchanger can work continuously. While utilizing light and heat, the intermittent and instability problems of light and heat are solved, the light and heat resources of the oil field are fully utilized, energy saving and consumption reduction are achieved, carbon emissions are reduced, and stable and continuous energy is provided.

[0026] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a structural schematic diagram of a small-scale solar thermal utilization system suitable for oil field stations provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0031] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0032] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] The inventor found in his work that solar thermal utilization has not been widely applied in oil field stations, and a universal small-scale solar thermal utilization system is still under exploration. The patent application with patent number CN207751040U discloses a distributed solar thermal utilization system, including: a solar thermal collection system, a power generation system, a heat pump heating system and a buried pipe heat storage system. The solar thermal collection system includes a solar collector, and the solar collector pipeline is connected to a heat transfer oil circulation pump; the power generation system includes a power generation evaporator, a working fluid pump, a power generation condenser, a screw expander and a generator, the heat pump heating system includes a heating circulation pump, a heat source circulation pump, a screw compressor, a heat pump evaporator and a heat pump condenser, and the buried pipe heat storage system includes a U-shaped buried pipe with a U-shaped end buried underground. The basic utility model based on distributed solar thermal utilization system completely replaces the utilization of primary energy such as coal and gas to meet the various needs of heating users, thereby reducing environmental pollution and harmful gas emissions. This patent adopts an underground pipe heat storage system for heat storage and includes a power generation module and a heat pump heating system. The device is large in scale and is only applicable to heating systems but not to oil field stations. The patent application with patent number CN107388598A discloses a heat transfer and heat storage separation type solar thermal utilization method and system, including a solar thermal collection field, a heat storage and heat release system and a thermal energy utilization system; the solar thermal collection field includes a solar collector, a low-temperature heat transfer medium mother pipe and a high-temperature heat transfer medium mother pipe; the heat storage and heat release system and the thermal energy utilization system are connected in parallel between the low-temperature heat transfer medium mother pipe and the high-temperature heat transfer medium mother pipe; the heat storage and heat release system includes a heat storage tank body, and the heat storage tank body is divided into a top filling area, one or more middle filling areas, and a bottom filling area that are connected in sequence according to the different positions of filling the energy storage medium, and each filling area is provided with a corresponding inlet switching valve. This method adopts a dual-circuit system with separated heat transfer and heat storage, uses a heat transfer medium to circulate and absorb solar energy in the solar collector field, and exchanges heat between the energy storage medium and the heat transfer medium in the heat storage and heat release system to store or release thermal energy. This patent only describes the heat storage module, but does not reflect the heat collection system, and cannot be fully applied to the photothermal utilization of oilfield stations. In addition, the current demand for heat load in oilfield stations mainly uses gas heating furnaces and electric heaters to meet the needs of daily production, which has problems such as excessive carbon emissions and greater environmental risks. The existing photothermal utilization equipment is large in scale and high in temperature, which is not suitable for the small scale and low temperature required by oilfield stations, and cannot meet the inventor's expectations. After further research and development, the inventor made the present invention.

[0035] Embodiment 1

[0036] The embodiment of the present invention provides a small-scale light-heat utilization system suitable for oil field stations. Figure 1 As shown, it includes: solar thermal collector, heat storage device, variable frequency pump, heat exchanger, PLC control cabinet, low voltage control cabinet and variable frequency speed regulator;

[0037] The solar thermal collector is connected to the heat exchanger and the heat storage device;

[0038] The heat exchanger is connected to the heat storage device, the variable frequency pump is connected between the heat exchanger and the heat storage device, and the heat exchanger is connected to the well site produced fluid pipeline and the oil field station crude oil processing pipeline; the heat exchanger is set to make the heat transfer medium of the heat exchanger exchange heat with the well site produced fluid and the oil field station processed crude oil, so that the well site produced fluid and the oil field station processed crude oil are heated to the target temperature; for the oil pulling station, the heat storage device can transform the oil pulling tank into a heat storage tank.

[0039] The low-voltage control cabinet is respectively connected to the PLC control cabinet and the variable frequency speed regulator, and the variable frequency speed regulator is connected to the variable frequency pump; by setting the variable frequency speed regulator, the variable frequency pump can realize variable frequency operation, adjust the flow rate of the heat storage device when the temperature of the heat transfer medium is too high or too low, and ensure the heating effect of the heat exchanger; the present invention realizes the intelligence of the photothermal utilization system by setting the PLC control cabinet and the low-voltage control cabinet.

[0040] The PLC control cabinet is respectively connected to the solar collector, the heat storage device, the heat exchanger and the low-voltage control cabinet, and is used to control the movement of the solar collector to change the heat collection direction; when the first temperature signal of the solar collector is greater than or equal to the first working temperature signal, the solar collector is controlled to directly exchange heat with the heat exchanger and store excess heat in the heat storage device; when the temperature signal of the heat exchanger reaches the first working temperature signal, the heat exchanger is controlled to exchange heat with oilfield produced fluid or crude oil processed by the oilfield station; and when the first temperature signal is less than the first working temperature signal, the second working temperature signal of the heat storage device is determined according to the first temperature signal; when the second temperature signal of the heat storage device reaches the second working temperature signal, the variable frequency pump is started, and the variable frequency speed regulator is controlled to adjust the frequency of the variable frequency pump according to the second working temperature signal, so that the heat medium in the pipeline connecting the variable frequency pump and the heat storage device circulates and heats up until the heat medium is heated to the first working temperature signal, and the heat exchanger is controlled to exchange heat with the oilfield produced fluid or crude oil processed by the oilfield station. The second operating temperature signal of the heat storage device is obtained by subtracting the first temperature signal from the first operating temperature signal, and the frequency adjustment mode of the variable frequency pump is set according to the operating parameters of the variable frequency pump.

[0041] In the embodiment of the present invention, the manner in which the PLC controls the movement of the solar collector to change the heat collection direction so that the solar energy always shines vertically toward the collector can refer to the description in the prior art and is not specifically limited here.

[0042] In this embodiment, if it is rainy and the sunlight is insufficient, the heat collection temperature of the solar collector is low, in order for the heat transfer medium of the heat exchanger to reach the preset temperature, the heat storage device needs to provide more heat, and the frequency of the frequency converter is increased by the frequency converter so that the heat exchanger can reach the above-mentioned preset temperature, that is, the working temperature of the heat exchanger, more quickly, so that the heat exchanger can exchange heat with the produced fluid of the well site or the crude oil processed by the oil field station, so that the produced fluid of the well site or the crude oil processed by the oil field station is heated up to meet the production needs of the oil field station.

[0043] In this embodiment, the system further includes a 380V low-voltage power supply, and the 380V low-voltage power supply is connected to the low-voltage control cabinet for supplying power to the low-voltage control cabinet.

[0044] The present invention belongs to the technical field of new energy and renewable energy, and provides a small-scale photothermal utilization system suitable for oilfield stations. Through efficient use of solar energy, a heat collecting medium is directly heated, a part of which is used for heat exchange, and the other part is used for storage. The heat exchange part meets the production needs during the day, and the heat storage part ensures the normal operation of the oilfield station at night and in rainy weather. It mainly utilizes green natural resources-sunlight, maximizes the use or storage of heat energy directly converted from light and heat, and replaces the combustion and heating of the heating furnace in the oilfield station. Specifically, the solar collector is connected to the heat exchanger and the heat storage device, the heat storage device is connected to the heat exchanger, the frequency conversion pump is connected between the heat exchanger and the heat storage device, and the heat exchanger pipeline is connected to the well field produced liquid and the oilfield station to process crude oil. The low-voltage control cabinet is respectively connected to the PLC control cabinet and the frequency conversion speed regulator, the frequency conversion speed regulator is connected to the frequency conversion pump; the PLC control cabinet is respectively connected to the solar collector, the heat storage device, the heat exchanger and the low-voltage control cabinet. The PLC control cabinet controls the solar collector to change the heat collection direction according to the movement of the sun, so that the solar energy always shines vertically on the collector until night. When solar energy is sufficient, that is, when the first temperature signal of the solar collector is greater than or equal to the first operating temperature signal, the solar collector heats the heat collecting medium, and the PLC control cabinet controls the solar collector to directly exchange heat with the heat exchanger, and stores the excess heat in the heat storage device. A part of the heat collecting medium, that is, the heat exchange part, directly exchanges heat with the oilfield produced fluid through the heat exchanger to meet the daytime production needs, and the other part, that is, the excess heat, is stored in the heat storage device. The part stored in the heat storage device ensures the normal operation of the oilfield station at night and in rainy weather. In rainy weather and at night, the heat storage device exchanges heat with the wellhead produced fluid through the high-temperature heating medium, realizing the application of solar thermal energy in the oilfield station to meet the production needs of the oilfield station. Utilize green natural resources-sunlight, maximize the use or storage of heat energy directly converted from light and heat, and replace the combustion and heating of the heating furnace in the oilfield station. It has the characteristics of energy saving and consumption reduction, reducing carbon emissions and providing stable and continuous energy, while reducing the floor space. The present invention can realize direct utilization of light and heat without secondary conversion. When the sunlight is sufficient, light and heat are directly utilized and the excess heat is stored in a heat storage device. By setting a heat storage device, when the first temperature signal is less than the first working temperature signal, that is, the energy collected by the solar collector does not meet the working requirements of the heat exchanger, the second working temperature signal of the heat storage device is determined by the PLC control cabinet according to the first temperature signal. When the second temperature signal of the heat storage device reaches the second working temperature signal, the frequency conversion pump is started, and the frequency of the frequency conversion pump is adjusted by the frequency conversion speed regulator according to the second working temperature signal. The heat transfer medium of the heat exchanger is heated by the heat storage device, so that the heat exchanger can work continuously. While utilizing light and heat, the intermittent and instability problems of light and heat are solved, the light and heat resources of the oil field are fully utilized, energy saving and consumption reduction are achieved, carbon emissions are reduced, and stable and continuous energy is provided.

[0045] In one embodiment, the heat collection medium of the solar thermal collector is thermal oil, and the system further includes a thermal oil circulation pump, which is connected between the heat storage device and the solar thermal collector. A thermal oil circulation pump is provided to realize the circulation of the thermal oil and maintain the heat storage effect of the heat storage device. The high-temperature thermal oil in the solar thermal collector enters the heat storage device for heat storage, the temperature of the thermal oil decreases, and the low-temperature thermal oil returns to the solar thermal collector through the thermal oil circulation pump for heat collection. When the heat storage device reaches the second working temperature signal, the frequency conversion pump is started, and the heat medium in the water pipeline connected to the frequency conversion pump and the heat storage device begins to circulate and heat up. When the heat medium is heated to the first working temperature signal, the heat exchanger starts to work; when it is rainy and the heat collection temperature of the solar thermal collector is low, the heat storage device is enabled to heat up the heat transfer medium to exchange heat for the heat exchanger.

[0046] In one embodiment, the variable frequency speed regulator is connected to the thermal oil circulation pump. The variable frequency speed regulator enables the thermal oil circulation pump to achieve variable frequency operation, adjust the flow rate when the temperature of the heat collecting medium of the solar thermal collector is too high or too low, and ensure the heating effect of the heat storage device. For example, when the solar energy is particularly strong, the temperature of the heat collecting medium of the solar thermal collector is very high, and the frequency of the thermal oil circulation pump is increased to increase the working speed of the thermal oil circulation pump, so that the excess heat can be stored in the heat storage device.

[0047] In one embodiment, the system further comprises a heat medium circulation pump, which is connected between the heat exchanger and the well field produced fluid pipeline or the oil field station crude oil processing pipeline. By providing a heat medium circulation pump, the heat transfer medium is circulated and the heating effect of the heat exchanger is ensured.

[0048] In one embodiment, a first temperature transmitter is provided on the inlet and outlet pipes of the solar thermal collector. The first temperature transmitter detects the temperature on the inlet and outlet pipes of the solar thermal collector. When the temperature on the inlet and outlet pipes is too high or continuously low, it indicates that the solar thermal collector is faulty, which is convenient for maintenance. In addition, the first temperature transmitter is interlocked with the heat storage device. When the temperature of the heat storage device is low, the frequency of the heat transfer oil circulation pump is adjusted according to the difference between the temperature signal collected by the first temperature transmitter and the temperature signal of the heat storage device. By increasing the frequency of the heat transfer oil circulation pump, the heat storage device can reach the temperature involved.

[0049] In one embodiment, the inlet and outlet pipes of the solar collector are provided with a first pressure transmitter, which is used to collect pressure signals on the inlet and outlet pipes of the solar collector. When the solar collector is in a continuous low pressure, it indicates that the solar collector has a fault, which is convenient for maintenance.

[0050] In one embodiment, a second pressure transmitter is provided on the inlet and outlet pipelines of the variable frequency pump. The second pressure transmitter is used to collect pressure signals on the inlet and outlet pipelines of the variable frequency pump. When the pressure is too high, the PLC controls the variable frequency pump to stop working, realizing the pump stopping due to pressure holding accident.

[0051] In one embodiment, the heat exchanger is provided with a second temperature transmitter, and the second temperature transmitter is interlocked with the variable frequency pump. The second temperature transmitter is used to detect the temperature of the inlet and outlet pipes of the heat exchanger, and adjust the frequency of the variable frequency pump according to the difference between the temperature signal of the well field produced fluid or the crude oil processed by the oil field station and the temperature signal collected by the second temperature transmitter, so as to meet the heat exchange demand of the well field produced fluid or the crude oil processed by the oil field station. When the temperature of the well field produced fluid or the crude oil processed by the oil field station is low, the required heat exchange energy is large, and the frequency of the variable frequency pump is adjusted according to the difference between the temperature signal of the second temperature transmitter and the temperature signal of the well field produced fluid or the crude oil processed by the oil field station, so that the well field produced fluid or the crude oil processed by the oil field station is quickly heated by increasing the frequency of the variable frequency pump, so as to ensure the stable operation of the heat exchanger under different temperatures of the heat transfer medium.

[0052] In one embodiment, the heat storage device is provided with a first temperature sensor, and the solar thermal collector is provided with a second temperature sensor;

[0053] The PLC control cabinet is used to control the heat storage device and the solar collector to stop working when the temperature signal collected by the first temperature sensor is lower than the first preset temperature, and the temperature signal collected by the second temperature sensor is lower than the second preset temperature. When the rainy weather persists, the temperature of the solar collector is lower than the second preset temperature, and the heat storage temperature of the heat storage device is lower than the first preset temperature, the solar thermal utilization system is disabled, and other complementary energy sources are used to ensure normal production and operation. By setting a low temperature alarm, the heat storage device and the solar collector are interlocked with each other. When the low temperature alarm is triggered at the same time, the solar thermal collection system is disabled, and complementary energy is used to ensure stable production.

[0054] In one embodiment, the heat storage medium of the heat storage device is a special-shaped magnesia brick. The special-shaped magnesia brick has a smaller volume, a larger heat melting point, and a faster heat transfer, which can improve the heat storage efficiency of the heat storage device.

[0055] In one embodiment, the heat transfer medium of the heat exchanger is antifreeze liquid, which may be water.

[0056] Embodiment 2

[0057] The embodiment of the present invention provides a small-scale photothermal utilization method applicable to an oil field station, using the small-scale photothermal utilization system applicable to an oil field station as described in the first embodiment, the method comprising:

[0058] collecting a first temperature signal of a solar thermal collector in real time;

[0059] When the first temperature signal is greater than or equal to the first operating temperature signal, the solar collector is controlled to exchange heat with the heat exchanger and the excess heat is stored in the heat storage device; and when the temperature signal of the heat exchanger reaches the first operating temperature signal, the heat exchanger is controlled to exchange heat with oilfield produced fluid or crude oil processed by the oilfield station;

[0060] When the first temperature signal is less than the first working temperature signal, the second working temperature signal of the heat storage device is determined according to the first temperature signal. When the second temperature signal of the heat storage device reaches the second working temperature signal, the variable frequency pump is started, and the frequency of the variable frequency pump is adjusted by the variable frequency speed regulator according to the second working temperature signal, so that the heat medium in the pipeline connecting the variable frequency pump and the heat storage device circulates and heats up until the heat medium is heated to the first working temperature signal, and the heat exchanger is controlled to exchange heat with the oilfield produced fluid or the crude oil processed by the oilfield station.

[0061] In the embodiment of the present invention, the small-scale photothermal utilization method applicable to oilfield stations corresponds to the small-scale photothermal utilization system applicable to oilfield stations described in the above-mentioned embodiment 1. Its specific implementation process can refer to the process of photothermal utilization using the small-scale photothermal utilization system applicable to oilfield stations in the above-mentioned embodiment 1. The repeated parts will not be repeated here.

[0062] 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 any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. The orientation or position relationship indicated by the terms "upper", "lower", etc. is based on the orientation or position relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0063] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict. The present invention is not limited to any single aspect, any single embodiment, or any combination and / or permutation of these aspects and / or embodiments. Each aspect and / or embodiment of the present invention can be used alone, or in combination with one or more other aspects and / or other embodiments.

[0064] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A small-scale solar thermal utilization system suitable for oil field stations, characterized in that: include: Solar collector, heat storage device, variable frequency pump, heat exchanger, PLC control cabinet, low voltage control cabinet and variable frequency speed regulator; The solar thermal collector is connected to the heat exchanger and the heat storage device; The heat exchanger is connected to the heat storage device, the variable frequency pump is connected between the heat exchanger and the heat storage device, and the heat exchanger is connected to the well site produced fluid pipeline and the oil field station crude oil processing pipeline; The low-voltage control cabinet is connected to the PLC control cabinet and the variable frequency speed regulator respectively, and the variable frequency speed regulator is connected to the variable frequency pump; The PLC control cabinet is respectively connected to the solar thermal collector, the heat storage device, the heat exchanger and the low-voltage control cabinet, and is used to control the movement of the solar thermal collector to change the heat collection direction; determine the first working temperature signal of the heat exchanger according to the temperature signal of the well field produced fluid or the crude oil processed by the oil field station; when the first temperature signal of the solar thermal collector is greater than or equal to the first working temperature signal, control the solar thermal collector to directly exchange heat with the heat exchanger and store the excess heat in the heat storage device; when the temperature signal of the heat exchanger reaches the first working temperature signal, control the heat exchanger to exchange heat with the oil field produced fluid or the crude oil processed by the oil field station; Furthermore, when the first temperature signal is less than the first working temperature signal, the second working temperature signal of the heat storage device is determined according to the first temperature signal; when the second temperature signal of the heat storage device reaches the second working temperature signal, the variable frequency pump is started, and the variable frequency speed regulator is controlled to adjust the frequency of the variable frequency pump according to the second working temperature signal, so that the heat medium in the pipeline connecting the variable frequency pump and the heat storage device circulates and heats up until the heat medium is heated to the first working temperature signal, and then the heat exchanger is controlled to exchange heat with the oilfield produced fluid or the crude oil processed by the oilfield station.

2. The small-scale light-heat utilization system suitable for oil field stations according to claim 1 is characterized in that: The heat collecting medium of the solar thermal collector is heat transfer oil. The system further comprises a heat transfer oil circulation pump connected between the heat storage device and the solar thermal collector.

3. The small-scale light-heat utilization system suitable for oil field stations according to claim 2 is characterized in that: The variable frequency speed regulator is connected to the thermal oil circulation pump.

4. The small-scale light-heat utilization system suitable for oil field stations according to claim 1 is characterized in that: The system further comprises a heat medium circulation pump, which is connected between the heat exchanger and the well site produced fluid pipeline or the oil field station crude oil processing pipeline.

5. The small-scale light-heat utilization system suitable for oil field stations according to claim 1 is characterized in that: The inlet and outlet pipelines of the solar thermal collector are provided with a first temperature transmitter.

6. The small-scale light-heat utilization system suitable for oil field stations according to claim 1 is characterized in that: The inlet and outlet pipelines of the solar thermal collector are provided with a first pressure transmitter.

7. The small-scale light-heat utilization system suitable for oil field stations according to claim 1 is characterized in that: A second pressure transmitter is arranged on the inlet and outlet pipelines of the variable frequency pump.

8. The small-scale light-heat utilization system suitable for oil field stations according to claim 1 is characterized in that: The heat exchanger is provided with a second temperature transmitter, and the second temperature transmitter is interlocked with the variable frequency pump.

9. The small-scale light-heat utilization system applicable to oil field stations according to claim 1 is characterized in that: The heat storage device is provided with a first temperature sensor, and the solar thermal collector is provided with a second temperature sensor; The PLC control cabinet is used to control the heat storage device and the solar collector to stop working when the temperature signal collected by the first temperature sensor is lower than a first preset temperature and the temperature signal collected by the second temperature sensor is lower than a second preset temperature.

10. The small-scale light-heat utilization system applicable to oil field stations according to claim 1 is characterized in that: The heat storage medium of the heat storage device is special-shaped magnesia bricks.

11. The small-scale light-heat utilization system applicable to oil field stations according to claim 1 is characterized in that: The heat transfer medium of the heat exchanger is antifreeze liquid.

12. A small-scale light-heat utilization method suitable for oil field stations, characterized in that: Using the small-scale photothermal utilization system applicable to oil field stations as described in any one of claims 1 to 11, the method comprises: collecting a first temperature signal of a solar thermal collector in real time; When the first temperature signal is greater than or equal to the first operating temperature signal, the solar collector is controlled to exchange heat with the heat exchanger and the excess heat is stored in the heat storage device; and when the temperature signal of the heat exchanger reaches the first operating temperature signal, the heat exchanger is controlled to exchange heat with oilfield produced fluid or crude oil processed by the oilfield station; When the first temperature signal is less than the first working temperature signal, the second working temperature signal of the heat storage device is determined according to the first temperature signal. When the second temperature signal of the heat storage device reaches the second working temperature signal, the variable frequency pump is started, and the frequency of the variable frequency pump is adjusted by the variable frequency speed regulator according to the second working temperature signal, so that the heat medium in the pipeline connecting the variable frequency pump and the heat storage device circulates and heats up until the heat medium is heated to the first working temperature signal, and the heat exchanger is controlled to exchange heat with the oilfield produced fluid or the crude oil processed by the oilfield station.

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