Heat compensation system of greenhouse and method for determining well depth of greenhouse

Abstract

The invention discloses a heat compensation system of a greenhouse, which is characterized in that a biomass boiler module is connected with a geothermal coil pipe arranged under the ground of the greenhouse, a ground source heat pump module is connected with the geothermal coil pipe, and a detection module is used for detecting external temperature information outside the greenhouse, illumination information in the greenhouse and internal temperature information in the greenhouse; the external temperature information, the illumination information and the internal temperature information are sent to the greenhouse heating control module; the greenhouse heating control module is electrically connected with the biomass boiler module and the ground source heat pump module and used for controlling the operation state of the biomass boiler module and the operation state of the ground source heat pump module according to the received external temperature information, illumination information and internal temperature information. Through cooperative work of the ground source heat pump module and the biomass boiler module, the construction cost of the greenhouse can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of geothermal energy application, and in particular to a greenhouse heat supplement system and a method for determining a greenhouse well depth. Background Art

[0002] With the promotion of greenhouses, significant results have been achieved in the cultivation of some economic crops, bringing considerable economic benefits. However, most traditional solar greenhouses use a single ground source heat pump heating method, which has a high construction cost.

[0003] Therefore, there is an urgent need for a heat supplement system for greenhouses to solve the problem of high greenhouse construction costs in the prior art. Summary of the invention

[0004] In view of this, the present invention provides a heat supplement system for a greenhouse and a method for determining the well depth of the greenhouse, the main purpose of which is to solve the problem of high construction costs of greenhouses.

[0005] In order to solve the above problems, the present application provides a greenhouse heat supplement system, comprising:

[0006] The biomass boiler module is connected to the geothermal coil arranged under the greenhouse, and is used to provide heat to the circulating fluid in the geothermal coil by burning biomass fuel, so as to provide heat to the greenhouse;

[0007] A ground source heat pump module is connected to the geothermal coil and is used to provide heat to the circulating fluid in the geothermal coil by heat exchange to provide heat for the greenhouse;

[0008] A detection module, used to detect external temperature information outside the greenhouse, light information inside the greenhouse, and internal temperature information inside the greenhouse, and send the external temperature information, the light information, and the internal temperature information to the greenhouse heating control module;

[0009] The greenhouse heating control module is electrically connected to the biomass boiler module and the ground source heat pump module, respectively, and is used to control the operating state of the biomass boiler module and the operating state of the ground source heat pump module according to the received external temperature information, the light information and the internal temperature information.

[0010] Optionally, the heat supplement system of the greenhouse also includes: a solar module, which is electrically connected to the detection module, the greenhouse heating control module and the ground source heat pump module, respectively, and is used to supply power to the detection module, the greenhouse heating control module and the ground source heat pump module.

[0011] Optionally, the system further comprises: a greenhouse electrical control module;

[0012] The greenhouse electrical control module is electrically connected to the solar module;

[0013] The greenhouse electrical control module is also electrically connected to the detection module and the ground source heat pump module, and is used to control the power supply equipment of the detection module and the ground source heat pump module to switch from the solar module to the power grid system, or from the power grid system to the solar module.

[0014] Optionally, the biomass boiler module includes: a boiler body and a dust collector;

[0015] The boiler body is connected to the geothermal coil through a circulating water pipe, and is used to heat the circulating fluid and transport the circulating fluid to the geothermal coil through the circulating water pipe;

[0016] The dust collector is arranged inside the boiler body and is used to absorb dust generated by combustion.

[0017] Optionally, the ground source heat pump module includes: an outdoor buried pipe heat exchanger, a condenser, a compressor and an evaporator connected in sequence.

[0018] Optionally, the greenhouse heating control module is specifically used for:

[0019] Compare the illumination information obtained by the detection with a preset first illumination intensity standard and a preset second illumination intensity standard respectively, wherein the first illumination intensity standard is less than the second illumination intensity standard;

[0020] When the illumination information is less than or equal to the first illumination intensity standard, controlling the biomass boiler module and the ground source heat pump module to operate simultaneously throughout the day;

[0021] When the illumination information is greater than the first illumination intensity standard and the illumination information is less than the second illumination intensity standard, during a predetermined daytime period, the biomass boiler module is controlled to be turned off and the ground source heat pump module is controlled to operate; during a predetermined nighttime period, the biomass boiler module and the ground source heat pump module are controlled to operate simultaneously;

[0022] When the illumination information is greater than or equal to the second illumination intensity standard, the biomass boiler module is controlled to be turned off, and the ground source heat pump module is controlled to operate all day.

[0023] Optionally, the detection module includes: a first temperature sensor, a second temperature sensor and a light intensity detector;

[0024] The first temperature sensor is arranged inside the greenhouse to detect the ambient temperature of the internal space of the greenhouse and obtain the internal temperature information;

[0025] The second temperature sensor is arranged outside the greenhouse to detect the external ambient temperature of the greenhouse and obtain the external temperature information;

[0026] The light intensity detector is arranged inside the greenhouse to detect the sunlight intensity in the greenhouse and obtain the light information.

[0027] Optionally, the detection module further includes: a third temperature sensor and a fourth temperature sensor;

[0028] The third temperature sensor is arranged at the heat exchange liquid inlet of the geothermal coil and is used to detect the water inlet temperature at the heat exchange liquid inlet of the geothermal coil;

[0029] The fourth temperature sensor is arranged at the heat exchange outlet of the geothermal coil and is used to detect the outlet water temperature at the heat exchange outlet of the geothermal coil;

[0030] The greenhouse heating control module is also electrically connected to the third temperature sensor and the fourth temperature sensor, and is used to receive the inlet water temperature sent by the third temperature sensor and the outlet water temperature sent by the fourth sensor, and control the operating parameters of the biomass boiler module or the ground source heat pump module based on the inlet water temperature and the outlet water temperature.

[0031] Optionally, the detection module further includes: a carbon dioxide concentration detector;

[0032] The carbon dioxide concentration detector is arranged inside the greenhouse and is used to detect the carbon dioxide concentration in the greenhouse.

[0033] Optionally, the circulating fluid is groundwater, and the greenhouse heating system further includes a geothermal well for providing groundwater;

[0034] The system further comprises a depth determination module for determining the depth of the geothermal well, wherein the depth determination module is configured to:

[0035] Obtain the heating design temperature outside the greenhouse and determine the expected heating temperature inside the greenhouse;

[0036] At least based on the heating design temperature and the expected heating temperature, respectively determine the total heat transfer of the greenhouse enclosure structure, the cold wind infiltration heat loss of the greenhouse, and the total heat transfer of the ground of the greenhouse;

[0037] Determining the target heat to be generated by the ground source heat pump module based on the total heat transfer of the enclosure structure, the cold air infiltration heat loss and the total heat transfer of the ground;

[0038] The depth of the geothermal well is determined based on the target heat and the heat discharged per unit hole depth.

[0039] In order to solve the above problems, the present application provides a method for determining the well depth of a greenhouse, comprising:

[0040] Obtain the heating design temperature outside the greenhouse and determine the expected heating temperature inside the greenhouse;

[0041] At least based on the heating design temperature and the expected heating temperature, respectively determine the total heat transfer of the greenhouse enclosure structure, the cold wind infiltration heat loss of the greenhouse, and the total heat transfer of the ground of the greenhouse;

[0042] Determining the target heat to be generated by the ground source heat pump module based on the total heat transfer of the enclosure structure, the cold air infiltration heat loss and the total heat transfer of the ground;

[0043] The depth of the geothermal well is determined based on the target heat and the heat discharged per unit hole depth.

[0044] Optionally, the total heat transfer of the greenhouse enclosure structure, the cold wind infiltration heat loss of the greenhouse, and the total heat transfer of the greenhouse ground are determined respectively based on at least the heating design temperature and the expected heating temperature, specifically including:

[0045] Determining the total heat transfer of the enclosure structure based on the heating design temperature, the expected heating temperature, the heat transfer coefficient of the greenhouse maintenance structure, and the heat transfer area of ​​the greenhouse maintenance structure;

[0046] Determine the cold air infiltration heat loss based on the heating design temperature, the expected heating temperature, the constant pressure specific heat of the air, and the air exchange rate between the greenhouse and the outside;

[0047] The total ground heat transfer amount is determined based on the heating design temperature, the expected heating temperature, the ground heat transfer coefficient and the ground area.

[0048] Optionally, determining the target heat to be generated by the ground source heat pump module based on the total heat transfer of the enclosure structure, the cold air infiltration heat loss and the total heat transfer of the ground specifically includes:

[0049] Determine the expected heat required for the greenhouse based on the total heat transfer of the enclosure structure, the cold air penetration heat loss, the total heat transfer of the ground, the structural additional coefficient and the wind additional coefficient;

[0050] The target heat to be generated by the ground source heat pump module is determined based on the expected heat.

[0051] Optionally, determining the depth of the geothermal well based on the target heat and the heat discharged per unit hole depth specifically includes:

[0052] determining the amount of heat that the ground source heat pump absorbs from the soil based on the target heat;

[0053] The depth of the geothermal well is determined based on the amount of heat the ground source heat pump absorbs from the soil and the amount of heat discharged per unit hole depth.

[0054] A heat supplement system for a greenhouse in the present application provides heating services for the greenhouse through the coordinated work of a ground source heat pump module and a biomass boiler module, thereby reducing the construction investment of the ground source heat pump module, thereby avoiding the problem of high construction costs caused by the single use of a ground source heat pump module for heating, and reducing the construction cost of the greenhouse. In addition, by setting up a detection module and a greenhouse heating control module, it is possible to monitor the temperature inside and outside the greenhouse in real time, and intelligently control the combustion time and fuel consumption of the biomass boiler, while accurately controlling the amount of underground hot water extracted by the ground source heat pump, which can ensure that the crop growth environment is always in the optimal temperature conditions, and realizes the precise control of the greenhouse temperature.

[0055] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0057] Figure 1 This is a structural block diagram of a heat supplement system for a greenhouse according to an embodiment of the present application;

[0058] Figure 2 This is a structural block diagram of a ground source heat pump module in another embodiment of the present application. DETAILED DESCRIPTION

[0059] Various aspects and features of the present application are described herein with reference to the accompanying drawings.

[0060] It should be understood that various modifications may be made to the embodiments of the present application. Therefore, the above description should not be considered as limiting, but only as an example of an embodiment. Other modifications within the scope and spirit of the present application will occur to those skilled in the art.

[0061] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0062] These and other characteristics of the present application will become apparent from the following description of a preferred form of embodiment given as a non-limiting example with reference to the accompanying drawings.

[0063] It should also be understood that although the present application has been described with reference to some specific examples, those skilled in the art will be able to readily implement many other equivalent forms of the present application.

[0064] The above and other aspects, features and advantages of the present application will become more apparent in view of the following detailed description when taken in conjunction with the accompanying drawings.

[0065] Specific embodiments of the present application are described hereinafter with reference to the accompanying drawings; however, it should be understood that the embodiments applied for are merely examples of the present application, which may be implemented in a variety of ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that obscure the present application. Therefore, the specific structural and functional details applied for herein are not intended to be limiting, but merely serve as a basis and representative basis for the claims to teach those skilled in the art to use the present application in a variety of ways with substantially any suitable detailed structure.

[0066] This specification may use the phrases "in one embodiment," "in another embodiment," "in yet another embodiment," or "in other embodiments," all of which may refer to one or more of the same or different embodiments according to the present application.

[0067] This embodiment proposes a greenhouse heating system, such as Figure 1 As shown, it includes: a biomass boiler module 2, which is connected to a geothermal coil 3 arranged under the greenhouse 1, and is used to provide heat for the circulating fluid in the geothermal coil 3 by burning biomass fuel, so as to provide heat for the greenhouse 1;

[0068] The ground source heat pump module 4 is connected to the geothermal coil 3 and is used to provide heat to the circulating fluid in the geothermal coil by heat exchange to provide heat to the greenhouse; the detection module ( Figure 1(not shown), for detecting external temperature information outside the greenhouse, light information inside the greenhouse, and internal temperature information inside the greenhouse, and sending the external temperature information, the light information, and the internal temperature information to the greenhouse heating control module; the greenhouse heating control module ( Figure 1 Not shown), which are electrically connected to the biomass boiler module and the ground source heat pump module, respectively, and are used to control the operating state of the biomass boiler module and the operating state of the ground source heat pump module according to the received external temperature information, the light information and the internal temperature information.

[0069] In this embodiment, the greenhouse 1 is a light-transmitting and heat-insulating closed structure used as a greenhouse environment for the growth of crops, and includes a wall 11 and a heat-insulating film 12 of the greenhouse 1.

[0070] The greenhouse heat supplement system in this embodiment provides heating services for the greenhouse through the coordinated work of the ground source heat pump module and the biomass boiler module, thereby reducing the construction investment of the ground source heat pump module, thereby avoiding the high construction cost caused by the single use of the ground source heat pump module for heating, and reducing the construction cost of the greenhouse. In addition, by setting up a detection module and a greenhouse heating control module, it is possible to monitor the temperature inside and outside the greenhouse in real time, intelligently control the combustion time and fuel consumption of the biomass boiler, and accurately control the amount of underground hot water extracted by the ground source heat pump to ensure that the crop growth environment is always in the optimal temperature conditions, thereby achieving precise control of the greenhouse temperature.

[0071] Another embodiment of the present application provides a heat supplement system for a greenhouse, the system also includes: a solar module 5, which is arranged above the greenhouse 1 and connected to the greenhouse heating control module, so that the system can fully absorb and utilize solar energy, provide heat and electricity for the greenhouse system, and meet the growth conditions of crops in the greenhouse. Specifically, the solar module 5 is electrically connected to the detection module, the greenhouse heating control module and the ground source heat pump module respectively, and is used to power the detection module, the greenhouse heating control module and the ground source heat pump module. In this embodiment, the solar cell module 5 includes a photovoltaic solar panel 51, a solar collector 52 and a power storage unit 53. Among them, the photovoltaic solar panel 51 is placed on the top of the greenhouse, and is electrically connected to the heat storage unit 53, the lighting equipment 6, the detection module and the ground source heat pump module, absorbing and utilizing solar energy, and powering the lighting equipment 6, the detection module and the ground source heat pump module of the greenhouse. The solar collector 52 is placed on the top of the greenhouse, and is used to convert solar energy into thermal energy, which is used to heat the water in the pipeline and heat the greenhouse. The power storage unit 53 is connected to the photovoltaic solar panel and is used to store the electric energy converted by the photovoltaic solar panel, playing the role of storing electric energy in the system.

[0072] In this embodiment, the ground source heat pump module 4, the power storage unit 53, and the photovoltaic solar panel 51 are connected in sequence through wires to form a closed loop. A transformer 7 is connected between the power storage unit and the ground source heat pump. The electric energy generated by the photovoltaic solar panel 51 is stored in the power storage unit 53 when not in use. When the system needs electricity, the electricity in the power storage unit 53 is converted into the required electric energy through the transformer 7 and transmitted to the ground source heat pump module 4 through the wire. In this embodiment, by setting the solar module, the operating cost of the system can be reduced.

[0073] On the basis of the above embodiments, another embodiment of the present application provides a greenhouse heating system, the system further comprising: a greenhouse electrical control module; the greenhouse electrical control module is electrically connected to the solar module 5; the greenhouse electrical control module is also electrically connected to the detection module and the ground source heat pump module 4, and is used to control the power supply equipment of the detection module and the ground source heat pump module to switch from the solar module to the power grid system, or from the power grid system to the solar module. That is, the greenhouse electrical control module ( Figure 1 Not shown in the figure), which are respectively connected to the solar cell module 5, the ground source heat pump module 4 and the detection module. According to the system operation status controlled by the greenhouse heating control system, it is judged whether the electricity generated by the solar cell module can meet the power supply demand of the entire system, and it is decided whether to connect to the power grid to ensure the normal operation of the entire system.

[0074] That is to say, the greenhouse electrical control module in this embodiment is provided with an electricity control standard. The electricity consumed by the operation of the ground source heat pump is n1, and the electricity consumed by the lighting equipment block lighting, detection module, etc. is n2. According to the comparison between the sum of n1 and n2, N1, and the electricity generated by the photovoltaic solar panel, N2, it is determined whether it is necessary to connect to the power grid to supplement the electric energy. The specific setting is N1=n1+n2. When N1≤N2, the greenhouse electrical control module determines that the electricity generated by the photovoltaic solar panel is sufficient to meet the operating requirements of the system, so it controls the grid connection to be closed, and there is no need to provide additional electricity for the greenhouse. When N1>N2, the greenhouse electrical control module determines that the electricity generated by the photovoltaic solar panel is insufficient to meet the operating requirements of the system. At this time, the grid connection will be opened, the grid will be connected, and the power of the grid will be used to ensure the normal operation of the system.

[0075] Preferably, the biomass boiler module 2 in this embodiment includes: a boiler body 21 and a dust collector; the boiler body is connected to the geothermal coil 3 through a circulating water pipe, which is used to heat the circulating fluid and transport the circulating fluid to the geothermal coil 3 through the circulating water pipe; the boiler body 21 is used to burn biomass fuel to provide heat energy for the system. The dust collector is arranged inside the boiler body to absorb dust generated by combustion.

[0076] Preferably, the ground source heat pump module 4 comprises: an outdoor buried pipe heat exchanger 43, a condenser 46, a compressor 45 and an evaporator 44 which are connected in sequence.

[0077] The outdoor buried heat exchanger 43 is buried underground, and performs heat exchange with underground soil or groundwater through circulating liquid (such as water) in the pipe, thereby absorbing or releasing heat.

[0078] The evaporator 44 is arranged between the compressor 45 and the geothermal coil 3. Through efficient heat exchange with the external environment, the refrigerant is transformed from a high-temperature and high-pressure gas state to a low-temperature and low-pressure gas state, thereby achieving a significant refrigeration effect. By accurately controlling the working parameters of the evaporator, the temperature and pressure of the refrigerant can be flexibly adjusted, thereby achieving multiple goals such as constant temperature, constant humidity, and constant pressure, ensuring the stability and efficiency of the system operation.

[0079] The compressor 45 is arranged between the condenser 46 and the evaporator 44 to increase the pressure and temperature of the refrigerant to ensure that it circulates efficiently in the system and transfers heat. Through this process, the compressor releases heat to the water-side heat exchanger, thereby generating hot water.

[0080] The condenser 46 is arranged between the heat exchanger 43 and the compressor 45, ensuring that the refrigerant can be efficiently converted from gas to liquid while releasing a large amount of heat, which not only provides the necessary pressure control for the normal operation of the system, but also realizes the effective recovery of energy, thereby improving the overall energy efficiency and stability of the system.

[0081] Specifically, Figure 2 As shown, the ground source heat pump module 4 extracts heat from the underground heat exchange system, raises the heat to a temperature level suitable for heating through the condensation process of the refrigerant in the condenser 46, and then transports it to the interior of the building. The refrigerant absorbs heat from the soil or groundwater in the underground circulation and evaporates, and is compressed into a high-temperature and high-pressure gas by the compressor 45, and then releases heat in the evaporator 44 to heat the building, and then the refrigerant condenses and flows back to the underground to continue circulating. A circulating water pump 48 is provided on one side of the buried heat exchanger, and a circulating water pump 47 and a return valve 62 are provided on the geothermal coil side. The outdoor buried heat exchanger of the system of the present invention is connected to the circulating water pump 48, the condenser 46, the compressor 45, the evaporator 44, the circulating water pump 41 and the check valve 42 in sequence, and then connected back to the ground source heat pump by connecting the geothermal coil 3, the circulating water pump 47, and the return valve 49 in the greenhouse to realize the circulation of hot water.

[0082] In this embodiment, the geothermal coil 3 is a serpentine coil evenly distributed under the greenhouse. The geothermal coil can realize heat exchange between the air in the greenhouse and the hot water in the pipeline, thereby adjusting the temperature of the greenhouse. The two ends of the geothermal coil are respectively provided with a heat exchange liquid inlet 31 and a heat exchange liquid outlet 32 ​​to ensure that the heat conductor can effectively flow in the pipeline.

[0083] In the specific implementation process of this embodiment, the biomass boiler module 2 is provided with a circulation pump 22, the circulation pump 22 is provided with a regulating valve 24, a check valve 25 is provided behind the circulation pump 22, and a second return valve 26 is provided behind the heat exchange outlet 32. The biomass boiler body 21 of the system of the present invention is connected to the circulation pump 22 and the heat exchange inlet 32 ​​in sequence through a circulation water pipe, and then connected back to the biomass boiler body 21 through the heat exchange outlet 32 ​​and the second return valve 26, so as to realize the circulation heating of hot water. The hot water heated by biomass combustion is sent to the geothermal coil through the circulation pump, and the exchanged water is sent back to the biomass boiler through the heat exchange outlet for heating and recycling.

[0084] Preferably, the greenhouse heating control module in this embodiment is specifically used to: compare the light information obtained by detection with a preset first light intensity standard L1 and a preset second light intensity standard L2, wherein the first light intensity standard L1 is less than the second light intensity standard L2;

[0085] When the light information is less than or equal to the first light intensity standard L1, control the biomass boiler module 2 and the ground source heat pump module 4 to operate simultaneously throughout the day;

[0086] When the light information is greater than the first light intensity standard L1 and less than the second light intensity standard L2, within a predetermined daytime period, control the biomass boiler module 2 to shut down and control the ground source heat pump module 4 to operate, and within a predetermined nighttime period, control the biomass boiler module 2 and the ground source heat pump module to operate simultaneously;

[0087] When the light information is greater than or equal to the second light intensity standard L2, control the biomass boiler module to shut down and control the ground source heat pump module to operate throughout the day.

[0088] In addition, the detection module in this embodiment includes a first temperature sensor, a second temperature sensor, and a light intensity detector. The first temperature sensor is arranged inside the greenhouse, used to detect the ambient temperature inside the greenhouse and obtain the internal temperature information; the second temperature sensor is arranged outside the greenhouse, used to detect the ambient temperature outside the greenhouse and obtain the external temperature information; the light intensity detector is arranged inside the greenhouse, used to detect the sunlight intensity inside the greenhouse and obtain the light information.

[0089] Preferably, the detection module further includes: a third temperature sensor and a fourth temperature sensor; the third temperature sensor is arranged at the heat exchange liquid inlet of the geothermal coil 3, used to detect the inlet water temperature at the heat exchange liquid inlet 31 of the geothermal coil 3; the fourth temperature sensor is arranged at the heat exchange liquid outlet 32 of the geothermal coil 3, used to detect the outlet water temperature at the heat exchange liquid outlet 32 of the geothermal coil 3.

[0090] In this embodiment, the greenhouse heating control module is also electrically connected to the third temperature sensor and the fourth temperature sensor, used to receive the inlet water temperature sent by the third temperature sensor and the outlet water temperature sent by the fourth sensor, and control the operating parameters of the biomass boiler module 2 or the solar cell module 5 based on the inlet water temperature and the outlet water temperature. The detection module further includes: a carbon dioxide concentration detector; the carbon dioxide concentration detector is arranged inside the greenhouse 1, used to detect the carbon dioxide concentration inside the greenhouse. In this embodiment, when it is detected that the carbon dioxide concentration PPM1 inside the greenhouse is less than the preset carbon dioxide concentration PPM2 (i.e., PPM1 < PPM2), control the carbon dioxide recovery device to release carbon dioxide through the carbon dioxide release device to supplement the carbon dioxide in the greenhouse

[0091] In this embodiment, the circulating fluid is groundwater, and the heating system of the greenhouse 1 also includes a geothermal well for providing groundwater; the greenhouse heating system in this embodiment also includes a depth determination module for determining the depth of the geothermal well, and the depth determination module is used to: obtain the heating design temperature T outside the greenhouse w , and determine the expected heating temperature T in greenhouse 1 n ; At least based on the heating design temperature and the expected heating temperature, determine the total heat transfer Q1 of the enclosure structure of greenhouse 1, the cold air infiltration heat loss Q2 of greenhouse 1 and the total heat transfer Q3 of the ground of greenhouse 1 respectively; based on the total heat transfer Q1 of the enclosure structure, the cold air infiltration heat loss Q2 and the total heat transfer Q3 of the ground, determine the heat to be generated by the entire heating system; then determine the depth of the geothermal well based on the heat to be generated by the entire heating system and the heat discharged per unit hole depth.

[0092] In this embodiment, when the depth determination module determines the depth of the geothermal well, the specific process is as follows:

[0093] Step 1: Get the heating design temperature T outside the greenhouse w , and determine the expected heating temperature T in the greenhouse n ;

[0094] In this step, the heating design temperature T outside the greenhouse can be determined based on the historical temperature of the area where the greenhouse is located and the optimal growth temperature of the planted plants. w , and determine the expected heating temperature T in the greenhouse n .

[0095] Step 2: Based at least on the heating design temperature and the expected heating temperature, determine the total heat transfer Q1 of the greenhouse enclosure structure, the cold air infiltration heat loss Q2 of the greenhouse, and the total heat transfer Q3 of the greenhouse ground.

[0096] In this step, the following first calculation formula can be used to calculate the total heat transfer Q1 of the greenhouse enclosure structure;

[0097] Q1=∑K1F1(T n -T w ) (1)

[0098] Among them, Q1 is the total heat transfer of all greenhouse enclosure structures, including the heat transfer of external enclosure structures such as roofs, walls, doors, windows, etc., in W; K1 is the heat transfer coefficient of the greenhouse maintenance structure (roof, walls, doors, windows, etc.), in W / (m 2 ·K); F1 is the heat transfer area of ​​the greenhouse maintenance structure (roof, wall, door, window, etc.), unit is m 2 ; T n 、T wThey are the indoor and outdoor heating design temperatures of the greenhouse, in °C.

[0099] In this step, the following second calculation formula can be used to calculate the cold air penetration heat loss Q2 of the greenhouse;

[0100] Q2=C P m(T n -T w )=C P NVУ(T n -T w ) (2)

[0101] Among them, Q2 is the heat loss of greenhouse cold air penetration, unit is W; C P is the constant pressure specific heat of air (which can be obtained by looking up the table of constant pressure specific heat of air at different temperatures); m is the mass of air that penetrates into the greenhouse by cold wind, in kg; m = NVУ is the air exchange rate between the greenhouse and the outside world, also known as the number of ventilations, in units of complete ventilations per hour; N is the air heat exchange rate between the greenhouse and the outside world, that is, the number of ventilations, in units of complete ventilations per hour; V is the internal volume of the greenhouse, in m 3 ; У is the specific gravity of air, in kg / m 3 .

[0102] In this step, the third calculation formula below can be used to calculate the total heat transfer Q3 of the greenhouse ground.

[0103] Q3=∑K i F i (T n -T w ) (3)

[0104] Where Q3 is the total heat transfer through the greenhouse floor, in W; K i is the ground heat transfer coefficient of the i-th zone, in W / (m 2 ·K); F i is the ground area of ​​the ith zone, in m 2 ; T n 、T w They are the indoor and outdoor heating design temperatures of the greenhouse, in °C.

[0105] Step 3: Determine the target heat to be generated by the ground source heat pump module based on the total heat transfer of the enclosure structure Q1, the cold air infiltration heat loss Q2 and the total heat transfer of the ground Q3

[0106] In the specific implementation process of this step, the heat required by the greenhouse (the expected heat required by the greenhouse) Q can be calculated using the fourth calculation formula based on the total heat transfer of the enclosure structure Q1, the cold air penetration heat loss Q2 and the total heat transfer of the ground Q3. 需 Then according to the heat required by the greenhouse (the expected heat required by the greenhouse) Q 需 , use the fifth calculation formula to determine the target heat Q to be generated by the ground source heat pump module 地源热泵 .

[0107] Specifically, the fourth calculation formula may be:

[0108] Q 需 =α1α2Q1+Q2+Q3 (4)

[0109] Among them, α1 is the structural additional coefficient; α2 is the wind additional coefficient, and both α1 and α2 are obtained from the "Design Code for Heating, Ventilation and Air Conditioning of Civil Buildings GB50736-2012"; Q1 is the total heat transfer through all enclosing structures of the greenhouse, in W; Q2 is the cold air infiltration heat load / cold air infiltration heat loss of the greenhouse, in W; Q3 is the ground heat transfer of the greenhouse, in W.

[0110] In this embodiment, the fifth calculation formula is:

[0111] Q 地源热泵 =60%Q 需 (5)

[0112] in,

[0113] Step 4: Determine the depth of the geothermal well based on the target heat and the heat discharged per unit hole depth;

[0114] In this step, after determining the target heat, the target heat can be calculated using the sixth calculation formula as the heat absorbed by the ground source heat pump from the soil. Then the ground source heat pump is used to absorb the heat from the soil The depth of the geothermal well is calculated using the seventh calculation formula.

[0115] Among them, the sixth calculation formula is:

[0116]

[0117] Among them, Q 地源热泵 is the target heat, and COP is the heating coefficient of the ground source heat pump unit under the design conditions.

[0118] The seventh calculation formula is:

[0119]

[0120] Wherein, L is the total depth of the geothermal well, in m; is the heat absorbed from the soil in winter, in W; W1 is the heat discharged per unit hole depth, in W / m.

[0121] In this embodiment, the depth of the geothermal well is determined by the well depth determination module in the above manner, which can make the depth determination more reasonable and accurate, and lay a foundation for the subsequent establishment of a geothermal well based on the geothermal well depth, and for providing circulating fluid for the greenhouse heating system based on the groundwater in the geothermal well, which is conducive to the accurate and reliable operation of the greenhouse heating system.

[0122] Another embodiment of the present application provides a method for determining a well depth of a greenhouse, comprising:

[0123] Step S101, obtaining the heating design temperature outside the greenhouse and determining the expected heating temperature inside the greenhouse;

[0124] Step S102, determining the total heat transfer of the greenhouse enclosure structure, the cold air infiltration heat loss of the greenhouse, and the total heat transfer of the greenhouse ground at least based on the heating design temperature and the expected heating temperature;

[0125] Step S103, determining the target heat to be generated by the ground source heat pump module based on the total heat transfer of the enclosure structure, the cold air infiltration heat loss and the total heat transfer of the ground;

[0126] Step S104, determining the depth of the geothermal well based on the target heat and the heat discharged per unit hole depth.

[0127] In the specific implementation process of this embodiment, when executing step S102, the total heat transfer of the enclosure structure can be determined by a first calculation formula based on the heating design temperature, the expected heating temperature, the heat transfer coefficient of the greenhouse maintenance structure, and the heat transfer area of ​​the greenhouse maintenance structure; the cold air infiltration heat loss can be determined by a second calculation formula based on the heating design temperature, the expected heating temperature, the constant-pressure specific heat of the air, and the air exchange rate between the greenhouse and the outside world; the total ground heat transfer can be determined by a third calculation formula based on the heating design temperature, the expected heating temperature, the ground heat transfer coefficient, and the ground area.

[0128] The first calculation formula is: Q1 = ∑K1F1(T n -T w ) Among them, Q1 is the total heat transfer of all greenhouse enclosure structures, including the heat transfer of external enclosure structures such as roof, wall, door, window, etc., unit is W; K1 is the heat transfer coefficient of greenhouse maintenance structure (roof, wall, door, window, etc.), unit is W / (m 2·K); F1 is the heat transfer area of ​​the greenhouse maintenance structure (roof, wall, door, window, etc.), unit is m 2 ; T n , T w They are the indoor and outdoor heating design temperatures of the greenhouse, in °C.

[0129] The second calculation formula is: Q2 = C P m(T n -T w )=C P NVУ(T n -T w ), where Q2 is the heat loss of greenhouse cold air penetration, in W; C P is the constant pressure specific heat of air (which can be obtained by looking up the table of constant pressure specific heat of air at different temperatures); m is the mass of air that penetrates into the greenhouse by cold wind, in kg; m = NVУ is the air exchange rate between the greenhouse and the outside world, also known as the number of ventilations, in units of complete ventilations per hour; N is the air heat exchange rate between the greenhouse and the outside world, that is, the number of ventilations, in units of complete ventilations per hour; V is the internal volume of the greenhouse, in m 3 ; У is the specific gravity of air, in kg / m 3 .

[0130] The third calculation formula is: Q3 = ∑K i F i (T n -T w ), where Q3 is the total heat transfer through the greenhouse floor, in W; K i is the ground heat transfer coefficient of the i-th zone, in W / (m 2 ·K); F i is the ground area of ​​the ith zone, in m 2 ; T n , T w They are the indoor and outdoor heating design temperatures of the greenhouse, in °C.

[0131] In the specific implementation process of this embodiment, when executing step S103, that is, based on the total heat transfer of the enclosure structure, the cold air infiltration heat loss and the total heat transfer of the ground, the target heat to be generated by the ground source heat pump module is determined, specifically including:

[0132] Based on the total heat transfer of the enclosure structure, the cold air penetration heat loss, the total heat transfer of the ground, the structural additional coefficient and the wind additional coefficient, the expected heat required for the greenhouse is determined using the fourth calculation formula Q 需 Based on the expected heat Q 需 , use the fifth calculation formula to determine the target heat to be generated by the ground source heat pump module.

[0133] Among them, the fourth calculation formula is: Q 需 =α1α2Q1+Q2+Q3, where α1 is the structural additional coefficient; α2 is the wind additional coefficient, and both α1 and α2 are obtained from the "Design Code for Heating, Ventilation and Air Conditioning of Civil Buildings GB50736-2012"; Q1 is the total heat transfer through all the enclosing structures of the greenhouse, in W; Q2 is the cold air infiltration heat load / cold air infiltration heat loss of the greenhouse, in W; Q3 is the ground heat transfer of the greenhouse, in W.

[0134] The fifth calculation formula is: Q 地源热泵 =60%Q 需 ,

[0135] In the specific implementation process of this embodiment, when executing step S104, that is, when determining the depth of the geothermal well based on the target heat and the heat dissipated per unit hole depth, it specifically includes: based on the target heat, using the sixth calculation formula to determine the heat absorbed by the ground source heat pump from the soil; based on the heat absorbed by the ground source heat pump from the soil and the heat dissipated per unit hole depth, using the seventh calculation formula to determine the depth of the geothermal well.

[0136] Among them, the sixth calculation formula is: Q 地源热泵 is the target heat, and COP is the heating coefficient of the ground source heat pump unit under the design conditions.

[0137] The seventh calculation formula is: Wherein, L is the total depth of the geothermal well, in m; is the heat absorbed from the soil in winter, in W; W1 is the heat discharged per unit hole depth, in W / m.

[0138] In this embodiment, by adopting the above-mentioned method to determine the depth of the geothermal well, the depth can be determined more reasonably and accurately, which lays the foundation for the subsequent establishment of a geothermal well based on the depth of the geothermal well and the provision of circulating fluid for the indoor greenhouse's heating system based on the groundwater in the geothermal well, which is beneficial to ensure the accurate and reliable operation of the indoor greenhouse's heating system.

[0139] The depth determination process in this embodiment is further explained below in conjunction with specific application scenarios. Taking a greenhouse near Lake Khanka as an example, the dimensions of the greenhouse are 45m*8m*4m in length, width and height, and it uses a steel structure + single-layer plastic film. In this case, the main function of the greenhouse is to grow seedlings. If there is no plan to grow specific varieties, the indoor design temperature of the heating system should be designed for thermophilic crops. For thermophilic crops, the minimum temperatures required for crops, vegetables and flowers may be different. According to the information, the minimum temperature for rice seedlings to germinate is 10-12°C, and the optimum is 28-32°C. In this system, the heating temperature T in the greenhouse is taken. nThe design temperature of the greenhouse heating is T w It is -5℃.

[0140] For a single material maintenance structure, the heat transfer coefficient K of the material can be directly obtained from the relevant manual. Take a single layer of plastic film 6.8W / (m 2 ·K).

[0141] When the time is 2-4, the heat required by the greenhouse is:

[0142] From the first calculation formula, Q1=∑K1F1(T n -T w )==138174.749W

[0143] The volume of the arched greenhouse is calculated as a rectangular parallelepiped, and it is calculated that V = 45 × 8 × 4 = 1440m 3

[0144] From the second calculation formula, we get: Q2 = C P m(T n -T w )=C P NVУ(T n -T w )=17447.64W

[0145] From the third calculation formula, we get: Q3 = ∑K i F i (T n -T w )=2816.22W

[0146] According to the fourth calculation formula, Q 需 =α1α2Q1+Q2+Q3=161202.104W

[0147] From the information, we know that the area where Lake Khanka belongs is the Khanka Lake Basin, the heat dissipation per unit hole depth W1 is 112W / m, and the geothermal gradient is 3.5℃ / 100m. In the following examples, it is assumed that the groundwater temperature is the same as the ground temperature at the drilling depth.

[0148] Take a heat exchanger model RSAFV130HD1 as an example: the nominal heating capacity of this model is 150KW, the heating input power is 46.6KW, and the nominal hot water flow rate is 25.8m 3 / h, COP=3.2.

[0149] When the heating scheme of this system is adopted, the ground source heat pump system provides 60% of the heat of the greenhouse, and the fifth and sixth calculation formulas are as follows:

[0150] Finally, according to the seventh calculation formula,

[0151] Therefore, in order to prevent insufficient heating, the geothermal well needs to reach a depth of 1,150 meters.

[0152] The water temperature at this time

[0153] According to the weather conditions in the Xingkai Lake area over the years, the greenhouse outdoor heating design temperature T is taken from 12:00 to 14:00 in the afternoon of a certain day. w The outdoor heating design temperature T of the greenhouse from 2 to 4 am is 15℃. w 3℃. Calculate the electricity consumed by the ground source heat pump operation. Among them, the greenhouse outdoor heating design temperature T from 12:00 to 14:00 in the afternoon of a certain day w When the temperature is 15℃, the heat required by the ground source heat pump is obtained from formulas (2), (3), (4), (5), (6), and (7):

[0154]

[0155] The specific heat capacity of water is known to be c = 4186 J / (kg·℃), and the temperature difference at this time is Δt = T d -T w =40.25-28=12.25℃, c=4186J / (kg·℃), and substituting it into formula (9) yields: m=0.97kg / s=3.51m 3 / h. That is, the amount of underground hot water that needs to be pumped is 3.51m 3 / h to meet the heating needs of the greenhouse.

[0156] Among them, the greenhouse outdoor heating design temperature T w When the temperature is 3℃, the heat required by the ground source heat pump is obtained from formulas (1), (2), (3), (4), (5), and (6): Similarly, the temperature difference Δt at this time is 12.25℃, c=4186J / (kg·℃), and substituting it into formula (8) yields: m=1.88kg / s=6.75m 3 / h, that is, the amount of underground hot water that needs to be pumped is 6.75m 3 / h to meet the heating needs of the greenhouse.

[0157] Assuming that the power of the heat pump is proportional to the water flow rate (this is a simplified assumption, the actual situation may be more complicated), the proportional relationship can be used to calculate the actual power consumption:

[0158] At 12:00-14:00 in the afternoon, the amount of electricity consumed to meet the heating needs of the greenhouse is:

[0159] At 2-4 am, the amount of electricity consumed to meet the greenhouse's heating needs is:

[0160] Compared with the heat supply when the 2-4 state is maintained, this system adjusts the water pumping volume, saving 11.7KWh of electricity and conserving resources.

[0161] The above embodiments are only exemplary embodiments of the present application and are not intended to limit the present application. The protection scope of the present application is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present application within the essence and protection scope of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present application.

Claims

1. A heat supplement system for a greenhouse, characterized in that: include: The biomass boiler module is connected to the geothermal coil arranged under the greenhouse, and is used to provide heat to the circulating fluid in the geothermal coil by burning biomass fuel, so as to provide heat to the greenhouse; A ground source heat pump module is connected to the geothermal coil and is used to provide heat to the circulating fluid in the geothermal coil by heat exchange to provide heat to the greenhouse; A detection module, used to detect external temperature information outside the greenhouse, light information inside the greenhouse, and internal temperature information inside the greenhouse, and send the external temperature information, the light information, and the internal temperature information to the greenhouse heating control module; The greenhouse heating control module is electrically connected to the biomass boiler module and the ground source heat pump module, respectively, and is used to control the operating state of the biomass boiler module and the operating state of the ground source heat pump module according to the received external temperature information, the light information and the internal temperature information.

2. The system according to claim 1, characterized in that The system also includes: a solar module, which is electrically connected to the detection module, the greenhouse heating control module and the ground source heat pump module respectively, and is used to supply power to the detection module, the greenhouse heating control module and the ground source heat pump module.

3. The system according to claim 2, characterized in that The system also includes: a greenhouse electrical control module; The greenhouse electrical control module is electrically connected to the solar module; The greenhouse electrical control module is also electrically connected to the detection module and the ground source heat pump module, and is used to control the power supply equipment of the detection module and the ground source heat pump module to switch from the solar module to the power grid system, or from the power grid system to the solar module.

4. The system according to claim 1, characterized in that: The biomass boiler module includes: a boiler body and a dust collector; The boiler body is connected to the geothermal coil through a circulating water pipe, and is used to heat the circulating fluid and transport the circulating fluid to the geothermal coil through the circulating water pipe; The dust collector is arranged inside the boiler body and is used to absorb dust generated by combustion.

5. The system according to claim 1, wherein: The ground source heat pump module comprises: an outdoor buried pipe heat exchanger, a condenser, a compressor and an evaporator which are connected in sequence.

6. The system according to claim 1, wherein: The greenhouse heating control module is specifically used for: Compare the illumination information obtained by the detection with a preset first illumination intensity standard and a preset second illumination intensity standard respectively, wherein the first illumination intensity standard is less than the second illumination intensity standard; When the illumination information is less than or equal to the first illumination intensity standard, controlling the biomass boiler module and the ground source heat pump module to operate simultaneously throughout the day; When the illumination information is greater than the first illumination intensity standard and the illumination information is less than the second illumination intensity standard, during a predetermined daytime period, the biomass boiler module is controlled to be turned off and the ground source heat pump module is controlled to operate; during a predetermined nighttime period, the biomass boiler module and the ground source heat pump module are controlled to operate simultaneously; When the illumination information is greater than or equal to the second illumination intensity standard, the biomass boiler module is controlled to be turned off, and the ground source heat pump module is controlled to operate all day.

7. The system according to claim 1, characterized in that The circulating fluid is groundwater, and the greenhouse heating system also includes a geothermal well for providing groundwater; The system further comprises a depth determination module for determining the depth of the geothermal well, wherein the depth determination module is configured to: Obtain the heating design temperature outside the greenhouse and determine the expected heating temperature inside the greenhouse; At least based on the heating design temperature and the expected heating temperature, respectively determine the total heat transfer of the greenhouse enclosure structure, the cold wind infiltration heat loss of the greenhouse, and the total heat transfer of the ground of the greenhouse; Determining the target heat to be generated by the ground source heat pump module based on the total heat transfer of the enclosure structure, the cold air infiltration heat loss and the total heat transfer of the ground; The depth of the geothermal well is determined based on the target heat and the heat discharged per unit hole depth.

8. A method for determining the depth of a greenhouse well, characterized in that: include: Obtain the heating design temperature outside the greenhouse and determine the expected heating temperature inside the greenhouse; At least based on the heating design temperature and the expected heating temperature, respectively determine the total heat transfer of the greenhouse enclosure structure, the cold wind infiltration heat loss of the greenhouse, and the total heat transfer of the ground of the greenhouse; Determining the target heat to be generated by the ground source heat pump module based on the total heat transfer of the enclosure structure, the cold air infiltration heat loss and the total heat transfer of the ground; The depth of the geothermal well is determined based on the target heat and the heat discharged per unit hole depth.

9. The method according to claim 7, characterized in that The method of determining the total heat transfer of the greenhouse enclosure structure, the cold wind infiltration heat loss of the greenhouse, and the total heat transfer of the ground of the greenhouse based at least on the heating design temperature and the expected heating temperature specifically includes: Determining the total heat transfer of the enclosure structure based on the heating design temperature, the expected heating temperature, the heat transfer coefficient of the greenhouse maintenance structure, and the heat transfer area of ​​the greenhouse maintenance structure; Determine the cold air infiltration heat loss based on the heating design temperature, the expected heating temperature, the constant pressure specific heat of the air, and the air exchange rate between the greenhouse and the outside; The total ground heat transfer amount is determined based on the heating design temperature, the expected heating temperature, the ground heat transfer coefficient and the ground area.

10. The method according to claim 7, characterized in that The determining of the target heat to be generated by the ground source heat pump module based on the total heat transfer of the enclosure structure, the cold air infiltration heat loss and the total heat transfer of the ground specifically includes: Determine the expected heat required for the greenhouse based on the total heat transfer of the enclosure structure, the cold air penetration heat loss, the total heat transfer of the ground, the structural additional coefficient and the wind additional coefficient; The target heat to be generated by the ground source heat pump module is determined based on the expected heat.

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