Waste heat recovery system for greenhouse

Abstract

The utility model discloses a waste heat recovery system for a greenhouse, which belongs to the field of waste heat recovery and comprises waste heat recovery equipment, the waste heat recovery equipment comprises an air-water heat exchange cavity, and two ends of the air-water heat exchange cavity are respectively connected with a heat collection cavity for collecting hot air and an exhaust cavity for exhausting heat-exchanged air. A first heat exchanger and a second heat exchanger which are connected in series are arranged in the gas-water heat exchange cavity, are respectively connected with the heat utilization end or the heat storage end through a water inlet pipe and a water outlet pipe, and are respectively arranged at the boundaries of the gas-water heat exchange cavity, the heat collection cavity and the exhaust cavity; a temperature sensor is arranged on the waste heat recovery equipment and used for sensing the temperature of air around the waste heat recovery equipment, and the temperature sensor transmits temperature signals to a controller for controlling water circulation in the first heat exchanger and the second heat exchanger. Heat in hot air is absorbed into the heat exchanger to exchange heat with liquid, waste heat generated by a greenhouse is utilized to the maximum extent, and energy waste is reduced.

Description

Technical Field

[0001] The utility model relates to the field of waste heat recovery, in particular to a waste heat recovery system for recovering heat from hot air, which is used in a greenhouse. Background Art

[0002] In northern my country, solar greenhouses are the main facilities for off-season wintering of fruits and vegetables. Although solar greenhouses can collect solar energy to store heat and release heat when the indoor temperature drops to ensure that the indoor temperature is not too low, when encountering extremely low temperatures, the temperature in the greenhouse is not enough to ensure the normal growth of crops, and heating equipment must be provided. However, traditional heating methods consume a lot of energy, which not only wastes energy but also greatly reduces greenhouse benefits.

[0003] In greenhouse cultivation, groundwater is usually used for crop irrigation, but the groundwater temperature is usually low. Changes in irrigation water temperature will trigger physiological reactions in crops. For example, low irrigation water temperature will reduce the dissolved oxygen content in the water, affecting the absorption and utilization of soil moisture and mineral nutrients by crop roots, and even affecting the normal growth of crop stems, leaves, and branches. In addition, the effective decomposition and transformation of soil mineral nutrients and the absorption and utilization of effective soil moisture are related to the concentration of soil solution, and the concentration of soil solution and soil temperature are closely related to the irrigation water temperature. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a waste heat recovery system for a greenhouse, which absorbs heat from hot air into a heat exchanger to exchange heat with liquid, thereby making maximum use of the waste heat generated by the greenhouse and reducing energy waste.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0006] A waste heat recovery system for a greenhouse includes a waste heat recovery device, which includes an air-water heat exchange chamber, wherein two ends of the air-water heat exchange chamber are respectively connected to a heat collection chamber for collecting hot air and an exhaust chamber for exhausting the heat-exchanged air, a first heat exchanger and a second heat exchanger connected in series are arranged in the air-water heat exchange chamber, the first heat exchanger and the second heat exchanger are respectively connected to a heat-using end or a heat storage end through a water inlet pipe and a water outlet pipe, the first heat exchanger and the second heat exchanger are respectively arranged at the boundary between the air-water heat exchange chamber and the heat collection chamber and the exhaust chamber, a temperature sensor is arranged on the waste heat recovery device for sensing the temperature of the air around the waste heat recovery device, and the temperature sensor transmits a temperature signal to a controller for controlling the water circulation in the first heat exchanger and the second heat exchanger.

[0007] A further improvement of the technical solution of the utility model is that a connecting conduit is arranged between the first heat exchanger and the second heat exchanger, the first heat exchanger is arranged on the side close to the heat collecting chamber, and a water inlet pipe is arranged at one end of the first heat exchanger, the second heat exchanger is arranged on the side close to the exhaust chamber, and a water outlet pipe is arranged at one end of the second heat exchanger.

[0008] A further improvement of the technical solution of the utility model is that a heating rod is arranged in the waste heat recovery device between the first heat exchanger and the second heat exchanger, and a room temperature sensor is arranged around the crops in the greenhouse. The room temperature sensor and the temperature sensor transmit signals to the controller. When the temperature sensed by the temperature sensor is higher than the set starting temperature of the heat exchanger, the heat exchanger of the air-water heat exchange chamber is started. When the temperature sensed by the room temperature sensor is lower than the starting temperature of the heating rod, the heating rod is started for auxiliary heating.

[0009] A further improvement of the technical solution of the utility model is that the heat collection chamber includes an arc-shaped air inlet channel, the heat collection chamber opening faces upward, and hot air enters the air-water heat exchange chamber from the heat collection chamber opening through the arc-shaped channel.

[0010] A further improvement of the technical solution of the utility model is that an air inlet for connecting to the air-water heat exchange chamber is arranged on one side of the exhaust chamber, and an exhaust port is arranged on the other side, the space of the exhaust chamber gradually decreases from the air inlet toward the exhaust port, and a fan is arranged in the exhaust chamber.

[0011] A further improvement of the technical solution of the utility model is that an exhaust connecting pipe is provided on the first heat exchanger and the second heat exchanger, the end of the exhaust connecting pipe is connected to the exhaust valve, and the exhaust valve outlet is arranged outside the bottom of the air-water heat exchange chamber.

[0012] Due to the adoption of the above technical solution, the technical progress achieved by the utility model is:

[0013] The utility model solves the problem that the temperature of the solar greenhouse is low in winter and needs to be supplemented by heating equipment. The waste heat recovery device collects the heat from the top of the greenhouse during the day, absorbs the heat into the heat exchanger to exchange heat with the liquid, and is used at the heat-using end or the heat storage end to maximize the use of the waste heat generated by the greenhouse and reduce energy waste. The specific form of heat application can be to store the collected heat underground, using the characteristics of the land to delay heat release. When the greenhouse temperature is low at night, the soil will release heat to keep the greenhouse temperature warm, increase the temperature of the greenhouse at night, increase the temperature of the soil and plant roots, and reduce frost damage in the solar greenhouse; it can also be used to connect with water and fertilizer integrated equipment to increase the temperature of water and fertilizer, adapt to crop growth, and enable the greenhouse to produce high value-added crops and achieve the effect of increasing production. Whether it is connected to the heat-using end or the heat storage end, the waste heat generated by the greenhouse is maximized to achieve sustainable development, reduce carbon emissions, and be more environmentally friendly and economical.

[0014] The system has a simple structure, and the two heat exchangers for waste heat recovery are respectively arranged on both sides of the air-water heat exchange chamber, and the heat exchange structure is reasonable. The exhaust pipe and exhaust valve are arranged to ensure smooth water circulation.

[0015] The temperature sensor and room temperature sensor are combined with the controller to make the waste heat recovery equipment and heating rod automatically open according to the temperature, which is more intelligent and practical. The heating rod serves as a backup heat source to provide protection for the crops in the greenhouse. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 It is a schematic diagram of the structure of the utility model;

[0018] Figure 2 It is a schematic diagram of the interior of the air-water heat exchange chamber;

[0019] Figure 3 This is a schematic diagram of the interior of the air-water heat exchange chamber from another angle;

[0020] Figure 4 is a schematic structural diagram of Embodiment 2;

[0021] Among them, 1. heat collecting chamber, 2. air-water heat exchange chamber, 3. exhaust chamber, 4. fan; 5. water inlet pipe, 6. water outlet pipe, 7. first heat exchanger; 8. second heat exchanger; 9. heating rod; 10. connecting duct; 11. exhaust valve, 12. equipment base. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below in conjunction with the embodiments:

[0023] Example 1

[0024] A waste heat recovery system for a greenhouse, such as Figure 1 , 2 As shown in Figure 3, the waste heat recovery device includes a heat collection chamber 1, an air-water heat exchange chamber 2 and an exhaust chamber 3. The air-water heat exchange chamber 2 is arranged between the heat collection chamber 1 and the exhaust chamber 3. The bottom of the air-water heat exchange chamber 2 is provided with a device base 12 for fixing the waste heat recovery device on the top of the greenhouse. The heat collection chamber 1 collects hot air; the air-water heat exchange chamber 2 has water flowing inside and air flowing outside, and the water is heated by the hot air; the exhaust chamber 3 guides the air after heat exchange through the fan and exhausts it.

[0025] The first heat exchanger 7 and the second heat exchanger 8 are arranged in the air-water heat exchange chamber 2, and a connecting conduit 10 is arranged between the first heat exchanger 7 and the second heat exchanger 8 to realize series connection. The first heat exchanger 7 and the second heat exchanger 8 are respectively arranged at the boundary between the air-water heat exchange chamber 2 and the heat collection chamber 1 and the exhaust chamber 3. Specifically, the first heat exchanger 7 is arranged on the side close to the heat collection chamber 1, and the water inlet pipe 5 is arranged on the upper end of the first heat exchanger 7, and the second heat exchanger 8 is arranged on the side close to the exhaust chamber 3, and the water outlet pipe 6 is arranged on the lower end of the second heat exchanger 8. The first heat exchanger 7 and the second heat exchanger 8 are respectively connected to the heat-using end or the heat storage end through the water inlet pipe 5 and the water outlet pipe 6. A temperature sensor is arranged on the waste heat recovery device to sense the temperature of the air around the waste heat recovery device. The temperature sensor transmits the temperature signal to the controller. When the temperature sensed by the temperature sensor is higher than the set start temperature of the heat exchanger, the heat exchanger of the air-water heat exchange chamber 2 is started to control the water circulation in the first heat exchanger 7 and the second heat exchanger 8.

[0026] The heat collecting chamber 1 includes an arc-shaped air inlet channel, and the opening of the heat collecting chamber 1 faces upward. Hot air enters the air-water heat exchange chamber 2 after passing through the arc-shaped channel from the opening of the heat collecting chamber 1. An air inlet for connecting to the air-water heat exchange chamber 2 is arranged on one side of the exhaust chamber 3, and an exhaust port is arranged on the other side. The space of the exhaust chamber 3 gradually decreases from the air inlet to the exhaust port, and the fan 4 is arranged at a position near the outlet of the exhaust chamber 3.

[0027] Preferably, the first heat exchanger 7 and the second heat exchanger 8 are provided with an exhaust connecting pipe, the end of the exhaust connecting pipe is connected to the exhaust valve 11, and the exhaust valve 11 outlet is arranged outside the bottom of the gas-water heat exchange chamber 2, which is used to discharge the gas in the water pipe to ensure that there are no bubbles in the pipeline and improve the heat exchange efficiency.

[0028] Among them, the waste heat recovery system of the utility model can have different applications, connected with the heat-using end or the heat storage end, to maximize the use of waste heat generated by the greenhouse and reduce energy waste. The specific form of heat application can be to store the collected heat underground. When the temperature of the greenhouse is low at night, the soil will release heat to keep the greenhouse temperature warm. It can also be used to connect with water and fertilizer integrated equipment to increase the temperature of water and fertilizer to adapt to crop growth, so that the greenhouse can produce high value-added crops and achieve the effect of increasing production. Whether it is connected to the heat-using end or the heat storage end, the waste heat generated by the greenhouse can be maximized to achieve sustainable development, reduce carbon emissions, and be more environmentally friendly and economical.

[0029] Example 2

[0030] The difference between this embodiment and embodiment 1 is that Figure 4As shown, a heating rod 9 is arranged in the waste heat recovery device between the first heat exchanger 7 and the second heat exchanger 8, and a room temperature sensor is arranged around the crops in the greenhouse. The room temperature sensor transmits a signal to a controller for controlling the start of the heating rod 9. When the temperature sensed by the room temperature sensor is lower than the start temperature of the heating rod, the electric heating rod is started to heat the air in the air-water heat exchange chamber to achieve a heating effect.

[0031] The embodiments described above are merely descriptions of preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A waste heat recovery system for a greenhouse, comprising a waste heat recovery device, characterized in that: The waste heat recovery device comprises an air-water heat exchange chamber (2), the two ends of the air-water heat exchange chamber (2) are respectively connected to a heat collection chamber (1) for collecting hot air and an exhaust chamber (3) for exhausting the heat exchanged air, a first heat exchanger (7) and a second heat exchanger (8) connected in series are arranged in the air-water heat exchange chamber (2), the first heat exchanger (7) and the second heat exchanger (8) are respectively connected to a heat-using end or a heat storage end through a water inlet pipe (5) and a water outlet pipe (6), the first heat exchanger (7) and the second heat exchanger (8) are respectively arranged at the boundary between the air-water heat exchange chamber (2) and the heat collection chamber (1) and the exhaust chamber (3), a temperature sensor is arranged on the waste heat recovery device for sensing the temperature of the air around the waste heat recovery device, and the temperature sensor transmits a temperature signal to a controller for controlling the water circulation in the first heat exchanger (7) and the second heat exchanger (8).

2. A waste heat recovery system for a greenhouse according to claim 1, characterized in that: A connecting conduit (10) is provided between the first heat exchanger (7) and the second heat exchanger (8); the first heat exchanger (7) is provided on a side close to the heat collecting chamber (1), and a water inlet pipe (5) is provided at one end of the first heat exchanger (7); the second heat exchanger (8) is provided on a side close to the exhaust chamber (3), and a water outlet pipe (6) is provided at one end of the second heat exchanger (8).

3. A waste heat recovery system for a greenhouse according to claim 1, characterized in that: A heating rod (9) is arranged in the waste heat recovery device between the first heat exchanger (7) and the second heat exchanger (8), and a room temperature sensor is arranged around the crops in the greenhouse. The room temperature sensor and the temperature sensor transmit signals to the controller. When the temperature sensed by the temperature sensor is higher than the set start temperature of the heat exchanger, the heat exchanger of the air-water heat exchange chamber (2) is started. When the temperature sensed by the room temperature sensor is lower than the start temperature of the heating rod, the heating rod (9) is started for auxiliary heating.

4. A waste heat recovery system for a greenhouse according to claim 1, characterized in that: The heat collection chamber (1) comprises an arc-shaped air inlet passage. The opening of the heat collection chamber (1) faces upward. Hot air enters the heat collection chamber (1) from the opening and passes through the arc-shaped passage before entering the air-water heat exchange chamber (2).

5. A waste heat recovery system for a greenhouse according to claim 1, characterized in that: The exhaust chamber (3) is provided with an air inlet on one side for connecting to the air-water heat exchange chamber (2), and an exhaust port on the other side. The space of the exhaust chamber (3) gradually decreases from the air inlet toward the exhaust port. A fan (4) is provided in the exhaust chamber (3).

6. A waste heat recovery system for a greenhouse according to claim 1, characterized in that: The first heat exchanger (7) and the second heat exchanger (8) are provided with exhaust connecting pipes, the ends of which are connected to exhaust valves (11), and the exhaust valve (11) has an outlet arranged outside the bottom of the air-water heat exchange chamber (2).

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