Solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain producing area drying and storing system

Abstract

The invention discloses a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, and particularly relates to the technical field of agricultural engineering and new energy, and the drying and storage system adopts the combination of a solar heat collection and storage system, an air source heat pump system, a temperature control heat exchange system, a multifunctional drying and storage integrated bin and a control decision system. According to the solar heat collection and storage system, multiple sets of vacuum tube solar heat collectors are connected in series and installed in an open space without shielding, and the installation dip angle is the local dimension; the solar heat collection and storage system adopts a staged heat storage water tank, so that the water temperature can quickly reach the working temperature during emergency drying and storage; an electromagnetic valve and a circulating water pump are installed between the vacuum tube solar heat collector and the grading type heat storage water tank, stable heat storage is guaranteed, and temperature probes are installed in a water inlet and a water outlet of the vacuum tube solar heat collector and the grading type heat storage water tank to collect temperature signals.

Description

Technical Field

[0001] The present invention relates to the field of agricultural engineering and new energy technology, and in particular to a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production site drying and storage system. Background Art

[0002] With the continuous improvement of the level of grain mechanization, the grain harvest period is shortened, resulting in a large amount of grain accumulation in a short period of time. It cannot be dried in time, which leads to grain mildew and germination, causing certain losses. This kind of food waste will also lead to the loss of arable land and water resources. In addition, the wasted food will emit greenhouse gases such as carbon dioxide during waste treatment. Therefore, an advanced grain drying and storage technology is urgently needed to cope with the short-term accumulation problem after grain harvest, reduce grain losses, save energy and protect the environment. Against this background, grain production site drying and storage technology has gradually received attention. Grain production site drying and storage technology refers to a series of technical measures for drying and storage processing at the grain production site. Its purpose is to scientifically process grain at the source to reduce the loss of grain during storage and transportation and improve the quality of grain.

[0003] At present, there are few studies on grain production area drying and storage technology. For example, the Chinese patent application number 201610521315.X discloses a grain drying, storage and conditioning integrated warehouse with built-in bellows and external interlayers. By arranging several layers of inner bellows in the middle of the integrated warehouse, outer interlayers are arranged around the integrated warehouse, and heating devices, refrigeration devices and humidification devices are arranged outside the integrated warehouse, the functions of heating and drying, refrigeration and cooling, humidification and conditioning are realized; the Chinese patent application number 201720676073.1 discloses an intelligent grain drying and storage integrated equipment, which realizes simple intelligent grain drying and storage operations by setting a single-chip microcomputer to automatically control the circuit; the Chinese patent application number 202010910292.8 discloses a fully automatic grain drying and storage integrated equipment, which realizes grain drying and storage operations by fixing a heating wire between the storage barrel and the inner cylinder and setting a threaded rod in the middle of the inner cylinder to turn the grain. The two are combined to realize grain drying and storage operations.

[0004] The above-mentioned research on grain production site drying and storage technology has the following problems: ① The drying heat source still uses traditional electricity, which has high energy consumption and operating costs and poor environmental protection; ② Lack of intelligence, it is difficult to realize intelligent drying and storage through autonomous perception and control decisions based on actual environmental parameters and drying requirements; ③ Insufficient grain quality monitoring capabilities, it is difficult to monitor grain moisture, temperature and other quality indicators in real time, and dynamically adjust drying parameters according to the monitoring results. Summary of the invention

[0005] To this end, the present invention provides a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production site drying and storage system to solve the problems raised in the background technology.

[0006] In order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, which adopts a solar energy heat collection and storage system, an air source heat pump system, a temperature control and heat exchange system, a multifunctional drying and storage integrated warehouse and a control decision system.

[0007] Preferably, the solar heat collection and storage system uses multiple groups of vacuum tube solar collectors installed in series in an open and unobstructed space, and the installation angle is the local dimension; the solar heat collection and storage system uses a graded water storage tank, which is convenient for the water temperature to quickly reach the working temperature during emergency drying and storage; a solenoid valve and a circulating water pump are installed between the vacuum tube solar collector and the graded water storage tank to ensure stable heat storage, and temperature probes are installed in the water inlet and outlet of the vacuum tube solar collector and the graded water storage tank to collect temperature signals.

[0008] Preferably, the temperature control and heat exchange system includes a temperature control water tank, a tube-fin air heater, a plate heat exchanger, a PPR pipe, a solenoid valve, a circulating water pump and a temperature monitor. The temperature control water tank is provided with hot water by the solar heat storage system and the air source heat pump system to maintain the water temperature. The tube-fin air heater is connected to the temperature control water tank through a PPR pipe, and the tube-fin air heater is connected to the centrifugal fan through a PVC pipe. The centrifugal fan exchanges the heat of the hot air for the grain in the drying and storage integrated warehouse for grain drying.

[0009] Preferably, the plate heat exchanger is connected in series with the evaporator of the air source heat pump, and the plate heat exchanger is connected to the hot water storage tank. The waste heat of the hot water storage tank is used to replenish the air source heat pump, thereby solving the problem of reduced heat exchange efficiency caused by frosting of the evaporator of the air source heat pump under low temperature conditions.

[0010] Preferably, the multifunctional integrated drying and storage warehouse adopts a square overhead silo, and the silo wall is made of galvanized steel plate, which is connected by riveting, assembly and welding; a funnel is installed under the silo, the funnel cone angle is 50°, and the funnel outlet is 0.5m from the ground; an annular air duct is set on the funnel silo wall and bottom to connect the warehouse and the fan, which is used for mechanical ventilation operation after the grain enters the warehouse.

[0011] Preferably, the control decision system includes a valve and water pump control system for controlling and switching various modes, a collection system for monitoring baking and storage process parameters, a control system for achieving a constant air temperature baking and storage process, and a main controller for determining the working mode and integrating various systems.

[0012] Preferably, the valve and water pump control system includes a controller and a first valve, a second valve, a third valve, a fourth valve, a fifth valve, a sixth valve, a seventh valve, a first circulation pump, a second circulation pump, a third circulation pump and a fourth circulation pump connected to the controller, the first valve is arranged on the main line connecting the solar collector to the tap water, the second valve and the third valve are arranged on two branches connecting the solar collector to the graded water storage tank, the fourth valve, the fifth valve and the sixth valve are arranged on three branches connecting the temperature-controlled water tank to the graded water storage tank and the air source heat pump, and the seventh valve is arranged on the main line connecting the plate heat exchanger to the water storage tank.

[0013] Preferably, the collection system is connected to the input end of the controller; the collection system includes a first temperature sensor arranged at the inlet of the solar collector, a second temperature sensor arranged at the outlet of the solar collector, a third and fourth temperature sensors arranged in the graded heat storage tank, a fifth temperature sensor arranged in the temperature-controlled water tank, a sixth temperature sensor arranged in the heat pump condenser, a seventh temperature sensor arranged at the air inlet of the drying and storage bin, the first, second and third water level sensors arranged in the heat storage tank and the temperature-controlled water tank, a wind speed sensor arranged at the air inlet of the drying and storage bin, an integrated grain moisture temperature sensor arranged in the drying and storage bin, and a weather station for monitoring external environmental parameters.

[0014] Preferably, the control system of the constant air temperature drying and storage process includes a controller and a fan frequency converter connected to the controller. The frequency converter changes the ventilation volume of the centrifugal fan according to the outside air temperature collected by the meteorological station, and cooperates with the tube-fin air heater to achieve constant air temperature during the drying and storage operation.

[0015] The present invention has the following advantages:

[0016] (1) Higher energy saving. The solar energy-heat pump dual-core low-carbon intelligent coupled complementary grain production area drying and storage system of the present invention is mainly powered by solar energy and supplemented by heat pump energy. By switching between multiple energy supply modes, it can continuously and stably complete the drying and storage operations under different weather conditions, with low operating costs and significant energy-saving effects.

[0017] (2) Higher intelligence: The food production area drying and storage system powered by solar energy coupled heat pump of the present invention coordinates and controls each system to independently complete the drying and storage operation through the control decision system, thus saving manpower and material resources.

[0018] (3) Stronger real-time performance. The grain production site drying and storage system powered by solar energy coupled heat pump of the present invention can monitor the grain quality in real time during the drying and storage process, and can dynamically adjust the drying and storage process parameters according to the monitoring results. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the solar energy-heat pump dual-core low-carbon intelligent coupling and complementary grain production site drying and storage system provided by the present invention.

[0020] In the figure: 1. First electromagnetic valve; 2. First temperature sensor; 3. Solar collector; 4. Second temperature sensor; 5. Second electromagnetic valve; 6. Third electromagnetic valve; 7. Heat collector circulation pump; 8. First water level sensor; 9. Third temperature sensor; 10. Fourth electromagnetic valve; 11. Small hot water storage tank; 12. Second water level sensor; 13. Fourth temperature sensor; 14. Fifth electromagnetic valve; 15. Large hot water storage tank; 16. Drain port; 17. Plate heat exchanger; 18. Seventh electromagnetic valve; 19. Supplement 1. Circulating water pump; 20. Compressor; 21. Condenser; 22. Expansion valve; 23. Evaporator; 24. Temperature-controlled circulating water pump; 25. Third water level sensor; 26. Fifth temperature sensor; 27. Temperature-controlled water tank; 28. Air heating circulating water pump; 29. ​​Tube-fin air heater; 30. Centrifugal fan; 31. Wind speed sensor; 32. Grain moisture and temperature integrated sensor; 33. Multifunctional drying and storage integrated bin; 34. Sixth solenoid valve; 35. Sixth temperature sensor; 36. Frequency converter; 37. Seventh temperature sensor. DETAILED DESCRIPTION

[0021] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] This embodiment provides a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production site drying and storage system.

[0023] As attached Figure 1 As shown, the grain production site drying and storage system powered by a solar energy coupled heat pump of the present invention includes a solar energy heat collection and storage system, an air source heat pump system, a temperature control and heat exchange system, a multifunctional drying and storage integrated warehouse, and a control decision system.

[0024] First, multiple groups of solar collectors 3 are connected in series and installed facing south in an open and unobstructed space, with the installation angle being the local latitude; the outlet of the collector 3 is connected to a small heat storage tank 11 and a large heat storage tank 15, and a second solenoid valve 5 and a third solenoid valve 6 are installed on the two branches respectively, and the two branches are connected by a three-way pipe; the inlet of the collector 3 is connected to the lower part of the graded heat storage tank and a heat collection circulation water pump 7 is installed in the middle, and the inlet of the collector 3 is also connected to a tap water pipe and a first solenoid valve 1 is installed in the middle, which is only used to provide water to the graded heat storage tank and the collector 3 before the system is operated. When the system is running, the first solenoid valve 1 is in a normally closed state; the first temperature sensor 2 and the second temperature sensor 4 respectively monitor the inlet and outlet temperatures of the collector, and control the start and stop of the heat collection circulation water pump 7 by the temperature difference.

[0025] Then, the water temperature changes of the small hot water storage tank 11 and the large hot water storage tank 15 are monitored respectively through the third temperature sensor 9 and the fourth temperature sensor 13, and the water temperature changes of the temperature control water tank 27 are monitored through the fifth temperature sensor 26, and the operation of the temperature control energy supply system is adjusted and selected; the external temperature changes are monitored through the meteorological station, and the start and stop of the energy replenishment circulation water pump 19 are controlled.

[0026] Finally, the temperature-controlled water tank 27 is connected to the tube-fin air heater 29 and an air heating circulating water pump 28 is installed in the middle. The natural air is heated to the drying temperature by the tube-fin air heater 29 and continuously blown into the multifunctional drying and storage integrated warehouse 33 by the centrifugal fan 30. The wind speed sensor 31 and the seventh temperature sensor 37 monitor the wind speed and wind temperature at the ventilation inlet of the drying and storage warehouse, and the grain moisture temperature integrated sensor 32 monitors the change of grain quality in the drying and storage warehouse. The collected data is fed back to the main controller, and the main controller controls the speed of the centrifugal fan through the inverter 36. At this point, the grain production area drying and storage integrated system with solar energy-heat pump dual-core low-carbon intelligent coupling complementary energy supply proposed in this embodiment is completed.

[0027] Specifically, the entire system hardware and software are installed in advance during the grain harvest season, and the solar energy heat storage system performs energy storage work one week before the grain harvest. The collector 3 absorbs solar energy to heat the water in the small heat storage tank 11 and the large heat storage tank 15, and circulates the water through the heat collection circulation water pump 7 of the heat collection and storage system.

[0028] Specifically, in the summer grain harvest season, when the ambient temperature is stable and not lower than 20°C and the temperature difference between day and night is small, natural air ventilation is used when the temperature is high during the day, and the solar energy heat storage system converts solar energy into heat energy and stores it in hot water for use at night; during the natural ventilation operation, the collection system collects grain quality data (mainly grain moisture) in the drying and storage bin every 5 minutes, and the main controller dynamically adjusts the speed of the centrifugal fan through feedback data, thereby realizing variable frequency ventilation and significantly saving energy. When the ambient temperature at night drops below the drying and storage temperature, the temperature control circulating water pump 24 and the air heating circulating water pump 28 are turned on, and the small hot water storage tank 11 and the large hot water storage tank 15 are used to supply energy to stabilize the water temperature of the temperature control water tank 27 at the working temperature, and the heat is transferred to the natural air through the tube-fin air heater 29 for heating and drying.

[0029] Specifically, in the autumn and winter grain harvest season, when the ambient temperature is low and the temperature difference between day and night is large, according to the solar radiation intensity, when the radiation is strong during the day, the ambient temperature is not lower than 5°C, and the water temperature of the hot water storage tank is not lower than the working temperature, the small hot water storage tank 11 is driven to supply energy first, and the solar collector stores energy for the large hot water storage tank 15 at the same time; when it is detected that the water temperature of the small hot water storage tank 11 is lower than the working temperature, the main controller independently decides to control the electromagnetic valve and the water pump control system to switch the energy supply equipment and drive the large hot water storage tank 15 to supply energy. When the temperature drops at night and the water temperature of the graded hot water storage tanks is lower than the working temperature, the air source heat pump system is turned on to drive the compressor 20 to work, and the heat is transferred to the temperature control water tank 27 through the condenser 21 to stabilize its water temperature at the working temperature.

[0030] Specifically, on consecutive cloudy days, when solar radiation is weak during the day and the temperature of the hot water storage tank is lower than the working temperature, the air source heat pump system is used to supply energy to drive the compressor 20 to maintain the water temperature of the temperature-controlled water tank at the working temperature, thereby achieving constant temperature drying and storage operation.

[0031] Furthermore, in rainy and snowy weather, when the ambient temperature is lower than 5°C, the air source heat pump system cannot operate stably and frost will appear on the evaporator 23, which greatly reduces the heat exchange efficiency of the evaporator. At this time, while maintaining the normal operation of the air source heat pump system, the energy replenishment circulation water pump 19 and the seventh electromagnetic valve 18 are turned on to replenish the air source heat pump system with the waste heat of the large hot water storage tank 15. The heat pump working fluid is first heated in the plate heat exchanger 17 before entering the evaporator 23, thereby increasing the heat of the working fluid and the heat exchange efficiency, solving the problem of attenuation and low performance of the heating performance of the air source heat pump under low temperature conditions.

[0032] The comparison of energy consumption, intelligent control degree, grain quality after drying and storage, and economic benefits between this embodiment and the traditional drying and storage method is shown in Table 1. The traditional drying and storage method refers to the Chinese patent with patent application number 201610521315.X, which adopts a grain drying, storage and conditioning integrated warehouse with built-in bellows and external interlayers.

[0033] Table 1

[0034]

[0035] As can be seen from Table 1, this embodiment is superior to the traditional baking and storage method in many aspects. The energy consumption of this embodiment is 8kWh / ton, which is significantly lower than the 14kWh / ton of the traditional method, and the energy saving effect reaches about 43%. This is mainly due to the efficient combination of solar energy and heat pumps, which reduces dependence on traditional energy. At the same time, this embodiment performs better in terms of grain loss rate, color score and nutrient retention rate. The loss rate is only 1.5%, which is significantly lower than the 3.0% of the traditional method; the color score is 8.5, which is higher than the 7 of the traditional method; the nutrient retention rate reaches 95%, which is significantly better than the 88% of the traditional method. In addition, in terms of economic benefits, the annual operating cost has dropped from 50,000 yuan to 30,000 yuan.

[0036] In summary, this embodiment is not only significantly superior to the traditional drying and storage method in terms of energy saving and grain quality retention, but also shows strong advantages in economic benefits, providing a more reliable and efficient solution for grain drying and storage.

[0037] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A solar-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The drying and storage system combines a solar energy heat collection and storage system, an air source heat pump system, a temperature control and heat exchange system, a multifunctional drying and storage integrated warehouse and a control decision system.

2. According to claim 1, a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The solar heat collection and storage system adopts multiple groups of vacuum tube solar collectors installed in series in an open and unobstructed space, and the installation inclination angle is the local dimension; the solar heat collection and storage system adopts a graded heat storage tank; a solenoid valve and a circulating water pump are installed between the vacuum tube solar collector and the graded heat storage tank, and temperature probes are installed in the water inlet and outlet of the vacuum tube solar collector and the graded heat storage tank to collect temperature signals.

3. According to claim 1, a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The temperature control and heat exchange system includes a temperature control water tank, a tube-fin air heater, a plate heat exchanger, a PPR pipe, a solenoid valve, a circulating water pump and a temperature monitor. The temperature control water tank is provided with hot water by the solar heat storage system and the air source heat pump system to maintain the water temperature. The tube-fin air heater is connected to the temperature control water tank through a PPR pipe, and the tube-fin air heater is connected to the centrifugal fan through a PVC pipe.

4. According to claim 3, a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The plate heat exchanger is connected in series with the evaporator of the air source heat pump, and the plate heat exchanger is connected to the hot water storage tank. The waste heat of the hot water storage tank is used to replenish the air source heat pump, thereby solving the problem of reduced heat exchange efficiency caused by frosting of the evaporator of the air source heat pump under low temperature conditions.

5. According to claim 1, a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The multifunctional drying and storage integrated warehouse adopts a square overhead silo, and the silo wall is made of galvanized steel plate, which is connected by riveting, assembly and welding. A funnel is installed under the silo, the funnel cone angle is 50°, and the funnel outlet is 0.5m from the ground. An annular air duct is set on the funnel silo wall and bottom to connect the warehouse and the fan, which is used for mechanical ventilation operations after the grain enters the warehouse.

6. According to claim 1, a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The control decision system includes a valve and water pump control system for controlling and switching various modes, a collection system for monitoring baking and storage process parameters, a control system for achieving a constant air temperature baking and storage process, and a main controller for determining the working mode and integrating various systems.

7. According to claim 6, a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The valve and water pump control system includes a controller and a first valve, a second valve, a third valve, a fourth valve, a fifth valve, a sixth valve, a seventh valve, a first circulation pump, a second circulation pump, a third circulation pump and a fourth circulation pump connected to the controller, the first valve is arranged on the main road connecting the solar collector to the tap water, the second valve and the third valve are arranged on two branches connecting the solar collector to the graded hot water storage tank, the fourth valve, the fifth valve and the sixth valve are arranged on three branches connecting the temperature-controlled water tank to the graded hot water storage tank and the air source heat pump, and the seventh valve is arranged on the main road connecting the plate heat exchanger to the hot water storage tank.

8. According to claim 6, a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The collection system is connected to the input end of the controller; the collection system includes a first temperature sensor arranged at the inlet of the solar collector, a second temperature sensor arranged at the outlet of the solar collector, a third and fourth temperature sensors arranged in the graded hot water storage tank, a fifth temperature sensor arranged in the temperature-controlled water tank, a sixth temperature sensor arranged in the heat pump condenser, a seventh temperature sensor arranged at the air inlet of the drying and storage bin, the first, second and third water level sensors arranged in the hot water storage tank and the temperature-controlled water tank, a wind speed sensor arranged at the air inlet of the drying and storage bin, an integrated grain moisture and temperature sensor arranged in the drying and storage bin, and a meteorological station for monitoring external environmental parameters.

9. According to claim 6, a solar energy-heat pump dual-core low-carbon intelligent coupling complementary grain production area drying and storage system, Features: The control system of the constant air temperature drying and storage process includes a controller and a fan frequency converter connected to the controller. The frequency converter changes the ventilation volume of the centrifugal fan according to the outside air temperature collected by the meteorological station, and cooperates with the tube-fin air heater to achieve constant air temperature during the drying and storage operation.

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