System and method for implementing circulation cold supplementing and cooling on grain depot by using natural cold source

Abstract

The invention discloses a system and a method for implementing circulation cold supplementing and cooling on a grain depot by using a natural cold source, relates to the technical field of grain and oil storage, and aims to maintain a low-temperature environment of the grain depot on the premise of avoiding water loss of grains. According to the main technical scheme, the system for implementing circulation cold supplementing and cooling on the grain depot through the natural cold source comprises the grain depot and a refrigeration part; a plurality of groups of heat exchange pipes are arranged in the grain depot; the refrigerating part comprises a cooling tower, a liquid storage tank and a conveying pump, an outlet of the cooling tower, the liquid storage tank, the conveying pump and the lower end of the heat exchange pipe are sequentially connected, and the upper end of the heat exchange pipe is connected to an inlet of the cooling tower.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of grain storage, and in particular to a system and method for implementing circulating cooling of a grain depot by using a natural cold source. BACKGROUND

[0002] Low-temperature grain storage is one of the currently recognized economic, practical and effective green grain storage technologies. Through low-temperature grain storage technology, the grain pile temperature can be controlled within a certain range, which can maximize the protection of food security and obtain the maximum economic benefit.

[0003] Xinjiang has the advantages of long winter and natural low temperature. Winter low temperature is a key natural resource for the "cold core grain pile" technology, and is particularly suitable for the promotion and use of the "cold core grain pile" low-temperature grain storage technology.

[0004] According to the investigation, the current "cold core grain pile" technology of grain storage enterprises mainly exchanges heat between the inside and outside of the grain depot through ventilation equipment in winter to cool the grain pile. After cooling, the grain depot is sealed and insulated to ensure that the grain pile remains at a low temperature to safely pass through the hot summer. However, due to the high-power ventilation device in winter, the actual process is a "drying" process of the grain, resulting in a large loss of grain moisture (3%-5%), which is much higher than the national standard of 2% or less. For a grain depot with a storage capacity of tens of thousands of tons, the economic loss is undoubtedly huge. SUMMARY

[0005] Therefore, the present application provides a system and method for implementing circulating cooling of a grain depot by using a natural cold source, mainly to maintain a low-temperature environment in the grain depot while avoiding loss of grain moisture.

[0006] To achieve the above-mentioned purpose, the present application mainly provides the following technical solutions:

[0007] In one aspect, the present application provides a system for implementing circulating cooling of a grain depot by using a natural cold source, which comprises a grain depot and a refrigeration part.

[0008] The grain depot is provided with a plurality of heat exchange pipes.

[0009] The refrigeration part comprises a cooling tower, a liquid storage tank and a delivery pump. The outlet of the cooling tower, the liquid storage tank, the delivery pump and the lower end of the heat exchange pipe are connected in sequence, and the upper end of the heat exchange pipe is connected to the inlet of the cooling tower.

[0010] The purpose of the present application and the technical problems thereof can be further achieved by the following technical measures.

[0011] Optionally, the refrigeration part further comprises a distribution box, a vacuum pump, a finned tube radiator and a condenser box, the distribution box, the condenser box and the liquid storage tank are arranged in sequence from high to low, the outlet of the cooling tower is connected to one end of the top wall of the distribution box through a first pipeline, the other end of the top wall of the distribution box is connected to the inlet of the vacuum pump, the outlet of the vacuum pump is connected to one end of the heat exchange column of the finned tube radiator, the other end of the heat exchange column of the finned tube radiator is connected to the upper end of the first side wall of the condenser box, the upper end of the second side wall of the condenser box is connected to the top wall of the liquid storage tank, and the bottom wall of the distribution box is connected to the lower end side of the liquid storage tank.

[0012] Optionally, the bottom wall of the distribution box is connected to the lower end side of the liquid storage tank through a U-shaped tube.

[0013] Optionally, a second pipeline is further included, one end of the second pipeline is connected to the upper end of the other side wall of the condenser box, and the other end of the second pipeline is connected to the top wall of the liquid storage tank, and the second pipeline is provided with a check valve.

[0014] Optionally, a pressure relief valve and a baffle are further included, the baffle is arranged between the first side wall and the second side wall, a gap is arranged between the lower end of the baffle and the bottom wall of the condenser box, and the top wall of the condenser box between the first side wall and the baffle is connected to the pressure relief valve.

[0015] Optionally, a plurality of groups of the heat exchange pipe matrix are arranged in the grain depot.

[0016] Optionally, a plurality of temperature sensors are further included, the plurality of temperature sensors are uniformly arranged on the inner side wall of the grain depot, the temperature sensors are electrically connected to the input end of the controller, and the output end of the controller is electrically connected to the conveying pump.

[0017] Optionally, a first liquid discharge pipe is further included, one end of the first liquid discharge pipe is connected to the lower end side of the liquid storage tank, and the other end of the first liquid discharge pipe is connected to a first liquid discharge valve.

[0018] Optionally, a second liquid discharge pipe is further included, one end of the second liquid discharge pipe is connected to the lower end side of the condenser box, and the other end of the second liquid discharge pipe is connected to a second liquid discharge valve.

[0019] In another aspect, the application provides a method for implementing circulating cooling of a grain depot by using a natural cold source, which uses the system for implementing circulating cooling of a grain depot by using a natural cold source, and the method comprises the following steps:

[0020] Step one: inputting a preset temperature value of the grain depot through the display screen of the controller to make the controller store an electric level value representing the preset temperature;

[0021] Step two: simultaneously starting the conveying pump and the fan of the cooling tower;

[0022] Step three, the temperature sensor transmits the electric signal representing the real-time temperature of the grain depot to the controller, when the electric signal is less than the electric level, the controller sends the instruction to the frequency converter of the conveying pump motor to reduce the rotating speed of the conveying pump motor, and through the integral feedback control mode, the temperature of the grain depot is stabilized at the preset temperature.

[0023] By the above technical solution, the application has at least the following advantages:

[0024] The refrigerant liquid cooled by the cooling tower flows through the heat exchange pipe from bottom to top, takes away the heat of the grain in the grain depot, the heat transfer between the refrigerant and the grain is not mass transfer, there is no air convection between the grain and the external environment, and the moisture in the grain is not lost, which ensures the grain quality and maintains the low-temperature environment of the grain depot. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 A structure schematic diagram of a system for implementing the circulation cooling of the grain depot by using the natural cold source is provided for the embodiment of the application.

[0026] Figure 2 For Figure 1 An enlarged view of part A.

[0027] The reference signs in the drawings of the specification include: grain depot 1, heat exchange pipe 2, cooling tower 3, liquid storage tank 4, conveying pump 5, flow dividing tank 6, vacuum pump 7, finned tube radiator 8, condensing tank 9, first pipeline 10, U-shaped pipe 11, second pipeline 12, check valve 13, pressure relief valve 14, baffle 15, temperature sensor 16. DETAILED DESCRIPTION

[0028] To further explain the technical means and effects adopted by the application to achieve the predetermined application purpose, the specific implementation, structure, features and effects according to the application are described in detail as follows by combining with the drawings and preferred embodiments. In the following description, different “an embodiment” or “embodiments” do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0029] The application will be further described in detail below by combining with the drawings and embodiments.

[0030] As Figure 1 shown, in one aspect, an embodiment of the application provides a system for implementing the circulation cooling of the grain depot by using the natural cold source, which comprises: a grain depot 1 and a refrigeration part.

[0031] The grain depot 1 is provided with a plurality of groups of heat exchange pipes 2.

[0032] The refrigeration unit includes a cooling tower 3, a liquid storage tank 4, and a delivery pump 5. The outlet of the cooling tower 3, the liquid storage tank 4, the delivery pump 5, and the lower end of the heat exchange tube 2 are connected in sequence, and the upper end of the heat exchange tube 2 is connected to the inlet of the cooling tower 3.

[0033] The working process of a system that uses natural cold sources to implement circulating cooling and temperature reduction in grain depots is as follows:

[0034] Cooling tower 3, liquid storage tank 4, transfer pump 5, and heat exchange pipe 2 are connected in sequence to form a circulation path for the refrigerant liquid, which removes the heat from the grain in grain depot 1.

[0035] Specifically, the refrigerant liquid used is antifreeze, ethylene glycol, or a salt solution.

[0036] like Figure 1 and Figure 2 As shown, in a specific embodiment, the refrigeration unit further includes a distribution box 6, a vacuum pump 7, a finned tube radiator 8, and a condenser 9. The positions of the distribution box 6, the condenser 9, and the liquid storage tank 4 are sequentially lower. The outlet of the cooling tower 3 is connected to one end of the top wall of the distribution box 6 through a first pipe 10. The other end of the top wall of the distribution box 6 is connected to the inlet of the vacuum pump 7. The outlet of the vacuum pump 7 is connected to one end of the heat exchange tubes of the finned tube radiator 8. The other end of the heat exchange tubes of the finned tube radiator 8 is connected to the upper end of the first side wall of the condenser 9. The upper end of the second side wall of the condenser 9 is connected to the top wall of the liquid storage tank 4. The bottom wall of the distribution box 6 is connected to the lower end of the liquid storage tank 4.

[0037] In this embodiment, specifically, the refrigerant liquid, after being initially cooled by the cooling tower 3, reaches the distribution box 6 through the first pipe 10. Some of the refrigerant liquid in the distribution box 6 settles into the storage tank 4. At the same time, due to the vacuum pump 7 drawing gas from the distribution box 6, the partial pressure of the gas phase in the distribution box 6 is reduced to below the saturated vapor pressure, which accelerates the evaporation of the refrigerant liquid in the distribution box 6. The evaporated refrigerant gas reaches the finned tube radiator 8 through the vacuum pump 7, is cooled and condensed again, and flows to the condensation box 9. The refrigerant liquid in the condensation box 9 overflows into the storage tank 4. The refrigerant liquid in the storage tank 4 is pumped to the heat exchange tube 2 in the grain depot 1.

[0038] Specifically, after the refrigerant liquid is depressurized and evaporated, it is cooled and condensed by the finned tube radiator 8, releasing the latent heat of vaporization, which further reduces the temperature of the refrigerant liquid and helps to increase the cooling speed of the grain in the grain depot 1.

[0039] Specifically, the positions of the distribution box 6, the condenser box 9, and the liquid storage tank 4 are successively lower. Although the air pressure in the distribution box 6 is reduced due to the suction effect of the vacuum pump 7, the position of the distribution box 6 is six meters higher than that of the liquid storage tank 4. Therefore, the refrigerant in the distribution box 6 can flow from top to bottom to the liquid storage tank 4.

[0040] Specifically, vacuum pump 7 is a water ring vacuum pump and also includes a steam-water separator. The outlet pipe of the water ring vacuum pump is connected to the tangential inlet of the steam-water separator, and the upper outlet of the steam-water separator is connected to one end of the heat exchange tube of the finned tube radiator 8.

[0041] Specifically, the finned tube radiator 8 includes a fan, a finned assembly, and a bent heat exchange tube. The heat exchange tube runs through the finned assembly, and the fan is located on the outside of the finned assembly to accelerate the airflow speed on the fin surface.

[0042] In a specific embodiment, the bottom wall of the diversion box 6 is connected to the lower end of the liquid storage tank 4 via a U-shaped tube 11.

[0043] In this embodiment, specifically, the refrigerant liquid is temporarily stored in the U-shaped tube 11, forming a liquid seal between the distribution box 6 and the storage tank 4.

[0044] In a specific embodiment, a second pipe 12 is also included. One end of the second pipe 12 is connected to the upper end of the other side wall of the condenser 9, and the other end is connected to the top wall of the liquid storage tank 4. A check valve 13 is installed on the second pipe 12.

[0045] In this embodiment, specifically, by installing a check valve 13, the refrigerant liquid is prevented from flowing back into the condenser box 9 when the liquid storage tank 4 is full.

[0046] In a specific embodiment, it also includes a pressure relief valve 14 and a baffle 15. The baffle 15 is disposed between the first side wall and the second side wall. There is a gap between the lower end of the baffle 15 and the bottom wall of the condenser 9. The top wall of the condenser 9 between the first side wall and the baffle 15 is connected to the pressure relief valve 14.

[0047] In this embodiment, specifically, the refrigerant liquid condensed by the finned tube radiator 8 enters the condenser box 9. The refrigerant liquid can only reach the outlet of the condenser box 9 after passing through the gap at the lower end of the baffle 15. The gas phase space of the condenser box 9 on both sides of the baffle 15 is isolated to prevent the gas pressure change on the inlet side of the condenser box 9 from causing the gas pressure in the liquid storage tank 4 to fluctuate.

[0048] When the refrigerant is condensed by the finned tube radiator 8, but is not completely liquefied and the proportion of gaseous components is still relatively large, the gas pressure on the inlet side of the condenser box 9 is too high. The high-pressure gas causes the pressure relief valve 14 to open, releasing the gas pressure in the condenser box 9 and ensuring the safe operation of the equipment.

[0049] In a specific embodiment, multiple sets of the heat exchange tubes 2 are arranged in a matrix within the grain depot 1.

[0050] In this embodiment, specifically, multiple sets of heat exchange tubes 2 are arranged in a matrix inside the grain depot 1 to facilitate synchronous cooling of grain in different areas of the grain depot 1.

[0051] Specifically, heat exchange tube 2 adopts an S-shaped bend.

[0052] In a specific embodiment, a plurality of temperature sensors 16 are also included. The plurality of temperature sensors 16 are evenly distributed on the inner side wall of the grain depot 1. The temperature sensors 16 are electrically connected to the input terminal of the controller, and the output terminal of the controller is electrically connected to the conveying pump 5.

[0053] In this embodiment, multiple temperature sensors 16 are evenly distributed on the inner wall of the grain storage 1. The temperature sensors 16 and the upper end of the heat exchange tube 2 are at the same height. When the grain buries the heat exchange tube 2 and the grain storage 1 is full, the temperature sensors 16 will not be buried. This makes it easier for the temperature sensors 16 to obtain the temperature value of the grain surface. Because the temperature of the surface grain is higher than that of the lower grain due to the circulation of the refrigerant liquid, the temperature of the surface grain monitored by the temperature sensors 16 is more representative.

[0054] In a specific embodiment, it also includes a first drain pipe, one end of which is connected to the lower end of the liquid storage tank 4, and the other end of which is connected to a first drain valve.

[0055] In this embodiment, specifically, when the system has been running for a long time and needs cleaning, the first drain valve is opened to drain the liquid in the storage tank 4. A manhole is installed on the top wall of the storage tank 4 to facilitate the filling of new refrigerant liquid into the storage tank 4.

[0056] In a specific embodiment, a second drain pipe is also included, one end of which is connected to the lower end of the condenser 9, and the other end of which is connected to a second drain valve.

[0057] In this embodiment, specifically, when the system has been running for a long time and the refrigerant liquid needs to be replaced, the second drain valve can be opened first to drain the refrigerant liquid in the condenser box 9.

[0058] On the other hand, another embodiment of the present invention provides a method for implementing circulating cooling and temperature replenishment in a grain depot using a natural cold source. Using the aforementioned circulating cooling and temperature replenishment system for grain depot 1 utilizing a natural cold source, the method includes the following steps:

[0059] Step 1: Input the preset temperature value of grain depot 1 through the controller display screen, so that the controller stores the level value representing the preset temperature;

[0060] Step 2: Simultaneously start the fans of delivery pump 5 and cooling tower 3;

[0061] Step 3: Temperature sensor 16 transmits an electrical signal representing the real-time temperature of grain depot 1 to the controller. When the electrical signal is lower than the level value, the controller sends a command to the frequency converter of the conveying pump 5 motor to reduce the speed of the conveying pump 5 motor. Through integral feedback control, the temperature of grain depot 1 is stabilized at the preset temperature.

[0062] In this embodiment, specifically, the low-temperature environment of the grain depot 1 is controlled by this cooling method to prevent moisture loss from the grain and to prevent the grain from becoming moldy due to high temperature, thus ensuring the quality of the stored grain.

[0063] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A system for circulating cooling and temperature reduction of grain depots using natural cold sources, characterized in that, include: The grain depot is equipped with multiple sets of heat exchange tubes. The refrigeration unit includes a cooling tower, a liquid storage tank, and a delivery pump. The outlet of the cooling tower, the liquid storage tank, the delivery pump, and the lower end of the heat exchange tube are connected in sequence, and the upper end of the heat exchange tube is connected to the inlet of the cooling tower.

2. The system for circulating cooling and temperature reduction of grain depots using natural cold sources according to claim 1, characterized in that, The refrigeration unit also includes a distribution box, a vacuum pump, a finned tube radiator, and a condenser. The positions of the distribution box, the condenser, and the liquid storage tank are sequentially lower. The outlet of the cooling tower is connected to one end of the top wall of the distribution box via a first pipe. The other end of the top wall of the distribution box is connected to the inlet of the vacuum pump. The outlet of the vacuum pump is connected to one end of the heat exchange tubes of the finned tube radiator. The other end of the heat exchange tubes of the finned tube radiator is connected to the upper end of the first side wall of the condenser. The upper end of the second side wall of the condenser is connected to the top wall of the liquid storage tank. The bottom wall of the distribution box is connected to the lower side of the liquid storage tank.

3. The system for circulating cooling and temperature reduction of grain depots using natural cold sources according to claim 2, characterized in that, The bottom wall of the diversion box is connected to the lower end of the liquid storage tank via a U-shaped tube.

4. The system for circulating cooling and temperature reduction of grain depots using natural cold sources according to claim 2, characterized in that, It also includes a second pipe, one end of which is connected to the upper end of the other side wall of the condenser, and the other end is connected to the top wall of the liquid storage tank. The second pipe is equipped with a check valve.

5. The system for circulating cooling and temperature reduction of grain depots using natural cold sources according to claim 2, characterized in that, It also includes a pressure relief valve and a baffle. The baffle is disposed between the first side wall and the second side wall. There is a gap between the lower end of the baffle and the bottom wall of the condenser. The top wall of the condenser between the first side wall and the baffle is connected to the pressure relief valve.

6. The system for implementing circulating cooling and temperature reduction of a grain depot using a natural cold source according to any one of claims 1 to 5, characterized in that, Multiple sets of the heat exchange tube matrix are arranged inside the grain depot.

7. The system for implementing circulating cooling and temperature reduction of a grain depot using a natural cold source according to any one of claims 1 to 5, characterized in that, It also includes multiple temperature sensors, which are evenly distributed on the inner wall of the grain depot. The temperature sensors are electrically connected to the input terminal of the controller, and the output terminal of the controller is electrically connected to the delivery pump.

8. The system for implementing circulating cooling and temperature reduction of a grain depot using a natural cold source according to any one of claims 1 to 5, characterized in that, It also includes a first drain pipe, one end of which is connected to the lower end of the storage tank, and the other end of which is connected to a first drain valve.

9. The system for circulating cooling and temperature reduction of a grain depot using a natural cold source according to claim 2, characterized in that, It also includes a second drain pipe, one end of which is connected to the lower end of the condenser, and the other end of which is connected to a second drain valve.

10. A method for implementing circulating cooling and temperature reduction in a grain depot using a natural cold source, characterized in that, The system for circulating cooling and temperature reduction of a grain depot using a natural cold source, as described in claim 7, includes the following steps: Step 1: Input the preset temperature value of the grain depot through the controller display screen, so that the controller stores the level value representing the preset temperature; Step two: Simultaneously start the delivery pump and the cooling tower fan; Step 3: The temperature sensor transmits an electrical signal representing the real-time temperature of the grain depot to the controller. When the electrical signal is lower than the level value, the controller sends a command to the frequency converter of the delivery pump motor to reduce the speed of the delivery pump motor. Through integral feedback control, the temperature of the grain depot is stabilized at the preset temperature.

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