An ice making machine enhanced heat transfer system and process optimization method

Abstract

The present invention discloses an enhanced heat transfer system for an ice maker and a process optimization method, comprising an ice making system and an ice melting system. The ice making system comprises a gas-liquid separator, a compressor, a filter, a condenser, a diverter, an ice maker evaporator, and a second electric three-way valve. The ice melting system comprises a heat exchanger, a pump, a water tank, and an air-temperature heat exchanger. The gas-liquid separator is connected to the condenser via the compressor; the compressor is connected to the condenser via the filter; the condenser is connected to the ice maker evaporator via the diverter; the ice maker evaporator is connected to the heat exchanger via the second electric three-way valve, and the heat exchanger is connected to the input end of the gas-liquid separator; the heat exchanger is connected to the water tank via the pump; the filter is connected to the condenser via the first electric three-way valve; and the first electric three-way valve is also connected to the air-temperature heat exchanger. The present invention can not only save the time required for ice making, but also improve ice making efficiency and ice melting effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of refrigeration, and in particular relates to an ice making machine enhanced heat transfer system and a process optimization method. Background Art

[0002] With the development of society and the continuous improvement of people's living standards, the domestic market demand for ice is extremely large, with a wide range of applications, including marine fishing operations, cold chain transportation, seafood markets, food, aquaculture, and the chemical industry. Looking specifically at the fishery industry, based on estimated ice usage from 1997 to 2016, it increased from 5.89 million tons to 13.28 million tons. We have forecast ice usage from 2020 to 2030 to predict ice demand over the next 10 years. It is estimated that fishery ice usage will reach 19.27 million tons in 2030, a 28.89% increase from 14.95 million tons in 2020. Furthermore, according to an article on Food Merchants Network, at the retail level, 120 liters of ice are used for every 800 liters of fish. By 2030, my country's aquatic products are expected to require 14.19 million tons of ice. Judging from the above data, my country's ice market in the fishery and aquatic products industry alone is already very large; in 2020, my country's annual output of commercial ice-making machines exceeded 150,000 units, and the market size has exceeded 2 billion yuan; at the same time, various industries have higher and higher requirements for ice quality, so the requirements for "high performance", "low failure rate" and "hygiene" of ice-making machines are becoming more and more urgent.

[0003] However, the current ice making machines have problems such as the evaporator flow channel being too thick, low heat transfer efficiency, slow ice making speed, high consumables, and uneven ice melting. Therefore, conducting research on enhanced heat transfer of ice making machines can not only save resources and improve resource utilization efficiency, but also be an objective requirement for enterprises to respond to national policies. It is also an inevitable choice for enterprises to adapt to market needs, reduce costs, increase benefits, and enhance product competitiveness.

[0004] Chinese patent application CN201600077U discloses a heat exchange surface for a flake ice machine evaporator, comprising a refrigerant-side heat exchange surface and an ice-making-side heat exchange surface. This invention enhances the evaporator's heat transfer capacity and increases the heat exchange rate per unit area. However, this invention requires high technical optimization requirements, making its implementation in specific ice-making projects difficult. The present invention, on the other hand, is simple and easy to implement, both in terms of ice machine evaporator design and process implementation.

[0005] An evaporator for a small ice maker (CN2769790Y) includes a connecting pipe and an evaporator tube. This invention can increase the heat exchange efficiency of the evaporator tube and reduce manufacturing costs. However, this invention is only applicable to evaporators for household ice makers. For actual ice production companies, the scale of ice production is too small to be feasible.

[0006] An ice-making machine ice-melting device and its ice-melting process (CN103913026A) includes an ice tray, a water receiving trough, and an ice storage bucket. This invention uses a warm water spray method to melt ice quickly. However, the ice-melting equipment designed in this invention is only suitable for making small ice cubes and has strict requirements for controlling the warm water temperature. Excessively high temperatures can cause uneven heating of the ice cubes during the melting process, resulting in ice marks and cracks.

[0007] A direct-cooling block ice machine (CN207095112UA) utilizes thermal fluorination to melt ice. This invention utilizes a compressor to release heat to the aluminum plate of the ice machine's evaporator, achieving the desired effect. However, this invention is prone to problems such as uneven flow distribution and excessively long cooling channels during the melting process, resulting in incomplete melting and incomplete ice cubes. Summary of the Invention

[0008] The purpose of the present invention is to address the hidden dangers and shortcomings of the existing ice-making machine evaporator ice-making device and ice-making process mentioned above, and to provide an ice-making machine heat transfer enhancement and process optimization design and device, to upgrade the ice-making machine technology and optimize the design of the heat exchange flow channel and process as well as the equipment load adjustment, so as to achieve the purposes of improving heat transfer efficiency, shortening ice-making time, reducing material loss, saving electricity consumption, etc., and realizing one-button start of ice making, integrated control of ice making and ice melting, real-time monitoring, and safe operation.

[0009] The present invention is achieved through at least one of the following technical solutions.

[0010] An ice making machine enhanced heat transfer system includes an ice making system and an ice melting system;

[0011] The ice making system includes a gas-liquid separator, a compressor, a filter, a condenser, a diverter, an ice maker evaporator, and a second electric three-way valve; the ice melting system includes a heat exchanger, a pump, a water tank, and an air-temperature heat exchanger;

[0012] The gas-liquid separator is connected to the condenser through a compressor; the compressor is connected to the condenser through a filter; the condenser is connected to the ice maker evaporator through a diverter;

[0013] The ice maker evaporator is connected to the heat exchanger through the second electric three-way valve, and the heat exchanger is connected to the input end of the gas-liquid separator; the heat exchanger is connected to the water pool through the pump; the filter is connected to the condenser through the first electric three-way valve; the first electric three-way valve is also connected to the air-temperature heat exchanger, and the output end of the air-temperature heat exchanger is connected to the diverter.

[0014] Furthermore, a second temperature sensor is provided at the output end of the condenser; and a second pressure sensor and a pressure visual meter (5) and a first temperature sensor are provided on the pipeline connecting the compressor and the filter.

[0015] Furthermore, the compressor is a variable frequency compressor.

[0016] Furthermore, during the ice-melting process, the air-temperature heat exchanger is connected to the diverter through a second pressure reducing valve.

[0017] Furthermore, the aluminum frost plate of the heat exchange tube in the ice maker evaporator is a circular small hole flow channel with a diameter of 4mm to 8mm.

[0018] Furthermore, the heat exchange tube in the ice maker evaporator is a circular hole.

[0019] Furthermore, the heat exchange plates in the ice maker evaporator are connected in parallel arrangement up and down, and the heat exchange tubes are grouped into 2 to 4 small holes; the diverter head divides the main refrigerant into several streams that enter the corresponding channels after the heat exchange tubes and aluminum plates in the ice maker evaporator have been grouped, and then enter the corresponding group flow channels of the next heat exchange plate.

[0020] Furthermore, the condenser is connected to the diverter through a first one-way valve, and the condenser is connected to the first one-way valve through an expansion valve.

[0021] Further, the second electric three-way valve is connected to the heat exchanger through a first pressure reducing valve.

[0022] The process optimization method for implementing the ice making machine enhanced heat transfer system includes the following steps:

[0023] During the ice-making process: the electric three-way valve is closed, the refrigerant comes out of the gas-liquid separator and enters the compressor to be compressed into a high-temperature and high-pressure gaseous refrigerant; after being condensed by the condenser, the temperature drops and then enters the expansion valve for expansion. The expanded refrigerant becomes a low-temperature and low-pressure liquid refrigerant; then it enters the ice-making machine to make ice, and the temperature of the refrigerant after ice making rises, and enters the gas-liquid separator to complete the cycle;

[0024] During the ice-melting process: the electric three-way valve is in the open state, the refrigerant comes out of the gas-liquid separator and enters the compressor to be compressed into a high-temperature and high-pressure gaseous refrigerant; then it enters the air-temperature heat exchanger to cool down, and then it is reduced in pressure through the second pressure reducing valve. At this time, the temperature is lowered, and then it enters the ice maker. At this time, the ice maker acts as a condenser and uses the heat of the refrigerant to melt the ice; after the refrigerant comes out of the ice maker, the temperature drops, and then it enters the first pressure reducing valve to reduce pressure, and both the pressure and temperature are reduced. Then it enters the heat exchanger to exchange heat with the water in the pool. After the heat exchange, the temperature rises and it enters the gas-liquid separator to complete the cycle.

[0025] Compared with the existing technology and status quo, the present invention has the following beneficial effects:

[0026] 1. Save refrigerant costs. This process system uses circular small hole ice machine heat exchange tubes, which reduces the refrigerant filling volume by 60-80%, thereby saving refrigerant costs and reducing ice making costs.

[0027] 2. Maintain minimum load and save electricity. By monitoring the changes in compressor outlet temperature and pressure as well as the gas-liquid phase of the refrigerant, the load of the condenser is adjusted to maintain the minimum load to achieve the purpose of saving electricity.

[0028] 3. Wide system applicability. Research on enhanced heat transfer in ice machines has resulted in circular holes in the evaporator heat exchange tubes, which significantly improves the heat exchange tubes' pressure resistance and allows for a wider range of refrigerant applications.

[0029] 4. Faster ice making and melting time. The water in the pool of this system is pre-cooled in advance and can also be used for ice making. At the same time, the system uses integrated hot fluorine ice making and melting, which saves more time than conventional hot fluorine ice making and melting.

[0030] 5. The entire device has a high degree of automation. The device uses thermal fluorine ice making and ice melting in an integrated manner, including one-touch start function, ice making and ice melting switching function, etc. Compared with traditional ice making, the required labor is less, which reduces many human errors and saves labor costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Design and device for enhanced heat transfer and process optimization of an ice making machine;

[0032] Figure 2 The diverter head branches the refrigerant main pipeline into the ice maker;

[0033] Figure 3 The arrangement of the heat exchange tubes of the ice machine evaporator and the refrigerant flow direction;

[0034] The figure shows: 1-first pressure sensor and pressure visual gauge, 2-gas-liquid separator, 3-solenoid valve, 4-compressor, 5-second pressure sensor and pressure visual gauge, 6-first temperature sensor, 7-filter, 8-first electric three-way valve, 9-condenser, 10-second temperature sensor, 11-expansion valve, 12-first check valve, 13-third temperature sensor, 14-third pressure sensor, 15-diverter, 16-ice maker evaporator, 17-fourth temperature sensor, 18-second electric three-way valve, 19-first pressure reducing valve, 20-heat exchanger, 21-second check valve, 22-fifth temperature sensor, 23-pump, 24-water tank, 25-air temperature heat exchanger, 26-second pressure reducing valve, 27-third check valve. DETAILED DESCRIPTION

[0035] For a better understanding of the present invention, the present invention will be further described below with reference to the accompanying drawings and embodiments. However, the scope of protection claimed by the present invention is not limited to the scope described in the embodiments.

[0036] An enhanced heat transfer system for an ice maker according to this embodiment, such as Figure 1 As shown, it includes ice making system and ice melting system;

[0037] The ice making system includes a first pressure sensor and a pressure visual gauge 1, a gas-liquid separator 2, a solenoid valve 3, a compressor 4, a second pressure sensor and a pressure visual gauge 5, a temperature sensor 6, a filter 7, a first electric three-way valve 8, a condenser 9, a temperature sensor 10, an expansion valve 11, a one-way valve 12, a third temperature sensor 13, a third pressure sensor 14, a diverter 15, an ice making machine evaporator 16, a fourth temperature sensor 17, and a second electric three-way valve 18;

[0038] The output end of the gas-liquid separator 2 is connected to the input end of the compressor 4 through the solenoid valve 3, and the output end of the compressor 4 is connected to the input end of the condenser 9 through the first electric three-way valve 8; the compressor 4 is connected to the first electric three-way valve 8 through the filter 7;

[0039] The output end of the condenser 9 is connected to the input end of the ice maker evaporator 16 through the diverter 15; a first one-way valve 12 is provided on the pipeline connecting the diverter 15 and the condenser 9, and a third temperature sensor 13 and a third pressure sensor 14 are provided on the pipeline close to the diverter 15; the output end of the ice maker evaporator 16 is provided with the fourth temperature sensor 17; the output end of the ice maker evaporator 16 is connected to the output end of the gas-liquid separator 2 through the second electric three-way valve 18.

[0040] The pipeline connecting the condenser 9 and the first one-way valve 12 is provided with the expansion valve 11; a temperature-sensing package reverse-control expansion valve is provided at the ice-making machine evaporator 16, which is the dotted line in the figure.

[0041] As another preferred embodiment, the gas-liquid separator 2 is also provided with the first pressure sensor and the pressure visual meter 1 for detecting the pressure of the gas-liquid separator 2; the aluminum freezing plate of the heat exchange tube in the ice maker evaporator 16 is a circular small hole flow channel with a diameter of 4mm to 8mm, which does not affect the heat exchange performance, reduces the amount of consumables, and can save 15 to 30% of materials.

[0042] As another preferred embodiment, the pipe connecting the compressor 4 and the filter 7 is equipped with a second pressure sensor, a pressure gauge 5, and a first temperature sensor 6 for detecting the corresponding pressure and temperature. This embodiment utilizes a variable-frequency compressor 4, whose operating power varies with system temperature, saving 20% ​​of the power consumption per unit of ice making. The heat exchange tubes in the ice maker's evaporator 16 have circular holes, increasing pressure resistance by 40-50%, reaching over 4 MPa. This reduces refrigerant filling by 60-80%, significantly saving refrigerant costs.

[0043] The heat exchange plates in the ice maker evaporator 16 are connected in parallel up and down, and the heat exchange tubes are grouped into 2 to 4 small holes; the diverter 15 divides the main refrigerant into 5 streams and enters the corresponding channels of the heat exchange tube aluminum plates in the ice maker evaporator 16 after they have been grouped, and then enters the corresponding group flow channels of the next heat exchange plate, so as to realize the purpose of connecting the flow channels in different heat exchange plates in series, thereby achieving the effect of uniform flow distribution. The process is as follows Figure 2 , Figure 3 As shown, ① to ⑤ represent 5 logistics.

[0044] A second temperature sensor 10 is provided at the output end of the condenser 9; the outlet temperature change of the compressor 4 is monitored by the pressure sensor and the pressure visual meter 5 and the temperature sensor 6 and the temperature sensor 10, thereby ensuring that the refrigerant at the outlet of the condenser 9 is pure liquid, so as to achieve the effect of adjusting the load of the condenser 9, maintaining its minimum load, and saving electricity.

[0045] The ice-melting system includes a first pressure-reducing valve 19 , a heat exchanger 20 , a second one-way valve 21 , a fifth temperature sensor 22 , a pump 23 , a water tank 24 , an air-temperature heat exchanger 25 , a second pressure-reducing valve 26 , and a third one-way valve 27 .

[0046] The output of the second electric three-way valve 18 is connected to the input of a heat exchanger 20 via the first pressure-reducing valve 19. The output of the heat exchanger 20 is connected to the output of the gas-liquid separator 2 via the second one-way valve 21. The heat exchanger 20 is connected to a water reservoir 24 via the pump 23. The water in the water reservoir 24 recovers the refrigerant cooling capacity in the evaporator for use in ice making. The thermal fluoride ice formation in this process is faster than conventional methods, shortening ice making time by 5-10%.

[0047] The fifth temperature sensor 22 is provided on the pipeline connecting the second one-way valve 21 and the gas-liquid separator 2;

[0048] One end of the first electric three-way valve 8 is also connected to an air-temperature heat exchanger 25, which is connected to the input end of the diverter 15 via a second pressure-reducing valve 26 and a third one-way valve 27. The second pressure-reducing valve 26 regulates the temperature of the refrigerant entering the ice maker's evaporator 16, thereby preventing ice marks and cracks in the produced ice cubes caused by excessive refrigerant temperature.

[0049] The process controls the opening and closing of the first electric three-way valve 8 and the second electric three-way valve 18 by specifying the ice making time, so that the system can realize the self-control ice making / melting function, thereby making ice making and melting more convenient and quick, and also saving manual control costs.

[0050] The system is applicable to various types of refrigerants, including CO2 and various R-type refrigerants such as R22, R507, R410a, various light hydrocarbon refrigerants such as ethane, propane, and their mixtures.

[0051] Another specific example is to use R22 refrigerant with a daily output of 10 tons of ice and 2.2 tons / hour. Figure 1 As shown:

[0052] During the ice-making process, the electric three-way valves (8, 18) are in a closed state, 2.2 t / h of gaseous R22 comes out of the gas-liquid separator 2 and enters the compressor 4 for compression, the pressure rises to 1.6 MPa, and the temperature rises to 104-115°C; after condensation in the condenser, the temperature drops to about 40°C, and then enters the expansion valve 11 for expansion, the pressure of the expanded R22 drops to 0.23 MPa, and the temperature is -22°C; then enters the ice-making machine 16 to make ice, the temperature of the R22 after ice making rises to about -21°C, and enters the gas-liquid separator 2 to complete the cycle.

[0053] During the ice-melting process, the electric three-way valves (8, 18) are in the open state, 2.2 t / h of gaseous R22 comes out of the gas-liquid separator 2, enters the compressor 4 for compression, the pressure rises to 1.6 MPa, and the temperature rises to 104-115°C; then enters the air-temperature heat exchanger 25 to cool to about 45°C, then passes through the pressure reducing valve 26 for pressure reduction, the pressure drops to 0.8-1.6 MPa, and the temperature drops to 29-45°C, then enters the ice-making machine 16, at which time the ice-making machine 16 acts as a condenser, using the heat of the refrigerant to melt ice; after the refrigerant R22 comes out of the ice-making machine 16, the temperature drops to 15-40°C, then enters the pressure reducing valve 19 for pressure reduction, the pressure drops to 0.23 MPa, and the temperature drops to about -22°C, then enters the heat exchanger 20, exchanges heat with the water in the water tank 24, and the temperature rises to above -20°C after the heat exchange, and enters the gas-liquid separator 2 to complete the cycle.

[0054] This invention addresses the shortcomings of current ice-making machines, such as slow ice-making speed, high material consumption, and uneven ice melting, by upgrading the ice-making machine's technology and optimizing the heat exchange flow path, process, and equipment load regulation. This invention not only reduces ice-making time, improves ice-making efficiency, and enhances ice melting, but also reduces metal material consumption. Furthermore, research on enhanced heat transfer in ice-making machines can conserve resources and improve resource utilization efficiency.

[0055] The above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications may be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the claims of the present invention.

Claims

1. An ice making machine enhanced heat transfer system, characterized by: Including ice making system and ice melting system; The ice making system comprises a gas-liquid separator (2), a compressor (4), a filter (7), a condenser (9), a diverter (15), an ice making machine evaporator (16), and a second electric three-way valve (18); the ice melting system comprises a heat exchanger (20), a pump (23), a water tank (24), and an air-temperature heat exchanger (25); The gas-liquid separator (2) is connected to the condenser (9) via the compressor (4); the compressor (4) is connected to the condenser (9) via the filter (7); the condenser (9) is connected to the ice maker evaporator (16) via the diverter (15); The ice maker evaporator (16) is connected to the heat exchanger (20) via the second electric three-way valve (18), and the heat exchanger (20) is connected to the input end of the gas-liquid separator (2); the heat exchanger (20) is connected to the water tank (24) via the pump (23); the filter (7) is connected to the condenser (9) via the first electric three-way valve (8); the first electric three-way valve (8) is also connected to an air-temperature heat exchanger (25), and the output end of the air-temperature heat exchanger (25) is connected to the diverter (15); The output end of the condenser (9) is provided with a second temperature sensor (10); the pipe connecting the compressor (4) and the filter (7) is provided with a second pressure sensor and a pressure visual meter (5) and a first temperature sensor (6); the aluminum freezing plate of the heat exchange tube in the ice maker evaporator (16) is a circular small hole flow channel with a diameter of 4mm to 8mm.

2. The ice making machine enhanced heat transfer system according to claim 1, characterized in that: The compressor (4) is a variable frequency compressor.

3. The ice making machine enhanced heat transfer system according to claim 1, characterized in that: During the ice-melting process, the air-temperature heat exchanger (25) is connected to the diverter (15) via the second pressure reducing valve (26).

4. The ice making machine enhanced heat transfer system according to claim 1, characterized in that: The heat exchange tube in the ice maker evaporator (16) is a circular small hole.

5. The ice making machine enhanced heat transfer system according to claim 1, characterized in that: The heat exchange plates in the ice maker evaporator (16) are connected in parallel arrangement up and down, and the heat exchange tubes are grouped into 2 to 4 small holes; the diverter (15) divides the main refrigerant into several streams that enter the corresponding channels of the heat exchange tube aluminum plates in the ice maker evaporator (16) after they have been grouped, and then enter the corresponding group flow channel of the next heat exchange plate.

6. The ice making machine enhanced heat transfer system according to claim 1, characterized in that: The condenser (9) is connected to the diverter (15) via a first one-way valve (12), and the condenser (9) is connected to the first one-way valve (12) via an expansion valve (11).

7. The ice-making machine enhanced heat transfer system according to claim 1, characterized in that: The second electric three-way valve (18) is connected to the heat exchanger (20) via the first pressure reducing valve (19).

8. A process optimization method for implementing the ice making machine enhanced heat transfer system according to claim 1, characterized in that: The following steps are involved: During the ice-making process: the electric three-way valve (8, 18) is in a closed state, the refrigerant comes out of the gas-liquid separator (2), enters the compressor (4) and is compressed into a high-temperature and high-pressure gaseous refrigerant; after being condensed by the condenser, the temperature drops and then enters the expansion valve (11) for expansion. The expanded refrigerant is a low-temperature and low-pressure liquid refrigerant; then it enters the ice-making machine evaporator (16) to make ice. After making ice, the temperature of the refrigerant rises and enters the gas-liquid separator (2) to complete the cycle; During the ice-melting process: the electric three-way valve (8, 18) is in the open state, the refrigerant comes out of the gas-liquid separator (2), enters the compressor (4) and is compressed into a high-temperature and high-pressure gaseous refrigerant; then enters the air-temperature heat exchanger (25) for cooling, and then passes through the second pressure reducing valve (26) for pressure reduction, at which time the temperature is reduced, and then enters the ice-making machine evaporator (16), at which time the ice-making machine evaporator (16) acts as a condenser, using the heat of the refrigerant to melt ice; after the refrigerant comes out of the ice-making machine evaporator (16), the temperature is reduced, and then enters the first pressure reducing valve (19) for pressure reduction, the pressure and temperature are reduced, and then enters the heat exchanger (20) to exchange heat with the water in the water pool (24), the temperature is increased after the heat exchange, and enters the gas-liquid separator (2) to complete the cycle.

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