Cold storage installation and maintenance are the basics, but energy saving and consumption reduction is the fundamental!

　　1. Energy-saving control for cold storage When the cold storage refrigeration system is operating, while the compressor’s energy-saving load is adjusted, such as the following points of attention: 　　1. Reasonably match the compressor and cold air under different working conditions and load conditions Machines and other equipment to prevent energy loss caused by 'big horse-drawn carts'. Among them, air coolers account for the largest proportion of energy consumption, about 38% to 23%. Example: Take a 10,000-ton cold storage as an example. The 10,000-ton cold storage is divided into 20 warehouses. Each warehouse has a storage capacity of 500t. Each warehouse is equipped with 2 air coolers, and each air cooler is equipped with 2.2kW axial flow. There are 3 fans and a total of 120 axial fans in the whole library. Since the air volume is proportional to the cooling capacity, and the fan is equipped with the maximum cooling load, during the first purchase period, the cooling capacity is relatively large, and the fans should all be turned on.　　 But when the cargo cooling processing is basically completed, the warehouse temperature has stabilized, and the number of axial fans should be reduced in time. If you use 2 less axial fans per warehouse, you can save 40 units with a total of 88kW, which consumes more energy than a 6AW-12.5 compressor and saves 25% of energy. In addition, multiple fans can easily generate heat, which increases the cooling energy consumption of the system.　　 Cold storage installation and maintenance are basic, but energy saving and consumption reduction are fundamental!　　2. Effective management of heat exchange equipment can also play an effective role in reducing energy consumption. Because when the evaporating temperature is -10℃, the compressor unit cooling capacity consumption will decrease by 2.5%～3.2% for every 1℃ decrease in the condensing temperature; when the condensing temperature is 30℃, every 1℃ increase in the evaporating temperature, the compressor unit consumption Electricity is reduced by 3.1% to 3.9%. It can be seen that good management of heat exchange equipment is of great significance to reducing energy consumption.

　　3. Measures to reduce energy consumption by heat exchange equipment: 　　 (1) When there is too much oil, release the oil in time: the thermal resistance of oil is much higher than that of metal, which is 20 times that of iron. The oil film attached to the surface of the heat exchanger will cause The condensation temperature rises and the evaporation temperature drops, resulting in an increase in energy consumption. When a 0.1mm oil film is attached to the surface of the condenser, the refrigeration compressor cooling capacity will drop by 16% and the power consumption will increase by 12.4%; when the oil film in the evaporator reaches 0.1mm, the evaporation temperature will drop by 2.5°C and the power consumption will increase by 11%. At the same time, the evaporation temperature is too low, so that the oil sludge is not easy to be brought back to the low-pressure circulation barrel after entering the evaporator, and it is easy to cause the evaporator to block. Therefore, it is necessary to avoid oil entering the heat exchange system as much as possible. (2) Timely exhaust air: The air in the condenser will increase the condensing temperature: when the air pressure in the system reaches 0.2MPa, the power consumption will increase by 18% and the cooling capacity will decrease by 8%. Therefore, every effort should be made to prevent air from entering the system. And promptly exhaust the infiltrated air.　　 (3) Regularly remove scale and clean the circulating pool: keep the condensate clean, when the condenser is scaled 1.5mm, the power consumption will increase by 9.7%.　　 (4) Timely defrosting: After the evaporator surface is frosted, the heat transfer will deteriorate, the evaporation temperature will drop, and the power consumption will increase.　　 (5) Use the low temperature at night in summer to cool down: When the temperature difference between day and night in the area is more than 10℃ in summer and autumn, reasonable use of low temperature at night will have obvious energy saving effect.　　4. On the premise of ensuring that the refrigeration load is met, the number of starting units should be reduced as much as possible to improve the operating efficiency of the compressor. Choose to open a compressor with a large refrigeration capacity instead of two compressors with a small refrigeration capacity; choose to open a single two-stage machine instead of two paired two-stage machines.

　　 5. Adjust the boot time. On the premise of not affecting the quality of food refrigeration, reduce the operating time of the refrigeration compressor during the day (preferably turn on at noon), and increase the operating time of the night refrigeration compressor, that is, select the low peak of power consumption (that is, turn on after the middle of the night); not only The cost is reduced, and the night condensing temperature is lower, which can reduce the power consumption of the compressor.

　　Second, reduce the loss of cold storage in the cold storage insulation

　　1, ensure the insulation performance of the cold storage enclosure structure: the cold storage has a good enclosure structure to ensure the low temperature in the cold storage The premise of the environment. When designing a new cold storage, thermal insulation materials with low thermal conductivity should be used as the enclosure structure, and the integrity of the enclosure structure should be paid attention to, and the generation of cold bridges and wall holes should be avoided as much as possible to reduce the transfer of heat from outside the storage to the inside. In turn, the loss of the cooling load of the cold storage enclosure structure is reduced.　　2. Reasonable start-up and control of proper evaporation temperature: Proper refrigeration temperature can reduce the temperature difference between the inside and outside of the warehouse, which is beneficial to reduce the cooling load and the electrical load of the refrigeration system.　　3. Timed and timely defrosting: During the operation of the air cooler, due to the gradual thickening of the frost layer, the heat transfer coefficient decreases, the air volume decreases, the fan power increases, and the cold output of the air cooler drops sharply. Therefore, the air cooler must defrost after running for a certain period of time.　　4. Reduce the cold air loss of the cold storage door: the cold storage door should be closed as soon as it is opened to reduce the load loss of opening the door. If the opening time of the cold storage door is doubled, the cold loss will increase several times. At the same time, the cold storage door will take a long time to open, and the high humidity air outside the storage will invade. It is easy to form frost and dew at the door opening, which will damage the storage body. structure. Studies have shown that the height of the refrigerator door has a much greater impact on the leakage of cold air than its width, so the height should be reduced as much as possible.　　The power of the electric heating wire of the refrigerator door has two options of anti-condensation and anti-freezing. The configuration power of the electric heating wire of the refrigerator door with different operating temperatures is different. If the appropriate heating power is selected, the energy can be saved by 2%. In order to reduce the energy loss and structural damage caused by the door opening, a hall or air curtain can be set at the door opening to reduce the intrusion of high temperature and high humidity air outside the warehouse, reduce the cooling load, and improve the efficiency of the system.