How to operate cold storage to save electricity

How to operate cold storage to save electricity

How can the cost of cold storage operation be reduced is a point of concern for many people. The operation cost of cold storage is mainly composed of electricity, maintenance, management fees and other miscellaneous items. Today, let's talk about how cold storage can save electricity.

　　Accurately and timely adjust the refrigeration system

In the actual operation of the refrigeration system, because the working conditions are constantly changing, only relying on the careful operation of the cold storage management personnel and accurately adjusting the operation of the refrigeration equipment can the refrigeration system always be in the most ideal working state and achieve high efficiency and energy saving effect.

　　 Use warehouses rationally to save energy and reduce consumption

The power consumption of the cold storage room is calculated according to the amount of cold consumption in the cold storage room. It usually includes two parts: one is the cold consumption during cargo cooling and cold storage; the other is the cold storage room itself (ie, the enclosure structure) and operation management Of cold consumption. The key to saving electricity is the utilization rate of cold storage rooms. Cold storage rooms with low utilization rate consume more cold and consume more electricity.

　　In actual operation, the power of the motor equipped with the compressor is selected according to the cooling capacity of the machine, that is, the cooling capacity of the warehouse is less than the cooling capacity of the refrigerator. When the cold storage is operating in the off-season, because there are less goods stored in the cold storage, the compressor runs as a "big horse-drawn cart", which wastes electrical energy. Therefore, in the off-season, the goods in several cold storage rooms can be combined according to the storage temperature in time to reduce energy consumption.

　　Energy saving of lighting system in cold storage

　　 Cold storage lighting should be based on safety, science and reasonableness, starting from the perspective of energy saving and environmental protection, and considering the area, height and temperature of the cold storage room. The lighting in the cold storage is generally concentrated in the work area. The lights should be turned off in time while ensuring the safety of operators to reduce the thermal load and power consumption of the warehouse. At the same time, try to use high-efficiency, low-consumption and pressure-resistant lighting fixtures to reduce the frequency of lamp replacement. The LED lighting system has the advantages of environmental protection and power saving, uniform illumination, good luminous efficiency at low temperatures, and high power supply efficiency. It is a very promising new light source and the development direction of the lighting system in the cold storage in the future.

　　Drain oil, descaling and air regularly to ensure good heat exchange effect

The data shows that when there is a 0.1mm thick oil film in the evaporator coil, in order to maintain the set temperature requirement, the evaporating temperature will drop by 2.5℃ and the power consumption will increase by more than 10%; when the water pipe wall in the condenser is fouled When it reaches 1.5mm, the condensing temperature will increase by 2.8℃ than the original temperature, and the power consumption will increase by 9.7%; when the refrigeration system is mixed with non-condensable gas and its partial pressure reaches 0.196mpa, the power consumption will increase by about 18 %. This shows the importance of regular oil discharge, descaling and air discharge in the refrigeration system of cold storage.

　　Reasonable adjustment and timely defrosting of cold storage evaporator

　　 Generally speaking, every 1°C increase in the evaporation temperature of the cold storage can save energy by 2%~2.5%. Therefore, on the premise that the product refrigeration process can be satisfied, the evaporation temperature can be increased as much as possible by adjusting the liquid supply.

　　The thermal resistance of the frost layer is generally much greater than that of the steel pipe. When the thickness of the frost layer is greater than 10mm, its heat transfer efficiency will drop by more than 30%. When the temperature difference between the inside and outside of the tube wall is 10℃ and the storage temperature is -18℃, the heat transfer coefficient k value of the tube evaporator is only about 70% of the original after running for one month. When the frost of the air cooler is particularly severe, not only the thermal resistance will increase, but also the flow resistance of the air will increase. In severe cases, the air cannot be supplied. Therefore, the surface of the evaporator should be defrosted in a timely manner. In the refrigeration system of large and medium-sized cold storages, the electric defrosting method with high energy consumption is generally not used, and the small freon refrigeration system can use the electric defrosting method to simplify the pipeline, but it should be configured appropriately according to the heat required for melting the frost layer Electric heating power.

　　Rational use of peak and valley electricity operation

　　 On the premise of not affecting the quality of the refrigerated objects, the cold storage can be operated at night at the "valley price" to reduce the operating time of the refrigeration compressor during the day and avoid the peak electricity consumption during the day. At present, the time-of-use electricity price system formulated by major provinces and cities in my country has a peak-to-valley price ratio of 3 to 4: 1, so cold storage devices or adjustment of the start-up time can be used to increase the utilization rate of "valley power" and reduce operating costs.

　　 Reasonable use of day and night temperature difference operation

　　 my country has a vast territory, and many areas have large temperature differences between day and night. Usually, the temperature difference between day and night in marine climate is 6~10℃, while in continental climate region, the temperature difference between day and night can reach 10~15℃. The ambient temperature at night is low, and the power-on time at night can be adjusted and prolonged according to the storage characteristics of the product. Because the condensation temperature is relatively low, it is beneficial to the energy saving of the cold storage.