How to save energy in fruit and vegetable cold storage?
Author:Cold Storage Panel Supplier | DaChang / Categories:Support / Views :48063
There are many factors that need to be considered for energy saving in cold storage, including the performance of the cold storage refrigeration system, the selection of refrigerant, the selection of compressor condenser and evaporator, the scale and layout of cold storage, the type and thickness of insulation layer, To improve the refrigeration efficiency of the cold storage, all factors should be taken into consideration, such as the number of times of entering and exiting the goods, the thermal insulation performance of the outer door, and so on. These comprehensive factors can be summed up in two simple terms:
1. Reduce the cold load of the cold storage;
2. Selection of cold storage equipment.
The following is an introduction to the energy saving of fruit and vegetable cold storage:
Fruit and vegetable mini cold storage refers to the cold storage panels refrigeration units, evaporators, etc., which are pre-manufactured in the factory, and then installed at the agricultural production site to become assembled cold storage or civil cold storage or semi-assembled and semi-civilized cold storage, and the storage capacity is generally less than 200 cubic meters Rice is used in cold storage for preservation and storage. Classified by design temperature, Guoshu mini cold storage is high-temperature cold storage. Mini cold storage is composed of a refrigeration system, warehouse, control system, etc. The following points should usually be noted during cold storage installation:
1. The cooling capacity of the cold storage through the enclosure structure is proportional to the unit heat flow of the cold storage enclosure structure. Therefore, more efforts should be made to reduce the unit heat flow index of the cold storage enclosure structure of the cold storage. To reduce the unit heat flow of the envelope structure, firstly, the thermal conductivity of the insulation material should be small, and secondly, the envelope structure layer should be thicker. However, the thickness should generally not be too thick, otherwise, problems such as increased construction costs and wasted space will occur. Therefore, it is necessary to select insulation materials within a suitable thickness range. Under normal circumstances, insulation materials are required to have low thermal conductivity, low water absorption, good low-temperature resistance, and low cost. Commonly used cold storage insulation materials include rice husk, polystyrene foam, polyurethane rigid foam, and so on. Rice husk is convenient to obtain materials but has low thermal resistance, easy to absorb moisture, and large amount. The construction of the library is laborious and time-consuming, and the cost conversion is actually not lower than polystyrene; there are many polystyrene foam manufacturers, easy to purchase, and thermal resistance is Larger, moderate price, and easy to construct and install; polyurethane rigid foam has the largest thermal resistance and the best thermal insulation performance, but the price is high.
2. Moisture-proof and vapor insulation of the cold storage enclosure structure It is also necessary to take moisture and vapor insulation measures for the cold storage enclosure structure, otherwise the insulation performance of the insulation material will deteriorate. This is the reason why the heat preservation performance of the cold storage body is good when it is first used, but the heat preservation effect becomes worse after using it for a period of time. Since water vapor permeates from the high-temperature side to the low-temperature side, the moisture-proof vapor barrier should be placed on the side with the higher temperature of the insulation layer.
3. The evaporating pressure and temperature of the cold storage are corresponding to the evaporating pressure. After knowing the evaporating pressure, the evaporating temperature can be obtained by looking up the table. Under the condition of a certain temperature in the cold storage warehouse, the temperature difference (the difference between the evaporating temperature and the warehouse temperature) is reduced, the evaporating temperature can be increased accordingly, and the refrigeration capacity of the cold storage refrigerator will be increased, that is, the cycle efficiency will be improved. It also saves power.
4. Cold storage defrosting operation. Generally speaking, when the frost layer on the evaporator surface has no significant resistance to the air, and the airflow through the evaporator has not been reduced, the effect of the frost layer is not serious, so defrosting is not necessary; When the airflow is significantly reduced, defrost should be carried out. The greater the humidity of the air, the greater the difference between the temperature of the evaporator and the temperature of the cold storage, and the easier it is to frost on the evaporator. Combined with the preservation process, the use of packaged cold storage as much as possible can reduce the dry consumption of fruits and vegetables and reduce the number of defrosting of the evaporator. In fact, it also played a role in the energy saving of cold storage.
5. Different fruits and vegetables have different storage temperatures, and each type of fruit and vegetable also has a temperature range suitable for its storage. Without affecting the quality of fruits and vegetables, energy-saving cold storage should use a higher storage temperature. As the temperature of the cold storage is high, the evaporation temperature of the refrigeration system will increase accordingly, the refrigeration capacity of the refrigerator will be increased, and the cycle efficiency will of course be improved. Increasing the temperature of the cold storage is more important, it can also reduce the heat transfer to the outside through the storage body. The utilization rate of the energy-saving cold storage warehouse is the ratio of the actual volume of fruits and vegetables to the effective volume of the warehouse. The volume utilization rate of the mini cold storage is generally not less than 0.3, and of course, it cannot be too high, otherwise, it will be difficult to cool down. When the volume of the fruits and vegetables to be stored changes greatly, they should be divided into two or more cold storage rooms. In addition, it is necessary to choose a reasonable storage period, which is self-evident for the energy saving of cold storage.