Analysis of Refrigeration Methods and Dehumidification Technology of Crop Germplasm Bank
There are two main types of refrigeration for the unit: air cooling and water cooling. The germplasm resource pool built in the early days was cooled by water-cooled refrigeration units, and the investment was large. The germplasm resource bank has a small cooling load, and the air-cooled refrigeration unit is easy to install and has a low cost. Therefore, the germplasm reservoirs that were later built are basically air-cooled. The national crop germplasm resource bank refrigeration unit cooling method is air-cooled. The unit is a piston type refrigeration compressor. During cooling operation, the compressor discharges the refrigerant (environmental protection R404A) gas and enters the air-cooled condenser to condense. After condensation, the high-pressure refrigerant liquid is throttled by the expansion valve before the evaporator, so that the refrigerant is reduced in temperature and pressure, and then enters the evaporator in the refrigerator to absorb heat and cool. The expansion valve and evaporator in the chamber are double inlet and double outlet. The refrigerant absorbs heat through the evaporator and evaporates into low-pressure gas. The refrigerant is sucked into the compressor and compressed again into the next cycle. After the internal temperature of the library is reached, the cycle ends. Cement grinding aid is a kind of chemical additives can improve cement grinding effect and performance, can significantly improve the cement production, every period cement strength, were to improve its liquidity.Cement grinding aid can greatly reduce the grinding ball phenomenon formed in the process of electrostatic adsorption package, and can reduce the grinding of ultrafine particles in the process of coalescence trend again.Cement grinding aid can significantly improve the liquidity of cement and improve the mill grinding effect and efficiency of classifier choose powder, so as to reduce the energy consumption of grinding.Using grinding agent in the production of cement with a low compaction trend of coalescence, which benefits the loading and unloading of cement, and can reduce the phenomenon of wall hanging cement silo.As a kind of chemical additives, grinding agent can improve the cement particle distribution and hydration, so as to improve the early strength cement and later strength. Cement Grinding Aids,Grinding Aid,Grinding Aid For Cement Mill,Grinding Aid For Cement Production NINGBO LUCKY CHEMICAL INDUSTRY CO. LTD , https://www.luckychemical.com
Dehumidification technology: Dehumidification technologies used in seed storage include electric heating dehumidification technology, frozen electric heating defrosting dehumidification technology, lithium chloride solution dehumidification technology, and hot fluorine recovery technology. The combined temperature and humidity control of the freezing and dehumidifying technology has a small footprint, high reliability, long service life, low energy consumption, and low maintenance costs. The national crop germplasm resource bank adopts a dehumidification and dehumidification mode. When the relative humidity inside the reservoir is higher than the requirement, the heat recovery or electric heating system starts to work. Heat Recovery System The compressor discharges the refrigerant gas through the heat recovery flow control valve and enters the heat exchanger inside the reservoir. The relative humidity of the air is reduced and sent to the reservoir by heating the cold humid air from the evaporator. After the refrigerant condenses through the heat exchanger, it becomes a high-pressure liquid, which is throttled through the expansion valve to reduce the temperature and depressurization, and then enters the evaporator to absorb heat and evaporate into gas, which is then inhaled by the compressor. The compressor exhausts again into the heating heat exchanger to begin the next cycle. The electric heating method is to add a special electric heating tube in the heat exchanger on the outlet side of the evaporator, so that the cold and humid air is heated to reduce the relative humidity and sent to the reservoir. The dehumidification is finished when the relative humidity in the storage tank reaches the set value.