The principle or general use of lithium bromide absorption unit!!![Thanks]

, Characteristics of lithium bromide solution In the lithium bromide absorption refrigerator, the lithium bromide solution is used as the absorbent, and water is used as the refrigerant to produce a cold effect and to absorb the refrigerant vapor after the cold effect is produced. Therefore, water and lithium bromide solution form the working fluid pair in the refrigerator. 1. Lithium bromide solution has a corrosive effect on ordinary metals. The corrosion is more serious especially in the presence of oxygen. 2. Lithium bromide aqueous solution is formed by dissolving solid lithium bromide solute in a water solvent. Under normal pressure, the boiling point of water is 100°C, while the boiling point of lithium bromide is 1265°C. Lithium bromide for refrigeration applications is generally supplied in the form of aqueous solution. Appearance: colorless transparent liquid ； Concentration not less than 50% ； The pH value of the aqueous solution is above 8. 3. When lithium bromide is dissolved to saturation at 20°C, the amount is 111.2 grams, that is, the solubility of lithium bromide is 111.2 grams. The solubility is related to the characteristics of the solute and solvent, as well as the temperature. It generally increases as the temperature increases. When the temperature decreases, the solubility decreases, and lithium bromide crystals will precipitate in the solution to form a crystallization phenomenon. This is very important in the bromine cooler. You must pay attention to the crystallization phenomenon during operation, otherwise it will often affect the normal operation of the refrigerator. 2. Lithium bromide refrigeration principle The lithium bromide absorption refrigeration principle is similar to the vapor compression refrigeration principle. They both use liquid refrigerant to evaporate and vaporize under low temperature and low pressure conditions to absorb the heat load of the refrigerant to produce a refrigeration effect. The difference is that lithium bromide absorption refrigeration uses a binary solution composed of "lithium bromide-water" as a working fluid pair to complete the refrigeration cycle. In the binary working fluid circulating in the lithium bromide absorption refrigerator, water is the refrigerant. Water evaporates in a vacuum state and has a low evaporation temperature (6°C), thereby absorbing the heat load of the refrigerant and reducing its temperature. Lithium bromide aqueous solution is an absorbent that strongly absorbs water vapor at normal and low temperatures, but can release the absorbed water at high temperatures. The cycle of absorption and release begins over and over again, and the refrigeration cycle continues. The heat in the refrigeration process is steam, which can also be called power. 3. Working principle of double-effect lithium bromide refrigerator Double-effect lithium bromide refrigerator is generally a three-cylinder type. The main components are made of: It consists of high-pressure generator, low-pressure generator, condenser, absorber, evaporator, high-temperature heat exchanger, low-temperature heat exchanger, condensate water regenerator, refrigerant water cooler, generator pump, absorber pump, evaporator pump and electrical control system. The principle of refrigeration is: The dilute solution in the absorber is transported by the generator pump to the high-temperature heat exchanger and the low-temperature heat exchanger in two ways. The dilute solution entering the high-temperature heat exchanger is heated by the high-temperature concentrated solution flowing out of the high-pressure generator and then enters the high-pressure generator. The dilute solution entering the low-temperature heat exchanger is heated by the concentrated solution flowing out from the low-pressure generator, and then continues to heat up through the condensate recuperator, and then enters the low-pressure generator. 　　The dilute solution entering the high-pressure generator is heated by the working steam, and the solution boils to generate high-temperature refrigerant vapor, which is introduced into the low-pressure generator. After heating the dilute solution in the low-pressure generator, it enters the condenser through throttling and is cooled and condensed into refrigerant water. 　　The dilute solution entering the low-pressure generator is heated by the high-temperature refrigerant steam generated by the high-pressure generator, and the low-temperature refrigerant steam generated directly enters the condenser, where it is also cooled and condensed into refrigerant water. The refrigerant water produced by the high and low pressure generators is combined in the condenser water collecting pan, mixed and introduced into the evaporator. 　　The working steam used to heat the dilute solution in the high-pressure generator condenses and enters the condensate pipeline through the condensate regenerator. The dilute solution in the high-pressure generator is heated to evaporate the refrigerant vapor, causing the concentration to increase into a concentrated solution, which is then introduced into the absorber through the high-temperature heat exchanger. The dilute solution in the low-pressure generator is heated up to release the refrigerant vapor and becomes a concentrated solution, which then enters the absorber through the low-temperature heat exchanger. The concentrated solution is mixed with the original solution in the absorber to form an intermediate concentration solution. The mixed solution is sucked by the absorber pump and transported to the spray system. It is sprayed on the outer surface of the absorber tube cluster, absorbs the refrigerant vapor evaporated from the evaporator, and becomes a dilute solution again to enter the next cycle. The absorption heat generated during the absorption process is taken out of the refrigeration system by the cooling water, completing the circulation process of the lithium bromide solution from a dilute solution to a concentrated solution, and then back to the dilute solution. That is, the thermal compression cycle process. 　　The refrigerant vapor generated by the high and low pressure generator condenses on the outer surface of the condenser tube cluster. The cooling water flowing through the tube cluster absorbs the condensation heat generated during the condensation process and is carried outside the refrigeration system. The condensed refrigerant water is collected through the throttling device and sprayed on the outer surface of the evaporator tube cluster. Due to the low pressure inside the evaporator, part of the refrigerant water absorbs the heat of the refrigerant water and produces a partial refrigeration effect. Most of the refrigerant water that has not yet evaporated is sprayed on the outer surface of the evaporator tube cluster by the evaporator pump, absorbs the heat of the refrigerant water flowing through the tube cluster, evaporates into refrigerant vapor, and enters the absorber. 　　The heat of the refrigerant water is absorbed to lower the water temperature, thereby achieving the purpose of refrigeration and completing the refrigeration cycle. The intermediate concentration mixed solution is sprayed in the absorber to absorb the refrigerant vapor, leaving the evaporator in a low-pressure state. After the solution absorbs the refrigerant vapor, it relies on the compression system to regenerate refrigerant vapor. This ensures the cycle of the refrigeration process. 4. Classification of lithium bromide refrigerators There are many classification methods for lithium bromide absorption refrigerators.: According to the energy used, it can be divided into steam type, hot water type, direct combustion type (fuel, gas) and solar type. ； According to the degree of energy utilization, it can be divided into single-effect type and double-effect type. ； According to the layout of each heat exchanger, it can be divided into single-cylinder type, double-cylinder type, and three-cylinder type. ； According to the scope of application, it can be divided into chilled water models and cold and warm water models. At present, more and more are integrating the above classifications, such as steam single-effect type, steam double-effect type, direct-fired cold and warm water unit, etc.