In a lithium bromide refrigeration system, which substance acts as the refrigerant?

In a lithium bromide refrigeration system, water acts as the refrigerant. This type of system is commonly used in absorption refrigeration applications, where lithium bromide serves as the absorbent. The process relies on the evaporative cooling of water, which absorbs heat from the environment and effectively lowers the temperature within the system.

Water is circulated and evaporates within the evaporator under low pressure, absorbing heat and providing the cooling effect. As the water vapor forms, it is then absorbed by the lithium bromide solution, which helps regenerate more water in a distillation process. This distinction is crucial as it highlights the operational cycle of a lithium bromide absorption refrigeration system, and why water is classified as the refrigerant in this context.

In contrast, ammonia, carbon dioxide, and Freon are used in different types of refrigeration systems, such as vapor-compression systems, and are not applicable in the context of lithium bromide systems.