What properties of ammonia can make liquid ammonia a refrigerator?

What properties of ammonia can make liquid ammonia a refrigerator?

Ammonia is a commonly used industrial gas, which is often used as a refrigerant because of its good solubility and good refrigeration performance. The refrigeration system of liquid ammonia is usually called ammonia refrigeration system. This paper will introduce the properties of ammonia and why liquid ammonia can be used as a refrigerator.

chemical property

The molecular formula of ammonia is NH3, which is a colorless and irritating gas. Ammonia is an alkaline substance, which can react with acid to form salt and water. Ammonia is dissolved in water to form ammonia water, which is alkaline in nature.

The chemical properties of ammonia make it have important applications in many industrial processes. For example, ammonia can be used as raw material for glass, fertilizer, chemical fertilizer and gunpowder. At the same time, ammonia gas is often used as refrigerant, which produces refrigeration effect through evaporative cooling.

physical features

Compared with other refrigerants, liquid ammonia has good refrigeration performance. This is because the boiling point of liquid ammonia is very low, only -33C. This means that liquid ammonia can evaporate at a very low temperature, thus absorbing heat. When gas is compressed, it releases heat. This refrigeration process is called evaporative refrigeration.

In addition, the thermal conductivity of liquid ammonia is also high. This means that liquid ammonia can quickly transfer heat to the surrounding environment during refrigeration. Therefore, the liquid ammonia refrigeration system can quickly cool down.

refrigeration system

Liquid ammonia refrigeration system is widely used in industrial refrigeration. This refrigeration system includes four main components: liquid ammonia compressor, condenser, evaporator and throttle valve. These components interact to produce a cooling effect.

In the liquid ammonia refrigeration system, liquid ammonia is first compressed into high-pressure gas by a compressor. Then, the high-pressure gas is cooled by the condenser, thereby becoming liquid. The liquid liquid ammonia enters the evaporator through the throttle valve, and the liquid liquid ammonia in the evaporator becomes gaseous due to the influence of external heat, and absorbs the external heat to achieve the refrigeration effect.

To sum up, liquid ammonia plays an important role in the refrigeration process. The low boiling point and high thermal conductivity of liquid ammonia make it possible to evaporate heat at extremely low temperature and quickly transfer it to the surrounding environment. Through the liquid ammonia refrigeration system, we can use this refrigeration method in different industrial processes, so as to obtain better refrigeration effect.