Difluoromethane is a halogenated hydrocarbon (chemical formula: CH2F2), referred to as R32. It is a gas at room temperature and a colorless and transparent liquid under its own pressure. It is easily soluble in oil but hardly soluble in water. It is a refrigerant with zero ozone depletion potential. Before R32 entered the stage of history, R22 refrigerant had dominated the air-conditioning industry for decades. However, due to its greater hazard to the ozone layer, according to the Montreal Protocol and the Kyoto Protocol, the time limit for R22's withdrawal is getting closer.
Although R410A, which replaces R22 refrigerant, is not harmful to the ozone layer, to a large extent it will cause the greenhouse effect and exacerbate global warming. The greenhouse effect caused by the emission of 1 kg of R410A into the atmosphere is equivalent to the emission of 1,900 kg of carbon dioxide, and 1 kg of R32 is equivalent to the emission of 580 kg of carbon dioxide, which is less than one-third of the former.
Under such a background, R32, as a new generation of energy-saving, carbon-reducing, environmentally friendly and non-toxic refrigerant, has become a good choice on the historical stage. However, its slight flammability (international standards ISO817 and ISO5149 define the R32 safety level as A2L, which is slightly flammable, that is, except for open flames, other ignition sources can not ignite R32, and once the open flame is left, it will be automatically extinguished) under certain circumstances. Cause safety issues.