Safety aspects of the use of ammonia and an ammonia-hydrogen mixture

Abstract

Ammonia is a well-established raw material in the chemical industry. Among others, it is used to produce fertilisers, synthetic fibres or drugs. Ammonia is also used as a refrigerant, and it is viewed as a future fuel in the power industry. Technologies for its combustion in a mixture with hydrogen or methane (natural gas) are also being developed. The widespread use of ammonia involves the need for its transportation and storage. Both these processes are affected by its physical and chemical properties because ammonia is a toxic and flammable substance. The paper presents an analysis of the hazards posed by an uncontrolled leakage of ammonia and its mixture with hydrogen from a 10 m3 tank. The range of hazard zones due to the toxic effects of ammonia is a few dozen metres. In the case of ammonia-hydrogen mixtures, a fire hazard appears, and the range of hazard zones due to thermal radiation is several metres. The total risk presented by an uncontrolled release of ammonia-hydrogen mixtures stored in 10 m3 tanks is 107 and occurs in an area of up to 40 m.