Discussion on the fire hazard classification of liquid ammonia distillation units
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Currently, I have come across a facility that produces electronic-grade liquid ammonia, which involves the distillation of liquid ammonia. Ammonia gas is classified as Category B gas under petrochemical regulations, while liquid ammonia is classified as Category BA liquid under those same regulations. According to the Comprehensive Book on Hazardous Chemicals, the flash point of ammonia is -54°C; no information regarding the flash point of liquid ammonia was found. According to Article 1 of Petrochemical Regulation 3.0.2, does the liquid ammonia distillation process require upgrading to a Class A facility?
3.0.2 The fire hazard classification of liquefied hydrocarbons and flammable liquids shall be carried out in accordance with Table 3.0.2, and the following provisions shall be met: 1 Liquids of Category B whose operating temperature exceeds their flash point shall be regarded as Category A B liquids； Does liquid ammonia distillation meet the first criterion?
According to Baidu, the flash point of liquid ammonia is said to be 11°C
What temperature is reached in liquid ammonia distillation? Above the flash point?
According to the classification of fire hazards, liquid ammonia belongs to Category A2 liquids, with a flash point ranging from 28 to 45 degrees. Therefore, if the distillation temperature is above 45, it falls under Category A B.
The other design documents seen so far define it as Category B; it is currently designated as a Category B device. Regarding this issue, a counterquestion was raised: if a device is classified as Category A because its operating temperature exceeds its flash point, should liquid ammonia storage areas also be classified as Category A? In reality, however, liquid ammonia storage areas are classified as Category B. https://mp.wei*n.qq.com/s/IeXaKLgzXJgyGzpdDp3P5A