Ammonia flammable range

Liquid aiiliydrous ammonia has a large coefficient of expansion, wliich could lead to serious problems during storage and transfer due to tlie hydrostatic pressure exerted by the liquid. The flammability range of ammonia in air at atmospheric pressure is from 16 to 25% ammonia by volume. Increasing tlie temperature mid pressure of the ammonia broadens tlie flammability range. Ammonia is readily absorbed in water to make ammonia liquor (ammonimn... 

The disadvantage are toxicity and flammability. Ammonia has a corrosive effect on tissues and can cause laryngeal, bronchial spasm and edema, which lead to obstructed breathing. Ammonia s flammability range in air is 16-25% by volume. It is usually characterized as hard to ignite (71). A suitable ammonia detection system with alarm should be installed and well maintained. Detectors should sound an alarm at the lowest practical level, not to exceed 1000 ppm. 

Dimethylamine, (CH3)2NH, an amine hydrocarbon derivative, is a gas with an ammonia-like odor. It is a dangerous fire risk, with a flammable range of 2.8 to 14% in air. It is insoluble in water. The vapor density is 1.55, which is heavier than air. The boiling point is 44°F, and the ignition temperature is 806°F. Dimethylamine is an irritant, with a TLV of 10 ppm in air. The four-digit UN identification number is 1032. The NFPA 704 designation is health 3, flammability 4, and reactivity 0. The... 

They are very soluble in water, alcohols, ethers, and most polar solvents. At low temperatures, aqueous methylamines form crystalline hydrates CH3NH2-3H20, (CH3)2NH 7H2O, and (CH3)3N IOH2O. In the presence of ammonia, methylamines react explosively with mercury so instruments containing mercury should not be used on methylamines. The amines also are flammable in air. Their flammability ranges as well as some of their important physical properties are listed in Tables 28.16 and 28.17. 

As mentioned, RMP addresses specific chemicals/materials (compounds) it addresses the accidental release of over one hundred chemical substances. Of the RMP chemicals listed, seventy-seven include acutely toxic chemical compounds and sixty-three flammable gases. Threshold quantity levels range from 500 pounds to 20,000 pounds. USEPA estimates that approximately 100,000+ sources are covered by the rule. The universe includes chemical and most other manufacturers, certain wholesalers and retailers, drinking-water systems, wastewater treatment works, ammonia refrigeration systems, chemical wholesalers and end users, utilities, propane retailers, and federal facilities. 

Ammonia vapor is slightly flammable (NFPA rating = 1) and ignites only with difficulty. Ammonia forms explosive mixtures with air in the range 16 to 25%. 

Although ammonia is flammable in air only within the narrow range of 16 percent to 25 percent by volume, the mixture of oil with ammonia broadens this range. Therefore, precautions are necessary to keep sources of flame or sparks from areas that involve ammonia storage or use. 

The feed gas of ammonia oxidation is a mixture of NH3 with air and contains, typically, 11 vol.% NH3 (the lower flammability limit is 15% at 20 °C). The gas velocity (empty reactor) under reaction conditions (mean gas temperature 600 °C) is in the range 0.7-1.3ms for low- and medium-pressure processes (1-4 bar) and up to 3 m s for high-pressure processes (8-12bar) (Holzmann, 1967). Thus, the residence time (empty reactor) is about 0.2-0.6 ms, if we take the number of gauzes N (3 for 1 bar and 30 for a high pressure of around 10 bar) and the diameter of the wire d (typically 60 p,m) as basis for the reactor length I at = Nd (that is, only the space taken up by the catalyst is counted). 

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