METHOD FOR PRODUCTION OF ELEMENTARY SULFUR FROM EMISSION GASES CONTAINING SULFUR DIOXIDE Russian patent published in 2004 - IPC

FIELD: inorganic compounds technology. SUBSTANCE: invention relates to production of elementary sulfur from nonferrous metallurgy gases containing largely nitrogen and sulfur dioxide. Method comprises cooling metallurgical sulfur dioxide, dedusting, concentrating sulfur dioxide by complete or partial liquefaction thereof followed by heating-mediated vaporization, enrichment with oxygen to specified concentration, reduction with hydrocarbon gas at elevated temperature followed by cooling of products and condensation of elementary sulfur obtained. Reduced gas is heated by mixing it with products of combustion of hydrocarbon fuel in oxygen-containing gas and then subjected to catalytic processing in at least two steps of catalytic conversion with final condensation of resulting sulfur and afterburning of toxic combustible sulfur compounds in tail gas into sulfur dioxide. In this process, vaporization of liquefied sulfur dioxide is effected by indirect heat exchange due to cooling heat of gas leaving first stage of catalytic conversion carried out at 400-600 C, which is cooled to temperatures of the second catalytic conversion equal to 230-260 C. In addition, heating of reduced gas before the first catalytic step is accomplished by mixing hydrocarbon fuel with combustion products in oxygen-containing gas in molar ratio constituting 0.5-1.0 stoichiometric ratio. In this case, ratio of summary concentration of carbon monoxide and hydrogen to concentration of sulfur dioxide at the inlet to the first step of catalytic conversion is more than 2. EFFECT: reduced specific consumption of reducing agent and reduced process expenses. 2 cl, 1 dwg, 2 ex