Process for purifying gases
OwnerYoshio Nogami, Isami Ooka +4inventors
InventorsYoshio Nogami, Isami Ooka, Tetsuo Hamamoto, Hirofumi Shibano, Kenji Miyao, deceased, by Mieko Miyao, legal heir
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Abstract
In purifying a gas containing at least one of hydrogen cyanide and hydrogen sulfide as a harmful component by fixing the harmful component in water as an aqueous solution of nitrogen-containing sulfur compound so as to render the gas free of the harmful component, an improvement characterized by: 1. burning the aqueous solution of nitrogen-containing sulfur compound to obtain an exhaust gas containing sulfur dioxide, 2. separating the sulfur dioxide from the exhaust gas for recovery, and 3. exhausting the gas after the separation of the sulfur dioxide.
Claims9
A method of removing HCN from a gas containing same without causing environmental pollution which comprises contacting said gas with an aqueous alkaline ammoniacal solution containing a suspension of solid sulfur to fix said HCN in said aqueous alkaline ammoniacal solution as ammonium thiocyanate, said solution having a concentration of 5 to 85% by weight of ammonium thiocyanate, burning said solution containing said ammonium thiocyanate by spraying said solution into a furnace maintained at a temperature of from 800.degree. to 1300.degree. C in the presence of oxygen in an amount of from 1.0 to 1.5 times the stoichiometric amount, said oxygen being charged into said furnace as air at least two stages thereof, to provide a sulfur dioxide containing gas essentially free of nitrogen oxides, recovering sulfur dioxide from said sulfur dioxide containing gas and exhausting the remaining gas to the atmosphere.
Dependencies are inferred from the claim text.