Hydrogen and sulfur recovery from hydrogen sulfide wastes
AssigneeThe University of Chicago
InventorsJohn B. L. Harkness, Anthony J. Gorski, Edward J. Daniels
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Abstract
A process for generating hydrogen and elemental sulfur from hydrogen sulfide waste in which the hydrogen sulfide is associated under plasma conditions and a portion of the hydrogen output is used in a catalytic reduction unit to convert sulfur-containing impurities to hydrogen sulfide for recycle, the process also including the addition of an ionizing gas such as argon to initiate the plasma reaction at lower energy, a preheater for the input to the reactor and an internal adjustable choke in the reactor for enhanced coupling with the microwave energy input.
Claims21
A process for treating a gas stream which contains CO.sub.2 and water and sulfur-containing compounds including hydrogen sulfide, comprising the steps of feeding the gas stream containing hydrogen sulfide to a plasma reactor for dissociating hydrogen sulfide under plasma conditions with RF energy to provide a product stream including hydrogen, sulfur, sulfur-containing compounds comprising one or more of COS, CS.sub.2 or SO.sub.2 and non-sulfur containing compounds, said plasma reactor being operated at a temperature in the range of from about 150.degree. C. to about 450.degree. C. and at a pressure in the range of from about 0.5 to about 2 atm, feeding the product stream to a sulfur recovery unit to remove essentially all of the sulfur therefrom leaving an overhead gaseous stream of hydrogen, unconverted H.sub.2 S, sulfur-containing and non-sulfur-containing compounds and a sulfur aerosol, feeding the overhead gaseous stream to a catalytic reduction unit for reacting the sulfur-containing compounds and sulfur aerosol with hydrogen in the overhead gaseous stream in the presence of a catalyst to form a hydrogen sulfide enhanced stream and to decrease the concentrations of sulfur-containing compounds and non-sulfur containing compounds, compressing the hydrogen sulfide enhanced stream, and subsequently separating hydrogen and hydrogen sulfide as final product streams.
The process of claim including a step of preheating the hydrogen sulfide stream fed to the plasma reactor.
A process for treating a gas stream which contains CO.sub.2 and water and sulfur-containing compounds including hydrogen sulfide, comprising the steps of feeding the gas stream containing hydrogen sulfide and hydrogen to a plasma reactor for dissociating hydrogen sulfide under plasma conditions with RF energy to provide a heated product stream including hydrogen, sulfur, sulfur-containing compounds and non-sulfur-containing compounds, said plasma reactor being operated at a temperature in the range of from about 150.degree. C. to about 450.degree. C. and at a pressure in the range of from about 0.5 to about 2 atm, passing the heated product stream in heat exchange relationship with the gas stream prior to feeding the gas stream to the plasma reactor, thereby to heat the gas stream and cool the product stream, feeding the cooled product stream to a sulfur recovery unit to remove essentially all of the sulfur therefrom leaving an overhead gaseous stream of hydrogen, unconverted H.sub.2 S, sulfur-containing compounds comprising one or more of COS, CS.sub.2 or SO.sub.2 and non-sulfur-containing compounds and a sulfur aerosol, feeding the overhead gaseous stream to a catalytic reduction unit for reacting the sulfur-containing compounds and sulfur aerosol with hydrogen in the overhead gaseous stream in the presence of a catalyst to form a hydrogen sulfide enhanced stream and to decrease the concentrations of sulfur-containing compounds and non-sulfur containing compounds, compressing the hydrogen sulfide enhanced stream, and subsequently separating hydrogen and hydrogen sulfide as final product streams.
A process for treating a gas stream which contains CO.sub.2 and water and sulfur-containing compounds including hydrogen sulfide, comprising the steps of feeding the gas stream containing hydrogen sulfide along with hydrogen and an ionizing gas selected from one or more of helium, argon, or krypton in the range of from about 0.01% to abut 10% by volume of the gas stream to plasma reactor for dissociating hydrogen sulfide under plasma conditions with RF energy to provide a heated product stream including hydrogen, sulfur, sulfur-containing compounds comprising one or more of COS, CS.sub.2 or SO.sub.2, non-sulfur containing compounds and ionizing gas, passing the heated product stream in heat exchange relationship with the gas stream prior to feeding the gas stream to the plasma reactor, thereby to heat the gas stream and cool the product stream, feeding the cooled product stream to a sulfur recovery unit to remove essentially all of the sulfur therefrom leaving an overhead gaseous stream of hydrogen, unconverted H.sub.2 S, sulfur-containing and non-sulfur-containing compounds and a sulfur aerosol, feeding the overhead gaseous stream to a catalytic reduction unit for reacting the sulfur-containing compounds and sulfur aerosol with hydrogen in the overhead gaseous stream in the presence of a catalyst to form a hydrogen sulfide enhanced stream and to decrease the concentrations of sulfur-containing and non-sulfur containing compounds, compressing the hydrogen sulfide enhanced stream, separating hydrogen and hydrogen sulfide plus the ionizing gas as final product streams, and recycling the hydrogen sulfide and the ionizing gas to the gas stream before feeding same to the plasma reactor, wherein the plasma reactor is operated at a temperature in the range of from about 150.degree. C. to about 450.degree. C. and at a pressure in the range of from about 0.5 to about 2 atm, the sulfur recovery unit is operated at a temperature in the range of from about 120.degree. C. and at a pressure in the range of from about 0.5 atm to about 2 atm, and the catalytic reduction unit is operated at a temperature in the range of from about 120.degree. C. to about 250.degree. C. and at a pressure in the range of from about 0.5 atm to about 2 atm.
Dependencies are inferred from the claim text.