Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
20 words
A process according to claim 1, characterized in that said ratio of hydrogen sulfide to sulfur dioxide is about 3:1.
Claim 2
Dependent Claim
39 words
A process according to claim 1, characterized in that said gas is the exhaust gas of a Claus furnace, and the hydrogen sulfide to sulfur dioxide ratio is adjusted by a controlled supply of air to the Claus furnace.
Claim 3
Dependent Claim
40 words
A process according to claim 1, characterized in that said gas is the exhaust of a Claus furnace, and the hydrogen sulfide to sulfur dioxide ratio is adjusted by a recycling of Claus process exhaust gases to the Claus furnace.
Claim 4
Dependent Claim
30 words
A process according to claim 1, characterized in that the hydrogen sulfide to sulfur dioxide ratio is adjusted by an addition of hydrogen sulfide to the gas to be purified.
Claim 5
Dependent Claim
23 words
A process according to claim 1, characterized in that a temperature of 120*-180* C. is maintained in the first stage containing activated carbon.
Claim 6
Dependent Claim
44 words
A process according to claim 1, characterized in that oxygen is added to the gas before the second stage containing activated carbon in such a proportion that the rate at which oxygen is added is about 1.5 times the rate which is stoichiometrically required.
Claim 7
Dependent Claim
51 words
A process according to claim 1, characterized in that the reaction temperature in the second stage containing activated carbon is kept below 200* C. by withdrawing a portion of the purified gas, cooling said portion, and adding the cooled gas to the gas which leaves the first stage containing activated carbon.
Claim 8
Dependent Claim
30 words
A process according to claim 8, characterized in that purified gas is recirculated as aforesaid only to such an extent that the temperature is above the dew point of water.
Claim 9
Dependent Claim
36 words
A process according to claim 1, characterized in that inert gas which is free of oxygen, carbon dioxide and water is passed at temperatures of 350*-550* C. stages which contain sulfur-laden activated carbon for regeneration thereof.
Claim 10
Dependent Claim
16 words
A process according to claim 10, characterized in that the gas used for regeneration is nitrogen.
Claim 11
Dependent Claim
41 words
A process according to claim 10, characterized in that the regeneration of the stages containing laden activated carbon is preceded by a purging thereof with hot inert gas to remove carbon dioxide and water from the stages containing laden activated carbon.
Claim 12
Dependent Claim
19 words
A process according to claim 12, characterized in that hot inert gas at 160*-180* C. is used for purging.
Claim 13
Dependent Claim
38 words
A process according to claim 10, characterized in that the desorption gas which has left the activated carbon beds being regenerated is subjected to an indirect heat exchange with hot water at about 120*-130* C. to remove sulfur.
Claim 14
Dependent Claim
51 words
A process according to claim 1, characterized in that the desorption gas is subjected to an indirect heat exchange to remove condensable sulfur, subsequently passed through sulfur-containing activated carbon beds to remove residual sulfur from the desorption gas, and is then recycled to the stages containing activated carbon to be regenerated.