Kraus reaction hydrogen sulfide conversion rate
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Klaus process for sulfur recovery: what are the conversion rates of hydrogen sulfide in the first, second, and third converters respectively?
Under normal conditions, the conversion rate in the reaction furnace of the sulfur recovery unit is around 70%; the conversion rate in the first reactor is approximately 20%, while that in the second reactor is about 5%. If there is a third reactor, the conversion rate is around 2-3%. Therefore, without exhaust gas treatment, the maximum conversion rate that can be achieved is 97-98%.
Industrial practice has shown that at the high temperatures achievable in combustion furnaces, the H2S conversion rate inside the furnace can generally reach 60–75%. With a two-stage Claus process, the overall sulfur recovery rate of the plant is about 92–95%, while with a three-stage Claus process, this rate can reach up to 98%； If an exhaust gas treatment system using the reduction absorption method is further added to the secondary Claus unit, the overall sulfur recovery rate of the entire system can reach over 99.8%.
When designing, the conversion efficiency of each converter stage is generally set at around 85%; by taking into account the conversion efficiency in the thermal reaction section, one can calculate the conversion efficiency for each converter stage.
Sulfur recovery technology, recovery rate: Two-stage Claus catalysis – 96.0–97.0%; Three-stage Claus catalysis – 97.0–98.0%; Two-stage Claus catalysis + free sulfur release – 99.0–99.2%; Three-stage Claus catalysis + free sulfur release – 99.2–99.5%; Two-stage Claus catalysis + hydrogenation – 99.5–99.7%; Two-stage Claus catalysis + sulfur oxidation release – 99.8–99.9%; Two-stage Claus catalysis + exhaust gas treatment (existing regeneration unit) – 99.8–99.9+; Two-stage Claus catalysis + exhaust gas treatment (including regenerated Claus injection) – 99.8–99.9+; Free-jet Claus process – 100