Thermodynamics of Hydrogen-Sulfide Conversion in a Claus Reactor in Coke-Oven Gas Desulfurization Circuit of MMK

Abstract

For the Claus reactor of byproduct-capture shop 2 in the coke plant at PAO Magnitogorskii Metallurgicheskii Kombinat (MMK), thermodynamic calculation of the equilibrium hydrogen-sulfide conversion at 200–350°C is undertaken, in the following conditions: total mixture pressure 1.3 atm (130 kPa); initial Claus ratio CR = [H₂S]/[SO₂] = 1.5–10.0; initial hydrogen-sulfide concentration [H₂S] = 0.3–6.5 vol %. When [H₂S] ~ 1 vol %, the direction of equilibrium conversion is reversed. Accordingly, it is expedient to limit the number of catalytic stages in the processing of hydrogen sulfide on the basis of its initial concentration. In selecting the catalyst in the Claus reactor, it is expedient to take account of the characteristics of the gas being processed and to lower the Claus ratio to the working value CR ≤ 2.