Experimental Study and Modeling of H2S Absorber in Sulfiran Process

Document Type : Research Paper

Abstract

In this paper the desulphurization of gas streams by using aqueous ferric chelate solutions as washing liquor is studied mathematically and experimentally. The desulphurization is accomplished by a precipitation reaction that occurs when sulfide and ferric ions are brought into contact with each other. The absorption experiments of H2S in aqueous ferric chelate solutions were carried out in a packed-bed scrubber. The experiments were conducted in different operating conditions (gas flow rate: 2.2-4.1 lit/min, ferric chelate flow rate: 0.2-2.0 lit/min, hydrogen sulfide concentration: 130-230 ppm and packing height: 0.3-0.3 m). A dynamic mathematical model was used to predict the removal efficiency of the packed-bed scrubber for H2S absorption into a ferric chelate solution. From mass balances in the scrubber, a set of partial differential equations, relating the species concentrations in the gas and liquid phases, along the axial direction in the scrubber were formulated. These relationships were numerically solved to give performance profiles. The validity of the model was examined by comparing the results of the model with our experimental data. The predicted results of the model are in good agreement with the experimental data obtained in different operating conditions.

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منابع
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