Calculation of a packed column for absorption of hydrogen sulfur from gases formed by separation of crude oil

Volgograd State Technical University, 28 Lenin avenue, Volgograd, 400005, Russia

^* Corresponding author: pahp@vstu.ru

Abstract

According to the well-known calculating algorithm for the packed absorption column, the main technological parameters and geometric dimensions of the apparatus for hydrogen sulfide containing gases, formed during the separation of crude oil, are determined. A 2,5-n solution of monoethanolamine is selected as the absorbent. Comparative results of the calculations are showing, that the working pressure in the column should be 4 atm, since with their lower values, the flow rate of the absorbent and the size of the column are increasing. The increase in working pressure is impractical, since it will require a transition from centrifugal and compresses pumps to piston pumps. ∏ The obtained parameters were compared for an absorption column in which the flow structure of the gas and liquid phases corresponds to ideal displacement, with the calculation results when the flow structure in the gas phase corresponds to the ideal displacement mode (as in the standard calculation algorithm) and in the liquid phase to ideal mixing. It is shown that, with the Peclet number of longitudinal diffusion p_e<40 the height and volume of the column increases by 10 and more percent and should be taken into account when packed columns, intended for absorption processes, are designed. At p_e=30 the height and volume of the nozzle in the column increases by 27%. Another feature of the modelling and calculation of devices is a spike in concentration, meaning, that the lower part of the working line will cross the equilibrium. Calculations in thisparticular case show that at ≈ 11 the working line crosses the equilibrium and theoretically column height and volume →∞.