Blog

Gas, from a petroleum distillation column, has its concentration of H2S reduced from 0.03 kmol H2S/kmol of inert hydrocarbon gas to 1 per cent of this value, by scrubbing with a triethanolamine water solvent in a counter-current packed tower, operating at 300 K and at atmospheric pressure.H2S is soluble in such a solution and the equilibrium relationship may be taken as Y = 2X, where Y is kmol of H2S/kmol of inert hydrocarbon gas and X is kmol H2S/kmol of solvent.The solvent enters the tower free of H2S and at a flow rate of 0.035 kmol/m2s of tower cross section. If the flow of inert hydrocarbon gas is 0.015 kmol/m2s of tower cross section, and the overall mass transfer coefficient (times specific surface area of the packing, a) KGa = 0.04kmol/sm3 of tower cross section, calculate (a) the concentration of the H2S in the solvent leaving the tower, and; (b) the height of the packed tower. ii) In your experiment you extracted CO2 from gas using water as a solvent. However, water is a poor absorbent for CO2. Removal of CO2 is an important treatment for the cleaning of gas from oil and natural gas wells (a part of the sweetening process) and has been suggested as a method to remove this green-house gas from flue gases exhausted from power stations. Conduct a brief literature review (no longer than 4 pages, excluding references and figures) describing the method by which the removal of carbon dioxide from gas streams is conducted at an industrial scale. You should address the following issues: i) What types of solvent (or solvents) is used to extract the CO2. What is the chemistry of the extraction process. ii) What type of gas absorption apparatus is used to perform the extraction and how in the dissolved solute then removed from the solvent so the solvent may be recycled?