CO2 Capture by Absorption with Potassium Carbonate

Abstract

Several process improvements have recently been incorporated into this Hot Potassium Carbonate process for CO2 removal. The influence of steel surface condition and solution chemistry on the critical inhibitor concentration required for spontaneous passivation of carbon steel in typical solutions of hot potassium carbonate plant (HPC) was studied. V2O5 solution was used as an inhibitor. It was found that the critical inhibitor concentration depended on solution composition and the steel surface condition. An inhibitor concentration of 14-15 g/l required to ensure spontaneous passivation under all conditions. A minimum level of V+5 ions is required for inhibition, so that monitoring the V+5 concentrations above 30% of total vanadium crucial to successfully managing corrosion protection in plant.