Modelling and Experimental Study of SO2 Removal and NH3 Recycling in an Ammonia Based CO2 Capture Process

Abstract The high NH 3 loss to the gas stream (NH 3 slip) is one of the major issues in the ammonia based CO 2 capture technology. Meanwhile, the removal of sulphur dioxide pollutant (SO 2 ) from flue gas is a prerequisite for many CO 2 capture processes. Flue gas desulphurization (FGD) is not installed in Australian power plants and significant capital/investment costs are required to install FGD. In this study, we proposed an advanced process configuration to combine SO 2 removal and NH 3 recycling in one process development and solve these two problems together. A rate-based model for the system of NH 3 -CO 2 -SO 2 -H 2 O was established and employed to simulate the process flow sheet. The temperature, pH and N/S ratio profile, SO 2 removal and NH 3 recycling efficiency along the column were analysed. Experimental work using a bubble column was carried out to provide an initial test on the technical feasibility of the SO 2 and NH 3 absorption process. Both the modelling and experimental results suggest that the proposed process results in excellent removal and recovery of SO 2 and NH 3 .