Simulation of mercury distribution in an offshore natural gas processing platform

Abstract

In this work, the distribution of mercury in an offshore natural gas processing platform in Norway is simulated, and the results are compared to field measurements regarding elemental and total mercury concentration in process fluids. The effect of a possible reaction between mercury and H2S that leads to solid β-HgS formation is also examined. For the simulation, the UMR-PRU group-contribution equation of state (EoS) and the SRK cubic EoS are employed, which have been extended to mercury mixtures in our previous works. The results show that both models satisfactorily predict mercury concentration in process gases, while they overpredict mercury concentration in condensates as compared to the field measurements. When the reaction is also considered, the predicted mercury concentrations in condensates are closer to the measured values. Overall, it is concluded that both models can satisfactorily predict the distribution of mercury in a gas processing plant.