Advanced simulation of H2S scavenging process with triazine at different depths of gas well

Over the 10 years the world has experienced significant growth in global natural gas consumption, rendering natural gas as one of the most important energy sources of the future. However, more than 40% of the natural gas reservoirs are sub quality because of the presence of acid gases like hydrogen sulfide (H2S) and carbon dioxide (CO2). Removal of these impurities from natural gas is of prime importance because of the health, environment, and corrosion issues in pipelines and other processing equipment. Absorption of H2S by 1,3,5-tri( 2-hydroxyethyl)-hexahydro-s-triazine has many advantages in terms of economics and efficiency over alkanolamines. The main objective of this work is to develop a Visual Basic simulation for hydrogen sulfide removal from natural gas at different depths of gas well using triazine. The thermodynamic properties of the components, triazine, thiadiazine, and diathiazine estimated from the Aspen Plus (R) have closer agreement with Spartan simulation results. H2S concentration in the clean gas and the triazine requirement per pound of H2S removal at different depths along the well obtained from the Visual Basic simulation were validated with the Coastal Chemical Inc., field data. With the increase in mass flowrate of triazine solution, the H2S concentration in the clean gas decreased, and the amount of triazine required per pound of H2S removal decreased. The developed simulation calculates the quantity of triazine required per pound of H2S removal at different depths of the gas well, which allows the user to determine the optimum depth for maximum H2S removal with minimum triazine requirement.