Natural gas processing plants are an essential part of the energy industry, providing clean burning fuels and valuable chemical feedstock The importance and complexity of gas processing plants have increased over the years, leading to improvements in energy efficiency and integration with petrochemical plants. These improvements are aided by the use of computer simulation models as tools for designing, troubleshooting, and optimizing gas treating plants. This work discusses the major optimization techniques based on the Benfield HiPure process at Abu Dhabi Gas Liquefaction Company Limited (ADGAS) and the use of a process simulation tool, ProMax (R). At ADGAS' Train 3 plant in Das Island, high pressure natural gas containing 6 to 7 mol %acid gas first comes into contact with a 30 wt. %Potassium carbonate (K2CO3) solution promoted with 3 wt. % diethanolamine (DEA). The gas is then contacted with a 20 wt. % DEA solution downstream. The results from the simulations show a close match with the plant operating data. The simulation model was then used to explore the effect of changes in process parameters on ADGAS' plant performance. (C) 2014 Elsevier B.V. All rights reserved.