The water scrubbing of biogas is an efficient, cheap and environmental friendly process to remove CO2 from biogas in order to upgrade it into biomethane. This work deals with the modelling and simulations of a scrubber-flash-stripper high pressure water scrubbing process, which is currently the most mature technology. The model and its associated simulation procedure can be used to estimate appropriate device sizes as well as to assess the performance of a given plant. Thanks to this tool, an optimized configuration is computed for a reference case. A sensitivity analysis is also realized in term of scrubbing efficiency and CH4 slippage. The influence of parameters related to the water recycling as well as the operating parameters is investigated. Moreover, the sensitivity of the model with respect to the solubility and transfer coefficient parameters is analyzed, in order to gain insight on the parameter to focus in the framework of a model calibration by experimental results. (C) 2017 Elsevier Ltd. All rights reserved.