Abstract
Clean-up operations of oil and gas wells are carried out when newly drilled wells are started up and tested for the first time. An optimal clean-up can be important for the production properties of complex wells. As the clean-up process is highly dynamic in its nature, a conventional steady state approach for simulation is of limited value.
In the current work a clean-up case study of a dual branch long horizontal well at the Åsgard field was undertaken using a commercial transient multiphase flow simulator. Eleven production zones located along the main and lateral horizontal wellbores were modelled in detail with separate zone productivities (obtained from petrophysical data analysis) and different numbers of sand screens with inflow control device (ICD) in each zone. Simulations of different clean-up scenarios were performed prior to the real operation and the results were used to plan the clean-up. The simulations supported the decision to clean-up both the lateral and the mainbore simultaneously in one operation.
The operational data from the clean-up operation were compared to the model results and valuable data for tuning of the model were obtained. After tuning a good match between the simulation results and the operational data was obtained, also quantitatively.
The study confirmed that dynamic simulations can be a useful tool to predict and understand the behaviour of a clean-up operation.
