Real time production monitoring with prediction and validation

Abstract

This Master of Science studies Optimum Online’s real time estimated production at the Ekofisk Field. Information from offshore process sensors are used to validate the individual well estimates and to detect any deviation in a wells performance. In order to ensure the quality of the estimated production, a temperature verification is used by monitoring the differences between the calculated temperature in the simulations and the measured temperature at the wellhead. An accepted limit in deviations determines if the production is verified or not. Solutions for improvement of estimates during an unverified period are suggested, depending on what cause the change in well behaviour. Upstream and downstream choke pressures, and choke size are used to predict a flowrate through choke. The flowrate is compared to Optimum Online real-time estimates and to welltests. The aim is to find an expression of a predicted flow rate that is a function of the pressure drop and may detect a decline in production. The flowrate will be thoroughly examined before implemented and tested in Optimum off line version and checked for verification.