About the dissertation
In this thesis, a novel concept for the real-time measurement of return fluid flow rate of oil well drilling process was presented. A Venturi channel is used as a flow sensor to measure the fluid flow rate. The developed method is accurate, fast, and can measure the fluid flow rate using only two fluid level measurements from the channel.
For the estimation of the flow rate, various model-based estimators have been studied. This method is specifically useful for the conventional petroleum drilling industry.
Accurate measurements of the drilling fluid coming out of the drilling well are crucial for identifying any undesired incident such as a kick or a loss during oil drilling. These incidents can be either prevented or properly controlled by early identification. This can further reduce the risks related to incidents and can decrease the non-productive time.
Although the flow sensor has been studied with application to the oil industry, the results obtained in this Ph.D. study is generic and can be applied to other processes as well. The flow measurement concept has been successfully tested at the single-phase flow experimental facility at USN. The next step would be to test it in a pilot-scale drilling facility.
This research is a part of the project 'Semi-kidd' (sensors and models for improved kick/loss detection in drilling) which is funded by the Research Council of Norway and Equinor ASA. The project is led by USN and consists of external partners including Equinor, NTNU, Kelda Drilling Controls, Cybernetic Drilling Technologies, MHWirth, Sensor Technology, and Teknova.