Jespersen, Stefan

PhD Student Stefan Jespersen

PROJECT TITLE: Optimal Control of De-Oiling Hydrocyclones Based On Online Oil-in-Water Sensor Fusion

PhD period: 2020.08.01 – 2023.07.31.
Section: Esbjerg Energy Section
Research Programme: Offshore Energy Systems
Supervisor: Zhenyu Yang
Co-Supervisor: Petar Durdevic Løhndorf
Contact Information

Funding: Danish Hydrocarbon Research and Technology Center (DHRTC)


Oil & gas will remain an important energy source during the transition towards more sustainable alternatives. Through this transition it is important to reduce the impact of oil & gas on the environment. Produced water which is waste water from the oil & gas production needs to be handled in order not to damage the marine life.

In the North Sea the current concentration limit on dispersed oil in the produced water is 30 mg/L. As the oil & gas reservoirs mature, the amount of produced water increase, which leads to an increased amount of oil being discharged, if the concentration is not reduced. Some operators choose to re-inject the produced water into the reservoir but residual oil in the injection water can lead to production issues.

Hydrocyclones are often utilized for removing residual oil from the produced water, due to their simplicity and low cost. The current operation of de-oiling hydrocyclones is based on a ratio of pressure drops (PDR) to control the flow split in the hydrocyclone. Some operators use online Oil-in-Water (OiW) monitors for reporting, but not directly for feedback control.

This project investigates the possibility of combining measurements from OiW monitors and use the measurement to increase the separation efficiency through feedback control.


Publications in journals and conference papers may be found at VBN.