2021 begins with newly added projects to two of DHRTC’s research programmes. DHRTC has approved four new projects within the Produced Water Management programme – a research programme focused on reducing the environmental footprint associated with oil and gas production in the Danish North Sea.
The Centre has also chosen to provide funding for further development of the Multilevel Flow Modelling (MFM) technology, which is the main part of the programme Operations and Maintenance Technology. The new projects must be seen in context with DHRTC’s increased focus on reducing the environmental footprint of oil and gas production.
Reinjection of Produced Water
The Produced Water Management Programme at DHRTC issued a call for research proposals in September 2020 within the theme Reinjection of Produced Water (PWRI). We received 20 proposals in the call, and have now completed the screening process. Four projects were approved, of which two will initially be conducted as feasibility studies to prove the technology concept and mature it to technology readiness level TRL1.
In some oil fields, water is injected into the reservoir to increase oil production. While the injected water helps to increase depleted pressure within the reservoir, it also helps to move the oil towards producing wells. The injected water is typically seawater. Our research will focus on enabling produced water to be reinjected into the reservoir. Reinjection of produced water alone will not provide sufficient injection volume to replace the combined volume of produced oil, gas and water volume (full voidage replacement) since water is only one of the fractions of produced fluids. Hence, seawater has to be added to the injection stream. Mixing seawater and produced water generates a complex mixture that is very challenging to manage from a well and reservoir aspect. With these research projects, we will be addressing two key challenges related to mixed water injection.
The first key challenge we will address is scaling in the process facilities and wells, and the formation of skin at the well contact and near-wellbore area caused by build-up of so-called “schmoo”, which is a thick substance consisting of various particles (suspended solids and scale particles – Iron sulphide, Carbonates and Sulphates), oily components, biological mass and residual production chemicals. We will study the effects of continuous addition of acid in ultra-low concentrations to prevent scaling and “schmoo” formation. We will also develop a low cost method for continuous production of acid on site to supply the acid that needs to be added to the injection water for continuous de-scaling.
The second key challenge we will address is the control of oxygen (O2) in the injection water. Oxygen promotes corrosion and bacterial activity. We will attempt to develop a new metal-oxide framework to scavenge oxygen. This technology will replace the use of oxygen scavenger chemicals and aid the mechanical oxygen removal equipment (such as vacuum towers) on site to ensure full removal of oxygen from the injection water.
Further development of Multilevel Flow Modelling technology
DTU Electrical Engineering, Total E&P, Kairos Technology, and DHRTC have had great success in developing a new software application to provide real time decision support to control room operators. The software employs Multilevel Flow Modelling (MFM) theory to visualize the root cause of disturbances and upsets in the process facilities. This Control Room Assistant prototype successfully passed technology readiness level TRL4 in November 2020.
The Centre have now decided to fund further development of the MFM technology. The next phase of the project will be in collaboration with DTU Electrical Engineering and DTU Mechanical Engineering. Kairos Technology will collaborate to develop software solutions based on the extended MFM functionality, and Total E&P will provide support and data to the project.
The new functionality will allow integration of control system functions into the MFM framework, as well as abnormal flow conditions, such as reverse flow, pressure relief scenarios, etc. We will also integrate with equipment maintenance data and condition monitoring to support condition-based maintenance through mechanical failure prediction in the MFM framework.
Kairos Technology will develop a software that improves process safety by assisting the HAZOP process when designing process facilities. This means improved quality control and the ability to run what-if analyses through simulating various situations quickly. With an established model, it will be easy to rerun the HAZOP when engineering modifications to the process. It will also provide increased operator assistance when in operation, by giving control room operators an improved tool for managing abnormal process conditions.
The HAZOP assistant development will also receive funding from the Norwegian Innovation Fund (Innovasjon Norge) and ConocoPhillips as operator of the Greater Ekofisk Area in the Norwegian sector, where Total E&P is the majority partner.