Increased extraction with modified seawater
In our research, we test a variety of seawater modifications for injection, particularly investigating desalination and sulphate removal. These compositional changes alter the interaction between water, oil and rock, ultimately providing improved recovery.
In laboratory tests with modified seawater we can extract around 4% more oil, and we continue to develop this work to confirm applicability at large industrial scale.
Reduced corrosion and chemical consumption
A major effect of using injection water containing less sulphate is that less hydrogen sulphide (H2S) is formed in the reservoir, which provides a number of environmental benefits. H2S is a toxic gas and can lead to increased corrosion and scaling, but the modified water injection helps to mitigate against these effects. The bacteria that form H2S do not get the same amount of sulphate as before, and thus their growth conditions are weakened. These modifications help to increase the service life of current infrastructure and thus lower operating costs. Simultaneously, reductions in H2S in the reservoir allow a reduction of the use of other chemicals normally used to remove the gas later in production.
Less CO2 per oil barrel
The increased recovery means that we get more production for the energy used to pump water into the reservoir. In other words, advanced water injection is more energy efficient than conventional water injection, and thus our research contributes to reducing the amount of CO2 emitted per oil barrel produced.
Modelling of fractures
Another part of our research is concerned with creating models that show the distribution of fractures in the reservoir and their influence on fluid flow through geological layers. By gaining a better understanding of the properties of the rock we can further optimize the recovery with modified water. We have already released a solution for single layer geological modelling, the DFN Generator software, as open source and are currently working on adding a multi-layer function.
Our research into advanced water injection is done in close collaboration with DUC, creating many synergies. The design of DUC's platforms makes it relatively straightforward to implement our results, as there is already room for the relatively inexpensive water treatment plants that would be installed on the platforms. The collaboration with DUC thus means that DUC would be able to obtain the energy benefits and at the same time have a positive economic effect from the research results.