There is some experimental evidence that salinity altered injection water is an effective EOR method in sandstone, however the effect in carbonates and the exact mechanism is not clear. The increased oil recovery is often attributed to wettability alterations of the rock, which can be caused by exchange of positive ions with the CaCO3 or by adsorption of negatively charged ion on the rock surface. When changing the ionic composition of the water the exact conditions for precipitation of salts and fines formation have to be investigated.
The following tasks are expected to be performed
- Selection of injection fluids for core flooding experiments on chalk samples from the relevant reservoirs
- Thermodynamic modelling of multicomponent ionic systems in relation to oil recovery
- The study of salt solubilities at reservoir conditions
- Emulsion testing for water-oil-nanoparticles
Speciation calculations will be conducted for different proposed Smart Water compositions to assist with core flooding experiments with the aim to find an effective Smart Water for carbonate reservoirs.
The line-of-sight application potential of this project is to assist the screening processes of potential water based recovery methods in the Kraka, Dan, and Halfdan oil fields.
The project is funded by the Danish Hydrocarbon Research and Technology Centre (DHRTC)
Main supervisor: Kaj Thomsen (CERE, DTU – Chemical Engineering)
Co- supervisor: Karen Louise Feilberg (DHRTC)