1 August 2014
I am currently studying for an MSci at University of Bristol which includes a Year in Industry placement. This year I have been employed by Schlumberger Limited, an oilfield services company, at the Schlumberger Gould Research (SGR) facility in Cambridge.
Until I experienced what research was like, I was not entirely sure what it entailed. This year however, has taught me to become more patient and tenacious and I understand now that science doesn’t happen overnight – it requires dedication and planning.
I have been working in the Advanced Recovery Programme investigating the use of polymers in enhanced oil recovery (EOR). After primary and secondary oil recovery processes, 60% of the original oil can still remain in place, in large part trapped in the reservoir by capillary forces as ganglia. EOR can increase the amount of oil recovered by using thermal, gas, microbial or chemical processes. The work I am involved with has focussed on the use of polymer formulations used in chemical EOR to mobilise the remaining trapped oil.
The process of how polymers flow through porous media and thus mobilise oil ganglia is of great interest to the industry. Direct observation of the flow of fluids inside reservoir rocks, whilst possible is not generally applicable to these problems, so a 2D analogue is used instead in the form of a micromodel. Micromodels are transparent microfluidic models etched with a design that represents a simplified network of the complex pore structure found within a rock.
Polymer solutions are pumped through the models at different flow rates with varying compositions, and the flow can be observed optically. Flow visualisation involves seeding the polymer solutions with tracer colloidal particles, and then tracking the position of the particles with time using photographs taken with a high speed camera. These images can then be analysed to produce velocity field maps which allow us to quantify how the polymer flow changes with various parameters (e.g. flow or composition).
We can use this information to further investigate the multiphase situation: how the properties of polymer solutions affect the displacement of oil out of the micromodels, which is analogous to EOR in an oil reservoir. This involves initially filling the models with oil and then taking a series of photos of the displacement patterns created from a secondary flooding fluid. Using imaging processing software we can analyse these photos and calculate, for example, the percentage of oil which has been displaced out of the model. Our results will be included in a paper which will be submitted for publication in a journal.
I am very pleased to have been awarded the SCI Bristol and South West regional group prize for my presentation about my work on Colloid interface, polymer and physical at the Mike Rothwell symposium and I feel this year has left me in a position now that I can make more informed decisions about my future. Overall, I will leave my placement prepared to make the most of my final year back at the University of Bristol.
Katherine Leeper, SCI Bristol and South West Group prize winner
Schlumberger Cambridge Research