The DHRTC’s research programme
“BaSO4 deposits on the horizontal pipes
Another common integrity problem in
is using the best practise of the
and needs to be removed mechanically.
the oil and gas industry is corrosion,
manufacturing industry, e.g.
It’s an expensive operation, so if you
which reduces the lifetime of oilfield
modularisation, which helps reduce the
can avoid BaSO4 deposits to begin with,
equipment.
complexity of a process or operation
then that’s an area where you can really
by splitting it into smaller units, or
cut expenses,” said Karen Feilberg,
modules.
Senior Researcher at DTU and in charge
“We try to find the best of breed. We
of the Scale project.
“It affects production because you need to replace the production tubing, or part of a pipeline. This is a costly operation, also the production downtime, so
look at different maintenance operations
CaCO3 is formed primarily in the upper,
obviously you want to be better at
and see if we can identify ways to
vertical part of the well and may also
predicting the corrosion rate to plan
reduce the time spend on the individual
prevent the sub-surface safety valve
maintenance operations better,” said
operations,” said Kitt Ravnkilde.
from closing properly if an incident
Kitt Ravnkilde.
The better you can predict when you
should happen.
To predict scale and corrosion requires
need to do maintenance work, the better
The focus of the research programme
the right tools and one such tool is a new
you can plan. Something as seemingly
is to understand the mechanisms and
software programme developed by its
simple as available beds on the platform
kinetics of scale formation and predict
partner, Aalborg University.
can be a big problem.
the operating conditions that cause the
“When changing a tubing, for example, you need beds for maintenance people
various types of scales to be formed and where in the well the scales are located.
“We’re hoping to develop a riskbased well intervention planning tool, a software programme, which
for several days. If it’s a sudden
“This will help to predict and carefully
takes all risks and uncertainties into
integrity problem in a well, that means
plan appropriate treatments, which
consideration,” said Kitt Ravnkilde.
production downtime, perhaps for a very
would mitigate scale formation or
long time, a new rig needs to be found,
remove scale deposits. Subsequently,
people are sent home and maintenance
it will result in reduced operating
staff transported to the platform,” said
expenditures as well as increased oil
Kitt Ravnkilde.
recovery and extended lifetime of the wells, facilities and pipelines,” said Kitt Ravnkilde.
Scale & Corrosion The researchers are also looking to reduce costs by solving scale and corrosion challenges in wells in a collaboration with Aarhus University. “We’re looking at scale deposits and corrosion in the injection and production wells. It’s cost-heavy to do maintenance activities in wells if there’s corrosion but also to have scale deposits removed,” said Kitt Ravnkilde. Scale such as Calcium Carbonate (CaCO3) and Barium Sulfate (BaSO4) will deposit inside the tubing wall and over time build up and almost choke production.
Kitt Ravnkilde, Principal Programme Manager at DHRTC.
Energy Insight Yearbook 47