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Annual Report 2015
Coalescence
(merging
between particles, oil
drops or similar in a
hydrocarbon
flow)
is
crucial for separation
and transport of hydro-
carbons. The main ob-
jective of the project is to
obtain a new semi-em-
pirical expression of coa
lescence time (time for two particles to merge).
Coalescence time in general is an important
Modelling of coalescence
Project Manager,
Associate Prof. Brian
Grimes
Postdoc, Aleksandar
Mehandzhiyski
equation in both simple and complex separation
and transport models. With a new expression for
the coalescence time, the effects of petro-sur-
factant chemistry can be taken into account. To
wit a molecular dynamics, simulations will be
performed to capture the molecular effects and to
obtain a relation with a film drainage model via an
expression for the disjoining pressure. Thus, the
project employs multiscale modelling in order to
solve more accurately a problem on the process
scale, namely the coalescence and separation of
water and oil.
SEPARATION PROCESS CONCEPTS
One of the goals of subsea processing is to reduce the need for topside processing and for some fields to
move all the needed gas and liquid processing subsea. The first case, partial subsea processing, could
be a concept where the gas is treated to pipeline specifications directly and the further oil stabilization
and chemical treatment is handled on a floater or platform (which may be an existing installation). Such
a system will unload the topside gas processing making tie-back of new discoveries possible and also
make long distance gas transport possible.
The process equipment used topside today, like different absorbers for water and sour gases are not
suitable for subsea application. There is need for developing new contacting devices that are not based
on gravity and without rotating parts. Additionally they should be compact and have high reliability. The
objective is thus to establish new separation equipment and concepts capable of running over long time
intervals without maintenance or intervention. In the first three years of SUBPRO, the focus is on following concepts:
- Membrane dehydration process
- Combined H
2
S and hydrate control
- Compact subsea separation concepts (liquid-liquid separation)
The development of process concepts is supported by fundamental modelling and experimental investigations of fluid particle
breakage.
Research area manager,
Associate Prof. Hanna
Knuutila