Abstract:
Multiphase flow is the simultaneous flow of two or several phases through a
system such as a pipe. This common phenomenon can be found in the
petroleum and chemical engineering industrial fields. Transport of sand particles
in multiphase production has attracted considerable attention given sand
production is a common problem especially to the oil and gas industry. The
sand production causes loss of pipe wall thickness which can lead to expensive
failures and loss of production time. Build-up of sand in the system can result in
blockage and further hamper production. Monitoring of multiphase flow is a
process that has been established over several decades.
This thesis reports an assessment of the application of Acoustic Emission (AE)
technology as an alternative online technique to monitoring of sand particles
under multiphase flow conditions in a horizontal pipe. The research was
conducted on a purpose built test rig with the purpose of establishing a relation
between AE activity and sand concentration under different multiphase flow
conditions.
The investigation consisted of five experimental tests. The initial experiment
was performed to provide a basis for the application of AE technology to detect
sand particle impact prior to performing tests in multiphase flow conditions.
Further investigations are reported on two phase air-sand, water-sand and air-
water-sand three-phase flows in a horizontal pipe for different superficial gas
velocities (VSG), superficial liquid velocities (VSL) and sand concentrations (SC).
The experimental findings clearly showed a correlation exists between AE
energy levels and multiphase flow parameters, such as superficial liquid velocity
(VSL), superficial gas velocity (VSG), sand concentration and sand minimum
transport condition (MTC).
