Page 452 - Handbook Of Multiphase Flow Assurance

452 12. Flow assurance modeling

Appropriate flow assurance work at this stage:
Line sizing and preliminary routing using a steady state flow tool, insulation
requirement to avoid wax/hydrate for steady state flow in early or late life.
Erosion velocity limits for mid life plateau production and for late life with increased
gas.
Identify flow assurance threats (slugging in early or late life, hydrate, asphaltene, wax,
scale, diamondoids.

3. Appraisal well is in place and flow test performed.
– More live fluids are available for tests.
– Possibly a drill stem test.
Obtain water composition, sufficient oil sample for hydrate plugging evaluation,
asphaltene deposition.
Some understanding of reservoir compartmentalization.
Limited understanding about aquifer.
Appropriate flow assurance work:
Concept evaluation.
Line sizing update, using multiphase flow models for transient analysis.
Wells placement, flowlines layout, rock consolidation which determines well ramp-up
time.
Develop several concepts with transient analysis (startup based on ramp-up for one
well, cooldown shutdown, blowdown separator sizing, slugging separator sizing.

4. Concept selection
Decide on host facility as FPSO, semi-submersible, spar, island, etc. based on country risks.
Decide on water injection program.
Decide on gas lift or boosting based on NPV of incremental fluids recovery vs. capex
and opex.
Appropriate flow assurance work:
Evaluate technical possibility of mitigating flow assurance threats (slugging in early or
late life, reservoir souring from water injection).
Erosion velocity limits in risers or flowlines for gas lift.
Network flow analysis using flow model for steady state flow rates and or transient
multiphase flow simulators for transient startup and shutdown sequencing.
Support of operating procedures development.