At Smith Rea we have used process modelling tools
(e.g. Aspentech’s HYSYS) extensively to characterise the behaviour
of hydrocarbons in process. The use of such models allows the calculation
of shrinkages, estimation of unmeasured streams and use of cloned components
allows direct allocation using the simulation model itself. Simulations are
also used in studies to model actual plant performance which enables forecasting
of allocated quantities based on Field profile data.
In addition Smith Rea has developed modelling
techniques using recognised chemical engineering calculations (e.g. flash
calculations using component k-factors) to replicate the results of commercial
simulation models. These techniques have the advantage of allowing the incorporation
of models directly into allocation code without the need to run separate
simulation software.