Real-Time Optimization of a Gasoline Run-Down Header Blending Operation

Refiners around the world are continually seeking ways to maximize margin on gasoline production.  Optimization of various unit operations and gasoline blending using online blending packages are commonly employed.  However, an area of opportunity that is less commonly exploited is the optimization of gasoline run-down headers.  The economic benefits of gasoline run-down header optimization are enormous, but there are many challenges.

Run-down header blending operation optimization is challenging since many process units feed into the run-down header.  Multiple control rooms, process operators and control systems are involved.  This poses a significant challenge for a single application to optimize the entire system in real-time.  Secondly, many of the process streams entering the run-down headers have multiple dispositions.  Thirdly, the gasoline blending operation is highly non-linear.  Lastly an on-line stream property measurement system that is sufficiently fast for on-line control and is able to provide a reliable property measurement over the entire blending range of components is a challenge.

Suncor Energy at Edmonton Refinery has been active in real-time optimization of the refinery operation for the last several years.  While a majority of process units are being optimized using Advanced Process Control (APC), gasoline blending operation was, till recently, optimized using offline LP tools.

The gasoline blending operation at Suncor comprises Final Gasoline Blending operation and Gasoline Run-down Headers operation.  An innovative project to optimize the gasoline blending operation in the run-down header in real-time was recently completed and is the subject of this paper.