Refinery planning : a mature technology, yes but…
Reinventing refinery planning
Refinery planning has been among the first applications of mathematical programming in the industry. Linear programming has been successfully applied to both long term and short term refinery planning.
Fundamentally, linear programming is about calculating a set of activities under the condition that no activity should be used if a more profitable activity or combination of activities was available. In addition, the method implies values to be placed on scarce resources (marginal costs) which define the opportunities open to the company.
The practice of linear programming by oil refiners has evolved over time in two, somewhat competing directions
- Running a large number of cases in order to quickly evaluate various crude oils available in the market from a trader’s perspective
- A short term perspective on refinery planning viewed as a preparation step to refinery scheduling: this view on refinery planning requires a more accurate representation of both the logistics and stream movements (hence a generalized use of pooling) and of the process units performance (hence the use of non-linear process models)
Another important factor which has impacted the way linear programming models were used in recent years has been the arrival of a younger generation of users subject to a higher turnover. In the past, a certain level of expertise in linear programming model building and in-depth interpretation of results was achieved after several years of practice. By contrast, today’s users are more interested in a quick overview of a large number of solutions.
The new generation refinery planning systems must therefore address the following requirements
Princeps’ refinery planning solution: PrincepsLP
Princeps’ refinery planning system offers a complete palette of features such as multi-period and multi-refinery planning, pooling and successive linear programming, non-linear process modeling using a simulator interface.
In addition to these traditional capabilities, the most distinctive characteristics of Princeps’ refinery planning system are:
Ultimately, both Princeps’ refinery planning and refinery scheduling solutions will be incorporated within the same framework (the current flowers framework) in order to:
Extremely simplified model building rules
which make the system very easy to learn by a new user (less than 1 day is needed)
A very flexible tables organization
which makes almost any data structure acceptable as long as a data item can be retrieved without ambiguity
Powerful scenario generation
which considerably simplifies alternative scenarios definition, execution and reporting
Share permanent data
and process models
Simplify and unify model building
… and maintenance which will be performed through the block diagrams formalism
Enable LP users to benefit from the features already available with flowers:
- Full versioning and archiving of models and cases
- Graphical model building
- Easy graphical reporting
- Simple and easy comparison between refinery plan and refinery schedule