Process Design

Overcoming barriers to the application of process synthesis techniques in industry

Abstract:

There has been a great deal of interest in a range of systematic approaches to process design, but despite their promise, these techniques continue to be underutilized in industry. On the other hand process simulation is used extensively. The typical approach remains to start with a previous design, perform process studies based on the experience of the design team and then move forward to the design phase. The focus is usually more equipment based than process based and more single plant unit based than total site based. The result is processes that are typically significantly less efficient than one might have expected. Once capital has been expended (grass roots or retrofit), the opportunity for economically viable improvement through application of these systematic methodologies is significantly diminished.

The reasons for this reality from the perspective of a process consultant are explored. Aspects addressed include:
-design practices
-over-hyping pinch technology and other practices as easy to use and yielding dramatic improvements
-formulation of process design problems (over-constrained, the current practice is the only solution)
-perceptions of risk
-plant evolution
-upper management signals to the design team over the lifecycle of projects
-organizational boundaries
-organizational power of plant engineers to determine design of new units (rather than process design engineers)
-equipment focus

Recognition of the underlying problems and a commitment by project sponsors to a plan addressing the key issues is critical to significant improvement. With this in place a plan simultaneously addressing the following aspects is recommended:
-Management action to reinforce the desired outcome
-A systematic approach to process risk
-The integrated application of process synthesis techniques built into the design process rather than as optional additions to the traditional process
-Establish a priority of first total-site dynamics, then the process and then equipment (rather than the reverse)