Scaling to Pilot and Production

Scaling from bench to pilot is possibly the most difficult challenge facing process R&D groups.

Other parts of product development are often straightforward by comparison. 

For example, both market research and bench research basically involve information acquisition.  Both of these activities can be automated to a high degree. 

There are three major obstacles to the automation of scaling experiments:

•         Matrix Peculiarities
•         Non-linear Scaling
•         Manufacturing Constraints

Because of these major obstacles, every pilot operation presents never-before-seen challenges, and requires the highest level of ingenuity from the technical staff.  

The emphasis in this part of the development effort is the firm establishment of economic feasibility.  Prior to establishing economic feasibility, the chemist must determine corporate interest and technical feasibility.

Economic feasibility is not an issue in purifications performed strictly at the technical feasibility (small scale) level.  However, for process scaling to pilot and production, good economics are mandatory.

An important first step in assessing economic feasibility is the consideration of issues around scaling.  All process steps, equipment, and supplies must be evaluated for their suitability at pilot and production scales.  Bench scale technical feasibility studies that involved filtration through 0.2 mm PTFE syringe filters, for instance, are not easily scalable.  Suitable substitutes must be found.  In some cases, this early part of development work may reveal that some steps require substantial changes to ensure success at larger scales.  In other cases, the difficulty inherent in substitution may merit the consideration of purchasing new equipment for piloting and production.  Capital equipment outlays must always be justified in terms of their applicability to existing or future processes and products. 

Although process or production engineers must make the final determination of economic feasibility, process chemists must assist in the determination.  Misunderstanding of even a few operations can lead to inaccurate cost projections.  The chemist must be included in the determination of economic feasibility to ensure that operations are faithfully extrapolated from the bench model.  The chemist must also be present during pilot operations to ensure that essential operations are executed properly.  It is equally important for the chemist to be present in production startup, and to monitor production on a regular basis.