8. Process Selection

The process selection approach based on the principles embedded in the Theory of Constraints Methodology is used to perform a structured evaluation in two stages with the goal of arriving at the best process option for implementation. The Stage 1, focussed in this section, represents an initial evaluation of all process options to arrive at a short list of the preferred options for detailed evaluation in Stage 2. It consists of a four-step analysis, namely, identification of options, identification of key performance aspects and associated performance measures, assessment of impact of the options on the performance aspects, and an overall assessment. For illustration, a demonstration of the Stage 1 evaluation considers five process options for the recovery of vanadium from flyash. On the basis of equal weighting factors for different performance aspects, and scoring and ranking, two preferred process options were short-listed. The simple but innovative approach can be considered an effective tool for the process selection team and would benefit the decision makers to arrive at a logical outcome in a consistent manner.