A process comparison should include all relevant respectively all known alternatives. This requires the creation of a good database.

Often detailed technical and financial information is available on a well-known process, for instance the process used by the customer. Obtaining comparable data on alternative processes can be a good deal more time-consuming. A variety of information sources are available. These range from patent searches to analyzing scientific publications, official publications, environmental and trading statistics and monitoring reports in the media.

Further data can be derived by carrying out process calculations on the basis of the information obtained. Experienced development engineers draw up flow charts for the processes in question, perform mass and energy balance calculations and thus derive data on the underlying energy and raw material requirements. The necessary capital expenditures can be calculated from this with varying degrees of accuracy depending on requirements.

From this our staff, who have experience with managing production plants, can calculate production costs, even for production processes with which they are not really familiar.

We know from experience that the accuracy of the data obtained on different processes can vary. To make this clear when drawing conclusions, the economic calculations can be carried out with “vague figures” or probability distributions of important input figures. The sensitivity analysis shows the parameters that are relevant for a decision.

Although all calculations are supported by up-to-date software these days, working with an experienced and interdisciplinary team of experts is the only way to ensure topquality process evaluation.