processes can be categorized as batch, continuous, and discrete manufacturing
[21]. A batch process represents a discontinuous production process that consists
of various unit operations. In contrast, a continuous process runs through production
without interruption, and raw materials and intermediates are processed by passing
each production stage. Discrete parts manufacturing illustrates the production processes that create a specific quantity of intermediates. Once the specific quantity is
achieved, further processing occurs. Accurate classification of the process is essential for selecting the appropriate standards and identifying the key process steps (unit
operations).
Following the identification of all the relevant process components and their
classification into “with product contact,” “utilities-relevant,” and other markings,
their semantics must be defined. This terminology highlights the need for correct
Fig. 7 The different steps of process analysis with exemplary components
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