Glossary · Batch and process operations
Process cell
German: Prozesszelle
In ISA-88 batch control, a process cell is a logical grouping of equipment that includes the equipment required for the production of one or more batches. It defines the span of logical control of one set of process equipment within an area.
- Batch control
- Process industry
- Standards
In one sentence
In ISA-88, a process cell groups the equipment needed to produce one or more batches and sets the span of control within an area.
Example
Process cell PC1 contains two reactors, a filter and a dryer; a batch moves through a train of these units.
How it applies
- Engineering: The process cell is usually the scope of one batch management instance; recipes at the procedure level run within a process cell.
- Operation: Batches use a train, the set of units within the process cell used for a particular batch. The batch system allocates units to avoid conflicts.
- Security: Process cells are often natural candidates for network segmentation, although zones in IEC 62443 are defined by risk, not by the batch model.
- Documentation: Plant documentation often has one part per process cell, with an overview of units, product flows and shared equipment, before going into unit details.
Process cell vs. unit
A process cell produces complete batches with several units. A Unit (ISA-88) carries out major processing activities on a batch and typically holds only one batch at a time.