ISA S88 standards for continuous plants!
Generally, speak to stalwarts in refinery and petrochemicals and they may not be interested talking batch. S88 is taboo.
The standard has been so well designed by the ISA and supported by leading control systems, that it can be very effectively used in not only defining control strategies for continuos processes, but also greatly enhancing operator interface.
Does it make sense? Your thoughts please...
Alok Khatlawala
There have been many papers
There have been many papers presented at WBF meeting that cover this topic.
And yes, in general many of the principles that apply to batch can also apply to continuous – in fact most plants have a bit of both anyway. S88 proposes a modular and hierarchical structure that fits all kinds of plant.
The S88 Physical model lends itself to continuous processes well, although there is some debate about the boundaries of Unit, Equipment models etc
The question with Continuous is where is the batch? And yes there is one, even in continuous plants, typically it is a slice of time but it may also be delineated by grade changes etc.
S88 says nothing about operator interfaces so I can't quite relate to that comment although you can and should identify what the operator interface is for each of the ‘S88 modules’.
And as for Control Strategies, they are typically multiple levels of Control Models, and S88 only really says that they can exist and are state setting and monitoring entities
Francis
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