Expert Systems in the Selection of Process Equipment

Abstract

Process equipment is specified at the design stage by well established technical considerations and such calculations have been the subject of intensive committment to solution by computer. However, selection of items of equipment is largely dependent on the skill and experience of specialist procurement engineers and access to large unco-ordinated databases such as manufacturers’ technical literature.

The latter area is amenable to the application of expert systems where judgement and experience are important criteria. This must be combined with conventional numerical treatment of the design and specification stage. Many existing expert system ‘shells’ do not incorporate a sufficiently powerful calculation capability.

In this paper, we examine the development of consultation programmes for the selection of process valves, as a prototype of equipment selection, under three different programming environments, i.e. Pascal, Lisp and Prolog. We examine the advantages and disadvantages of these three different environments. We also discuss efficient ways of making decisions for process valve selection. Pascal, Lisp and Prolog are all suitable for this task and we suggest appropriate decision making techniques within each environment.