Rule Based Expert System Which Configures Gas Chromatographs

Abstract

This paper discusses the application of expert system technology to the configuration of process gas chromatographs (GCs). A GC is a tool for performing quantitative analysis of liquid and gaseous mixtures by separating their constituents into individual compounds. The analysis is necessary to ensure that the chemical plant is operating correctly and that the customer's product is meeting required levels of purity and consistency. The instrument can measure chemical concentrations down to parts per billion. The customer specifies the application in the form of a "process stream". The process stream describes the type of chemicals that are present and the concentration range be analyzed. GC applications are typically, but not limited to, analysis of environmental samples and hydrocarbons. Different combinations of hydrocarbons require different combinations of hardware in order to be properly analyzed. There are an enormous number of variables that need to be considered when configuring a GC system. This makes the configuration problem a difficult one.