An application of expert system technology to development of chemical-engineering both processes and schemes models are considered. The using of knowledge based tools are discussed on example of gases purifying processes. The intellectual simulation system - SSP EXPERT for sewages and effluent gases purification have been developed. It is built on the basis of standard shell and includes "in-built" expert system. Intellectual system for chemical engineering processes simulation combines traditional modeling methods, based on using of physico-chemical laws and experimental data processing with artificial intelligence technique. Application of the artificial intelligence techniques to mathematical models elaboration allows both to save time and to improve their quality.