Abstract
The paper proposes a systematic approach to the elaboration of a structured mathematical model and modeling of chemical and technological systems under uncertainty exemplified by a sulfur production unit. The novelty of the suggested method lies in the choice of a suitable model type for each element of the system based on the systematic analysis, development of the selected model type and their merger into a unified system of models. The method was successfully implemented to construct a system of models for major units of the catalytic reforming plant at the Atyrau Oil Refinery (Republic of Kazakhstan). The study compares existing results, modeling results based on the suggested method and experimental results obtained using an LG-setup of the Atyrau Oil Refinery. The deliverables demonstrate high efficacy and excellence of the approach to the modeling of interconnected equipment (chemical and technological systems).