Application of the graph theory and matrix calculus for optimal HAZOP nodes order determination

Abstract This paper presents a method for determining the optimal order of HAZOP nodes, as well as the issues related with a description of streams flows of information among the elements of process systems. Determination of the optimal HAZOP nodes sequence (a sequence of nodes being sources of information streams are analyzed before the nodes receiving the streams) allows avoiding the necessity of assuming and afterward verifying an existence of possible deviation and their transmission from the upstream nodes to the one being the subject of the analysis. This procedure constitutes a difficult task for process installations with a complicated structure. The optimal order of HAZOP nodes can be determined by using the graph theory and the matrix calculus. The described method has been implemented to carry out analyzes of complicated process systems. The main rules of the proposed method and results of application are HAZOP analyzes of steam boiler plant and one of the Underground Gas Storage Plant operated in Poland are presented in the paper.