Digital Twins for Process Industries

Abstract

The term process industry is used to refer to a broad range of applications involving the storage and transportation of processing of liquids or gasses. Common components found across such industries include vessels for storage and processing, pipes connecting the vessels and valves and pumps for moving materials between vessels. It is notable that the material that is being processed, e.g. oil, is of a continuous nature, so it is not possible to identify discrete items that are distinct from other items. This is the major difference between the process industry and the manufacturing industry. In manufacturing, a resource such as a robot may perform an operation such as pick-and-place on a workpiece. However, such operations do not occur in an industrial process, as there are no workpieces. Instead, the process acts on the substances being processed through control loops. Key elements of a loop are a measurement, controller, setpoint and actuator. Before discussing digital twins of industrial processes, it is necessary to discuss fundamental concepts such as process equipment, models of the physical process, instrumentation and control systems. Process industry domain terms that are important for the eventual discussion on digital twins are italicized when first used.