Digital Chemical Engineering (Mar 2023)
Digitalisation of chemical processes as graphs and applications of modular decomposition to process design and analysis
Abstract
The digital transformation of chemical processes requires methods that support the modelling and analysis tools suitable to decompose complex systems into manageable components at all stages of process development, starting with conceptual design and analysis. This paper presents examples on how the digitalisation of chemical processes as graphs can facilitate their study and analysis for developing alternative process designs. In a process graph, inputs, outputs and unit operations are represented as nodes and streams are edges which can be weighted using process variables such as flow rate. Once a process is represented as a graph, community detection algorithms can be applied to identify process modules and obtain their modularity. The novel approach presented is based on modular decompositions to identify highly related unit operations in a flowsheet which can be analysed for insightful directions to improve a chemical process. The approach showed to be helpful in analysing a biofuel production process by adopting a combined economic and greenhouse gas emissions analysis at a modular level for hot spot analysis and identification of opportunities for decarbonisation. In an application to process integration, CO2 capture and utilisation networks are analysed in terms of its modularity and efficiency in processing CO2. In both cases, the improved designs had higher modularity values suggesting a correlation between modularity and technical performance which needs to be investigated further. Finally, prospective applications of modularity and modular decomposition approaches to realise several digitalisation tasks are presented.
