### Decoding Complexity with Sankey Diagrams: A Guide to Visualizing Flow and Material Balances in Industrial Processes
Sankey diagrams are a highly effective tool for representing and understanding the flow and transformation of materials, energy, and other resources within industrial processes. Originating from Scottish engineer Captain Matthew Boulton, who first used them in the early 1800s to illustrate steam flow in a factory, Sankey diagrams have developed significantly over time to become an indispensable visual representation technique in fields ranging from energy systems and environmental studies to business processes and engineering design. This article serves as a comprehensive guide to decoding complexity within industrial processes through the application of Sankey diagrams.
#### Key Features of Sankey Diagrams
**Flow Representation:** Sankey diagrams are characterized by their ability to visually depict the magnitude of flows based on the width of the arrows, making it easier to understand which processes are the most significant contributors to the output.
**Material Balances:** By illustrating the sources, transfers, and destinations of materials, Sankey diagrams enable a clear visualization of material balances, helping in identifying where materials are being lost or gained within the process.
**Decision Making:** The clear depiction of materials moving through different stages of a process supports decision-making by highlighting inefficiencies, bottlenecks, or areas requiring improvement.
#### Creation of Sankey Diagrams
**Information Gathering:** The first step in creating a Sankey diagram involves gathering detailed information about all material or energy flows within the selected process. This information should include the sources, volumes, and destinations of these materials across the process steps.
**Tool Selection:** A variety of software tools are available for creating Sankey diagrams, including specialized software such as Adobe Illustrator, specialized diagramming software like LucidChart or Draw.io, and more technical tools like MATLAB or Python libraries (such as PySankey).
**Layout Design:** This involves arranging the nodes (representing sources, processes, and sinks) and the flow links based on their relative importance or the nature of the connections. The width of the flow lines should scale with the volume or energy of the flow.
**Design and Aesthetics:** Care must be taken to ensure the diagram is visually appealing, with a consistent color scheme, font, and scale. This aids in making the diagram easily understandable for stakeholders with varying levels of technical expertise.
#### Application in Industrial Processes
**Process Mapping:** Using Sankey diagrams for mapping out the flow of materials or energy in different industrial processes is crucial for identifying potential improvements and optimization opportunities.
**Energy Audit:** These diagrams are particularly useful in conducting energy audits, helping in quantifying energy consumption and identifying areas for energy efficiency improvements.
**Environmental Studies:** Sankey diagrams can illustrate the flow of environmental pollutants within and outside a process, aiding in the design of effective waste management systems.
**Business Process Modeling:** Similarly, they can be used to depict the flow of materials or products through business processes, assisting in resource management and supply chain optimization.
### Conclusion
Sankey diagrams are invaluable in any context where understanding, optimizing, or improving flow within a system is required. By leveraging their effectiveness in visualizing materials, energy, or resources flow, they become an indispensable tool for decision-makers in industrial sectors. Whether used for process analysis, environmental impact assessment, or business process optimization, Sankey diagrams offer a clear and comprehensive perspective, enabling better-informed decisions and improvements in efficiency and sustainability across industrial and systemic processes.
