Process Systems Engineering

Process engineering focuses on the design, operation, control, optimization and Intensification of chemical, physical, and biological processes. Process engineering encompasses a vast range of industries, such as chemical, petrochemical, agriculture, mineral processing, advanced material, food, pharmaceutical, software development and biotechnological industries. The application of systematic computer-based methods to process engineering is process systems engineering.

Process engineering involves translating the needs of the customer into (typically) production facilities that convert "raw materials" into value-added components. These components are transported to the next stage of the supply chain, typically packaging engineering. Some larger-volume processes such as petroleum refining processes tend to transfer the products into transportation (trucks or rail) that are then directed to distributors or bulk outlets.

Prior to construction, the design work of process engineering begins with a block diagram showing raw materials and the transformations (unit operations) desired. The design work then progresses to a process flow diagram (PFD) where material flow paths, storage equipment (such as tanks and silos), transformations (such as distillation columns, receiver/head tanks, mixing, separations, pumping, etc.) and flowrates are specified, as well as a list of all pipes and conveyors and their contents, material properties such as density, viscosity, particle-size distribution, flowrates, pressures, temperatures, and materials of construction for the piping and unit operations.

The process flow diagram is then used to develop a piping and instrumentation diagram (P&ID) which includes pipe and conveyor sizing information to address the desired flowrates, process controls (such as tank level indications, material flow meters, weighing devices, motor speed controls, temperature and pressure indicators/controllers, etc.). The P&ID is then used as a basis of design for developing the "system operation guide" or "functional design specification" which outlines the operation of the process.

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