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Most high-margin growth opportunities lie in high-grade specialty chemicals. To realize these opportunities, manufacturers are looking to distributed modular production facilities. Process intensification could help to enable these new technologies.
Two fundamental tenets have driven chemical engineering over the last century. The first is economy of scale - which reasons that constructing larger chemical plants improves capital efficiency and resource utilization. thereby reducing operating costs and product price, as well as increasing profit.
The second is unit operations - which are a consistent set of building blocks that can be used to design a plant. The unit operations framework was defined to provide method and structure to the synthesis and analysis of chemical plants, as well as a rational and systematic path for performing process design calculations. This framework was particularly critical when the slide rule, not the computer, was the dominant tool for performing calculations. While slide rules have become obsolete, unit operations remained the central paradigm in the design, simulation, and optimization of chemical processes.
These principles - economy of scale and unit operations - have not persisted without challenge. The concept of process intensification (PI), for example, has been around since the mid-20th century (1), but has received increased attention in the past two decades. The objective of PI is to design substantially smaller plants, while improving operational safety, environmental performance, and energy efficiency. The Rapid Advancement in Process Intensification Deployment (RAPID) Manufacturing Institute, supported by the U.S. Dept, of Energy (DOE), has recently placed the spotlight on PI in the U.S. RAPID's aim is to target and promote major advances in energy efficiency and productivity in the process industries. It supports research on related topics ranging from PI fundamentals, modeling and simulation, and module manufacturing, to applications in chemical and commodity processing, natural gas upgrading, and renewable bioproducts.
PI challenges the conventional approach of "one unit, one operation" by combining multiple unit operations in the same physical device. Intensified systems minimize transfer and transport limitations by bringing multiple physical and chemical processes in close physical proximity. Phenomena such as catalytic reactions, for example, are governed by their intrinsic rates, rather than by diffusion through the catalyst structure. Intensified devices tend to be smaller and more efficient than their conventional counterparts....