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Mass integration provides a comprehensive methodology for targeting yields, emissions, and capacities, and designing reaction, separation, and waste-processing systems. It now is starting to play an important role industrially.
The design of any industrial process must address two important dimensions: mass and energy. Mass involves the creation and routing of chemical species in reaction, separation, and byproduct/waste-processing systems. These constitute the core of the process and define a company's technology base. Energy provides the necessary heating, cooling, and shaftwork for those systems.
Design always has been part science and part art. Engineers typically start with a previous design and use experiencebased rules and know-how, along with their creativity, to evolve a better design. They rely on computer-based tools such as process simulators and unit-operation design programs.
The result of this approach has been good designs that work - but that often have substantial scope for improvement. Process integration
Starting in the 1970s, engineers began to realize that correctly assembling the process building blocks is just as important as properly selecting and designing individual components. They also discovered that fundamental principles can guide this assembly.
This led to the concept of integrated process design or process integration, which emphasizes the unity of the entire process. It addresses the big picture first using fundamental principles, and then tackles design details only after the major structural decisions have been made. This approach assures that the correct details receive attention.
The first significant success of this approach was in energy integration. Socalled thermal pinch technology or pinch analysis became available to industry about 1980 and, since then, has matured and been widely applied.
Pinch analysis is the definitive way to design heat recovery networks, select process-wide utility heating and cooling levels, and establish the energy/capital tradeoff for heat recovery equipment. It also provides insight into other elements of design - but it does not address issues related to mass in the reaction, separation, and byproduct/wasteprocessing systems.
Since the introduction of pinch analysis in the 1980s, substantial progress has been made in the broader discipline of energy integration (1). Steam, fuel, and on-site power-generation systems now can be analyzed as integrated systems, and the interactions among them can be understood for improved design and operation.
The most recent success...