Process intensification processes /techniques

The term process intensification is used synonymously with minimization. Process intensification is also often used more specifically to describe new technologies which reduce the size of unit operations equipment, particularly reactors. Innovative process intensification techniques are receiving more and more attention. Interesting possibilities for a range of unit operations, including reaction, gas-liq-... 

Therefore, in this definition process intensification encompasses both novel apparatus and techniques which are designed to bring dramatic improvements in production and processing (Figure 1.8) [25]. As a result, safe, cheaper, compact, sustainable (environmentally friendly), and energy-efficient technologies are obtained. 

Reactive distillation is one of the classic techniques of process intensification. This combination of reaction and distillation was first developed by Eastman Kodak under the 1984 patent in which methyl acetate was produced from methanol and acetic acid. One of the key elements of the design is to use the acetic acid as both a reactant and an extraction solvent within the system, thereby breaking the azeotrope that exists within the system. Likewise, the addition of the catalyst to the system allowed sufficient residence time such that high yields could be obtained, making the process commercially viable. Other examples in which reactive distillation may enhance selectivity include those of serial reactions, in which the intermediate is the desired product, and the reaction and separation rates can be systematically controlled to optimize the yield of the desired intermediate. ... 

In summary, the Avada process is an excellent example of process intensification to achieve higher energy efficiency and reduction of waste streams due to the use of a solid acid catalyst. The successful application of supported HP As for the production of ethyl acetate paves the way for future applications of supported HP As in new green processes for the production of other chemicals, fuels and lubricants. Our results also show that application of characterization techniques enables a better understanding of the effects of process parameters on reactivity and the eventual rational design of more active catalysts. 

Heat transfer has been identified by Rlay 13 as an important area in which process intensification is expected to offer major benefits in terms of energy efficiency, pollution control and plant operating costs. So-called passive techniques including modifying the walls of a plant unit, for example, are routinely used to improve heat transfer coefficients in... 

Microreactors evolved from the process intensification concepts and microfabrication techniques developed for the microelectronics industry. Process intensification was pioneered in the 1970s, arguably by Imperial Chemical Industries (ICI) researcher Colin Ramshaw, who began developing technologies and approaches that considerably reduced the physical size of unit operations while maintaining their... 

The use of electromagnetic techniques represents the final method for process intensification of heat transfer that will be dealt with here. Developments in the fuel cell sector hold out the promise of cheap electric power based on surplus hydrogen in chemical plants. The liberalization of the energy sector has also cut electricity prices and enhanced the attractiveness of using electricity in connection with chemical reactors. The precise regulation possible with electrical processes and their clean, environmentally friendly nature are further inducements for their application. 

Examples of strategies for safe designs are prevent large volumes, intensify contact, reduce the need for aids (like solvents), use little intermediate storage. One can immediately see the similarities between intrinsically safe design and process intensification. This also means that applying process intensification techniques is beneficial for process safety. 

Process intensification consists of the development of novel apparatuses and techniques that, compared to those commonly used today, are expected to bring dramatic improvements in manufacturing and processing, substantially decreasing the ratio of equipment size to production capacity, energy consumption, or waste production and ultimately resulting in cheaper and more sustainable technologies (35). 

Membranes and membrane processes are best suited in this context as their basic aspects well satisfy the requirements of process intensification for a sustainable industrial production. In fact, they are precise and flexible processing techniques, able to maximize phase contact, integrate conversion and separation processes, with improved efficiency and with significantly lower energy requirements compared to conventional techniques. 

Note that the evolution of design between the levels 4 and 5 can generate a number of alternatives, but these should not affect the basic flowsheet structure defined at the reactor/separations/recycle level. In addition, employing complex units and process-intensification techniques can produce more compact flowsheet and cheaper hardware. 

The productivity can be greatly improved by the implementation of continuous operations and the use of process-intensification techniques, such as reactive distillation. The replacement of a homogeneous catalyst by a heterogeneous one is highly desirable. These aspects will be discussed in greater detail in the next section. 

The methodology of conceptual process synthesis for process intensification is focused on the generation of the novel concepts and techniques for the processing tasks. The methodology of conceptual process synthesis for process intensification is illustrated in Figure 1. 

Part 11 elaborates on some of the topics presented and discussed in recent CPAC Summer Institute sessions at the University of Washington. The impact of microinstrumentation on high throughput experimentation and process intensification will be highlighted in these chapters as a valuable and emerging field of technology. The initial chapters describe fimdamentals and hardware developments and some techniques to monitor and characterize them. These are followed by a series of chapters that emphasize the applications and impact of the microdevices. 

Process Intensification designates the development of techniques and new equipment that can achieve significant improvement in productivity, as well as in the energetic efficiency and environmental friendliness of processes. The development in this field can be classified in two areas (Stankiewicz and Moulijn, 2000) ... 

The classical methods of chemical and fermentative synthesis and purification are augmented by the powerful genetically modified cellular systems of production, by transgenic animals and plants, as well as by sophisticated techniques of syntliesis, analysis, purification, such as chual catalysts, micro-reactors, and process intensification. 

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