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Research paper−55−Synthesiology - English edition Vol.2 No.1 pp.55-63 (Jun. 2009) reaction and separation, using a single unit of equipment; and “enhanced safety,” represented by efforts to minimize waste. Described as such, it is evident that PI has much in common with the concept of Minimal Manufacturing (MM)[6] , which is promoted by National Institute of Advanced Industrial Science and Technology (AIST). The MM concept is to manufacture only as many components and products as required, when required, using only the raw materials and equipment that are truly necessary. Perhaps MM is superior to PI, since PI only deals with chemical processes. However, PI has the same goal as MM. MM attempts to reconcile seemingly conflicting demands, such as energy saving with resource conservation, high efficiency with low cost, and high functionality with new features. We have developed a heat-integrated distillation column (HIDiC) process where the heat transfer and the distillation operations are integrated, with the goal of energy saving during the distillation process. The process from the basic research to the practical application has not been smooth. Looking back, we can state that it was a R&D called Full Research. Also it was not intended from the beginning, but the research can be termed a successful example of PI. What follows is a description of the history, method of conceptualization, and approach to practical application of the HIDiC process in relation to PI. More specifically, we attempt to show that the designing and developing a new process through “detuning” from the thermodynamically ideal state is one method of achieving PI.2 Approach to energy saving – thermodynamically ideal state and “detuning”To discuss the innovation and energy saving in distillation 1 Introduction“Process intensification (PI)” is discussed as a new paradigm in the field of chemical engineering where chemical processes and/or their components such as reaction apparatuses and separation devices are investigated. However, the definition of PI at present is not particularly clear. As Hirata mentioned[1], there is only a vague understanding of PI that is shared among the researchers. “Successful implementation of PI results in dramatic improvement in performance.” The goal is to achieve a performance improvement of at least tenfold. It is called a “quantum leap.” Performance improvements that can be achieved through advancement of existing technology by modifying processes and equipment can be limited to a few dozen percent at most. The realization of a “quantum leap” is necessary for a fundamental change, starting from the operating principle and the sizes and shapes of the equipment.Looking back at the history of PI, it can be understood that the term itself is not new. According to Kuroda and Matsumoto [2], the term PI was used over 30 years ago in the United Kingdom within the context of safe design and size reduction of chemical plants and processes. However, the outset of increasing interest toward PI in the United States of America and Japan was marked by an article by Stankiewicz and Moulijn [3]. The authors’ perspectives on PI have since been changing slowly [4] [5], but a few keywords have remained constant. They are “miniaturization” and “simplification,” represented by efforts to reduce the equipment size and the number of operations in a given process; “increased efficiency,” represented by efforts to boost performance and energy saving; “integration” and “combination,” represented by efforts for simultaneous processing of multiple operations such as distillation and heat transfer, or - Process intensification for energy savings through concept of “detuning” from ideal state -Masaru Nakaiwa* and Takao OhmoriResearch Institute for Innovation in Sustainable Chemistry, AIST Tsukuba Central 5, Higashi 1-1-1, Tsukuba 305-8565, Japan *E-mail : nakaiwa-m@aist.go.jp Received original manuscript October 24,2008, Revisions received January 13,2009, Accepted January 13,2009A methodology of process intensification was discussed through the concept of “detuning” from the ideal state, especially for the energy-saving continuous distillation processes, which are typical energy consumer in the chemical and petrochemical industries. First, the reversible distillation was shown as the thermodynamically ideal state. Then, it was indicated that several energy efficient modifications of distillation processes can be obtained by “detuning” or simplifying the reversible system. Among these modifications, an internally heat-integrated distillation column (HIDiC) was one of the most promising options. The development of the HIDiC in the national projects was reviewed and the reduction of energy consumption by the HIDiC was estimated to be 60 % of the conventional column from the results of the projects.Innovation in distillation processesKeywords : Process intensification, distillation process, energy saving, detuning[Translation from Synthesiology, Vol.2, No.1, p.51-59 (2009)]

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