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Chemical process miniaturization refers to a philosophical concept within the discipline of process design that challenges the notion of "economy of scale" or "bigger is better". In this context, process design refers to the discipline taught primarily to chemical engineers. However, the emerging discipline of process miniaturization will involve integrated knowledge from many areas; as examples, systems engineering and design, remote measurement and control using intelligent sensors, biological process systems engineering, and advanced manufacturing robotics, etc. One of the challenges of chemical engineering has been to design processes based on chemical laboratory-scale methods, and to scale-up processes so that products can be manufactured that are economically affordable. As a process becomes larger, more product can be produced per unit time, so when a process technology becomes established or mature, and operates consistently without upsets or “downtime”, more economic efficiency can be gained from scale-up. Given a fixed price for the feedstock (e.g. the price per barrel of crude oil), the product cost can be decreased using a larger scale process because the capital investment and operational costs do not normally increase linearly with scale. For example, the capacity or volume of a cylindrical vessel used to produce a product increases proportional to the square of the radius of the cylinder, so cost of materials per unit volume decreases. But the costs to design and fabricate the vessel have traditionally been less sensitive to scale. In other words, one can design a small vessel and fabricate it for about the same cost as the larger vessel. In addition, the cost to control and operate a process (or a process unit component) does not change substantially with the scale. For example, if it takes one operator to operate a small process, that same operator can probably operate the larger process. The economy of scale concept, as taught to chemical engineers, has led to the notion that one of the objectives of process development and design is to achieve “economy of scale” by scaling-up to the largest possible size processing plant so that the product cost can be economically affordable. This disciplinary philosophy has been reinforced by example designs in the petroleum refining and petrochemical industries, where feedstocks have been transported as fluids in pipelines, large tanker ships, and railcars. Fluids, by definition are materials that flow and can be transferred using pumps or gravity. Therefore, large pumps, valves, and pipelines exist to transfer large amounts of fluids in the process industries. Process miniaturization, in contrast, will involve processing of large amounts of solids from renewable biomass resources; therefore, new thinking towards process designs optimized for solids processing will be required. The concept of a microprocess has been defined by S. S. Sofer while a professor at the New Jersey Institute of Technology. A microprocess has the following characteristics:〔"Microprocesses - Sometimes Smaller is Better", S. S. Sofer, Chemical Processing, May 1987 (ref )〕 :1) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Process miniaturization」の詳細全文を読む スポンサード リンク
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