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Coiled Tubular Reactors Significantly Improve Energy Efficiency Author/Source: China Chemical Industry News Date: 3-07-2019 Clicks: 1 The second phase of the research project on efficient coiled tubular reactors, carried out jointly by Wuhan Donghai Petrochemical Heavy Equipment Co., Ltd. and the Institute of Process Engineering of the Chinese Academy of Sciences, has recently been completed. This study developed a design method for coiled tubular reactors tailored to different operating principles, which increases the heat transfer capacity of such reactors by over 50% compared to tubular fixed-bed reactors, thereby significantly enhancing the production efficiency of enterprises. “Compared with conventional fixed-bed reactors, the heat transfer medium in a coiled-tube reactor is located inside the reactor tubes; and within the same volume of housing, it provides a larger heat exchange area. This allows for the rapid removal of excess reaction heat, thereby promoting the forward progress of the reaction and increasing its conversion rate. It also helps to prevent catalyst deactivation and extend the catalyst’s service life. ”Li Mingkai, technical director of Donghai Petrochemical Refitting Company, said. According to him, the coiled tubular reactor can meet both radial and axial flow requirements in terms of structure, making it suitable for applications with high demands on reactor pressure drop. Its catalyst can be installed and removed easily, and its heat transfer capacity is more than 50% higher than that of a tubular fixed-bed reactor. By adjusting the temperature of the medium surrounding the tube, a gradient distribution can be achieved, enabling precise control over the reaction temperature. Li Mingkai emphasized particularly: \"Based on this design method, we optimized the arrangement of the tubes in the coiled heat exchanger. Through simulation calculations, arrangements such as different layouts within the same layer and staggered layouts across different layers were adopted, thereby enabling a more rational distribution of the various media inside the heat exchanger and more efficient use of heat. This results in a heat transfer efficiency that is about 15% higher than that of conventional multi-stream coiled tube heat exchangers.\" ” It is understood that the coiled tubular reactor designed using this achievement has been applied in various pilot-scale units, including reactors for the synthesis of ethylene glycol and olefin-based products. Changing the reactor design allows for more stringent control of pressure drops and higher heat transfer efficiency, effectively addressing the issues of equipment size limitations and manufacturing challenges that arise during the scaling up of the installation. At the same time, the coiled-tube heat exchangers designed using this method have been widely applied in low-temperature methanol washing units, natural gas extraction, purification, storage, and transportation systems, as well as in fine chemical and pharmaceutical production facilities. They have achieved significant energy-saving and consumption-reduction effects, meeting the equipment requirements associated with larger-scale unit operations as well as miniaturized, portable systems. Next, Donghai Petrochemical Refitting Company will continue to work with the Institute of Process Engineering of the Chinese Academy of Sciences to calibrate and verify the results of reactor model design calculations against actual experimental data. It will also further refine the design methods for radial reactors that are suitable for the various characteristics of reaction engineering and can take into account the properties of different catalysts. At the same time, it will upgrade the co-developed design software for coiled-tube heat exchangers and reactors.