Koichi Iwakabe1, Keigo Matsuda2, Masaru Nakaiwa3, Kinpei Horiuchi4, Toshinari Nakanishi5, Akio Horiguchi6, Kazuya Kubo6, Takao Ohmori1, Takuji Yamamoto1, and Sho Kataoka1. (1) Energy-Efficient Chemical Systems Group, Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Japan, AIST Tsukuba Central 5, 1-1-1, Higashi, Tsukuba-shi, Ibaraki, 305-8565, Japan, (2) Department of Chemistry and Chemical Engineering, Graduate School of Science and Engineering, Yamagata University, 4-3-16, Jonan, Yonezawa, 992-8510, Japan, (3) Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Japan, AIST Tsukuba Central 5, 1-1-1, Higashi, Tsukuba-shi, Ibaraki, 305-8565, Japan, (4) Project Development Department, Maruzen Petrochemical Co., Ltd., 3, Goi, Minami-kaigan, Ichihara-shi, Chiba, 290-8503, Japan, (5) Kimura Chemical Plants Co. Ltd., 2-1-2, Terajima Kuise, Amagasaki-shi,, Hyogo, 660-8567, Japan, (6) R&D Division, Mitsubishi Chemical Group Science and Technology Research Center, Inc., 1, Tohocho, Yokkaichi-shi, Mie, 510-8530, Japan
Distillation is the most widely-used but the most energy-consuming separation process in chemical industries. The internally Heat-Integrated Distillation Columns (HIDiC) are one of the most promising technologies for the energy saving of conventional distillation processes. HIDiCs have similar structure to a heat exchanger. The rectifying section of HIDiCs is contacted with the stripping section through walls for heat exchange between these two sections. If temperatures of the rectifying section are higher than those of the stripping section, the residual heats in the rectifying section can be utilized in the stripping section. If the coupling of these two sections is appropriate, it will work like well-controlled side heaters/coolers. The HIDiC technology attracts a lot of industrial and academic interests since the energy savings performance of the HIDiC has been proved by the pilot plant in Japan. Although a lot of operation data of the HIDiC pilot plant have been already obtained, the mass and heat transfer phenomena in the HIDiC are still unclear. In order to analyze the phenomena, a simulator with rate-based model has been developed for HIDiCs. Simulation results showed that the separation performance of the HIDiC is affected by the internal heat exchange. The results also suggested that the internal heat exchange might suppress the mass transfer. Here we report significant outcomes from the study.