Читать книгу Liquid Biofuels - Группа авторов - Страница 50

Sonochemistry induced by cavitational phenomena and its beneficial application for biodiesel production has attracted the interest of the research community and the industrial domain. Nevertheless, the complex design of the system and its effective implementation in a large-scale process still needs significant R&D efforts. The principal merit of cavitational reactors for biodiesel synthesis at a commercial scale is its reduced operational cost (in terms of energy requirement) and higher energy efficiencies and yields. In lab-scale studies, exergy analysis looks promising, but translating these ideas into commercial processing is still a challenge [119]. As discussed in the previous section, the two types of pilot-scale reactors have been designed, viz., multi-frequency sonochemical reactors and hydrodynamic cavitation reactors. The research group of Pandit and Gogate has demonstrated the successful application of pilot-scale hydrodynamic cavitational reactors for biodiesel synthesis in numerous studies [23, 97, 120]. These reactors achieve higher conversation rates in a shorter time and reduce solvent requirements compared to conventional mechanical mixing. However, these reactors are not compatible with the heterogeneous catalysts. This doesn’t improve the downstream processing of biodiesel, and thus becomes the main limitation in scale-up. The multi-frequency sonochemical reactors will be an ideal solution in such cases, but limited case studies have been carried out using such reactors. The main advantages of such reactors are their flexibility of operation in both batch and continuous model and the compatibility with heterogeneous catalysts. On the other hand, the high energy input of these reactors is the major limiting factor [79, 114, 121]. Murillo et al. [122] and others [86] have successfully demonstrated 3 L capacity ultrasonic reactor for biodiesel synthesis. Comprehensive work is still required to achieve the commercialization of biodiesel production.