dc.description.abstract | There are little amounts of literatures related to reactive dividing wall column(RDWC) to date. But from the already published literatures, before designing a reactive
dividing wall column, a configuration with reactive distillation system(RD system) needs to be studied, then thermally integrating the system. It will help in efficiently using the reactive dividing wall column to bring about a saving in energy.This research is based on the work of Lee et al.[16] which focuses on the
esterification of alcohol mixtures of butanol and pentanol, using the concept of reaction
first then separation. There are two types of configurations in which are direct sequence
and indirect sequence–aqueous reflux in their work. We not only use the above as the
foundation of the reactive dividing wall column design, but also minimize the total
annual cost (TAC) to find the optimum design. Comparison of the pros and cons
between the two configuration of esterification of butanol and pentanol system and
esterification of pentanol and hexanol system has been conducted. The results show that
in the esterification of pentanol and hexanol system that the separation of acetic acid
and butyl acetate is hard to separate in the direct system, in order to maintain the
product specification of acetic acid in the bottoms requires a lot of trays. Therefore the
indirect sequence-aqua phase reflux is more competitive. But in the esterification of
pentanol and hexanol system, ignoring the problem relating to the limit in separation of
acetic acid and butyl acetate, so the column doesn’t need that much amount of trays to
maintain the product specifications. Even though the direct sequence has a remixing
effect of the two esters in the bottom of the reactive distillation column, using a reactive
dividing wall column design is more competitive.
In the dynamic simulation, the pentanol and hexanol system in the direct sequence
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after integration is studied, due to the limit of the open loop sensitivity analysis, the
choice of control points are affected, causing the product specification to have small
deviations under disturbances. Also, under throughput disturbances, the conversion also
dropped, affecting the product specifications. But in the end of the disturbances test,
only some of the disturbances causes a large deviation to the product specification, the
rest of the disturbances shows only a 0.1mol% deviation. | en |