Lactic acid is commonly used in a
wide range of fields, such as
cosmetics, pharmaceutical products, chemistry, and food. During recent
years, its use for new applications, such as the production of biodegradable
and biocompatible polymers, green solvents, and oxygenated chemicals,
have received considerable attention. However, the relatively high
production cost of lactic acid hinders many large-scale applications.
It is necessary to develop more efficient methods of separation and
purification to cheapen lactic acid production processes. The main
objective of this study is to investigate the use of process intensification,
particularly the reactive distillation process, for a sustainable
purification of lactic acid. To do so, there have been proposed, on
the one hand, four intensified alternatives in which synthesis and
design are based on thermal couplings and, on the other hand, three
alternatives looking for water mass integration. Design and optimization
of those modified configurations are carried out employing a stochastic
optimization method, using as objective functions some metrics associated
with the concept of sustainability (economics, environmental, and
inherent safety indexes). A study on the dynamic performance of the
configurations through the use of singular value decomposition is
carried out in a complementary way. The results in the first redesign
stage show improvements in all performance indexes. However, a great
difference between the implementation of a thermal coupling that substitutes
a condenser instead of a reboiler has been identified. The best scheme,
based on a sustainability framework, resulted in a modified process,
including a dividing wall column-based scheme.