Figure 17. The water-steam distillation method by cohobation for
extraction essential oil [114].
There is other type of continuous systems known as continuous systems.
In the late 20th century, essential oil producers were forced to load
and unload steel after loading and finishing the process regularly. So
they set out to create a process that could produce essential oils
continuously. In such a way that plant materials are slowly loaded into
the upper steel and exit from the bottom. In this method, the whole
biomass is in contact with steam and ensures the optimal extraction of
essential oil. This method is not suitable for inflorescences, fruits
and roots [9].