Scale up and design of processes in aerated-stirred fermenters for the industrial production of vinegar

A scale-up methodology was applied to the model previously developed for the industrial production of vinegar in an aerated-stirred pilot fermenter. The response surfaces generated by the model demonstrated that aerated mechanical power input, superficial air velocity, temperature, hydrostatic pressure and concentrations of compounds must be kept in the industrial-scale fermenters with the same geometry dimensions as the pilot fermenter. These variables maintain the values of kLa  , CO2,L∗ and OTRmax and asses the same effects of hydrodynamics and oxygen transfer, allowing the values of the process variables of the industrial-scale fermenters to be scaled down to the values of the pilot fermenter, which are required for applying the models. On these bases, a Simulation Environment for Acetification Processes (SEAP) was developed to design industrial processes on any scale and to predict the behaviour of fermentations and the costs of vinegar production. Finally, an example of the design and optimisation of a fermentation process with SEAP is reported, applying an optimisation methodology based on response surfaces and genetic algorithms using a desirability function as the response.