Batch-to-batch iterative learning control of a fed-batch fermentation process using batchwise linearised models identified from process operation data is presented in this paper. Due to model-plant mismatches and the present of unknown disturbances, off-line calculated control policy may not be optimal when implemented to the real process. The repetitive nature of batch process allows informati...

BACKGROUND Fungal morphology and aeration play a significant role in the growth process of Mortierella alpina. The production of microbial oil rich in arachidonic acid (ARA) in M. alpina was enhanced by using a multi-stage fermentation strategy which combined fed-batch culture with precise control of aeration and agitation rates at proper times. RESULTS The fermentation period was divided int...

Apple pomace extract (APE) in aerobic variable fed batch culture under standardized fermentation parameters was evaluated for the production of baker’s yeast. The substrate was fed at a flow rate of 0.39 dm h to regulate fermentable sugar concentration between 1-2 % in bioreactor. An average specific growth rate of 0.24 h and cellular yield coefficient of 0.48 g/g sugar was obtained during bake...

BACKGROUND To make lignocellulosic fuel ethanol economically competitive with fossil fuels, it is necessary to reduce the production cost. One way to achieve this is by increasing the substrate concentration in the production process, and thus reduce the energy demand in the final distillation of the fermentation broth. However, increased substrate concentration in simultaneous saccharification...

This report describes the building of a simulator for prediction of the dissolved oxygen concentration, the oxygen transfer rate and the concentration of carbon dioxide in a fermentation process. The steady state models were made using the linguistic equations method. The dynamic models were made using Simulink ® toolbox in the Matlab ® . At the beginning, some basics about fermentation and mic...

Unbleached pulp from the pulp and paper industry was used as a cellulosic material source to produce bioethanol in a separate hydrolysis and fermentation process. In the batch enzymatic saccharification, three cellulolytic enzymes and different initial carbohydrate (CH) contents were tested. Cellic CTec2 was shown to be the most efficient enzyme with the lowest dosage used: 35 FPU gCH . Sugar p...

In this study, a mathematical model was proposed and the accuracy of this model was assessed to predict the growth of Pseudomonas aeruginosa and rhamnolipid production under nitrogen limiting (sodium nitrate) fed-batch fermentation. All of the parameters used in this model were achieved individually without using any data from the literature. The overall growth kinetic of the strain was evaluat...

There are three variations of the fermentation process. In batch fermentation, a sterilized nutrient solution in the fermentor is inoculated with micro-organisms and incubation is allowed to proceed. During the course of the fermentation, oxygen is added (as in the case of aerobic microorganisms) and an acid or base to control the pH. The composition of the culture medium, the biomass concentra...

Fed-batch culture is often used in industry, and dissolved oxygen (DO) concentration control is important in fermentation process control. DO control is often applied by using feedback (FB) control strategy. But, feedforward-feedback (FFFB) control has the advantage in dealing with the time-varying characteristics resulting from cell growth during the fermentation process. Mathematical modeling...