Bioethanol production using different intermediates of sugar beet processing and bioprocesses mathematical modelling

U sklopu disertacije proučavana je proizvodnja etanola pomoću kvasca Saccharomyces cerevisiae na međuproduktima prerade šećerne repe (svježi sok šećerne repe i svježi repini rezanci). Proizvodnja etanola na svježem soku provedena je u bioreaktoru s mješalom korištenjem različitih tehnika uzgoja: šaržni, šaržni s pritokom i polukontinuirani postupkak. Za opis ovih bioprocesa razvijeni su matematički modeli koji uspješno opisuju eksperimentalne podatke. Proizvodnja etanola na svježim repinim rezancima provedena je u novom tipu HRCB-a. U ovom dijelu istraživanja proučavan je utjecaj operacijskih parametara bioreaktora kao što su način rotacije (povremena, konstantna i intervalna rotacija) i brzina rotacije bioreaktora (5-15 min-1), te utjecaj korisnog volumena bioreaktora (VK/VU = 0,20-0,70) na tijek bioprocesa proizvodnje etanola u HRCB-u. Najveće vrijednosti pokazatelja uspješnosti bioprocesa proizvodnje etanola ostvarene su kod intervalne rotacije (12 min/h, 15 min-1 i 0,20 VK/VU) (YP1/S = 0,47 g g-1, E = 88,10% i Pr = 0,618 g L-1 h-1). Na kraju ovog istraživanja formiran je matematički model za opis bioprocesa proizvodnje etanola u HRCB-u.Short abstract: In this investigation production of ethanol from intermediates of sugar beet processing (raw sugar beet juice and raw sugar beet cossetts) by using yeast Saccharomyces cerevisiae was studied. All experiments with raw sugar beet juice were performed in stirred tank bioreactor. In this investigation different cultivation techniques were used: batch , fed batch and repeated batch. For each cultivation technique mathematical model was developed for description of bioprocess performance. Ethanol production from raw sugar beet cossettes was performed in a new type of HRTB. In this part of investigation the impact of different bioreactor operational parameters [type of rotation (periodical, constant and interval), bioreactor rotation speed (5-15 min-1) and working volume of bioreactor (VW/VT = 0,20-0,70)] on the ethanol production in the HRTB was studied. The highest bioprocess efficiency parameters (YP1/S = 0,47 g g-1, E = 88,10% and Pr = 0,618 g L-1h-1) were observed by the following combination of bioreactor operational parameters: 12 min/h, 15 min-1 and VW/VT = 0,20. At the end of this research mathematical model of ethanol production in the HRTB was developed