Utjecaj geometrije mikroreaktora na promjer kapljica u emulziji ulje/voda

master's thesis

• Title (english): The influence of microreactors geometry on the droplet diameter of oil in water emulsions
• Author: Ivana Čulo
• Mentor: Tamara Jurina (mentor)
• Committee member: Ana Jurinjak Tušek (predsjednik povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Process Engineering); (Laboratory for Measurement, Regulation and Automatisation); Zagreb
• Defense date and country: 2020-07-17, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Cilj rada bio je ispitati utjecaj dvije različite geometrije mikroreaktora i promjene ukupnih protoka (20 – 280 μL minˉ¹) na pripremu i stabilnost emulzija ulje u vodi (U/V) u mikroreaktorskom sustavu. Za pripremu emulzija odabrani su neionski emulgatori (Tween 20 i PEG 2000) u koncentracijama 2 % i 4 %. Jedan od parametara procjene stabilnosti i određivanje svojstava emulzija je veličina kapljica disperzne faze u emulziji. Veličina kapljica emulzija analizirana je kao Feretov promjer. Minimalni prosječni Feretovi promjeri kapljica izmjereni su kod protoka 280 μL minˉ¹, u rasponu od 120,28 μm do 171,15 μm za mikroreaktor A s mikromiješalima u obliku viseće kapi te u rasponu od 132,03 μm do 189,1 μm za mikroreaktor B s vrtložnim mikromiješalima. Dodatno, razvijeni su modeli umjetnih neuronskih mreža za predviđanje veličina kapljica disperzne faze, na temelju ukupnih protoka zadanih u ovom radu. Dobiveni modeli imaju visoke vrijednosti koeficijenata determinacije za testiranje, učenje i validaciju uz male pogreške. Rezultati dobiveni primjenom umjetnih neuronskih mreža pokazali su se najpouzdanijim za predviđanje vrijednosti Feretovih promjera za emulgator PEG 2000 (2 %) u mikroreaktoru A uz koeficijent validacije R2 = 0,9999.

Abstract (english)

The aim of this study was to investigate the influence of two different microreactor geometries and changes of total flow rate (20 μL - 280 μL minˉ¹) on the preparation and stability of oil in water emulsions (O/W) in a microreactor system. Nonionic emulsifiers (Tween 20 and PEG 2000) at concentrations of 2 % and 4 % were selected for the emulsification. One of the parameters for stability assessment and determination of emulsion properties is the droplet size of the dispersed phase in the emulsion. The droplet size was analyzed as the Feret diameter. The minimum mean Feret droplet diameters were measured at 280 μL minˉ¹ ranging from 120,28 μm to 171,15 μm for the microreactor A with the teardrop micromixers and in the range from 132,03 μm to 189,1 μm for the microreactor B with the swirl micromixers. Additionally, Artificial Neural Networks models were developed to predict the droplet size of the dispersed phase based on the defined total flow rates. The obtained models have high values of determination coefficients for training, test, and validation, with small error values. The results obtained using Artificial Neural Networks were the most reliable for predicting the values of Feret diameters for emulsifier PEG 2000 (2 %) in microreactor A with validation coefficient R2= 0,9999.

• Keywords: mikroreaktor; Feretov promjer; emulzije ulje u vodi (U/V); umjetne neuronske mreže
• Keywords (english): microreactor; Feret diameter; oil in water emulsions (O/W); Artificial Neural Networks
• Language: croatian
• URN:NBN: urn:nbn:hr:159:612140
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-07-20 09:48:55