Photo-Optical In-Situ Measurement of Drop Size Distributions: Applications in Research and Industry

Abstract

-The exact knowledge of Drop Size Distributions (DSD) plays a major role in various fields of applications to control and optimise processes as well as reduce waste. In the microbial production of advanced biofuels, oil droplets are produced under turbulent conditions in an aqueous medium containing many surface active components, which might hinder the recovery of the product. Knowledge of DSD is thus essential for process optimisation. This study demonstrates the capability of a photo-optical measurement method for DSD measurement in fermentation broth and in plate separators aimed at cost reduction in the microbial production of advanced biofuels. Measurements were made with model mixtures in a bioreactor, and at the inlet and outlet of a plate separator. In the bioreactor, the method was effective in detecting a broad range of droplet sizes and in differentiating other disperse components (e.g. microbial cells and gas bubbles). In the plate separator, the method was effective in determining the influence of the varied parameters on the separation efficiency.Résumé -Mesure photo-optique in-situ de la distribution des taille des gouttes : applications dans la recherche et l'industrie -La connaissance approfondie de la distribution du diamètre des gouttelettes joue un rôle important dans des diverses applications des contrôles et d'optimisations des processus, de plus elle permet de réduire le gaspillage. Pendant la production microbienne de biocarburants avancés, des gouttelettes d'huiles sont produites sous les effets des turbulences du milieu aqueux contenant beaucoup de substances tensio-actives, ce qui pourrait entraver la récupération du produit. La connaissance de la distribution du diamètre des gouttelettes est donc essentielle pour l'optimisation des processus. Cette étude montre les possibilités offertes par une méthode de mesure photo-optique pour les mesures de la taille des gouttelettes dans des bouillons de fermentations et dans des séparateurs à plaques, ceci vise à réduire les coûts dans la production microbienne de biocarburants avancés. Les mesures ont été effectuées avec des mélanges modèles dans un bioréacteur ainsi qu'à l'entrée et à la sortie d'une plaque de séparation. Dans le bioréacteur, le procédé est efficace dans la détection d'une large gamme de tailles de gouttelettes et dans la différenciation des autres composants dispersés (par exemple des cellules microbiennes et des bulles de gaz). Dans le séparateur à plaque, le procédé est efficace, car il détermine l'influence de différents paramètres sur l'efficacité de la séparation.Oil & Gas Science and Technology -Rev. IFP Energies nouvelles (2017) 72, 14 Ó R.P. Panckow et al., published by IFP Energies nouvelles, 2017 DOI: 10.2516 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. LIST OF SYMBOLS AND/OR NOT...

Integration of Gas Enhanced Oil Recovery in Multiphase Fermentations for the Microbial Production of Fuels and Chemicals

“…Finally, further studies on the mechanism of oil recovery will allow for more robust design, achieving a compromise between fermentation and recovery requirements in terms of bubble size, number of bubbles, column geometry, residence time, and oil fraction. These studies require improving the acquisition of droplet size data, for example by implementing an in situ optical probe …”

“…These studies require improving the acquisition of droplet size data, for example by implementing an in situ optical probe. [27] From an operational perspective, an in-line GEOR column compared to an off-line separation at the end of the fermentation is more advantageous in cases where long fermentations runs are required (e.g., low productivity, or continuous fermentations). In these cases, prevention of emulsion stabilization over time, [28] or excessive accumulation of oil phase in the bioreactor [11] becomes more relevant.…”

Investigation and development of gravity separators with a standardized experimental setup

“…Figure shows an image as drops become visible as a shadow image and can be evaluated after binarization . The drops measured with the SOPAT probe (see Figure ) are recorded in incident light with a reflection surface (see Figure ) and the picture is then evaluated using an extended mathematical algorithm …”

“…[11,12] The drops measured with the SOPAT probe (see Figure 5) are recorded in incident light with a reflection surface (see Figure 6) and the picture is then evaluated using an extended mathematical algorithm. [13,14] The dispersion unit ( Figure 7) with a maximum of two perforated plates generates different DSD when using plates Figure 8) allowing us to observe the behaviour of the dispersion in a discontinuous experiment. The cell is made of glass, has a diameter of 80 mm and the lids are made of polytetrafluorethylene (PTFE) and stainless steel.…”

“…The following image analysis from a sample, as depicted in Figure 9, allows the automatic detection of the coalescence and sedimentation curves (Figure 1), according to the defined grey level value. [13] F I G U R E 7 Dispersion unit (CAD exploded view)…”