A mini-module with built-in spacers for high-throughput ultrafiltration

Ultrafiltration membrane modules suffer from a permeate flow decrease arising during filtration and caused by concentration polarization and fouling in, e.g., fermentation broth purification. Such performance losses are frequently mitigated by manipulating the hydrodynamic conditions at the membrane-fluid interface using, e.g., mesh spacers acting as static mixers. This additional element increases manufacturing complexity while improving mass transport in general, yet accepting their known disadvantages such as less transport in dead zones. However, the shape of such spacers is limited to the design of commercially available spacer geometries. Here, we present a methodology to design an industrially relevant mini-module with an optimized built-in 3D spacer structure in a flat-sheet ultrafiltration membrane module to eliminate the spacer as a separate part. Therefore, the built-in structures have been conceptually implemented through an in-silico design in compliance with the specifications for an injection molding process. Ten built-in structures were investigated in a digital twin of the mini-module by 3D-CFD simulations to select two options, which were then compared to the empty feed channel regarding mass transfer. Subsequently, the simulated flux increase was experimentally verified during bovine serum albumin (BSA) filtration. The new built-in sinusoidal corrugation outperforms conventional mesh spacer inlays by up to 30% higher permeation rates. The origin of these improvements is correlated to the flow characteristics inside the mini-module as visualized online and in-situ by low-field and high-field magnetic resonance imaging velocimetry (flow-MRI) during pure water permeation

A scalable bubble-free membrane aerator for biosurfactant production

The bioeconomy is a paramount pillar in the mitigation of greenhouse gas emissions and climate change. Still, the industrialization of bioprocesses is limited by economical and technical obstacles. The synthesis of biosurfactants as advanced substitutes for crude-oil-based surfactants is often restrained by excessive foaming. We present the synergistic combination of simulations and experiments towards a reactor design of a submerged membrane module for the efficient bubble-free aeration of bioreactors. A digital twin of the combined bioreactor and membrane aeration module was created and the membrane arrangement was optimized in computational fluid dynamics studies with respect to fluid mixing. The optimized design was prototyped and tested in whole-cell biocatalysis to produce rhamnolipid biosurfactants from sugars. Without any foam formation, the new design enables a considerable higher space-time yield compared to previous studies with membrane modules. The design approach of this study is of generic nature beyond rhamnolipid production

Reseña de El teatro chaqueño de las crueldades. Memorias qom de la violencia y el poder. Florencia Tola y Valentín Suarez (Comp.). Ciudad Autónoma de Buenos Aires: Rumbo Sur/ethnographica. Resistencia: Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET). Instituto de Investigaciones Geohistóricas (IIGHI). Nanterre: Centro EREA del LESC (CNRS), 2016, 200 páginas

En El teatro chaqueño de las crueldades. Memorias qom de la violencia y el poder, Florencia Tola y Valentín Suarez compilan historias narradas por hombres y mujeres qom de Riacho de Oro, Barrio Nam Qom y San Carlos en la provincia de Formosa, y Olla Quebrada y Río Muerto Cruz en la provincia de Chaco: Valentín Suarez, Timoteo Francia, Ernesto Segundo, Asunción Ceferino, Federico Gómez, Félix Suarez, Pablo Floricel, Eduardo Mansilla, Juan Rivero, Laureano Méndez, y Carlos Torrent. Estas histor..

A scalable bubble‐free membrane aerator for biosurfactant production

The bioeconomy is a paramount pillar in the mitigation of greenhouse gas emissions and climate change. Still, the industrialization of bioprocesses is limited by economical and technical obstacles. The synthesis of biosurfactants as advanced substitutes for crude-oil-based surfactants is often restrained by excessive foaming. We present the synergistic combination of simulations and experiments towards a reactor design of a submerged membrane module for the efficient bubble-free aeration of bioreactors. A digital twin of the combined bioreactor and membrane aeration module was created and the membrane arrangement was optimized in computational fluid dynamics studies with respect to fluid mixing. The optimized design was prototyped and tested in whole-cell biocatalysis to produce rhamnolipid biosurfactants from sugars. Without any foam formation, the new design enables a considerable higher space-time yield compared to previous studies with membrane modules. The design approach of this study is of generic nature beyond rhamnolipid production

Hands-on Kinetic Measurements and Simulation for Chemical Process Engineering Students

Hands-on experience in the laboratory is essential in chemical engineering education to enhance the understanding of abstract theories and their effect on chemical processes. In this work, we describe a laboratory class, which combines some of the main engineering concepts into a set of hands-on experiments and simulations. Students are introduced to an iodine clock reaction performed in multiple different reactor types and are instructed to determine the reaction kinetics. Subsequent analysis of the experimental data in Python teaches basic programming skills and the concepts of numeric integration and optimization. Finally, a digital twin of one of the reactors is developed in COMSOL Multiphysics to give the students an application-focused introduction to more-dimensional multiphysics modeling. The students thereby get practical insights into the different methods and stages of reactor and reaction engineering. Based on the students' assignments, we consistently see a deeper understanding of reaction kinetics and reactor engineering than in the accompanying traditional lecture