Inst. Prozess- und Verfahrenstechnik

129 Items

Recent Submissions
Experimentelle Analyse und Modellierung des Stofftransportes durch Kohlenstoffmembranen bei der Hochdruckgastrennung

Kruse, Nicolas (2018)

Obwohl die Gastrennung mit Kohlenstoffmembranen mittlerweile ein etabliertes Gebiet der Membranforschung darstellt und Kohlen-stoffmembranen generell geeignet für den Einsatz unter Hochdruckbedingungen sind, liegen bisher nur wenige Veröffentlichungen zur Untersuchung ihres Trennverhaltens oberhalb von 2 MPa vor. Auch die etablierten Stofftransportmodelle zur Beschreibung von porösen Membranen ...

Effect of dispersed hydrophilic silicon dioxide nanoparticles on batch adsorption of benzoic acid from aqueous solution using modified natural vermiculite: An equilibrium study

Pouya, Ehsan Sadeghi ; Abolghasemi, Hossein ; Fatoorehchi, Hooman ; Rasem, Bettina ; Hashemi, Seyed Jalaledin (2016-10-11)

The equilibrium adsorption of benzoic acid from an aqueous medium on a natural vermiculite-based adsorbent was studied in the presence and absence of hydrophilic silicon dioxide nanoparticles in batchwise mode. The adsorbent was prepared through grinding natural vermiculite in a laboratory vibratory disk mill and the surfactant modification of ground vermiculite by cetyltrimethylammonium bromid...

Entwicklung eines Prototyps zur dynamischen Fließschemasimulation von Prozessen der Aufbereitung gemischter Siedlungsabfälle

Platzk, Stefan (2018)

Die vorliegende Arbeit befasst sich mit der Erschaffung und exemplarischen Anwendung eines Prototyps zur Modellierung und dynamischen Fließschemasimulation von Abfallbehandlungsverfahren. Zur Eingrenzung des Betrachtungsrahmens wird einführend der Wissensstand zum Stoffsystem „Gemischte Siedlungsabfälle“ zusammengetragen. Neben den jährlich in Deutschland anfallenden Mengen und erzielten Verwer...

Geregelte Strömungskontrolle einer Statorkaskade mit Seitenwand- und Hinterkantenaktuation

Kiesner, Matthias (2018)

Die Steigerung des Wirkungsgrades von Gasturbinen ist ein wichtiges Entwicklungs- und Forschungsziel. Durch die große Stückzahl der weltweit im Energie- und Transportsektor eingesetzten Gasturbinen ist das Potential für eine Reduktion der Treibhausgasemissionen enorm. Aktuell wird eine neue Technologie erforscht, die einen Wechsel von der konventionellen isobaren Verbrennung zu einer isochoren ...

Energieeffiziente Gärrestaufbereitung

Gienau, Tobias (2018)

Aufgrund der zunehmenden Überdüngung landwirtschaftlicher Flächen durch Wirtschaftsdünger und Gärreste aus Biogasanlagen wird eine ökonomische und ökologische Vollaufbereitungstechnik zur Separation der Nährstoffe und zur Gewinnung von Prozesswasser aus Gärresten und Güllen benötigt. Das Vollaufbereitungsverfahren zur Düngemittelrückgewinnung durch mehrstufige Fest-/ Flüssigtrennung und Membran...

Learning control algorithms for an unsteady stator vane flow field

Steinberg, Simon Johannes (2018)

This thesis contributes to the field of active flow control of aerodynamically highly loaded compressors. In particular, the periodically disturbed and thus unsteady flow field of an experimental, rectilinear compressor stator cascade with multiple active flow control devices is subject of the investigation. Researching such a configuration is the conclusive step to recent research activities a...

Modelling of coalescence in turbulent liquid/liquid dispersions considering droplet charge

Kamp, Johannes ; Nachtigall, Stephanie ; Maaß, Sebastian ; Kraume, Matthias (2012)

Drop size distributions in liquid/liquid systems within a turbulent flow, being an integral part of many technical applications, can be simulated solving population balance equations. Experimental investigations in stirred toluene/water systems at constant ionic strength of 0.1 mol/L showed that with pH values higher than 11, coalescence is hindered considerably due to electrostatic effects. Wi...

Influence of drop size and superimposed mass transfer on coalescence in liquid/liquid dispersions - Test cell design for single drop investigations

Kamp, Johannes ; Kraume, Matthias (2014)

The detailed understanding of droplet coalescence is important for the accurate description of liquid/liquid dispersions. A test cell is designed which enables serial examinations of the random coalescence process with high repetition rate, good observability and accuracy of experimental parameters. Within this rectangular test cell a rising droplet collides with a pendant one, while recorded b...

Coalescence efficiency model including electrostatic interactions in liquid/liquid dispersions

Kamp, Johannes ; Kraume, Matthias (2015)

The drop size distribution is an essential process variable in liquid/liquid systems and relevant in many technical applications. It can be described by population balance equations. A coalescence efficiency model was developed to be able to describe the well-known coalescence inhibition due to changing pH value or salt concentration. The model includes the attractive van der Waals and repulsiv...

Automated image analysis for trajectory determination of single drop collisions

Kamp, Johannes ; Hänsch, Ronny ; Kendzierski, Gregor ; Kraume, Matthias ; Hellwich, Olaf (2016)

The fundamental analysis of drop coalescence probability in liquid/liquid systems is necessary to reliably predict drop size distributions in technical applications. For this crucial investigation two colliding oil drops in continuous water phase were recorded with different high speed camera set-ups under varying conditions. In order to analyze the huge amount of recorded image sequences with ...

From single drop coalescence to droplet swarms - Scale-up considering the influence of collision velocity and drop size on coalescence probability

Kamp, Johannes ; Kraume, Matthias (2016)

Coalescence modelling in liquid/liquid dispersions is a challenging task and field of investigations up to now, which becomes apparent when comparing the various existent models with their different and partly even contradictive implementation of influencing factors. In this work, systematic investigations of single drop coalescence were used to compare and validate different coalescence effici...

Drop coalescence in technical liquid/liquid applications

Kamp, Johannes ; Villwock, Jörn ; Kraume, Matthias (2016)

The coalescence phenomenon of drops in liquid/liquid systems is reviewed with particular focus on its technical relevance and application. Due to the complexity of coalescence, a comprehensive survey of the coalescence process and the numerous influencing factors is given. Subsequently, available experimental techniques with different levels of detail are summarized and compared. These techniqu...

Systematic coalescence investigations in liquid/liquid systems

Kamp, Johannes (2017)

Liquid/liquid dispersions, which are mixtures of (nearly) immiscible liquids, are an integral part of many technical processes and everyday consumer products. For example, in technical processes the interfacial area is increased by dispersion to enhance mass and heat transfer; or consumer products like lotions and creams consist of stabilised oil/water dispersions. The process efficiency and re...

Toward microbioreactor arrays

Glauche, Florian ; John, Gernot T. ; Arain, Sarina ; Knepper, Andreas ; Neubauer, Antje ; Goelling, Detlef ; Lang, Christine ; Violet, Norman ; King, Rudibert ; Neubauer, Peter (2015)

In this study, a slow-responding chemo-optical sensor for dissolved oxygen (DO) integrated into a 96-well plate was developed. The slow response time ensures that the measured oxygen value does not change much during plate transport to the microplate reader. The sensor therefore permits at-line DO measurement of microbial cultures. Moreover, it eliminates the necessity of individual optical mea...

Development of a method for reliable power input measurements in conventional and single-use stirred bioreactors at laboratory scale

Kaiser, Stephan Christian ; Werner, Sören ; Jossen, Valentin ; Kraume, Matthias ; Eibl, Dieter (2017)

Power input is an important engineering and scale-up/down criterion in stirred bioreactors. However, reliably measuring power input in laboratory-scale systems is still challenging. Even though torque measurements have proven to be suitable in pilot scale systems, sensor accuracy, resolution, and errors from relatively high levels of friction inside bearings can become limiting factors at small...

Einsatz von Schlüsselindikatoren zur Berücksichtigung unsicherer Randbedingungen in der Anlagenführung

Werk, Sebastian (2017)

Produktionsprozesse in der chemischen Industrie werden von Operateuren in Leitwarten überwacht und gesteuert. Den Produktionsprozessen liegen komplexe dynamische Modelle zugrunde. Die Zielstellung der Operateure besteht darin, die Prozesse hinsichtlich verschiedener, sich teilweise widersprechender Ziele wie Wirtschaftlichkeits- und Qualitätsanforderungen zu steuern. Hierbei stehen oftmals üb...

Post-mining water treatment

Hoyer, Michael (2017)

Nanofiltration of real uranium-contaminated mine drainage was successfully discussed in experiments and modeling. For the simulation a renowned model was adapted that is capable of describing multi-component solutions. Although the description of synthetic multi-component solutions with a limited number of components was performed before, the results of this work show that the adapted model is ...

Löslichkeitsselektive Mixed Matrix Membranen zur Gaspermeation

Kramer, Verena (2017)

In this work solubility selective mixed matrix membranes consisting of silicon polymers and activated carbon are investigated for transport and separation properties of n-butane and methane. For mathematical description of the permeation process a new model is developed based on one-dimensional discretisation of the separation layer. This is an innovative approach for modelling of mixed matrix ...

Systematic evaluation of ill-posed problems in model-based parameter estimation and experimental design

López Cárdenas, Diana Carolina (2016)

The lack of informative experimental data, the complexity of first-principles models, over-parameterization and parameter correlations make, among others, the recovery of kinetic, transport, and thermodynamic parameters complicated. These issues are sources of non-identifiability and consequently ill-posedness. This research investigates the features, sources, effects and treatments of ill-pose...

Characterization and validation of the high accurate heat meter calibration facility of the Physikalisch-Technische Bundesanstalt PTB

Cordova Murillo, Moritz Leopoldo (2016)

Flow rate calibration facilities have the task to establish a flow rate under predefined conditions and to measure this flow rate within a declared uncertainty. To proof the correctness of the declared uncertainty requires in depth understanding of every hardware component. In cases where those components can not be directly isolated and modeled it is necessary to make assumptions and to make e...