FG Dynamik und Betrieb technischer Anlagen

38 Items

Recent Submissions
Optimal Control of Droplets on a Solid Surface Using Distributed Contact Angles

Bonart, Henning ; Kahle, Christian ; Repke, Jens-Uwe (2020-07-06)

Controlling the shape and position of moving and pinned droplets on a solid surface is an important feature often found in microfluidic applications. However, automating them, e.g., for high-throughput applications, rarely involves model-based optimal control strategies. In this work, we demonstrate the optimal control of both the shape and position of a droplet sliding on an inclined surface. ...

A pressure-driven, dynamic model for distillation columns with smooth reformulations for flexible operation

Hoffmann, Christian ; Weigert, Joris ; Esche, Erik ; Repke, Jens-Uwe (2020-08-17)

Dynamic models for plants including the startup or shutdown phase are still scarce as the (dis-)appearence of phases or streams is challenging to implement. We present an approach to model a distillation column, in which these operation modes are also considered without exchanging equations. For this purpose, the well-known modeling equations for distillation columns are reformulated robustly t...

Rigorous analysis of reactive microemulsion systems for process design and operation

Illner, Markus (2020)

In recent years, significant effort towards more sustainable chemical processes and products is noticeable in both academia and industry. Hence, process development and operation aim for the implementation of new synthesis paths for emerging renewable feedstocks and waste prevention. However, industrial realization of developed process concepts is often enough challenging due to their novelty, ...

Investigation on the simultaneous removal of COS, CS2 and O2 from coke oven gas by hydrogenation on a Pd/Al2O3 catalyst

Kamp, Eva ; Thielert, Holger ; Morstein, Olaf von ; Kureti, Sven ; Schreiter, Norman ; Repke, Jens-Uwe (2020-04-07)

The present study deals with the processing of coke oven gas mainly composed of H2, CH4, N2 and CO to provide a feedstock for the synthesis of base chemicals. In this respect, the particular focus of this work is the simultaneous reduction of critical trace components like COS, CS2 and O2 by catalytic reaction with H2. The investigations were performed in synthetic coke oven exhaust using a Pd/...

Multi-Scale Analysis of Integrated C1 (CH4 and CO2) Utilization Catalytic Processes: Impacts of Catalysts Characteristics up to Industrial-Scale Process Flowsheeting, Part II: Techno-Economic Analysis of Integrated C1 Utilization Process Scenarios

Godini, Hamid Reza ; Azadi, Mohammadreza ; Khadivi, Mohammadali ; Schomäcker, Reinhard ; Gallucci, Fausto ; Wozny, Günter ; Repke, Jens-Uwe (2020-04-30)

In the second part of this paper (Part II), the potentials and characteristics of an industrial-scale Oxidative Coupling of Methane (OCM) process integrated with CO2-hydrogenation, ethane dehydrogenation, and methane reforming processes are highlighted. This novel process concept comprises a direct conversion of methane to ethane and ethylene and further conversion of the resulted carbon dioxid...

Multi-Scale Analysis of Integrated C1 (CH4 and CO2) Utilization Catalytic Processes: Impacts of Catalysts Characteristics up to Industrial-Scale Process Flowsheeting, Part I: Experimental Analysis of Catalytic Low-Pressure CO2 to Methanol Conversion

Godini, Hamid Reza ; Khadivi, Mohammadali ; Azadi, Mohammadreza ; Görke, Oliver ; Jazayeri, Seyed Mahdi ; Thum, Lukas ; Schomäcker, Reinhard ; Wozny, Günter ; Repke, Jens-Uwe (2020-05-04)

A multi-aspect analysis of low-pressure catalytic hydrogenation of CO2 for methanol production is reported in the first part (part I) of this paper. This includes an extensive review of distinguished low-pressure catalytic CO2-hydrogenation systems. Specifically, the results of the conducted systematic experimental investigation on the impacts of synthesis and micro-scale characteristics of the...

Uncertainty Analysis for Data-Driven Chance-Constrained Optimization

Häußling Löwgren, Bartolomeus ; Weigert, Joris ; Esche, Erik ; Repke, Jens-Uwe (2020-03-20)

In this contribution our developed framework for data-driven chance-constrained optimization is extended with an uncertainty analysis module. The module quantifies uncertainty in output variables of rigorous simulations. It chooses the most accurate parametric continuous probability distribution model, minimizing deviation between model and data. A constraint is added to favour less complex mod...

A Numerical Implementation of the Soret Effect in Drying Processes

Häussling Löwgren, Bartolomeus ; Bergmann, Julius ; Alves-Filho, Odilio (2020-02-17)

Drying of porous media is strictly governed by heat and mass transfer. However, contrary to the definition that drying is simultaneous transport mechanisms of heat and mass, most past and current models either account for temperature or concentration gradient effects on drying. Even though the complexity of computations of these processes varies with area of application, in most cases, the Dufo...

Evaluation of different pre-treatments of chromium leather waste and their use in biogas production

Scaraffuni Gomes, Carolina (2020)

The worldwide economic importance of the leather industry is undeniable, as it converts a by-product of the meat industry, the hides, into a value-added product. However, processing of leather generates thousands of tons of new solid waste annually and, unlike hides, this waste has a low biodegradability. Usually, the tanning process is carried out using basified trivalent chromium salts. As a ...

MOSAICmodeling PlantDesign

Fillinger, Sandra (2020)

Considering the volatile macro-economic environment aggravating competitiveness in the increasingly globalizing market the most important challenge facing industrial companies is to achieve an innovation lead with high quality and reliability with shortened innovation cycles. For the entire life cycle of chemical plants, several stakeholders, such as owners, operators, vendors, and contractors,...

Kinetische Parameteridentifikation und Modelldiskriminierung am Beispiel der nassen Oxidation von Thiosulfat

Holz, Stephan ; Stewers, Lennart ; Thielert, Holger ; Guetta, Zion ; Repke, Jens‐Uwe (2019-12-02)

In der Kokereitechnik fallen belastete Abwässer an, die effizient behandelt werden müssen, um die Umwelt nicht zu belasten und den gesetzlichen Verordnungen gerecht zu werden. Hierzu ist ein genaues Prozessverständnis notwendig. Aufgrund der Vielzahl an möglichen Modifikationen nehmen Schwefelverbindungen eine Sonderstellung ein, weswegen die Kenntnis der verschiedenen Reaktionspfade und ‐kinet...

Investigation of the Degradation of Chelate Complexes in Liquid Redox Desulfurization Processes

Holz, Stephan ; Köster, Peter ; Thielert, Holger ; Guetta, Zion ; Repke, Jens-Uwe (2020-01-22)

Metal complexes such as Fe‐EDTA, which are used as pseudo‐catalysts or oxygen carriers in wet oxidative desulfurization processes, are subject to a degradation mechanism that significantly influences the economics of such processes. Therefore, this study presents a methodology for determining the degree of degradation during the reactive hydrogen sulfide absorption in a Fe‐EDTA solution within ...

Heat transfer between a rolling sphere and a solid wall

Brösigke, Georg Tobias (2020)

The heat transfer between particles and walls has been topic of research for several decades. In most cases existing correlations were developed empirically for special conditions and applications like fluidised beds or rotary kilns. With a deeper fun- damental understanding of the occurring heat transfer mechanisms both design of existing and development of innovative apparatuses, could be mor...

Controlling sliding droplets with optimal contact angle distributions and a phase field model

Bonart, Henning ; Kahle, Christian ; Repke, Jens-Uwe (2019-11-18)

We consider the optimal control of a droplet on a solid by means of the static contact angle between the contact line and the solid. The droplet is described by a thermodynamically consistent phase field model from [Abels et al., Math. Mod. Meth. Appl. Sc., 22(3), 2012] together with boundary data for the moving contact line from [Qian et al., J. Fluid Mech., 564, 2006]. We state an energy stab...

Planare Laserinduzierte Fluoreszenz zur experimentellen Analyse des Gastransports in Filmströmungen in Anwesenheit einer einzelnen Mikrostruktur

Kapoustina, Viktoria (2019)

Im Rahmen der vorliegenden Arbeit wird, nach Wissen des Autors, erstmalig der Einfluss einer einzelnen Mikrostruktur auf den lokalen Gas-Flüssig-Stofftransport experimentell beschrieben. Damit ist die Arbeit klar abzugrenzen von experimentellen Studien anderer Forschungsgruppen, die sich bislang ausschließlich mit der Analyse integraler Stofftransport-Parameter beschäftigen. Eine nicht-invasive...

Towards demand-side management of the chlor-alkali electrolysis: Dynamic, pressure-driven modeling and model validation of the 1,2-dichloroethane synthesis

Hoffmann, Christian ; Weigert, Joris ; Esche, Erik ; Repke, Jens-Uwe (2019-11-21)

A promising application of demand-side management is the chlor-alkali electrolysis. However, storing the produced chlorine for flexibility should be avoided whenever possible. If PVC is produced from chlorine, storing the intermediate 1,2-dichloroethane resulting from direct chlorination of ethene is a better alternative as it is less toxic than chlorine and can be easily stored. Currently, no ...

Sequential Flowsheet Optimization: Maximizing the Exergy Efficiency of a High-Pressure Water Scrubbing Process for Biogas Upgrade

Penteado, Alberto T. ; Schöneberger, Jan C. ; Esche, Erik ; Godini, Hamid Reza ; Wozny, Günter ; Repke, Jens-Uwe (2018-07-04)

Biogas is an important renewable energy source and potential raw material for the chemical industry. Its utilization frequently requires a treatment and/or upgrade step. The aim here is to maximize the exergy efficiency of a high-pressure water scrubbing process for upgrading biogas into biomethane by coupling a sequential modular simulation flowsheet with different optimization algorithms. By ...

Improving Convergence Behavior of Nonlinear Equation Systems in Intensified Process Models by Decomposition Methods

Bublitz, Saskia ; Esche, Erik ; Tolksdorf, Gregor ; Repke, Jens-Uwe (2018-07-04)

The two decomposition methods Dulmage-Mendelsohn (DM) decomposition and bordered block transformation (BBTF) have been examined on their capabilities to eliminate convergence problems during the iteration of large, nonlinear equation systems as they occur frequently in process modeling. They both divide the overall system into lower dimensional subsystems, which can be solved separately in sequ...

A Discrete-time Scheduling Model for Continuous Power-intensive Processes Considering Fatigue of Equipment

Obermeier, Andreas ; Windmeier, Christoph ; Esche, Erik ; Repke, Jens-Uwe (2018-07-04)

In the light of the growing renewable energy generation, matching of electricity supply and demand has become increasingly challenging. By participating in demand side management programs, industry can contribute to counter this challenge. However, the frequent adjustment of operation conditions according to volatile electricity prices leads to additional dynamic loads for the equipment. In thi...

The Systematic Design of CO2 Capture Processes Applied to the Oxidative Coupling of Methane

Penteado, Alberto ; Esche, Erik ; Salerno, Daniel ; Godini, Hamid Reza ; Repke, Jens-Uwe ; Wozny, Günter (2016-08-26)

The oxidative coupling of methane is the catalytic conversion of methane into ethene. Carbon dioxide is generated as a reaction by-product and must be removed from the gaseous stream. In this paper, the application of a hybrid carbon dioxide removal process including absorption with amines and gas separation membranes is investigated through simulations and cost estimations.