Publications related to Mass balance

Flowing Gas Experiments Reveal Mechanistic Details of Interfacial Reactions on a Molecular Level at Knudsen Flow Conditions

Christian Ludwig, Michel Rossi, Riccardo Iannarelli

Knudsen flow experiments and its interpretation in terms of adsorption/desorption kinetics as well as quantitative uptake on substrates of interest is presented together with the description of critical design parameters of the Knudsen Flow Reactor (KFR). ...

2022

Characterization of water sorption cycle in the cement microstructure of controlled oxide composition

Monisha Rastogi

This thesis investigates the water vapour sorption behaviour of samples with maximized calcium-silicate-hydrate (C-S-H) content. Primarily, the role of heterogeneous and homogeneous cavitation has been studied during the drying of cementitious materials. C ...

EPFL2022

The role of plasma-molecule interactions on power and particle balance during detachment on the TCV tokamak

Basil Duval, Christian Gabriel Theiler, Artur Perek, Kevin Henricus Annemarie Verhaegh, Mirko Wensing

This paper shows experimental results from the TCV tokamak that indicate plasma-molecule interactions involving D2+

IOP Publishing Ltd2021

Reactions of pyrrole, imidazole, and pyrazole with ozone: kinetics and mechanisms

Urs von Gunten, Peter Rudolf Tentscher, Sung Eun Lim

Five-membered nitrogen-containing heterocyclic compounds (azoles) belong to potential moieties in complex structures where transformations during ozonation can occur. This study focused on the azole-ozone chemistry of pyrrole, imidazole, and pyrazole as mo ...

ROYAL SOC CHEMISTRY2020

Revisiting the concept of extents for chemical reaction systems using an enthalpy balance

Dominique Bonvin, Diogo Filipe Mateus Rodrigues

For the investigation of complex reaction systems, it has been proposed to decouple the various rate processes using a linear time-invariant transformation that is constructed from knowledge of stoichiometry, reaction enthalpies, inlet compositions and tem ...

PERGAMON-ELSEVIER SCIENCE LTD2020

Reaction Degree of Metakaolin in Limestone Calcined Clay Cement (LC3)

Karen Scrivener, François Henri Avet

The amount of reacted metakaolin is determined using two methods: mass balance and thermodynamic modeling. It is found that mass balance is the most promising method. Thermodynamic modeling gives slightly underestimated results at late ages. ...

SPRINGER2018

Modifier adaptation with guaranteed feasibility in the presence of gradient uncertainty

Dominique Bonvin, Timm Faulwasser, Alejandro Gabriel Marchetti, Martand Singhal

In the context of real-time optimization, modifier-adaptation schemes use estimates of the plant gradients to achieve plant optimality despite plant-model mismatch. Plant feasibility is guaranteed upon convergence, but not at the successive operating point ...

Pergamon-Elsevier Science Ltd2017

Data Reconciliation for Reaction Systems Using Extents and Shape Constraints

Dominique Bonvin, Julien Léo Billeter, Sriniketh Srinivasan

Concentrations measured during the course of reactions are typically corrupted by random noise. Data reconciliation techniques improve the accuracy of measurements by using redundancies in the material and energy balances expressed as relationships between ...

Elsevier2017

Extent Computation under Rank-deficient Conditions

Dominique Bonvin, Julien Léo Billeter

The identification of kinetic models can be simplified via the computation of extents of reaction on the basis of invariants such as stoichiometric balances. With extents, one can identify the structure and the parameters of reaction rates individually, wh ...

2017

On Decoupling Chemical Reaction Systems : Methods, Analysis and Applications

Sriniketh Srinivasan

Chemical reaction systems act as the basis to get the desired products from raw materials. An in-depth understanding of all the underlying rate processes is necessary for monitoring, control and optimization of chemical reaction systems. Traditional repres ...

EPFL2017

Fast Estimation of Plant Steady State, with Application to Static RTO

Dominique Bonvin, Julien Léo Billeter, Michael Amrhein, Diogo Filipe Mateus Rodrigues

Experimental assessment or prediction of plant steady state is important for many applications in the area of modeling and operation of continuous processes. For example, the iterative implementation of static real-time optimization requires reaching stead ...

2016

Thermal-Hydraulic Analysis of the Low-T-c Superconductor (LTS) Winding Pack Design Concepts for the DEMO Toroidal Field (TF) Coil

Kamil Sedlák

Three design concepts, namely, WP#1, WP#2, and WP#3, for the low-T-c superconductor DEMO toroidal field coil was proposed in 2014. This paper is focused on the thermal-hydraulic analysis of all the designs using simplified models, which includes: 1) hydrau ...

IEEE Institute of Electrical and Electronics Engineers2016

Dynamics of wet flue gas desulphurization in spray absorber

A concise one dimensional thermal-hydraulic two-fluid model is presented for the numerical prediction of sulphur dioxide absorption from the flue gas onto drops of the water-limestone slurry in the vertical spray tower absorber. The model is based on mass, ...

2016

Use of Transient Measurements for the Optimization of Steady-State Performance via Modifier Adaptation

Dominique Bonvin, Grégory François

Real-time optimization (RTO) methods use measurements to offset the effect of uncertainty and drive the plant to optimality. RTO schemes differ in the way measurements are incorporated in the optimization framework. Explicit RTO schemes solve a static opti ...

American Chemical Society2014

Invariant Relationships for Heterogeneous Chemical Reaction Systems in Open Reactors

Dominique Bonvin, Julien Léo Billeter, Sriniketh Srinivasan

Many chemical and biochemical industries utilize chemical reaction processes to get desired products from raw materials. Common examples include reaction systems used to manufacture pharmaceutical drugs, vaccines and other chemicals. A chemical reaction sy ...

2014

FH HES Optimization of Chemical Reactor Feed by Simulations Based on a Kinetic Approach

Thierry Meyer, Francis Stoessel, Charles Ibrahim Guinand

Chemical incidents are typically caused by loss of control, resulting in runaway reactions or process deviations in different stages of the production. In the case of fed-batch reactors, the problem generally encountered is the accumulation of heat. This i ...

Schweizerische Chemische Gesellschaft2014

Variant and Invariant States for Reaction Systems

Dominique Bonvin, Julien Léo Billeter, Sriniketh Srinivasan

Models of chemical reactors can be quite complex as they include information regarding the reactions, the transfer of species between phases, the transfer of energy, and the inlet and outlet flows. Furthermore, the effects of the various phenomena are quit ...

2013

Use of Transient Measurements for Real-Time Optimization via Modifier Adaptation

Dominique Bonvin, Grégory François

Real-time optimization (RTO) methods use measurements to offset the effect of uncertainty and drive the plant to optimality. Explicit RTO schemes, which are characterized by solving a static optimization problem repeatedly, typically require multiple itera ...

2013

Towards kinetic modeling of genome-scale metabolic networks without sacrificing stoichiometric, thermodynamic and physiology constraints

Vassily Hatzimanikatis, Ljubisa Miskovic, Keng Cher Soh, Anirikh Chakrabarti

Mathematical modeling is an essential tool for a comprehensive understanding of cell metabolism and its interactions with the environmental and process conditions. Recent developments in the construction and analysis of stoichiometric models made it possib ...

2013

Incremental Model Identification of Fluid-Fluid Reaction Systems – Dynamic Accumulation and Reactions in the Diffusion Layer

Dominique Bonvin, Julien Léo Billeter, Sriniketh Srinivasan

The identification of kinetic models is an important step for the monitoring, control and optimization of industrial processes. This is particularly the case for highly competitive business sectors such as chemical and pharmaceutical industries, where the ...

2013