Publications related to Pebble-bed reactor

Intra-pin Reaction Rate Measurements in the CROCUS Experimental Reactor

Andreas Pautz, Vincent Pierre Lamirand, Mathieu Hursin, Oskari Ville Pakari, Thomas Jean-François Ligonnet, Tom Mager

In response to the need for validating high-fidelity deterministic neutronics solvers capable of providing pin-resolved neutron flux distributions, intra-pin reaction rates measurements were performed in the CROCUS experimental reactor. A specially designe ...

2024

Gamma noise to non-invasively monitor nuclear research reactors

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari, Pavel Frajtag, Tom Mager

Autonomous nuclear reactor monitoring is a key aspect of the International Atomic Energy Agency’s strategy to ensure nonproliferation treaty compliance. From the rise of small modular reactor technology, decentralized nuclear reactor fleets may strain the ...

Nature Research2024

Neutron-Gamma Noise Measurements in a Zero-Power Reactor Using Organic Scintillators

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari

Noise measurements in light water reactor systems aid in generating validation data for integral point kinetic parameter predictions and generating monitoring parameters for reactor safety and safeguards. The CROCUS zero-power reactor has been used to supp ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Design of an Instrumented Fuel Rod for Intra-pin Neutron Flux Measurements in the CROCUS Experimental Reactor

Andreas Pautz, Vincent Pierre Lamirand, Mathieu Hursin, Thomas Jean-François Ligonnet, Won Dong Shin, Tom Mager

In response to the need for validating high-fidelity deterministic neutronics solvers capable of pin-resolved neutron flux distributions, an instrumented fuel rod was designed for the experimental reactor CROCUS, operated by EPFL’s Laboratory for Reactor P ...

2023

A holistic investigation of photocatalytic hydrogen generation

Sangram Ashok Savant

Photocatalytic (PC) solar hydrogen production is a promising way to provide green hydrogen using only sunlight and abundant reactants such as water. PC approaches use catalytically active semiconductor particles suspended in liquid electrolytes. The partic ...

EPFL2023

Design and operational guidelines of solar-driven catalytic conversion of CO2 and H2 to fuels

Sophia Haussener, Sha Li

Sunlight-powered catalytic conversion of CO2 and (green) H2 into fuels and chemicals via Sabatier and reverse water gas shift (RWGS) processes offers a promising solution to reduce greenhouse gas emissions and increase renewable energy utilization. The suc ...

ELSEVIER SCI LTD2023

On the development of multi-physics tools for nuclear reactor analysis based on OpenFOAM (R): state of the art, lessons learned and perspectives

Carlo Fiorina

In the last two decades, the use of OpenFOAM as a multi-physics library for nuclear applications has grown from a sporadic use for exploratory studies to a widespread application for the analysis of innovative reactor concepts and highly complex problems. ...

ELSEVIER SCIENCE SA2022

Quantitative Design of a New e-Methanol Production Process

Alfred Rufer

In the context of the need to significantly reduce greenhouse gas emissions from personal transportation, a new process for the production of e-methanol is presented. It is a CO2 hydrogenation process, powered mainly by renewable energy sources such as pho ...

MDPI2022

Thermodynamic modelling of hydrogen production in sorbent-enhanced biochar-direct chemical looping process

Hydrogen (H-2) has been widely considered the clean energy carrier of choice for emerging renewable energy generation technologies. However, H-2 is a secondary fuel mainly derived from natural gas. Over the past decades, research on developing H-2 producti ...

2022

Advanced methodologies for modeling and assessment of SFR safety functions

Janos Bodi

The present doctoral work was performed to contribute to the conceptual design development and safety assessment of a Generation IV Sodium Fast Reactor (SFR) in the frame of the European Sodium Fast Reactor Safety Measures Assessment and Research Tools (ES ...

EPFL2022

Construction of Fe3O4 bridged Pt/g-C3N4 heterostructure with enhanced solar to fuel conversion

Michael Graetzel, Shaik Mohammed Zakeeruddin

In this study, we report the effects of co-catalysts of Pt nanoparticles and Fe3O4 clusters on photocatalytic behaviors of g-C3N4 (CN) and the use of the resulting photocatalyst for CO2 photoreduction to solar fuels in a flow reactor operated at room-tempe ...

ELSEVIER2022

Flexibilisation of Biogas-Based Power-to-Gas Processes: A Techno-Economic and Experimental Assessment

Andreas Gantenbein

Biogas-based power-to-X technology allows storing renewable electricity, while producing CO2-neutral products. This work investigates the conversion and upgrading of digestion-derived gas mixtures with focus on increasing the operational flexibility of the ...

EPFL2022

A Hybrid Approach to Neutron Transport with Thermal-hydraulic Feedback for Reactor Transient Analysis

Alexander Aures

Understanding the time-dependent behaviour of a nuclear reactor following an intended or unintended change of the reactor conditions is of crucial importance to the safe operation of nuclear reactors. Safety evaluations of nuclear reactors involve the anal ...

EPFL2021

Techno-economic analysis and life cycle assessment of a biorefinery utilizing reductive catalytic fractionation

Jeremy Luterbacher

Reductive catalytic fractionation (RCF) is a promising approach to fractionate lignocellulose and convert lignin to a narrow product slate. To guide research towards commercialization, cost and sustainability must be considered. Here we report a techno-eco ...

2021

Optimisation of used nuclear fuel canister loading using a neural network and genetic algorithm

Andreas Pautz, Hakim Ferroukhi, Dimitri Rochman, Alexander Vasiliev

This paper presents an approach for the optimisation of geological disposal canister loadings, combining high resolution simulations of used nuclear fuel characteristics with an articial neural network and a genetic algorithm. The used nuclear fuels (produ ...

SPRINGER LONDON LTD2021

Real-time feedback control of the impurity emission front in tokamak divertor plasmas

Basil Duval, Christian Gabriel Theiler, Federico Alberto Alfredo Felici, Cristian Galperti, Artur Perek

In magnetic confinement thermonuclear fusion the exhaust of heat and particles from the core remains a major challenge. Heat and particles leaving the core are transported via open magnetic field lines to a region of the reactor wall, called the divertor. ...

Nature Research2021

Drift-related transport and plasma-neutral interaction in the TCV divertor

Mirko Wensing

Thermonuclear fusion of light atoms is the primary energy source of stars, such as our Sun, that led to the emergence of life on Earth. However, its economic exploitation as a virtually unlimited and clean energy source is yet to be developed. One of the m ...

EPFL2021

Constraining the response factors of an extractive electrospray ionization mass spectrometer for near-molecular aerosol speciation

Julia Schmale, Imad El Haddad, Yandong Tong

Online characterization of aerosol composition at the near-molecular level is key to understanding chemical reaction mechanisms, kinetics, and sources under various atmospheric conditions. The recently developed extractive electrospray ionization time-of-f ...

2021

Statistical Burnup Distribution of Moving Pebbles in the High-Temperature Reactor HTR-PM

Andreas Pautz, Jiri Krepel, Fanny Vitullo, Horst-Michael Prasser

In the pebble-bed high-temperature reactor under construction in China, called the HTR-PM, the spherical fuel elements continuously flow downward in the cylindrical core. The burnup of each pebble is checked at the core outlet and, according to the achieve ...

ASME2020

Analysis of the sorption-enhanced chemical looping biomass gasification process: Performance assessment and optimization through design of experiment approach

François Maréchal, Thanaphorn Detchusananard

In this study, the performance of high-purity hydrogen production through the sorption-enhanced chemical looping gasification (SECLG) process, involving a gasifier, calciner, and air reactor, was investigated. In this process, the biomass feedstock was woo ...

2020