One-dimensional model of solar thermal reactors for the co-production of hydrogen and carbon black from methane decomposition

Effect of seeding on hydrogen and carbon particle production in a 10 MW solar thermal reactor for methane decomposition

“…The simulation study has been performed using the onedimensional reactor e particle population model described in detail in [3]; the reader is referred to this work for an indepth understanding of the model and for validation results; however, an overview of the essential features and assumptions of the model is given below. The evolution of a polydisperse particle population along the reactor is modelled using a sectional method.…”

“…The evolution of a polydisperse particle population along the reactor is modelled using a sectional method. The single step decomposition of methane to hydrogen and carbon particles via a homogeneous and heterogeneous path is assumed and the kinetic parameters reported in [3] are used. Two particle populations are considered: 'fresh' particles, nucleated from homogeneous decomposition, and 'seed' particles, fed to the reactor.…”

“…Due to the small thermal mass and large surface area of the particles, energy conservation is considered only for the combined gas and particle phases (mixture). For further details regarding the model and its validation against experimental results, the reader is referred to [3].…”

“…The SOLHYCARB project involved, among others, the development of direct and indirect heating concept experimental solar reactors, the development of simulation tools (e.g. [3,4]) for the prediction of the hydrogen and carbon particle production rate in the developed solar reactors, as well as a study of the scale-up of the indirect heating concept reactor technology developed in the project to the 10 MW scale [5]. Two different reactor concepts are presently being developed in the field: directly heated reactors, in which the gasparticle flow is exposed directly to the concentrated solar radiation via a transparent window, e.g.…”

“…To this end, the authors have recently developed a one-dimensional reactor e particle population model for the design and control of indirectly heated solar reactors, which allows the size distribution of the product particles to be related quickly and simply to reactor process variables such as temperature, feed gas composition, flow rate and seed particle feed rate. The complete description of this model is given in [3], which includes an in-depth description of its differences and similarities with the models and simulations in the literature cited above, and validation of the model against a 10 kW indirectly heated unseeded solar reactor for which experimental results have been published in [14,22]. Furthermore, the same particle population model has also been applied recently within the framework of a two-dimensional CFD model [4] in order to study spatial non uniformities in particle formation and growth inside methane thermal decomposition reactors.…”