Dolomite-based binders manufactured using concentrated solar energy in a fluidised bed reactor

In this work, concentrated solar energy (CSE) was applied to an energy-intensive process such as the vitrification of waste with the aim of manufacturing glasses. Different types of waste were used as raw materials: a hazardous waste from the aluminum industry as aluminum source; two residues from the food industry (eggshell and mussel shell) and dolomite ore as calcium source; quartz sand was also employed as glass network former. The use of CSE allowed obtaining glasses in the SiO2-Al2O3-CaO system at exposure time as short as 15 min. The raw materials, their mixtures, and the resulting glasses were characterized by means of X-ray fluorescence, X-ray diffraction, and differential thermal analysis. The feasibility of combining a renewable energy, as solar energy and different waste for the manufacture of glasses, would highly contribute to circular economy and environmental sustainability.

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Behavior of a Heat-Protective Material Based on Al2O3 and SiO2 Fibers under Exposure to Concentrated Solar Energy Flux

Refractories and Industrial Ceramics ◽

10.1007/s11148-021-00541-4 ◽

2021 ◽

Author(s):

S. Kh. Suleimanov ◽

V. G. Babashov ◽

M. U. Dzhanklich ◽

V. G. Dyskin ◽

M. I. Daskovskii ◽

...

Keyword(s):

Solar Energy ◽

Energy Flux ◽

Protective Material ◽

Concentrated Solar Energy ◽

Solar Energy Flux

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Solid-State Redox Kinetics of CeO2 in Two-Step Solar CH4 Partial Oxidation and Thermochemical CO2 Conversion

Catalysts ◽

10.3390/catal11060723 ◽

2021 ◽

Vol 11 (6) ◽

pp. 723

Author(s):

Mahesh Muraleedharan Nair ◽

Stéphane Abanades

Keyword(s):

Solid State ◽

Solar Energy ◽

Kinetic Models ◽

Oxygen Carrier ◽

Co2 Conversion ◽

Oxidation Reactions ◽

Redox Kinetics ◽

Concentrated Solar Energy ◽

Ceria Reduction ◽

Kinetics Of

The CeO2/CeO2−δ redox system occupies a unique position as an oxygen carrier in chemical looping processes for producing solar fuels, using concentrated solar energy. The two-step thermochemical ceria-based cycle for the production of synthesis gas from methane and solar energy, followed by CO2 splitting, was considered in this work. This topic concerns one of the emerging and most promising processes for the recycling and valorization of anthropogenic greenhouse gas emissions. The development of redox-active catalysts with enhanced efficiency for solar thermochemical fuel production and CO2 conversion is a highly demanding and challenging topic. The determination of redox reaction kinetics is crucial for process design and optimization. In this study, the solid-state redox kinetics of CeO2 in the two-step process with CH4 as the reducing agent and CO2 as the oxidizing agent was investigated in an original prototype solar thermogravimetric reactor equipped with a parabolic dish solar concentrator. In particular, the ceria reduction and re-oxidation reactions were carried out under isothermal conditions. Several solid-state kinetic models based on reaction order, nucleation, shrinking core, and diffusion were utilized for deducing the reaction mechanisms. It was observed that both ceria reduction with CH4 and re-oxidation with CO2 were best represented by a 2D nucleation and nuclei growth model under the applied conditions. The kinetic models exhibiting the best agreement with the experimental reaction data were used to estimate the kinetic parameters. The values of apparent activation energies (~80 kJ·mol−1 for reduction and ~10 kJ·mol−1 for re-oxidation) and pre-exponential factors (~2–9 s−1 for reduction and ~123–253 s−1 for re-oxidation) were obtained from the Arrhenius plots.

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Comprehensive monitoring of a fluidised bed reactor for anaerobic treatment of high strength wastewater

Chemical Engineering Science ◽

10.1016/0009-2509(96)00160-1 ◽

1996 ◽

Vol 51 (11) ◽

pp. 2829-2834 ◽

Cited By ~ 5

Author(s):

P.A. Fitzgerald

Keyword(s):

High Strength ◽

Anaerobic Treatment ◽

Fluidised Bed ◽

Fluidised Bed Reactor

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Processing of intermetallic laminates by Self-Propagating High–Temperature Synthesis initiated with concentrated solar energy

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.161876 ◽

2022 ◽

Vol 891 ◽

pp. 161876

Author(s):

Ana Romero ◽

Gloria P. Rodríguez ◽

Enrique Marjaliza

Keyword(s):

High Temperature ◽

Solar Energy ◽

Temperature Synthesis ◽

Concentrated Solar Energy ◽

High Temperature Synthesis

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Techno-Economic Assessment of Solar-Driven Steam Gasification of Biomass for Large-Scale Hydrogen Production

Processes ◽

10.3390/pr9030462 ◽

2021 ◽

Vol 9 (3) ◽

pp. 462

Author(s):

Houssame Boujjat ◽

Sylvain Rodat ◽

Stéphane Abanades

Keyword(s):

Solar Energy ◽

Large Scale ◽

Biomass Gasification ◽

Sensitivity Study ◽

H2 Production ◽

Steam Gasification ◽

Economic Feasibility ◽

Production Costs ◽

Concentrated Solar Energy ◽

Land Cost

Solar biomass gasification is an attractive pathway to promote biomass valorization while chemically storing intermittent solar energy into solar fuels. The economic feasibility of a solar gasification process at a large scale for centralized H2 production was assessed, based on the discounted cash-flow rate of return method to calculate the minimum H2 production cost. H2 production costs from solar-only, hybrid and conventional autothermal biomass gasification were evaluated under various economic scenarios. Considering a biomass reference cost of 0.1 €/kg, and a land cost of 12.9 €/m2, H2 minimum price was estimated at 2.99 €/kgH2 and 2.48 €/kgH2 for the allothermal and hybrid processes, respectively, against 2.25 €/kgH2 in the conventional process. A sensitivity study showed that a 50% reduction in the heliostats and solar tower costs, combined with a lower land cost of below 0.5 €/m2, allowed reaching an area of competitiveness where the three processes meet. Furthermore, an increase in the biomass feedstock cost by a factor of 2 to 3 significantly undermined the profitability of the autothermal process, in favor of solar hybrid and solar-only gasification. A comparative study involving other solar and non-solar processes led to conclude on the profitability of fossil-based processes. However, reduced CO2 emissions from the solar process and the application of carbon credits are definitely in favor of solar gasification economics, which could become more competitive. The massive deployment of concentrated solar energy across the world in the coming years can significantly reduce the cost of the solar materials and components (heliostats), and thus further alleviate the financial cost of solar gasification.

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