The third life of CSP: solar high temperature processes,

International audienc

Solar thermochemical gasification of wood biomass for syngas production in a high-temperature continuously-fed tubular reactor

International audienceHydrogen Biomass Pyrolysis Gasification Solar reactor a b s t r a c t Biomass gasification is an attractive process to produce high-value syngas. Utilization of concentrated solar energy as the heat source for driving reactions increases the energy conversion efficiency, saves biomass resource, and eliminates the needs for gas cleaning and separation. A high-temperature tubular solar reactor combining drop tube and packed bed concepts was used for continuous solar-driven gasification of biomass. This 1 kW reactor was experimentally tested with biomass feeding under real solar irradiation conditions at the focus of a 2 m-diameter parabolic solar concentrator. Experiments were conducted at temperatures ranging from 1000 C to 1400 C using wood composed of a mix of pine and spruce (bark included) as biomass feedstock. This biomass was used under its non-altered pristine form but also dried or torrefied. The aim of this study was to demonstrate the feasibility of syngas production in this reactor concept and to prove the reliability of continuous biomass gasification processing using solar energy. The study first consisted of a parametric study of the gasification conditions to obtain an optimal gas yield. The influence of temperature, oxidizing agent (H 2 O or CO 2) or type of biomass feedstock on the product gas composition was investigated. The study then focused on solar gasification during continuous biomass particle injection for demonstrating the feasibility of a continuous process. Regarding the energy conversion efficiency of the lab scale reactor, energy upgrade factor of 1.21 and solar-to-fuel thermochemical efficiency up to 28% were achieved using wood heated up to 1400 C

Unique Fresnel demonstrator including ORC and thermocline direct thermal storage: operating experience

International audienc

Unique Fresnel demonstrator including ORC and thermocline direct thermal storage: operating experience

International audienc

A high temperature drop-tube and packed-bed solar reactor for continuous biomass gasification

International audienc

Membrane fractionation of biomass fast pyrolysis oil and impact of its presence on a petroleum gas oil hydrotreatment.

International audienceIn order to limit the greenhouse effect causing climate change and reduce the needs of the transport sector for petroleum oils, transformation of lignocellulosic biomass is a promising alternative route to produce automotive fuels, chemical intermediates and energy. Gasification and liquefaction of biomass resources are the two main routes that are under investigation to convert biomass into biofuels. In the case of the liquefaction, due to the unstability of the liquefied products, one solution can be to perform a specific hydrotreatment of fast pyrolysis bio-oils with petroleum cuts in existing petroleum refinery system. With this objective, previous studies [Pinheiro et al., 2009], [Pinheiro et al., 2011] have been carried out to investigate the impact of oxygenated model compounds on a straight run gas oil (SRGO) hydrotreatment using a CoMo catalyst. The authors have demonstrated that the main inhibiting effects are induced from CO and CO2 produced during hydrodeoxygenation of esters and carboxylic acids. To go further, cotreatment of a fast pyrolysis oil with the same SRGO as used in the previous studies was investigated in this present work. Firstly the bio-oil was separated into four fractions by membrane fractionation using 400 and 220 Da molecular weight cut-off membranes. The bio-oil and its fractions were analyzed by spectroscopic and chromatographic techniques. Then, one fraction (i.e. fraction enriched in compounds with molecular weight from 220 to 400 Da) was mixed with the SRGO and co-treated. Despite some experimental difficulties mainly due to the emulsion instability, the hydrotreatment was successful. An inhibition has been observed on the HDS, HDN and HDCa reactions of the SRGO in presence of the bio-oil fraction. The measurement of the CO/CO2/CH4 molar flowrate at the reactor outlet showed that the inhibition was due to the presence of CO and CO2 coming from HDO rather than to the oxygen compounds themselves

Solar Biomass Gasification in Presence of Metal Oxide

International audienc

Solar Biomass Gasification in presence of iron oxide

International audienc

Hydrogen production from solar-driven biomass gasification in a high-temperature continuously-fed solar reactor

International audienc

Dynamic simulations of Fresnel solar power plants

International audienceAs solar energy is a variable power source, solar power plants are facing transients that are not experienced in conventional power plants such as nuclear or fossil ones. It is thus of primary importance to be able to simulate the dynamic behavior of the solar plants for their design and operation. The regulation modes have to be decided and the operation strategy has to be optimized. Using concentrated solar energy enables to convert solar power into heat before running thermodynamic cycles. Thermal inertia of the systems along with possible heat thermal storages help to smooth solar variations provided that these systems can be managed dynamically. Two solar power plants (with oil or water/steam as heat transfer fluid) are simulated with Dymola using Modelica code. The solar power plant using oil as heat transfer fluid is already running and preliminary results are compared with simulated data. Concerning the solar steam power plant, the model is run to investigate the regulation scheme of the plant that will be commissioned at the end of 2013. For both plant a DNI perturbation is tested and results are discussed concerning the system response and possible improvement