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This study describes tar conversion on olivine in fluidized-bed gasification conditions. A laboratory-scale reactor (Aligator) was used to characterize phenol conversion to higher tars, before adding a sand and olivine bed to investigate heterogeneous steam reforming and the cokefaction of these tars. H2 and H2O atmospheres were tested both separately and together to characterize tar conversion on olivine. Catalytic activity in steam reforming was shown to be much improved by the presence of H2. In the absence of H2O in the reactive atmosphere, olivine caused a high cokefaction of tars. With 10% H2O and 20% H2, olivine became highly active in steam reforming of tars. Carbon deposition on the catalysts was quantified by temperature-programmed oxidation (TPO), and optical photographs of olivine were taken after tar conversion.

A simple screening protocol has been developed for assessing the agglomeration potential of active pharmaceutical ingredients (APIs) using resonant acoustic mixing that minimizes the quantity of API used. This methodology improves upon existing ones as it allows for multiple conditions to be screened in parallel, saving time and allowing for the study of agglomeration and optimization of the drying unit operation to take place early in development. In addition to a qualitative (visual) assessment, quantitative data can be obtained after the material has been dried therefore accounting for a measure of cake hardening. This methodology was also extended to assess the friability of the generated agglomerates and was validated using a scaled-down agitated filter dryer (AFD). The impact of particle size, particle size distribution, solvent selection, and solvent loading on the agglomeration potential for a Takeda API is also discussed which allowed for the development of an improved drying process that was successfully scaled-up in the pilot plant.

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The physics of the ITER edge and divertor plasma is strongly coupled with the divertor and the fuel cycle design. Owing to the limited space available the design as well as the remote maintenance approach for the ITER divertor are highly optimized to allow maximum space for the divertor plasma. Several auxiliary systems (e.g., in-vessel viewing instruments and glow discharge electrodes) as well as a part of the pumping and fuelling system have to be integrated together with the divertor into the lower level of ITER. Two main options exist for the choice of the plasma facing material in the divertor, i.e. tungsten and CFC. On the basis of already existing R&D results it is likely that the material choice will be mainly determined by physics considerations and material issues (e.g., C-T co-deposition). The requirements for the ITER fuel cycle arise from plasma physics as well as from the envisaged operation scenarios. Owing to the complex dynamic relationship of the fuel cycle subsystems among themselves and with the plasma, codes are employed for their optimization. These interacting issues are elaborated on the latest design status discussed.

Two-stage fixed bed gasification is one of the most promising technologies for low and medium energy production from biomass. In industrial processes, control and optimisation is often based on constructor know-how rather than on an understanding of the mechanisms involved. We present a new original tool, the Continuous Fixed Bed Reactor (CFiBR), which was specifically designed and built to enable a fine understanding of the limiting stage of a gasifier: the char bed gasification zone. The reactor, the instrumentation, the operating procedure and set-up tests are described in detail. The potential of the reactor is demonstrated through the characterisation of the gasification of a continuous wood char bed. Temperature profiles and gas concentrations along the 65 cm bed were established and showed that the most reactive zone was the first 10 cm of the char bed. Accurate energy and mass balances provided relevant information regarding the contributions of the main reactions involved in the fixed char bed gasification process. (Résumé d'auteur

In fixed bed gasifiers, the char bed gasification zone where char is converted into syngas plays a major role in terms of efficiency and control of the process. This zone is particularly complex as many phenomena compete, i.e. heterogeneous and homogeneous chemical reactions, gas flow in porous medium and flow of solid particles. This paper investigates the mechanical and thermochemical behavior of the char bed gasification zone and focuses particularly on bed compaction. To achieve this, a low-density biomass char from wood chips and a high-density one from wood pellets were gasified in a pilot scale continuous fixed bed reactor. Measurements of profiles were taken along the char bed for temperature, gas species concentration, char composition, char bed density and char particle velocity using fine instrumentation and specific char and gas sampling techniques. In our operating conditions, the char bed reactive zone is 3 times longer for chips (45 cm) than for pellets (16 cm). We show that pelletization has no effect on: char bed compaction, final char conversion (about 95%) and syngas quality (16% H2 and 13% CO). Finally, we discuss char bed compaction and the main phenomena that control it in order to propose a line of inquiry for modeling. (Résumé d'auteur