An original pyrolysis untt has been developed to study the influence of pyrolysis parameters: temperature, heating rate, wood particle size and moisture, gaseous environment, and catalyst impregnation. The effects of these parameters on char yield, dl and gas yield, and composttion are presented and interpreted to assist the industrial application of wood pyrolysis technology.Asphaltenk Bottom Cracking (ABC) is a catalytic hydrotreating process for heavy asphaitenic petroleum ends. ABC in combination with solvent deasphalting (SDA) is an effective way to completely convert and upgrade asphaltenic bottoms. This paper presents various correlations in SDA operations for yleids and properties of deasphaked oils (DAO) and asphalts obtained from KhafJi vacuum residua under different hydrotreating conditions. By using a mathematical model of the combined process of ABC and SDA, the quantitative reiatlonship between the recycle rate of SDA asphatt and the ABC conditlons in the extinction and partial recycle operations is discussed.

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Raman distributed temperature sensing (DTS) technologies are currently under evaluation by the nuclear and hydraulic industries as it may bring promising alternatives to classical measurement techniques. The reliability of the DTS measurements, as well as the traceability to the temperature standards, must be ensured throughout the entire period of monitoring (typically over a few tens of years). In order to achieve this goal, one key task consists in the verification of the performances claimed by the DTS devices manufacturers. Thus, the metrological performances and characteristics of the DTS devices, such as their limitations and accuracies, as well as the practical aspects of systems implemented on site should be evaluated step by step. This paper describes the dedicated facilities which have been developed at LNE in order to evaluate and to qualify DTS devices for very demanding applications. A first case study performed on one specific DTS device is detailed. A systematic bias has been observed among others on the spatial resolution. The DTS response to a temperature variation step over 1 m (spatial resolution typically claimed by the manufacturers) of sensing optical fibre corresponds indeed to only 90% of the temperature step magnitude, whereas the full DTS response is obtained in fact for 10 m (the practical spatial resolution) of sensing optical fibre solicited by this temperature step variation.

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The French National Metrology Institute LNE has improved its homemade laser flash apparatus in order to perform accurate and reliable measurements of thermal diffusivity of homogeneous solid materials at very high temperature. The inductive furnace and the associated infrared (IR) detection systems have been modified and a specific procedure for the in situ calibration of the used radiation thermometers has been developed. This new configuration of the LNE’s diffusivimeter has been then applied for measuring the thermal diffusivity of molybdenum up to 2200 °C, tungsten up to 2400 °C and isotropic graphite up to 3000 °C. Uncertainties associated with these high temperature thermal diffusivity measurements have been assessed for the first time according to the principles of the “Guide to the Expression of Uncertainty in Measurement” (GUM). Detailed uncertainty budgets are here presented in the case of the isotropic graphite for measurements performed at 1000 °C, 2000 °C and 3000 °C. The relative expanded uncertainty (coverage factor k = 2) of the thermal diffusivity measurement is estimated to be between 3 % and 5 % in the whole temperature range for the three investigated refractory materials.