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Experimental tests were carried out with an adapted bench-scale mass loss calorimeter (MLC) and also in an outdoor wind tunnel to estimate the heat release rate (HRR) of a forest fuel bed. The MLC apparatus uses a calibrated thermopile to quantify the HRR, as an alternative to the classical measurement of oxygen consumption due to combustion. Additional calibration of thermocouples to measure gas temperatures enabled estimation of HRR in experimental burnings conducted in the wind tunnel. The results showed a reasonable agreement between peak HRR (PHRR) values obtained in the MLC and in the wind tunnel, and also demonstrated that PHRR was significantly affected by the wind speed and the rate of spread. The proposed procedure is potentially useful as an initial step in monitoring HRR in outdoor forest fire experiments.

An adapted bench-scale Mass Loss Calorimeter (MLC) device for evaluating forest fuel flammability and combustion properties is proposed. This fire test apparatus consists of an MLC fitted with a chimney containing a thermopile. After the thermopile output has been calibrated by use of a methane burner, these data are used to quantify heat release, as an alternative to the classical measurement of oxygen consumption due to combustion. The results showed good repeatability and reasonable approximation to HRR values obtained with a cone calorimeter, and also demonstrated that each variable analyzed was significantly affected by the species considered.

The retention of mercury vapor by sulfur supported on sepiolite has been studied, and the utility of sepiolite as a dispersant for the active phase, sulfur, has been thoroughly ascertained. Samples with 10% S supported on sepiolite of varying size and shape have been prepared from powders sulfurized by reaction/deposit, and their efficiency in depurating air streams with 95 ppm mercury has been tested in a dynamic system using a fixed-bed glass reactor and fluid velocities ranging from 3.1 to 18.9 cm s^-1. From breakthrough curves under various sets of conditions, the importance of mass transfer under the process conditions has been proven. The progress of the reaction is limited by the resistance to reactant diffusion inside the solid through the layer of product formed. Sulfur reaction to HgS is reduced to an external zone of the solid, giving rise to an egg-shell deposit whose extension is related to sulfur dispersion and porosity of the adsorbent. Then, conversion and capacity of the samples are related to their porosity and S/V ratio. The use of SEM helps to confirm those statements. The 10% S samples compare well with the more conventional S/activated carbon, with their use being advantageous for the low price and abundance of the substrate.

Three samples of naturally occurring sepiolite from different deposits in Spain were used as catalysts for the Claus reaction 2nH2S+ nSO2→3n/xSx+ 2nH2O (ΔH = −109.2kJ mol−1) at low temperatures (< 400 K), to purify sulphur compounds (H2S and SO2) from tail-gas. The process was carried out in a fluidized bed reactor of the semicontinuous type on a semi-pilot scale. The sulphur produced in the reaction condenses on the solid surface contributing to its deactivation by fouling. Sulphur incorporation into the solid is governed by internal diffusion of the reactants in microdomains of the porous network, the factors affecting the latter being of capital importance in the occupation degree of the solid. The textural characteristics of the catalysts supports were studied by porosimetric techniques: nitrogen adsorption-desorption isotherms and mercury intrusion. Two pore-plugging mechanisms, the wedge layered (WLM) and the complete layered (MMM) mechanisms are described and applied to the porosimetric data of the sulphurized samples in order to ascertain the number of layers penetrating the system. Significant differences in the pore filling were observed by the application of the models which were related to factors affecting reactant diffusivity within the porous network: texture of the involved solids, working temperature (373–473 K) and reactant concentration (2–4% v/v H2S). Significant conclusions regarding the possibilities of sulphur recovery, in relation to the texture of the solids involved, may be reached in this study, but also, and more general, regarding parameters affecting catalyst deactivation by fouling.

A general mechanism is widely accepted to explain the photostability of an important class of UV absorbers (or light screeners) which have a phenolic group intramolecularly bonded to a heteroatom.