An SMC (Sheeting Moulding Compound) of Ðbre-glass and orthophthalic polyester has been pyrolysed in a 3É5 dm3 autoclave for 30 min in a nitrogen atmosphere at 300, 400, 500, 600 and 700¡C. Gas yields of 8È13 weight%, liquid yields of 9È16 weight% and solid residues of 72È82 weight% were obtained. The suitability of the pyrolysis process for recycling SMC is discussed. The characteristics, compositions and possible ways of reusing the liquid and gaseous fractions are presented. The solid pyrolysis residue has been recycled in another thermoset composite (Bulk Moulding Compound, BMC) and its mechanical properties have been compared with those of virgin BMC. The main conclusion is that pyrolysis can be an appropriate method for recycling thermoset polymeric composites such as SMC. The pyrolysis gas fraction can be sufficient to provide the energy requirements of the process plant. The pyrolysis liquids have high gross caloriÐc values (36É8 MJ kg~1) and are non-polluting liquid fuels ; about 40 weight% of such liquids could be used as petrols, and the remaining 60% could be mixed with fuel oils. The solid pyrolysis residue can be recycled in BMC with no detrimental e †ect on the BMC mechanical properties. Concerning temperature, it has been concluded that 400È500¡C are the most suitable temperatures for recycling SMC by pyrolysis.

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Aerosol size distributions from ferrous foundry cupola furnaces vary depending on semicontinuous process dynamics, time along the tap-to-tap cycle, dilution ratio, and the physical and chemical nature of the charge and fuel. All of these factors result in a highly time-dependent emission of particulate matter (PM) 2.5 m or less in aerodynamic diameter (PM 2.5 )-even on a mass concentration basis. Control measures are frequently taken on the basis of low-reliability parameters such as emission factors and loosely established mass ratios of PM 2.5 to PM 10 m or less in aerodynamic diameter (PM 10 ). The new environmental requirements could entail unexpected and undesired drawbacks and uncertainties in the meaning and effectiveness of process improvement measures. The development of process-integrated and flue-gas cleaning measures for reduction of particle emissions requires a better knowledge of generation mechanisms during melting. Available aerosol analyzers expand the range of control issues to be tackled and contribute to greatly reduce the uncertainty of engineering decisions on trace pollutant control. This approach combines real-time size distribution monitoring and cascade impactors as preseparators for chemical or morphological analysis. The results allow for establishing a design rationale and performance requirement for control devices. A number size distribution below 10 m in aerodynamic equivalent diameter was chosen as the main indicator of charge influence and filter performance. Size distribution is trimodal, with a coarse mode more than 12 m that contributes up to 30% of the total mass. A temporal series for these data leads to identification of the most relevant size ranges for a specific furnace (e.g., the most penetrating size range). In this cupola, this size range is between 0.32 and 0.77 m of aerodynamic equivalent diameter and defines the pollution control strategy for metals concentrating within this size range. Scrap quality effect is best monitored at less than 0.2 m in aerodynamic equivalent diameter and has been confirmed as strongly dependent on the physical state of the charge.

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