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This paper describes fire safety experiments on Australian native timber samples with a special focus on their use in bushfire-prone areas. Nine species were assessed through testing in a cone calorimeter, thermogravimetric analysis and differential scanning calorimetry (DSC). The effects of density, moisture content and chemical extractives content were evaluated. Marked differences in ignition times were found, possibly due to variations in density across species, as well as the chemical extractives content. Analysis of the heat flow through DSC indicated that the type of extractives can influence the fire safety performance and that this aspect of wood properties merits further study. One additional species was identified as a suitable candidate for bushfire-resisting species in the Australian bushfire context. • Determination of flammability of northern Australia timber species. • Multiscale testing of varied density and extractive content. • Assessment for timber use in bushfire attack level 29 zones. • Extractives content and ignition have linear correlation. [ABSTRACT FROM AUTHOR]

In this manuscript, we report the analysis of eight uranium ore concentrates (UOCs) from three operating Australian uranium mines using thermogravimetric analysis to investigate whether the thermal decomposition of these UOCs can be used to differentiate between sources. Micro-Raman spectroscopy and X-ray diffraction were also used to identify the different phases present within the original UOC material, as well as chart their decomposition with the increasing temperature. UOCs of different species were able to be differentiated from one another, while the moisture content, a variable component within the UOCs, did distinguish between UO samples sourced from Ranger and Olympic Dam. The effect of elevated temperatures on the diverse UOC morphologies of the three UOCs was also examined. [ABSTRACT FROM AUTHOR]

Abstract: This study is part of a program assessing the suitability of chemical looping for direct combustion of Victorian brown coal. The performance of NiO as an oxygen carrier in presence of a dried Victorian brown coal was assessed during five alternating cycles of reduction and oxidation in a CO2 environment using a TGA. The experiments indicate a 4.4–7.5% weight loss of the oxygen carrier per cycle. Preliminary SEM-EDX and FACTSAGE predictions also indicate weight loss, but not to the same extent. The percentage of combustion of coal achieved at the 5th cycle was approximately 67%. Cycle 2 showed maximum reactivity (during reduction) with a decreasing trend during the subsequent cycles. These initial experiments did not reveal much agglomeration between ash and NiO although longer duration experiments are required to explore this issue further. [Copyright &y& Elsevier]

Abstract: Transformation of pyrite in an Australian lignite during pyrolysis was studied using a thermogravimetric analyser (TGA) and a fixed-bed reactor. Samples of a lignite with high pyrite content, a pyrite-free lignite, acid-washed lignite, a pyrite mineral, and pyrite-free lignite blended with various amounts of the pyrite minerals were employed in the experimentation. It was shown that in nitrogen the pyrite mineral (S/Fe=2) decomposes to troilite (S/Fe=1) at ca. 1200K and above this temperature, some of the troilite further decomposes to form elemental iron (S/Fe<1). However, when blended with the demineralised lignite, the pyrite mineral can be completely decomposed to troilite at 873K as confirmed by FTIR, SEM-EDS and XRD analyses on the resulting chars. During the TGA pyrolysis of the pyrite–lignite blends, two DTG peaks were observed, indicating two major decomposition events occurring. The first DTG peak was related to the devolatilisation of the lignite, while the second peak was attributed to the pyrite decomposition. Using a mass spectroscopy coupled with the TGA, it was revealed that hydrogen sulphide and a small quantity of sulphur dioxide were released during the pyrolysis of the pyrite–lignite blends. However, only sulphur dioxide was detected during the pyrolysis of the lignite with high pyrite content. This is attributed to the reactions of the inherent pyrite with oxygenates in the lignite structure. By analysing sulphur retention in the chars, it was shown that inherent inorganic matter in the raw lignite retains part of the sulphur in the solid phase. For the pyrite–lignite blends, pyrite initially decomposes to form FeS, some of which further decomposes to elemental iron at a much slower rate. [Copyright &y& Elsevier]

The high-temperature thermal destruction of poultry derived wastes (e.g., manure and bedding) for energy recovery is viable in Australia when considering resource availability and equivalent commercial-scale experience in the UK. In this work, we identified and examined the opportunities and risks associated with common thermal destruction techniques, including: volume of waste, costs, technological risks and environmental impacts. Typical poultry waste streams were characterised based on compositional analysis, thermodynamic equilibrium modelling and non-isothermal thermogravimetric analysis coupled with mass spectrometry (TG–MS). Poultry waste is highly variable but otherwise comparable with other biomass fuels. The major technical and operating challenges are associated with this variability in terms of: moisture content, presence of inorganic species and type of litter. This variability is subject to a range of parameters including: type and age of bird, and geographical and seasonal inconsistencies. There are environmental and health considerations associated with combustion and gasification due to the formation of: NO X , SO X , H2S and HCl gas. Mitigation of these emissions is achievable through correct plant design and operation, however, with significant economic penalty. Based on our analysis and literature data, we present cost estimates for generic poultry-waste-fired power plants with throughputs of 2 and 8 tonnes/h. [Copyright &y& Elsevier]

In order to investigate the potential of thermal analysis for the determination of post-mortem age, rib bone specimens were collected from the remains of a number of slaughtered pigs that were allowed to decompose in the Australian bush in a controlled site under a range of conditions for time periods ranging from 1 to 5 years. The bone specimens were cut in cross-section with the compact bone collected for analysis. TG-MS curves were collected by heating bone samples to 1100°C in an argon atmosphere. The TG-MS data showed significant differences for the pig bone specimens derived from the different environments and showed trends in peak size correlating with age. The reported data suggest that TG-MS has significant potential for the identification of origin as well as the ageing of skeletal remains in a forensic context. [ABSTRACT FROM AUTHOR]

Investigations into the pyrolytic behaviour during co-pyrolysis of coal, biomass materials and coal/biomass blends prepared at different ratios (10:90, 20:80, 30:70 and 50:50) have been conducted using a thermogravimetric analysis (TGA) apparatus. The coal sample selected was Collie sub-bituminous coal from Western Australia, while wood waste (WW) and wheat straw (WS) were used as biomass samples. Three thermal events were identified during the pyrolysis. The first two were dominated by the biomass pyrolysis, while the third was linked to the coal pyrolysis, which occurred at much higher temperatures. No interactions were seen between the coal and biomass during co-pyrolysis. The pyrolytic characteristics of the blends followed those of the parent fuels in an additive manner. Among the tested blends, 20:80 blends showed the lowest activation energies of 90.9 and 78.7 kJmol(-1) for coal/WW and coal/WS blends respectively. The optimum blend ratio for pyrolysis of coal/WS was 50:50 with a high degradation rate in all the thermal events and a higher mass loss over the course of the co-pyrolysis compared to coal/WW blends examined. The reaction orders in these experiments were in the range of 0.21-1.60, thus having a significant effect on the overall reaction rate. Besides the pyrolysis of coal alone, the 50:50 coal/biomass blends had the highest reaction rate, ranging 1x10(9)-2x10(9) min(-1). The experimental results may provide useful data for power generation industries for the development of co-firing options with biomass.