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In the present investigation, blends of two varieties of bamboo biomass with low-rank high-sulfur coal were prepared in different proportions. To assess their suitability as a fuel, pyrolysis and combustion experiments were carried out by using thermo-gravimetric analyzer (TGA), and various reactivity parameters were obtained from TGA data. Chemometric analysis, correlation, and principal component analyses (PCA) were used to correlate the physioco-chemical with fuel properties of blends. Most of the fuel properties of these blends depend upon the proportion of parent material in blends. Activation energies of blends during pyrolysis were found within the range as reported for other biomass and coal blends. However, activation energies of blends during combustion are lower than those reported for other biomass and coal blends. Chemometric analysis shows that blends with coal to bamboo ratio 50:50 are more suitable for pyrolysis and combustion purposes with lower sulfur emissions. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 315-321, 2014 [ABSTRACT FROM AUTHOR]

The micro-analysis of the inorganic constituents was performed on a tertiary Indian coal sample using computer-controlled scanning electron microscopy (CCSEM). A laboratory combustion experiment of the coal was also carried out to reveal the emission characteristics of particulate matters (PM2.5 and PM10). The results show the presence of major minerals like clay minerals, quartz, pyrite, and pyrrhotite forming the bulk of the mineral matter including some minor minerals, such as calcite, dolomite, ankerite, barite, oxidised pyrrhotite, and gypsum in the sample. The particle size distribution (PSD) of the included minerals is generally observed to be finer than that of the excluded ones in the coal. As a consequence, the coals rich in included minerals have smaller particles, which may affect its reactivity. The ratio of included to excluded minerals is found to be higher in majority of cases. It is found that Si mostly occurs as quartz and clay minerals, while Al mostly occurs as silicate minerals. Fe is primarily present as iron sulfides, iron oxide, and Fe-Al-silicate. S is partitioned into iron sulfides and gypsum. Most Ca occurs as carbonates and gypsum, with a minor fraction associated with clay minerals. Mg is mainly present as dolomite and clay minerals, with a very minor fraction present as ankerite. The majority of alkali elements are associated with aluminosilicates. P is mostly associated with kaolinite and/or present as more complex compounds containing Al, Si, and other elements as apatite is found to be absent in the coal studied. Ti is mainly present as rutile and kaolinite. The PSD of the individual elements were also determined in the coal by CCSEM data and 73.81 % of sulphur was found to be present as included indicating the high organically bound sulphur in the coal. During combustion, concentration of PM10 was found to be higher than PM2.5. The PMs are observed to contain of many potentially hazardous toxic elements viz. Si, Pb, S, Br, As, Cd, F and Cl. [ABSTRACT FROM AUTHOR]

Abstract: Two classes of amine fly ash based composites (FAA13 and FAA23) are prepared and evaluated as CO2 adsorbents. FAA13 is prepared from primary and tertiary amines (MEA/DMA) while FAA23 (DEA/DMA) is prepared from secondary and tertiary amines. Composites were characterized by elemental analyses such as Scanning electron microscope (SEM-EDX), UV–Visible, Fourier Transform Infra Red (FT-IR), carbon, hydrogen, nitrogen (CHN) and Thermo-gravimetric Analysis (TGA). A temperature-programmed degradation study shows a much higher stability in comparison with other known simple amine solvents. Carbamate-amine is formed by the reaction of fly ash–amine composite with CO2. Results showed the maximum adsorptions of CO2 of 6.89 and 5.99mmol/g on FAA13 and FAA23 respectively. Kinetics of CO2 on the composites was described by the linear driving force (LDF) model. The diffusion coefficients and activation energies of CO2 in the composites ranged between 6.33×10−12 ±7×10−12 cm2/s and 0.377±0.184kJ/mol respectively at atmospheric pressure and 306K. The prepared composites are thermally stable. A comparison of material cost and adsorption capacity showed that they are cheap and efficient for CO2 capturing. [Copyright &y& Elsevier]