In a previous paper, Brouwers and Van Eijk [1] presented a theoretical study on the dissolution (reaction) of pulverised powder coal fly ash. This fly ash was modelled as hollow spheres, and a shrinking core model was derived for these hollow spheres that contain two regions (an outer hull and an inner region). The obtained analytical equations were applied to the dissolution experiments by Pie...

Power generation from biomass is a substantial source of ashes, the extent of which depends on the type of biomass fuel and technology of combustion being used. The current study focuses on comparison of ashes with a special emphasis on hazardous organic compounds, particularly the polycyclic aromatic hydrocarbons (PAHs) fraction, present in ash. The reason is that ashes from combustion of wood...

The aim of this work is to evaluate the characteristics of activated and non-activated carbon obtained from carbon-enriched coal fly ashes (CECFA) from two different power stations to be used in the low temperature reduction of NO from stack gases. Carbon-rich fractions were obtained by mechanical sieving of fly ashes and by oil agglomeration. Activation of some samples was carried out in steam...

There is uncertainty as to the rates of coal fly ash needed for optimum physiological processes and growth. In the current study we tested the hypothesis that photosynthetic pigments concentrations and CO(2) assimilation (A) are more sensitive than dry weights in plants grown on media amended with coal fly ash. We applied the Terrestrial Plant Growth Test (Guideline 208) protocols of the Organi...

Geopolymers are inorganic polymers formed from the alkaline activation of amorphous alumino-silicate materials resulting in a three-dimensional polymeric network. As a class of materials, it is seen to have the potential of replacing ordinary Portland cement (OPC), which for more than a hundred years has been the binder of choice for structural and building applications. Geopolymers have emerge...

The synergistic effect of two fire retardants, a Si-Al compound and chlorinated paraffin, was tested on ultra-low density fiberboards (ULDFs). To further understand the mechanism of fire retardancy, morphologies of unburned and burned ULDFs were studied using a scanning electron microscope with energy dispersive spectroscopy. It was found that as the volume of the burned ULDFs shrank, some crev...

The Dutch cities Utrecht and Wijk bij Duurstede were founded by the Romans around 50 B.C. and the village Fijnaart and Graft-De Rijp around 1600 A.D. The soils of these villages are polluted with Pb (up to ~5000 mg/kg). Lead isotope ratios were used to trace the sources of Pb pollution in the urban soils. In ~75% of the urban soils the source of the Pb pollution was a mixture of glazed potsherd...

Marine sediments around urban areas serve as catch basins for anthropogenic particles containing polycyclic aromatic hydrocarbons (PAHs). Using incubations with gut fluids extracted from a deposit-feeding polychaete (Arenicola marina), we determined the digestive bioavailability of PAHs from fly ashes, coal dusts, diesel soots, tire tread materials, and urban particulates. We found that gut flu...