Leaching occurs in metals recovery, in contaminated soil washing, and in many natural processes, such as fertilizer dissolution and rock weathering. This paper presents a model developed to simulate the transient evolution of the dissolved chemical species in the heap and column isothermal leaching processes. In this model, the solid bed is numerically divided into plane layers; the recovery of...

Incineration is a widely used and well established technology for the municipal solid waste (MSW) management. Modern MSW incineration plants are equipped with improved air pollution control (APC) systems, which reduce pollutants well below the established limits. The environmental concern has, thus, moved from the air emissions to the solid residues generated from the APC systems of the inciner...

Military small arms shooting range (SASR) soils are heavily polluted by metals like copper, lead, antimony, and zinc. This study was carried out to define efficient operating conditions to solubilize these metals by a chemical leaching technique. The comparison of different leaching reagents (HCl, H2SO4, CH3COOH, and EDTA) has revealed that sulfuric acid leaching coupled with the addition of so...

Heap leaching is a well-established metallurgical technology which allows metal recovery (e.g., Au, Cu, U) from low-grade ores. However, spent heap leach materials remaining at abandoned or historic mine sites may represent a potential source of contamination. At the Croydon Au-mines, heap leaching operations (1984–1985) were performed on mineralized rhyolites hosting sulphides including pyrite...

The effect of metabolites from the indigenous Acidithiobacillus thiooxidans and temperature on the bioleaching of cadmium from soil was investigated in the present study. Bioleaching was found to be more effective than chemical leaching of cadmium. The metabolite, mainly sulfuric acid, which was shown to be growth-associated in the exponential phase, plays a major role in bioleaching. The maxim...

Land application is a cost-effective way of disposing of wood ash. However, high volume wood ash application tends to increase soil pH, solubilizing soil organic matter (SOM), and enhancing metal mobility. Column studies (1.5 20 cm) were conducted to determine the leachability of Cu and Ni in an ash-amended soil. In the first study, deionized water was used to leach three columns: ash, ash mixe...