Fly Ash

Soil contamination by potentially toxic elements (PTEs) has led to adverse environmental impacts. In this review, we discussed remediation of PTEs contaminated soils through immobilization techniques using different soil amendments with respect to type of element, soil, and amendment, immobilization efficiency, underlying mechanisms, and field applicability. Soil amendments such as manure, compost, biochar, clay minerals, phosphate compounds, coal fly ash, and liming materials are widely used as immobilizing agents for PTEs.
The versatile use of droplet coagulation to recycle complex waste resources (fly ash FA, rice husk ash RHA and alum sludge AS) was investigated. Monodisperse microspheres were shaped, creating higher impact on the applicability of the waste resources. In order to obtain a suspension with appropriate rheological properties, pre-processing was required for the AS powder in contrast to the RHA and FA powders. Furthermore, the impact of the shaping process and waste stream properties on the calcination and sintering was determined and correlated to the microstructure of the sintered spheres.