Hazardous waste stabilization with clean-coal technology ash residuals

Abstract

Clean coal technology by-products, collected from commercial operations under steady state conditions, are reacted at bench-scale with metal-laden hazardous wastes. Reaction conditions involve mixing calibrated weight ratios of by-product to hazardous waste with attention to minimizing added moisture. Of the 15 heavy metals monitored, lead appeared to be the element of greatest concern both from a leaching and a regulatory point of view. While leaching information is focused on lead stabilization, similar information exists for other metals as well. Stabilized solid products of reactions are sampled for TCLP evaluations. For samples showing evidence of metal stabilization, further experimentation was conducted evaluating optimum moisture content and development of physical strength (measured as compressive strength) over time of curing. Results show that certain hazardous wastes are highly amenable to chemical stabilization, while others are not; certain by-products provided superior stabilization, but did not allow for strength generation over time.

Electrostatic painting residues as an alternative raw material for red clay industry

“…Several authors have shown that solidification, stabilization, and vitrification processes can be used to recycle different residues such as: radioactive residues (Garrido et al 2004); ash from incineration processes (Romero et al 1999, Kim et al 2000, Cheeseman et al 2003, galvanizing residues (Silva & Mello Castanho 2004); iron-rich resi-dues from hydrometallurgical processes, used to obtain various types of glass and ceramic glass (Pelino 2000); coal ash (Neufeld et al 1996, Cimdins et al 2000, Pereira et al 2001; fly ash (Parsa et al 1996, Barbieri et al 2000, Pisciella et al 2000, Jonker & Potgieter 2005; residues from steel-making processes, which contain Zn, Pb, Cd, Ni, and Cr, that have been mixed with clays to obtain the so-called 'ecological bricks ' (Dominguez et al 1996). Several authors have shown that solidification, stabilization, and vitrification processes can be used to recycle different residues such as: radioactive residues (Garrido et al 2004); ash from incineration processes (Romero et al 1999, Kim et al 2000, Cheeseman et al 2003, galvanizing residues (Silva & Mello Castanho 2004); iron-rich resi-dues from hydrometallurgical processes, used to obtain various types of glass and ceramic glass (Pelino 2000); coal ash (Neufeld et al 1996, Cimdins et al 2000, Pereira et al 2001; fly ash (Parsa et al 1996, Barbieri et al 2000, Pisciella et al 2000, Jonker & Potgieter 2005; residues from steel-making processes, which contain Zn, Pb, Cd, Ni, and Cr, that have been mixed with clays to obtain the so-called 'ecological bricks ' (Dominguez et al 1996).…”

“…The aim of this process is to immobilize hazardous substances that are present in residues (Neufeld et al 1996). The aim of this process is to immobilize hazardous substances that are present in residues (Neufeld et al 1996).…”

“…The use of the stabilization/solidification process as an option for the treatment of a variety of solid residues is continuously growing. The aim of this process is to immobilize hazardous substances that are present in residues (Neufeld et al 1996).…”

“…Due to the characteristics of the electrostatic painting residue, the solidification/stabilization process appears to be an alternative to its treatment. Several authors have shown that solidification, stabilization, and vitrification processes can be used to recycle different residues such as: radioactive residues (Garrido et al 2004); ash from incineration processes (Romero et al 1999, Kim et al 2000, Cheeseman et al 2003, galvanizing residues (Silva & Mello Castanho 2004); iron-rich resi-dues from hydrometallurgical processes, used to obtain various types of glass and ceramic glass (Pelino 2000); coal ash (Neufeld et al 1996, Cimdins et al 2000, Pereira et al 2001; fly ash (Parsa et al 1996, Barbieri et al 2000, Pisciella et al 2000, Jonker & Potgieter 2005; residues from steel-making processes, which contain Zn, Pb, Cd, Ni, and Cr, that have been mixed with clays to obtain the so-called 'ecological bricks ' (Dominguez et al 1996). The present study was therefore based on this solid residues treatment technology.…”