Chromium (VI) Galvanic Bath: Chemical Treatments and Possible Recycling Ways of the Obtained Sludges

Galvanic processes, that increase corrosion resistance properties and improve wear qualities of metal materials, are based on metal plating baths and rinsewaters. They generate effluents with a metal concentration varying with the installed process. Traditional systems reduce the toxicity of wastewater by aggregating disposed aqueous solutions of various concentrations, followed by treatment with chemicals to coagulate, flocculate, and settle out solid wastes for off-site disposal. In this paper the efficiency of different precipitating agents was evaluated in order to obtain a Cr (III) sludge.There are several treatment routes proposed in the literature to avoid dumping, or in other words, recycle the wastes. Recent increase in the cost of landfill disposal and decrease in number of disposal sites have led to consideration of alternative routes and treatments. For this reason, the screening results of scientific activity conducted on a laboratory scale on the possibility to both inertize and valorize the obtained galvanic sludge in the traditional ceramic filed (glasses, bricks, tiles, pigments and glazes) were reported with particular emphasis on the possible problems and the possible ways to solve them.