Evaluating Toxicological Properties of Claydite Gravel, Containing Ferrovanadium Production Sludge, by Method of Biotesting with the of Higher Plants

Abstract

Recycling of sludge wastes, generated at industrial wastewater treatment and containing heavy metals, is a relevant and long-term task in building materials production. At that, the possibility of toxicants emission to the environment should be taken into account. This paper presents the findings of evaluating toxicological properties of artificial porous aggregates (claydite gravel), containing ferrovanadium production sludge, by means of using higher plants (Avena Sativa and Allium cepa) as test objects. It is demonstrated that adding sludge to the raw charge in amount up to 15% in the process of baking intensifies the melt formation with clay minerals, which contributes to the safe binding of heavy metals, reducing their diffusion to water media. Water extracts of the obtained claydite have no phytotoxic effect on higher plants.