Determinação da sorção de chorume em xisto retortado

Abstract

The main purpose of this work is evaluate the adsorptive capacity of contaminants in the leachate through adsorption by pyrolysed oil shale, residue from oil shale retorting process with considerable adsorption capacity of some components, being a proposal for the allocation and removal of the components present in leachate, using layers of this residue in the construction of embankments to prevent the passage of contaminants to soil and groundwater. For checking the efficiency of the adsorption of these leachate contaminating compounds, adsorption columns were built with different doses of pyrolysed oil shale, 30, 80 and 130 mg L-1, with a particle size range of 297 to 600 mesh. Besides the assays in a fixed bed (adsorption columns), assays were performed in a fluidized bed, which is the most used type in adsorption studies. The parameters evaluated were nitrite, nitrate, phosphate, ammonia nitrogen, COD, zinc, nickel, chromium, lead and iron. The adsorption behavior of each parameter was compared through the Langmuir and Freundlich adsorptions isotherms models. It can be verified a different behavior of the expected in the evaluation of the behavior of metals contained in the leachate. There was no adsorption, but lixiviation of the metals present in the pyrolysed oil shale. For phosphorus and organic matter was observed a considerable removal by adsorption, thus being able, be an alternative for disposal of this waste of retorting, although with the need to combine with other forms of leachate treatment for the removal of other contaminants.