Design and validation of a system for hexavalent chromium adsorption in tannery effluents using orange peel and wheat bran

Abstract

This study has focused on a pilot system. A pilot capable of removing the high amounts of hexavalent chromium present in the waters of the tanning process that are dumped directly into the Bogotá River. The evaluation of bioadsorbents in synthetic water was carried out with orange and wheat bioadsorbents. To do this in the laboratory and using the Flocculator (Jar Test) and Colorimetry Techniques, the removal capacity of orange and wheat with a diameter of 850 µm at pH 1, pH 3 and pH 5 in synthetic water is validated; in this way, the conditions were selected and the adsorbent was more applied in the wastewater; finally, a pilot scale biosystem was designed and validated that simulated the laboratory conditions. The results shown in synthetic water are the most efficient conditions of the absorbents: pH 1 and pH 3 for orange with a removal of 68 % and wheat 33 %, respectively. At the time of applying the orange adsorbent at pH 1 in wastewater in the flocculator, the removal was 37 % Cr (VI), while the validation of the biosystem yielded an average efficiency of 58 % significant results for the implementation of the biosystem in the tanneries sector.