method and installation for the continuous recovery of trivalent chromium from tannery wastewater

摘要

Method and installation to recover according to a continuous process the trivalent chrome of waste waters of teneria. Consisting of treatment of waste waters of teneria, which contain at least 0.7 per 100 cr, based to obtain a ph between 7 and 8, heating those waters at a temperature comprised between 30 degrees centigred and that of ebullición, and submitting to filtration with a rotating filter, which works continuously. The filter is provided of a filter tissue with a permeability to the air in the range of 23 to 35 liters/dm2/minute, at a pressure of 2 atmospheres. In this way, the aqueous phase extracted from the filter is substantially exempt from chromium, with which it gets a solid cake, to which sulfuric acid is added to obtain a ph less than 2.5, which, in fact, is obtained the chromium dissolution in the form of chromium sulphate. (Machine-translation by Google Translate, not legally binding)