FOERFARANDE FOER ENERGIBESPARING VID TIO2-FRAMSTAELLNING.

摘要

1. Process for saving energy in the production of TiO2 by the sulphate process with recycling of the calcination off-gases, characterized in that the dust-containing calcination gases formed during the calcination are purified at a temperature higher than 320 degress C and then all or part of them are brought into contact with circulated 70 to 85 % strength sulphuric acid in a direct gas cooler, for example a jet washer, Venturi washer or washing tower, sulphuric acid with a lower H2 SO4 content being introduced into the system in such quantities that the temperature of the acid cycle remains constant and the quantity of acid circulated is kept constant by the removal of a corresponding quantity of more highly concentrated acid.