Energy consumption in the sulfate process for producing titanium dioxide is reduced

摘要

The moist metatitanic acid filter cake is passed into a drier for pre-drying before entry into the furnace for calcining. The cake is first dewatered to between 55 and 65% moisture. The pre-drying at 100 to 160 deg C brings the residual moisture level to between 5 and 25%. The waste gas from the calcining furnace is used to heat the drier. The pre-dried filter cake has a mean particle size of from 0.1 to 4 mm immediately before entry into the calcining furnace.