| 摘要 |
<p>A process for the production of titanium dioxide by dissolving titanium raw materials with sulfuric acid, producing a metal sulfate-containing titanyl sulfate solution, hydrolyzing the titanyl sulfate, separating the titanium dioxide hydrate from the metal sulfate-containing sulfuric acid by filtration, optionally bleaching the titanium dioxide hydrate by reducing treatment in acidic solution and calcining the titanium dioxide hydrate optionally mixed with doping chemicals and rutile nuclei to titanium dioxide, characterized in that the sulfate-containing titanium dioxide hydrate is dried in a dryer at temperatures from 90 to 400 °C, preferably 90 to 200 °C, especially 90 to 150 °C, and the titanium dioxide hydrate dust from the dryer exhaust is separated by filtration, the dried titanium dioxide hydrate is calcined in a rotary kiln directly heated with flue gasses at temperatures in the range from 800 to 1100 °C (solids temperature) and the exhaust is de-dusted and de-sulfurized as well as a calcining furnace for the production of titanium dioxide from dried sulphate-containing titanium dioxide hydrate in the form of a rotary kiln with a length-diameter ratio in the range of 5 to 10.</p> |
