Treating kieselguhr slurry for filter use

摘要

In prepn. of kieselguhr for de-watering and filtration a feed slurry is dried in a warm gas stream before entering a cyclone for sepg. large particles. The fine dry fraction is heat treated while forming the fluidised bed in a reactor, pref. with a pear shaped chamber heated by liq. and/or gaseous fuel combustion, and with a coaxial lance to inject dry material. A further cyclone clad with refractory ceramic separates about 80% of the solids, which are finally cooled. Discharged gases from the cyclone are returned to the initial warm gas drying stream, the piping which is cooled by sprayed water to the appropriate drying gas temp. water temp. is subject to a process controller.