USE OF RESIDUE, WASTE AND FUEL OF LOW HEATING VALUE IN CEMENT FURNACE

摘要

Utilising residual and waste materials and low calorific value fuels in cement kilns involves: (a) subjecting the materials and fuels to gasification to produce a raw gas containing volatile heavy metals, volatile salts (especially alkali metal chlorides and other alkali metal salts) and optionally hydrogen chloride; (b) subjecting the raw gas to water scrubbing to remove the volatile heavy metals as a heavy metal sulphide sludge and to dissolve the volatile salts and any hydrogen chloride; and (c) supplying the resulting gas as fuel to at least part of the heating system of the cement kiln. Gasification is effected in a stream of a free oxygen-containing gasifying medium at above the melting temperature range of the mineral components so that the latter are melted and, after cooling, form fused granules for use as cement raw material.