Process and apparatus for purifying and cooling a hot gas

Abstract From the Canadian patent

Process for cooling and cleaning hot fly ash containing synthesis gas in which the gas is first passed through a cooler, the bulk of the fly ash being separated from the cooled gas in a cyclone, whereupon the gas is further cleaned in a water scrubber. A fly ash/water slurry obtained in the scrubber is at least in part injected into the crude synthesis gas. In order to avoid fouling of the cooler the fly ash particles in the hot crude gas and/or in the slurry are agglomerated preferably by adding a binder e.g. water glass.