Najsos

Claim 1

IN THE METHOD OF ROASTING NICKELIFEROUS SULFIDE, SUCH AS NICKELIFEROUS PYRRHOTITE CONCENTRATES, THE IMPROVEMENT WHICH COMPRISES MAINTAINING A HOT FLUIDIZED BED OF AGGLOMERATES IN WHICH ROASTING TAKES PLACE AUTOGENOUSLY AND FROM WHICH HOT ROASTING GASES RISE CONTINUOUSLY INTO THE FREEBOARD SPACE ABOVE THE BED, SPRAYING AN AQUEOUS SLURRY CONTAINING THE NICKELIFEROUS SULFIDE CONCENTRATES AND A BINDING AGENT WITH COMPRESSED AIR INTO THE FREEBOARD SPACE TO PRODUCE A MULTIPLICITY OF SMALL DROPLETS CONTAINING A PLURALITY OF THE CONCENTRATE PARTICLES WHICH DECEND DOWNWARDLY THROUGH SAID FREEBOARD SPACE IN COUNTERCURRENT CONTACT WITH THE RISING HOT GASES FROM THE BED, THE HOT GASES FIRST EVAPORATING WATER FROM THE DROPLETS TO CONVERT THEM INTO WET AGGLOMERATES IN WHICH THE CONCENTRATE PARTICLES ARE BONDED BY THE BINDING AGENT AND THEN EVAPORATING WATER FROM THE WET AGGLOMERATES TO FORM DRY AGGLOMERATES WHICH ON CONTINUED DESCENT THROUGH THE HOT GASES ENTER THE FLUIDIZED BED VENTING THE RESULTING MIXTURE OF VAPORS ALND GASES FROM THE UPPER PORTION OF THE FREEBOARD SPACE, AND REMOVING THE AGGLOMERATES FROM THE FLUIDIZED BED AFTER THEY HAVE BEEN ROASTED THEREIN.