Abstract The separation of humates and silica from sands containing ilmenite (FeO.TiO2) and other heavy metals during ground level dredge mining of FeO.TiO2 from ancient beach sand wherein the tailings as discard contain organic matter, largely humates, as colloidal dispersion, together with a major amount of silica present as a slurry which is forwarded to conduits and piles. This improved process comprises adding to the tailings 6-400 ppm of an organic cationic condensate and particularly a polymeric cationic organic amine. Preferred polymers or condensates are epichlorohydrin (epi)/ammonia and ethylene dichloride/dimethyalamine (DMA) quaternized with methyl chloride. The concurrent use of high shear agitation in mixing the cationic condensate with the tailings dispersion as, for example, utilizing the mixture as input to the suction side of a centrifugal pump, allows the amount of cationic treating agent to be drastically reduced from a range of about 240-400 to 6-50 ppm. Further, the incorporation of the treating agents into a type of closed cycle or no-exit process where the tailings are piled up in a contiguous area of the mining operation has definite advantages over prior processes because the colored humate values are now in part or wholly bound to the silica and the return water is clarified. Furthermore, the eventual use of the tailings pile with the bound humate now permits reforestation.
IN A PROCESS FOR THE RECOVERY OF LIMENITE FROM ANCIENT BEACH SANDS BY DREDGE GROUND LEVEL MINING WHEREIN THE SANDS ARE CLASSIFIED IN A WET MILL TO PRODUCE AN ILMENITE CONCENTRATE AND A TAILINGS STREAM, SAID TAILINGS STREAM CONSISTING OF A DISPERSION OF WATER, COLLOIDAL HUMATE AND SILICA THE IMPROVEMENT COMPRISING ADDING TO SAID TAILINGS STREAM DISPERSION WITH AN EFFECTIVE AMOUNT OF HIGH SPEED AGITATION A WATER-SOLUBLE POLYMERIC CATIONIC AMINE OF MOLECULAR WEIGHT OF ABOUT 20,000 TO 100,000 IN AN EFFECTIVE AMOUNT OF ABOUT 6-400 PPM TO CAUSE THE FLOCCULTION OF SAID HUMATE RETENTION IN THE TAILINGS,
Claim 2
Dependent Claim
97 words
IN A PROCESS FOR THE RECOVERY OF LIMENITE FROM ANCIENT BEACH SANDS BY DREDGE GROUND LEVEL MINING WHEREIN THE SANDS ARE CLASSIFIED IN A WET MILL TO PRODUCE AN ILMENITE CONCENTRATE AND A TAILINGS STREAM, SAID TAILINGS STREAM CONSISTING OF A DISPERSION OF WATER, COLLOIDAL HUMATE AND SILICA THE IMPROVEMENT COMPRISING ADDING TO SAID TAILINGS STREAM DISPERSION WITH AN EFFECTIVE AMOUNT OF HIGH SPEED AGITATION A WATER-SOLUBLE POLYMERIC CATIONIC AMINE OF MOLECULAR WEIGHT OF ABOUT 20,000 TO 100,000 IN AN EFFECTIVE AMOUNT OF ABOUT 6-400 PPM TO CAUSE THE FLOCCULTION OF SAID HUMATE RETENTION IN THE TAILINGS,
Claim 3
Dependent Claim
15 words
The method of claim 1 wherein the polymeric cationic amine is a condensate of epichlorohydrin/-dimethylamine.
Claim 4
Dependent Claim
20 words
The method of claim 1 wherein the polymeric cationic amine is a condensate of ethylene dichloride/ammonia quaternized with methyl chloride.