Abstract:
Particles of a desired mineral are recovered from particles of an unwanted mineral in an aqueous slurry by a froth flotation process in which, after treatment of the mineral particles with a collector, a predominantly hydrophobic polymeric flocculating agent, which will selectively flocculate the desired mineral particles, is added to the slurry. The predominantly hydrophobic polymeric flocculating agent may be for example a polyvinyl ether or a polybutadiene and may be predispersed in a carrier liquid, which may be the frother used to produce the froth.
Abstract:
A method for separating inorganic gangues from coal particulates dispersed in a coal refuse slurry comprises the selective flocculation of the coal refuse slurry by initially adding an anionic dispersant followed subsequently by adding an anionic flocculant, allowing the flocculating coal slurry obtained to settle and collecting a concentrated settled coal slurry having a lowered ash value. The dispersed inorganic gangues may be recovered by the addition of a cationic flocculant/coagulant with subsequent recycle of the aqueous phase.
Abstract:
A method for removing inorganic sulfides from finely ground, non-sulfide minerals is provided. A polymeric agent having a molecular weight of from about 1,000 to about 300,000 and with a plurality of xanthate groups per molecule is admixed into an aqueous suspension including inorganic sulfides and non-sulfide minerals. The polymeric agent adsorbs onto the inorganic sulfides and maintains them as a dispersion while the remaining minerals are selectively separated, as by flocculation.
Abstract:
Tailings from an oil sands hot water process extraction plant are mixed with hydrolyzed starch flocculant and transferred to a settling pond. After a residence period on the order of one year, sludge from the lower region of the settling pond is withdrawn, mixed with a hydrolyzed starch dewatering agent and transferred to a collecting pond. After a residence period on the order of one week, partially dewatered sludge is withdrawn, mixed with sand, and deposited in a terminal disposal area, the sand in the mixture there effecting an internal surcharge to obtain further dewatering. The hydrolyzed starch additives are obtained by the aqueous hydrolysis of a starch in the presence of one or more metal salts.
Abstract:
Carbonates and bicarbonates are removed from the sludge of tar sands tailings ponds whereby solids settle from the sludge more rapidly than in the presence of the carbonates and/or bicarbonates. Hydrolyzed starch is used as a flocculant in the process and alcohol may also be used to assist in the settling and/or to improve the characteristics of the settled sludge for subsequent dewatering.
Abstract:
An acidic solution containing metal values and also containing humic acid impurities, is purified by: (1) forming a gas in the acid solution, (2) adding high molecular weight anionic organic flocculant in a volume ratio of gas containing acid solution: flocculant of 1,000:0.002 to 0.10, to form a bottom, purified, aqueous acidic phase containing metal values and a top flocculated humic acid impurities froth phase and (3) removing the humic acid froth phase.
Abstract:
An iron ore is finely ground and slurried prior to being subjected to treatment with a selective flocculant for iron values. Subsequent to treatment, the iron values are allowed to settle into the underflow concentrate and be recovered. The selective flocculant employed is a hydroxymethylated polyacrylamide having a high molecular weight and a degree of hydroxymethylation in excess of about 50%.
Abstract:
Powdered coals are rapidly flocculated from aqueous suspensions by the simple addition of water-soluble starch xanthate, thereby producing a readily recoverable sediment phase and a substantially clear aqueous phase.
Abstract:
Acrylic acid polymers of specified composition and solution viscosity are selective flocculants for iron values derived from hematitic ores in the presence of non-ferrous minerals.