US1208171A - Concentration of sulfid ores. - Google Patents

Description

HENRY LAVERS, CAMBERWELL, ALFRED HENRY PIPER LOWRY, OFPRAHRAN, AND HENRY HOWARD GREENWAY, OF MELBOURNE, VICTORIA, AUSTRALIA, ASSIGNORS, BY MESNJE ASSIGNMENTS, T MINERALS SEPARATION AMERICAN SYNDICATE'(1913) rirmrrnii, or LONDON, ENGLAND.

CONCENTRATION OF SULFIJD'ORES.

subject of the King of England, residing at 'Camberwell Victoria Australia ALFRED HENRY PIPER LOWRY, a subject of the King of- England, and residing at Lynzala, High street, Prahran, State of Victoria,Australia,

and HENRY HOWARD GREENWAY, a subject of the King of England, residing at Melbourne, Victoria, Australia, have invented certain new and'useful Improvements in the Concentration of Sulfid Ores, of which the following is a specification.

This invention relates to certain improvements in the concentration of sulfid ores, and refers more especially to the concentration of mixed zinc and lead sulfid ores, that is to say ores containing a mixture of galena and blende with gangue. In this specification the term ores is intended to include concentrates, tailings, slimes, and other products containing metallic sulfids.

This invention rel-ates to the concentration of sulfid ores by flotation separation, and more especially to froth flotation separation, in which a froth of sulfids is floated to the surface consequent upon the aeration or' agitation of the ores in the presence of a suitable frothing agent (such as an essential oilfor instanceeucalyptus oil).

Hitherto froth flotation separation of the mixed sulfids from the gangue has generally been conducted withthe addition of acid to the circuit water. With certain ores known as calcitic orescontaining carbonates the consumption of acid has in some instances largely added to the cost of treatment. This applies especially to slimes, as the acid consuming substances (such as calcite, &c.) are mostly found with the finely divided slimes. An alkaline medium or circuit water has been adopted in some cases, and, under certain conditions, for the differential or preferential flotation separation of certain sulfids from other sulfids, but so far as we are aware, a flotation separation of mixed sulfids generally from the gangue has not been effected with the employment in solution in the pulp of an alkaline selectivity-modifying agent. It has previously been proposed to eflect the concentration of copper ores by the agitation froth process by agitating the ore sus- Specification of Letters Patent.

' ture.

Patented nee. i2, rare.

Application filed March 14, 1914. Serial No. 824,765.

pended in Water with a minute quantity of an aromatic hydroxy compound to beat in air and form a froth, at the same time adding to the circuit solution a small proportion of an alkali to facilitate the solution of the aromatic hydroxy compound employed as a frothing agent.

We have discovered that if a finely pulverized ore is submitted to flotation separation with agitation and aeration and with a suitable frothing agent (such as an essen tial oil, for instance eucalyptus oil) in Water containmg in solution an alkaline substance,

cient to insure the formation of a mineral bearing froth.

"such as carbonate of soda, a froth of the metallic sulfids will rise to. the surface and The question as to whether in the treatment of any particular ore in a certain circuit water the addition of an organic frothing agent is necessary can be determined by a simple laboratory test.

If desired the resultant products may be retreated with or without the addition of fresh quantities of the substances referred to.

As an example of the application of this process We may mention certain experiments which have been conducted by us A. One pound of slimes assaying 14.4% lead, and 14.6% zinc, was submitted to flotation separation with agitation and aeration in l lbs. of water containing in solution carbonate of soda equivalent to 224 lbs. per ton of slimes treated, to which was also added eucalyptus oil equivalent to 0.6 lbs. per ton of slimes. The charge was thoroughly aerated by being agitated in such a way as to disseminate air through the mix- On bringing the mixture torest, a froth of mixed concentrates was obtained assaying 26% lead, and 29.8% zinc, leaving a residue assaying lead, and 2.2% zinc.

B. A parcel containing one ton of slimes from Broken Hill assaying 11% lead and ing agitated in about four (4) tons of water contain'ing'an amount of soda ash equivalent to 35 lbs. per ton of ore treated, and eucalyptus oil equivalent to three-quarters (if) of a lb. per ton of ore treated at a temperature of from 125 to 130 F. A froth of mixed sulfids was Obtained assaying- 18.5% lead and 27.4% zinc, being a recovery of 90% lead and 94% zinc- These float concentrates were retreated with small additions of eucalyptus oil and soda ash to the circuit Water equivalent to 0.1 lbs. and

.4 lbs. respectively per ton of ore treated while. the temperature was maintained at about 125 to 130 F., when a fr h of mixed sulfids was obtained assaying 2.4% lead and 35.8% "zinc, being a recovery of 84.3% lead and 90% zinc.

0. Two lbs. of Broken Hill slimes were mixed with 7 lbs. water at 130 F., and soda ash equal to.22.4 lbs. per ton of the slimes. The mixture was then thoroughly aerated by being agitated, with the result that a mixed concentrate assaying 29.5% lead, 35.2% zinc, 25.0 ozs. per ton silver was produced, giving recoveries of 90.0% lead, 92.7% zinc, and 91.5% silver. In this test -no frothing agent other than soda ash was added. I

D. Two lbs. of Queensland copper ore tarnished by weathering and unsuitable for ordinary flotation treatment assaying 2.9% copper (of, which 0.5% copper was oxidi zed) 6.5 dwts. per ton gold were mixed with 7 lbs. water at F. containing soda ash equal to 33.6 lbs; per ton of the ore and a mixture of about equal proportions of eucalyptus oil and mineral oil equivalent to 2 lbs. per ton of ore. The whole was then thoroughly aerated by bein agitated with the result that a froth of mixed sulfids was obtained assaying 11.3% copper, 26.1 dwts. gold, being a recovery of 74.4% copper, 76.7% gold.

The concentrates obtained by this invention are found to be in a most suitable condition for preferential flotation separation of one of the sulfids from the other sulfids by one of the known methods, more especially one employing an alkaline separating medium. Though it has been found that the above method is especially applicable to the treatment of slimes, it is not confined to the treatment of that class of ore,but is applicable to coarser material also.

This method of, treatment is especially applicable to cases where by reason of the state of the ore due to oxidation by exposure or weathering (such as accumulated dump slimes and tarnished ores), the use of acid is inadvisable, and neutral'circuit water is unsuitable.

The alkaline substances most suitable for addition to the circuit water are the carbonates of the alkaline metals, but other alkalis may be'used. We prefer in most cases the crude sodium carbonate or soda ash. The amount of alkaline substance added to the circuit water should in all cases be sufliamount of soaps which tend to form an indiscriminate froth of sulfids and gangue. We therefore prefer to use a frothing agent other than a fatty'acid.

In the following claims the terms substantially all the floatable metalliferous minerals and substantially all the floatable zinc and lead are intended to mean such a recovery of metalliferous mineral or of zinc and lead together as is practically obtainable in a procedure which aims to float all the metalliferous mineral as differentiated from preferential selection of one metalliferous mineral from another.

What we claim as our invention and desire to secure by Letters Patent is 1. A process of concentrating ores con: taining mixed metalliferous minerals which consists in agitating and aerating a pulp of such an ore, such pulp containing 1n solution an alkaline selectivity-modifying agent, so as to obtain a froth of concentrates of substantially all thefloatable metalliferous minerals while the gangue sinks, said solution being alkaline during separation of the minerals, and separating the froth, whereby the metalliferous minerals are separated from the gangue.

2. A process of concentrating ores containingmixed metalliferous minerals which consists in agitating and aerating a pulp of such an ore, such pulp containing in solution an alkaline selectivity-modifying agent and also containing a small proportion of a frothing agent, so as to obtain a froth of concentrates of substantially all the floatable metalliferous minerals while the gangue sinks, said solution being alkaline during separation of the minerals, and separating the frotlnwhereby the metalliferous mineralsare separated from the gangue.

3. A process ofconcentrating ores containing mixed metalliferous minerals which consists inagitating and aerating a pulp of such an ore, such pulp. contalnlng in solu minerals, and separating the froth, whereby the metalliferous minerals are separated from the gangue.

4. A process of concentrating ores containing mixed metalliferous minerals which consists in agitating and aerating a pulp of such an ore, such pulp containing in solu-- tion a carbonate of an alkaline metal and also containing a small proportion of a frothing agent, so as to obtain a froth of concentrates of substantially all the floatable n'ietalliferous minerals while the gangue sinks, said solution being alkaline during' separation of the minerals, and separating the froth, whereby the metalliferous mineralsare separated from the gangue.

5. A process of concentrating ores containing mixed metalliferous minerals which consists in agitating and aerating a pulp of such an ore, such pulp containing sodium carbonate in solution so as to obtain a froth of concentrates of substantiallyallthe float while the gangue sinks, said solution being alkaline during separation of the minerals, and separating thefroth, whereby the metalliferous minerals are separated from the gangue. p

7. A process of concentrating zinc-lead ores which consists in agitating and aerating a pulp of such an ore, such pulp containing in solution an alkaline selectivity-modifying agent, so as to obtain a froth of concentrates containing substahtially all the floatable zinc and lead while the gangue sinks, said solution being alkaline during the separation of the minerals, and separating the froth, whereby the zinc and lead are separated from the gangue.

8. A process of concentrating zine-lead ores which consists in agitating and aerating a pulp of such an ore, such pulp containing in solution an alkaline selectivity-modifying agent and also containing a small proportion of a frothing agent, so as to obtain a froth of concentrates containing substantially all the floa'table zinc and lead while the gangue sinks, said solution being-alka line during separation of the minerals, and

separatingthe froth, whereby the zinc and lead are separated from the gangue.

9. A process of concentrating zinc-lead ores which consists in agitating and aerating a pulp of such an ore, such pulp containing in solution a carbonate of an alkaline metal, so as to obtain a froth of concentrates containing substantially all the fioatable zinc and lead while the gangue sinks, said solution being alkaline during separation of the minerals, and separating the froth, whereby the zinc and lead are separated from the gangue.

' 10. A process-of concentrating zinc-lead ores which consists in agitating and aerating the pulp of such an ore, such pulp containing in solution a carbonate of an alkaline metal and also containing a small proportion of a frothing agent, so as to obtain a froth of concentrates containing substantially all the floatable zinc and lead while the gangue sinks, said solution being alkaline during separation of the minerals, and separating the froth, whereby the zinc and lead are separated from the gangue.

11. A process of concentrating zinc-lead ores which consistsin agitating and aerating a pulp of such an ore, such pulp containing sodium carbonate in solution, so as to obtain a froth of concentrates containing substantially all the floatable zinc and 'lead while the gangue sinks, said solution being alkaline during separation of the minerals, and separating the froth, whereby the zinc and lead are separated from the gangue.

12. A process of concentrating Zinc-lead- "ores which consists 1n agltating and aeratingv a pulp of such an ore, such pulp containing sodium carbonate in solutiorr and also containing a small proportion of a frothing" agent, so as to obtain a froth of concentrates containing substantially all the floatable zinc and lead while the gangue sinks, said solution being alkaline during separation of the minerals, and separating the froth,

whereby the zinc and lead are separated