US2094646A - Flotation reagent - Google Patents

Description

Patented Oct. 5, 1937 UNITED STATES FLOTATION REAGENT No Drawing.

Application December 13, 1935,

Serial No. 54,352

8 Claims.

This-invention relates to the process of recovery of coal or other carbonaceous minerals such as hard carbon, and either natural or artificial graphite from water pulps, and has reference specifically to the reagent employed .in effecting such froth flotation or separation.

This application .is a continuation-in-part of I my copending application, Serial No. 586,250, filed January 12, 1932, for Coal flotation process, Patent No. 2,028,742 of January 28, 1936.

In the froth flotation process, as usually practiced, ore or other mineral, in finely-divided condition is suspended in a liquid carrier and subjected to aeration and agitation in the presence of an agent having a preferential affinity for one or more of the constituents of the pulp with the result that the material so acted upon is carried upwardly by the bubbles thus formed, and concentrated on the surface in the form of a froth.

Various types of flotation agents are used in the froth flotation of ores and these may be employed to perform different functions in different treatments, such as frothing, collection, promotion and selection.

This invention relates more particularly to a reagent for use in a froth flotation method of carbonaceous mineral separation, and by means of which a substantially clean separation of coal and other carbonaceous minerals, in aqueous suseffected.

One object of this invention is to provide a reagent consisting of a plurality of ingredients whose proportions may be effectively varied through a wide range to adapt it to a variety of treatments.

Another object of this invention is to provide a reagent capable of floating a given amount of coal, or other carbonaceous mineral, in the pulp under treatment, thereby permitting very close control of the flotation operation by adding the reagent to the pulp progressively in quantities proportionate to the coal content of the pulp.

These and other objects will more fullly appear in the course of the following description.

, While the present invention is adapted'for use in the froth flotation treatment of various minerals, it is particularly suited for use in coal flotation operations. l

The reagent produce in, accordance with the present invention comprises'a' mixture of crude paraffin base petroleum .oil and common commercial kerosene in substantially equal parts, mixed. with a comparatively small amount of coal-tar creosote.

pension, from extraneous matter can be readily Used alone, neither the crude oil, the creosote rior the kerosene is a good flotation reagent for coal. Crude oil is a collector with weak frothing action. Cr-eosote is a weak collector, but a strong and active frother that is very hard to control.

Kerosene has weak frothing action and very little collecting action, but has the valuable property of speeding up the collecting action of crude oil and stabilizing the frothing action of the creosote.

When combined in the manner hereinafter described, these compositions form a reagent which serves to produce frothing, collection, promotion and selection in the froth flotation treatment of raw coal, coal-washery sludges, refuse or the like.

Mixtures of crude oil and creosote, crude oil and kerosene, creosote and kerosene used alone are ineffective to produce satisfactory results. Best results are attained when the crude oil and kerosene are initially mixed and allowed to stand for at least fifteen minutes before using. Thereafter the mixture is introduced into the pulp and immediately prior to or during its entry into the material under treatment, the creosote is introduced into the same.

A decided chemical reaction results when the crude oil-kerosene mixture is brought together with the creosote andthe best flotation results are obtained when this reaction takes place in the flotation machine.

The crude oil-kerosene mixture may be stored for long periods without deterioration and the same is true of the creosote. When the two are brought together, the chemical action resulting, changes the composition so that subsequent contact with air will cause a deposit of gummy material out of the liquid body.

For this reason, it is desirable to keep the crude oil-kerosene mixture and the creosote separated until such time as they are to be used in the process, and in this way the full benefit of the reaction influence is obtained.

Any crudeparaflin base oil may be used but the crude oil from the Florence, Colorado field is particularly efficacious. Any standard grade commercial kerosene is satisfactory. The coal tar creosote producing best results has a specific gravity of 1.054, a'boiling point of 210 'C., and a solid residue of 18% to 19% at 355 C.

These materials constitute the preferred ingredients of the reagent, but any compositions coming within the general definitions will give satisfactory results.

While I do not wish to be limited to specific proportions, good results are obtained by using from 3% to lil% by volume of creosote with from 90% to 97% of the crude oil and kerosene mined in substantially equal amounts.

The amount of the reagent to be used in the process depends upon the character oi the mate-=- rial under treatment, and whether large or small quantities are to be floated in any particular cell. For example, in treating coal, 90% of the coal content of the pulp can be floated in the first cell of the machine by using a suficient quantity oi reagent, but in so doing, considerable amount of ash content is carried into the froth.

'Wl iere lesser amounts of reagent are used, a smaller percentage of coal will be floated in the first cell, but a clean separation between coal and ash content will result. Theamount of reagent used to treat a ton of coal will normally be from five to eight pounds, or substantially one gallon per ton treated.

The reagent above described, although primarily intended for use in the froth flotation 2. A froth flotation reagent comprising es- 7 sentially the product obtained by mixing a mixture of crude parafin base petroleum oil and kerosene with coal tar creosote, said coal tar creosote being combined with the other in gredients in the presence or a flotation pulp.

- 3. A froth flotation reagent comprising essen tially the product obtained by mixing substan=- acces -re tially equal parts of crude parafin base petro== leum oil and kerosene, constituting from 88% to 97% of the reagent composition, with coal tar creosote constituting from 3% to 12% oi the same.

i. A froth flotation reagent comprising essentially the product obtained by mixing crude paraffin base petroleum oil, and kerosene with coal tar creosote having a specific gravity of substantially 1.054, a boiling point of substantially 210 centrigrade, and a solid residue of substantially 18% at 355 centigrade.

5. A froth flotation reagent comprising essentially the product obtained by mixing four parts crude paraiiin base petroleum oil, four parts kerosene, and one part coal tar creosote.

, 6. A froth flotation reagent comprising essentially the product obtained by mixing crudeparaiffin base petroleum oil and kerosene with a sumcient quantity of coal tar creosote to produce a chemical reaction between components of the reagent, said coal tar creosote being combined with the other ingredients in the presence of a flotation pulp.

7. A froth flotation reagent comprising essentially the product obtained by mixing crude paraffin base oil and coal tar creosote with a suflicient quantity of kerosene to accelerate the collecting action of the crude oil and to stabilize the frothing action'of the creosote, said kerosene being combined with the other ingredients in the presence of a flotation pulp.

8. A froth flotation reagent comprising the reaction product obtained by bringing together in the presence of a flotation pulp, substantially equal parts of crude parafiin base petroleum oil Pm M. en.