US 1773997 A
Description (OCR text may contain errors)
Patented Aug. 26,- 1930 V I I umr'eo 154mm omen WILL! 1).
GREEILOF BAUER, UTAH, AssroNoR T COMBINED METALS REDUCTION communion s'roox'rori, UTAH, A oonrormrron or UTAH PROCESS non 'rrm nxraaorrou or nnsm anon COAL R o Drawing. Application fled April 19,
' There are certain coals which contain a valuable resin. Heretofore, it has been pro-- posed to extract the resin by means of solvents such as benzol. This method is exensive and wasteful of the solvent used. It as also been kproposed to separate the resin from the coal '3 use of liquids with high specific gravities. he contamination of the productsand mechanical losses of the liquid 1' used make a procedure of this kind expen-' slv'e.
This invention is based upon the discovery that the relative flotability of resin is enough greater than that of coal that the resin can be effectively floated from coal by a suitable flotation agent such as one of the higher alcohols, turpentine, cresol, or one of the pine oils, or the like.
I have found that amyl alcohol is particularly advantageous as the frothing agent for the separation of resin from coal, although other recognized frothing agents may be used. I find that amyl alcohol gives a cleaner resin and a better recovery than the other fr'cthing agents named. I
I have'also found that the resin froth conoentrate produced by using one of these frothin agents contains appreciable quantities 0F finely divided coal which lowers the grade of the resin, and if the resin is refioated in the presence of a small amount of potassium alum mostof this finely divided coal can be eliminated and a high grade resin obtained. The highly concentrated resin so obtained can now be, dissolved in suitable solven'ts for making varnish or lacquer or for other purposes and the resin solution further purified by centrifugal separation, filtering or other means. 4e The invention involves treatin the resincarrying coal, reduced to a flotab e size, i. e., of a size sufficiently fine to liberatethe resin from the coal, and in the form of a water pulp with a small quantity of am 1 alcoholor other frothing agent in a flotation machine 1829. Serial No. 856,623.
or a paratus, whereupon the resin collects in the orm of a froth and can be removed in the usual manner. 4
. The coal remains in the pulp as the tailing andl can be recovered and used as powdered coa The resin froth which carries some very finely divided coal can be mixed with a suitable quantity of water, a small quantity of potassium alum added and the resin refloated in another flotation machine or apparatus thus making a clean resin, the finely divided coal remaining in the pulp as tailing.
In carrying out the invention, it is preferable to use cold water because amyl alcohol is a solvent for resin and its solvent action is facilitated by heat, although thisis not a necessary limitation of the invention.
The following example illustrates the practice of the invention:
500 grams of resin-bearing coal from Salina Canyon, Utah, was ground with 2cparts of water to approximately pass a 40-mesh screen, which in this case was sufliciently fine to liberate the resin from the coal. An addi tional quantity of water, sufficient to give a 1: 3 pulp, was added and the pulp introduced into a froth flotation machine. Here amyl alcohol was added in the proportion of 0,6 pound per ton of resin-bearing coal and the whole agitated in the usual manner. A froth formed which carried the greater portion of the resin and was removed, the coal remaining in the pulp vas a tailing.
The resin froth was now prepared for and subjected to selective flotation treatment that is, the resin froth was introduced into a flotation machine, water added in sufficient quantity to fill the machine to workin level, 0.4 pound of potassium alum perton o original resin-bearing coal was added, the whole agitated, then 0.2 pound of amyl alcohol per ton of original resin-bearing coal was added, and a new clean resin froth was thus formed, which was removed in the usual manner.
resin from resin-bearing coal, wh1ch com- The following table shows the results. a four tests: v
Test 1 Test 2 name 'r wt. wt. wt.
Resin coal 100. o; 100. o 100. 100. e Resin 96% pure froth concentrate. 7. 2 7. 0 7. 1 6. 9 Taillnz-Coa1 residue 92.8 as. o v 92.9 93.1
After the removal of the resin by froth flotation, vthe coal tailing or residue can be, used directly as powdered coal fu p What I claim is:
1. The method of effecting separation of" resin from. resin-bearing: coahawhich com: :1 prises comminuting such coal and forming aux. 'pulp thereof, adding tosuch 'pulp a frothing agent that has a greater. afiinity for resin than forcoal and subjecting the same to froth flotation treatment such frothing 'agent-being" used inzqua-ntity sufficient to float most of the resin but insufficient to-float much of the coal.
2. The method of recovering-resin from resi-n bearing coal, whlch consists in comminuting such coal and form ng a pulp thereof,
adding to such pulp a flotation agent of the class'which includes higher alcohol, turpentine, cresol and pine oil, in the proportion of about six-tenths of a pound of such flotation agent to a ton of coal and subjecting thepulp to froth flotation treatment.
3. The method of effecting separation of resin from resin-bearing coal, which co'mprises comminuting such coal and forming a pulp thereof, adding amyl alcohol to such pulp in the proportion of about six-tenths of a pound of aniyl alcohol to a ton of coal and subjecting the same to froth flotation treatment. I p 4 4. The method of effecting separation of prises comminuting such coal and forming a pulp thereof, addinga frothing agent to such pulp and subjecting the same to froth flotation treatment'to form a resin froth, placing said froth in a flotation machine, adding to the froth sufficient water to fill the flotation machine to working level together with about four-tenths of a poundof potassium alum per ton of originalf coal, agitating the same, and
then adding about two-tenths of a pound of amyl alcohol per ton of resin bearing coal and subjecting the mixture to froth'flotation.
5. The method of recovering resin from resin-bearing coal, whichconsists in commiouting such coal and forming a pulp thereof,
adding to such pulp a flotation agent of the class which includes higher alcohol, turpentine, cresol and pine oil, in the proportion of about six-tenths of a poundof such flotation agent to a ton of coal and subjecting the pulp to froth flotation treatment to'form a resin froth, placing said froth in a flotation machine, adding to the froth sufficient water to v fill the flotation machine'to working level togather with about four-tenths of a pound of -potassium alum per ton of original coal, agitating the same, and then adding about twotent hsof a pound of amp} alcohol per ton of resin bearing coal and en jectingtheniixture to froth flotation.
6'.vThe method of effecting separation 'of resin from resin-bearing coal, which com-.1
prises comminutin such coal and forming a pulp thereof, adding amyl alcohol to such pulp in the proportion, of about six-tenths of a pound of aui'ylijalcohol to azton'of coal and subjecting the same to froth flotation treat-- merit to form a resin froth, placing said froth in a flotation machine,.iadd.ing to theafroth' suflic'ient water to fillthe flotation machine to working level together with about four-tenths of a pound of potassium alum per ton of original, coal, agitating the same, and then add ing about'two-tenths of a pound of Uhyftlcdsubject- I hol per ton of resin-bearing coal and ing the mixture to froth flotation. I
7. The method of recovering resin from resin-bearing coal which consists in formin such coal into a water pulp and subjecting the same to ordinary froth flotation treatment to form a resin froth, forming'said froth into a pulpby adding water thereto together with potassium alum in the proportion of about six-tenths of a pound thereof to a ton of the original coal and agitatin the same, and then adding a fresh sup 1y 0 frothin agent in the proportion of a out two hun r'edths of one percent thereof to a ton of the original 00:11 and forming a new resin froth.
8. The method of effecting separation' of resin from resin-bearing coal which com-' prises comminuting such coal and forming a pulp thereof, addin suitable flotation agents to such pulp and su jecting the same to froth flotation treatment to form aresinfroth, re-
.ing a coal depressant and a frothing agent to the pulp and then floating the resin.
Signed at Stockton,'Utah, thisvl2th day of April, 1929.
WILLIAM D. GREEN.