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Show Bubble Force Makes Billions j Fortunes Extracted Daily From Froth by Treatment of Low-Grade Low-Grade Ores. GREAT SAVING OF COFFER Knowledge of Colloid and Organic Chemistry Necessary for the Flotation Flo-tation Millman Skillful Work for a Profit New York. Billions are being added to the world's wealth by the forces at work in the soap bubble. The flotation method of mineral separation, by which every day In the year fortunes are literally extracted from froth, is now exercising so powerful an influence influ-ence on mining operations in this and other countries that, according to Columbia Co-lumbia university authorities, the future fu-ture of copper production, and therefore there-fore of the electrical industry, largely hinges on bubbles. The process of ore concentration has always been considered important In mining engineering schools and the flotation flo-tation process is a leading factor in laboratory practice at Columbia, where the ore dressing laboratory is now undergoing un-dergoing considerable expansion. According to both Dean George B. Begram of the Columbia School of Mines, Engineering and Chemistry, and Arthur F. Taggart, professor of ore dressing, the advent of, flotation has worked a revolution in mining methods. meth-ods. "The word "bubble' used In connection connec-tion with mining properties formerly referred to a kind of financial management manage-ment which could hardly be tolerated in these dry and sober days, but in the last few years bubbles have taken on a new and more important significance for the larger part of the mining industry," in-dustry," said Dean Pegram. "The most important problem of the mining engineers en-gineers is usually how to concentrate the mineral In low-srrade ore to such of copper production, and therefore of the electrical industry, is very largely dependent on the same forces that are at work in the soap bubble." Professor Taggart declared that the demand for specialists in ore dressing with expert knowledge of the design and operation of the bewildering array of machinery now employed has become be-come so insistent that school curricula must be altered to offer the necessary preparatory courses. "Ore dressing is an indispensable link between mining and metallurgy in present-day practice in the extraction of metals from the eurth," said Professor Pro-fessor Taggart. "It consists in non-chemical non-chemical concentration of the valuable part of an ore into a bulk much smaller than that of the original ore, and at the same time rejection as waste of the worthless portion. "Until about fifteen years ago most mills were small as compared with present-day standards and the ores were relatively high grade. The ore treatment problem was a simple on6, and as a result the technical as well as the executive direction of the ore dressing plant could be and was incidental inci-dental to the direction with which the concentrator was built. "The services of a specialist in concentration con-centration were considered unnecessary. unneces-sary. AVith the development of the large, low-grade, disseminated copper deposits, the importance of ore dressing dress-ing took a sudden jump. These deposits depos-its contain only from twenty to forty pounds of copper per ton of ore. The ore bodies as originally discovered contained con-tained from 20:000,000 to 100,000,000 tons each of such ore. For economical working of such deposits elaborate concentrating plants, capable of handling han-dling from 5,000 to 40,000 tons of ore per day were necessary. Skillful Work for Profit. "These plants required the most skillful direction possible if a profit was to be made from their operation, and a demand for specialists in concentration con-centration immediately arose. Within the last seven years the successful ap- developed also nvichinery for sizing and dewateriug too finely ground product. prod-uct. "The men who tvill successfully handle this work must understand the physical principles underlying the operations op-erations of ore concentration, and must have, in addition, the collateral engineering knowledge essential to the designing of structures and the installation instal-lation of machinery, sufficient grasp of the principles of economics and business busi-ness to be able to judge results from a commercial standpoint, sufficient knowledge of mining to understand how ores are produced to the surface of the ground, and, finally, sufficient knowledge of metallurgy to understand the demands of the metallurgist as to the character of concentrate produced. "The instruction of such men in college col-lege then should consist In a founda- plication of processes of froth flotation to the treatment of these low-grade ores has resulted in the saving of four to six pounds more copper per ton than was formerly possible. "The advent of flotation called for a mill man of much broader scientific education than the old coccentration processes required. A flotation mill man needs a working knowledge of the newest branch of physical chemistry, chemis-try, viz., colloid chemistry, and should also have some acquaintance with organic or-ganic chemistry. Coincident with the advent of flotation In milling there has been a revolution In the methods of grinding ores preparatory to concentration. concen-tration. In the old concentration processes It was impossible to treat very finely ground ore economically. "Hence all grinding w-as done with the end in view of producing as little slime as possible. Flotation, however, works best on finely pulverized ore. Hence it was necessary, on the introduction intro-duction of flotation, to devise methods of grinding different from those at that time In use, such methods being aimed at producing slime. This resulted In the introduction of grinding machinery of an entirely different type. In connection con-nection with the new grinding and flotation flo-tation machinery there was necessarily tion of the fundamental sciences and a firm grounding In the use of the English Eng-lish language to express ideas and to present results and conclusions ; in orner words, such basic instruction as is essential to the training of all engineers. engi-neers. "On this foundation should be built a superstructure composed of courses leading to a thorough knowledge of the properties and occurrences of minerals, min-erals, to an understanding of the principles prin-ciples and simpler details of the design of structures, the generation and trans-' trans-' mission of power, the methods of mining, min-ing, the ."General principles of metallurgy metal-lurgy and the principles of economics and business finance and accounting. "Finally, following some elementary Instruction in ore dressing, the student stu-dent should be assigned a definite, fairly difficult problem In that subject, which he Is expected to carry through to a conclusion largely by his own efforts ef-forts and Initiative. "In connection with this problem there should be time in the curriculum to allow the student to elect one or more courses in some other department, depart-ment, preferably in chemistry, physics or metallurgy, such courses being along the line of the problem under investigation." an extent that the working of the ore will be profitable. A process has been developed which applies particularly to all sulphide ores, and these include most of the copper, zinc and lead ores, In which the ores may be beautifully concentrated by the action of fine bubbles bub-bles of air attaching themselves to the particles of mineral, finely ground and mixed with water. Separate Sand and Froth. "The bubbles with the sulphide mineral min-eral then rise to the top as a thick froth, while the sand and other worthless worth-less material sink to the bottom of the vessel. This flotation process has not only made much more profitable the working of the better grade of copper, zinc and lead ore, but has also made very profitable the working of ores which previously could not have been handled without actual loss. "The whole secret of the bubbles of air gathering up the mineral particles and leaving the sand depends upon treating the finely crushed ore in water with one of various chemical substances, sub-stances, among them oleic acid and pine oil. Only a very small amotfnt of the oil is necessary, less than 1 per cent by weight of the amount of mineral min-eral that Is In the ore. "After the proper reagent has been added to the water and the finely crushed ore, air is Introduced Into it either by heating It in with a stirrer or by forcing it In through fine pores In the bottom of the vessel, or any way In which to bring fine bubbles of the air into intimate contact with the fine particles of the ore. The separation Is marvelously complete, the mineral going go-ing to the top In bubbles, forming a thick froth, which Is collected by suitable suit-able arrangements, while the sand and other gangue material settles quite clean of any valuable mineral to the bottom of the vessel. "Of course the process is made to run continuously, and in some mills as much as 4.000 tons of mineral in froth is separated each day. Altogether in 1018 there wore 00,000,000 tons of ore treated by the flotation process. "I may truly be said that the future |