Sept., 1922
T H E JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY
Few engineers outside of the sugar industry appreciate what can be done by a proper interlocking of power units, evaporating units, and heating units. Such economies are possible, when this group of operations is considered as a whole as no power specialist and few heating or evaporating specialists realize. For instance, in beet-sugar manufacture, 12 to 15 per cent coal is burned (calculated on the weight of the beets) in the best practice in this country. It is said that 9 per cent is reached in Germany, but German mills do not produce 21 finished sugar. There is a mill in this country which wai3 well built by a good sugar engineer. It has been operated for some years by wholly untrained superintendents. Owing mainly to a lack of knowledge of how to coordinate
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the power, heating, and evaporating units, the fuel consumption has risen year by year (as the original design in the mill has been altered) until last season it used 25 to 30 per cent coal on the weight of the beets. There are many other similar fields in chemical engineering which need extensive work. Practically all of the unit operations are in the same state as heat transfer. Distillation and drying are receiving considerable attention at present. Mixing and stirring have not been touched; filtration has been worked on only enough to outline the problems; in fact, chemical engineering, as such, is still in almost every phase a new and undeveloped field.
The Vegetable Oil Industry By David Wesson TECHNICAL D I R ~ C T OTHB R , SOUTHBRN COTTONOft Co., NEW YORK,N. Y
HE PAST two years have brought to light few, if any, great changes in products or manufacturing methods, though a great deal has been done toward improving existing methods with a view of securing greater economy of operation and improvement of product. I n the matter of solvent extraction there has been considerable progress in Europe. I n England there is a large plant operating on palm kernels and copra, producing upward of 80 to 100 tons of edible oil per week. I n this country one or two large plants, which were highly successful during the war, have closed down on account of peace conditions. The manufacture of by-product coke has made available large quantities of benzine at a reasonable price. This is an ideal solvent for peanuts, copra, palm kernels, and other seeds that are free from coloring matter. The petroleum people are giving attention to the production of a fraction with low boiling point distilling within close limits, also suitable for this purpose. The literature discloses twenty or more patents mostly relating to apparatus. A novelty is the proposal by McKee to use sulfur dioxide as the extraotion medium.l In refhing the oil various innovations have been presented for removing the free fatty acids in such a manner as not to saponify neutral oil or carry out the same with the soap formed in the usual method of saponification. E. R. Balton and E. J. Lush2 convert free fatty acids into glycerides by heating to 200” t o 250” C., and treating with glycerol vapor. They claim that the resultant neutral fat can be refined. H. Schlinck and Company3 neutralize the fatty acids by boiling the fat containing same with glycol under a reflux condenser using 11 per cent glycol by weight of the fatty acids present, a,nd removing the water formed by operating in vacuum or passing an inert gas. They also add asuitable catalyst and pass hydrogen to hydrogenate at the same time. C. and G. Muller Speissefett fbr. A. G.4 dissolve the fat in a solvent ‘miscible in water, such as acetone, then add sufficient water to precipitate the neutral, leaving the fatty acids in solution. The solution of fatty acids is drawn off and more water added to precipitate them. L. Schmidt6 dissolves the oil in a suitable solvent, then
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1
U. S. Patent 1,376,211.
1
Brit. Patents 159,587, 163,352 (1919).
a Ger. Patents 334,659, 315,222 (1916). 4
Ger. Patent 339,027 (1918). 1,395,998 (1921).
5U. S.I’atent
agitates with alkali and removes the resultant soap by filtration. The process is said to be operated in Switzerland, Italy, and Germany. The bleaching of oils for edible purposes continues to be done mostly with fuller’s earth, with or without the addition of bleaching carbons in some of the various forms. A large variety of fuller’s earths are now on th6 market. Most of them are natural products prepared by drying and grinding, while others are made by action of sulfuric acid on suitable clays. Some of these artificial earths have marked bleaching properties. The past two years have witnessed a large number of new bleaching carbons mostly of vegetable origin, made by the treatment of waste materials. Some D A V I D WZ%3ON of them pound for pound are far more active than boneblack, but their increased activity is largely offset by advanced price. This operation of hydrogenation seems to be pretty well standardized, though numerous patents have been taken out on apparatus and catalysts. Electrolytic hydrogen seems to have been pretty generally adopted. The low prices of hard animal fats have largely curtailed the output of hydrogenated oils. Vitamins have been very much in the limelight the past two years. Many new facts have been discovered and many of the previous exaggerated ideas exploded. Dr. H. C. Shermanin his recent work, “The Vitamins,” published by the Chemical Catalog Co., gives a fair summing up and classification of most of our knowledge to date on this matter, so voluminous in the literature and so meager in exact chemical facts. Dr. Casimir Funk in an address before the Institute d Mar-
