polyethylene and the entry of England's Albright & Wilson into the silicone field by way of licenses from the U. S. In general, the purchasing of other companies' processes has the advantage of yielding far quicker returns than the slow, laborious procedures of pioneering research. On the other hand, the results may not be quite so profitable. Diversification can also be brought about by the outright purchase of other companies or through mergers. Examples are Olin Mathieson's move into the drug field by the purchase of Squibb, and Monsanto's entrance into the petroleum field through acquisition of Lion Oil. Here again, results are rapid. At the same time, not only does the company gain new products but also much needed, experienced personnel. The Federal Trade Commission estimates that about 2 5 % of the approximately 2000 mergers and acquisitions that took place in the U. S. from 1951 to 1954 were undertaken for the express purpose of diversification. The avalanche of mergers that occurred in the chemical industry during the past few years has clearly been an outgrowth of the urge to diversify. Of course, there are also definite limitations on how far companies can diversify. There are the obvious dangers of diversifying into fields in which a company has little or no experience or no special advantages, such as nearness to markets or readily available supplies of low-cost raw materials. Furthermore, there is the basic problem of getting enough capital to make diversification possible. Many companies deliberately shy away from diversification if it means introducing products manufactured by their customers. They believe their function should be solely to produce raw materials and intermediates—and let their customers turn out the finished products. On this question, opinion in the chemical industry is sharply divided. Many chemical firms are convinced that competition with one's customers is no cause for real concern. Diversification, they say, has progressed to the point today where, in many cases, a purchaser of chemicals would be forced to go to a less desirable source of supply if he insisted on buying raw materials from a noncompeting company—which is 14 A
seldom worth while. Many chemical firms very successfully sell both intermediates and finished products. Examples: Cyanamid's sale of dye intermediates and finished dyes, Rcichhold's sale of resin intermediates and finished resins, Monsanto's sale of detergent alkylates and the household detergent All. Of course, companies can also ovcrdiversify. Product lines may be added that eventually prove insufficiently profitable. Because of this, Ethyl Corp. discontinued producing agricultural chemicals, Heyden sold its plant for the manufacture of antibiotics, USI sold its facilities for the production of insecticides. In the main, however, companies find that product diversification is enormously desirable and certainly one of the surest roads to growth.
I/EC Water Savers Cooling towers save a lot of water, but makers would like them to save more. Standards are a starting point. I o MAKE 150 tons of butadiene in a day, you need roughly 57 million gallons of cooling water. But plant location economics, and water supply and pollution problems, leave few sites where you can use that much water, on a oncethrough basis, to make butadiene or anything else. One result is more and more stringent demands on water re-use devices like cooling towers. And cooling tower makers are moving steadily toward comprehensive design and performance standards for their product. Prime mover is the Cooling Tower Institute, formed in 1950 at Palo Alto, Calif. CTI's job is to close the gap between theory (of which there is plenty) and practice in the cooling tower industry. Members are Fluor Products Co., Foster Wheeler Corp., Hudson Engineering Corp., Lilic-Hoffmann Cooling Towers, Inc., The Marley Co., and J. F. Pritchard & Co. of California. When it started on standards, CTI learned quickly that conventional instruments and methods
INDUSTRIAL AND ENGINEERING CHEMISTRY
did not give consistent answers in measuring cooling tower performance. Instrumentation was thus the first big problem. First step was to buy precision air and water flowmeters. Next, CTI adapted for its purpose two specially designed Air Force instruments for measuring wind velocity and direction. They're electronic, actuated by an interrupted light beam, and hold friction effects to a minimum. For wet-bulb measurement, CTI developed a replacement for the conventional sling psychrometer. It's a mechanically aspirated psychrometer whose self-contained motor blows a steady 1000 c.f.p.m. of air over the wet bulb. The wick has a constant distilled water supply in a reservoir arranged to preclude heating or cooling effects on the bulb; distilled water avoids heat of solution effects in saline conditions and assures uniformity. On performance runs, CTI spaces 12 such psychrometers around the cooling tower. Readings may not be the precise adiabatic saturation temperature, but they're very close and they're consistent. Its instruments assembled, CTI bundled them into a mobile test unit and a field (chemical) engineer set out with it to measure actual performance of cooling towers submitted by cooperating users for study. Field work started on the Gulf Coast in 1951 and covered the country this past summer. CTI analyzes the data and distributes results to its members, cooperating
W a t e r Savers. CTI's field engineer covered the country last summer with this mobile test unit, measuring performance of cooling towers under field o p e r a t i n g conditions. Instruments on tripods a r e mechanically aspirated psychrometers d e v e l o p e d b y CTI
PATTERN PROGRESS Each m o n t h l&EC w i l l s h o w h o w articles published in earlier l&EC v o l u m e s helped set future industrial patterns. This m o n t h , w e turn to 1 9 1 3 a n d to c o m m e r cial utilization of large bodies of rock k n o w n as nelsonite.
I N THE I&ECof 1913, W. H. Waggaman challenged I&EC's readers with an article "A Possible Commercial Utilization of Nelsonite." Mr. Waggaman introduced his subject with this statement: " I n Nelson County, Va., there are large bodies of rock locally known as nelsonite, which consist essentially of the two minerals ilmenite and apatite. The material is not only of scientific interest but in the light of some recent experiments performed in this laboratory, may be of considerable commercial importance." Only now is it possible to see just how accurate this prediction proved to be. Fortunately for I&EC's editors, Mr. Waggaman is still with the Bureau of Mines, and still challenges I&EC's readers (last year it was on some conservation problems of the phosphate industry). Nelsonite ore occurs in large dikelike bodies in Nelson and Amherst Counties, south central Virginia, and consists essentially of a mixture of ilmenite (titanate of iron) and fluorapatite. Ilmenite is rather widely distributed in nature, occurring in other crystalline rocks. It is frequently
associated with magnetite. Apatite or phosphate rock is a brittle crystalline mineral which varies in color from almost white to dark green-red and brown. There are two main varieties of this mineral; chlorapatite and fluorapatite, the latter being more plentiful than the former. Prior to the publication of Waggaman's article and for a time thereafter, little attention was given these deposits, though limited quantities of rutile (T1O2) were produced and marketed from this area. Waggaman's interest in commercial utilization of nelsonite was primarily in the successful extraction of the apatite ore. At the time, there was no market for the ilmenite ore. When the value of ilmenite as a raw material for the manufacture of titanium pigments was recognized, considerable interest developed in nelsonite ore, and in 1937 exploitation of these deposits was undertaken on a commercial scale by the Southern Mineral Corp., a subsidiary of the Vanadium Corp. Two methods for separating the two minerals were tried and the results reported in the original 1913
paper. The first was based on the difference in specific gravities of the minerals, and the second on the magnetic properties of the ilmenite. Separation by means of a magnetic separator was feasible but thought to be too expensive for commercial use. The method of separation proposed was one based on the differences in specific gravity. The specific gravity of apatite is 3.2 compared to 4.2 for ilmenite. This difference was considered sufficiently great to warrant a fairly clean separation, provided the rock was crushed to a uniform size. Just how satisfactory this process has proved to be can be seen by the fact that Southern Mineral Corp. used this difference in specific gravity of the two minerals to effect the separation. In addition, flotation methods were employed to make the final separation. Good quality ilmenite low in phosphorus and high grade apatite concentrates low in iron were obtained. The ilmenite was used for the manufacture of titanium pigment and for some years the apatite concentrates were sold to the Virginia Chemical Co. and employed in the manufacture of phosphoric acid and monocalcium phosphate for leavening purposes. These deposits were subsequently acquired by the American Cyanamid Co. and have been worked ever since for their ilmenite content. According to the latest reports, the apatite is being stock-piled awaiting a more favorable market for this mineral.
EEB users, and, in bulletin form, to industry at large. They've learned, for one thing, that conventional aerological data —averages for large air masses— mean nothing to a cooling tower. Microclimate, right at the tower site, is the thing. And when measured precisely, that microclimate turns out to be a violently fluctuating battle between heat and moisture. Average values for temperature, humidity, and wind direction and velocity don't tell the story. It takes simultaneous, precision measurement of all variables.
CTI learned, too, that down-wind cells in long, rectangular (plan view) cooling towers can load up—become essentially useless—under certain conditions. And performance of an average size tower becomes critical when the wind blows at about 30 degrees to its longitudinal axis. These are just brief indications of what CTI's field work has done. Still in progress, it has produced a stream of data invaluable in cooling tower design. From it also have come the cooling tower industry's first standard performance testing
specifications (CTI Bulletin ATP105 is the current revision). CTI stands ready to help users and makers of industrial water-cooling towers use these tests, and is developing a portable test kit to be available on order to those who want to check their own towers' performance. Besides performance standards, CTI has developed redwood lumber specifications and framework design data for cooling towers (Bulletin STD-103). This bulletin combines a complete description of the CTI grades of redwood lumber for use VOL. 48, NO. 12
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REPORTS in the construction of industrial water-cooling towers and the corre sponding allowable design stress values for these grades in framework design. And it has spent 5 years studying wood maintenance (Bul letin WMS-104). One result of the latter is that, to date, four chem ical preservatives seem definitely to protect redwood, fir, cedar, and pine against biological attack in cooling towers. They are: creo sote, Chemonite (J. H. Baxter & Co.), and Erdalith and Celcure (both Koppers). Because of price and availability of redwood, plus changing plant operating practices (which change the chemistry of recirculating water), we may one day see treated fir, cedar, and per haps other materials competing with redwood in cooling towers. CTI's next standards push will be on large, propeller-type fans and their speed reducer gears. Fans must move large volumes of air at low pressures and velocities, and there is little basic technology in the field. Right-angle gears must make about a 10 to 1 reduction, working in a hot, saturated, corrosive vapor. Lubrication is one of several prob lems here, but a good deal of per tinent technology exists and CTI expects to develop its standards as modifications of present industrial gear .standards.
I/EC
Paul Bunyan Chemistry Researchers are trying to find out what makes chemical debarking work
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ARK, the "fabulous waste," has now found its way into chemical markets (I&EC, January 1956, pp. 75 A—76 A). And wood chemistry, generally, is becoming more im portant (I&EC, March 1956, pp. 7A-10A). But chemical mysteries in the field still await additional detective work. Chemical debarking is a good ex ample—researchers are puzzled over the mechanism that causes arsenites
and sulfamic acid to loosen bark from trees. Chemical debarking, practiced on a commercial basis for more than 8 years, is still hardly more than an established empirical process. Pulp and paper companies in the United States annually treat more than 50,000 cords of pulpwood in this way, without really knowing why or how their process works. How It's Done
In its simplest form chemical de barking works this way: A band of bark is removed from the tree early in spring and the exposed sapwood is painted with a solution of sodium arsenite. The woodsman's tools may be simple or elaborate, but so far the only chemicals that give satisfactory results are soluble ar senic compounds. Within 10 days after a chemical application, the tree dies. It is almost impossible to peel a living tree during the period in which chemical debarking takes place (from September until the following sum mer). (Six months or a year later, bark may be peeled from the tree with minimum effort.) Although not much is known about the process, chemical debarking has one big advantage: It extends the time of easy peeling from a 2-month period in the spring to almost a year-round basis. Almost all trees commonly used for pulpwood respond to this treat ment. (Ash is an exception, as results are erratic and only occa sionally will this species peel well.) But other natural conditions pro hibit chemical debarking of certain tree species. For example, decay and insect attack are unusually severe after treatment of white pine in the
I/EC
North and pulpwood trees in the South. Cost of treatment will vary with the volume of pulpwood handled and tree diameter. Most foresters say it is economical to work with a large volume of trees bigger than 10 inches in diameter. On this basis, one would expect to consume an average of 0.05 gallon of sodium arsenite and 0.6 man-hour per cord. This year foresters in the United States will probably use 10,000 gallons of 40% sodium arsenite solution; their Canadian brothers about 4000 gallons. Where We Stand
At New York State University, foresters recently completed a 4-, year cooperative project, trying to learn the whys and wherefores of chemical debarking. They not only found out a great deal about funda mental physiological aspects of the process; researchers developed some improved application techniques. In the past other researchers have tested hundreds of chemicals, hoping to find a compound which is nontoxic to animals. But they couldn't turn up a suitable substitute for sodium arsenite. The Syracuse group, in looking at organic arsenicals (such as monoethanolamine arsenite), found a few compounds that may actually be more effective than sodium arsenite. Because of their odor and probable lack of "saltiness," these compounds might be less attractive to wildlife. When the door opens to this new possibility, more research can be expected in this field, with the hope of providing protection to forest wildlife. H.W.H.
ΟΕΕΞ VOL. 48, NO. 12
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