THE CHEMICAL WORLD THIS WEEK
POWER PLANTS:
MHD Cheaper, Cleaner M agne tohy drodynamics (MHD) shows promise of improving efficiency, lowering fuel costs, and alleviating thermal pollution in future central station power plants using fossil fuels. So concludes a report issued last week by a special panel of utility executives, scientists, and engineers set up by the Office of Science and Technology to study the current status of the powergenerating technique. The promise is such that the panel calls for government funding of about $2 million per year for research and development. It hopes an equal amount will be forthcoming from the utility industry and suppliers. Work on a complete coal-fired M H D demon stration plant should await results from the R&D, which the panel expects will take three years or more. Carrying out the recommendations of the panel would revitalize an area of development that saw a flurry of industrial activity in the late fifties and early sixties but which has since grown dormant—primarily, d i e panel notes, because of uncertainty over the bene-
fits and the need for industrial com panies to decide among competing schemes. MHD, in its most developed form, uses an open cycle in which the work ing fluid is seeded gaseous combustion products. Hot gas from combustion is seeded with an easily ionized ele ment (such as cesium or potassium) to increase electrical conductivity and sent through a nozzle. A magnet surrounding the nozzle induces elec tricity in the flowing gas. The elec tricity is withdrawn by electrodes and the gas sent to an air preheater and steam generator. Plants using this concept, the panel says, should be able to achieve over all efficiencies ranging from 50 to 607c By comparison, the best fossil fueled plants reach 40% and cur rent nuclear-powered ones only 3 3 % . The panel notes that controlled ther monuclear fusion promises to open a completely new energy source, and breeder reactors would greatly extend nuclear fuel reserves. M H D , on the other hand, would initially extend con ventional fossil fuel reserves. It ap pears, the panel says, that magnetohydrodynamics would bring about a saving in fossil fuel of about one third.
MHD: Panel Recommends More R&D Seed Preheated air
Ρ Coal
Air DC * *» i* AC
Water
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Air compressor
PEOPLE:
NSF Gets McElroy President Nixon has named Dr. William D. McElroy, chairman of the department of biology at Johns Hopkins University, to be the next di rector of the National Science Founda tion. Dr. McElroy succeeds Dr. Leland J. Haworth, whose six-year term has expired. Dr. McElroy's appointment follows by a few weeks a shock wave of pro test from many scientific leaders when the President blocked the appointment of Dr. Franklin A. Long of Cornell 10 C&EN JUNE 30, 1969
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to the director's job because of Dr. Long's opposition to deployment of an ABM system. Vigorous protests— to the effect that NSF should be kept out of politics—prompted the President to reverse his position and offer the job to Dr. Long (C&EN, May 5, page 9 ). But Dr. Long declined the offer. Dr. McElroy avoids the ABM issue by not taking a public stand on it. Dr. McElroy's appointment has re ceived plaudits from the leaders of the scientific community. NSF direc tor Haworth says that Dr. McElroy "will bring to the foundation a great wealth of experience and wisdom . . .
William D. McElroy Biologist heads NSF
in both the academic and government science communities. I am confident that he will be an outstanding director. Dr. Philip Handler, chairman of the National Science Board, agrees. He says "the National Science Board is extremely pleased" at the appoint ment. Dr. McElroy's research interests in clude the mechanism by which chem ical energy is changed into light en ergy by living organisms such as fire flies, luminous bacteria, and marine organisms. In examining this process he has unraveled the structure of luciferin, and the role of oxygen. Dr. McElroy, 52, earned his B.A. (1939) at Stanford, his M.A. (1941) at Reed College, and his Ph.D. in biol ogy (1943) at Princeton. H e has been chairman of the Johns Hopkins biology department since 1956. Dr. McElroy is director of the M o Collum-Pratt Institute at Johns Hop kins. He has been a member of various NSF advisory bodies and the President's Science Advisory Commit tee. He is a member of the Na tional Academy of Sciences, American Association for the Advancement of Science, American Chemical Society, and Society of Biological Chemists.
ABRASIVES:
GE's Cubic Boron Nitride Grinding of hardened steels will be faster and less expensive with its new Type II boron nitride abrasive, says General Electric. Next in hardness to diamond, cubic boron nitride is su perior to aluminum oxide and other
abrasives for many metalworking uses. The material is nickel coated. Development of cubic boron nitride, which in the new form is trademarked Borazon by GE, is a followup to the company's work in synthetic diamonds. Evaluation quantities—25 to 2500 grams at $12 per gram for Type II Borazon—are now available from GE's Specialty Materials Department, Worthington, Ohio. Borazon, from boron and "azo" referring to nitrogen, is physically similar to diamond. Its hardness is 4700 on the Knoop scale and 18.5 on the Mohs Woodell scale, more than twice as high as aluminum oxide. Its structure is that of interlocking and alternating atoms of boron and nitrogen. Cubic boron nitride has better resistance to oxidation than does diamond, GE says. Diamond, which is carbon, burns in air at about 1600° F., whereas cubic boron nitride can withstand temperatures of 2500° F. At about 1800° F., the crystal surface oxidizes to form a thin layer of boron oxide, which prevents further oxidation if the layer remains intact until temperatures of 2550° F. are reached. At this temperature, conversion to hexagonal boron nitride begins. Cubic boron nitride, not found in nature, is made from hexagonal form, a soft white slippery material similar in physical characteristics to graphite. The hexagonal form is converted to the cubic form by using pressures of about 1 million p.s.i. and temperatures above 3000° F., with equipment basically similar to that used to make synthetic diamonds, GE says. The Borazon Type II cubic boron nitride is coated with nickel to minimize friability of the crystal. The nickel coating melts off at about 1300° F. Preliminary laboratory and field testing shows Borazon to be better than both aluminum oxide and diamond in wet and dry grinding of hardened "M" and "T" series of tool Cubic boron Next in hardness to diamond
steels, says GE. Time and cost savings are between. 20 and 70% depending on the metal and the shape ground. Other cost savings over aluminum oxide are indicated by the lower surface temperature of a workpiece when ground with the new abrasive and by reduced metallurgical surface damage.
AUTOMATION:
Hints from OCAW "In America today, we have an excess of efficiency and a deficit in comfortable human relations. Our current need is not so much to manufacture more products as to create more consumers and put to more enjoyable use the wealth we have created." The impact of automation on the oil and petrochemical industries thus was viewed by A. F. Grospiron, president of the 180,000-member Oil, Chemical and Atomic Workers International Union. Labor and management need more, not less, collective bargaining in automated industries, he told a Houston, Tex., meeting of the Petro Group of the South Texas Section of the American Institute of Chemical Engineers. Automation is inevitable, and it likely will be beneficial in the long run. But automation must be applied with judgment, common sense, and recognition of the human factor, he emphasized. Recognition of the human factor is not necessarily artificial retention of employees no longer needed. It more often requires only careful rescheduling and retraining of employees. More important, it requires making changes in concert with the employees, rather than changing employment by unilateral management fiat, he said. Provisions for limited job guarantees negotiated by OCAW some 28 to 30 months ago clearly have resulted in a great reduction in layoffs. The provisions call for a 60-day advance notice for layoffs of present regular and permanent employees and consultation with the union on means of avoiding or easing layoffs with the right to strike after 60 days. Mr. Grospiron went on to hint at subjects which might be key points in negotiations when many current contracts between OCAW locals and various companies run out at the end of 1970. One point for possible negotiation could be discussions on effects of installation of new, more automatic equipment and processes a year or more in advance. Another point of concern may be about the growing number of personnel who have responsibility to supervise operation of equipment, but who do not have authority over workers.
PAVING:
Market for Styrene A freight train hauling 36 boxcars full of Dow Chemical's Styrofoam rolled into Seattle last week. The consignment, shipped from Dow's plant in Torrance, Calif., is now being readied for a 2500-mile trip by barge. Destination: Kotzebue, Alaska. There, the state's division of aviation will use the 1.4 million board feet of the extruded plastic foam in the construction of an aircraft runway. Another 500,000 board feet are going in at Anchorage International Airport. "The Alaskan shipments represent the largest single order for Styrofoam we have received to date," notes Dow's Jack Jones. This development could open up an enormous outlet for styrene. Dow, which makes Styrofoam by a patented process that involves extrusion and stretching of polystyrene, has been looking into the use of the product as an insulating bed in highway building for a number of years. Now the idea is catching on. Before summer is through upward to 2 million board feet will likely be used in roadways in Pennsylvania and Wisconsin. The rigid boards of polystyrene foam are incorporated into the subbase portion of the pavement. By acting as insulation, the foam protects the surface from dimensional changes brought about by thawing of ice pockets ( or ice lenses ) in the subgrade during the summer months. At Kotzebue, which lies inside the Arctic Circle on Alaska's west coast, the 6000-foot runway must be able to withstand the weight of large commercial jets that serve the area in increasing numbers. "The asphalt runway will trap and concentrate the sun's heat during the long summer days. This, coupled with the fact that the vegetation, which acts as an insulator, is being stripped from the surface, increases the chances of the ice lenses within the underlying permafrost becoming thawed," explains Clayton Hueners, chief design engineer with Alaska's division of aviation. The resulting pockets of soft earth won't be able to bear up under the weight of the aircraft. Though admittedly Styrofoam HI doesn't come cheap—price ranges from about 12.5 to 14 cents per board foot depending on the size of the order—its use can make a sizable difference in labor costs, points out Dow's Fred Giachino. To avoid frost humps, for example, it's often necessary to replace as much as 6 to 8 feet of frost-susceptible topsoil, he notes. "Using polystyrene, you need only clear down to a depth of about 18 inches," he adds. JUNE 30, 1969 C&EN
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