TECHNOLOGY
Tall Oil Fractionator Capacity Tripled Change in reflux ratio, close control of variables give more product with no new equipment Sharp engineering by Union BagCamp Paper has tripled output of refined products from tall oil without adding any equipment. How? By lowering reflux ratio during fractionation, plus close control of process conditions. And Union-Camp gets an extra bonus from its engineering: Product from the modified process, it says, is better than product from the process as designed. Consumption of tall oil products has been increasing rapidly over the past few years. To keep pace, refiners have turned to the fractionation process rather than acid refining, the earlier route. In fact, only National Southern Products now uses acid refining exclusively, and Union-Camp runs the only other commercial acid refining unit now operating. Union-Camp's fractionation plant went on stream in 1956 with a design capacity of 15,000 tons per year of high purity rosin, fatty acid intermediates, saturated fatty acids, and distilled tall oil. It uses a "blocked" process. Some of the equipment does two jobs; one feed stream is blocked off while the other is being used.
Demand soon exceeded the plant's 15,000-ton capacity, so the company decided to expand. Since the blocked operation worked so well, UnionCamp didn't want to convert to a continuous process, which would be less flexible, the company feels. And the second fractionation column would cost more than alternative methods. The blocked process, designed and built by Foster Wheeler, was designed from conventional techniques for such fractionations, Union-Camp points out. Reflux ratio in the bubble cap fractionator was high, and the column had the usual safety factors engineered into it. Crux of the increase in capacity, says Ellis O. Barnes, chemical products division's manager of manufacturing and research, was to lower the reflux ratio and then control process variables more closely to keep the column from flooding. The company did this by Lipping the steam rate—the fractionation uses sparge steam—and decreasing the rate of condensate return. This moves the operation much closer to the limiting vapor velocity (at which the column would flood), removes more product
Blocked Tall Oit Process Has These Steps Crude tall oil is flash distilled continuously in small stripping tower to give pitch (bottoms) and purified tall o i l Purified tall oil flows continuously into fractionator where high grade rosin (bot· toms) is separated from fatty acid intermediates. The latter go to hold tanks. Fatty acid intermediates from storage are processed batchwise through the same fractionator, yielding bottoms of distilled tall oil, tops of saturated fatty acids, and a middle cut of unsaturated fatty acids (principal product).
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TALL OIL TOWER. More steam, less condensate return in Union-Camp's fractionator at Savannah, Ga.f tripled output
per unit of heat, and actually lowers operating temperature. The modifications work very well, Mr. Barnes says. And control of the variables—steam rate, operating temperature, and column pressure—keeps
fractionator performance satisfactory. The equipment now processes close
Fractionator
Odor Cut Stripping Tower
Purified
Reflux Circuit Fatty Acid Intermediate
Tall OH
Pitch Rosin
To storage for another run through fractionator for final separation
TYPICAL COMPOSITION OF TALL OIL FATTY ACIDS Oleic acid Linoleic acid Conjugated linoleic acid Palmitic acid (A)
51% 37% 10% 2%
(A) Includes small amounts of other saturated acid: stearic, lignoceric, cerotic»
to 50,000 tons of whole tall oil a year. And because the heat-sensitive main products (fatty acids) stay in the column for less time, they come out almost water-white. Union-Camp plans to stick to the blocked process when it has to expand again. Reason: A continuous process must run relatively inflexibly to be efficient, while multiple blocked units can be operated independently to give better control over inventory additions when shipments become irregular.
Chemical Grouting Progresses American Cyanamid has decided to turn over the marketing of its chemical grout, AM-9, to a commercial division of the company. The move may be made by the end of this year. So far, the product has been in the hands of the firm's commercial development de partment, but now Cyanamid has done enough field development work to warrant placing AM-9 in its product family. AM-9's initial use lies in soil stabil ization, particularly in the mining and construction industries to prevent water seepage. It is a water solu-
ble mixture of acrylamide and Ν,Ν-methylene-bis-acrylamide. When mixed with catalysts, ammonium persulfate and /?-dimethylaminopropionitrile, it will polymerize into a gel. The catalyst and AM-9 are mixed at the job site and either injected or per colated through the soil, sand, or loose rock. The polymer formed is crosslinked, and there is some bonding to the mass particles. Gelling time can be controlled to give immediate gelation or to delay it up to 24 hours. The chemical is ap plied to the soil with positive displace ment pumps which handle the AM-9 and catalyst solutions separately. The two solutions are brought together and mixed at or near the injection point. Cyanamid says that AM-9 has been tested in over 150 field applications. It has been used to seal off the flow of underground water into oil wells, drill holes, tunnels, mine shafts, and open excavations. AM-9 can also be mixed with cement, Bentonite, sawdust, dyes, salts, and thickening agents to modify the resulting gels. AM-9 is another product stemming from Cyanamid's long-time interest in acrylamide. It has been under devel opment for seven years and is an out growth of the U.S. Army Corps of En gineers' interest in a chemical spray that could turn sand or earth into a hard airstrip in a few hours. Some work was done at the Massachusetts Institute of Technology and then at Cyanamid's Stamford, Conn., labs. Field trials began in 1954, and now Cyanamid is making the grout at its Warners (Linden), N.J., plant. AM-9 is available at 85 cents a pound, f.o.b. Warners. Cyanamid also supplies the catalysts.
New Radiation Symbol
R = Radius of central disk
The American Standards Association has adopted this symbol to "signify the actual or potential presence of ionizing radiation and to identify objects, devices, materials or combinations of materials which emit ionizing radiation." Ionizing radiation (for the purpose of this standard) includes y and x-rays, « and β particles, high speed electrons, neutrons, protons, and other nuclear particles. It does not include sound or radio waves, nor visible, 1R, or UV light—and does not specify the radi ation levels at which the symbol is to be used, ASA says.
code names confusing you ? Would you prefer to relate surfactant
performance
to chemical composition ?
OLYGLYCOL STERS provide the chemist with the opportunity to investi gate the effect of Stepwise V a r i a t i o n s in Surfactant Composition on emulsification, wetting or other surface - active application. This extensive series of sur factants includes O l e a t e , Stéarate and Laurate esters of Polyethylene Glycols, ranging in molecular weight from 2 0 0 to 6 0 0 0 . Our Technical Service Laboratory welcomes the opportunity to assist you in the application of these products
KESSLER CHEMICAL CO., Inc. 7294 State Road, Philadelphia 35, Pa.
ESTERS FOR INDUSTRY,
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BRIEFS
impossible?
Certificates of safety achievement for an accident-free 1959 have been awarded to 475 plants from 49 member companies by the Manufacturing Chemists' Association. Of the 475 plants, 19 have had no accidents for the past 10 years, 15 for nine of the past 10 years, and 186 for three or more of the past 10 years. The 1959 injury frequency rate for MCA members was 3.38, up 13% from 1958's all time low of 2.98. Severity rate was 617 man-days lost per million man-hours worked, up 18% from 1958. The frequency rate increase was limited to isolated segments of the industry, MCA says. Samarium-153, a low energy radioisotope, dissolved in hydrochloric acid can measure small variations in wall thickness of complex shapes of nickel alloys, according to studies by General Motors. Dr. William J. Mayer, Walter H. Lange, and William L. Shelly of GM have used the technique to check the vanes and blades of an experimental Allison turboprop engine, say that it can probably be extended to other types of. small hollow extrusions or castings whose design intricacies make conventional gaging impossible. Seven U.S. and Canadian patents on pulp and paper technology are being offered to the industry on a royaltyfree basis by Hooker Chemical. The patents cover chlorine dioxide production, calcium hypochlorite production, sodium sulfate and hydrochloric acid recovery, a three-step bleaching process, and purification of kraft and other pulps. Chemical milling as a technique to mass produce electronic components will be studied by Chemical Milling International, El Segundo, Calif., under a research and development contract from International Business Machines. CM I will do the work at its El Segundo plant.
Impossible . . . no. Difficult. . . yes. Any problem looks that way before it's solved. That's where the challenge lies . . . and that's where Kay-Fries can help with a classical series of low molecular weight aliphatic polyf unctional molecules.* Technical literature, samples and advice are yours for the asking. M * V . · FIUC
KAY-FRIES CHEMICALS, INC., 130 MADISON AVE., N. Y.C. *Barbituric Acid · Cyanoacetic Acid · Cyanoùcetamide · Methyl and Ethyl Cyanoacetate · Ma* Ionic Acid · Diethyl Malonate · Dichloroacefic Acid · Methyl Dichloroacefate · Malonaldehyde Diacefal · Malononitrile · Methyl Chloroacetate · Methyl and Ethyl Orthoformate.
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Mockup tests of Kiwi-Α Prime, AECNASA's experimental nuclear reactor for rocket propulsion studies, are un der way at AEC's Nevada test site. The tests are cold flow checks of the instruments, sensors, and hydrogen propellant system which will be used in static tests of the actual reactor this summer. The mockup contains no radioactive materials.
