THE CHEMICAL WORLD THIS WEEK C&EN REPORTS:
2 3 r d Exposition of C h e m i c a l
Industries
European Equipment Stars at Chemical Exposition Sizes, applications, r a n g e s b r o a d e n f o r heat trans fer e q u i p m e n t NEW YORK.—Perhaps the one outstand ing feature of the 23rd Exposition of Chemical Industries, held in New York's Grand Central Palace last week, was evi dence of the renaissance of European manufacturers. Not for a number of years have visitors been faced with so many items of European origin, either as direct imports or as items manufactured in this country and based on European design. Both England and Germany are bidding heavily for our dollars—England with a Delanium-cored heat exchanger, and a dry materials mixer, Germany with the Luwesta centrifugal extractor—items of considerable interest t o engineers at the show. Nearly 4 6 0 exhibitors showed their products to the 5000 spectators which crowded the four floors of Grand Central Palace from Nov. 26 to Dec. 1. Not that American manufacturers were left at the post, however, as the following descriptions of their entries will attest. But the European imports put up a good battle for the blue ribbon. Goal of Continuous Mixing Beckons Continuous operation is the stuff engi neers' dreams are made of. Mixers and kneaders are still heavily centered on batch operation, mainly because of the difficulty of securing a homogeneous mix in processings requiring the incorporation of small amounts of ingredients. But while batc'i operation was the predomi nant feature of the machines of this type displayed this year, continuous operation is the beckoning goal. Baker Perkins introduced a new continu ous mixer-kneader in this country for the first time this month. Developed in Switzerland about seven years ago and based on the "List" system, t h e new mixer assures a uniformly mixed product con tinuously, whether the ingredients be in nearly equal proportions or include some of the 1% magnitude, the company re ports. Novel design feature accomplishing this uniformity is the two-steps-forwardone-step-backwards progress the ingre dients make as they move through the mix ing trough from hopper and discharge. The machine is adaptable to a complete range of materials from light solids to viscous pastes. A worm blade which 5234
opening of a natural funnel when the chamber is rotated to a point where the opening is at the bottom. All corners and edges inside the box have large radii, eliminating those hard-to-clean crevices. Units range from 0.17 to 2 5 cubic feet in charging capacity. Chase reports that these charging capacities are based o n 4 0 % of the total volume, but adds that in the case of particularly free-flowing ma terials this figure may be upped to 6 0 % .
Alkali-Resistant Glass-Lined Kettles both reciprocates and rotates furnishes the An undisclosed variation of borosilicate propelling force intervals that correspond to the kneading teeth mounted around the glass composition has been developed that trough. The horizontal and rotary motions has sufficient alkali resistance to be service are so coordinated that the gaps meet and able in boiling alkali up to a pH of 12. A maximum pH of 9 at boiling was rec pass the kneading teeui as the blade re volves. As each portion of the blade ommended for the previous composition. passes a tooth, part of the material is Acid resistance of the new lining equals carried forward, part is left behind for that of the older composition. The n e w lining material, only recently further mixing. W i t h small amounts of in gredients, it is possible to add them por- announced by Pfaudler Co., has been tionwise as much as 30 seconds apart at service tested for about a year in actual the hopper and still have a homogeneous large-scale industrial operations. One sig nificant asset of the extended range is that mix, according to Baker Perkins. Another import from abroad is a batch a single kettle can now be used for the mixer for pharmaceuticals and related ma neutralization step and some other process terials, which is produced by Foster Yates ing operations where the p H change in & Thorn, Ltd., and marketed and serv volved previously required use of a second iced in this country by Chase Equipment unit to avoid excessive corrosion or prod Corp. It was introduced to show visitors uct contamination. The company states this year. Units consist of a cubical mix that spalling tendencies and other physical ing chamber mounted on a horizontal properties are at least as favorable as for shaft that supports the chamber at nearly the older lining composition. Coating d e opposite corners. T h e chamber contains fects requiring plugging with tantalum or four X-mounted paddles which rotate in other resistant materials are claimed to the box in the same direction as the box. occur less frequently than with the previ (Paddles rotate at a ratio of 3 r.p.m. to ous material. The new lining comes in the 1 r.p.m. for the box; they move in the familiar blue color or, at slight extra cost, in light gray. The latter color is said to b e same direction to minimize dusting.) more efficient for photochemical reactions Chase reports that such a combination of rotating cube and paddles eliminates deadΕ. Μ. Schmiel, company representative, spots and helps to assure intimate intergives consideration to questions by Fred folding of ingredients, even though they Adams, left, about new continuous mixerkneader exhibited by Baker Perkins, Inc. may vary widely in specific gravity, parti cle size, and ratio. Liquids may, of course, be part of the ingredients, provided the final mix is essentially a dry one. Of interest to processors who must have thorough cleaning between runs is the ease with which the chamber may be dis charged and cleaned. T h e main lid is one entire side, and it may be removed by loosening a few bolts. It also has a quickopening circular lid in one corner. In addition, there is a small flap-closed open ing in one corner, which serves as the
The Week's Events Steacie Asks for Better Methods of Determining Bond Dissocia tion Energy Chemical Industry's Expansion Plans Top Everything But Steel Klare S. Markley Receives Fourth Southwest Award
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and appears to permit better inspection of the kettle contents and any residues re maining after clean-up. Pfaudler also features a line of flexible Standard shell-and-tube heat exchangers fabricated from stock components. Fourto 12-week delivery on units up to 10inch diameter is one advantage of the modular approach in fabrication.
I&EC Reports section of November 1951 Industrial and EngineeringChemistry. N e w Components in Twin-Shell Blender Patterson-Kelley is showing new features of their twin-shell blender line. Loading is now made easy by a tilting hopper dis charging to an axial screw leading to the blender interior, and discharge can b e facilitated with an electrically operated discharge valve. As a second feature, an axially rotated breaker rod, called an in tensifier, can be provided. The intensifier is easily removed and is particularly useful when small amounts of liquids are added that form soft lumps until well dispersed throughout the charge.
Cubic Heat Exchanger in Graphite A compact heat exchanger design, first commercialized in Great Britain, made its physical debut on this side of the Atlantic through the British-American Carbon Corp., a company created six months ago and jointly owned by Great Lakes Carbon and the British firm of Powell Duffryn. Werner Habig, Peter Stahl, and Peter Steinacker of Centrico, Inc., discuss the Luwesta countercurrent solvent extractor shown at their exhibit
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industries with the first U. S. showing of the Luwesta countercurrent solvent extrac tor manufactured by the Westfalia Sepa rator Co. of Germany. On exhibit is the largest standard model, a three-stage unit with 500- to 1000-gallon-per-hour capac ity. Centrico was formed within the past two years and is the sole U. S. distributor for Westfalia's line of centrifugal sepa rators, clarifiers, and purifiers. A technical description of the operating performance o f the Luwesta extractor appeared in the
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At the Nichols Engineering search Corp. booth, a spray dryer featured in equipment manufactured in
and Re portable line of Denmark
Physical and thermal properties of the I Delanium graphite core can be controlled over a wide range by heat treatment during manufacture. Header arrangements permit up to 16 passes, and the permissible corrosiveness of both heat exchanger fluids is limited only by the relatively inert graphite. Other advantages are rugged and simple design and small floor space needs per square foot of exchange surface. The smallest unit, having a nine-inch graphite cube as its core, has a heat transfer area of 10 square feet and a coefficient of 300 to 500 B.tai. per hour pei square foot per 1 ° F. when heating water to steam within the velocity range of one to six feet per second. On exhibit is the large standard unit containing a 15-inch cubical element with 5 0 square feet of exchange surface, which requires cubic space of two feet in each dimension when headers are attached. A more extended report of the graphite and the exchange design appeared in the February 1951 issue of Industrial and Engineen.ig Chemistry (page 7 A ) before the unie had an agent in this country.
Chemical Equipment in Polyester-Reinforced Class Fiber Another material of construction is now available for chemical processing opera tions with the introduction late this year of Chemical Corp.'s line. Essentially the same material and construction used in the beetle Fiberglas boats, the know-how of these two companies were combined in the development. High physical strength, chemical inertness, and resistance to tem peratures υρ to 250° F. are the principal advantages noted for the material, along with ease in field fabrication and repair. The line is available in pipe and duct of six-inch diameter and greater, and in spe cially fabricated vessels and vessel linings. The six-inch pipe, which weighs less
Use CARBIDE'S Esters . . . . i n Your Lacquer The high purity and uniformity of CARBIDE'S ester sol vents will help you maintain high standards of quality in the manufacture of lacquers. Β. P*°C CELLOSOIVÉ Acetate
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Methyl Amy! Acetate
146.3
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Butyl Acetate i$ the , standard boiling
medium-*
lacquer
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resistance { 8 3 % ret humidity at δΟ^Ρ*}**,
Iz- Isopropyl Acetate I
Bbyl Acetate
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toluene dilution ratio
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l· "Cellosolve" is a registered trade-mark of Unfon Carbide and Carbon Corporation.
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Luwesta Extractor Makes U. S. Debut Centrico, Inc., is attracting considerable interest from pharmaceutical and other V O L U M E
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NO.
50
» DECEMBER
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10,
1951
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W I H I H H H ^ iHInjjS^ ^MLtH{»^()() pounds. Flat sheets are also available that can be cut and bonded in the field to the desired shapes. A rectangular fume duct section is being demonstrated that was field constructed. Development of the new line was started early this year originally for the β electroplating industry. The broad market in chemicals caused the company to ex tend its line recently. Chemical Corp. was a victim of the exhibition space sell out success of the Exposition, and showed its products in a suite at the Shelton Hotel.
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Pilot tests and preliminary field reports indicate their usefulness in scores of w a y s — t o m e n t i o n a few, a s catalysts, intermediates and plasticizers and as a g e n t s for sizing, thickening, wetting, dispersing, o x i d i z i n g , deodorizing, etc. All are backed by Wyandotte's sixty years of experience in the manufacture of c h e m i c a l s of quality i n quantity. For full details about any of these or ganic chemicals, write Wyandotte Development Department.
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SOME OF THE ORGANIC CHEMICALS RECENTLY DEVELOPED BY WYANDOTTE Carhose (Sodium Carboxymethylcellulose) Carbose I Carbose IM Carbose LS Pluronics (Nonionic Surface Active Agents including the first 100% active Flake) Pluronic L44 Pluronic L62 Pluronic L64 Pluronic F68 Sadiu m. Hydroxyalkanesulfount es Sodium 2-Hydroxyethanesulfonate Sodium 2-Hydroxy-l-pro panes ulf onate Benzene sulfonamide Derivfitives N. !N-Di-n-Buty] Benzenesulfonamide N. N-Dicarboxyethyl Benzenesul· fon amide >». VDicyanoethyl Benzenesul fonamide IS'-Kthyl Benzenesulfonamide N-Isopropyl Benzenesulfonamide N-/i-Butyl Benzenesulfonamide
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WYANDOTTE CHEMICALS CORPORATION · WYANDOTTE. MICHIGAN
VOLUME
2 9, N O .
50
DECEMBER
10,
1951
Chlorarnines Chloramine Β Dichloramine Β Arylsulfonic Acids Benzene^ulfonic Acid, technical Toluenesulfonic Acid, technical Xylenesulfonic Acid, refined Xylenesulfonic Acid, technical p-Cymenesulfonic Acid, technical Arylsulfonic Acid Esters Methyl Benzenesulfonate Ethyl Benzenesulfonate π-Propyl Benzenesulfonate /i-Butyl Benzenesulfonate Diethylene Glycol Dibenzenesulfonate Polyethylene Glycol (200) Dibenzenesulfonate /7-Hexyl p-Toluenesulfonate 5237
THE CHEMICAL WORLD THIS WEEK
"This lever controls the four-way valve, heart of the Hydrex pump," says G. W . Eldridge of Manton-Gaulin Mfg. «Co. to J. L . Petty and K. R. Nichols, l>oth of General Aniline and Film Corp. it may be used to move food products, such as whole cherries, without injury to the product. Biologically inert resins are being utilized in other types of pumping equipment. The E C O process pumps displayed at t h e show now have Teflon impellers, a Teflon stuffed packing box, a choice of this resin or Graphitar self-lubricating bearings. The pump casings and shafts are stainless steel. Standardization and universal application are stressed by the manufacturer, and compactness makes them suitable for small volume process work, in the laboratory, and in the pilot pLant. Chemical Pump and Equipment displayed the John Bean power pumps for extremely high pressure applications. Some of these handle 1.0 to 49 gallons per minute at pressures of 100 t o 6O00 pounds per square inch, other for pumping slurries, abrasives, and difBcudt solutions; they operate at 7 6 gallons r>er minute and 6 0 0 pounds per square inch and are made by Food Machinery and Chemical Corp. There were many plastic pumps shown this year at the exposition. One fcy Mission Mfg. Co. is m a d e of solid modified phenolic resin, cold cast, and is suitable for operation up t o 3 5 0 ° F. Lawrence Machine and Pump exhibited pumps in Painless steel for handling acid solutions, for liqaids at high temperatures and pressures, and a four-inch lined pximp for abrasive slurries. Materials used in their construction are resistant to corrosion and abrasion. W e l d i n g scale from piping systems leading to costly repairs is overcome b y a new scale-free coupling b y T u b e Turns. Making possible the erection of chemical piping free from damaging scales, it is a welding coupling of t w o forged halves, the tongue of one half slipping into the groove of the other half. Construction
5238
prevents burn-through or the formation of icicles in t h e interior. The n e w coupling is designed for certain chemical products, gases, hydraulic fluids, steam, air, and oils. Filters of n e w design this year stressed the use of corrosion-resistant materials, compactness, rapid cleaning, and simplicity of design. Niagara Filter displayed a number of these units for the chemical, food, fermentation, and process industries with capacities running anywhere from 15 t o 20,000 gallons per minute. One style featured all-metal leaves, consisting of three layers of wire screen, two of them fine, and a center piece of coarse mesh. Motors, vibrators, presses, hoists, drives, and other types of machinery are the unheralded and often unrecognized backbone of many portions of the chemical and chemical process industries. It is only at exhibitions such as these that new equipment, improved units, and old standbys can be seen in their proper perspective. Electric motors, for example, operate day in and day out without attention. Maintenance is simple and repairs infrequent. Attainment of this goal has not been easy for manufacturers but they are not resting o n their laurels. T h e newest developments they are bringing forth in this field are variable or adjustable speed motors. Reliance Electric and Engineering has centered its attention on developing electronic type controls for these motors. U. S. Electrical Motors has utilized a mechanical principle to accomplish the same objective, an easily controlled method of varying pulley diameters. In addition to these new developments, research is continuing on ways to improve the explosionproof, dustproof, and waterproof characteristics of motors. The General Electric Co., Allis-Chalmers, and Westinghouse, for example, showed motors, controls, circuit breakers, and related equipment for use in chemical plants where moisture, dust, and corrosive fumes and liquids are present. Arrow-Hart and Hegeman Electric exhibited a wide range of explosionproof and weatherproof motor starters. Another type of machinery which is widely used in the chemical industry is vibrators. A wide variety of this type of equipment was on exhibit. Allis-Chalmers showed a gyratory sifter, B. F. Gump has a rotary one, while Tyler showed various types of scr* rnr and sieves for use with sifting devices.
controlling odor, fumes, and dust associated with the paint, varnish, and printing ink industries. Due to the many problems involved in the varnish industry, these spokesmen feel that a method for controlling this dust is a big step forward. The Dracco Corp. attempted, in its exhibit, to illustrate in a cutaway apparatus the course of dust particles as they pass through bag-type dust control units. In this method the dusty air enters the bag and is filtered. After operating for a given time, the air flow is reversed to help remove the dust from the bag. This cleaning action is aided by a device which shakes the bag, dropping the dust into a hopper. The reverse air mechanism then cuts off, and the cycle is repeated. Pulverizing Machinery uses a wool felt cylinder and a reverse jet cleaning ring foi dust control. This company emphasizes the value of recovering valuable products from dust. Prater Pulverizer featured a wet method of recovering dust which is designed to cope with dusts which are not eflFectively suppressed by most wet or dry methods. Industrial Products Engineering also featured a wet wash collector scheme in addition to its dry (cyclone and bag types) methods. The wet wash method, which is frequently used for fume control, was featured by Maurice A. Knight for suppressing oil and acid mists. Closely related to the question of dust and fume control is air conditioning and humidity control. Niagara Blower had an extensive exhibit of air conditioning equipment including apparatus showing their new method of compressed air aftercooling. Other equipment is used for cold room conditioning and for controlled humidity. Another essential need for most industrial facilities is an adequate supply of water. Pfaudler's water distillation units Phillips Petroleum Co. was awarded the 19th annual Chemical Engineering Achievement Award for its cold rubber process and successful production of high abrasion carbon blacks, at a banquet held on Wednesday evening during the exposition. K. S. Adams, chairman of the board of Phillips accepted the plaque from Alfred White, University of Michigan. S. D . Kirkpatrick, editor of Chemical Engineering, watched
Growing Interest Noted in Dust and Fume Control The large number of displays of industrial equipment to control dust and fumes is indicative of a growing concern over the problems of air pollution. T h e chemical process industries now have at their command a w i d e range of all types of equipment to answer their problems in this area. Representatives of Claude B. Schneible pointed out that their multiwash collector system has been applied successfully to
CHEMICAL
***?$&& AND
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Season's Greetings from TEA/A/BSSBE
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PRODUCERS OF: FUELS · METALLURGICAL PRODUCTS · UCTS · AROMATIC CHEMICALS · WOOD CHEMICALS · VOLUME
2 9, N O . 5 0
» DECEMBER
10,
1951
TENSULATE B U I L D I N G P R O D AGRICULTURAL CHEMICALS 5239
THE CHEMICAL WORLD THIS WEEK
F. H. Jaeger of Mine Safety Appliances tells A. C Owen of Kaye and McDonald all about chemically resistant clothing made of dynel. Safely dressed man· feature acid and alkali resisting glass linings. The company points out that in many cases the need to reduce stream pollution is forcing many companies to treat
nikin looks on interestedly. This four-inch miniature recorder will save panel space, A . F . Sommer of Minneapolis-Honeywell tells Paul Kempel o f Alcoa
waste waters. By use o f proper equipment waste water may be treated not only to yield clear water but t o yield valuable byproducts.
Process Controls Go Miniature to Save Panel Space The increase in complex processes with a high degree of instrumentation has put a special premium on control panel space. The panels and the control rooms that house them are expensive and human engineers have found that one operator can give effective attention to only a limited area of instruments and control switches. One popular expedient to beat the human limitations has been the trend to flowsheet control panels. However, such panels also require very compact instruments. The instrument manufacturers have risen to this challenge and many of the results of their efforts were on display at the exposition. A definite trend toward miniaturization is apparent. The old, large electronic tubes are giving way to miniature tubes and subminiature tubes. Prefabricated compound assemblies, some using printed circuits, are helping to cut down instrument size. Complete amplifiers are now built in a case not much larger than a package of cigarettes. Where miniaturization is not practicable, redesigning and re-engineering have in some instances reduced by a factor of four the panel space required by individual instruments. In many cases additional receiving units in the instrument case have made multiple readings possible, sometimes for entirely different types of measurements. Improved design and construction of instrument cases were also noticeable. Many displayers accented the functional design of their instruments. Rounded corners, large windows, minimization of external knobs and dials, dust shields, and other
5240
design improvements were frequently featured. Stainless steels were much in evidence and some instruments, intended specifically for the chemical industries, were completely made of anticorrosion alloys. Improved physical protection for the instruments is in many cases accompanied by simplification o f the actual control and metering unit. Many of the n e w instmments incorporate self-checking circuits that permit routine accuracy checks without special equipment. Component parts, like magnets and coils, are bigger and more rugged and many changes have been made t o reduce sensitivity to vibration. Minneapolis-Honeywell led the "miniature" advocates with a strip recorder using a four-inch tape. The entire unit requires only about six inches b y six inches of panel space but still gives reading within lty of instrument accuracy. The recorder, of course, can be attached t o any type of metering instniment. I t is being promoted particularly for use in pictorial panel boards. Brooks Rotameter Co. also has a contribution to the flow-sheet control hoard. It is a flush mounted purge meter, in which the meter lines and orifices are all drilled into a single block of plastic. The alternative approach to space saving is represented by Fischer-Porter who introduced a brand-new controller which combines almost all o f the functions they could think of into o n e instrument. The entire controlling mechanism is an integral unit about the size of a square milk bottle which can b e either mounted in the recorder case or a t the point of measure-
CHEMICAL
ment. T h e case is arranged so that t*xO o f these units can b e mounted wîîli a sàngie recorder. T w o pens would then record two completely independent croantàâes. By a simple adjustment o n e or both o f the control units cran b e set t o control pinoportionally, for reset, deovaeVeiy or b y any combination of these bases. The most spectacular cxHitributâon £0 multifunction instrumentation w a s Mimiaeapolis-HoneywelTs 2β0-ρο>ΐοΐ ireoonies·. This instrument records data from ainaocst a hundred more metering points than pre vious recorders. T h e record is by numabered imprint- Set for se«|uentiai opera tion, t h e device is intended primarily for use in conjunction with a marâmimm o r minimum alarm. Another alarm d e v i c e was that displayed by Brooks-Rotanieter for small liquid Sows in the range 0.3 millimeter to 3.0 millimeters per minute. The meter oses a metal float that is suspended between cous when t h e flow rate i s within pie-esfcai>lished limits. With t h e float acting as a core trie circuit is oscillating, but if it moves out of range of the coils the csicnit goes o u t of tune and activates the alanm. Chemical Analysis N e w devices for continuous cheamical analysis were featured in several of tiae booths. Beckman has succeeded in taking the absorption spectrophotoineter o a t o f the laboratory and into t h e plant. Their flow-colorimeter will take a small by-pass line from a process flow and record per cent of light transmission or operate cosatirolless. Light source bands can be controlled t o a minimum of 10 millimicrcms within tise range 3 2 0 t o 1000 millimicrons. Another n e w wrinkle in OOUUMIBOHS chemical analysis is Industrial Instrumentas electrolytic cell for measuring a d d c o o tent in sulfuric acid solutions at pressures up to 5 0 pounds gage. Other such cells will o n l y take t w o t o three pounds p i e s sure. "The trick is i n a design isolating the pressure seal from the glass cell body.
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