Separators Often Used ~n Oil Relineries
S a m e A~rangementMade
of Welded Pipa
men have tx,t. been able to advance their knuwletigc and skill :inrinlingIy. To correct t, on and to iustriict. t,hc shop fr,rcmen as well as the uc of the Icarling mup:uiies proditcing oxygen a i fimes of crrrripetcnt engineem and :tvailnhle on request for exp
serrice man may also result pairs with great savings in time and cost.
Original Frederking Apparatus
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HE ubject of this paper is to give a brief description and present the possibilities of Original Frederking apparatus, also to show what frtctori must be studied to determine whet,lier it can advantageously replace existing jacketed or direct-fired equipment for any particular process. An actual study of any process inudves operating and performance data, which are beyund the scope of this discussion. Tire name “Origirral Frederking” is applied to all castirou vessels, of any form or size, iraxring a mries of steeltubing coils cast in the walls according to methods originally used in Germany by the Frederking Brot.hers and perfected in 1904. In t.he manufacture of this equipment attention must be aiveii to coil construction, becairse of difficulties which are-’encountered, and the surface of the tubes must bc specially treated before t,he assemhled coils are placed in tlic mold. Foundry practice, especially iriet,hods of molding and pouring must he carefully studied fur each easting. For the past twenty years t.he chemical indilstry of Germany has been using apparatus of this construction, and it has been found advantageous fur so many prmesses that several foundries have t,akeii up its mamifact.ure. Heating Medium
We will consider only the use oF either &urnrated steam or hot water as a heating medium. The former is the more common heating medium, and it is essential that the prospective user bear in mind that the cast-iron tubes are fully capable of withstanding high pressures. The tubes which conduct the heating medium are arranged in a series of individual coils a i d connected in parallel to supply and discharge
hedcrs. Expcrieirce has ~leinansbrateil that to give maximum efficiency or rate of heat transfer a coil must not be too long. Moreover for m y given surfam the transfer rate, under the same operating conditions, will he iricrcased when there are a number of live-steam inlets distributed over the surface. The surface tempcraturc of the vessel is practically uniform since the drop in temperature tlirough each coil is comparatively low and there is a tendency to equalize through t.he cast,-iroii wall. The Faet t,liat the tubes are desigued tu withst,and high pressure offers an opportunity for increasing the production from a giveri unit of apparatus, especially when the process is one of drying, distilling, or evaporating, which may be accelerated by t,he use OF high-pressure steam, thus increasirig . the uver-all temperature difference. Steam Heating and Cooling Operations 111 the chemical industries many processes involve tire use of large, jacketed, xrertieal stills or horizontal cylinders for stealri pressures ranging from 1W to 200 pounds per square inch, and such equipnlerrt uBually drveiops ie&y joints, causine a loss of steam as well U S maintenance exneiise in attempting repairs or to give the area around the apparabus a more sightly appearance. These conditions are ahsolutely eliminated by the use of Original Fredcrking apparatus. Operations of such character often include cooling at some stages, and this is likewise accomplished to advaut,age by the use of the casein coil equipment. When a mass is to he cooled or a reaction develops heat at a rapid rat,e so that there is danger of overheating the material: Original Frederking apparat,us proves itself very efficient, since by
June, 1927
I S D L’STRIA L AATDENGINEERISG CHEMISTRY
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to design equipment safe for high pressure. Therefore, a hot water system with a reasonable factor of safety should not be considered so much of a hazard as a steam boiler plant since the total energy content of the former is much less. Applications
Original Frederking apparatus, heated with steam or hot water, may be used in processes involving the manufacture of the following products: Acetic acid--S-acuum distillation with steam Formic acid-Vacuum distillation with steam Salicylic acid-Vacuum distillation with steam Continuous sulfonation of oils-Cooling process Synthetic camphor-Steam heating Dyestuffs-Hot water heating, particularly those processes requiring temperature control; also applications of steam heating Concentration of caustic lye--Vacuum evaporation with hot water as heating medium distillation with hot Distillation of fatty acids-Vacuum water as heating medium Varnishes and lacquers-Hot water heating Hardening animal oils-Hot water heating Sublimation of benzoic acid-Hot water heating
Typical Elevation, Bethlehem Hot Water System, with Original Frederking Vessel
for the reason that the heating medium never leaves the system. K i t h recent developments of handling gases under high pressure due t o the development of such processes as nitrogen fixation. it i. not conridered beyond the ability of engineers
This is only a partial list of European uses. Up to this time a limited number of applications have been attempted i n the United States, and in practically every instance the equipment has been considered successful. The use of superheated steam as heating medium has not heen discussed since its application is economical only under favorable plant conditions, but it is of interest to note that Original Frederking apparatus is so constructed that it pre.sents an efficient means for using superheated steam. The methods of manufacture used for all castings produced by this company are protected by United States patents.
Electrical Equipment in the Chemical Industry and in Chemical Processes By R. H. Rogers GENERAL ELECTRIC COMPANY, SCHRNECTADY, N. Y.
HE manufacture of chemicals and the utilization of chemicals in manufacturing present fields for special consideration in regard to electrical equipment. Most of the motor and control applications in industry are not subjected to particularly detrimental conditions and therefore in the interests of economy are not armed against foes that will never be met. The nature of chemical manufacture and use is such that in many cases ordinary electrical equipment might either be harmed or cause harm; hence we will analyze characteristic conditions and characteristic procedure. The mechanical equipment involved is great in both variety and quantity and the majority of it requires electric motor drive and control which are often operated in conditions detrimental to long life and successful service. These menaces common to chemical production and chemical processes may be catalogued in general family groups:
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A-L?guzds such a s aczduluted or alkali water, Oils, sohents. These liquids may quickly or by accumulative effect over a long interval spray or drip upon or into electrical equipment or even flood parts or entire units B-Fumes and uapors These may be of solvent nature, corrosive, steamy, or inflammable. They may thoroughly wet all parts of the electrical equipment or in the case of explosive vapors they may be set off by unguarded sparks or flashes from the equipment itself.
C-Dusts While seemingly of benign nature, dusts under certain circumstances and given time can work havoc with electrical equipment, especially if the dust is conductive or, worse, magnetic, such as the impalpable dust of cast iron Abrasive dusts are obviously bad and explosive dusts, which are now believed to include almost everything metal, mineral, or organic, have particularly to be guarded against D-Hzgh temperature So many of the unit processes involl-e heat in greater or less degree i t is inevitable that attendant electrical apparatus will often be subjected t o temperature much higher than the classical standard of 40’ C.
The effects of these conditions and the methods of coping with them will be discussed in the order of this outline. It must be remembered that it is practically impossible to make apparatus “proof” against any particular condition. It can be made highly “resistant” to such a condition. The aim is to prolong the life of the apparatus, by the use of special insulation and construction, to what may be considered a reasonable length of life for the specific conditions. r l p p a r a t u s where Liquids Are Encountered
IDS AKD . & L K A L I E S - ~ ~ ~liquids ~ ~ ~ ~ are liable to spray, drip, or splash directly on the motor, as is often the case with direct-connected pump outfits, the low-voltage, totally enclosed motor with special insulation is undoubtedly beqt, unless heavy fumes are alqo present. However, there are
