Gas-Washing Apparatus with Enclosed Filter. - American Chemical

the abscissa. The charts are presented for the purpose of lighten- ... Pittsburgh. GAS-WASHING APPARATUS WITH ENCLOSED FILTER1. By E. R. Weaver and...
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T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y

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t h e excess t i t r a t e d with equivalent alkali. T h e alkali r e a d i n g is t h e n looked u p o n t h e ordinate of t h e chart prepared for t h e feed of t h e particular moisture cont e n t found, a n d t h e c r p d e protein reading m a d e on t h e abscissa. T h e charts are presented for t h e purpose of lightening t h e labors of other chemists doing similar work, a n d t o suggest this simple m e t h o d for calculating results, as a n entire set of c h a r t s can be prepared in a very s h o r t time. DEPARTMENT OF CHEMISTRY, UNIVERSITY OF PITTSBURGH

GAS-WASHING APPARATUS WITH ENCLOSED FILTER’ By

E. R . WRAVERAND J. D . EDWARDS Received February 15, 1915

T h e three f o r m s of gas-washing a p p a r a t u s illustrated, a l t h o u g h involving no new principles, are believed t o be s o m e w h a t novel i n f o r m a n d t h e y h a v e given such satisfactory service t h a t a description of t h e m m a y be of interest t o other chemists, especially as showing t h e a r r a n g e m e n t of t h e p a r t s for various uses.* T w o of t h e f o r m s p e r m i t a filter t o be placed within t h e a p p a r a t u s b y means of which a precipitate m a y be s e p a r a t e d a n d washed w i t h o u t exposure t o t h e air. T h i s feature, in a simple a n d efficient gas wash bottle, is ,believed t o be new a n d h a s been f o u n d useful f o r various purposes. All of t h e f o r m s illustrated possess t h e following advantages: I-They give t h o r o u g h washing b y keeping t h e gas in contact with t h e liquid for a long t i m e a n d yet t h e y

require b u t a c o m p a r a t i v e l y small pressure for their operation. 2-They provide v e r y efficient circulation of t h e absorbing liquid, which p r e v e n t s t h e s a t u r a t i o n of one portion of t h e liquid while a n o t h e r portion remains unsaturated. 3-They c a n be filled or e m p t i e d w i t h o u t disconnecting, a n d , indeed while in use if t h e t u b e for int r o d u c i n g t h e reagent is arranged as shown in Figs. I1 a n d 111. T h e a p p a r a t u s illustrated in Fig. I is designed t o Published b y permission of the Director, Bureau of Standards. * S e e also Cumming, Ckem. News, 101 (1910). 39; J. D. Edwards, THISJOURNAL,6 (1914). 468; Purves (Gray’s apparatus), Gas World, 60 (1914). 897. 1

Vol. 7 , KO. 6

t h o r o u g h l y wash a s t r e a m of gas with a minimum a m o u n t of liquid a n d with t h e lowest possible operating pressure. T h e series of bulbs blown along t h e t o p of t h e absorption t u b e aid t h e a b s o r p t i o n b y prolonging t h e t i m e of contact between gas a n d reagent, b u t d o n o t p r e v e n t t h e a p p a r a t u s f r o m draining completely. T h e construction is so simple t h a t t h e a p p a r a t u s m a y be readily m a d e up f r o m glass t u b i n g . Fig. I1 illustrates a simple washing a p p a r a t u s designed for t h e precipitation a n d determination of acetylene or carbon dioxide, t h e precipitate being filtered off a n d washed w i t h o u t exposure t o t h e air. A W i t t plate a n d asbestos filter a t t h e drain cock are covered with a layer of glass beads or a n o t h e r W i t t plate t o p r e v e n t t h e filter being loosened b y t h e circulation of t h e liquid. T h e b e a d s near t h e outlet serve t o b r e a k u p t h e gas bubbles a n d p r e v e n t loss of liquid, a s well as furnish additional surface. When t h e absorption is complete, t h e stopcock on t h e outlet is closed, t h e stopcock below t h e filter o p e n e d , a n d t h e filtration allowed t o proceed u n d e r t h e pressure of t h e inflowing g a s ; suction c a n be used if desired. Washing is accomplished b y i n t r o d u c i n g wash water t h r o u g h t h e funnel t u b e near t h e gas outlet, t h e liquid being forced t h r o u g h t h e filter b y gas pressure as before. A straight a b s o r p t i o n t u b e is used instead of t h e bulb t u b e shown in Fig. I because of t h e difficulty of washing a precipit a t e clinging t o t h e bulbs. A helical wash bottle, Fig. 111, is t h e s a m e in principle a n d operation a s No. I1 b u t h a s been designed with a view t o economy of space. T h i s a p p a r a t u s is very c o m p a c t a n d efficient, giving as complete a b sorption as several o r d i n a r y wash bottles in series, while requiring only a small fraction of t h e pressure necessary t o operate t h e l a t t e r . W i t h gas flowing a t t h e r a t e of I O O cc. per m i n u t e t h e bubbles remain in t h e helix a b o u t seven seconds. Bubbles passing a t t h e r a t e of one or t w o per second remain in t h e t u b e nearly t w e n t y seconds. G a s passed a t t h e r a t e of joo cc. per m i n u t e is still broken into fairly small bubbles a n d receives a v e r y t h o r o u g h washing, b u t if t h e gas is t o be passed a t a more rapid r a t e t h a n this t h e helix should be m a d e of t u b i n g of larger diameter. T h i s f o r m of a p p a r a t u s is much easier t o m a k e t h a n , a n d quite as efficient a s some of t h e more elaborate a p p a r a t u s on t h e m a r k e t in which t h e gas bubbles follow a helical p a t h . It possesses t h e additional a d v a n t a g e of p e r m i t t i n g t h e filtration a n d washing of a precipitate within t h e a p p a r a t u s w i t h o u t exposure t o t h e air. F o r satisfactory operation, it is necessary t h a t t h e d i a m e t e r of t h e absorption t u b e in all three forms be properly proportioned t o t h e r a t e of gas passage. T h i s t u b e should n o t be made t o o small. A t u b e

J u n e , 191;

T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y

with a n i n t e r n a l d i a m e t e r of 8 t o I O mm. w a s f o u n d t o work v e r y satisfactorily at r a t e s of less t h a n joo cc. per minute. T h e t i p of t h e inlet t u b e h a s an internal d i a m e t e r of I t o 2 m m . T h e size of t h e other p a r t s

I By RAYMOND F. B A C O I ~ ~

The industrial researcher, who deals with the processes of manufacture and the phenomena of reactions involved, is becoming less and less regarded as a burden unwarranted by returns. The aim of every industrial operation is toward perfection, both in process and the necessary mechanical equipment, and every new development in manufacturing creates new problems. It follows, then, that the greater the number of researches, the greater is the progress in a given field, and the greater becomes the number of new problems. Moreover, one can only conclude that, since perfection is but, after all, an ideal, no industrial field has been sufficiently investigated. The thirst for distinction and wealth kindles the lamp of invention, and t.he light of the knowledge resulting from discoveries and improvements in manufacturing operations has so emboldened us that some industries now consider themselves capable of solving any problem. This has been shown in innumerable instances, but is particularly true of the great chemical industry, which, while its achievements have been stupendous, is nevertheless confronted with many problems of importance. With your permission, I shall restrict myself to recounting some of the problems which engage the attention of the present-day chemical industrialist-problems which he is capable of clearing up, provided fhe service of research is called to his aid, but which have so far remained unsolved. I n collating these I have drawn from all available resources of information and from my own experience. SOME METALLURGICAL P R O B L E M S O F TODAY

While there may not be a t the present time room for such abnormal discoveries in siderurgy as in the past, investigators are quietly and steadily augmenting our knowledge of iron and its alloys, and the value of such research work is generally recognized. Elaborate investigations are constantly being conducted by several manufacturers, especially by the United States Steel Corporation, which has to date expended over $800,0oo in studies on the electrothermic production of steel alone. However, metallurgical research laboratories are still comparatively uncommon. Very few iron furnaces or smelting plants are without a control laboratory, which has come about notwithstanding the opposition of “practical men,” and the research laboratory will eventually win a similar victory. Such problems as the working-up of blast furnace slags by an economic process could probably be solved by systematic research. The great problems a t present in the metallurgy of zinc are in concentration of the ore and in the treatment of flotation concentrate. The latter produces the troubles that fine ore always does; it is difficult to roast, and t h e distillation of it is attended with troubles. Viewing the present status of the practice in zinc smelting, one is impressed by the high extraction results, the low fuel consumption made possible by regenerative gas-firing, and the reduction of labor involved in the art. In copper metallurgy, the leaching of copper ores and electrolytic deposition for precipitating are receiving increased at-



Author’s abstract of an address delivered before the Chicago Section thv American Chemical Society on May 14, 1915. I n Dr. Bacon’s abwncr. this address was presented b y Dr. S . K.Scholee, Assistant Director of the Melion Institute. Director of the Mellon Institute of Industrial Research and School of Sprciljc IndIistries of the University of Pittsburgh. of

of t h e a p p a r a t u s mill d e p e n d primarily on t h e a m o u n t of reagent, a n d the d u r a t i o n of c o n t a c t between g a s a n d reagent, which is desired. BUREAUOF

STANDARDS

\~ASHINGTON,

D

c

ADDRESSES SOME PROBLEMS OF CHEMICAL INDUSTRY1

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tention. With regard to chemical precipitation, it is desirable tha,t this process be conducted in such a way as to regenerate the solution. In electrolytic copper refining, promising progress has been made in the treatment of anode slimes, and increasing attention is being paid to the recovery of by-products. Then, too, the progress in the development of flotation processes has been phenomenal, but still our knowledge regarding flotation is meager. The search for platinum substitutes continues, and an economic method for rapidly separating the metals of the platinum group is also desired. The brass industry has been carried on for more than a century in Connecticut and considerable study has been given the matter of zinc loss, but so far ones engaged in the industry have been unable to find any economic and entirely satisfactory method to overcome such loss. Moreover, no entirely satisfactory gas furnace has been designed for general brass rolling mill practice. The development in engineering construction has arrived a t a point where the use of special alloys for specific requirements requires more thorough investigation. The matter of corrosion has been one of a more or less mysterious nature; confusion has arisen on account of the names of alloys; the ideal alloy for condenser tubes has not been found; the failures of screens made from brass wire are well known, and we have yet to find an aluminum alloy that will resist alkalies. It is true that there is beginning to be a well-defined literature on the subject of alloys and that now one can sometimes very closely predict the properties of combinations of the more commonly known metals; but we have not begun to open up the possibilities of usefulness in the exploration of the alloy field, in which I include the socalled “dilute alloys”-cases wherein a very small amount of a metal alloyed with, say, iron or steel confers upon it some new or unusual properties. S O M E P R O B L E M S O F I N D U S T R I A L I N O R G A N I C CHEMISTRY

Nitrous oxide is being successfully used in combination with oxygen for the production of anesthesia; but while there is a material available for the production of oxygen upon treatment with water (“oxone”), no substance which will yield nitrous oxide upon similar treatment is known. On account of the present large consumption of nitrous oxide, considerable study has been devoted to this problem. Xew uses, ones such as would increase the demand, for the following products are required : Potassium hydroxide, chlorine, bleaching powder, bromine and bromides, calcium, silicon, selenium, tellurium, cobalt, uranium and molybdenum. Since sodium metantirnonate is undesirable in enamels placed on cooking utensils, new uses for this and other antimony compounds are needed; attention may be directed to the fact that antimony lithopones, made by treating barium carbonate and antimony sulfite, offer, perhaps, a partial solution of this problem. It may be noted here that a large production of arsenic would follow a demand. In the domaic of ceramics, the subject of binders presents a field for research; to cite a simple instance, a binder for infusorial earth that is cheap andwill stand a temperature of about 3,000’ F. is being sought for by ones interested in the production of metallurgical brick Efforts to improve the quality of all varieties of clay goods. from ordinary brick to the highest-grade pottery, are constantly in progress by American clay-workers; this is evinced by the new