T H E JO17RS.-1L O F I S D L * S T R I . I L
Sepi.. 191 j EXPERIXESTS
O S
THE
DEODORIZATION
OF
DRYER
GASES
On passing clrler gas through several bottles of n-ater its odor was practically all removed. I n t h e same way t h e odor was destroyed b y mcans of a solu-. tion of calcium hypochlorite (bleaching powder) containing I p a r t of available chlorine in 1000. B y leading t h e gas across pine t a r oil its characteristic smell was replaced b y t h a t of t h e oil. T h e latter result suggested t h a t mineral oil of t h e paraffin oil or light engine oil class might ha\-e sufficient solvent effect on t h e odorous substances t o make their use in a scrubber possihle. T h e effect of mineral oil was not in1-estigated because of lack of time. T h e action of heat on dryer gas was observed using t h e same a p p a r a t u s as for t h e digester gas. I t was in this case necessary t o draw t h e gas through t h e t u b e furnace. T h e results are given below: EFFECTOP HEAT ox T e m p . in furnace
' F. 40
T e m p . of gases a t point where odor was noted
I50
52
7i0
60
72
4.50
86 86 86 84
;SO 6.50 7.50 8.50
ODOR OF DRYER GASES
~ - A T U R E OF
40° F.
350
THE
Sweet, slightly irritating, burned
'g:
Irritating, acrid, slightly burned Very irritating, acrid, burned
Y.50 I 050 I IS0 1250 I150
93 116 I20 116
( S o t quite so irritating or acrid, only slightly
14511
122
j
ITTII
129
, V e r y irritating b u t not quite so burned I
burned Only slightly irritating a u d acrid, no burned odor . -
~
~
Less irritating t h a n a t I550O F Practically no irritatina odor 18511 S o odor of any kind S o sulfur compounds were present in these gases I6.ill
17511
147 154 163
Esperimenl s were made t o ascertain if dilution with air, before leaving t h e stack, could be carried t o such R degree t h a t t h e dryer odor would be unperceptihlc. Gas a n d air were passed separately through in. t u b e : meters and t h e n mixed in a 4 f t . length of and t h e odor noted. T h e d a t a obtained, f o l l o ~ ~ - s : K a t e of flow, cu i t . per tnin. Ilryer pas Air 12
I?
12
Dilution of dryer gas t o air 1 : 20 I ' 60 1 : 400
CESTRALTESTING LABORATORY CITY O F SEW YORK -~
TWO CONVENIENT FORMS O F RECEIVER FOR FRACTIONAL DISTILLATIONS UNDER DIMINISHED PRESSURE By
ODOR
Slightly burned
[
nc :leaned. X concrete floor with n freqLlLed t a r coat or one of asphalt would be a n e n t on the IT-ood. great i m p l . In conclusion, we n-ish t o acknowledge our indebtedness t o N r . Osborn for his invaluable suggestions, advice a n d inspiring interest in this investigation. We also wish t o t h a n k 11r. Thomas D. Banks, Superintendent of t h e Garbage Reduction Plant of Columbus, 0.. for valuable assistance. a n d hIr. George n'oocl. Assistant Engineer in t h e Department of Street Cleaning of this city. for aid in carrying out t h e experimental work a n d for t h e sketches accompanying this paper. T o N r . Charles Crew, of this laboratory, n-e are grateful for t h e performance of analytical determinations.
Intensity of dryer gas odor Very strong Strong Distinct
T h e results s h o ~t h a t no reasonable a m o u n t of dilution with air is effectiye in causing t h e dryer gas odor t o become negligible. O D O R S . i R I S I S - G F R O M P E R X E A T I O S OF T H E R E D U C T I O S
TVORKS STXL-CTLTKE TVITH L I Q U I D S . E T C .
Brief mention m a y be made of t h e odors resulting iron: t h e permeation of the buildings of reduction works x i t h liquids. etc. The wind passing over t h e plant may in this w a y t a k e u p considerable odor, even n-hen n o garbage is present or in process. T o eliminate this source of trouble garbage plants should be of t h e most sanitary construction t o permit n-ashing and prevent material lodging in crevices. T h e cement of concrete floors is readily attacked b y t h e stick liquor a n d garbage, a n d wooden floors are sometimes p u t down. As m a y be easily understood, these soon become of a 7-ery objectionable nature a n d can-
TAYLOR BOGEKT Received June 16, 1915
h1ARSTOS
Having had occasion recently t o carry out many fractional distillations of t w o or three liters of liquid a t a t i m e , under reduced pressure, t h e writer could not find upon t h e market a n y form of receiver which would permit t h e taking of a large number of fractions, of varying volume. without interruption of t h e distillation. T o meet this need, t h e forms described below were del-ised ar,d have proven very serviceable. Possibly, other chemists confronted with similar problems, also m a y find t h e m of use. .APP.AR.ATUS I is constructed entirely of glass resistant t o t h e action of chemicals. well tempered, and sufficiently strong t o withstand t h e full atmospheric pressure. Ordinarily, t h e connections with t h e end of the condenser (or distilling t u b e ) , a n d v i t h t h e lower vessel into r h i c h t h e fractions are t o be drawn. will be made xvith perforated rubber stoppers; b u t , if desired, t h e y can of course be made with ground glass joints. I n detail, t h e a p p a r a t u s consists of a cylindrical receiving chamber, d , graduated in cc. a n d with a funnel stem through which the distillate collected in -4 m a y be removed a t will b y opening the plain cock F . On one side of this receiving chamber, near the ' t o p , is t h e U Frc. I opening B , for t h e end of t h e condenser F r o m t h e t o p of t h e receir ing chamher . I , the t u b e C passes t o t h e p u m p P a n d t o the outer jacket E of t h e funnel stem. On this t u b e C, there is a plam cock a t H . a n d a 3-way cock with offset ports a t D . By turning this 3-way cock 9 0 ° , connection is established b y means of a perforation in t h e stem of t h e cock, between t h e
7 86
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
outer air a n d , through t h e outer jacket E , with t h e lower receiving vessel. I n t h i s w a y , atmospheric pressure can be restored t o t h e lower vessel without i n a n y way affecting t h e v a c u u m t h r o u g h o u t t h e rest of t h e distilling system. T h e lower vessel can t h e n b e removed, or i t s contents drawn off, as t h e case m a y be. T h e effect of t h i s arrangement of t h e 3-way cock, therefore, is t h a t i n one position only does i t make connection between t h e p u m p a n d t h e lower receiver; a n d in one position only, between t h e l a t t e r a n d t h e outer air. I n all other positions, it merely seals t h e t u b e at D. T h e manipulations are as follows: T h e e n d of t h e condenser (or distilling t u b e ) is inserted through a rubber stopper i n B , a suitable receiving vessel is a t t a c h e d t o t h e funnel s t e m , also b y means of a rubber stopper, t h e p u m p is connected at P , a n d t h e entire a p p a r a t u s evacuated, t h e 'stopcock F being closed, t h e stopcock H open, a n d t h e 3way cock D being t u r n e d so a s t o establish connection between t h e p u m p a n d , through t h e outer jacket of t h e funnel stem! t h e lower receiving vessel. When t h e first fraction has been collected i n d , a n d i t s volume read, i t can be r u n i n t o t h e lower receiving vessel simply b y opening t h e stopcock F . If t h e first (or a n y subsequent fraction) proves greater t h a n t h e graduated capacity of A , t h e l a t t e r can be filled a n d drawn off a s m a n y times as m a y be necessary; or, if preferred, t h e stopcock F m a y be left open during t h e taking of t h e fraction, allowing t h e distill a t e t o r u n right on through A F i n t o t h e lower receiver. After t h e first fraction has all been r u n into t h e lower receiver: t h e stopcocks F a n d H are closed, a n d t h e 3-way cock D t u r n e d so as t o close t h e connection between t h e lower receiver a n d t h e FIG.I1 p u m p a n d open t h a t t o t h e outer air. This allows t h e air t o flow into t h e lower receiver, a n d t h e l a t t e r can t h e n be removed, emptied Meanwhile, a n d replaced, or a new one a t t a c h e d . t h e distillation has not been interrupted in a n y way nor t h e v a c u u m affected, a n d t h e distillate is accumulating i n A . When t h e new receiver is connected below, it is first evacuated b y turning back t h e 3-way cock t o its original position, after which stopcock H c a n be opened again, a n d t h e fraction accumulated in il drawn off as before. If t h e new receiver a t t a c h e d below is large in comparison with t h e capacity of t h e p u m p , a n d t h e operator SUSpects t h a t ' l e a k s may be altering t h e pressure in t h e distilling system (since t h e p u m p is cut off at H ) , he can test t h i s for himself a t a n y moment, without losing a n y of t h e evacuation of t h e lower receiver already gained, b y turning t h e 3-way cock so as t o seal t h e t u b e at D , waiting a moment until t h e pressure gauge has fallen again t o t h e initial pressure i n t h e distilling sys-
,'
1
,
Vol. 7, NO.9
t e m , a n d t h e n slowly opening t h e stopcock H . Any loss of pressure will t h e n be immediately apparent. I n case t h e r e h a v e been leaks a n d t h e pressure has changed, stopcock H is left open until t h e desired .evacuation is restored, after which it is closed and t h e exhaustion of t h e lower receiver resumed. W i t h this a p p a r a t u s , a n y number of fractions m a y b e t a k e n , of a n y desired volume. B y using a separat o r y funnel, or similar vessel, as t h e lower receiver, t h e fractions can be drawn off a t will without removing i t at all. T h e writer has found 2 5 0 cc. a very convenient size for t h e receiver. An a p p a r a t u s of this capacity is a b o u t 1 5 in. high over all, a n d t h e diameter of A is approximately z i n . , so t h a t it is easily held b y an ordinary Liebig condenser clamp. A P P A R A T U S I 1 is a somewhat simpler form, for use in laboratories which, like t h a t of t h e writer, happen t o be equipped with more t h a n one p u m p . T h e 3 way cock D may be set as indicated either in Fig. I or Fig. 11. I n this t y p e of a p p a r a t u s , after t h e removal of t h e first fraction, t h e lower receiver is evacuated b y connecting t h e auxiliary p u m p with t h e hollow s t e m of t h e 3-way cock, after which it is t h r o w n again into t h e distilling system b y turning t h e 3-way cock back t o its original position. Both forms of t h e receiver are manufactured b y t h e Emil Greiner Co., j j F u l t o n S t . , Xew York, N.Y . COLUMBIA UNIVERSITY, NEW PORK CITY
A SIMPLE AUTOMATIC-ZERO BURETTE By A. T. MERTES Received May 7 , 1915
Most automatic-zero burettes discharge t h e overflow f r o m t h e b u r e t t e into a receptacle separate from t h e main reservoir, a n d t h i s excess is either t h r o w n away or is poured back into t h e main supply. For solutions t h a t have been carefully standardized, this practice is inconvenient a n d m a y be a source of error. T h e accompanying drawing shows a n automaticzero b u r e t t e t h a t discharges t h e overflow back into t h e main reservoir. I t has t h e a d v a n t a g e t h a t i t m a y be protected from t h e carbon dioxide of t h e air, a n d hence is especially a d a p t e d for use with s t a n d a r d acid a n d alkali solutions. I t consists of a large Woulfe bottle having a b u r e t t e a t t a c h e d t o i t s neck b y a clamp. T h e b u r e t t e has a side aperture which connects, b y means of rubber t u b i n g , t o a goose-neck-shaped glass tubing, A , a b o u t 5 m m . in bore. This is b e n t in such manner t h a t t h e ring of t h e pinch clamp encircles i t a n d is t h u s prevented from rotating. Half way between t h e b u r e t t e a n d where t h e connection tube, A bends'down i n t o t h e liottle a n inner t u b e , B , is fused. This inner t u b e is about I m m . i n bore. It connects with a short a r m , C, forming a T with t h e main tube. T h e lower ext r e m i t y of t h e inner t u b e B is fused t o t h e outer t u b e a t D i n such a way t h a t it opens outside this t u b e . This prevents air bubbles t h a t m a y be drawn through t h e inner t u b e from rising in t h e main supply tube. T h e t o p of t h e b u r e t t e is closed b y a cork, E , through
