T H E J O U R N A L O F I A V D K S T R I A L AAVD E L V G I N E E R I N G C H E ; I J I S T R Y
J u l y , 1914 TABLEII--SUMBER (2240 LBS.) O F
OF
Rise in temperature 7 -
' F.
= c.
950 1050 1150
528 584 639 695 i50 806 834 86 1 889 916 945 972 1000 1306
1800
2350
KILOWATTHOVRSREQUIREDTO RAISE ONE T O N
TEMPERATURES AT SEI'ERAL EFFICIENCIES
STEEL TO VARIOUS
Percentage efficiency 7
100 89 103 11s ~~
134 150 164 lil 178 188 197 207 21i 222 272
~-
80 70 60 Kilowatt hours reauired 148 li2 196
50
345 362 3 70 453
I n general, t h e larger t h e production of metal in a particular furnace, t h e greater t h e electrical efficiency. Too high production, however, usually means difficulties in control a n d with very high production there is danger of overheating should there be slackening i n t h e production without a corresponding change in t h e kilowatt i n p u t being made. T h e aim t o make a production at a r a t e equivalent t o 4 or 5 k . w. per sq. f t . of hearth a n d also at 6 5 t o 7 5 per cent efficiency is a n excellent one. When t h e cost of current is rather high, work which necessitates a production a t a lower efficiency t h a n 60 per cent should be transferred t o a smaller furnace if t h e shape of t h e pieces permits. On furnaces under 30 k . w. capacity these figures d o not apply, a s t h e efficiency on such small furnaces is very much less t h a n on t h e moderate size ones of jo t o 1 2 j k . W. INSTALLATIOX O F FURNACES
I n order t o determine t h e n u m b e r a n d size of furnaces for a n installation a careful inquiry into t h e n a t u r e a n d q u a n t i t y of t h e production is necessary. T h e maximum a n d minimum productions must be met mith as high efficiency a s possible for t h e various productions. Frequently a moderately large furnace t o operate all t h e time, accompanied b y a smaller one t o be operated as needed, is much more economical from a point of view of current consumption in t h e long run, t h a n one furnace capable of t h e maximum production. Care m u s t be observed not t o make t h e furnace t o o large for t h e sake of being o n t h e safe side. A furnace so large t h a t i t t a k e s I O per cent more current t h a n a smaller one exactly suited t o t h e work, would waste enough current in t h e course of six months, or a year a t t h e outside, t o p a y for a complete new installation. Sometimes t h e labor requirements determine t h e size of t h e units. T w o men on a single furnace might not be able t o accomplish so much on t h e one furnace as t h e y would if operating t w o smaller size furnaces. Here t h e decreased efficiency in t w o furnaces m u s t be carefully compared with t h e saving in labor. SELECTIOX OF TYPE OF FURNACE
I n t h e selection of t h e t y p e of furnace for t h e particular work, if I O sq. f t . or more of hearth area are required, a furnace regulated b y t h e resistance method, Fig. 111, is certainly to be preferred. This furnace costs a b o u t half as much a s t h e furnace equipped with a transformer a n d has a much more uniform heat liberation in t h e hearth. Electric furnaces with re-
541
sistance regulation including all t h e electrical equipment, cost a b o u t t h e same for installation as a good oil furnace, a n d frequently are somewhat cheaper if blowing equipment installation charge for t h e oil furnace is included. As a rule these furnaces operate on a higher voltage t h a n do t h e furnaces having a special transformer so t h a t a saving in copper for t h e conductors is sometimes effected. T h e y can be designed t o operate on t h e s t a n d a r d voltages, 2 2 0 volts being very satisfactory, a n d , of course, can operate on either direct or alternating current. T h e larger furnaces can be built t o operate on two- or three-phase lines, b u t those taking 100 k. w. or less are best constructed for single-phase or direct current. For t h e small furnaces, such as t h e one shown in Fig. I\-, a regulation b y means of voltage is best with a transformer having a secondary with several taps, as mentioned above, either with or without t h e resistance regulation in conjunction with i t . USE
OF
ELECTRIC
FCRNACE
FOR
HE4T
TREATYENT
D E P E h - D E N T O K COST O F C U R R E K T
T h e extent of use of t h e electric furnace for heat treating depends quite largely on t h e cost of current. Fortunately, i n this connection, t h e resistance furnaces have a remarkably s t e a d y load. T h e starting load is somewhat less t h a n t h e running load. I n a large n u m b e r of cases t h e mean running load is found t o be between 80 a n d 9 0 per cent of t h e maximum demand. Under these circumstances, particularly with operation extended into or through t h e night, current can usually be furnished for a low figure. T h e price of one cent per k. w. hr. is frequently sufficient t o warrant t h e employment of t h e electric furnace in place of oil on t h e ground of cheaper cost of operation alone. Current for three-quarters of a cent per k . w. hr. frequently proves as cheap a s a n y method of firing when all factors are considered. Among these factors, most of which have been duly considered, might be mentioned t h e lower labor charge which is usually effected b y t h e introduction of t h e electric furnace. T h e furnace is conducive t o high production on account of t h e fact t h a t i t is not so uncomfortable for t h e workmen as t h e fuel-fired furnaces. Besides t h e fact t h a t i t is relatively cool a n d t h e elimination of all smoke a n d dirt, a n d t h e a t t e n d a n t difficulties with t h e products of combustion, t h e electric furnace is much more satisfactory from t h e workmen's standpoint t h a n a n y heretofore produced. ACKSOFVLEDGNEKT-The writer wishes t o express his appreciation of t h e assistance of his associate, M r . Richard S. Bicknell, both in t h e s t u d y a n d design of these electric furnaces, a n d in t h e preparation of this paper. 50 E A ~ 41ST T STREET. S E N
YORK
_ _ _ ~ ~~-
STUDY OF AUTHENTIC SAMPLES OF GUM TURPENTINE By A. U' SCIIORCER
Received March I t , 1914
VARIATIOS I S PROPERTIES
Turpentine, spirits of turpentine, or oil of turpentine, is t h e volatile oil obtained ordinarily b y t h e distillation of t h e oleoresin of various species of pines.
542
T H E JOURNAL OF I N D U S T R I A L A N D ENGINEERING CHEMISTRY
I n recent years a considerable a m o u n t of ‘ ( w o o d turpentine,” obtained b y s t e a m or destructive distillation of resinous wood has been placed upon t h e m a r k e t . To avoid confusion, t h e turpentine obtained b y distillation of t h e oleoresin or gum is called ‘ ( g u m turpentine.” G u m turpentines consist largely of t h e terpene a-pinene, with smaller a m o u n t s of camphene’ a n d P-pinene.* Camphene is not readily affected b y light a n d air, b u t a-pinene a n d @-pinene are soon affected; t h e specific gravity, index of refraction, a n d boiling point become higher a n d there is a pronounced increase in color a n d non-volatile residue. F o r this reason t h e physical properties of gum turpentines will v a r y considerably, depending upon their age a n d exposure. McGill3 collected 48 samples of turpentine on t h e open m a r k e t . After eliminating samples of d o u b t ful purity, he defines turpentine in part a s follows: Density 0.860 t o 0 . 8 8 0 a t 15.5’ C., being usually a b o u t 0.870; density of t h e first fraction consisting of I O per cent b y volume, between 0 . 8 56 a n d 0.870, being usually a b o u t 0.860. T h e refractive index should lie between 1.4667 a n d 1.4722 a t 20’ C., t h a t of t h e first fraction should not exceed 1.4700; boiling point between 154’ a n d 158’ C.; nine-tenths b y volume should distil over below 180’ C. L o y 4 found t h a t t h e specific gravity of p u r e commercial turpentines varied from 0.8656 t o 0.8748. T h e boiling point was uniformly I j 5-1 56’ C.,a n d 8 j per cent distilled below 163’ C. Veitch6 a n d Donk s t a t e t h a t a turpentine of standard or No. I quality should have a specific gravity of f r o m 0.862 t o 0 . 8 7 0 a t 20’ C.; a refractive index of from I . 468 t o I . 476 a t 20’ C.;a n d t h a t 9j per cent should distil below 170’ C. Practically all information previously published on t h e physical properties of g u m turpentine is based on t h e analysis of samples, t h e age of which is not stated, a n d consequently i t is not a p p a r e n t t o w h a t extent variations existed in t h e original freshly distilled oils or t o w h a t extent t h e y are due t o subsequent changes. Although it has been considered t h a t t h e conditions of production exerted some influence on t h e quality of turpentines, t h e extent of such influences h a d not been determined. VARYING CONDITIONS OF PRODUCTIOX
T h e oleoresin obtained b y systematic scarification of t h e trees a n d caught in appropriate receptacles such as “ cups ” or ((boxes,’) is known a s ( ( d i p” among turpentine operators, while t h a t portion of t h e oleoresin which hardens on t h e face of t h e tree is called ‘ I scrape.” Collectively, t h e dip a n d scrape are called < Igum.” When t h e trees are t a p p e d b y t h e box system a cavity called a box is c u t into t h e base of t h e tree. T h e face immediately above t h e box is chipped weekly t o produce a flow of g u m ; as a result, t h e face is exSchimmel and Company, Report, October 1897, p 68 I b i d . , April, 1908, pp. 99-100. Inland Revenue Dept., Canada, Bull 79. 4 Jour. A n a l a n d A p p l z e d Chem., 6 (1892). 2 . ‘Bur. of Chem.. Washington, D. C., Bull. 136.
2
Vol. 6 , NO. 7
tended a n d a height of t e n t o twelve feet is sometimes attained before t h e tree is ,abandoned. T h e height of t h e face increases f r o m 18 t o 24 inches per year, a n d t h e gum must travel a constantly increasing distance t o reach t h e box. T h e dip collected t h e first year is called ((virgin,” t h e second year “yearling,” usually ( ‘ b u c k ” for t h e succeeding years. Because of t h e greater distance t h e g u m must flow during succeeding years, which necessitates longer exposure t o light a n d air; t h e turpentine has a more or less yellow . color a n d is usually supposed t o have a higher specific gravity. T h e proportion of volatile oil in t h e oleoresin collected decreases a s t h e height of t h e face increases a n d t h e rosin has a darker color. T h e employment of t h e cup a n d gutter system o r c u p a n d a p r o n system reduces t h e p a t h , over which t h e g u m must flow, since a t t h e beginning of each season t h e c u p is raised t o t h e t o p of t h e face chipped t h e preceding year. T h e turpentine obtained from this g u m is believed t o be more uniform in physical properties a n d is only slightly colored. T h e g u m is distilled in ordinary copper-pot stills which hold from t e n t o thirty-five barrels a n d are heated directly. A small s t r e a m of water is allowed t o flow i n t o t h e still from a funnel in t h e still head after t h e greater portion of t h e water occurring in ’ t h e g u m has passed over. T h e t e m p e r a t u r e within t h e still usually does not exceed 160’ C . a t t h e e n d of t h e distillation, b u t when old scrape or dip is being distilled a much higher t e m p e r a t u r e is often employed. T h e rosin flowing from one still was observed t o have a t e m p e r a t u r e of 194’ C. T h e species t a p p e d in t h e S o u t h are almost exclusively t h e longleaf pine (Pinus p d u s t r i s Mill.) a n d t h e C u b a n pine ( P i n u s heterophyEla Ell.); t h e shortleaf pine ( P i n u s echinate Mill.), loblolly pine (Pilzus teeda Linn.), a n d t h e pond pine (Pilzus serotina Mich.) are t a p p e d only casually. COLLECTION OF SAMPLES
T h e samples which were t a k e n t o s t u d y t h e variation in fresh turpentines were collected b y t h e a u t h o r a t t h e stills a n d were obtained a t various points in t h e coastal region f r o m Mississippi t o Georgia in order t h a t t h e y might be representative of t h e turpentine produced t h r o u g h o u t this belt. T h e y were t a k e n from barrels .which were being filled a t t h e still or from those which h a d just been filled a n d rolled i n t o t h e storage shed. T w o lots were obtained, one in t h e fall of 1910a n d t h e other in t h e spring of 1911. F r o m each of t h e samples, as complete a history as possible was secured which covered t h e source of t h e g u m (whether dip or scrape, from boxes or cups, age of t h e faces, a n d other similar information) a n d t h e p a r t of distillation from which t h e sample was taken. A summarized description of t h e samples is given in Tables I a n d 11. As soon as t h e samples were collected t h e y were shipped in sealed, I-gallon tin cans t o t h e Forest P r o d ucts Laboratory. Analysis of t h e samples was begun a n d finished in such t i m e t h a t not more t h a n a m o n t h elapsed between t h e d a t e of collection a n d analysis. T o determine w h a t variation might be expected in
T H E J O T R N A L O F I N D C ' S T R I A L A N D E -VGI 9E E R I N G C H E M I S T R Y
J u l y , 1914
large lots of commercial oils, a sample was obtained a t monthly intervals from large stock t a n k s a t Pensacola.' For studying t h e effect of storage, t w o I-barrel samples of fresh turpentine were obtained2 a n d stored
of four months. virgin scrape.
543
T h e turpentine was distilled from METHOD O F ANALYSIS
The method of analysis, which consisted of fractional distillation a n d t h e determination of t h e physTABLEI-SPECIFIC GRAVITY, INDEX OF REFRACTION, A N D PERCENTAGES DISTILLIKG U P TO 165' ABD 170' OF TURPENTINES COI~LECTED ical properties of t h e fractions, is fully described in I N THE FALL OF 1910 Per cent Fovest Sevvice Bulletin 105.' T h e fractionating apRefrac. distillate Sp. gr. index to p a r a t u s consisted of a twelve-inch Hempel column at & at Part Samp. Kind Recep- Year of filled with glass beads. T h e sample consisted of 500 170' 15OC. 15OC. 165' taDnine of run S o of eum tacle _. 1130 Srrape Box 1st and 2nd Last 0.8683 grams of oil a n d t h e fractions collected amounted t o 1131 Scrane Box 1st Last 0.8704 1132 Scrape Box 4th All I O per cent except for t h e first j per cent of approximately 1133 Dip Box 1st First First 1134 Dip Box 4th distillate. For t h e first lot of samples ( S o s . 1130 t o First 1135 Dip Cup 1st and 2nd I 164, inclusive) about 2 per cent was taken for t h e first Last 1136 Dip Cup 1st and 2nd All 1137 Dip Cup 1st and 2nd fraction a n d t h e distillation was continued until a Last 1138 Scrane C & B 2nd 1139 Scrape Box 2nd Last 0.8686 temperature of I i o o was reached or t h e distillate Last 0.8678 1140 Scrane Box 5th 1141 Scrabe B ox l s t , 2nd and 5 t h Last ceased t o pass over. T h e other samples for which 1142 Scrape c u p 2nd Last 1143 Dip Box 2nd t o 5 t h Last detailed analyses are given (Nos. 1671 t o 1 7 o j ) were 1144 Scrape CUP 2nd Middle distilled in a slightly different manner. T h e first t w o c u p 1st 1146 Dip First 1147 Scrape Box 1st First fractions amounted t o about 2. j per cent each; t h e 1148 Dip First CUP 1st 1149 Scrane Box 4th and 5th Last specific gravity of t h e first fraction was taken sepa1150 Dip ' First CUP 1S t 1151 Scrape CUP 1 s t First rately; t h e n t h e t w o fractions were combined a n d t h e 1152 Scrape Box 2nd All Last 1153 Scrape Box 4th specific gravity of t h e mixture was determined. Also Box 4th and 5th 1154 Dip Last 1155 Dip All Box 1st and 2nd i t was aimed t o leave a residue of 5 . 0 per cent in t h e 1156 Dip Last Box 3rd distilling flask. These changes seemed advisable 1157 Dip Middle Box 1st and 2nd 1158 Dip First Box 2nd because of t h e great variations in t h e properties of 1161 Dip First Box 1st and 5 t h 1162 Scrape Box 5 t h First t h e first fraction when i t w a s as small as I . j t o 2 . o 1163 Dip First Box 3rd 1164 Dip CUP l s t , 2nd and 3rd Last per cent. Furthermore, when either t h e first frac______-0.8659 1.4721 8 7 . 0 9 3 . 0 M I N I M U M. .. . , . . . . . tion or residue is less t h a n j per cent, their specific 0.8704 1.4750 9 7 . 0 9 7 . 5 MAXIMUM . ... . . . . 0 . 8 6 8 0 1.4732 9 3 . 6 9 6 . 7 A V E R A G E. ,. .. . . . . . . gravities cannot be taken with t h e Westphal balance in general use in chemical laboratories, a n d when i t TABLE 11-SPECIFIC GRAVITI ., INDEX OF REFRACTION, A N D PERCENTAGES DISTILLINGUP TO 165' A N D 170' OF DIP TURPENTINES COLis a t t e m p t e d t o distil more t h a n 9 j per cent of t h e t u r LECTED I N THE SPRING OF 1911 pentine, polymerization takes place t o a considerable Per cent distillate t o extent; this has t h e effect of increasing unduly t h e Refrac. 165' or 170' or specific gravity a n d index of refraction of t h e residue. until until Kind of Sp. gr index Lab. recepPart at Year of at 5 Yc,re- 5 % reI
7 -
No. tacle 1671 Box 1672 Box 1673 Cup 1674 Cup 1676 Cup 1677 Box 1678 Cup 1679 Box 1680 Cup 1681 Box 1682 Box 1683 Box 1684 , . . 1685 Box 1686 Box 1687 Box 1688 B & C 1689 B & C 1690 B & C 1691 Box 1692 CUD 1693 B O X 1694 C & B 1695 C & B 1696 Box 1697 CUP 1698 c u p 1699 Box 1 700 Box 1701 Box 1702 Box 1703 Box 1704 Box 1705 Box 1706 Box
tapping 3rd 2nd 2nd 2nd 1st 1st and 2nd 1st 7th 2nd 2nd and 3rd 2nd 5th 2nd'to 1st 2nd t o 2nd t o 1st t o 2nd t o 1st
5th 5th 6th 6th 6th
I S t ~~~
hlIh-IMuhf.
.... . ., ,
AVBRAGI: .. ...
15O C. 0.8718 0,8696 0,8700 0.8674 0 8675 0 8704 0.8678 0,8703 0.8683 0,8722 0,8688 0.8688 0.8691 0.8707 0,8692 0,8694 0.8680
0,8678 0.8678 0.8668 First n. 86in -. First 0.8675 First 0.8675 Last 0,8668 Last 0.8719 Last 0.8690 Middle 0 8672 First 0.8697 Last 0.8713 Last 0.8688 First 0,8680 All 0.8696 First 0.8684 Last 0.8709 Last 0.8671 ~~
2nd 1st t o 5th 1st 7th 2nd and 3rd 1st 2nd and 4th 2 n d a n d 4th 2nd 5th 4th 4th 1st and 5th 1st and 5th
&f AXIMICM. .
of run Last First Last First All Middle First Last Last Last First All Whole Last Last First All Last Last Middle ~
0 8668 n 8722 n 8689
1 5 ' C. ,4733 ,4724 ,4745 ,4732 ,4722 ,4731 ,4724 ,4741 ,4731 ,4738 ,4725 ,4724 ,4726 ,4736 ,4729 ,4732 ,4722 ,4720 ,4722 ,4714 ,4714 ,4717
,4730 ,4730 ,4742 ,4745 ,4722 ,4740 ,4746 ,4744
,4731 ,4737 ,4734 ,4734 ,4724 1 4714
1 4746 i.4;30
mains 90.0 94.0 90.0 92.0 95.0 90.5 95.0 86.0 92.5 87.5 93.5 93.5 92.5 89.0 94.0
mains 94.5 95.0 94.5 95.0 95.0 94.5 95.0 93.0 94.5 94.0 95.0 94.5 94.5 93.5 94.5
95.0 94.5 94.5 95.5 95.0 94.5 91.5 88.0 86.0 87.5 93.5 89.5 87.0 86.5 90.5 90.5 92.0 92.0 93.0
95.0 94.5 95.5 95.5 95.0 94.5 93.5 94.0 93,5 94.0 94.5 93.5 94.0 94.5 95 . O 93.0 94.5 94.0 95.0
86.0 95.5 91 5
93.0 95.5 94.4
., ,.
....
a t t h e laboratory; these were examined a t intervals T h e American h-aval Stores Company, from m%om rhese samples Fere obtained, state t h a t turpentine is constantly added to and withdrawn from their tanks so t h a t the contents seldom remain undisturbed for a period longer than one week. 2 From Gillian. Vizard and Company, New Orleans, La.
ANALYSIS O F F R E S H L Y D I S T I L L E D O I L S
Table I gives t h e specific gravities, indices of refraction, a n d percentages distilling t o 165 o C. a n d I 7 0 ' C. for t h e dip a n d scrape turpentine collected in t h e fall of 1910; similar determinations on t h e turpentines collected in t h e spring of 1911 are given i n Table 11. T h e specific gravity of t h e turpentines ranged from 0 . 8 6 5 9 t o 0.8722, with an average of 0 . 8 6 8 j for all co'nditions of production. T h e index of refraction of t h e same samples ranged from 1.4714 to 1.4746, with a n average of 1,4730. T h e specific gravity values are fairly evenly distributed throughout t h e range indicated, except in t h e upper portion, where t h e y are more scattered. Boiliizg Point-The samples collected in t h e fall of 1910 had a r a n g e of boiling point of I j j " t o 1 j 7 . 6 " , t h e average being I j 6 . I '. T h e boiling points of the samples collected in t h e spring of 1911 ranged f r o m 1 j 4 . 1 O t o 1 j 6 . 9 ' , t h e average being I j j . 8 " . First Fvactioits atzd Residues-The first fraction amounting t o 2 . j per cent h a d t h e following properties: specific gravity a t I j ' 0,863-0.86 j j , t h e average being 0 . 8 6 4j ; refractive index I . 4674-1.4;08, t h e average being I , 4 6 9I . T h e first fraction amounting t o j.o per cent h a d t h e following properties: specific gravity 0.8641-0.8663, 1
"Wood Turpentines, Their Analysis, Refining, and Composition,"
by L . F . Hawley.
544
T H E J O U R N A L OF INDUSTRIAL AND ENGINEERING CHEMISTRY
t h e average being 0 . 8 6 5 2 ; refractive index I . 4691I . 4710,t h e average being I . 4698. As anticipated, t h e residues showed t h e greatest variation. T h e properties of t h e 5 per cent residues were as follows: specific gravity 0.8873-0.9723, t h e average being 0.9121;refractive index I ,4837-1. j 0 8 2 , ’ t h e average being 1.4920.
Vol. 6, N o . 7
from first- a n d second-year faces. T h e average for all samples of t h e former class is 0.8691,a n d of t h e latter 0.8678. T h e age of t h e face seems t o have little or no influence on t h e properties of turpentine distilled from scrape gum. Method of Collecting Gum-The turpentines from boxes have a n average specific gravity 0.0012 greater t h a n those from cups, b u t when individual samples are compared there is little regularity in t h e values. T h e average index of refraction a n d range of refractive values are practically identical for both classes ‘ o f turpentine. P a r t of Distillation-The p a r t of t h e distillation r u n from which t h e sample is t a k e n has a very evident influence on i t s specific gravity. T h e average gravity of all samples from t h e first p a r t of t h e r u n a n d of those representing t h e middle p a r t of t h e whole r u n is practically t h e same, b u t t h e samples from t h e last p a r t
EFFECT OF C O N D I T I ~ N S OF PRODUCTION O N PROPERTIES
Season of Year-The (‘dip’’ turpentines collected i n t h e spring h a d a n average specific gravity of 0.8689 while t h e specific gravity of those collected in t h e fall was 0.8676. T h e difference shown b y t h e average values appears fairly consistent in t h e individual Samples, notwithstanding t h a t t h e lower range is identical for both classes. Of t h e 35 samples collected in t h e spring, 19 h a d a specific gravity higher t h a n t h e average for all samples, while of t h e 1 7 dip turpentines collected in t h e fall only three fell above t h e mean value IO0
00
70 Y
3.0 a
EI50 $ & I
i
K&l 20
0
Is1
158 160 164 168 112 TLYPPRATURE IN DEGREES CENT.
FIG 1
1%
SPCCICIC QRAVITY
FIG
for all samples. T h e average index of refraction, as well as t h e range of refractive values is practically identical fo’r t h e two classes of turpentines. Kiwd of Gum-The samples collected in t h e fall of 1910included turpentines from both dip a n d scrape gums. T h e average specific gravity of t h e scrape turpentines was 0.8683 a n d of t h e dip turpentine 0 , 8 6 7 6 ; t h e maximum a n d minimum values were also higher for t h e scrape turpentines t h a n for t h e dip turpentines b y about t h e same a m o u n t as t h e average values. T h e average index of refraction for b o t h classes of turpentines was precisely t h e same, b u t t h e range for t h e scrape turpentines was a trifle narrower t h a n for t h e dip turpentines. T h e average specific gravity of t h e first fractions a n d t h e average values of both t h e specific gravity a n d index of refraction of t h e residues are slightly higher for t h e scrape t h a n for t h e g u m turpentines. A g e of Faces-The dip turpentinesfrom 3- t o 7-year faces h a d a slightly higher specific gravity t h a n those
2
RRCRACTIVE INDEX
FIG.3
of t h e r u n have higher gravity t h a n those from t h e first a n d middle. This variation is fairly consistent among t h e various classes of samples. T h e index of refraction of t h e samples from t h e last p a r t of t h e r u n is also higher.’ S u m m a r y - T u r p e n t i n e s v a r y in specific gravity with t h e conditions under which t h e y are produced. T h e average gravity is higher for scrape t h a n for dip turpentines, higher for turpentines collected i n t h e spring t h a n for those collected in t h e fall, higher for old faces t h a n for new, higher for boxes t h a n for cups, a n d higher during t h e last p a r t of t h e distillation r u n t h a n during t h e first part. These differences are very small; b u t t h a t t h e y are real a n d not accidental is in1 T h e barrel into which t h e water and oil ru’n from the still a n d where t h e separation of water a n d oil is effected, usually remains from one-half t o three-fourths full, t h e turpentine being gradually dipped out t o prevent overflow, consequenhy t h e samples are more uniform t h a n it would appear since a sample taken from t h e last third of t h e r u n is not taken from t h e l a s t third t h a t actually runs from t h e worm. Furthermore, since t h e turpentine is distilled in t h e presence of water vapor there would be no sharp separation into light a n d heavy fractions.
*
J u l y , 1914
T f€ E J 0 C R nT A L 0 F I N D C'S T RI A L A ND E N G I N E E RI N G C H E M I S T R Y
dicated b y t h e fact t h a t t h e variations are fairly consistent a m o n g individual samples, a n d t h a t t h e effects are most pronounced when several factors are combined. T h e highest average gravity for a n y group of samples occurs for three which come from t h e last p a r t of t h e r u n on g u m collected in t h e spring from old faces b y boxes; t h e lowest occurs for four samples from t h e first p a r t of t h e r u n on g u m collected in t h e fall from first- a n d second-year faces, b y cups T h e index of refraction varies t o some extent for t h e individual samples, b u t t h e average values for t h e different classes are practically t h e same. Although t h e physical properties of turpentine v a r y with t h e conditions of production, t h e variations are comparatively small a n d t h e range of values for normal turpentines is likewise comparatively small. T h e range for percentage distillation a n d specific gravity a n d index of refraction of gormal g u m t u r p e n tines 15 shown graphically in Figs. I , 2 a n d 3. These curves show t h e extreme limit of physical properties for authentic samples.
TABLE 111-ANALYSES Date Lab. received No. 1912 1967 Jan. 2216 Feb. March 2230 April 2315 2115 May June 2170 2207 July 2417 Aug. 2447 Sept. 2501 Nov. sov. 2546 Dec. 2594
OF
8
4 19 14
545
TURPENTINES OBTAINED A T MONTHLY INTERVALS FROM STORAGE TANKS Date examined 1912 Jan. 25 Feb. 20 March 8 April 10 7 May 10 June 10 July 8 Aug. IO Sept. 7 Nov. Nov. 22 Dec. 17
S p . gr. at 15OC. 0.8696
0.8688 0,8687 0.8685 0.8683
Ind. of ref. a t 15OC. 1,4726 1,4726 1,4725 1,4726 1,4726 1.4728 1.472: 1.472; 1.4729 1.4730 1.4730 1.4729
95 per cent distilled up t o o
c
167.5 166.5 166.0 167.5 167..5 167.0 167.0 167.0 167.0 166.5 166.0 166.5
tive index, I 4 7 2 7 , of these samples agree well with t h e corresponding average values for t h e samples examined in t h e preceding series of tests, namely, 0.8685 a n d 1.4730. T h e ranges for percentage distillation, specific gravity, a n d refractive index for t h e samples obtained from stock t a n k s are given in Fig. 4, a n d are much narrower t h a n those given in Figs. I , 2 a n d 3. This greater uniformity is t o be expected i n t h e samples t a k e n from bulk quantities. Since it is not known what class of turpentine predominated i n a t a n k a t a n y time, such variations in physical properties as appear cannot be fully explained. However, t h e higher specific gravity of t h e samples t a k e n t h e first months of t h e yea? m a y be accounted for since t h e first dipping of t h e season is not distilled until April or M a y , a n d scrape turpentines from t h e previous season would predominate during t h e winter months. E F F E C T OF STORAGE
T h e t w o barrels of turpentine secured for storage a t t h e Forest Products Laboratory were distilled t h e middle of December, 1910. Sample No. 1559 was stored i n a n iron d r u m , while K O . 1560 was left i n t h e original. container. Both samples were first examined March 30, 1911,a t which t i m e sample KO. 1559 was transferred t o t h e iron d r u m , a n d were subsequently examined at periods of approximately four months each. T h e results of examination are given in Tables I V a n d V. Sample N o . 1559 shows b u t a slight change after storing for 1'/3 years, while t h e specific gravity of
5
g L
I
TABLE I\'-sUCCESSIvE D a t e of examination March 30, 1911 July 26, 1911 December 6, 19 11 April 4, 1912 August 8, 1912
.4NAI,YSES O F
TURPENTIUE STORED I N
IROI.:
DRUM
(SAMPLEN o . 1559) Age Months 3'12 7'/2
111 1 2 15 I/? 19'/*
Specific gravity a t 15'C. 0.8685(a) 0.8682 0.8681 0.8684 0.8688
Refractive index a t 15'C.
....
1.4723 I ,4723 1 ,4724 1,4724
N o . 1j60 has increased b u t o . o o a j during t h e same period. T h e l a t t e r sample h a d t o be frequently transferred from one barrel t o another because of leakage a n d was more exposed t o t h e air t h a n t h e sample in t h e iron d r u m which mas practically air-tight. ANALYSESOF TIJRPENTIXE STORED I N %'OODZN BARREL(SAMPLEKO. 1.560) Specific D a t e of Age gravity Refractivz index examination Months at 15OC. a t 1 5 C. March 30. 1911 3 112 0.8682(a) .... n ,8680 1.4719 7'/2 July 26, 1911 0.8681 1.471Y December 6, 1911 1 I '/z 0.8691 1.4721 15 1;'2 April 4, 1912 1 ,4724 19'12 0.8715 August 8, 1912 (a) A Westphal balance was used for determining t h e specific gravities on March 30, 1911, while t h e succeeding determinations were made with a Gay-Lussac pyknometer t o secure greater accuracy. This accounts for t h e higher specific gravity of t h e first determinations. T A B L E V-SUCCESSIVE
IS1
110
RS
110 l ? ~ - l C ~ ~ C R A T U ~ ~ KAR - D ~ ~ ~ t S .w1 JW .ME .am m -SPCCIFIC ORAVITY IYDCX O? R C I R A C T I O Y - I M U I IAm I.4n U7 14%
A10
FIG 4 A i S A L Y S E S OF S A M P L E S F R O M S T O C K T A K K S
T h e analyses obtained at monthly intervals from stock t a n k s a r e given in Table 111. T h e average specific gravity, 0.8689, a n d refrac-
I
546
T H E J O U R N A L O F I N D U S T R I A L A N D ENGINEERIAVG C H E M I S T R Y
V O ~6, . NO. 7
T h e extent t o which sample No. 1559 h a d changed is shown i n Fig. 5 , where t h e distillation d a t a obtained on December 6, 1911, before a n y appreciable change in specific gravity occurred, are compared with t h e last distillation made (August 8, 1912). Coincid e n t with t h e change i n specific gravity there is a slight increase in t h e a m o u n t of high boiling constituents a n d a n increase in t h e index of refraction of these constituents.
terpenes. T o examine t h i s point further, a three-liter green glass bottle with a narrow neck was filled t o within one-half liter of i t s capacity with turpentine from t h e same barrel a n d allowed t o s t a n d open t o t h e atmosphere i n t h e laboratory. T h e average t e m perature was about zoo Centigrade. T h e exposure lasted from October 2 3 , 1912, t o February j , 1913, approximately 3l/2 months. T h e specific gravity of t h e oil when set o u t for exposure was 0 . 8 7 2 j a n d a t
Fig. 6 shows t h e change t h a t took place in sample T h e original specific gravity h a d changed 0.0034 a n d a considerable increase i n high boiling constituents was anticipated. It will be noted, moreover, t h a t t h e boiling point, index of refraction, a n d specific g r a r i t y show a decrease i n t h e lower p a r t of t h e curves; t h e difference is especially large for t h e specific gravity. T h e boiling point of t h e last fraction could not be accurately determined, since t h e mercury continued t o drop gradually, although t h e distillate came over regularly. An explanation t h a t m a y be offered for t h e changes occurring in this sample is t h a t a selective oxidation h a d t a k e n place a t t h e expense of t h e higher boiling
t h e end of t h e test 0 . 8 8 4 8 , t h e index of refraction being 1.4746. T h e curves obtained on distilling 500 grams of t h e aged oil are compared i n Fig. 7 with t h e curves obtained December 6, 1911. T h e original oil showed no turbidity a n d no apparent change in color b y aging. T h e initial boiling point of t h e oil after exposure was a b o u t 1 4 j 0 C . , a n d upon distillation I O per cent. o f water was collected in t h e first fraction. T h e a m o u n t of water present in t h e distillate decreased gradually t o fraction No. 6-the only clear fraction obtained-and increased from this point t o t h e end of t h e distillation. I n t h e case of fraction No. 9 , t h e temperature dropped gradually t o 1 3 s 0 , t h e oil distilling regularly until this temperature was
KO. I j60 during t h e same length of time.
July, 1914
T H E J O U R N A L OF IiVDrSTRIAL A N D ENGINEERING CHEMISTRY
reached, when distillation ceased. Parallel distillations were r u n a n d i t was found t o be impossible t o prevent t h e drop i n temperature a t this point, even b y doubling t h e r a t e of distillation. Nearly t h e full power of t h e Bunsen burner was required t o obtain fraction No. IO, amounting t o 1 . 9 5 per cent a n d containing a b o u t I O per cent water. T h e residue amounted t o 1 2 . 3 per cent with a refractive index I . 5 2 6 j a n d a
54 7
were combined a n d allowed t o s t a n d twelve hours. Considerable water a n d a yellow sediment deposited. T h e layer of turpentine was decanted off clear a n d shaken with anhydrous sodium sulfate a n d 500 grams were t a k e n for distillation. T h e results of this distillation are again compared with t h e original turpentine i n Fig. 8. There is a noticeable decrease in boiling point a n d refractive index, a n d especially in specific gravity. F r o m our present knomledge, a-pinene, camphene, a n d P-pinene are t o be considered t h e chief terpenes present in g u m turpentine. a-Pinene has a specific gravity of about 0 . 8 6 3 a t 15 O a n d boils a t 156' Centigrade. Camphene has a specific gravity of a b o u t 0.87oandboilingpoint 160°, b u t i t is one of t h e most stable of t h e terpenes towards air and light. &pinene has a specific gravity of about 0.868 a n d a boiling p o i n t o f 164-166'. A greater oxidation of t h e 6-pinene i n preference t o t h e a-pinene would account for t h e decrease in t h e values for t h e physical properties of t h e fractions. CONCLUSIONS
I-There is a tendency for t h e specific gravity t o be higher for scrape t h a n for dip turpentines, higher for turpentines collected in t h e spring t h a n for those collected in t h e fall, higher f o r old faces t h a n for new, higher for boxes t h a n for cups, a n d higher for t h e last p a r t of t h e run t h a n for t h e first. However, t h e differences between t h e turpentines f r o m these various sources are slight. 11-The properties of bulk quantities composed of 862 .BS4 ,866 .S68 .a70 .872-SPEClFlC PRAVITV INDEX OF REFRACTION-IMB 1470 ~AZI 1474 i4m i4m IRED IS turpentines produced under FIG. i various conditions should specific gravity of 0 . 9 9 3 a t 2j0. T h e low boiling approach t h e average values given below. points of several of t h e fractions m u s t be due t o steam 111-Turpentine stored with reasonable care for a distillation caused b y t h e presence of water. T h e ' period of one year will show little or no change in water doubtless results from t h e breaking u p , on heat- physical properties. ing, of t h e hydrates formed b y aging. IT-Aged turpentines will contain varying amounts Owing t o t h e presence of water, t h e distillation of , of oxidation products of t h e terpenes, depending upon t h e oil altered b y age did n o t give satisfactory informa- t h e degree of aging or exposure a n d should not be tion in regard t o t h e changes which m a y have t a k e n considered normal turpentines. place in certain of t h e constituents. Accordingly, T-The range a n d average values for t h e physical t h e first nine fracticns of t h e two parallel distillations properties of normal, freshly-distilled, gum turpen-
T H E J O U R N A L O F I N D U S T R I A L AhTD E N G I N E E R I N G C H E M I S T R Y
54.8
Vol. 6, KO. 7
tines, based on t h e analysis of 67 samples, are a s fol- increase in specific gravity. I n no case should t h e lows: specific gravity of a n y fraction be lower t h a n t h a t I-The specific gravity a t I j o C. will fall between of t h e previous fraction. 0.8659 a n d 0 . 8 7 2 2 , with a n average of 0.8685. T h e FORESTPRODUCTS LABORATORY FORESTSERVICE, u. s. DEPARTXENT OF AGRICULTURE index of refraction a t 1 5 " C. will fall between 1.4714 (In Cooperation with the University of Wisconsin) a n d 1.4746, with a n average of 1.4730. T h e initial MADISON boiling point will n o t be lower t h a n I 54" or higher t h a n 157,6",a n d will average about I j6'. THE HYPOCHLORITE OF LIME TREATMENT OF A MUNICIPAL WATER SUPPLY AND A STUDY OF CERTAIN RESISTANT BACTERIA By STANLEY JUDSONTHOXAS Received April 9, 1914
IN T R 0 D U C T I 0 N A ND HIS T 0 R Y
On March
.W
368 J6D .87O-lPTCIFIC PRAVITY INDEX Or RWR4CTIOW-1.466 1.470 1.472 lA74
1.471
1478
FIG 8
2-The first fraction b y t h e method of distillation used, amounting t o 2 . 5 per cent, will have a specific gravity not lower t h a n 0.8630, a n d will average a b o u t 0.8640; t h e index of refraction will be not lower t h a n 1.4675 a n d will average about 1.4690. If t h e first fraction amounts t o j per cent, t h e specific gravity will be n o t lower t h a n 0.8640, with a n average of 0.8650; t h e index of refraction will be not lower t h a n 1.4690, with a n average of 1.4700. 3-At least 86 per cent, generally 91-93 per cent, will distil u p t o 16 j '; a n d a t least 93 per cent, generally 97 per cent, will distil up t o 170'. 4-The residue of 5 per cent will have a specific gravity n o t lower t h a n 0 . 8 8 7 j a n d i t will average a b o u t 0.9140. T h e last fractions should show a s t e a d y
2 7 , 1909, t h e Council of t h e City of Bethlehem, Pa., passed a n ordinance appointing a committee t o investigate conditions a n d decide upon a site for a new water supply for t h e city. This was t h e first official act t a k e n t h a t contradicted t h e idea t h a t Bethlehem was being supplied with pure water. Until a few m o n t h s previous t h e city was supposed t o have one of t h e best water supplies i n t h e State of Pennsylvania. While t h e cistern has been more or less i n vogue in this community always, yet as a municipality Bethlehem m a y be said t o have probably t h e oldest public water system i n t h e United States. T h e old pumping station back of t h e Eagle Hotel is a n historic landmark, ranking in age with t h e Moravian Chapel a n d some of t h e rest of t h e city's pre-Revolutionary buildings. When one considers t h e length of t i m e t h a t this source has supplied t h e city with water, it can readily be seen how some of t h e citizens objected t o a seemingly enormous outlay of money for a new supply. On July t h e fourteenth, 1909, Council authorized t h e purchase of Illick's Mill site a n d gave permission t o t h e committee t o spend t h e necessary money for drilling wells. A bond issue was then placcd before t h e people a n d in t h e fall of t h a t year i t was passed. There were objections raised, however, a n d t h e case was t a k e n t o t h e Supreme Court. T h e Court decided t h a t t h e ballot h a d been defective a n d t h a t t h e bond issue was defeated. Work on t h e Illick's Mill plant was necessarily suspended a n d Bethlehem saw no chance for a change in water supply. T h e city h a d grown enormously in t h e last decade in t h e vicinity of t h e old spring a n d i t was well known t h a t t h e water was badly contaminated. T h e spring a n d well were down in a hollow surrounded b y buildings. Theoretically, one could not look for a worse place from which t o draw a public water supply. Practically, t h e water was being polluted as badly as could be conceived of. It might be well t o s t a t e here just what constitutes a "good" water supply a n d wherein t h e Bethlehem water failed t o fulfill t h e requirements Savage (Savage-Water Supplies, page 2 ) classifies bacteria found in water into three divisions. I-Normal inhabitants, as B . jluorescens liqzLi,facie%s. This class comprises all bacteria which find water a suitable medium for their growth a n d multiplication. This class m a y be present in large numbers without necessarily indicating contamination. I t would mean,
