Sulfur Dioxide in Air of Industrial Community C. E. BETZ,J. H. HOLDEN, AND J. 0. HANDY, Pittsburgh Testing Laboratory, Pittsburgh, Pa.
T
HE atmosphere in every days, two tests on 222 days, The concentrafion of sulfur dioxide in the air industrial community, and three or more on 19 days. of a typical industrial community in Pitlsburgh, especially in 1o c a1i ti e s At the time of the test, the 75 feet above the ground, has been determined where bituminous coal is largely wind direction was noted and obover a period of one year; 607 tests on 307 days servations as to v i s i b i l i t y , by used a s f u e l , is contaminated were made. An average of 0.3 p . p . m. .for all with sulfur dioxide to some desighting on three points, were made. The latter observations gree. In order to determine the tests was obtained for the year, the higher conextent of this contamination in were made for the purpose of centrations occurring in the morning hours obtaining a r e l a t i v e value for Pittsburgh, daily tests for sulfur when a n average of 0.38 p . p . m. was f o u n d as the amount and intensity of the dioxide were made for one year against 0.19 for the afternoon hours. The maxifog and smoke often present in on the roof of the l a b o r a t o r y m u m sulfur dioxide concentration f o u n d was downtown Pittsburgh. Actual building. This building is apw i n d directions a n d velocities proximately one-half mile from 2.5 p . p . m. were o b t a i n e d from the U. S. the b u s i n e s s district of PittsHigh sulfur dioxide readings were invariably Weather Bureau, Pittsburgh. burgh, in a rather thickly popuobtained with low wind velocities and especially lated section. Within a radius RESULTS OF TESTS when fog and smoke accompanied them. of a city block are t w o l a r g e Table I shows a distribution garages, a large dairy products plant, a school, a hospital, and a small manufacturing plant, summary of all tests run throughout the year. Table I1 constituting a typical district in an industrial community. shows a similar summary for the morning tests, and Table The testing station was approximately 75 feet above the I11 for the afternoon tests. The concentration of sulfur dioxide for the period of one ground. Each test was taken on the windward edge. The Bureau of Mines, in 1928, made a similar survey in year varied from 0 to 2.5 p. p. m. by volume. On only 58 Pittsburgh (3) but a t a greater elevation and distance from days (or 18.9 per cent of the year) was the atmosphere free or the center of the city and in a much less thickly populated nearly free of sulfur dioxide. The concentration of sulfur section, although in that case the smoke from a nearby rail- dioxide varied from 0.1 to 0.5 p. p. m. on 185 days (60.3 per road was a factor which does not enter directly in the present cent), from 0.5 to 1.0 p.p.m. on36 days (11.8 per cent), and survey. The Bureau of Mines report, however, was made a t above 1.0 p. p. m. on 28 days (9.0 per cent of the total time). a time when the industrial activity in the Pittsburgh area The maximum amount found, 2.5 p.p.m., occurred on two was a t its height. The present report deals with a period, different mornings, October 19 and 23, when there was a 1931-2, when industrial activity was far below its peak and on heavy blanket of fog and smoke with little or no wind velocity. a gradual decline. The method used for the determination of The average concentration for the year was 0.30 p. p. m. Tables I1 and I11 show that the highest concentrations of sulfur dioxide was that developed by the Selby Smelter Commission (1) and later modified by McKay and Ackerman sulfur dioxide in the atmosphere occurred in the morning hours; 24.4 per cent of the mornings as against 36.8 per cent (2). A t least two tests were made on each working day of the afternoons showed the atmosphere to be practically throughout the year, one a t approximately 9 A . M. and the free of sulfur dioxide, The maximum sulfur dioxide content other as near 3 P. M. as possible. KO afternoon tests were for the year, 2.5 p. p. m., occurred in the morning as against a m a x i m u m of 1.6 made on Saturdays. 1 9 3 1 p. p. m. on the afterOn days w h e n t h e noon of July 3, 1931. c o n c e n t r a t i o n of F e b r u a r y , March, sulfur d i o x i d e was and J u n e w e r e the one part per million only months in which by volume or m o r e , the maximum succeeding tests were amount of sulfur dirun a t i n t e r v a l s of oxide in the morning 3 10 t o 15 m i n u t e s was less t h a n one until the concentrap. p. m., whereas only tion fell to less than I July, December, o n e p. p. m. T h i s .? J a n u a r y , and June procedure was carried showed a maximum of out in the majority over one p. p. m. for of c a s e s . A t o t a l the afternoon tests. of 607 t e s t s w a s The average for the made on 307 days beyear in the morning ginning July l, 1931, h o u r s w a s 0.38 .... or vine* R ~ O U and ending June 30, p.p.m., and 0.19 in 1932. One test only FIGURE1. AVER.4CE SULFUR DIOXIDECONCEIVTRATION FOR EACHW E E K the afternoon. OF SURVEY w a s m a d e o n 66 7 74
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 hl I S T R Y
J u l y , 1933
TABLEI. -DAYS MOXTA
0.1
0.2
0.3
0.4
4 9 9
2 1 3
3 5 5
3 4 .
6 2 1
4
5
1
1
1
1
3 5 9
2 2 2
1 12 11 3 8 5
4 3 4 3 9 2
2 1 3 2 1 7
26 26 25
Oct. Nov. Der.
27 24 26
50 43 55
,.
..
2
Jan. Feb. Mar April Xay June
25 25 27 26 25 25
43 46 47 49 46 43
5 5 5 7 4 6
3 4
of time
1
5 1 3
-
-
-
607
58
31
56
...
18.9
-
.-
307
...
SUMMARY O F
.
0.6
0.6
0.7
0.8
0.9
1.0
.
1 1
, 1
1
1
l
.
.
.
1 1 0 . 3 7 2 . 3 3 . 0.28 1.8 4 . 0 . 2 2 1 . 6
.
3
1 z .
3
1 1 1
3 3 0.44 2.5 3 . 0.46 2.0 3 . 0 . 5 1 1 . 5
.
2
2 . 0 . 3 7 1 . 5 . 0.12 0.4 . 0.18 0.8 . 0.24 1.8 , 0.22 1.4 . 0.21 1.3
3
1
.
'
.
i
1932 1 3
.. . .
-
-
49
31
18
8
.
1
. . . . . . . 1 . 2 . . . . . . . . 2 .-. -1 . . - . - . -. -1 1 3
.
1
1
11
.
6
. .
.
5
6
24
TESTS 0 . 0
0.1
0.2
io
2 1 3
6
5
5
A.
0.4
0.5
5
1 . 1
0.6
0.8 0 . 9
0.7
1.0
1.1- Over 2.0 2.0
1931 4 9
July Aug. Sept.
26 26 25
27 69 25
Oct.
27 24 26
28 24 35
Nov. Dec. Jan. Feb. Mar April May June Total
,.
3 5
.
1
3
6 8 9 12 4 7
1 2 11 9 3 8 6
2
.
. . . .
2 3 1
-
._
-
-
-
-
-
.. .. -
307
368
75
34
55
44
28
11
.. ,
3
..
.
1
.
..
1 2
1 1
,
1 3
,
. .
.
1932 1 3
1
1
2
i
1
2
24.4 Maximum occurred on eight different days.
2
3 4
2 2
% of time a
5
4 5 9
.
1
1
3
.. ..
TEST8
3
so2
sw
1 :3
1 1 1
3 3 3
3
0.74 0.63 0.60
2.5 2.0 1.5
E E
4 4
..
2
.. ..
4
-
-
-
-
11
7
5
4
22
'
0.0
0.1
0.2
0.3
0.4
3 2
4
0.5
8.5
P. M . )
2 . 0 2.0
SO1 WIND Av. Max. Direction Velocity P. p . nr. P. p . in. M. p . h.
.
.
.
.
.
.
.
0.20
0.5
3
.
.
.
.
.
.
.
.
.
0.25
0.5
2
. . . . .
1
22
22
7
3
5
2
3
2
Nov
19
19
2
1
6
6
1
19
20
1
5
4
5
1
.
1.1- Over 1.0
.
Oct.
.
0.9
.
..
1
1931 1
0.8
1.6 0.3 0.4
7 2 4
.
0.7
0.6
0.30 0.07 0.08
3 4 3
.
.
.
.
.
1
1
0.36
1.0
. . . . . . . . . . . . . . . .
2
0.26
1.0
0.10
0.3
0.16 0.16 0.12 0.20
0.5 0.8 0.4 1.3
1932
21
21
Mar. April May June
20 20 18 17
20 20 18 18
Total
7'
of time
6
8 10 5 6
-
11.1
. . . . . . 1 . . . . . . . . . . . . . . . . .
3 12 13
Feb.
1
DAYSAT FOLLOWINQ Max. CONCN. O F S O I (P. P. Y. B Y VOL.):-
23 20 21
17
4
,
1.5 0.4 0.8 1.8 1.4 0.4
2 2
7
23 20 21
16
N
Velocity M . p . h.
2.3 1.8 1.6
1
. A
WISD
Av. Max. Direction P . p . m. P. p . m. 0.42 0.32 0.34
-
July Aug. Sept.
Jan.
SW N
. .
TABLE111. SCXMARY OF AFTERNOON TESTS(12 to 5 -c
1 1 0 , ~ ~ D~A Y S
SE
1
.. -
.
5 8 10 5 6 18
'3 4
8
56.0
NE N E
i .
3
.. 1 ..
E E
M.)
FOLLORINQ MAX. CONCN.OF SO2 (P. P. M . BY VOL.):0.3
{ NSSE
9.0
TESTS(8 to 12
MORNINQ
1 3 4 1 2 4 4
4
11.8
TABLE11. SUMMARY OF
-
N
SW
LC_
__.A
AT
SO2 WIND Av. Max. Direction Velocity M . p . h. P . p . m. P.p . m.
1931 2 2
4 5 2
.
1.1- Over 2.0 2.0
1
. . . . . .
60.3
-DAYS
MOXTH DAY6
TESTSFOR YE.4R
FOLLOWINQ MAX. CONCN.O F SO2 (P. P. M. BY VOL.)-:
TESTS 0 . 0
July Aug. Sept.
Total
7 '
AT
175
5 1
1 0
3 3
3 6
2
1
1
. .
.
1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
236
239
87
30
52
33 -59.4
14
12
2
,
1
1
3
1-
1
36.8
Figure 1 shows graphically the average sulfur dioxide concentration for each week throughout the survey. Curve 1 gives the fluctuation in the morning tests, each point representing the average of all of the tests taken between 9 A . M . and 12 BI. during each week. Curve 2 shows in the same manner the weekly average of the afternoon tests. Curve 3 is the weekly average of all the tests taken during each meek. For curve 4, the monthly averages obtained during the present survey are compared with the monthly averages shown in the Bureau of Mines Report (3). Each of the curves shows an increase in sulfur dioxide concentration during Oc-
..
N
NE
I,
SW
10 12
k
9 14 3
1;/' S E Stv { SE
16
{E
8 8
{+ NE E
N
4
8
11
9
A
15 18
v
3.0
0.8
tober. The Bureau of Mines reports a decrease in Xovember and December, while the present survey shows a gradual increase through December, owing, no doubt, to the greater effect of domestic heating plants in a more thickly populated section. As a typical example of the rate of disappearance of sulfur dioxide when foggy conditions prevailed, Table IV shows the results of tests taken on August 6, 1931. The worst conditions, however, came on December 28,1931, when a concentration of over 0.5 p. p. m. was found during the entire day. Tests mere not run during 4 hours in the afternoon. Table V gives in detail the tests made.
INDUSTRIAL AND ENGINEERING CHEMISTRY
776
TABLEIV. RATEOF DISAPPEARANCE OF SULFUR DIOXIDEIN FOQ TIME
WIND Direction Velocity M . p . h. SW 3
(A. M.)
9:35 9:55 10:15 10:30 10:40 Visibility: 8
A.
SO1
FOQ
P . P. m.
1.8 1.8 1.1 0.9 0.5 M., '/a mile; noon, 1 mile.
Heavy Heavy Heavy Clearing
.....
RELATIVE TEMP. HUMIDITY O F .
% ,-
84
90
86
TABLEV. TESTSON DAYOF WORSTCONDITIONS~ TIME 9:15 A . M. 9:30 9:40 9:50 10:20 11:oo
WIND Direction Velocity M . p . h.
E
1.5
1.0 0.8 0.8 0.8 1.0
1/x
FOQ
Heavy Heavy Heavy Heavy 2 Heavy Clearing slightly 3 0.8 Clearing 4 1.0 Cloudy 0.8 Light rain mile; noon, 1 mile.
4
SE
11:40 sw 4:05 P . M . sw 4:35 Visibility: 8 A. M.,
SO2 P . p . m.
RELATIVE TEMP.HUMIDITY O F .
41
% 58
42 43
69
hospital and school which are located in an easterly direction approximately one block away from the testing station. On the other hand, the maximum sulfiir dioxide concentration for the year, 2.5 p. p. m., was obtained on two different mornings, October 19 and 23, the first with a south wind and the second with a northeast wind, indicating that the local conditions directly east of the testing station were not wholly responsible for high sulfur dioxide readings. The dairy plant in a northerly direction is a large consumer of coal, while the garages in northerly and westerly directions and the small manufacturing plant in a northerly direction do not require large heating plants. Naturally smoke from all these stacks influences the condition of the atmosphere, as do also the hundreds of smaller stacks from domestic heating plants. Smoke conditions over the testing station are considered typical rather than special, as regards the influence of purely local or adjacent sources of contamination.
45
The wind direction seemed to bear only a slight relationship to the high concentrations of sulfur dioxide. In many instances, high results were obtained with an easterly wind, influenced, no doubt, by the smoke from the power plants of the
Vol. 25, No. 7
LITERATURE CITED (1) Holmes, Franklin, and Gould, Bur. Mines, Bull. 98, 200-4 (1916). 20,538-42 (1928). (2) McKay and Ackerman, IND. ENG.CHEM., (3) Meiter and Traubert, Bur. Mines, Repts. Investigations 3005 (1930). RECEIVEDJanuary 4, 1933. J. 0.Handy's present address is 50 East Forty-first Street, New York, N . Y.
Thermal Expansion of Heat-Resisting Iron Alloys Iron-Chromium and Iron-Chromium-Nickel J. B. AUSTIN AND R. H. H. PIERCE,JR.,United States Steel Corporation, Kearny, N. J.
T
HE data hitherto availMeasurements have been made of the linear mercial low-carbon iron-chromium-nickel alloys containing able on the thermal exthermal expansion of commercial, rather low25 and 12, 18 and 8, and 18 and pansion of heat-resisting carbon, iron-chromium alloys containing approxi12 per cent of c h r o m i u m and a 11o y s of t h e iron-chromium and iron-chromium-nickel series matelY 1, 59 17, and 27 Per cent chromium, nickel, respectively; the remaining alloys were: an 18-8 stabirespectively, and on iron-chromium-nickel alloys have been well reviewed in a recontaining 18-8, 18-12, and 25-12 per cent of lized with titanium, a severely cent paper by Hidnert ( 3 ) . His cold-worked 18-8, a regular 18-8 survey shows that, while most of chromium and nickel, respectively. Data on the which had been in service in an the commercially i m p o r t a n t expansion of stabilized (titanium-bearing) 18-8, oil still for Over 8ooo hours, a n d alloys have been a d e q u a t e l y a cold-worked 18-89 a 25-12 alloy with per studied, there yet remain a few a 25-12 containing 2 p e r c e n t cent manganese, and a mild-carbon steel are manganese. Data on a m i l d for which the data are unsatisfactory. In one or two cases included. The expansion of ferritic alloys carbon steel have also been inappears to be lower than that austenitic cluded for comparison. Table I the several results on alloys of gives the exact chemical componearly the same composition are alloys. sition of these alloys as well as not in good agreement, probably a brief description of the heat because of small but frequently important differences in working or in heat treatment of the treatment when known. It is perhaps worth noting that, particular specimens examined; for certain other alloys aside from the carbon steel and samples 75A, 69A, and 5215, which are rapidly becoming of importance, there appear the carbon content is in all cases 0.10 per cent or less. to be no measurements a t all. Inasmuch as nearly all of MEASUREMENT OB EXPANSION these alloys are being extensively employed as materials The measurements were made by the Fizeau interference of construction in apparatus used a t high temperatures, it is desirable that more reliable values of the expansion coefficient method using an apparatus which enables the heating to be be available, and it has been considered worth while here to carried out in uacuo. In this method three small pins (apreport some new measurements on several of the most com- proximately 5 mm. in height and 3 mm. in diameter) of the metal to be investigated are used as separators for two monly used alloys. In all, eleven alloys were investigated. Four of these were polished fused-silica plates which form the interferometer. iron-chromium alloys containing approximately 1, 5, 17, A beam of monochromatic Iight is directed almost perpenand 27 per cent chromium, respectively; three were com- dicularly on the upper plate a t the second surface of which
