708
INDUSTRIAL A,VD ENGINEERING CHEMISTRY
Vol. 22, Xo. 7
Heat Transmission in an Experimental Inclined= Tube Evaporator"' C. hl. Linden3 and G. H. Montillon4 DEPARTMENT OF CHEMICAL
E N G I K E E R I N G , U N I V E R S I T Y OF M I N N E S O T A , b f I N K E A P O I , I S , b f I N N .
The work described in this paper was carried out on a nection to the flanges a t the H I L E many heatsmall inclined-tube evaporator, with one heating tube end of the steam space was transfer data have of I-inch copper pipe about 4 feet long. The evaporator made with suitable stuffing been o b t a i n e d o n was constructed so that the velocity of flow of liquid in boxes. horizontal and vertical evapothe downtake pipe could be measured. Runs were The vapor space, which was rators, particularly by Badger made with distilled water boiling at M O O , 195", and 3.5 feet long, contained an (1, 2, 4,) and his associates, 210" F. By means of suitable thermocouples vapor e n t r a i n m e n t separator 2.0 little has been published on and pipe temperatures were measured at temperature feet above the steam chest. the operating characteristics differences varying from 8" to 28" F. for each temperaThis separator was made of of the inclined-tube evapoture of evaporation. From the readings of velocity of a cylinder of galvanized iron rator. Van Marle (7) has flow of water, of vapor and pipe temperatures, and about 3 inches in diameter, published some results on weight of condensed vapor evaporated, the over-all and closed at one end with 0.75this type of evaporator, in individual heat-transfer coefficients were calculated. i n c h o p e n i n g s around its which he shows that the overThe Coefficients on the liquid side were found to inupper end. The lower part all coefficients on distilled crease with the temperature difference at any given of the cylinder contained a water boiling a t 138" to 143' temperature of evaporation. The logarithmic mean copper drain tube leading F. increase from 835 B. t. u. velocity of circulation of liquid plus vapor also varies below the normal liquid level. per square foot per hour per with the temperature difference, so that the liquid I t is seen that the water and degree Fahrenheit, a t 50" F. vapor coming from the heatcoefficients bear a definite relation to the velocities t e m p e r a t u r e difference, to ing tube would strike the flnt of circulation. The over-all coefficients were found to 1140 at 81" F. temperature end of the separator and be increase with the temperature of evaporation and with difference. Van Marle has sprayed to the sides of the the temperature difference. g i v e n o v e r - a l l coefficients vapor mace. The vapor then only, and his data cover a would pass around the cylinder making a 180-degree turn limited range of temperatures of evaporat'ion. It was decided to construct a single tube apparatus, in which before passing through the small openings. This action conditions could be quite carefully controlled, in order to would throw out the bulk of the liquid a t this point. Any make a preliminary study of t,he inclined-tube evaporator. liquid which may have been carried along with the vapor A small evaporator was built of wrought-iron pipe and fit'tings, would tend to separate out after passing through the small with one copper heating tube about 4 feet long. (Figure 1) openings and pass down the copper drain tube to the liquor This apparatus was fitted with the necessary condensers and space. The vapor now enters the upper part of the vapor condensate receivers, together with a series of thermocouples, space, which is 4.0 inches in diameter. The velocity in this so that data could be obtained to calculate the individual space a t the highest rates of evaporation used was only film coefficients. Further, it was planned to try to measure 3.0 to 3.5 feet per second, so that it seems reasonable to supthe flow of liquid in the downtake pipe, in order to find out pose that a minimum of entrained liquid would be carried the dependence of the heat-transfer coefficient on the liquid along with the vapor by such an arrangement. From the vapor space a 2.0-inch pipe led to a condenser and side upon the velocit,! of flow of fluid. condensate receiver equipped with a sight glass and a merApparatus cury manometer. d glass gage (not shown) indicated the height of liquid in the evaporator. The evaporator, which was inclined at an angle of 45 deThe 2-inch downtake pipe extended vertically downward grees, cont'ained a steam chest and liquor and vapor spaces and then made a 90-degree bend to lead to the lower part of all made of 4-inch wrought-iron pipe with flanged ends. The the liquor space. A 2-inch pipe was used t o cut down friction heating surface consisted of one 1-inch copper pipe 4.08 feet loss. In the vertical portion of the pipe a section of 2-inch long. The downtake pipe was of standard 2-inch galvanized Pyrex tube was inserted by means of stuffing boxes. Unions iron, into the vertical section of which was inserted a meter were placed in the line on either side of the glass tube to facilifor measuring the velocity of flow of liquid. I n the steam tate removal of the flowmeter. chest the steam inlet mas a t the top, the condensate outlet The choice of the device for indicating the rate of flow of a t the bottom on the under side, and t'he non-condensable liquid in the pipe presented several difficulties. Such a gas outlet' at the bot,tom on the upper side. The connections device should possess the following characteristics: (1) to the steam chest and vapor space which could not be flanged cause a minimum resistance to flow of liquid, (2) be simple in were all welded. By having the steam inlet at the top of the construction and easily read, (3) measure the flow of hot steam chest the condensate tends to be swept along in the water over a range of velocities, and (4) be compact so as to same direction as that of the steam and countercurrent to be easily placed inside the small space available. a f t e r that of the liquid being evaporated. The copper pipe con- trial it was found that a copper screen bobbin attached to a coil spring gave deflections which were proportional to the 1 Received M a y 2, 1930. Presented a t t h e meeting of the American flow of water in pounds per minute. The spring used for the Institute of Chemical Engineers, Detroit, Mich., June 4 t o 6, 1930. 2 Submitted in partial fulfilment of t h e requirements for t h e degree heat-transfer measurements was made of S o . 22 phosphorof master of science in chemical engineering a t t h e University of Minnesota. bronze spring wire with a coil diameter of about 0.5 inch. 3 Graduate student in chemical engineering, University of hlinnesota. The bobbin was prepared by shaping four thicknesses of 4 Associate professor of chemical engineering, University of hlinnesota.
I X D C S T R I A L A S D ENGINEERING CHEMISTRY
July, 1930
30-mesh copper screen into a section resembling a third of a sphere, lvith a solid piece of lead foil 1 inch in diameter a t the bottom. This was suspended from the spring with the contal-e surface up. A preliminary calibration with a weaker spring showed that if the results were plotted as inches elongation of the spring versus pounds of water flowing per minute the only effect of increased temperature was to change the zero reading of the spring. The results obtained a t 25', 50', and 74" C. are shown in Figure 2. The capacities needed, however, were found by trial to be greater than a t first estimated, so the S o . 22 spring was used giving the results in Figure 3. The temperatures of the outer surface of the copper pipe were obtained by means of copper-constantan thermocouples. The wires were attached to the pipe by cutting a small slot in it with a fine hack saw, inserting the wires, and closing the slot with a ball-peen hammer. The slots were then soldered over and the excess solder filed off smoothly and flush with the pipe surface. Other couples were placed in the vapor space to measure the steam temperature. Small thermocouple outlets were used to bring the couples through the pipe forming the steam chest. A Queen-Gr:ty potentiometer, type 3044 C, and a Leeds and Northrup galvanometer, type R, mere used to measure the e. m. f. of the thermocouples. The dial on this instrument reads directly to 5 microvolts, and can be estimated to * 1 microvolt, so that the measuring device was capable of an accuracy of about 0.1' F.
time for the system to come to equilibrium at this point because any changes in steam pressure or slight changes in vacuum may be followed with about a second lag with the thermocouples. During this last interval the cold-junction container was filled n-ith ice and the potentiometer balanced against a standard cadmium cell which was checked with a U. s. Bureau of Standards cell.
0
0
Method of Operation
"%
Condenser
En t r a m m e d Seporafor
Steam /n/ef
0.2
0.3
0.4
0.5
06
07
Figure 2
At the start of a run the level of the condensate was recorded with the time and after a half-hour was again read. The thermocouples were read several times during the run, but showed little \-ariation because the steam and vacuum were adjusted to keep the readings on the corresponding mercury manometers constant to within 0.1 inch. The water level was kept constant, but no readings were taken just after feed water was added. I t had been found that in heating up this feed water the velocity of circulation dropped to almost zero and the steam consumption dropped as evidenced by a rise in steam pressure. 911 runs made were for a period of 30 minutes, at the end of which time the condensed vapor was weighed to the nearest 0.01 pound. To obtain the velocity measurements desired in Series B the bobbin had to be read. This was done with an arrangement to avoid parallax and could be read to +0.01 inch except when the liquid surged. Then the readings were more approximate, but usually accurate to less than *0.03 inch in the most extreme cases.
Thermo coup/e ouf/efs
Nomenclature
Q = B. t. u. transmitted 0 = time in hours
Nefer
L = latent heat of steam in B. t. u. per pound Condemak Ouflef
feed
h/ef Figure 1-Diagram
0.1
5prin9 E/onpaf/on in Znrhes
The steam line \vas cleared of condensate by blowing steam through a condensate trap near the inlet to the apparatus. The trap was then shut off and the valve opened to the evaporator steam chest. d t the same time the valve a t the bottom of the condensed steam receiver was opened so that the steam could sweep the air from the system. This sweeping action continues during the entire heating period and also during the run, although to not quite such a large extent as the condensate valve is throttled donm. S o attempt nas made to study the effect of noncondensable gases on the steam film coefficient, hut precautions taken tend to minimize the effect.
F/ON
709
of Inclined-Tube Evaporator
The level of the liquid in the evaporator !vas maintained to + 2 inches at the top of the tube by adding water by gravity f l o from ~ an elevated container. If a run was to be made at a reduced pressure, the vacuum was adjusted roughly a t this time to obtain the desired temperature and the apparatus was allowed to run until thoroughly heated, usually when 10 to 20 pounds of vapor had come through the condensers. The steam and vacuum were then adjusted accurately and run for about 10 minutes longer. Ten minutes was ample
h = heat of liquid = (temperature-of boiling - temperature of inlet water) x 1 X pounds water evaporated per hour L1 = L x pounds water evaporated per hour
Q = total heat transmitted per hour
c)
=
h
A T u = over-all temperature drop ATh = steam-film temperature drop A T L = liquid-film temperature drop AT, = temperature drop through tube Tube dimensions : Inside diameter = 1.062 inches Outside diameter = 1.315 inches Length = 4.08 feet A I = inside area of tube 1.062~ 1 2 X 4.08 = 1.135 square feet A2
=
outside area of tube
+ L1
Ih'D CSTRIAL A N D ENGINEERING CHEMISTRY
710 1,3157 12 As = log mean average area
___ X 4.08 = 1.404 square feet
A4
=
- 1'135 = 1.269 square feet 1.404 2.3 log 1.135 cross-sectional area of tube
(1'062)2n = 0.00617 square feet 144 X 4 U = Over-all coefficient of heat transfer in B.t . u. per degree Fahrenheit per square foot of heating surface per hour Q 8 c= AT%X A i h, = steam-film coefficient in B. t. u. per degree Fahrenheit per square foot per hour 12, =
h~
k121Q
=
0 H A T t X Ai liquid-film coefficient in B. t. u, per degree Fahrenheit per square foot per hour
hL = -:AT, X AI AT, is obtained from equation: AT, X k X A3 Q= thickness of tube iri feet 8 k = thermal conductivity of copper = 220 Thickness of tube = 0.01064 foot A T p = 0.0000378
Q
Vol. 22, Yo. 7 i
0.0452
=
0.9592 X 62.4 X 60 X 0.00617
0.0448
=
0.96497 X 62.4 X 60 X 0.00617 1 0.9704 X 62.4 X 60 X 0.0061i
1
k2lg6
=
k21*Q
= 0.0445 =
The weight of circulating water per minute is obtained from Figure 3. Steam yelocity is in feet per second. This yelocity is due to the steam a t t h e top of the tube. Hovever, at the top of the tube the total velocity is the steam velocity plus the liquid velocity. The steam velocity may be calculated as ki X pounds of steam generated per hour specific volume of steam 3600 X A , k12'Q = 1251 k1193 = 167 k1'30 = 2 26 V, = log mean average velocity = feet per second steam velocity vm = liquid velocity steam velocity log liquid velocity
where kl
=
+
(
The experimental data are given in Tables I and 11. Table I-Experimental RUN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
STEAM TEMP. F. ~. 226,7 221.7 224.1 229.5 225.8 223.5 219.2 230.2 229.5 220.8 219.6 217.5 220.2 215.0 218.0 215.7 219.0 212.5 214.0 217.2 220.1
TUBE TEMP. F.
Data.
Series A
BOILIXG TEMP. 'F.
INLET WATER WATER EVAPORATED TEMP. PER HOUR F. Pounds
Data. Series B IKLET WATER SPRING TUBE WATEREVAPORATED ELONGATEMP. TEMP. PER HOUR TION F. F. Pounds Inch 0.26 86 0
Table 11-Experimental RUK
BOILIKG TEMP. F.
STEAM TEMP. O F.
86
a5 a4 85 84 84 a4 90
90 85 a5 88 88 91 91 91 86 86
s,r'n9 No 22 ~/on9af/bn/n fnches Figure 3
Calculation of T e m p e r a t u r e Drop t h r o u g h T u b e
Inlet liquid velocity is in feet per second. It is the velocity which exists at the inlet of the tube where there is no steam being generated. Liquid velocity may be calculated as ICz x pounds of circulating water per minute where
k2
=
relative volume of water a t boiling temperature 62.4 X 60 X Aa
86 86 85 82.5
S a m p l e Calculation
Observed Data (No. B-6): Steam temperature = 219.8' F. Tube temperature = 216.8' F. Vapor temperature = 195.1' F. Inlet water temperature = 84.0' F. Spring elongation = 0.56 inch Water evaporated per hour = 24.84 pounds
0.36 0.35 0.56 0.33 0.56
0.16 0.12 0.20 0.10 0.07 . 0.07 0.40 0.44 0.27 0.22 0.18 0.20 0.27 0.33 0.46 0.36 0.89
I N D U S T R I A L AND ESGIAYEERISG CHE.TIIXTRY
July, 1930
'ill
Calculations: L = 980.4 h = (195.1 - 84.0) X 1 X 24.84 2768 L 1 = 980.4 X 24.84 = 24380 Q/@
=
27148B. t. 11.
AT?' = (219.8" - 195.1') = 24.7" F.
AT, = (219.8" - 216.8") = 3.0" F. 27148 OI8 1- = ATtt X AS 1.269 X 24.7
11,
=
Q
(3
~
A T X A?
27148 1404 X 3 0
=
= 0.0000378 X 27148 = 1.03' F. A T L = (216 8 - 195 1) - 1.03 = 20.67" 27148 ''' = -~ = hL =
ATp
AT1 X
Ai
877 B. t . u. per degree Fahrenheit per square foot per hour
=
6440 B. t u. per degree Fahrenheit per square foot per hour
F 1158 13. t. u. per square foot per hour per degree Fahrenheit
1135 X 2067
L'elocity Measurement: Spring elongation = 0.56 inch = 52.5 pounds per minute (Figure 3 ) Steam velocity = k l X pounds water evaporated per hour 1.67 X 24.8 = 41.4 feet per second Liquid velocity = kz X pounds per minute 0.0448 >: 52.5 = 2.35 feet per second 41'4 = 14.15 feet per second Log mean velocity = 43.75 2.3 log 7 2.35
I n a similar way all the experiinental data were calculated and arranged in Tables I11 and IT'.
R1.s
10 11 12 13 14 15 16 17 18 19 20 21
14302 2690 8476 19922 11659 7930 1326 19480 19201 5035 36835 23000 29340 21340 25860 22337 27020 16252 30951 32670 38310
Table 111-Calculated Values. ATL ATp AT% ATI 15.7 3.0 12.16 0.54 10.4 0.4 9.90 0.102 0.32 12.8 1.1 11.38 18.1 3 . 4 13.945 0.755 15.4 2.3 12,66 0.44 13.1 1 . 4 1'. 40 0.30 8.3 0 . 3 I .95 0.05 18.9 4 . 4 1 3 , 7 6 5 0.735 18.7 3 9 14.08 0.725 10.1 0 8 9.11 0.19 24.4 6 0 17.01 1.39 23.5 4 7 17.93 0.87 25.5 6 1 19.29 1.11 20.1 3 7 15.595 0 . so5 23.2 1 7 , 7 2 5 0.975 4 5 20.7 3 4 16.455 0.845 23.7 4 9 1.02 17.78 17.6 2 5 14.485 0.615 5 4 17.43 24.0 1.17 27.3 6 6 19.465 1.235 30.1 7 6 21.05 1.45
Series A
U 719 204 523 868 596 477.5 126 812 810 393 1190 772 909 837 880 851 900 729 1015 947 1005
hv 3395 4780 5490 4170 3610 4030 3140 3140 3505 4480
4370
3480 4090 4100 4080 4670 3927 4620 4070 3520 3582
hL 1039 239 657
1260 812 612 146.8 1247 1202 487 1904 1130 1340 1204 1288 1195 1336
990 1560 1480 1606
Discussion of Results
The over-all coefficients for each temperature of evaporatiori are plotted against the over-all temperature drop in Figure 4. These curves are similar to those obtained for the vertical evaporator by Badger ( 6 ) , but in general the coefficieiits are higher. This is probably due to the fact that the surface of this one tube was kept as clean as possible and that only distilled water was used in the apparatus. Heat-transfer rates under plant conditions mould probably not reach these values. I t is significant, however, that Badger's (6) coefficients with a horizontal evaporator exceeded these values when the tubes were newly cleaned. It may also be expected that an inclined evaporator with a given length of tube and a n ample downtake pipe could give somewhat higher values than a vertical because the head of liquid in the: tubes is less and the resistance to downward flow of liquid may . purpose117 . . be made smaller as in this case. I n Figure 5 the liquid-film coefficients are plotted against the temperature drop across the liquid film. I n general, the
coefficients increase with the teinperature of evaporation and with the temperature drop. There are deviations from the average curve through experiiiiental values. but they are of no greater magnitude, perhaps, than may be expected in evaporator work. The following approximate equations hold for these curves: At 180" F., hL = 0.632 4Tt2.' At 195" F., hr, = 1.010 LIT^,^.^ At 210" F., hr, = 1.564 A T L ~ . ~
I n Figure 6 the liquid-film coefficients are plotted against the log mean velocity of the steam plus water flowing up the heating tube. S o theoretical significance is claimed for employing the log mean velocity here, as it is entirely empirical. Qualitatively, it is seen that the velocity a t the bottom of the tube mill be due to that of the liquid alone, as measured by the flownieter. Along the tube, as the liquid flows upmard and absorbs heat, steam will be formed which, working like a vapor lift, will cause a still greater velocity of flo~vy This increased velocity will cause a greater rate of heat transfer, forming still more steam. At the top of the tube the velocity will be quite high owing to this cumulative effect, certainly much higher than that due to the liquid alone. The Curves in Figure show that the values of hr, increase with increasing values of the log mean velocity but decrease for a given log mean velocity as the temperature of evaporation is decreased. For these curves it is found that, At 180" F., hr, = 97 Vmo.89 At 195" F., hr, = 120 Vmo.BB At 210" F., hL = 150 Vmo.*P
Elimination Of h~ from the two Sets fo110J%2TTaluesof ATL:
Of
equations
At 180" F., ATL = 7.49 V,0.356 At 195' F., ATL = 6.76 V7no.356 At 210" F., A T L = 6.20 Vmo.356
gives
the
INDUSTRIAL A N D ENGINEERING CHEMISTRY
712
Table IV-Calculated
RUN
Q/e
ATV
A Tu
ATp
U
ATL
Values. hv
Series B H i 0 PER hL MIN.
Lbs. 1 2 3 4
7333 12521 14452 21485 17376 27148 9592 5420 13096 11485 4943 16278 17031 21416 13851 10804 6873 8395 11535 10780 16100 18181 11221
5
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
12.8 15.5 18.9 21.4 20.2 24.7 15.6 12.2 17.5 15.4 12.5 18.8 22.3 23.6 19.4 17.8 15.4 14.8 17.3 17.1 20.5 19.4 13.0
452 637 603 792 678 866 484 351 590 587 311.5 682 603 717 563 479 355 447 526 496 620 739 680
1.0 1.9 1.9 3.1 2.2 3.0 0.85 1.0 2.3 1.3 0.9 2.3 4.0 3.6 2.3 2.0 1.2 1.3 2.2 1.6 3.1 3.0 2.0
These equations are indicated only as empirical equations which correlate the data given over the range of temperatures used. f600
f400
I
I
I
I
I
I
I
Vol. 22, s o . 7
STEAM PER LIQUID STEAM Loo MEAN HOUR VELOCITY VELOCITY VELOCITY Lbs.
560 831 779 1083 882 1158 589 435 783 740 381 902 851 986 738 620 434 561 694 629 846 1018 935
1.56 1.86 1.83 2.33 1.76 2.35 1.19 0.986 1.35 0.875 0.644 0,650 1.945 2.055 1.57 1.40 1.27 1.35 1,59 1.76 2.13 1.865 3.03
8.39 14.30 22 15 32.90 26.65 41.4 14.75 8.29 20.15 17.61 7.56 24.6 35.6 44.8 29.05 22.5 14.4 9.60 13.20 16.57 24.6 20.75 12.8
4.53 6.62 8.62 12.12 9.53 14.15 5.70 3.70 7.27 5.80 2.97 6.80 12.05 14.36 9.79 7.93 5.73 4.59 5.93 7.08 9.73 8.33 7.63
agree as well as they do, and surely this agreement indicates the general trend of results to be expected. Further work is needed to establish such an equation definitely.
0
71
I/
Table V-Relation of Heat-Transfer Coefficients to Velocities of Circulation. Calculated Values. Series B TEMP. RVN EVAPORATION @ !k &d EXPT. hL CALCD. hL DEVIATION
(F)o,8
2
F.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
210.2 210.3 194.8 l95,Z 195.0 195.1 195.0 194.8 195.0 194.8 194.6 195.2 179.5 179.7 179.8 179.4 180.0 210.6 210.7 195.0 195.1 210.8 211.3
Per cent - 5.4 3.6 - 3.8 2.1 0.7 - 3.7 1.7 5.85 +10.9
1001 1463 1752 2460 1930 2870 1152 749 1475 1178 602
251.4 340.5 393.4 516.1 425.1 584 281.3 199.3 342.8 286.4 167.4
592 802 810 1061 876 1202 579 411 706 345
$1013
2234 2660 1810 1465 1060 1012 1312 1436 1971 1840 1688
478 549.4 403.8 341 263.1 253.6 312 335.5 432.3 409.2 399.8
Si6 984 723 610 471 596 735 690 890 964 941
++- 0.6 0.2 +- 2.10 1.6 7.9
+ ++ + +
..
- 5.9
-
5.6 8.8
+-- 4.9 5,6 0.6
Lqwd f / / m Tempemfure Drop A Figure 5
They do indicate, however, the possibility that an expression might be found defining h~ in terms of the dimensionless groups employed for heat-transfer coefficients in turbulent flow. I n this region according to Morris and Whitman (.5), hd
=h(;)fz
(%)
where c = specific heat z = viscosity in centipoises k = thermal conductivity d = inside diameter of pipe in inches u = velocity of liquid in feet per second p = density of liquid in pounds per cubic foot
Accordingly, values of hd/k and d V , p / z were calculated as shown in Table V. When these values are plotted on log-log paper, for the three temperatures, straight lines result, as shown in Figure 7. If now the group cz/k or its reciprocal, k / c z , is taken into consideration, it is found that the equation hd _ -- 4.15
k
(k)(y) dVmp
0.8
represents the conditions with an average accuracy of + 5 per cent, where k , c, z, and p are taken a t the temperature of evaporation. No claim is made that these data definitely establish this equation but it is significant that the results
Log
Mean Y e l o n f y - f e e f p e r ~ e c o n d Figure 6
I n Tables I11 and IV are given the calculated values for the steam-film coefficients, h,. In general, these vary considerably and are somewhat higher than data published on horizontal tubes (6, 7 ) . This may be due in part to the fact that many of the temperature drops through the steam film were low and therefore subject to greater relative error than those
INDUSTRIAL AND ENGINEERING CHEMISTRY
July, 1930
713
obtained a t greater values of ATt. This is inevitable, because a slight error in pipe-surface temperatures makes relatively large errors in the values of h,. I n this apparatus the flow of steam was in the same direction as the flow of condensate. This would aid in the removal of condensate from the pipe surface and result in an increased coefficient. Literature Cited (1) Badger, Trans. A m . Insl. Chem. Eng.,13 (II), 139 (1921). (2) Badger and Shepard, I b i d . , 13 ( I ) , 139 (1920). (3) Clement and Garland, University of Illinois Expt. Sta., Bull. 40 (1909). (4) Kerr, Louisiana Agr. Expt. Sta., Bull. 149, 27. ( 5 ) Morris and Whitman, IND. ENG.CHEM., 20, 234 (1928). (6) Pridgeon and Badger, I b i d . , 16, 474 (1924). (7) Van Marle, J. I. and E. C . , I b i d . , 16, 458 (1924).
dLmE Z
Figure 7
Industrial Public Relations from the Engineering Standpoint’ Leon V. Quigley BAKELITR CORPORATION, 247 PARKA v z . , A-RWYORK, N. Y.
M
’
ODERF industry, built fundamentally on research,
production, and sales, has nom developed an auxiliary department which coordinates with the first three in relating industry to its market or “field of force.” This organized effort-interpreting and relating industry to its clients and to the general public-is designated by the term “public relations.” The work embraces several distinct lines of activity, but always there are two principal standards which it is expected to meet. From the standpoint of science technical information must be unequivocally accurate; commercial effectiveness demands that it be interesting and keyed to the readers’ viewpoint. Granting this twofold standard, public relations work in the chemical industry can proceed most effectively when its purpose and methods are understood and constructively criticized by the chemist and engineer. no less than by industrialist and commercial executive. In citing the departments of research, production, and sales as fundamental in modern industry, we are, of course, additionally aware of the importance of finance and administration. We are assuming, however, that these factors underlie industry as a whole, and in the inter& of conciseness we shall not elaborate on their function. Likewise we are mindful of numerous other departments in industry, such as purchasing, advertising, engineering service.. The scope of the present paper will not permit a discussion of these several related departments. For the purpose of this rbsumb, they will be understood to be included under the three major divisions, research, production, and sales. So, too, public relations activity is related, particularly to sales. I n some measure it could be classed under each one of the three fields, but in view of the scope of duties it is probably best understood when separately considered. To a limited extent public relations work can be performed, and is performed, by workers in every department of industry. In organizations of considerable size, however, the field of the activity becomes 1 Received March 8, 1930. Presented before the Division of Industrial and Engineering Chemistry at the 79th Meeting of the American Chemical Society, Atlanta, Ga., April 7 to 11, 1930.
automatically so large that a separate departmental unit is assigned the task of its direction. The work of such a department may be defined as an organized and sustained liaison effort dedicated to the task of coordinating an organization with its market or field of senice. In this function it does not replace or duplicate the work of service engineering and sales, but serves rather as an auxiliary. An interesting fact is that public relations activity does not operate like sales promotion and advertising, within the scope of their correct definition. True, it is conducive to sales results, but its methods are those of mediation rather than promotion. I t studies and seeks to improve the relationship between industry and its market, but it differs from advertising in the content, method, and appeal of its work, and notably in the regulation of emphasis. The economic value of public relations work is found in the fact that it serves to relate industry to its market. Thus it participates in the development, direction, maintenance, or increase of commodity interchange. Commodity interchange is usually the raison d’etre of business, commerce, or industry. Origin of Public Relations Work
The origin of public relations work can be traced to the older profession of law. Analogies are found in the logic of its procedure, the advisory nature of its counsel, and in the reliance it places on expert testimony. I n industry the advisor in public relations is as yet less understood in his function than the corporation counsel in his legal function. This condition appears natural, however, when we realize the relative antiquity of the legal profession. Probably difficult to define was the profession of the first lawyer who stood forth t o interpret the position of a client. Organized legal counsel developed only after the premise was granted that there was both justification and value in having some particular consultant designated to study the procedure of the law and to specialize in presenting the other fellow’s case at court. Like the business of law, the work we are discussing is as old as human experience. The role of the ambassador is not
