680
I S D C S T R I A L A S D ESGIA1%ERISG CHEMISTRY
1-01. 19, KO. 6
of Sulfite L i q u o r i n Forced C i r c u l a t i o n Evaporator (Summary of D a t a ) FIRSTEFFECT SECOND EFFECT THIRDEFFECT Total time of operation up to end of first series 7 hours 10 min. 20 hours 00 min. 26 hours 55 min. Total time of operation up t o end of second series 73 hours 5 5 min. 87 hours 25 min. 100 hours 20 min. Number of test runs averaged 13 24 23 Average per cent total solids 9.8 14.7 21.4 Table I-Evaporation
Average steam temperature, F. Average vapor temperature, F. Average temperature drop, O F. Average velocity, feet per second Average pressure drop, feet Hz0 Average coefficient (B. t. u. per square foot per hour per a First series of runs, under fourth effect conditions. b Second series, finishing a t atmospheric pressure.
F.)
230.79 210.67 20.12 11.5 14.75 i34.5
sulfide, but the surface of the tubes was smooth and metallic to the touch and nothing that can by any stretch of the imagination be called scale was present. The principal result of these experiments may therefore be stated as follows: I n these tests, a t the end of approximately 150 hours of operation, no scale had been formed in this evaporator. Considering the performance of ordinary evaporators on this liquid, this result is so remarkable that it stands out as the principal feature of the test. The next most important item is obviously the very high value of the coefficients. The reason for the low values in the first effect cannot even be guessed. It could not have been due to scale formation by the raw liquor, because the second effect operation certainly would not have dissolved such scale and first effect operation the second time over
214 0.5 194.10 19.90 7.9 15.23
192.59
167,25 25.31 7.1 19.05 723
989
FOURTH EFFECT 63 hours 05 min. 148 hours 00 min. 60a 35b 39.9 50.3 175.17 246.76 130.94 210.92 44.53 35.84 9.4 7.6 22.64 24.00 346 337
checked these results. The results are more erratic in the first three effects than could be desired. This variation is undoubtedly due to irregularities in rate of feed and rate of drawing off thick liquor. The concentration in each run was based on a single determination of specific gravity and may not always have reflected the average density throughout the run. Even allowing for the wide fluctuations in the data, the curve still shows a coefficient several times as high as could be obtained in either a standard vertical or standard horizontal tube evaporator, even when clean. Acknowledgment
The writer wishes to acknowledge his indebtedness to the Swenson Evaporator Company, who made all the arrangements for the experimental work and financed it throughout.
An All-Glass Distilling Tube without Constriction’ By Howard J. Lucas CILIFORSIA ISSTITCTE O F TECHSOLOGY, PASADENA, CALIF.
T
HE usual distilling tube is constricted near the bottom a t the very place where maximum capacity is needed. Peters and Baker2 overcome this difficulty by putting a wire through two small holes in the wall near the bottom of the tube and placing upon this an openwork ball of wire t o act as support for the column of 5-mm. glass rings. The presence of copper is objectionable when acids or substances ha\ ing oxidizing properties such as nitrotoluene are being distilled. The accompanying diagram (Figure l , a) shows the construction of a tube composed entirely of glass and having a t the bottom a capacity only slightly less than the rest of the tube. Three or four indentations in the wall, all a t the same lerel as shown b in b, support a hollow-glass nipple, c. Enough holes a r e b l o w n in the upper half of the nipple to take care of decreased capacity resulting from the closing of openings by the glass rings above resting against them. It is evident that C the decrease in the capac1 Received
0
2
Figure 1
March 14,1927.
T H I SJ O U R N A L , 18, 69
(1926).
ity of the tube a t the level of the indentationcorresponds to the cross-sectional area of the
indentations and of the wall of the nipple. I t is probable that this decrease is not much greater than that resulting from the presence of the glass rings higher up. This type of tube is useful TT here liquids of high boiling point are being distilled and where the run-back is large. The distillation of rt mixture of nitrotoluenes through a column of glass rings 5 X 5 mm. can be accomplished without troublesome holdup in the column and with a fair separation of the ortho isomer in one distillation. A modified Pim’s chlorinating apparatus4 is shown in Figure 2. This has given satisfactory results in the chlorination of toluene to benzyl chloride when filled with a 20-cm. column of glass rings 5 X 5 mm.
G
‘J
7\
Y Figure 2
Martin, “Industrial and Manufacturing Chemistry,” Vol. I , p. 366b, Crosby Lockwood and Son, London, 1915.
Celanese Corporation Doubles Capacity of Maryland Plant -The Celanese Corporation of America, formerly the American Cellulose and Chemical Manufacturing Company, Ltd., which recently changed its name and increased its capital stock by $5,500,000, plans t o award contracts a t once for the erection of buildings t o house machinery which will double the capacity of the maximum output of the present plant a t Amcelle, Md., a suburb of Cumberland, Md., a t a cost of about 965,000,000. A contract has already been awarded to the Cumberland Contracting Company to build a new road to the main plant, 26 feet wide. A new brick office building will be erected and another artesian well is being drilled. It is understood that the Baltimore and Ohio Railroad will build a subway under its fill to connect two sides of the plant.
