MARCH, 1937
INDUSTRIAL AND ENGINEERING CHEMISTRY
MAX-24.9
8 c_
1 1.0
I
data with such success that considerable confidence is now attached to the use of these heat of cracking determinations in calculations of this character. It is hoped that others will find these results to be a worth-while addition to our knowledge of the art of cracking. The voluminous data on gas composition are not included for the sake of brevity.
-73
I
1.5
353
I
I
2 .o
I
I
2.5
I
I
3.0
I
Acknowledgment
MOLS PRODUCTS PER MOL CHARGE 3 I us. MOLES PRODUCED FOR EAST TEXASGASOIL FIGURE 8. HEATOF REACTION
(Numbers beside points &represaures in pounds/square inch
gage)
The data on Barbers Hill and recycle gas oils are primarily of interest in the confirmation they afford of the conclusions derived from the data on East Texas gas oil. I n Figure 8 for East Texas gas oil, the results indicate a relation which is independent of the pressure. I n this connection it should be mentioned that the energy which corresponds to the expansion of products against even the highest superimposed pressure is negligible in comparison to the relatively large heat quantities which appear on the charts. However, this workenergy correction is properly applied in the computation of the net heat of reaction values. I n conclusion, it should be reported that heat balances of operating plant cracking stills have been made using these
The authors wish to acknowledge with thanks the permission given by The Atlantic Refining Company to publish the work at this date. A s s i s t a n c e e i v e n bv Hugh W. Field in editing the paper is acknoGledged &th auppreciation. Finally, the authors are indebted to the many who assisted in the original experimental work, particularly C . A. Porter and F. I. L. Lawrence, whose constructive attention to important details of operation distinguished their efforts during the progress of the work.
Literature Cited (1) Egloff, G., and Levinson, B. L., J . Inst. Petroleum Tech., 20, 343-66 (1934). (2) Leslie, E. H., and Potthoff, E. H., IND.ENG.CHEM.,18, 776 (1926). REICFIIVBD August 29, 1936.
Hydrogenation Tests on
Canadian Coal T
HIS paper presents the results of hydrogenation tests on a typical bituminous coal from eastern Canada together with a description of the equipment and method developed a t the Fuel Research Laboratories of the Department of Mines for such tests. The throughput capacity of the equipment is one gallon of raw material per hour, and the method employed is based on continuous operation, which gives a better indication of the behavior of the coal in commercial equipment than does batch operation. Future work will include tests on several other Canadian coals varying in rank, and on bitumen from the bituminous sands of Alberta. The results of this work, which is now in progress, will be published periodically.
Equipment Equipment for the compression and storage of hydrogen is shown at the left of Figure 1. Hydrogen, purchased in shipping cylinders, is passed through a meter to a small gas holder, not shown in the drawing, and thence t o a three-stage com ressor. Here it is compressed as required by the experiment anfstored at high pressure in two cylinders. Whenever the compressor is in operation, the hydrogen is continuously sampled at the inlet to the second stage and analyzed by an automatic recorder. The recorder operates a bell when the purity of the hydrogen is lower than 95 per cent. This precaution is taken in order to prevent air or oxygen from being com ressed with the hydrogen. The compressor is driven by a variatle-speed gear, and its rate
T. E. WARREN AND R. E. GILMORE Department of Mines, Ottawa, Canada
can be adjusted so as to maintain a constant pressure in the system. The equipment for charging coal paste to the reaction chamber is shown in Figure 1, at the right of the high-pressure storage cylinders. The paste is mixed in a large container, not shown in the drawing, and transferred from it into the feed funnel from which it passes t o the feed pump. The pump has an adjustable stroke by which the rate of charging can be regulated. A Bourdon gage on the line to the reaction chamber is used to indicate the presence of any obstruction between the pump and the highpressure receiver. The reaction chamber is a tube 10 feet long, 4 inches in outside diameter, and 2.74 inches in inside diameter, made from 18-8 chrome-nickel steel with a carbon content less than 0.07 per cent. It is externally heated by two heaters situated on the upper and lower halves of the chamber. The heating elements are vertical loops of wire held in place by specially shaped bricks. The bricks, in which diatomaceous earth is incorporated in the cement, serve as heat insulation. The temperature of the wall of the reaction chamber is measured at ten points by iron-constantan thermocouples. Two of these are used to operate a two-point temperature controller which controls each heater independently. A drawing of the upper end of the reaction chamber is shown in Figure 2. The bottom of the chamber is closed in the same way. The closures are designed according to the unsupported area principle (1). The pressure acting outward on the entire cross-sectional area of the reaction chamber is su ported by a gasket of comparatively small area which is forces against the wall at a pressure greater than that in the chamber. The joint is therefore tightened by an increase of internal pressure. Inside the reaction chamber, at the bottom, two valves prevent the return of the contents into the hydrogen or liquid feed
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INDUSTRIAL AND ENGINEERING CHEMISTRY
lines. A third opening in the bottom closure is utilized to drain liquid from the chamber when necessary. The hydrogen, introduced at the center of the bottom closure, passes into a p i p e 1 inch in diameter and through it to the upper part of the chamber. The pipe stands on three short legs on the bottom closure, so that liquid is carried upwards inside it as in an air-lift pum By this means the in the reaction cham er is well agitated. The excess of hydrogen together with vapor and liquid products is withdrawn at a point 9 inches below the top of the reaction chamber, and p a s B e s into the cooler. A n o t h e r outlet in the upper closure is available for the release of gas ressure above the liquid {vel. The total volume of the reaction chamber is 690 cubic inches. Deducting the volume of the gas space at the top and that of the central pipe, the volume occupied by liquid is 590 cubic inches. A thermocouple e x t e n d s through the upper closure to a Doint inside the central pip; The cooler, t h r o u g h which the products from the reaction c h a m b e r pass, is a tube 7 feet in length, 0.54 inch in outside diameter, and 0.30 inch in inside diameter. It is s u r r o u n d e d b y a water jacket through which hot or cold water may be run. The high-pressure receiver, i n t o which the cooled products are discharged, is 5 feet long and is made from tubing of the same composition and diameter as the reaction chamber. The closures are also of the same type as those of the reaction chamber. The part of the product which is liquid at the reaction pressure and ordinary temperature, including dissolved hydrocarbons of low molecular weight, separates from the gas in this receiver. The li uid product is discharge3 from the highpressure receiver through a coil of tubing 20 feet in length and 0.0625 inch in inside d i a m e t e r . The purpose of this coil is to reduce the velocity of flow through the d i s c h a r g e valves. When it is not used, the valve controlling the rate of discharge is eroded so deeply during only a few minutes of use, that it cannot be fully closed. The d i s c h a r g e
$9
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MARCH, 1937
INDUSTRIAL AND ENGINEERING CHEMISTRY
valves have replaceable stems and seats, and two are used in series so trhat repairs can be made while a run is in progress. An outlet at the bottom of the receiver is used when the liquid is to be completely removed. The gas from the top of the receiver is largely hydrogen and is delivered back to the bottom of the reaction chamber by means of the high-pressure recirculating pump. This pump is a onestage booster compressor. It is run at constant speed, the rate of recirculation of gas through the reaction chamber being regulated with a by-pass valve and measured by a high-pressure flowmeter. A low-pressure manifold is connected to the gas line from the top of the receiver. It is used to discard a measured quantity of gas, or to return it to the gas holder. The pressure indicated by the gage at the top of the receiver is recorded as the pressure of the reacting materials, the drop in pressure through the cooler being negligible. For purposes of operation, the pressure is measured at other points as indicated in Figure 1. All the Bourdon gages are calibrated against a piston gage. Sections of the apparatus which come into contact with the reaction products are for the most part made of 18-8 chromenickel steel in order to resist corrosion. The head of the booster compressor, including valves and springs, and also many of the pipes and fittings are made of this alloy. Almost all of the tubing used is 0.25-inch pipe size of "extra strong" weight, having an external diameter of 0.54 inch and an internal diameter of 0.30 inch. Most of the pipe connections are made with ordinary tapered threads, but those which are subjected to heat are made as shown in Figure 2.
A more detailed description of some of the auxiliary equipment is t o be found in a previous publication (5).
Method of Operation The coal to be hydrogenated is powdered in a paddle-type pulverizer, after which practically all of it is capable of passing a 30-mesh screen and most of it is much finer. It is then mixed with an equal weight of oil which is usually a fraction of the product from a previous run. The catalyst is added to the mixture in the form of a powder. The solids settle out of the paste to some extent, so that the mixture must be stirred while it is being charged. The pitch, which was removed from the reaction chamber
l
0
FIGURE
Scala of inchea ,
P
q
l
2. CLOSURE OF REACTION CHAMBER
355
a t the end of the previous run, is weighed and again introduced into the reaction chamber. Hydrogen is compressed into the system until the operating pressure is attained; this is usually 3000 pounds per square inch. The heaters are then switched on, and the reaction chamber is heated as rapidly as possible to 662" F. (350" C.). At this temperature, hydrogen recirculation is begun. Heating is continued until the operating temperature is reached. About 3.5 hours are required to reach this temperature, which is usually 842" F. (450" C.) as measured by the controlling thermocouples (Figure 1, C). During the run the pressure is kept constant by adjusting the speed of the compressor. The temperature of the wall of the reaction chamber a t the location of the controlling thermocouples is kept constant by the temperature controller. The temperatures measured by the other thermocouples vary slightly and are recorded every hour. The rate of charging is usually about 9 pounds of paste per hour. The liquid in the high-pressure receiver is discharged a t intervals of about 20 minutes. The rate of gas recirculation is maintained a t about 5 cubic feet per hour, reckoned a t the temperature and pressure of the reaction. When all the paste has been charged, the heat is turned off and the reaction chamber is allowed to cool to 572" F. (300 C.), at which temperature hydrogen recirculation is stopped. The gas pressure is released from the chamber a t a temperature between 392" and 572" F. (200" and 300" C.) to avoid frothing of the pitch which would occur if the pressure were released a t room temperature. Samples of the recirculating gas are taken when the temperature in thereaction chamber has risen to 662"F. (350' C.), when reaction temperature is reached, after 3 hours of charging, a t the end of the charging period, and during the cooling period when the temperature has fallen to 662 " F. Readings of the inlet meter, the volume of the gas holder, the pressure on the high-pressure system, and the temperature of the reaction chamber are recorded a t the time each sample is taken. The consumption of hydrogen during the period between any two samples can be calculated from these data. It is assumed that the amount of hydrogen absorbed a t temperatures lower than 662" F. (350" C.) is negligible, and the consumption during the whole run is considered to be that during the period between the first and last gas samples. After the run, when the reaction chamber has cooled, the closures are removed and the pitch is melted and run out. The amount recovered is weighed in order to complete the weight balance. Samples of the pitch are extracted in a Soxhlet apparatus with carbon tetrachloride, the insoluble residue is then ignited, and the amount of ash determined. The difference in weight between insoluble residue and ash, the "combustible solid residue," together with the similar residue from the liquid product, is taken as a measure of the coal not converted to liquid or gas. The liquid product removed during the run from the receiver is similarly sampled and extracted. A sample of the liquid product is also distilled in a Hempel apparatus. Separate fractions are collected and weighed a t boiling points of 338" F. (170" C.), 446' F. (230" C.), and 572" F. (300' C.). A weight balance of materials introduced and recovered is made. The hydrogen consumed is included with the materials charged. The difference between the material introduced and the products recovered is reported as "gas plus loss," but may safely be assumed to be almost entirely hydrocarbon gases produced in the reaction. A separate estimation of "adherent coke" is made. This coke forms on surfaces submerged in the liquid in the reaction chamber and resembles in appearance a crystalline lacquer. The amount formed is insignificant in so far as the weight balance is concerned, but it might be important if it
INDUSTRIAL AND ENGINEERING CHEMISTRY
356
continued to accumulate. The amount is determined by removing the "hydrogen lift" pipe from the chamber and weighing it before and after removal of the coke. The yields as reported are based on the charge of ash- and moisture-free coal. They are corrected for changes in the amount and composition of the pitch. The fractions of high molecular weight, which are recovered from the products by extraction with carbon tetrachloride, are included in the total oil. A weight equal to that of the vehicle is deducted from the total oil to give the net yield of oil from coal. The yield of gas includes the distillation loss. Thus the net yields reported are the weights of the various products which would be obtained per hundred parts of ash- and moisture-free coal in continued operation.
Experimental Results The operating details and results of the most recent series of runs are reported below. I n this series, nine runs were made on one coal in order to determine the effect of changes in the operating variables, pressure, rate of charging, and temperature. The durations, exclusive of heating and cooling periods, were 6 to 8 hours. However, although operation was so often interrupted, the series was continuous in materials. The pitch in the reaction chamber was removed only for weighing and analysis, and then was replaced. The vehicle in each run, except the first, was a high-boiling fraction from the previous run. The coal used throughout the series was washed slack originating in the Harbour seam of the Sydney area in Nova Scotia. This coal is classified as "high volatile bituminous," and has the analysis and characteristics shown in Table I. OF COALUSEDIN RUNS TABLEI. CHARACTERISTICS
Proximate Analysis
Ultimate Analysis
% Moisture Ash Volatile matter Fixed carbon
2.1 3.0 37.3 57.6
% Carbon Hydrogen Ash
79.9 5.7 3.0 1.1 1.7 8.6 14,370 Good
Sulfur
Nitrogen Oxygen
Calorific value, B. t . u. per lb., gross Coking properties, by coke-button grading Ash Analvsis
%
Total
2.29 25.76 17.72 6.65 0.94 35.44 0.86 4.09 0.49 0.20 0.44 4.77 99.65
-
The coal was pulverized in two batches. The first of these, containing 2.1 per cent of moisture and 3.0 per cent of ash, was used up to, and including, the fourth run. The second, containing 2.4 per cent of moisture and 3.3 per cent of ash, was used in the subsequent ruris. The screen analysis (U. S. Standard Screen Series) of the first batch is as follows: % Through 16-mesh on 30-mesh Through 30-mesh on 50-mesh Through 50-mesh on 100-mesh Through 100-mesh on 200-mesh Through 200-mesh
0.5 3.2 16.7 25.4 54.2
The vehicle used in the first run was a fraction of hightemperature tar boiling above 446' F. (230' C.). It was
VOL. 29, NO. 3
found in previous experiments that low-temperature tar is also a suitable vehicle but that lubricating oil is not. I n each of the subsequent runs, the vehicle was produced from the liquid product of the previous run. The vehicles for runs 3,5, 6,8, and 9 were produced by distilling off the fractions up to 446' F. (230' C.) without rectification, and recovering as much as possible of the higher boiling oil by steam-distillation to coke. The vehicles for runs 2 and 4 were produced by distillation to coke without steam, discarding the fractions u p to 446" F. That for run 7 was produced by filtering the product of the previous run and removing the low-boiling fractions as before. The loss as coke in the distillation was about 12 per cent of the oil charged to the still. Because of this loss and also because additional quantities were required for other purposes, oil of comparatively low-boiling range was included in the vehicles so that they were more volatile and more fluid than those which would be used in commercial practice. The vehicle used in run 6 had a specific gravity a t 60" F. of 0.998, and distilled in Hempel apparatus a t atmospheric pressure as follows :
' F. Up to 446 446 t o 518 518 t o 572 Above 572
Fraction e
a.
Up to 230 230 to 270 270 t o 300 Above 300
Per Cent b y Weight 19.3 20.6 16.1 44.1
The vehicle contained a considerable quantity of oil boiling below 446' F. in the Hempel apparatus, although the fraction boiling below this temperature in the larger still had been removed. The catalyst used in all the runs was stannous oxide which was added to the paste in powder form before charging. The amount used was 5 per cent of the coal. I n the present series, the first and second runs were made for the purpose of establishing steady conditions and the eighth was interrupted. The results of these three runs are, therefore, not comparable to the others. The conditions and results of the other runs are summarized in Table 11. The temperature item of Table I1 is the mean of measurements by the two thermocouples opposite the control points taken a t 1-hour intervals during the run, exclusive of heating and cooling periods. This method of recording was adopted because the temperature indicated by the thermocouple extending through the upper closure is ordinarily about 27" F. (15' C.) lower than the temperature of the control points. It is also lower than the average temperature of the charge, because the paste is introduced a t room temperature a t the bottom of the chamber and immediately carried up the central pipe past this thermocouple. The ((rate of discharge" of gas is the rate a t which the gas was passed out of the system through the wet meter shown a t the right of Figure 1. I n the earlier runs of the series this was done for the purpose of removing accumulations of methane and other undesirable gases from the recirculating system. I n later runs it was found unnecessary to purify the hydrogen in this way and no gas was discharged in runs 7 and 9. Another operating variable, the rate of recirculation of hydrogen through the reaction chamber, was not purposely changed in any of the runs and for this reason is not recorded in Table 11. The rate changed to some extent during each run because of variation in the density of the gas. At the finish of the runs, when the density was highest, the rate was 4 to 6 cubic feet per hour a t the temperature and pressure of the reaction. The highest rate, a t the beginning of run 9, was 9 cubic feet per hour. The sum of the yields of the products of each run, as shown in Table 11,is not exactly equal to 100 plus the hydrogen con-
INDUSTRIAL AND ENGINEERING CHEMISTHY
MARCH, 1937
357
TABLE 11. OPERATING CONDITIONS AND YIELDS Run
Operating Conditions Temperature, ' F. Temperature a C. Pressure, podnds per square inch Rate of charging, pounds of paste per hour Rate of discharge of gas, CU. ft. per hour at room temperature and pressure Liquid Product Solids insoluble in CClr, per cent Ash in insoluble solids, per cent Distillation of Liquid Product WaLar
O i i i k t i o n to 338' F. (170° C.) Oil fraction 338' to 446" F. (170' to 230' C.) Oil fraction: 446' to 572O F. (230' to 300' C.) Residue,above 572" F. (300' C.) Distillation loss Pitch from Reaction Chamber Solids insoluble in CCIr, per cent Ash in insoluble solids, per cent Recirculatine - Gas Hr after heating to 662O F. (350' C.), per cent Ht at start of charging, per cent Hr after 3 hours of charging, per cent Hn at end of charging per cent Hn after cooling to 66b F. (350' C J , per cent Yields, Per Cent of A. M . F. Coal Hydrogen consumption Net oil from coal Gas Ius loss Comgustible solid residue Water Adherent Coke Coke, pounds per sq. ft. per hour (I
4
5
6
7
9
829 443 2940 8.83
833 445 2430 9.01
833 446 2940 9
831 444 2940 6 04
832 444 2940 8.92
857 458 2940 8 70
34.0
38.5
18.8
16.3
0
0
6.36 57.9
5.76 56.6
.. ..
3,90 46.5
13.6 49.6
3 56 41 9
4.85 4.29 17.0 36.4 37.0 0.47
4.98 5.88 15.8 29,s 42.6 0.89
5.67 7.26 15.8 26.9 43.3 1.03
4.80 4 36 11.9 29.6 48.4 0.92
5 6 13 27 45 0
32.6 52.0
30.8 56.4
50.9 40.8
33.1 45.8
53 6 36 3
95.3 93.4 86.8 84.5 84.1
97.3
96 0 94.9 80.9a 82.8 83.5
97.4 96.2 85.4 78.7 82.1
92 4 92 1 80 4 68 2 65 4
8.0 77.6 15.7 6.3 7.7
7.1 72.5 23.2 4.4 7.4
.. .. .. ..
10 53 7 32 17.6 8.5
6.1 73.0 22.2 3.5 7.3
8 54 31 16 8
...
0.0022
..
0.0025
0.0032
3
... ... ... 85.1
.. .. ..
.. .. .. 35.3 49.1
9a:3 80 .'7
..
..
55 92 6 9 5 50
3 9 0 6 0
0 0025
Sample taken after 4.25 hours of charging.
sumption. This is because there is a small difference between the weight of the ash plus the catalyst charged and the weight of the ash in the products. A sample of the liquid product of run 3 was sent to the U. S. Bureau of Mines Experiment Station a t Pittsburgh, where it was analyzed (analyzed by C. H. Fisher, and results reported by H. H. Storch, supervising chemist, Physical Chemistry Section). A summary of the results of the analysis reported is as follows: The liquid product was a brown, fairly mobile oil having a stron odor of ammonia and phenols. The filtered oil had a specifc gravity of 1.014, which is an indication that the material is largely aromatic and phenolic. An acetone solution was highly fluorescent, which is usually interpreted to mean that polynuclear aromatic hydrocarbons of high molecular weight are present. The products of distillation, es ecially the higher boiling fractions, darkened on standing. &e last fraction that could be distilled solidified on cooling to room temperature. No solid was obtained from the other fractions, in which respect the oil is different from coal tars roduced by carbonization. As much of the product could be $stilled at atmospheric pressure as at a ressure of 2 inches of mercury, or lower, the distillate in each case geing 88 to 89 per cent by volume of the charge. A distillation by the two-stage analytical method of the U. S. Bureauof Mines as used for coal tar ( 4 ) gave the following yields from the second distillation: Boiling Range of Fraction
F.
c.
Per Cent by Volume of Crude Oil
Analyses (made a t the Fuel Research Laboratories, Ottawa) of the gas samples taken from the recirculating system during run 9 are given in Table IV. TABLE 111.
CHAR.4CTERISTICS OF
Boiling Range F. O c. T o 302 T o 150 302 to 347 150 to 175 347 to 392 175 to 200 392 to 437 200 to 225 437 to 482 225 to 250 482 to527 250to275
Volume
cc .
O
TABLE Iv.
DISTILLATION FRACTIONS A. P: I. Gravity
. .. .
9.5 6.5 25.5 35.5 35.0 32.0
SAMPLES OF
Phenols
.... .... 3.75
... ... 33.5
6.25 6.0 4.50
25.75 14.0 8.5
iA:i
14.4 14.0 11.6
GASFROM RECIRCULATING
Heating Period Start at 662' F. of (350' C.) Run Carbon dioxide Unsaturates Oxygen Hydrogen Carbon monoxide Methane Ethane Nitrogen
Amines % ..
3 Hours after Start
End of Run
~i
16.5.
In another distillation from the Hempel flask, fractions collected at intervals of 45" F. (25" C.) were examined. The results are given in Table 111.
Cooling Period at 662O F.
%
%
%
%
%
0.2 0.0 0.3 92.4
0.2
0.1
0.0
0.0
0.1 0.3 0.3 68.2 1.8 18.7 7.9 2.7
0.1 0.2 0.3 65.4 2.2 21.2 7.6 3.1
0.6
3.4 0.9 2.2
0.3 92.1 0.8 4.9 0.5 1.2
0.3 80.4 1.1 11.3 4.3 2.5
%
A
SYSTEM
A sample of the hydrogen introduced in the same experiment had the following analysis: Carbon dioxide Oxygen Hydrogen
The distillate up to 572" F. 300' C.) was analyzed for tar bases and acids by the U. 8. ureau of Mines method (a); amines and phenols were resent to the extent of 4.9 and 16.2 per cent, respectively. e neutral oil was analyzed for olefins, aromatics, and paraffins (3); the yields as per cent by volume of the neutral oil were olefins 9.9, aromatics 73.6, and para5ns
V."
0.3 0.5 96.3
% Carbon monoxide Methane Nitrogen
0.7 0.4 1.8
Of the runs shown in Table 11, 3, 5, and 7 were made under the same operating conditions. The principal purpose of this repetition was to produce uniform pitch and vehicle for runs 4, 6 , and 9, in which the conditions were varied. Run 2, not shown in Table 11, was also made under standard conditions, so that with the exception of details of minor importance runs 4,6, and 9 each differ from run 3 only by the alteration of one condition of operation.
358
INDUSTRIAL AND ENGINEERING CHEMISTRX
Some minor changes in the method, having an insignificant effect on the quality of the pitch, were also made in runs 5 and 7. Of these changes, the most important was the discontinuance of discharging gas from the recirculating system. It was a t first thought that this was necessary in order to maintain a sufficiently high concentration of hydrogen. However, a comparison of the purity of the hydrogen at the ends of runs 3, 5, and 7 shows that reduction of the rate of discharge makes only a small difference. The impurities in the hydrogen are removed largely by solution in the liquid product, so that discharging a part of the gas is practically ineffectual as a means of purification. For this reason it was discontinued in subsequent runs. Comparing the data of runs 4 and 3 in Table 11, it can be seen that a reduction of 510 pounds per square inch from the standard operating pressure causes only a small change in the quality and yields of the products. Comparing runs 6 and 3, a reduction of about one-third in the rate of charging resulted in a larger consumption of hydrogen, a smaller yield of oil, and a larger yield of gas and of solid residue. I n run
VOL. 29, NO. 3
9, an increase in temperature of 28’ F. (15.5’ C.) produced results similar to those caused by the slow charging of run 6. The original conditions of run 3 gave better results than any others which were tried.
Literature Cited (1) Bridgman, P . W . , “The Physics of High Pressure,” p. 35, London, G. Bell and Sons, L t d . , 1931. (2) Fieldner, A. C.,and Davis, J. D . , U. S. Bur. Mines, Monograph 5, 145 (1934). (3) Ibid., p. 146. (4) Kester, E. B., Pohle, W. D . , and Rookenbaoh, L. P., U. 8. Bur. Mines. Revts. Investinations. 3171 (1932). (5) W a r r e n , . T . E., and B o d e s , K. W . , ‘ C a n : Dept. Mines, Mines Branch Pub. 737-3 (1933). RECEIVED September 12, 1936. Presented under the title “Apparatua and Method for Continuous Hydrogenation Tests on Coal” before the Division of Cas and Fuel Chemistry, Symposium on Coal Hydrogenation, at the 92nd Meeting of the American Chemical Society, Pittsburgh, Pa., Qeptember 7 to 11, 1936. Published by permission of the Department of Minei, Canada.
Chemical Foreign Trade in 1936 Healthy Gains Continue‘
I n t h e f o r e i g n trade review ITH the general increase published in these pages last yearz in business activity in t h e s t a t e m e n t was made that 1936, a n y t h i n g b u t a “considering the 1923-25 trade as c o r r e s p o n d i n g increase in the a f a i r a v e r a g e , our exports of traffic in chemicals and chemical c h e m i c a l goods are now within wares between the United States sight of a normal level. Another and foreign countries would indeed have been surprising. But OTTO WILSON year such as the last and they 3025 Fifteenth Street, N. w.,Washington, D. c. will have reached practically the there was no occasion for such value of the annual exports in that surprise. The trade came up to period.” As Table I shows, the the end of the year with satisfactory increases in both imports and exports, the outgoing com1936 gains in exports were sufficient to carry the trade up t o and beyond the level mentioned. Even remembering that normodities being valued a t $116,902,000, or 13 per cent more than in 1935, and the incoming trade reaching a total of mally this trade would have shown a regular annual increase $79,975,000, about 16 per cent more than in the previous year. in the decade since 1923-25 had there been no depression, The somewhat larger gain made in the import than in the it is still not unreasonable now to speak of a full recovery in our chemical exports as an accomplished fact. The outexport trade corresponded to developments in the general foreign trade of the United States, in which exports of domesgoing trade, however, still remains about one-fourth below the high level of 1929, and our chemical imports are less than tic produce registered a gain of about 8 per cent over 1935 60 per cent of their value in that abnormal year. and imports for consumption a gain of 18 per cent. For ihe chemical trade the higher totals of 1936 represent one more step in the process of working back to a state of TABLIZ I. U. S. FOREIQN TRADEIN CHEMICALS BY TOTAL commercial health from the depths of the depression. The VALVES(IN THOUSANDS OF DOLLARS) low point in the trade was reached in 1932; since then imPeriod Imports Exports Period Imports Exporta provement has been steady and continuous. Handicaps in 1923-25 (av.) $120,191 $116,267 1933 $69 287 $76,771 1936 such as the maritime strike in the last quarter of the 1929 144062 151 992 1934 65:117 92,565 1930 112:070 127:770 1935 68,716 103,092 year and a continuation of the extreme uncertainty in the 1931 82,738 100,027 1936 79,976 118,902 1932 47,852 70,348 political situation abroad had their adverse effects, especially on particular commodities, but were not enough to prevent encouraging gains in the trade as a whole. How far the increase in activity was due to the new trade I. Chemicals and Related Products treaties and how far to a general stimulation of manufacture The foreign trade gains of 1936 were not very evenly diand domestic business can hardly be estimated until devided among the various great groups of chemical commoditailed figures of the trade with separate countries are availties. All classes shared in the increase in export values able. 1
All 1936 figures are preliminary.
2
March, 1936, pages 304 to 308.
