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T H E J O U R N A L OF 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 M I S T R Y
color industry. With the increasing demand for rectified benzol for motor and other industrial purposes in England, refining plants were erected; b u t even now they are not always operated with the scientific exactitude characteristic of the majority of German industrial organizations. h-umerous samples of so-alled motor benzol when distille-d a t ioo” t o 110’ C. leave a fair proportion-sometimes as much as 5 per cent-of dark colored constituents. These should have been eliminated in the washing operations, as undoubtedly their presence has a deleterious effect when the benzol is ultimately used in motor engines. GERMANY’S ARTIFICIAL FERTILIZERS Under this title appears in the 2. Vw. deut. Ing.,58 (1914) 1443, an article on the present importance of the fertilizer question in Germany. Three substances are considered : potash, nitrogen and phosphoric acid. As far as potash is concerned, there is *no doubt of Germany’s superiority over the rest of the world, but conditions are not so favorable as regards nitrogen compounds from natural sources. T o overcome this deficiency has been one of the aims of German industry, and as a result the production of ammonium sulfate from the distillation of coal in gas works and coke ovens reached the total in 1912 of 492,000 tons, which far exceeds England’s 379,000 or America’s 151,ooo tons. As a result, the nitrogen used in Germany has more and mere been supplied by ammonium sulfate and correspondingly less by saltpeter; rgog was the first year in which the consumption of the former exceeded t h a t of the latter, and in 1912 d e ratio was about 8.7 : 7.8 in favor of ammonia. This comparison shows, however, t h a t large amounts of Chili saltpeter are still being used, and t h a t any sudden drop in the supply of this salt, like t h a t caused a t present by the requisitioning by the government of the supplies on hand, must cause disturbance. This condition can be relieved by drawing on the surplus stored by the Ammoniaks-Verkaufsverbande. The coke ovens are still working to full capacity, so t h a t ammonia is being produced in large amounts, but since their continued activity depends on a continued demand, while their best customers, the iron works, have greatly limited their output, other markets for coke must be found. The representatives of the fertilizer industry, therefore, in a meeting on September 18th emphasized the necessity of substituting coke for coal in every branch of industry where it could possibly be done. To the processes of ammonia recovery from coal distillates must be added the various new processes for the fixation of atmospheric nitrogen. Those developed b y Frank-Caro, Birkeland-Eyde, Schonherr and Pauling have the advantage t h a t the production of fertilizer is their chief aim, and t h a t their output, when the prerequisite conditions are fulfilled, can be increased according t o demand without regard t o other circumstances. However, their output has not yet grown to sufficient size t o influence the market t o any extent. I n case the war is of long duration, the Germans claim one advantage in the fact t h a t a new process has been recently developed which will permit t h e nitrogen production together with the coke production t o be established on a yet broader foundation. This process, that of Professor Haber is one for the synthetic production of ammonia from nitrogen and hydrogen, and is especially characterized by cheapness and practicability. Both facts have led t o the fear, expressed in various circles, that the introduction of this process will bring about a serious drop in the price of ammonia, and already proposals have appeared in technical gas journals’ looking t o the working u p of the gas washings for other products than ammonium sulfate. However much a n injury t o the coal distilling industry is t o be regretted, from the point of view of the general welfare of the Jour. Gasb.-Wasserw., Aug. 29, 1914. p. 840.
V O ~7. , NO,I
German Empire, it is very satisfying to know t h a t the possibility of developing this process insures against a n ammonia famine. As for the third substance, phosphorus in the form of bone meal, calcium phosphate, etc. (guano is used in ever lessening amounts), it is well-known that the phosphorus-containing substances hitherto imported into Germany have been successfully replaced by the Thomas phosphate meal, a by-product of the Thomas steel works. The German Thomas steel industry is the greatest in the world, so t h a t Germany should be independent of the rest of the world for her phosphorus supply as long as these works are in operation. T H E THERMAL PROPERTIES O F STEAM Until ten or fifteen years ago steam-tables, based on Regnault’s experiments, which were for the most part made before 1847, sufficed for all the needs of the practical engineer. The introduction of the throttling calorimeter for the estimation of the quality of steam had, however, led to doubts whether the accuracy of Regnault’s results was as great as had been assumed, and these doubts were confirmed when the increasing use of superheated steam showed in many cases gains substantially in excess of the theoretical. Further researches, both theoretical and experimental, on the properties of steam were accordingly undertaken in many countries, and led to the publication of new steamtables, such as those of Marks and Davis, or the new edition of Professor Peabody’s tables, which fully satisfy the present requirements of engineering practice. Further experimental data have, however, been secured since the publication of these tables, and a very complete discussion of the thermal properties of steam, in which cognizance is taken of these newer results, has just been published by Professor G. A . Goodenough.’ In this pamphlet [Engineering (London), 98 (19x4), 6241 the whole of the available data is brought into consideration and new formulae established, which, while fitting the experimental results with great accuracy, are also consistent with each other and with thermodynamic principles, a matter of which Professor H. L. Callendar seems to have been the first to recognize the importance. The relation found between the pressure and temperature of the steam is as follows: log
p
= 10.5688080- ___ 4876’643 - 0.0155 log
+
T
-0.00406258 ‘ I ’ 0 . 0 0 0 0 0 4 0 0 ~T2 ~~ - 0.00002 10 - I O ( “ 2 ) 2 t-370
[
T
+ (7&3] I
where p is the pressure in pounds per square inch, and T the absolute temperature in Fahrenheit units, while t is the temperature in Fahrenheit degrees. The absolute zero is taken as - 459.6’ F. For the specific volume of the steam Professor Goodenough gives the expression : v - 0.017 = 0.59465
T C P - (I f o.og~zg.\lp)T4 ~
where v denotes the volume in cu. f t . per lb., and log CI = 10.82500. The “heat content” of steam a t different temperatures and pressures is : 23583 i = 0.320 T 0.000063 T2-
+
where log
ca
T
I _
=
10.79155
The entropy of superheated steam is given by the relation: 1 “Thermal Properties of Steam,” by G. A. Goodenough. of Illinois ”Bulletin. London, Chapman a n d Hall, Limited. cents.)
University
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