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-,y L a ~ ~ ~ b . , I ~ d n g ( "SGll compounds has been brought about b y t h e partial hydrolysis of t h e proteins contained i n t h e various .trade wastes used i n t h e manufacture of t h e fertilizer. When proteins decompose through n a t u r a l conditions, be t h e y in t h e soil or out of i t , a certain amount of hydrolysis of t h e proteins takes place a n d if t h e decomposition is allowed t o proceed long enough under proper conditions complete hydrolysis will result. The principle involved in making t h e nitrogenous #material in t h e soil available a n d in increasing t h e availability of low-grade nitrogenous materials by factory t r e a t m e n t is therefore t h e same. I n other words, t h e general chemical principle t o be applied in making available t h e nitrogen of low-grade fertilizers, t r a d e wastes, etc., is t h a t of complete or partial hydrolysis b y a n y suitable means of t h e proteins contained in t h e wastes. Partial hydrolysis of proteins m a y be accomplished b y means of heat, boiling, steaming, heating under pressure; both partial a n d complete hydrolysis m a y be obtained b y treating with strong acids or alkalis, either in t h e cold for a long time or heating t o a high temperature, t h e extent of hydrolysis depending on t h e several conditions. An examination of t h e patent literature shows t h a t all of these means have been proposed for t h e t r e a t m e n t of waste materials, although t h e actual chemi'cal principle of hydrolysis involved in t h e t r e a t m e n t is not considered. Also, i n a number of processes in actual use, various of these treatments are practiced, resulting in different degrees of hydrolysis of t h e original proteins. While t h e availability of t h e nitrogen of a fertilizer depends on t h e substances i n which t h e nitrogen is contained, it also depends on t h e extent of hydrolysis of t h e proteins used in t h e manufacture. It may be s t a t e d t h a t in general t h e more extended a n d final t h e hydrolysis t h e more available t h e nitrogen of t h e compounds formed, since, as has been shown, t h e final products of hydrolysis are utilized b y t h e plants as such a n d are at t h e same time more readily changed into ammonia b y bacteria, etc., t h a n are t h e intermediate compounds produced b y partial hydrolysis. *LI"I
I
S UM MA R Y
T h e base goods used as a t y p e of processed fertilizer
w i n g principally t h e products or prirlidry p r o w l 1 uLcomposition, together with a small amount of a proteose-like compound which has persisted. F r o m t h e sample of base goods were isolated t h e following nitrogenous compounds : two purine bases, guanine a n d hypoxanthine; t h e three diamino acids, arginine, histidine, a n d lysine; a n d two monoamino acids, leucine a n d tyrosine. A proteose-like compound was also obtained a n d i t s general n a t u r e established. By means of t h e Van Slyke Method t h e approximate proportions of t h e different forms of nitrogen contained in t h e fertilizer were estimated, a n d t h e extent of t h e hydrolysis of t h e original proteins was determined. It was also shown b y this method t h a t t h e proteose-like compound was composed of acid amide radicals, diamino acid radicals, especially lysine, a n d monoamino acid radicals, particularly t h e monoamino acids which contain non-amino nitrogen. T h e question of t h e availability of nitrogen is discussed, a n d from a consideration of t h e amount a n d t h e physiological action on plants of t h e different forms of nitrogen present i n t h e fertilizer i t is concluded t h a t t h e water-soluble nitrogen of this fertilizer should have a n availability equal t o or greater t h a n t h e nitrogen of dried blood, or other high-grade fertilizers. These results are i n accord with t h e results obtained b y t h e plant method of determining availability. T h e general chemical principle which underlies t h e method for rendering available t h e nitrogen contained i n most t r a d e wastes, which are t o be used as fertilizing materials, is shown t o be either partial or complete hydrolysis of t h e protein of t h e wastes b y a n y suitable means. T h e more complete t h e hydrolysis t h e more available t h e nitrogen in t h e fertilizer becomes, since t h e products of complete hydrolysis of proteins are not only utilized b y t h e plants themselves as nutrients b u t t h e y are more 'easily ammonified when placed in t h e soil t h a n are t h e more complex compounds, such a s peptones, proteoses, a n d t h e proteins themselves. BUREAUOF SOILS
U. S. DEPARTMENT OB AGRICULTURE, WASHINGTON, D. C.
LABORATORY AND PLANT PURIFICATION AND STERILIZATION OF AIR' By S. BORX AND WM. F. CARTHAUS
Received h'ovember 16, 1914
I n considering t h e question of air, we have t a k e n i t up mainly from t h e standpoint of t h e fermentation 1 Presented before the St. Louis Section of the American Chemical Society, June 8, 1914.
industry, b u t t h e methods employed here could easily be extended t o other fields such as t h e ventilation of hospitals, schools, public buildings a n d factories. Air is one of t h e most important factors in t h e brewing process, a n d a s sterile air can be obtained b y \ none of t h e ordinary methods employed for purifying
M a r . , 191;
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
111-STERILIZERFOR AIR I N FERMENTATION DEPARTMENT PERMANGANATE TANKAND HIGHPRESSURES T E A M BOILER
FIG.
This object can be accomplished more easily a n d with a greater degree of sterility with air t h a n b y a n y mechanical device. All t h e above air used i n t h e fermenting department must, as i t comes i n direct cont a c t with t h e beer, necessarily be of a high degree of purity, a n d we resort t o t h e following method of obtaining i t in a sterile condition. I t is a common statement in t h e literature t h a t all t h a t is necessary in order t o obtain sterile air, is t o pass i t through a cotton filter. We have never been able t o obtain sterile air 'by such a simple method although we have made quite a few experiments along this line. The air is first passed through a series of drums tightly packed with cotton, which are sterilized a t regular intervals i n the laboratory. After passage through t h e cotton, i t is t h e n sprayed through a t a n k filled with a solution of potassium permanganate a n d from there i t is passed through a sterilizing a p p a r a t u s which consists of a high pressure boiler filled with a series of baffle plates a n d kept a t a temperature of a b o u t 2 6 5 ' F. Here t h e air is intimately mixed with steam a t a pressure of 1 2 5 pounds, a n d i t remains i n contact with this steam a t this temperature for about fifteen minutes. It t h e n goes through a series of condensers for cooling i t a n d condensing t h e moisture, through a small cylinder filled with potassium permanganate (a sight glass, not a sterilizing apparatus) a n d is t h e n passed into t h e beer.l T h e advantages of this method of sterilizing over a n y washing method can readily be seen when we con1
This apparatus was designed and built in our shops in 1913.
235
sider t h a t no matter how small a bubble m a y be, t h e . volume of t h e interior is considerable compared t o its surface area so t h a t only a small p a r t of t h e bubble comes in actual contact with t h e washing or disin fecting liquid. However, in t h e very intimate mixt u r e of air a n d steam all parts of t h e air are reached. The air for t h e fermenting cellar a n d storage cellars (which does not come in direct contact with t h e beer) is purified as follows: As t h e temperature of t h e fermenting a n d storage departments is generally far below t h a t of t h e outside air. we use a unique a n d very simple system of ventilation. Cold air is heavier t h a n warm air and hence sinks, especially if t h e air contains large quantities of carbon dioxide such as are normally present in a fermenting d e p a r t m e n t ; so, a t t h e upper p a r t of t h e fermenting department we have installed a series of cotton filters and a number of galleries filled with ammonia coils, which cool t h e air a n d precipit a t e a n y moisture which may be i n i t . At t h e lowest floor we open a window or door. The result is t h a t t h e cold air rushes through t h e open door a n d t h e suction created draws in t h e outside air through t h e filter a n d coils mentioned above. The actual draught a t t h e lower level is strong enough t o blow out a candle. The following method is used for testing air: Sterile Petri dishes are provided with a layer oE sterile meat gelatine agar or wort gelatine agar; t h e former is a suitable medium for bacterial growth a n d t h e l a t t e r for moulds a n d yeast. If we desire t o test t h e air in a room or cellar we simply expose a plate for a definite length of time, e . g., one minute, a n d examine t h e contents developed after 7 2 hours. However, testing t h e air i n pipe lines, such as we
FIG
IV-SIGHT
GLASS U S E D TO I N D I C A T E AMOUNT O F PUMPED XNTO WORT
AIR BEING
use throughout t h e plant, offers more difficulty. We have placed small stopcocks a t various points in our air lines b u t we found t h a t b y opening these a n d exposing a Petri dish near t h e m we never could get a sterile plate. Investigation showed t h a t a siphon was
T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERIiVG CHEMISTRY
236
created b y t h e outrushing air which dragged microorganisms f r o m t h e surrounding air onto t h e plate. In order t o eliminate this undesirable effect we tried fastening funnels of various sizes b y means of a rubber attachment t o the cock. We found t h a t a funnel whose circumference was exactly t h a t of our dish gave us t h e best results so this method has been adopted for taking air samples rapidly throughout the plant. LABORATORY OF THE W&l. J. LEMP BREWINGCOMPANY ST. LOUIS .
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AN ETHER RECOVERY TUBE By J. M. PICKEL Received December 19, 1914
I n fat extractions with the Knorr flask, i t is.custom a r y t o recover the ether b y removing the extraction t u b e and putting in its place a test tube. The accompanying sketch shows an arrangement hy which this exchange of tubes and a t t e n d a n t loss of time and ether are obviated. During t h e extraction t h e ether drops from the point C into t h e funnel d , which conveys i t into t h e extraction t u b e B. When the extraction is finished, t h e other side of the tube A is brought under t h e point C ; this is E accomplished without interrupting the distillation, by merely turning t h e Knorr flask. The funnel, which A is made of either glass or metal, has the peculiarity of being a half funnel, covering b u t one-half t h e m o i t h of the t u b e A t o which i t is fused a t its lower end only. The extraction tube B need not /e be over 4 or j cm. long t o accommodate a n ordinary charge ( 2 g. subB stance) and instead of two holes near its top for the circulation of vapor, two V-shaped notches filed in its edge are equally efficient. The inside diameter of the standard /&e cylinder E is about 3.2 cm. ( 1 . 2 5 inches); t h e outside diameter of -4 should therefore he not less than 2 . 7 cm. ( 1 ~ / 8 inches). The length of A should be t h e greatest possible without touching t h e point C when i t is revolved. The inside diameter of the necks of t h e Knorr flasks need not, a n d should not, be less t h a n 2 2 or 2 3 m m . I n t h a t case, the extraction tube can be dispensed with, and in its stead a standard paper thimble, 1 9 m m . diameter, used. The thimble is placed inside the neck of t h e Knorr, its lower end reaching down t o within I cm. of t h e surface of the ether; i t m a y be conveniently supported in t h a t position b y a small copper wire permanently wound around i t , ends of t h e wire on opposite sides resting on top of t h e neck of the Knorr. T h e space gained in the cylinder E b y t h u s sinking t h e extraction thimble into the Knorr, makes i t possible t o give added length and capacity t o the recovery t u b e A . Moreover, the extraction takes place in ether
c
Vol. 7 , No. 3
vapor, a t practically t h e boiling point of ether, and i t is claimed t h a t an extraction in t h a t case is complete in about 4 hours instead of t h e usual sixteen. NORTH CAROLINA DEPARTMENT OF AGRICULTURE RALEIGH
______ A CONVENIENT FORM OF WEIGHING PIPETTE By A. T. MERTES Received January 27, 1915
For conveniently and accurately weighing o u t quantities of glycerine such as are used in the determination of glycerol b y the acetine method, the writer devised t h e form of apparatus shown. It is convenient a n d useful for weighing out oils for t h e determination of t h e Iodine Number. especially those oils having a high iodine absorption, and which require an accurate weight. For Koettstorfer and Reichert-Meissl Numbers, the pipette may be calibrated so as t o assist in delivery of t h e proper amount of fat or oil. The pipette can be made b y a n y one having a little skill in glass working. The writer uses a n old I O cc. pipette and fuses a glass stopcock t o one end. T h e other end of t h e bulb is draivn out and bent into a hook as shown in t h e sketch. I n order t o fill the pipette, a rubber t u b e is attached t o t h e upper end and t h e desired amount of t h e fat or other substance sucked up into i t . The stopcock is then closed, t h e delivery t u b e wiped off and the pipette suspended b y t h e hook from a balance and weighed. 6537 WOODLAWK AVEXUE,CHICAGO
A FILTER-PIPETTE FOR ETHER B y J. 34. PICKEL
Received December 17, 1914
The accompanying illustration shows a device for filtering ether without waste and simultaneously de-
B
livering it in requisite measure into fat extraction flasks.
