Ammoniation of Peat for Fertilizers R. 0. E. DAVIS Fertilizer a n d Fixed Nitrogen Investigations, 13ureuo of Chernistry and Soils, Washington, D. C WA1.TI3R SCHOLL A N D
HE first forms of EcrtiThe tr~alrrirridqf petit zailh liyriid arnnioriia is lisers or soil anicridments tent. curried out urider varying corrditions of temperam r e organic residui:s of There have been a number or ture, pressure, time of treutrnent, arid rnoislure various sorts wliicli owed their attempts in the past to render present; the qffrct qf these fuelors or1 the urnounl effectiveness in soil iniprovetlie nitrogen in peat a \ ~ ~ i l a bfor le of nitrogen ublairvd in the product i s sludied. plant use, or tlirough prnecssing riieiits partly at least to tire nitrogen contained i n tliein. Ortoreeover thenitrogen from peat. A riitrogeri, conlenl is obluined in the pruduct as ganic nitrogemus r u a t e r i a l s Recently several patents have liigh as 21.7 per ceiil. 7'1ii.s nitrogen is preserit !)are continued to bc; used in ferbeen issued on processes involrpartly in a ~~~aler-soluble jr,rni arid purtly watertilizers arid l i n e plnyed a large ing tlie use of ammonia in treatirisolnhle. According to cherrT,icuE tesls 70 to part in the comlmition of uiixed ing peat, or inaterials of plant 95 per wnl r!f the n,itrogeri i s active, bid drfiriilr fertilizers in this country. In origin with a vier>- t o oiititiriiug recent years, liowerer, devclopa fertilizer material or a nit.rogeirijorrriiilim (in its ucuilabilily to plunls toill be irieiits i n the fertilizer industry u o u s foodstuff. Erastirus (4) oblnirrrd only liiroiigh zvgdutiw lests. lhave cliangcd sonie\s!iat the reo n h e a t i n g edrbohydrates of The ~iliysicnlpropertirsqf thr mulerial ure such lations of org:~nic materials to plant origin such as u.nod, sugnr, us to rt-rornrrimd it .for icse irr j r r l i k r r s . Ecomixed fertilizers Tlie nnioiint cellulose, etc., under prrssure at riomic corisidrrutioris iridicule the possibility of of 1,igIi-gmde organic nitroge300" C. obtained a p r o d u c t nous materials available for w e containing up to 20 per cent its prodiccliori coninrercia,lly. n i t r o g e n . E h r e n h e r g a 11d as fertilizers has been eraduallv iiiminisliing, and at times the Heirnan (8) heated nmtcrials of price paid for organic ziitrogcri has been several times greater plant origin vegetable materials urider pressure with ainthan that paid for inorganic nitrogen. nioniii and air or other gases containing oxygen. Einploying The desirability of utilizing snme abundant sonrix: of or- tcmperaturcs of 200' t o 250' C. and presrurrs of 50 atmosganic substance as n carrier of the c h a p nitrogen now being gliercp, they obtairicd a product with iiicrensed nitrogen produced as amnioiiia by nitrogen fixation processes led to content. Caro and Frank (2) subjeckd humic acid, vegeinvestigation by the Fertilizer and Fixed Kitrogen Investiga- talile matter, lignite, or peat to oxidation at 50' t o 300" C. tions Unit of available materials suitable For sucli use. Peat, aiid then passed ammonia over tile product and obtained a wood waste, and various farm, forest, and industrial waste nitrogenous material suitable for fertilizer. Later patents organic products were considered from the standpoint of their were obtained by tlic same authors (2) involving some modiabundarrce, arailability, and desirability as possible carriers fications in t,lie process of treatment. Vortmair (?)produced of nitrogen. Peat seemed to meet the requircnients most an organic nitrogenous fertilizer by passing nitrous gases completely of ally of the materials considered. I t occurs in rnixed with oxygen, air, or steani into vegciahle or animal large quantities and in commercially workal~ledeposits at material, axid peat was one of the materials employed. Walwid el y d i s t r i 1.1 u t e d points tan and Gardincr (8) treated tlirougliout tlie enstern part of peat with a liquid nrelt of pliosthe United States, and t.o a p h o r i c acid aiid monopotasless abundant degree in tlic Far siurn p h o s p h a t e , and then added a~rinioniat o ruwtralize West. Such depositsare found froni X i n n e s o t a to Llaine, the free acid. The iritrogeo of the peat as rendered availalong the Atlantic Const, and able, and a mixed fertilizer of frorrl Florida to Texas. It is estimated tirat the amount of exccllent physical proi)erties obtained. In no case, liowp e a t corr~mercially available ever, has any publislied account in the country is in been given of the experiiueni,illion tons (ti); about linlf of tal evidence r e g a r d i n g t h e this is in Minnesota, and over preparation of the materials i 0 per cent of the remainder is i n hliclrigdii, Wiseon,3iri, and described. Florida. Of this m a t quantity Pnoc~saOF ~ M M ~ N I A T I ~ N of material a relatively insignificant amount is utilized; its Several samples of natural p e a t selected f o r treatment irioat iiriportnnt w e i with ammonia were furnished ditioner or filler in mixed fer; tilizer. and in nreenbou,?cs or tlirnunlr t,lie kiudness of A. It. crtlier speeial cultural conditions for mixing with sui1 to pro- Jlaeliiio~eki-Stokesof this bureau. They were a Germail duce suit.able physical conditions for plaitt growth. moss peat, Florida lily peat, Ohio reed p a t , and a conimeiFeustal alii1 Dyers of the Soils Unit of this bureau (5) in cia1 peat from Capac, Mich. Tlie peat \vas loaded into an iin investigation of tilt: ~lnxrinl~o.itionof raw and treated peat autoclave with anliyiiious liquid animoiiia in I ntioa of amin the soil, heated peat wit11 atninoniuoi Iiydroxiile under monia to peat varying froin 0.17 to 2.67 by uciyht,, but gcnautoelavc conditions, a i d obtained a product, witli verjr erally in proportion of one to one; t l i c c l o d autoclave was 1074
I N D 0 S T R I A I,
Octolwr, 193.3
A N 1) :E Y G 1 N I*; I3 1% I N C C f l E VI 1 S T I< Y
heated exteriially either by placing in an electric oven ox by ari electric heater surrounding the autoe1m.e. After a period of heating, the autoclave was cooled, the pressure released, iind tlie produet rcniovcd and exposed to the air until evider1c:e of ammonia liar1 diXIppeRred. TIN!proiliict removed from the autoclave was found to contain nitrogrli in varying amounts up to 21 per cent 011 tlic dry ba.sis. A t least four
1075
In Figure 3 and Tablc I is sliowii the effwt of treating the four types of peat mentioned with anhydrous ammonia, at tcniperatures ranging up to 300' C. The peats as received containing tlie percentage of water indicated were placed in a steel autoclave, and a.n cyual quant,ity of liquid ammonia was addcd. The autoclave was closed and placed in an oven at tile desired temperature for 24 houm. It was then cooled by placing in crushed ice and water, tlic pressure was released and tlie product was removed and exposed to the air aiid suction to remove free ammonia. The results arc on the dry basis. The original content of nitrogen in tlie four peata varied from 0.8 to 3.2 per cent. Peats A and I+ only were tested a t 50" C., and p a t s A and C only a t 300" C . These rcsults slrow the marked irifluenee due to increase in temperature, as well as differeiicc due to the type of peat.
TAXLS I. T i i e a r x ~O~P~ P w r s AMMONIAAT VARIoUS
I,IWID A N I Z Y D I I ~ U ~
WITL(
'rEMPEXATUKES
TOT**.N 03
TaMP. a
"est
c. 50
125 180 235
300 Obiuroed pent (El)
50 125 180 255
Florida lily mat
FIGUAE2.
Borrn OF 6 LITE^.^ CAPACITY FOR 1'x~:pawrn.cAMMOX~.AT~.:~ I'SAT
(C)
vnriublcs liam lieen foulid to influence tlio amount of nitrogen obtained in t.he final product-rraniely, temperature, pressure, xatcr, and time of treatment. In adrlit,ion, some study has been made of the action of different types of peat, of tire prcvirm treatment of peat, of other sihstanccs m-l'liicii may act catalytically, and of the pI~[value of the peats, but sufiicient data on most of theee lime not been obtained to include thern in this palm. Figures 1 nrid 2 illustratc the types of apparatus employed in the ammoniation experiments. I i i Figure 1 tire shown severid srriall buinbs ranging in capacity from 75 to 900 cc., in which about 15 to 100 griims of the ammoniated prudriet can be prcpnreci. Class thimbles are loaded with peat niid inserted into bhe bomb, which is closed as shown. desiwd quuntit,y of liquid ammonia is introduced into the d bornh trom the small oylindm, shown at the Icft, by conng it to R valve in the heed of (.he bomb. w e 2 shows a bomb of about (i liters cqxrcity ia which 1.5 t.0 2 pounds (0.68 to 0.91 kg.) of iimmorriateri peat c t ~ nb~ prep:ired. The h a d of tho bomb is provided with thermucouple wdl, diqhragrn safety valve, pressuro gage, and irilct pipe and valve for introducing liquid riminonia from the special iimmoniia cylinder supplied with calibruted sight gage, shown i n the upper right, comer. A swingiuE mine is pmvidcd for haiidiing the h o d of the autocliLvo. At the bottom of Figure 2 is shown t.hP rloctric Eurnnre irr n loivered position. This is raised t o enclose the lower
50 Reed peui, I3 (8.1%
N)
125 50
24
72
120 24 7% 120 24 72 120
3.45 3.70 4.65 11.50 12.09 12.71
2.15 2.26 2.62 6.01 7.15 7.44
7.86
4.59
8.55 9.17
4.77 4,87
125 180 255
3w
PHOD.
U*sm
Nrrnoom *a:-
--TOTAL
DCT Dnr Active
N
AeI.ive
HIO-sol.
HzO-
ineol.
Inactive
%
%
%
%
%
3.47 6.35 11.63 19.42 21.82
72.7
34.6 67.5 68.9 70.6 78.4
27.3 10.7 7.2
96.2
38.1 21.8 23.9 22.8 17.8
6.70 8.05
73.0 88.5 97.3 91.8
19.5 25.4 25.0 30.8
68.5 63.1
72.3 61.0
27.0 11.5 2.7 8.2
90.4 87.6 89.9
20.0 23.4
18.2
72.2 67.0 66.5
9.6 12.4 10.1
12.22
15.62
7.82 10.42
13.g0 14.02
89.2
DP.8 9.1.4
..
..
..
6.6
3.8
..
hlicliieail peat (D)
125 7.44 93.5 17.1 78.4 6.5 180 12.76 93.4 29.2 64.2 6.8 255 16.28 95.5 26.9 68.6 4.5 Oiiainal nitrosen prenent in A. 0.83 per oeat; Y, 3.14; C . 3.2; 11. 1.8.
Tire t,imt: of treatment was tested ill tlie saiiie way and the time exkended at given temperaturcs to I20 hours. Results are given in Figure 4, and Table 11, sliowing the influence of time at several temperatures with two types of peat. These demonstrate that, after 24 hours under the conditions impose4 the curve flatt.eiis out and there is increase of only about one per ceirt in the interval from 24 to 120 hours at the temperatures employed. The highest temperature used here xas 125" C. It is probable that at higlier temperatures the rntc of reaction is more rapid, and a considerably higher value lor the amount of nitrogen in the product is obtained in a shorter time. In Yigure 5 arid Table I11 are stionn the results of several experiaients with different amounts of water. Only one peat (Capac, Midi.) was used. The six curves sliown are for t.hc ratios of an~lrioriiato peat indicated. herensing the ratio increases the nitrogen colittant of the product, a i d at iilmut. 10 per ccnt water the curves reach a maximum, d r o p ping off wit11 higiier moisture content. In Fipm 0, using
1.s0
1.44 2.03 5.49
4.94 5.27 3.27 5.77 4.30
120 1.14 1.55
5.08 6.25 11.40
3.05 3.25 3.39
62.3 61.1
56.4 62.3 59.1 58.6 58.4 55.8 53.1
72.5 69.8 77.0 62.0 92.6 02.5 80.4 82.2 83.9
y7.5 do.2 23.0 8.0 z.4
f.5
19.5 17.8 16.1
24.0 22.2
17.8 27.3 26.0 24.7 40.0 36.7 34.3
55.8 50.5 59.2 84.5 87.7 87.3 06.5
68.1 69.6
INDUSTRIAL
1076
AXD ENGINEERING CHEMISTRY
data in Table 111,the results are given for variation in pressure using one type of peat and a temperature of 180" C. with a treatment lasting 24 hours. This shows that a rapid rise of nitrogen content occurs with the first increases in pressure, but beyond 60 atmospheres the increase in nitrogen is slow. Table I11 shows that the yield of product varies from 55 to 90
Vol. 25, No. 10
Additional experiments on one type of peat at atmospheric pressure with varying temperature showed that considerable nitrogen is absorbed by the peat, increasing with the temperature (Table IV). The reaction of the original peat apparently has little to do with the amount of nitrogen fixed in the product. The determination of pH was made on a water extract obtained from treating a sample of peat with five times its weight of water. The acidity exhibited, of course, is due to soluble materials in the extract. Since peat, oven-dried a t 105" C., on which ammoniation was carried out, is not bone dry but releases considerable water when heated t o 180" C., a relation between the p H of the peat and the amount of nitrogen fixed was suggested. The results of tests on several peats are given in Table V. 30close relation is shown from this series. The sample with the highest p H has much the lowest amount of nitrogen added by ammoniation. Sufficient data have not been obtained to attribute any causal relation for this to the alkaline peat. TABLEV. RELATION OF PH TO TOTAL NITROGEN ADDEDTO PEATSBY AMMONIATION ITROGEN
-N1
SAMPLEPH Original 0
,a
50
25.9
IW
Trmo
300
'C.
A
FIGURE3. TREATMENT OF PEAT WITH ANHYDROUSLIQUIDAMMONIA AT VARIOUS TE~ERATURES
1;
per cent of the dry peat. I n the method of treatment this is lost through evaporation as the ammonia vaporizes. A considerable part of this is water, but the presence of other substances is being investigated.
B D E F C H N R V
3.7 3.9 4.1 4.5 4.7 5.8 6.0 6.0 6.5 7.1 7.3
Total
-
-
Added
%
%
%
0 83 0.91 3.10 1.81 1.81 2.69 3.30 3.97 2.96 3.14 3.30
11.43 10.50 12.12 12.66 10.21 11.71 10.42 12.05 11.72 11.60 8.51
10.60 9.59 9.02 10.85 8.40 9.02 .I2 8.08 8.76 8.46 5.21
,
DESCRIPTION OF PE.AT
hlumui
CHARACTER OF THE PRODUCT OF MICHIGAN PEATWITH DIFFERENT The availability as plant food of nitrogen in the ammoniTABLE 111. AMMONIATION AMOUNTSOF WATERPRESEST ated peat is of first importance if it is to be employed for PRODUCT fertilizer purposes. While only actual field tests in growing RATIO Yield PEAT NHSTObased Total h a . plants can answer finally the question of availability, there H20 I N (OVENCHARGE DRY on dry N(dry PRESPEAT DRY) NHJ H20 PEAT peat basis) TEMP. SURE -~ are laboratory tests provided by the Association of Official V," , Grams Qrams Grams % % * C. Atm. Agricultural Chemists (1) for determining the activity of ni11.0 6.99 181.1 ~
~
~
0
15.0 15.0 15.0 15.0
2.5 5.8 12.3 36.0
0 0 0 0
0.17 0.39 0.82 2.40
87 93 60 73
8.87 9.00 10.21
180.3 180.7 179.9
41.8 62.3 218.5
loa
13.5 13.5 13.5
4.6 17.0 33.9
1.5 1.5 1.5
0.34 1.26 2.51
67 85 84
7.15 10.69 9.64
180.4 179.3 180.4
14.9 115.0 168.0
15.6 15.6 15.7
0.32 0.64 1.26
84 87 90
9.80 11.17 12.85
180.1 178.0 180.1
59.4 96.3 161.3
6.0 80 80 23.9 basis
0.74 1.67 1.67 2.67
73
7.98 10.04 9.23 11.29
181.1 170.6 175.2 180
37.5 106.9 130.5
140.0 140.0 141.5 40
a
45 90 178
9.0 6.7 1 2 . 0 200 1 2 . 0 200 35.9 96 Per cent water on wet
.,
58 55
...
Peat A when treated with ammonia a t 1500 pounds pel square inch (105.5 kg. per sq. em.) pressure a t 25" C. for 24 hours gave a product containing 3.30 per cent nitrogen, indicating that even a t room temperature 2.4 per cent nitrogen is added by treatment with ammonia, but that increased pressure does not exert as great influence as an increase in temperature.
Time
," Hours
OF PEATWITH LIQUID FIGURE4. TREATMENT AMMONIA AT VARIOUS TIMEPEHIODS
trogen in organic nitrogenous materials for differentiating between those of high and low activity. These involve the use of neutral permanganate and of alkaline permanganate TABLEIV. LOW-PRESSURE AMMOXI ~ T I O N EXPERIMENTS solutions for releasing ammonia from the material. By defiN IN NHI PRESWEIGHTPRODUCT nition the water-insoluble nitrogen in fertilizers showing an TEST=PEATb Hz0 TIME RATE S U R E TEMP C H ~ R G E(DRY) activity below 50 per cent by the alkaline method and below % Hours Cc./Mzn M m H g C Grams % ' 80 per cent by the neutral method shall be classed as inferior. 28 A 1 1 . 5 6 24 300 760 125 10 4.05 250 760 255 10 7.69 0 6 E 33 This necessitates the use of both methods before classifying 7 . 8 5 0 6 300 760 255 15 E 34 0 24 300 760 300 8.5 9.42 as inferior. The presumption is that the nitrogen of high 36 E 300 760 300 10 7 . 8 9 37 E (raw) 40 24 -. , activity is available as plant food, but this does not necessarily a Condensate from vertical condenser ran bark to charge in each case follow. By passing the test for high activity, the insoluble except one. Distillate from No. 28 collected. Nitrogen in distillate, 5.93 per cent nitrogen in fertilizer enters the trade with approval as a b Peat' A, German moa8 peat: peat E, Capao, Mich.. peat.
I N D U S T R I A L ,4N D E N G I N E E R I N G C H E M I S T R Y
October, 1933
worth while material. The original peats contain from 1 to 3 per cent nitrogen which is known to be very slowly available as plant food. This original nitrogen is part of the total nitrogen obtained in the product after treatment of the peat with ammonia. The tests referred to above indicate that in most cases all of the nitrogen is highly active. In Tables I and I1 are given results showing the total nitrogen and the active and inactive nitrogen. Active nitrogen in Tables I and I1 includes the water-soluble nitrogen and that released by treatment with neutral permanganate solution. Inactive nitrogen is nitrogen not included in the active portion. The analyses on seleral samples of the relative amounts of water-soluble and -insoluble nitrogen show from 53 to 84 per cent of the nitrogen in an insoluble form and the remainder soluble in water. Very little of the nitrogen is obtained as ammonium nitrogen when tested by boiling with magnesium oxide for 2 hours. In three samples tested, peat Aiwith 5.07 per cent contained 0.05 per cent ammoniacal nitrogen; peat A with 6.25 per cent nitrogen contained 0.64 per cent; and peat B with 8.05 per cent nitrogen contained 0.57 per cent. This ammonium nitrogen is believed to be present principally as ammonium carbamate or carbonate, as crystals of carbamate were identified in a condenser used in refluxing where ammonia was passed through heated peat at atmospheric pressure. Examination of a sample of ammoniated peat from Capac, Mich., was made to determine the general character of the nitrogen present in the compound. A sample ammoniated for several hours at 180" C. was employed for analysis. The following results were obtained: %
NITROOEN Total Kjeldahl .\mmonium Amide
NITROGEN Imide Other forme
11 13 1 33 1 12
% 2 57 6 11
The water-soluble portion of the peat was obtained by heating 5 grams of sample to boiling with 50 cc. of water, filtering through glass, and washing with 150 cc. of water. The brown solution obtained gave the following results based on the whole sample: NITROGEN Kjeldahl Ammonium Amide NOTE The analyeee uere of this laboratory.
%
NITROGEN Imide Other forms
2 30 0.44
% 0 00 1 35
0.51 obtained through the courteey of R T. Milner
The method of analysis employed may be in error owing to the complex composition of peat, but the results give at least some insight into the character of the nitrogen contained in the ammoniated material. Total nitrogen was determined by the ordinary Kjeldahl method. Ammonium nitrogen was obtained by treating the sample with concentrated sodium I
j. I,* E sa -. $e P
$6
/ 1
,
) 8
I
, 12
,
,
1
16
Per D n f
1 20
! I 28l l ,1[ I ,6 I ! 3' ' j
2.
water (Wet am*)
FIGURE5. AMMONIATIOV OF MICHIGAN PE4T WATERPRESENT
WITHDIFFERENT AMOUNTS OF
hydroxide solution and aerating to remove ammonia and the total remaining nitrogen determined by the Kjeldahl method. Distillation of the sample with concentrated sodium hydroxide solution gave ammonium and amide nitrogen. For the imide nitrogen the sample was neutralized with sulfuric acid and R measured excess of 1 3' sulfuric acid added; after standing one hour at 50" C., the sample was back-titrated with sodium
1077
hydroxide for the acid neutralized by the imide nitrogen. The value for the other forms of nitrogen is obtained as the difference between the total nitrogen by the Kjeldahl method and the sum of the ammonium, amide, and imide nitrogen obtained as described. Ammoniated peat is somewhat similar in appearance to raw peat, but it is readily pulverized and darker in color (from dark brown to black), and its density is slightly greater than the air-dried raw peat. Tests as to its value as conditioner in fertilizer mixtures have not been made, but its general physical characteristics would indicate its suitability in this respect. ADDITION OF NITROGEX BY OTHER ~ I A T E R I A L S 4 number of other materials have been tested and found to add nitrogen under conditions of treatment similar to those described. Treated for 24 hours with ammonia, a sample of lignite from Sorth Dakota gave a product containing 3.45
01
1 1
a1
m1
ii/
Ar3surc
10
zoI
a1
al
'
A m r a r p ) ~ r ex~ 10
FIGURE6 . INCREASE OF NITROGEN C O N T E N TW I T H I N C R E A S EI N PRESSURE
per cent nitrogen after ammoniation a t 125" C.; sawdust had 4.60 per cent; sulfite liquor residue with no nitrogen in original, 4.58 per cent; and leather scrap ammoniated at 180" C. for 19 hours gave a tarry product with 16.9 per cent nitrogen and a solid part with 13.7 per cent nitrogen, yhile it originally contained 5.57 per cent. POSSIBILITIES AS A FERTILIZER hhTERI.%L There is promise of several advantages in the use of ammoniated peat in mixed fertilizer and alone as a nitrogen carrier if vegetative tests show the nitrogen to be available. Its physical properties indicate that it should be suitable for use in mixed fertilizer as a conditioner, should prevent caking of the mixture on storage, and should cause it to maintain a condition suitable for easy distribution in the field. A portion of the nitrogen being present in a water-insoluble form indicates that this portion of the nitrogen will be retained for some time in the soil and supplement the more readily soluble materials. This would tend to lessen the loss of nitrogen through drainage or leaching from certain soils where heavy applications of fertilizers are employed. Although the nitrogen is active by laboratory tests, information on its availability in ammoniated peat relative to that of nitrogen in other materials employed as nitrogenous fertilizers has not been obtained as yet. Such comparisons through vegetative tests are necessary for the final evaluation of the material for fertilizer use. Tests are being started at several locations by different cooperators.
ECONOMIC CONSIDERATIONS The consideration of economic conditions is predicated on the assumption that vegetative tests will show that the ammoniated peat carries its nitrogen in an available form and that it is in other ways desirable for fertilizer use. The possibility is suggested of the commercial production of ammoni-
1078
INDbS’lHIAL AYI)
ENGlNEEIIlNG
ated peat, from the standpoint of tlie cheapness and abundance of tho miv materials alone. Peat, one of the raw materials entcriiig into the arnmoniated product, is lvidely distriliuted in conimercially workable deposits within short distances of the principal fertilizerusing parts of the country. E’reiglrt charges on the raw materials should be low, especially as liquid annnonia niay be shipped in tank cars to Incations convenient to the peat beds. I n certain locatims where p i t and phosphate rock occur close to each other, the prepwation of the raw material, it6 processing to the anrmoniated product, and its incorporation in a niixed fertilizer might be carried out. to admiitage a t the same location and iii juxt8posit.ion to an intensive fcrtiher-consuming area in whiclr organic nitrogen carriers are often preferred. The other material entering into tlie t,reated yrodnct is arnmouia, the most abundant and one of tire cheapest forms of nitrogen obtainable for fertilizer Inanufact,ure. Derived from nitrogen fixation processes and from by-product. coke ovens, it is shipped buth as anhydrous and aqua aninionia in tank cars. liefore treatmerit with annnonia, it. would probably he desirable to dry the peat to some degree. Possibilities of air drying and of artificial drying are presented. Tlie cost of preparing peat for fuel purposes was studied several years ago by the Iiureau of Mines ((i).The conclusions, based largely on the work of Canadian engineers on Canadian peat, indicated that the cost of peat fuel (air-dried, niacerated peat containing 30 per cent moisture) based on 100 working days of 10 tiours each is $4.48 per ton on board cars at siding.
C11ERIISIIIY
Vol. 2 5 , n o 10
On a W-liour day h i s it is estimated at $3.50 per ton, with full allowance for overhad and dcpredation. The cost of similar drying iii t,his country should not exceed this fignre and in many locations should be considerably reduced, especially in the warmer portions of the eonrdry \&ere the number of working days is greater. The process for carrying out the ammoniation involvcs a nunibcr of technical questions which >ire yet to be solved, but the possibility of its commercial production seems promising. Ilotti raw materials are abundant and clienp, and the proc~rssingrelativcly simple in principle at least. Many details connected with the properties arid production of aninioniated peat, are being investigated to obtain a definite pictnm of its usefu1nei.s.
I
I
~
~CITEU ~ i
t
~
~
~
( L J haaui:. Ofliaiul Agr. Chein., Oificid and Teiiliitivi Metiruda of Analysis, (‘hap. 11, p. 24, pp. 3040 (1931).
( 2 ) Cam, S.. xxid Frank, A. It., French Patrnt 689,011 (Jan. 28. 1!130): 1irit.ish Patents 347,G41 (Aiidl 29. 1!1:3Ij, arid il.iD.004 15, 1%2oj. (4) Eramius, P., German Patent 514,510 (XOY.7, 1928). ( 5 ) Feustd, I. C., end Ihrrs, K. G., Dept. Agr, Tech. Bull. 214 (1933).
(6) Odeli, W.W.,and Hood. 0.P., Bur. Mines. Bull. 253, 7, 19 (1028). , (7) l’ortman, E., German Patent 618,792 (She. 8, 1928). (8) Wdton, G . P., and Gardiner, R. P., U. 8. Patent 1,858;2:10
.
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(Xsy IO, 11132). Rr;ir:iu~u hoiii l a , 1833. Preseoted before lie Diviiiun of Agricultursi end Food Ciiemictry a t the 85th Meeting of tlie lmeiioan Chemiosl Society, Wseiiinpion, D. C.. Maroh 26 to 31, 1933.
Electrically Heated Steam Generators for the Process Industries S. %. O w h*, Westinghouse Electric and Manufactitring ASY of tlJe prroeess indnsbries generate their own electric energy, utilizing bled or exhaust steam for process Iiertting. The problem of balancing tire electric load and the steam load is a difficult one and often leads to ti waste of fuel. AI, electric stearn boiler located a t the point of use of stearn heat can be of material assistance in obtaining t,hat balance so necessary to economical operat . i o n . Sucli an application also aroids the heat losses occasioned by long steam lincs to remote parts of the chemical plant. Still other p r o c e s s indiiitrirs using purchased electrical energ!: have a boiler plant for the winterofice heating load and for tire yearly process heating. Wliere the J m J C ess heating requirement8 arc small, it is often econoniical to produce steam electrically during the warm weather so that the power boiler may Re shut down. Thus the expensive o p e r a t i o n of tire power hniler is eliminated when the major portion of its capacity is not required. Although the cost of electrical energy m a y be h i g h e r t h a n tlie
Company, hlansfield, Ohio
cost of energy obtained by using gas, oil, or coal, this difference is usually overcome by savings 011 insurance, floor space, maintenance, working conditions, and labor savings. The number of rejects are also greatly reduced in many cases by using steam at the correct temperature required. The electric boiler may also be used in winter to take peak loads t,liat might exceed tlie capacity of the existing equipment. Where small amounts t ~ fprocess steam are required a t given pressures or temperaturcs, it is often economical to produce steani electrically. An illustration of this is mliere higher temperatures are required than can be obtained with the power house steam. Supposing the power liouse steam can be d e l i v e r e d where needed at 125 pounds gage p r e s s u r e (350’ P.) but for the given process a steam temperature of 375O F. is required. An electrically heated steam generator of a suitable size, generating steam at, 185 ponnds gage pressure (375” P.1. .. can he used to advantage. The only energy loss in the electric boiler, barring small electrical line losses, is the radiation loss of
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