Tho gas leaving the retorts pasied thmuglr :m %in. acidproof iron pipe, insulated against hcat loss by a c,ovi:ring of asbestos, into the blench pot. The Iatt,cr \vas a mi:ill :icidproof iron pot packed with spiral acid-proof )lottery rings. In this bleach pot, a small amount of nitric acid was condtmsed and run off a.t,the bottom through a 3-in. line. The remainder of the fume passcd upward t,lirough the ring packing and into t.hc condensers proper. I3:ach eondenser eoiisisted of nine +in. acid-proof iron pipes comprising nine lengtlis of pipe 5 ft. long. connected at, the ends by return bend fittings so as to form a continuous vertical coil 6 ft. wide and 8 ft. high. These w r e spraqrd by cooling water on the outside for condensation of the Same t,o nitric acid. The pipes comprising the cimdeiiier were inclined in such a way that all acid condonscd ran off throueh the bleach not. where the ariion of
..
.
Towrer IS eiraped to tlie a,tmosphere practically free of nitric a,cid. Thc acid from tlie condensers and bleach pots Aoned through acid coolers, which consisted of loops of 2-in. acidproof iron pipe iinmerscd in a trough of water, and from t,he coolers passed directly into the mising tanks. Each unit was provided with three mixing tanks, of steel plnt,e construction, 8 it. in inside diameter, 30 Et. long, and with 8 2-in. lining of acid-proof radial brick. These t,:mks vcre so connected that each could draw oleum irom the oleum tank, weak nitric acid froin t,heweak acid tanks, or st,rong acid direct, from the strong acid lines. In mixing, tlie proper amount of oleum from tlie oleum st,orage tank was led into the mixing tank and followed by weak or st,ronn nitric acid in the mouortions necessarv to nive
ing in color of the product. The remainder of bhe gas, consisting of residual air in the retort. and all loivcr oxides of nitroed from the condenser through tile lines into liyponiri. The latter, of which t.hcrc were eight.cen t,o each unit arranged in t v o parallel lines of nine t o m r s each, consisted of 30-in. chemical stoneware sect,ions resting in acidproof iron dishes (Fig. 1). Thcrc were six tower sections to e:di to packed rrith spiral chemical rings. The flow of gas yias in swics ihrough these t,owers. Wat,er was start,ed from the top of T o m r 18 and \ixs pumped over each tower in turn in series, cvnntcrcurrcnt to t,he now girs. In this countercurrent circulation the vater gradually adsorbed tlie acid cominq off a t Towr 1 :LS\veal; nitric ticid. The
atid there was also provided a circulating piimp which drrw t,he acid from t,hr tank through a cooler and returned it to t,hc same tank. This acid cooler consisted of a coil of five lcnaths of 6-in. acid-re ing iron pipe sprayed with water. During the period peration there mas an average of 7200 lbs. of nitlatc per retort charge. It was found that, after thc difficulties always incident to t,he starting of a new plant, w r e overcome, it ivas possible to get about two and one-hult charges per retort per 24-hr. day, and, had the p h t continued t,o run on this schedule, could doubtless have been kept up with such retorts as m x e in operation. Inoluding the starting-up period, the yield of nitric acid per 100 Ihs. of ioiliimi nitratc xits app atcly 05 Ihs. The sulSiiric arid riltio to sodiinii niti.;itc 'I girtlylcss than 1 : 1.
Short Method for the. Ultimate Analysis of Coali
in :my apparatus suit,tLble for neciir:itely mc:iairing the carbon dioxide as shown in Fig. 3 . Having now the values in hand for sitlfur nnd 13. t. u,, the caleulstions are of a simple urdcr.
By S. W. Parr
U L I I M A T B AN*I.YSIS OP CO.>L 1JNI"LXEII.Y
0s ILLINOIS, URariX.4,
l,.L,N"Z6
011 ~irrrposcs of the engineer in boiler testing, the
F
Edlowing method for det,ermining the carbon, hydrogen, :md osygcn in coals has been in practical use for a niimher of yic:irs \yitli very sa.t,isfurtoryresults. 31,450 Wcight of rvailable bydrosen. 8. hi
Nitrogen prcsnni may be assii~ned
a courtant o i 1.26 per cent.
-
+
6 . Then, by difference, 100 (s C -i- H -i.N ash as weighed) = (0 -t IO.* 7 . 819 (0 -t 11) 'rotat Y. 1/9 (0 11) Combined hydro-
+ +
i
grii. (1.
An ordinary combustion of the coal is made with sodium peroxide by nee of the calorimetric bomb or similar devices, esp~eiallyadaptod t o total carbon or sulfur determination, as shonn in Figs. 1 or 2. The carbonate formed is discharged Presented hefoe the Division of Industrial and Engincering Chcmintrg the 03rd Meeting of the American Chcmieal Society, Birmingham,Ala., April 3 to 7, 1922. L
+
Then, combined hydrogen .wail4) = Total h y d r o p i
able hydrogen (8
+
By deriving the factors a5 thus indicated, we have all of the constituents as obtained hv ultimste I'rc. 3 analysis and with a degree oi nccuracy entirely commensurate with that secured by the longer process.
+
9 The exprcsion (0 Hj refers to the total oxygen plun that amount of hydmgen "eesiary to combine with i t to form water. This hydrogen i s referred to as "mmbined hydrogen" t o dieeieatiate it from the "available hydroge.en."
