THE
488
J O I J R N A I ~OF
and domestic uses, furnaces and appliances have been designed and constructcd best adapted to the use of gas, many having a sustained efficiency of eighty-five to ninety per cent, while all strani boilers are constructed with a view to the use OS coal as fuel. In the use of gas, irom seventy to seventy-five pcr cent cfficiency is about the maximum sustained. I n the tests madc at the Wcst Virginia University under the direction of Proi. C. R. Jones, very pi-:~ctical results were obtained, showing what can he done in continuous work. By making al1ow:rnre for in heat value of gas t.o be uscd, the cost OS readily be obtained. !$To compare with coal costs, allowance should he &de lor the Sollowing items, in addition to coal on track: cost of handling to grate bar, ash removal, rcpairs, grate bars, linings, tube cleaning (return tubular), and additional oil, boiler repair, overamount when gas fired, cleaning machinery (resulting from coal and ash dust), value of overload (short or long) possible with gas, value of automatic regulation and constantly uniform steam pressure under all loads all this must he determined and added to cost oi coal or dFducted from cost of gas before one can fairly nnd accurately compare relative costs. A detailed consideration OS this subject would rcquire the description of as many various applications as there are plants, as no two can he installed the same in all details, location oi plant with rcference to physical surroundings, conditions of fire room. stack draft, nature and type oi boilers, setting, constant or variable load, the type of man who superintends the steam plant-all must he considered in making s: success of the use of gas. ~
PIrTSBURO,
Pn.
GINEERING CHEMISTRY
INIIUS~RIAL
~~~~~
A VITRIFIED CLAY COMBUSTION TUBE WITH TAPERED
OUTLET OF STEELS, THE FERRO ALLOYS AND GRAPHITE u s C H I X L s s h l O R R l S JO,,hSon,
IN
Received May IS, 1913
The widespread use of the vitrified clay comtrustion boat introduced by the writer in '909 ("Analysis oi
Special Steels, Steel-making Alloys and Graphite." 1 n n Wile7 8r Sons, rqag) suggested t o the writw the possibility oi making an inexpensive combustion tube of similar material.
Vol. 5 . No. 6
After considerable experimenting a tube has been produced which has brcn in service night and day for several weeks and a t this writing is still running, giving perfect results. It has been the objcct of the author to producc n tube t h a t will not he so readily slagged with basic material which is thc extremely weak feature of the now almost universally used silica tube. The latter is of course entirely acid in its nature. Thc amount of experimenting that can be done along this linc be very considerable and much time must np sarily elapse beSol-e the most pcricct composition can be reached, hence the writer wishes to establish priority at this stage of the work. The good service already obtained by the author with the tapered clay tube (shown in the illustration), which is of simple and most inexpcnsive composition, inspires confidence that thi: days of the costly combustion tube Sor iron and steel works carbon determinations are numbered. The taper design for clay ware combustion tubes is original with the author and it has the atlvantage of reducing the rubber stopper nuisancc fifty per cent. The combustion train is also shown as it is now connected, and filled. J is the wcighing apparatus. The oxygen enters the sairty jar C containing liquid KOH, then passes throng11 the soda lime in E. next i t travels u p through D which contains anhydrous calcium chloride; it then crosses over and down through stick KOH contained in the jar in the rear and from thence into the little valve tube attached t o the rubber stopper. This mercury valve servcs a double purpose of absorhing sulfur coming from the rubber tubing and prcvents any possibility of CO, being forced in the wrong direction. rrhe entire train and furnace with the exception of the tapered clay tube, is essentially the same as when first published in May, 190s (/. A M . Chew. Soc.. 30. 773. The writer desires to acknowledge the assistance of Xr. Bayard Guthrie. of Park Works, Crucible
Factory, in preparing the apparatus necessary to work thc clay into shape. 'T,,S
,.*B"II*T"RY
CKUFIIILG
0,-rrt,:
STWL Cu.
l'AKK
W""KS
01 AMBKITA
P l m a u s o . P*.
