T H E JOURNAL OF INDUSTRIAL AND E N G I N E E R I N G CHEMISTRY
V
ol. I. JA N U A R Y , 1909. No. 1.
T h e Jo u r n a l o f 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 P U B L IS H E D B Y
T H E A M E R I C A N C H E M I C A L S O C I E T Y .
BOARD OF EDITORS.
E ditor:
W . D. R ichardson.
Associate Editors:
Geo. P. Adam son, W . K . A lsop, E . G . B ailey, G. E.
Barton, W in, Cam pbell, F . B. Carpenter, V irg il Cob- leu tz, F ran cis I. D upont, W . C. E b a u gh , W in. C . G eer, W . F. H illeb rand , W . D. H orne, H enry M . H ow e, L . P. K in n icu tt, A . E . L each , F . W . L o v ejo y , K a rl L au g- eu b eck , A. D . L ittle, P. C. M cllh in ey , E . B. JNIcCready, J. M erritt M atthew s, T. J. Parker. J. D. P eu n o ck, C lif
ford R ich ardson, Geo. C. Stone, F . W . Traphagen, F . H . Thorp, E rn st T w itch ell, R obt. W ah l, W in . H . W a l
ker, M. C. W h itaker, W . R . W h itn ey.
P u b lish ed m o n th ly . S u b scrip tion p rice to n o n -m e m b e rs o f the A m erica n C h em ica l S o cie ty $6.00 y e a rly .
C op y rig h t, 1908, fo r th e A m e r ica n C h em ical S ociety b y W . D . R ic h a rd so n , E ditor.
Vol. I. JANUARY, 1909. No. 1.
EDITORIALS.
THE INDUSTRIAL CHEMIST AND HIS JOURNAL.
Th e necessity for a journal published in the interests of the A m erican T echn ical Chem ist and Chem ical Engineer m ust be apparen t to all en
gaged in m anufacturing pursuits, m ore especially those h avin g to do w ith processes and problem s of a chem ical character.
Pub lications devoted to printin g the results of chem ical investigation and research are not lac k ing. In fact, if thej^ w ere few er and their m atter edited and condensed, their readers w ould be the gainers. W e are, however, fortu nate in h avin g them , and w e m ust accord all credit and honor to those engaged in their publication for th eir self- sacrificing" efforts in the interest of our beloved
science, since the w ork of necessity m ust be a labor of love, as the m on etary rewards are m eagre if not en tirely lackin g, or the publications are conducted a t a loss.
L e t it not be said of the T echn ical Chem ist th at he loves his science an y less than his brother, who devotes his tim e to research or teaching. T h e S o cie ty desires to enlist the cooperation of the In du strial Chem ist in this Journal. I t does not seek th e publication of confidential m atters, or the secret processes of any com pany or w orks, b u t it believes th a t a certain lib erality in publishing broader inform ation on subjects of m anufacturing interest w ill be beneficial. F o r exam ple, w itness the m onum ental w orks of Lunge. T hese pages w ill be open for the publication and discussion of topics, the reading of which w ill m aterially in
crease the reader’s know ledge of not alone th a t branch of chem istry in w hich he is w orking, b u t of its w hole industrial field, and he will obtain m any hints of value.
T o illustrate— observing the reaction takin g place in the m etallurgy of lead, w herein its sulphide reacts on its sulphate w hen heated, producing m etallic lead and sulphurous anhydride, a like re
action w as suggested in the case of sim ilar barium com pounds, hence an ingenious and cheap process for barium h ydroxide w as devised and patented.
B y ap p lyin g a m odification of J. L aw rence S m ith ’s m ethod for the determ ination of alkalis in sili
cates, using calcium chloride and lim estone, a good m ethod w as devised in the lab orato ry of a w orks th e w riter w as connected w ith, fo r the extraction of potash salts from feldspar. Should our supplies of these salts from G erm any be curtailed, or stopped, b y reason of w ar or tariff conditions, the process w ould be econom ically practicable. T h is was hinted a t in a paper read b y Cushm an before the N ew Y o r k Section last w inter.
W e still seek a practical process fo r the u tiliza
tion of the chlorine in the am m onia soda process, although T u ck er has shown how the alkaline chlor
ates can be m anufactured from calcium chloride b y electrolysis and double decom position.
T h e recovery of zinc associated w ith p v rite has been and is engaging the atten tion of the chem ist, and
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it looks as though it w ould be solved b y an elec
trical process. Fusel oil is scarce and high. I f the proper ferm ent or yeast can be propagated, am ylic alcohol could be m anufactured ch eap ly and profitably.
W e could continue on in th is suggestive w ay, b u t enough has been w ritten to show the value of p u ttin g before our readers subjects which not alone m ay interest them b u t the entire chem ical world.
T h e chem ical engineer is called on in our indus
tr y to ad ap t the m aterial best suited to the pro
cess in hand. In the lab orato ry this m ay be glass, porcelain, platinum , or w h at-n ot; b u t from their expense or fragile character, these are n o t usually perm issable in large scale operations. H e has, therefore, to use the construction m aterial a t com
mand, as sa y iron, lead, copper, alloys and brick.
T o do th is properly he m ust have, n o t alone the training of a chem ist b u t also th a t of an engineer, and should have a t hand th e m ost recent develop
m ents of the science which pertain to the installa
tion or im provem ent of existing processes.
W e often hear of the success of a lab oratory m ethod, and its failure w hen applied on a manu
factu rin g scale. In m any cases failure is due to lac k of engineering know ledge, or of n atural laws governing the changed conditions. W e read in the la s t report of A dm iral N. E . Mason, Chief of Bureau of Ordinance, U . S. N a v y , th a t experim ents in drying nitrocellulose b y m eans of alcohol m et with success in the lab oratory, b u t w ere unsuccessful on a w orking scale, for reasons th a t to him re
m ain obscure. W e w ould like to know the reason w h y ; probably the chem ical engineer can tell us.
T . J . Pa r k e r.
THE ETHICS OF ENGINEERING SUPPLIES Th e crusade, which during the la st few years has been carried on in the m agazines against the so-called p a te n t m edicines and other articles of this nature, has produced a great and lastin g good.
T h e agitation which culm inated in the national F ood and D rugs A c t of 1907 also has served to aw aken the public to the m an y deceptions which are being practiced and the m any worthless prepara
tions for general dom estic use w hich are on the m arket. T h e result of th is m ovem ent has been first to force a great m an y of the more palpable frauds to be w ithdraw n from the m arket, and second to provide for the correct lab elin g of all
others, so th a t th e purchasers m ay be in position to b u y intelligently.
O n ly those m aterials, how ever, w hich m ay be classified under th e head of food and drugs fo r th e hum an system com e w ithin th e scope of th is legis
lation . A steam pow er p lan t considered as an organism has also afflictions for th e cure of w hich m an y so-called p a te n t or secret m edicines are offered fo r sale. T h e average engineer is. no more in position to ju d ge of these preparations th an ¿is the housew ife able to distinguish betw een a v a lu a ble or a w orthless prop rietary m edicine. Such im position is found in m an y of the w ater softeners and boiler com pounds w hich are offered fo r sale as panaceas for all the ills to w hich th e steam boiler is subject. N o t infrequ en tly th e va lu e of such m aterials varies in versely as their cost. O ur a t
tention has recen tly been called to a certain w id ely advertised “ a llo y ” guaran teed to p reven t th e cor
rosion or p ittin g of boilers, and w hich w as sold a t an e xo rb itan t price. I t proved to be ord inary feathered zinc. M any boiler com pounds are m ix tures of soda ash, and alm ost a n y u su ally w o rth less filling m aterial th a t m ay be a t hand w hen the m aterial was p u t together.
A cam paign of education m igh t w ell be under
taken w hich w ould serve to place before th e con
sum ing public the danger in prom iscuously b u y ing, and ign oran tly using, a n y m ixtu re w hich a sm ooth-tongued salesm an m ay see fit to offer. I t m ay be argued th a t since w e h ave in our com m un ity a large num ber of skilled com m ercial analysts, there is no adeq uate excuse fo r prom iscuous b u y ing, b u t th is does n ot en tirely relieve th e situ a
tion. So long as goods intended for the engineer
ing public are m ade and vended b y salesm an and circular w ith ou t restraint or control th e y w ill be sold, even though im properly lab eled or a ctu a lly fraudulent. T h e lis t of products used b y engi
neers and peculiarly susceptible to adm ixtu re is large: pigm ents, oils, varnishes, solvents, boiler com pounds, lub ricatin g oils, m etals and allo ys are a few' of them . T h e list of products cap ab le of being sold b y m eans of unw arranted statem en ts in regard to useful qualities or properties is also large. T h e chem ical fak e assum es m an y guises.
T h e consideration of general w a y s and means, educational and legislative, for elim inating it is w o rth y the consideration of all chem ists interested in the upbuilding of the profession and exten d in g its usefulness.
Wi l l i a m H . Wa l k e r.
T H E J O U R N A L O F 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 . 3
THE SUGAR INDUSTRY IN ITS RELATIONS TO THE UNITED STATES.
Th e per ca p ita consum ption of sugar in the U nited S ta te s was 7 7 .5 4 lbs. in 1907, w hich e x ceeds th a t of a n y previous year.
1907. 1906.
T h e tota l con sum ption was, in lon g t o n s ... 2 ,9 9 3 .,9 7 9 2 ,8 6 4 ,0 1 3 con sisting o f D om estic cane (La. & T e x a s ) .. . 2 6 4 ,9 6 8 267 ,94 7
D om estic b e e t 3 7 5 ,4 1 0 3 00 ,31 7
M a p le 1 0 ,0 0 0 6 ,0 0 0
Molasses s u ga r 6 ,2 4 9 8 ,1 5 0
T ota l d o m e stic 6 5 6 ,6 2 7 5 82 ,41 4
H aw aii 4 1 8 ,1 0 2 3 43 ,85 7
P orto R ic o all . . 2 12 ,85 3 193,978
Philippine Islands cane . . 10,7 00 4 1 ,9 0 0
C uba 1 ,3 4 0 ,4 0 0 1 ,1 6 5 ,9 9 4
T o ta l receivin g tariff con cession . 1 ,9 8 2 ,0 5 5 1 ,7 4 5 ,7 2 9
Foreign raw ca n e 3 4 7 ,5 0 9 3 57 ,05 7
Foreign raw b e e t 6 ,7 8 0 175,827
Foreign refined b e e t . 949 2 ,7 3 4
F oreign refined c a n e . 59 252
T o ta l F oreign p a yin g full d u t y , 3 5 5 ,2 9 7 5 3 5 ,8 7 0
T h e refining of this sugar w as accom plished as fo llo w s:
B y sugar refineries 2 ,4 6 5 ,8 8 8 1 ,4 4 0 ,3 3 4 B y b eet sugar fa cto rie s 3 7 5 ,3 5 8 3 0 0 ,0 5 9
B y H awaiian ca n e 1 ,6 7 4 1 6,964
B y Foreign refineries 1 ,0 0 8 2 ,9 8 6
T ota l am ou nt refined su g a r 2 ,8 4 3 ,9 2 8 2 ,7 6 0 ,3 4 3
F rom the above, it m ay easily be seen th a t this co u n try is one of th e largest sugar consum ers of th e w orld, b u t th a t although our dom estic beet sugar in d u stry is advan cin g (m ainly in the W est) w e are still in no position to com pete w ith the raw cane sugar production of m ore tropical countries.
In the countries producing this raw sugar, the processes of m an ufacture h ave received close scientific stu d y, resulting, in a high developm ent of technique. A generation ago b ee t sugar m anu
fa ctu re advan ced m ore rap id ly th an cane, b u t the la s t few years h ave brou gh t cane sugar m anufac
ture also up to a high degree of efficiency and econom y. N o t only h ave some new varieties of cane of superior ch aracter been developed, b u t b e tte r m odes of c u ltiv atio n h a ve been w orked out. G rea tly increased yield s of sugar from the cane h ave been obtained through increasing the e xtraction of juice from cane b y em ploying pre
lim inary crusher or shredder and pressing three or even four tim es instead of only tw ice as form erly in three-roller m ills. M aceratin g w ith abu n d an t w a ter aids in th is added extraction , w hich now rises to 90 or 95 per cent, of the sugar in the cane as contrasted w ith 75 or 80 form erly obtained.
Som e factories em ploy as m uch as 30 or even 40
per cent, of the w eigh t of the cane iii w ater of m aceration, ap p lyin g it in m ultiple, instead of all a t one place. E v e ry 4 per cent, of w ater is thus found to increase b y ab out 1 per cent, the e x tra c
tion of sugar in cane. B e tte r means of defecation h ave been developed, as in the pre-heating and super-heating devices of D em ing. H a tto n ’s new continuous defecation system prom ises consider
able advan tage, and m ay elim inate a great part of the filter press w ork. M ultiple effect evap ora
tors h ave reached a high efficiency, the quadruple effect being in com m on use. In the L illie app ara
tus a reversal of both juice and steam Is possible, g re a tly dim inishing th e am ount of incrustation.
K estn er has developed a ve rtica l design containing tub es 25 or 30 fe e t long, for evap orating solutions which tend to foam , and these have been found ve ry good for alkaline vinasse, especially as the parts can all be m ade of iron, keep in g down the co st of construction. M uch more thorough cry stalliza tion of sugar from m agm as is now effected b y keeping the m agm as in gentle m otion and lub rica
tin g th e stiffening mass b y occasional injections of exhausted molasses.
In raw beet sugar m an ufacture, as in cane sugar m aking, the recent advan ces have been m ade in im proving the efficiency of a host of operations, rather th an in developing a n y rad ically new basic principles. R ecen t years h ave seen a considerable reduction in the am ount of lim e used in defecating the raw ju ice and a satisfacto ry developm ent of the Steffens process of precip itating the sucrose as a lim e saccharate from the residual molasses.
A p re tty .satisfactory o u tlet for the b eet pulp has been found in th e form of c a ttle food, m ade either b y d ryin g in specially designed kilns, or b y m oisten
ing w ith w aste molasses and feeding direct. F orm aldehyde has com e to p lay an im portan t p art in preserving sugar solutions th a t have to be held over during shut-downs, in lieu of lim e.
T h e refining in d u stry has already been so highly developed th a t g re a t innovations in the technique are rare. T h eoretical advan ce has been constant and m an y im provem ents appear in m atters of de
tail. T h e system of crystallizatio n in m otion for low prod u cts has been adapted from the raw sugar in d u stry w hile the use of ultram arin e and sulphur dioxide has been largely discontinued, due to the operation of the pure food law .
T h ere are several points in the process of sugar m an u factu re and refining w here g reat im prove
m ent m igh t be afforded and w hich should a ttra c t
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th e attention of investigators. A great advance w ould arise from a suitable electric process which could dissociate and rem ove the organic im purities as well as the salts from low -grade sugar solutions.
A cheap substitute for bone-black, of equal effi
ciency and d u rab ility should prove a boon. Some good m ethod of continuous m echanical filtration of sugar solutions w ould be of considerable value, and the same is true of a continuous system of purging the sugar grains from their enclosing m other-liquor a fter boiling. W . D. Ho r n e.
THE FIXATION OF NITROGEN.
Ha r d l y any achievem ent in Industrial Chem
istry has attracted such wide-spread interest as h ave the processes w hich render it possible to make use of the nitrogen of the atm osphere in a com m ercial w ay. W hen P riestley first dem onstrated th a t atm ospheric nitrogen could be converted into nitric acid under the influence of the elec
tric spark, he little dream ed th a t his discovery w ould some d a y form the foundation of a large and profitable industry. W e m ay be a little h asty in anticipating this last assertion, b u t the progress w hich has already been m ade is alm ost .an assurance of future success. T h e great achieve
m ents in electrotechnics h ave m ade it possible to produce electric energy in large q u a n tity and, in turn, m ake it availab le for converting the nitro
gen of the atm osphere into valuable compounds.
I t has been know n for som e tim e th a t nitrogen and hydrogen can be united b y an electric dis
charge, or under favorab le conditions, b y contact w ith certain substances. T hese fa cts have been utilized b y m any inventors, b u t thus far, none o f the inventions along these lines have proved of much practical value. T h e progress, however, which has been m ade in other directions during the last few years in fixing atm ospheric nitrogen has been rem arkable, and has for the time, over
shadowed other achievem ents in Industrial Chem istry.
T h e process of F ran k & Caro in w hich the nitro
gen of the air is separated and com bined under certain conditions w ith calcium carbide to form calcium cyanam ide is giving ve ry prom ising results.
T h e developm ents of the applications of the initial trials of this process have justified the erection of several factories in w id ely separated localities to test its p racticab ility on an extensive com m ercial basis.
T h e principle in v olvin g th e d irect conversion of the nitrogen of the atm osphere to n itric oxide and n itric acid b y aid of the electric sp ark is no longer confined to the class-room dem onstrations.
T h e experim ents of Crookes, L ord R a yleig h , Lepel and others form ed the foundation fo r the indus
trial ap plication of the earlier discoveries. W hile the first industrial ap plication of this principle b y th e A tm ospheric P rod ucts C om pan y under the p aten ts of B rad ley & L o v e jo y a t N iagara F a lls did n o t prove successful, it stim ulated fu rth er research along this line, and la te r developm ents g ive m uch more prom ising results. In th is first attem p t, it w as clearly dem onstrated th a t n itric acid could be produced on a large scale, and it on ly remained to cheapen th e cost of production.
T h is w as accom plished in a large m easure b y the process of B erkeland & E y d e w hich tvas sim ilar in th e main to th a t of A m erican inven tors excep t th a t th e efficiency of the ord inary electric arc is g re a tly increased b y flashing in a m agn etic field a t a v e ry high tem perature. In stead of a m u lti
tud e of th in streaks of electric ligh t, this process provides for a large disc of flam e w hich affects a large volum e of air so th a t the oxid atio n of n itro
gen is m uch m ore rapid and is accom plished w ith m uch less expen ditu re of energy. T h e exp eri
m ental fa cto ry for testin g this principle, erected near N ottoden , N orw ay, h avin g the a d van tage of ve ry cheap w ater power, has given such encourag
ing results th a t th e production w ill be attem p ted on a larger scale. T h u s w e h ave a t the present tim e, tw o processes for the u tilizatio n of atm os
pheric nitrogen operated under en tirely different chem ical principles, both of w hich g iv e g reat prom ise of ultim ate success. Im provem en ts are con
sta n tly being m ade w hich increase th e efficiency, and lessen the cost of production, and w e can rest assured th a t long before w e h ave a nitrogen fam ine our w ants will be supplied.
T h e im portance of these invention s and their successful applications can h ard ly be overestim ated.
T h e dem ands for nitrogenous com pounds, both for industrial and agricultural purposes, are rap id ly in creasing year b y year, w hile th e a vailab le supplies are rap id ly decreasing; it is estim ated th a t the consum ption of nitrate of soda alone am ounts to over 1,700,000 tons per annum , and a t this rate it is predicted th a t the deposits w ill be e x hausted in less than fifty years.
W hile the free nitrogen form s four-fifths b y volum e of the atm osphere, it is n ot probable th a t the
T H E J O U R N A L O F 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 . 5
com bined form s one m illionth part. Considering, therefore, th is inexh au stible supply, and con
sidering w h a t it m eans to agriculture and the arts if it can be utilized, the solution of the problem of conserving the nitrogen of the air in a com m ercial w ay, w ill be recorded as one of the im p ortan t in
ventions of m odern tim es.
F . B . Ca r p e n t e r.
STANDARD METHODS OF ANALYSIS.
We h ave seen w ith a good deal of interest, a brow n-covered p am ph let of th irty-tw o pages, p u b lished b y the U n ited S ta te s Steel Corporation in the interests of their chem ical force and entitled “ T h e M ethods of the U n ited S ta te s Steel Corporation for the Com m ercial Sam pling and A n alysis of Iron O res.”
T h e w o rk of developing the m ethods w as per
form ed b y a com m ittee consisting of: J. M. Cam p, Carnegie Steel C o.; W m . B rad y, Illinois Steel Co.;
W . B . N . H aw k, N ation al T u b e C o.; A . B . Clem- ence, A m erican Steel & W ire C o .; E- A . Separk, O liver Iron M ining C o.; G. D . Cham berlain, Car
negie Steel Co.
T h e preface explain s the purpose of the Steel C orporation and the chem ists in form u lating these m ethods. “ T h e Chem ists’ Com m ittee w as ap pointed for the purpose of u n ifyin g the m ethods of sam pling and an alysis of the m aterials consumed and produced b y the U nited S ta te s Steel Corpo
ration, w ith th e purpose of rendering more accu
rate the a n a ly tical results obtained. O w ing to the difference in education or practical train ing of the chem ists in charge of th e lab oratories of the Steel Corporation, wherein iron ore is analyzed, a w ide divergence in th e m ethods of an alysis w ould be exp ected ; b y harm onizing these m ethods, the errors in cid en t thereto w ould be m inim ized.”
W e understand th e w'ork of the com m ittee w ill be continued and the m ethods for th e analysis of other m aterials developed.
C ontrasted w ith tw e n ty or tw en ty-five years ago, the condition of an a ly tical ch em istry a t the present tim e in th is country, and indeed th rou gh o u t the w orld, is such th a t we m ay fa ce the fu tu re hopefully. M any organizations have contributed to th e unification of the m ethods w hich are in con
sta n t use to-d ay. W e need on ly recall th e w ork of the variou s com m ittees of the A ssociation of Official A gricu ltu ral Chem ists on fertilizer, food and fa t analysis, of th e Com m ittee on U n ifo rm ity
of the A m erican Chem ical S o cie ty under the able leadership of Dr. H illebrand, and m ore recently of the Com m ittees of the Society for T estin g M ate
rials to realize how' great has been th e advan ce from the ch aotic condition in which th e unorgan
ized m ethods of analysis existed a few years ago to the fa irly w ell organized condition in which w e find them to-day.
M uch w ork rem ains to be done. A m on g the contrib utin g organizations which are endeavoring to place com m ercial a n a lytical m ethods on the high plane where th ey belong, w h a t one could be more useful than the large corporation which em ploys num bers of chem ists and operates • m any chem ical ■ laboratories in various localities and, in fa ct, which finds the d aily routine application of a n a ly tical m ethods a guide and a necessity for the control of all its m anufacturing operations?
T h e pessim ist w ill say th a t already w e have too m any and too various organizations w orkin g on the uniform ity of chem ical m ethods, and the addi
tion of even one m ore to the ranks is h ard ly ad
vantageous. W e feel m ore confident in the m atter and b elieve th a t for present needs, the various organizations w hich h ave been and are w orking o u t the details of m ethods, are w orkin g along the righ t lines. F or the future, when th ey shall have accom plished th eir w ork, the represen tative organ
ization of chem ists in this and in other countries m ust see to it th at all the m ethods of analysis are w orked into one com prehensive system , which shall n o t be fixed for all the tim e, b u t shall be k e p t alive b y a ctiv e com m ittees and continuous additions and im provem en ts as the science develops.
W . D . Ri c h a r d s o n.
O RIG INAL ARTICLES.
FREE LIME IN PORTLAND CEMENT.
B y Al f r e dH . Wh i t e. R e ce iv e d O ctob er 3. 1908.
T h is paper describes a sim ple m icroscopic test fo r free lim e in P ortlan d cem ent and discusses the result of its ap plication to a num ber of com m ercial cem ents and to others m ade in the lab oratory.
T h e usual an alysis of P ortlan d cem ent shows lim e to form over s ix ty per cent, of the w eigh t of the clinker, b u t does n o t g ive an y clue to the form in w hich this lim e exists. I t is rather generally, alth ough b y no m eans un iversally, assum ed th a t
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th e lim e m ust be in a state of com bination, b u t the evidence for this belief is alm ost en tirely indirect, because of the difficulty of determ ining directly w hether the lim e in cem ent is free or combined.
T h e application of aqueous solutions of any sort is im practicable because of the rapid decomposition of norm al cem ent b y w ater w ith resultan t form ation of calcium hydroxide. A nh yd rou s solvents for lim e have been proposed, n o tab ly glycerine and a solution of o xalic acid in absolute alcohol, b u t the m ethods are a t b est tedious, and if free lime is detected there is alw ays the suspicion th a t it m ay h ave been due to the action of m oisture in the hygroscopic reagents, rather th an to actual free lim e in the cem ent. N either can the m ethod be applied w ith certain ty to com m ercial cem ents which h ave been exposed to the air and m ay be p artially hydrated. A solution of phenolphthalein in a non- hygroscopic solvent, preferably benzol or chloro
form , has been proposed b y R ic h te r1 fo r the q u alita
tiv e detection of lim e, b u t its use is also restricted to perfectly fresh clinker w hich has n o t been ex
posed to m oist air.
T h e B ecke method for determ ining free lim e from its high index of refraction as used b y W righ t2 in his exam ination o f the lim e-silica series of minerals prepared b y D a y and Shepherd perm its calcium oxide to be detected w ith certain ty even in the presence of its hydroxide, b u t the m ethod is not on ly tedious b u t extrem ely try in g to the eyes, for it is necessary to focus on and exam ine individ
ually each grain on the slide w ith a high power o b jective and feeble illum ination.
P R O P O SE D T E S T F O R F R E E L IM E .
T h e m ethod here proposed for the detection of free lim e is based on the form ation on the slide of the m icroscope of a characteristic crystallin e calcium phenolate readily recognizable in polarized light.
T h e reagent is prepared b y dissolving crystallized phenol in an im m iscible and rather non-volatile solven t and adding a trace of w ater. T h e m ethod of preparation preferred b y the author is to dissolve 5 g. of phenol in 5 cc. nitrobenzol and add to this solution tw o drops of w ater. Instead of nitro
benzol, alpha brom -naphthalene’ m ay be used, and is for some reasons, n o tab ly its low er vo latility , to be preferred. I t does not, however, g ive such sharp results as nitrobenzol. X y lo l gives good results as a solvent, b u t is too volatile and evaporates too q u ick ly from th e slide. T h e am ount of w ater
1 Thonindustrie Z eii., 1903, 1S63.
1 A tn er. Jour, o f Science, 172, 266 (1906).
in the reagent m ay v a r y som ew hat from the am ount given. A n anh ydrous solution reacts v e ry slow ly.
T oo m uch m oisture p revents the form ation of good crystals and m ay also decom pose the norm al cem ent.
T h e solution m ay also be m ade to g ive a color reaction b y dissolving o .io g. phenolphthalein in the ab o ve solution, b u t the presence of phenol
phthalein hinders, and m ay som etim es prevent, the form ation of definite cry stals so th a t it is recom m ended to use a separate solution for th e color test w hen th a t is desired.
In m aking this test ab o u t tw o or three m illigram s of the fin ely powdered m aterial are placed in the center of a m icroscope slide, a drop of reagen t p u t upon it and then a cover glass, w hich is pressed dow n and rubbed gen tly to and fro till the cem ent spreads itself out som ew hat. I t is ad visab le n o t to spread the cem ent ou t too th in ly b u t to le av e a th ic k nucleus where the cry stals w ill first appear, and to have the thickness decrease tow ard the edges. B y this arrangem ent it is easier to g et a rough approxim ation of the am ount of lim e present.
T h e slide is now observed in a p olarizing m icro
scope w ith the nicols crossed, or if easier for th e eye, w ith the polarizer rotated sligh tly. T h e author usu ally uses a tw o-thirds inch o b je ctiv e and one inch eyepiece giv in g a m agnification of a b o u t 80.
T h e phenom ena appearing w hen pure lim e alone is being observed w ill first be described. W hen th e freshly-prepared slide is p u t on the m icroscope th e lim e being isotropic is alm ost in visible and the whole field is dark. W ith in a few m inutes the edges of th e-fragm en ts of lim e begin to show b ril
lia n t points which in a quarter of an hour develop
Fig. 1.
T H E J O U R N A L O F 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 . 7
in to b rillian t clusters of radiating needles as shown in F ig. i w hich is a photom icrograph of a com m ercial cem ent. O n accoun t of the g reat contrast in illum ination betw een the b rillian tly refracting calcium phenolate and the feeb ly refracting cem ent th e photom icrograph shows nothing b u t the calcium phenolate cry stals and does n o t show these sharply since their strong double refraction m akes them appear to be surrounded b y a halo. T h e eye of th e observer a t the m icroscope can readily discern the individual crystals form ing w h a t are only blotches of w h ite in the photograph. I f the lim e fragm ents are crow ded too closely togeth er on the slide th e crystals interlace so th a t their structure can n ot be noted. T h ese crystals grow till in the course of a couple of hours th ey m ay be o. i mm.
long. V e r y little fu rth er change is noticeable for six hours, b u t in tw en ty-fo u r hours the nitro
benzol w ill h ave largely evap orated and the crystals m ay h ave en tirely disappeared. Confusion from form ation of crystals of phenol has never been observed b y us, the m oisture present in the reagen t or absorbed from the air p rob ab ly p reven tin g the phenol from crystallizin g w hen the solvent evaporates.
H yd rated calcium oxide gives needles sim ilar to the oxide, b u t th ey gen erally form m ore rap id ly and are finer. On the other hand, th e crystals form ed from lim e w hich has been fused in the electric arc h ave a different form . In stead of straigh t needles th e cry stals appear as plum es or feath ery p etals w hich in favo rab le cases g iv e the group som ew hat the appearance of a chrysanthem um . Som ething of th is appears in F ig. 2 w here the
Fig. 2.
dark nucleus in the upper group shows the granule of free lim e from w hich the plum e-like crystals grew.
N o substance other than calcium oxide or h y droxide has been found to g iv e this reaction. C al
cium carbon ate does n o t g iv e it. Burned dolom ite does, b u t not burned m agnesia, although it has been sy stem atically tested for each io o ° in terval from 600-1600° C. Fused ortho-silicate of lime, 2 C a 0 .S i0 2, does n ot react w ith the reagent. A t tem p ts to m ake a tri-calcium silicate w hich w ould n ot show free lim e have, w ith one exception, been failures. I t is not the intention here to discuss the m uch-m ooted question of the existence of tri-calcium silicate in P ortlan d cem ent, b u t it is w ith in the scope of this paper to record th a t w e h ave found th a t fused tri-calcium silicate alw ays contains free lim e, as reported b y D a y , Shepherd and W right, and th a t tri-calcium silicate burned a t low er tem peratures usually contains free lime.
W e have, however, been able to prepare one sin
tered sam ple of th e 3 C a 0 .S i0 2 com position in w hich free lim e could n o t be detected b y a n y test, w hich w as hydraulic, and w hich stood a perfect boiling te st of tw en ty-fo ur hours. I t is our belief th a t this represents an unstable condition, the free lim e h avin g been brou gh t into solid solution, b u t final equilibrium n o t h avin g been reached.
T h e solution containing phenolphthalein turns red in the vicin ity of particles of lim e w ith in a few m inutes. U su ally crystals appear later. C al
cium hydroxid e also gives this reaction. Good P ortlan d cem ent does n o t show a n y pink spots for several hours, nor does the one good sam ple of 3 C a 0 .S i0 2 which w e have been able to prepare.
On the other hand, m agnesium oxide burned a t tem peratures of ab o u t io o o ° C. gives alm ost as viv id a red as lim e. W e do not regard th e indica
tion from th is solution as so valu ab le as those shown b y th e one w ith o u t phenolphthalein.
F R E E L IM E IN P O R T L A N D C E M E N T S.
W ith these experim ents as a basis, the w ork w as extended to P ortlan d cem ents. F o rtu n a te ly there w ere still on hand in the lab orato ry sealed sam ples of n early all the cem ents m ade b y P ro fessor C am p b ell1 in his studies of the constitution of P ortlan d cem ent. W ith this abu nd an t m aterial a t hand, it w as a re la tive ly brief m atter to deter
mine th a t free lim e w as a lw ays present in under
burned cem ents, and th a t as the tem perature of burning w as increased, the free lim e disappeared
1 Jour. A m . Chcm. S oc., 24, 248, 969 ; 25, 1103; 26, 1142; 28, 1273.
8
as soon as a th orough ly clinkered and sound cem ent w as obtained. F ig. 3 is a photom icrograph of such an underburned cem ent show ing abundant
K g - 3-
free lime. T h is cem ent disintegrated on the boiling test. T h e same cem ent when burned a t a tem pera
ture 45° C. higher did not show any free lim e and passed the boiling test perfectly. In an experi
m ent a t the tim e in progress in th e lab oratory where an a tte m p t w as being m ade to b u m a ve ry basic cem ent a t the highest attain ab le tem perature, it w as possible to predict w ithin ten m inutes from the tim e the clinker cam e from th e kiln th a t the cem ent w ould be unsound as it still contained free lime— a prediction confirmed b y the boiling tests.
FR E E L IM E IN C O M M E R C IA L C E M E N T S.
T hese lab orato ry tests afforded direct evidence of the correctness of the usual belief th a t a good P ortland cem ent should not contain free lim e. A n exam ination of such normal com m ercial Portland cem ents as were a t hand added a negative confirm ation, as th ey did n o t show free lime. (N at
ural rock cem ent w hich is burned a t a low tem perature does contain free lim e.) A n in vestiga
tion w as then started to determ ine how far free lim e m ight be the exclusive factor causing un
soundness in com mercial cem ents, bu t as is fre
qu en tly the case in pathological w ork, much dif
ficu lty w as experienced in procuring specimens with a reliable history. L etters were sent to several of the large railroad and testing laboratories ask
ing them to send the w riter small sam ples of such unsound cem ents as cam e into their laboratories.
I t speaks well for the care exercised in the cem ent
m ills th a t the usual rep ly to our letter w as a re
gret th a t th e y could n o t afford m uch assistance as v e ry little unsound cem ent cam e into their hands. H ow ever, enough sam ples w ere sent to m ake the results of interest. T h eir discussion should be prefaced b y the statem en t th a t the te st
ing lab oratories were requested to place one or tw o good cem ents w ith each lo t of poor ones and to m ark them all sim p ly w ith a serial num ber so th a t th ey should really be unknow n sam ples to the m icroscopist and th a t the m ethod m igh t re
ceive an im partial test. T h e results of the boiling te st w ere reported b y the testin g lab o rato ry after th ey had received the report of the m icroscopic exam ination. T h e M ichigan T echn ical L ab o ra to ry sent a t different tim es sixteen sam ples, and the best idea of the ap p licab ility of the m ethod m ay perhaps be gained b y sum m arizin g th e results as determ ined m icroscopically and as subsequen tly reported b y the testin g lab orato ry.
Co m p a r i s o n o f Mi c r o s c o p i c a n d Bo i l i n g Te s t s o n Co m m e r c i a l Ce m e n t s.
M icr o s co p ic rep ort.
C em en t N o.
T im e in m in u tes b efore
lim e crysta ls
a p p e a r e d . R em a rk s .
R e p o rt o f b o ilin g test b jr te stin g la b o r a to ry .
1339 A 10 D isintegrated
1339 B 69 S ou n d b u t w eak
1339 C 7 D isintegrated
1340 N one E v en after
s ix hours
O . K .
1340 B 30 R adial cracks
1340 C 40 “
1341 A 10 “
1341 B 35 “
1341 C 30 “
7352 6 Sm all am ou nt O. K .
7357 9 C onsiderable N o cracks, b u t pats
crum bled easily
7357 aerated 35 N o t m uch S ound b u t w eak
7359 20 Considerable Cracked and dis
integrated
7362 35 N o t m uch O. K .
7365 A 60 “ S lig h tly w eak
7365 B 30 “ W ea k and crum bled
easily
T h e agreem ent betw een the m icroscopic and the boiling tests is, on the whole, good. T h e m icroscopic tests d etected all of the bad cem ents and afforded some idea of their relative inferiority.
W here much free lim e w as e vid en t w ithin a h alf
hour the cem ent showed itself to be v e ry bad w hen boiled. W here a longer tim e w as required fo r free lime to show itself or w here only a rela
tiv e ly few isolated crystals w ere detected on the slide, the cem ent w as better, and graded up to one which passed the boiling test. O f the three cem ents m arked O. K . o n 'th e boiling test, the m icroscopic test passed one (1340) as perfect, b u t condem ned
T H E J O U R N A L O F 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 . 9
the other tw o. O f these tw o, No. 7362 w as reported as show ing a little free lim e in th irty-five m inutes.
Su bsequ en t m icroscopic tests on this cem ent have shown several slides where free lim e w as en tirely ab
sent, so th at it seems probable th at the am ount of free lim e in th is cem ent is so sm all as to be negligible.
T h e third cem ent m arked O. K . on the boiling te st showed free lim e v e ry q u ick ly, though in small am ounts, and subsequent tests h ave never failed to show it. T h e discrepancy here m ust remain unexplained from lack of evidence, although a possible explan ation m ight be found if it were know n w hether the cem ent had been aged a t the mill. T h e influence of aging w ill be discussed later.
A n oth er series of nine cem ents received from Dr. C. B . D u d ley, of the P en n sylvan ia R ailroad C o ., is of interest because of the to ta lly different nature of the report upon the m icroscopic exam in a
tion, an e x tra c t from which is as follow s: “ None of them are ve ry bad and I do not find the ch aracter
istic crystals of calcium phenolate in any of them.
H ow ever A , C, D , F and H show rather too pro
nounced a color w ith the reagent, and I should be suspicious of their soundness, although w ith m y present know ledge, I w ould not have ventured to condem n them as bad. Cem ents B , G and I seem perfectly good. Cem ent E is sligh tly sus
picious.” Dr. D u d le y ’s rep ly is as follow s: “ T h e list of cem ents w hich w e sent to you shows accord
ing to our record th a t A , B , C, D , E and F were w h a t we call ‘poor on boiling te st,’ w hile G , H and I were ‘good on boiling te st.’ Y o u r results seem to have picked ou t all the poor ones b u t one, and to have crossed in the case of one. I w ould like to say th a t these sam ples were n o t especially saved a t the tim e th e te st w as m ade b u t w ere taken from the records, so th a t there w as a lw ays the po ssib ility of sam ples being a little m ixed.”
A lth o u gh this agreem ent w as n o t altogether bad, it w as disappointing to us for it did n o t seem as if the cem ents in question had shown enough free lim e to cause unsoundness. B earin g in mind the possibility of aging h aving changed the cem ents, a boiling test w as m ade on sm all pats, w hich cam e loose from the glass on tw en ty-four hours’ steam ing b u t were otherw ise perfect. F u th er correspond
ence w ith Dr. D u d le y showed th a t there had been o p p ortu n ity for the cem ents to age since the boil
ing tests had been m ade in his lab oratory, so th at the net show ing for the m icroscopic te st is con
sidered a good one.
A n oth er lot of cem ents interesting from the standpoin t of effect of aging cam e in from the Osborne E ngineering Co. O ur report w as as follow s: “ Nos. 1, 2, and 3 decidedly bad, N o. 2 being perhaps the best; No. 4 bad, b u t better than th e others; Nos. 5 and 6 suspicious, b u t hardly to be condem ned.” T h e reply of the Osborne Engineerin g Co. w as as follow s: “ Sam ples Nos.
1, 2, 3, 4 and 5 w ere from different carloads of a brand of cem ent w hich we have been w atch ing for some tim e. These five sam ples w e had held in our lab orato ry for several weeks, m akin g retests of them from tim e to tim e as th ey becam e more aerated, to see how long it w ould be before the sam ples w ould boil. O f them , sam ples Nos. 1, 2 and 3 do n ot boil yet, w hile sam ples 4 and 5 have recen tly passed our boiling tests successfully.
Sam ple No. 6 is a sam ple of a different brand of cem ent w hich passed all our lab orato ry tests suc
cessfu lly.” In this case, as in the others, the m icro
scopic test picked ou t all th e poor cem ents b u t w as a little too severe on the good ones.
CA U SK S O F F R E E L IM E IN P O R T L A N D C E M E N T .
T a k in g the prem ise as established th a t free lim e should be absent from P ortland cem ent, it is in order to inquire how free lim e com es to be present in cem ent. There m ay be tw o reasons: first, the lim e in the raw m aterials m ay never h ave entered into com bination w ith th e silica, alum ina, etc., or second, it m ay b ave entered into proper com bination and been later separated ou t again in the free state.
In com plete com bination of lim e in th e cem ent is gen erally recognized as a com m on source of trouble. Tem perature and duration of burning, and fineness of the raw m aterial are all variab les affectin g this. I t has been shown here th a t under
burned cem ents alw ays contain free lim e and th a t a t no period of the burning, up to the proper tem perature, is free lim e absent. B u t th is proper tem perature is influenced b y the fineness of the raw m aterials, as w as shown b y C am p bell1 who, (E x p t. 104) being unable to m ake sound cem ent in our lab o rato ry rotary kiln from a sto ck raw m ix furnished b y a well-know n L ehigh V a lle y m ill even when the burning tem perature w as pushed to the lim it of i 6 i 2 ° C . , reground the m ix in a ja r m ill and then w as able (E x p t. 105) to get sound cem en t a t a tem perature 137 ° C . low er. T h e lac k of soundness in the first series he inferred m ust be due to free lime. M icroscopic investigation of
1 Jou r. A m . Chan. Soc., 25, 1103 (1903).
IO
sealed sam ples from these earlier experim ents has confirmed his diagnosis. Free lim e is to be found even in the highest-burned specim en of E x p t. 104. I t is present in E x p t. 105. No. 18 burned a t 14 5 1 ° w hich cem ent w as not sound.
F ree lim e is also, a t the present tim e, to be found in the clinker of No. 19 burned a t 14 7 50 which in spite of its d istin ctly underburned appearance, was able to pass the boiling test. Clinker No. 20 burned a t 150 1°, however, shows m erely the barest trace of lim e, it being altogether absent from some slides, and from th a t point up to the highest tem perature of 1627°, the cem ents are sound and free from lime.
T h e microscope thus confirm s the correctness of Professor Cam pbell’s earlier conclusion. T h e L ehigh V a lle y mill was able, because of th e longer exposure of the cem ent to high tem perature in its kilns, to m ake sound cem ent from raw m aterials w hich our lab orato ry kiln could not handle. These experim ents g ive a more ex a ct dem onstration of the fa ct know n to all th a t coarse grinding of the raw m ix produces bad cem ent, the disturbance being correctly laid to uncom bined lime.
T h e possibility of free lim e in cem ent being due to the separation of lim e w hich had been once in a sta te of com bination, is one w hich is n ot so generally accepted. W e h ave already mentioned th a t w e have m ade a m aterial of the 3 C a 0 .S i0 2 form ula containing no free lim e, b u t th a t this m aterial after fusion is found to contain free lime, as had been previously shown b y D a y , Shepherd and W right. I t is also know n th a t overburned cem ent frequ en tly dusts, a phenom ena characteris
tic of the ortho-silicate of lim e, 2 C a 0 .S i0 2. This ortho-silicate can h ave been form ed from a com pound richer in lim e only through the dissociation of th a t com pound w ith liberation of free lime.
T h e evidence on this point is n ot y e t conclusive, b u t is in accord w ith the hypothesis th a t cem ent is a t least in p art a solid solution whose viscosity even a t the burning tem perature retards chem ical action to such an e x ten t th a t equilibrium is not reached before the cem ent leaves the kiln. P o rt
land cem ent is an unstable transition product.
W ere it to be heated till equilibrium w as com plete, it would n o t alw ays be good cem ent.
A G IN G C E M E N T C O N T A IN IN G F R E E L IM E .
Som e d ata of the effect of aging com m ercial cem ents m ay be found in the report already given of the cem ents sent b y the Osborne E ngineering Co., where Nos. 1, 2 and 3 had been aerated in their lab oratory for several w eeks and were still
unsound. T h e y also contained free lim e as shown b y the m icroscope. Nos. 4 and 5 w hich had been aerated till th ey passed the boiling tests, still showed free lim e w ith the m icroscope, b u t w ere reported as decidedly b e tte r than the others. T h is brings up the question as to w hether the m icro
scope can d etect th e difference betw een a cem ent w hich is unsound and one w hich, origin ally con
tain in g free lim e, has becom e sound b y aging.
T h e question resolves itself into w hether under ord inary conditions of storing, Ca(OPI), is ever present in appreciable am ount or w h eth er the conversion into carbon ate is as rapid as the h y dration. E xp erim en ts on aeration of cem ent in thin layers in the lab orato ry indicates th a t the conversion into carbonate goes p ractica lly as fa st as the h ydration and th a t a cem ent thus aerated w ill n o t be entirely sound until th e m icroscope no longer detects lim e. W e h ave no evidence on the effect of aging cem ent in large piles, either as ground cem ent under cover or as clinker m oistened or exposed to the w eather. I t is en tirely con
ceivab le th a t the la tte r procedure m igh t g ive rise to form ation of calcium hydroxid e from even sound cem ent and cause erroneous conclusions to be draw n from the m icroscopic test.
S U M M A R Y .
T h e m icroscopic m ethod here described is simple and reliable for the identification of even sm all am ounts of free lim e in P ortla n d cem ent, b u t it is n ot a q u a n tita tiv e one. Cem ents w hich do n o t re- • spond to th is te st w ith in an hour can h ave 110 more than a harm less trace of free lim e. M ost of the sound com m ercial cem ents w hich h ave been e x am ined show no free lim e ; a few h ave shown traces of it. T h e m icroscopic te s t is more delicate than th e usual steam test, and cem ents w hich show som e free lim e under the m icroscope m ay successfully pass the standard tests for soundness b u t the p a t w ill be w eaker than if the cem ent w ere perfect.
Cem ent w hich com es from the kiln containing more than a trace of free lim e w ill not pass the boilin g test until the free lim e has been rem oved.
I f the free lim e is changed to carbon ate b y exposure to the air, the m icroscopic te st w ill still g iv e reliable indication of the q u a lity of the cem ent. If, through m ethod of aging, the lim e rem ains as h ydrate, th e m icroscopic test alone m igh t condem n a cem ent th a t had becom e p erfectly sound. In the same w a y , a sound cem ent w hich had been w et, m igh t be condem ned from m icroscopic evidence alone.
Free lim e is the chief cause of unsoundness in
T H E J O U R N A L O F 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 . n
Portland cem ent and, as e v e ry cem ent chem ist knows to his sorrow, is exasp eratin gly liable to appear in spite of his care. I t is alw ays present in underburned cem ent. I t is perhaps m ost fre quently due to lac k of fineness of grinding of th e raw m aterial. I t m ay be present in overburned cem ent, where lim e w hich had p revio u sly been com bined m ay h ave been throw n out of com bination a t the higher tem perature. W ith the boiling test as his only reliance the chem ist m ust alw ays w ork tw en ty-four hours behind his rotaries. T h e m icro
scopic test should, therefore, h ave a w ide range of usefulness in th e mill as the te st is so simple that it m ay be m ade, if desired, b y the burner who can thus control his prod u ct hour b y hour. T h e test should also be of valu e to th e inspector who m ay, w hen it is necessary to m ake a q u ick decision, perm it the use of those cem ents w hich show no free lim e, and hold for fu rth er in vestigation the doubtful samples.
Un i v e r s i t yo p Mi c h i g a n, S ept. 22, 1908.
NOTES ON ANTHRACITE PRODUCER PRAC
TICE.
B y Ge o r g eC. St o n e. R e ce iv e d S eptem b er 6 , 1908.
T h e statem en t is freq u en tly m ade th a t equal volum es of hydrogen and carbon m onoxide have p ractically the sam e heatin g pow er; and this, not only in the advertisem en ts of builders or producers, but in books and v e rb a lly b y those w ho should know better.
I t is true, th a t if equal volum es of hydrogen and carbon m onoxide are burned and the products of com bustion cooled to zero, the am ount of heat liberated b y the hydrogen is to the am ount of heat liberated b y the carbon m onoxide as 100 is to 98.86, b u t such a condition never occurs in furnace practice. T h e w ater produced b y the com bustion of the hydrogen a lw ay s leaves the furnace as va p o r and the heatin g pow ers are:
II : CO :: io o : 117.2
Then, too, the hydrogen flam e is m uch shorter than th a t of carbon m onoxide and it, therefore, tends to g ive a v e ry intense heat close to the ports, b u t does not h eat a large furnace as u niform ly as the latter. T h is fa cto r is often of m ore im por
tance than the difference in calorific pow er. T h e m akers of producers h ave encouraged the idea th at hydrogen is equal to carbon m onoxide for the reason th a t it is easier to run a producer w ith
a large am ount of steam as it prevents clinkering and saves m uch lab or in poking. W hen the gas is high in hydrogen, in consequence of much steam havin g been used, it usually carries an excessive am ount of w ater from undecoinposed steam and this carries off m uch heat to the sta ck in consequence of its v e ry high therm al ca p a city . I t is, I believe, safe to say th a t m ost producers are given more steam th an is econom ical. E nough m ust be used to p reven t clinkering to a degree th a t interferes w ith the w orking of the producer, b u t an yth in g in excess of th a t is detrim ental to econom y.
T h e calorific pow er of the gas, even w hen the w a ter is figured as vapor, is n o t an accu rate m easure of its usefulness. A cco u n t m ust also be taken of its therm al ca p a city , of the am ount of air re
quired to burn it and of the com position and therm al ca p a city of the w aste gases a t the tem perature a t w hich th ey leave the furnace. In other words, a com plete h eat balan ce m ust be stru ck a t w orking tem peratures.
A b o u t three years ago, w e increased the pro
ducers a t one of our plants, b y ab o u t three hun
dred per cent, and started a series of experim ents to endeavor to im prove our practice. A t th a t tim e, w e w ere using T a y lo r producers, seven feet in diam eter. T h e y were originally equipped w ith B ild t feeds, b u t these g ave so m uch trouble b y g e ttin g blocked b y pieces of coal a little larger than usual, and gave such poor distribution w ith the fine dam p anth racite used, th a t th ey were abandoned and a single plain feed hopper w ith bell w as sub
stituted . N um ber one b u ckw h eat coal w as used in these producers. T h e gas m ade is shown in colum n I of th e table. T h e CO is low and the CO, and II v e ry high; the gas is also v e ry w et.
T h is gas w as u n satisfactory in the furnaces as w ith it it w as v e ry difficult to regulate the d istri
b ution of the heat.
W e trained some b o ys to m ake gas analyses and set three of them to w ork on eight-hour shifts, m akin g hourly analyses of the gas supplied to each furnace. T h e good effect of this w as soon visible.
A s soon as the producer m en realized th a t the superintendent knew w h a t sort of w o rk th e y were doing all the tim e, th ey becam e m uch more care
ful and the gas becam e m ore uniform in q u ality.
T h e m oral effect of regular analyses is wonderful, the m en never kn ow q u ite how m uch inform ation the testin g gives and are m uch less lik ely to n eglect their w o rk or to p la y tricks.
T h e n e xt step w as to reduce the steam v e ry
largely. T h e result is shown in colum n II. T h e CO increased and the C0 2, H and H ,0 decreased g reatly. T h e calorific pow er dropped consider
a b ly, b u t the n et calories (under w orking condi
tions) dropped v e ry sligh tly. W ith the first gas over forty-nine per cent, of the heat w en t to the stack, w ith the second, o n ly forty-seven. T h e net result of this change w as an im provem ent in the furnace w ork, it being easier to regulate the h eat w ith the high CO low H gas than w ith the other.
U p to this tim e, w e had been burning num ber one bu ck w h eat; w e n e xt changed to num ber two and for the first few d ays had a great deal of trouble
feet six inches in diam eter. T h e shells of these can be revolved b y pow er w hile the top s and ash hoppers rem ain statio n ary. T h e ash tab les ordi
n arily revolve w ith the bodies b u t can be locked so th a t the revolution of th e upper p a rt grinds dow n th e ashes. T h e revo lvin g b o d y enables a m an to stand in one place and poke all p arts of th e producer as th ey com e around to him. E ach producer has tw o v e ry sm all feed hoppers placed eccentrically. T h is arrangem ent of eccen tric hop
pers and a revo lvin g b o d y gives a v e ry good dis
trib u tion of th e coal and to it our people a t the w orks a ttrib u te m uch of the success of these p ro ducers. T h e gas m ade b y these producers, as
Ta b l e.
I. I I . I I I .
C om position of gas, volu m e per cen t.
IV . V . V I.
c h4... . 0 .3 2 0 .3 0 0 .5 0 0 .4 0 1. 0 0 1 .00
C O ... . 19.52 2 3 .1 2 2 5 .3 0 2 7 .5 0 2 8 .3 0 3 1 .4 0
H ... . 18.4 5 11.8 4 11.4 0 1 1 . 2 0 1 0 .8 0 0 .8 0
C 02... . 9 .5 6 7 .8 8 5 .5 0 4 .5 0 3 .6 0 3 .2 0
N ... . 3 8 .1 7 5 1 .0 4 4 9 .4 0 4 9 .0 0 4 6 .6 0 6 3 .6 0
h2o... . 13.9 8 5 .8 2 7 .9 0 A ir required to burn (25 per cen t, excess).
7 .4 0 .9 .7 0 0.00
1.1 7 1 .0 8
W aste products, v 1.1 5 olu m e per cen t.
1 . 2 1 • 1 .2 3 1 .08
CO2... . 14.83 16.43 15.87 16.12 15.81 18.55
H 20 ... . 16.6 8 9 .5 9 10.3 0 9 .6 6 1 0 .6 9 1 .4 3
N ... . 66 .0 1 7 1 .6 0 7 1 .3 8 71.7 1 7 0 .9 2 7 7 .6 6
O . ... 2 .4 8 2 .3 8 2 .4 5 H ea t balance o f furnace.
2 .5 1 2 .5 8 2 .3 6
Sensible heat air a t 1 5 ° ... . 3 .9 3 3 .6 2 3 .8 7 4 .0 3 4 .3 5 3 .6 2
Sensible heat gas at 3 0 0 ° ... . 7 6 .0 6 71.85 71.71 7 1 .3 2 7 2.7 7 6 9 .9 2
A va ila b le calories in g a s ... . 8 0 5 .3 9 758.69 8 1 1 .5 9 8 5 0 .4 2 9 0 6 .2 0 777 .92
T ota l calories en terin g... . 885 .38 834 .16 8S7.17 9 2 5 .7 7 9 8 3 .3 2 8 5 1 .4 6
Calories in w aste gas a t 800 0. . . . 4 3 6 .9 8 391 .75 4 2 6 .9 7 4 3 4 .6 3 4 5 5 .8 2 4 0 7 .6 1
Calories used in fu r n a ce ... . 4 4 S .4 0 442.41 4 6 0 .2 0 4 9 1 .1 4 5 2 7 .5 0 4 4 3 .8 5
P er cen t, o f heat lo s t ... . 4 9 .3 5 4 6 .9 6 4 8 .1 3 4 6 .9 5 4 6 .3 6 4 7 .8 7
Per cen t, o f heat u s ed ... . 5 0 .6 5 5 3 .0 4 5 1 .8 7 5 3 .0 5 5 3 .6 4 5 2 .1 3
13. t. u . per c u b ic f o o t ... . 123 .4 116.2 124.3 130.3 139.1 1 1 9 .4
B . t. u. per cu b ic fo o t n e t ... , 6 S .7 6 7 .8 7 0 .5 R ela tive volu m es o f gas fo r equal effects.
7 5 .2 8 1 .0 6 8 . 1
Calorific p o w e r ... . 1 12. S 119.7 111 .9 106 .8 100.0 116.5
N et effect in fu rn a ce... . 117.9 119.5 114.6 107 .7 100.0 118.8
N et effect in fu rn a ce... . 100.0 103.7 9 7 .5 91 .4 8 4 .8 103.2
to g e t good gas; but, b y reducing the steam pres
sure and the thickness of the fuel bed and keeping after the men, in a short tim e w e were able to m ake th e gas shown in colum n I I I . T h is gas, still higher CO and low er C0 2, the H being ab out the same. T h e w ater is undesirably high, ow ing to the large am ount of m oisture in the fine coal, and the necessity of carryin g more steam th an we w ould like to, in order to p reven t the clinkering of the high-ash coal. A s will be seen, the calo
rific pow er and n e t heating pow er are higher than in the case of either of the others.
S h o rtly before changing to the sm aller coal, w e erected a num ber of H ughes producers, eight
soon as w e had learned how to run them , is shown in colum n IV . I t contain s co n sid erab ly more CO and a little less C 0 2 and ab o u t th e sam e II and H ,0 as the previous. T h e calorific pow er of this gas and its n e t effect are m uch higher th an for an y of the others.
Colum n V of the tab le gives the average gas m ade b y three sets of producers from M ay i s t to 15th, 1908. I t is still higher in CO and low er in CO , and H . I t contains m ore w a ter th an it should on accoun t of the v e ry rain y w eather durin g the tw o w eeks of th e run. N o tw ith stan d in g the excessive m oisture, th is gas show s th e highest calorific power, the largest per cent, of useful
