US 1659692 A
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Patented Feb, 21, 1928 anto .SrA ES PATENT, oFFicE.
ao snrmiuosns WARD KITCHEN, OF EAST ORANGE, NEW JERSEY.
METHOD or savrne FUEL:
The general object of this invention, which pertains to the preburning preparation of fuels, 'is effecting conservation of to other inventions of mine having fuel" economization for their purpose, for which patentsh ave been granted to me; but over all of WhlCh, the present invention is mad- Vance. Various of my 'copending applications relate to the preburning preparation and improvement of crude fuels, as Well as l tosimproved methods of burning them,
The present invention is the outcome of my'recognit-ion of the fact that there lsan economic desirability in effecting more or less of a change in the physical character of a large part of crude coal deposits before 7 their burning; because all coal deposits have at least some natural defects which inters fere with their economic use. Most deposits have marked physical defects. The vast fields of lignite-have an excessive water dontent, Bituminous coals have an excessive content of solvent volatile. Some hard coals such as the'Massachusetts and Rhode Island graphitic deposits, have so little volatile content that it is practically impossible to burn them alone in thir natural state. The bituminous and lignite coals have the defect of swelling and crumbling or slacking under mechanical handling and atmospheric or other heating influence; and even the best anthracite deals have the defect of so large an ashcontent, so that-in their use the fuel particles become externally coated with air excluding ashes during their descent thru'" I fuel-beds; which coats largely prevent the complete combustion of the. fuel-particles.
The result of this peculiarity is, that about one-half of the bulk of anthracite ashes is composed of unburned'carbon in the form .ofcinders that are shaken thru grate o enings. The present invention materially overcomes the defectivecharacter of crude" soft coals, by so treating them that fuelmasses of the prepared coals will'be so hardened and of retained porosity as to allow air and other gases to pass 'thru the fuel masses during their burning; yet the "hard- Application filed June 17,
1924. Serial No. 720,650.
ened prepared fuel-masseswill have adesirable B. t. u. concentration of heat producmg energy per unit of bulk. Also, that such prepared fuel-masses will not become excessively compacted and clogged in use" thru their crumbling and slacking in their burning; nor Wlll melt, fuserand form irregular non-uniform surfaces and masses of coke or slag, or form air funnels in the fuel-bed, or
' otherwise permit excess volumes of air for combustlon to pass thru the fuel-bed and dilutethe heat-of the burned gases of combustion. The smokelesscombustion of fuels that naturally are smoke forming is an object of this invention' In carrying out the main aim of the inv if vention, I preferably first secure material for the formation of a juxtaposed matrix or frame of fuelparticles that will be sufliciently hard in texture to prevent such compaction in their burning as always occurs in crude, natural, unchanged forms of soft coals if used alone and uncoked in fuel-beds; and also, that will be ,sufiiciently" hard to largely resist the impacting ,pressure of such softercrumbling or slacking fuels that may I be intermixed withthe harder fuel particles; This juxtaposed pressure-sustaining,
hardened matrix is of a character that requires greater heat to volatilize than any B. t: u. enriching interposed admixed solid soft fuel or than enriching fluid im re nants that I may use in preparing such ibe s Hence, the "harder constituents require a longer time to burn.- This fact necessitates providing for the burning outside of the fuel-bed of some low temperature volatilized matters, produced in the fuel-bed.
I. may use for'the fuel-mass-matrix or frame, hard uncoked fuels such as the Massachusetts and Rhode Island graphitic V coals that are not usable alone, because of being deficient in volatile content. gI"may useordinary-anthracite for the matrix, altho in the larger sized grades, that fuel is usually too expensive to be economically avail able. For some uses I intermix small sized 100 low cost anthracite, grades with hard anvalues, tar, and ammonia products.
the preparation of my fuels, becomes transformed into valuable "by-products in the form of burnable gases of various thermic In preparing a coked basis of my fuels,I may use high temperature carbonization, and
, drive ofi substantially all the volatilizable matters; for in doing so, it is more easily to thereafterenrich the coked basis of the fuel-- mass with a determined desirable content of concentrated heat-enriching constituent. Such high temperature cokes have a special valuefor use as absorbers and holders of low cost fuel oil impregnants for use in the generation of fixed burnable gases. Cokes of all degrees of hardness impregnated with fuel oil enrichers, have some value for burning completely for, heating, and in generating steam. The use of low temperature carbonized coke is a part of this invention.
'Such low temperature carbonized cokes,
have considerable value for generating'producer gas, or for oil gas, and for other purposes. In preparing my fuels, the methods Ikuse very materially facilitate the production of various cokes for various purposes. My copending application Ser. No.697,769, describes a combined method of producing cokes of various characters, and their usein generating burnable gases of various thermic values. Such prepared fuels are part of the present invention; for by coactive action in central plants thru gasifying the volatile in low cost coals I prepare a fuelgas of valuable character; I also utilize the heat of red hot coke in making water-gas.
And by simple'enrichment of the cokes, I secure a smokeless solid fuel, valuable for all heating purposes. By such coactive accomplishment I exercise such aggregate economies, that I prepare a fuel-gas of such low cost, that it can be used in internal combustion engines to generate power in successful competition with steam power; and also, secure hard fuels that will accomplish substantially equal results with all natural hard fuels in all household heating plants,
I 3 in electric lighting; and other economic results that need not be mentioned. The present invention therefore is a component part of that aggregate complex invention,
which is of great aggregate economic value.
In applying the principles of the present Invention, I follow to some extent, the principle used in the Bessemer method of steel production, in which all the carbon is burned out of the molten iron, and then enough carbon is restored to the iron to secure the hardening effect required for steel production. In the present invention, after. hardening the basic framework of my fuelmasses, I reconstitute in the particle or in the mass, more or less volatile that is desirable as an equivalent with what has been removed from the crude fuel in the hardenneaaeaa ing, coking process. This recbnstituting practice is not to the extent of incorporating volatile diffusive matters in or with coked particles, other than what may be absorbed into the coke porosities if oily enriching im} pregnants are used. Such fluid impregcause it is low in cost. An important economic feature ofimy invention is, thatI use low cost fuels that have relatively little demand, and hence can be purchased .at low prices. If I use un'slacked bituminous semibituminous or lignite coals to admix with harder .coked or uncoked fuels, I preferably mechanically comminute the unslacked- 'soft or semisoft fuel, and if Ido not use coke for the basic hard matrix of the juxtaposed fuel-mass, I add some coked smaller particles with the enriching soft bituminous particles in order to maintain a sufficient porosity in the fuel-mass, as well as to secure heat engendering intensity in burning harder .uncoked fuels that may be lacking in volatile content.
ungraded fuels of small particles rich in volatile, that I may admix with larger sized coke or hard coal particles, depends upon the use to which the fuel is to beapplied. For steam generation in; which I preferably use mechanically forced draft, and which I describe in several of my copending applications, the proportional amount'of admixed bituminous particles ,I use, may be "larger than if the fuel-mass is to be burned with a The amount of soft coal slack, or other less intense, andnonuniform naturally in-- duced draft. The depth of the fuel-bed used may also determine the amount of enrichment of the coked matrix. .I avoid admixing so many small soft particles in the interstices of the juxtaposed large particles as will interferetoo much with the draft tho in shallow fuel-beds thru which I mechanically force a draft, the entire interstices be tween the coke matrix may be filled with bituminous or ligni-te slack. In such instances, large amounts of low cost fuels of the smaller sized grades can be used economically, if due care is taken to burn outside of the bed, all
the burnable gases that are forced out of the fuel-bed by themechanical 'clraft. When I use fuel-dust in my admixtures to prevent flying dust and cinders in their use, I prefer to moisten the dust with water before admixing it with the coal particles of larger size;
banking purposes. a I may moisten the dust with fuel'oils for special purposes.
The admixing of the coked and uncoked fuel pa-rticles, I effect in any known way. For various uses, I have found that admixtures of one-quarter to one-third of the bulk of the fuel-mass ofsmall sized uncoked bituminous particles, to two-thirds of the bulk of the coked particles, usually burns well without smoke. I vary the depth of the fuelbed according to the use to which I apply the fuel, and according to the size of the fuel particles. I preferably maintain such depth I of the fuel-bed that no excess air for combustion can pass thru the fuel-bed under ordinary drafts; but I providefor thconr bustion of any unburned gases that escape from the fuel-bed, whether I use induced or mechanical draft,or both, in the burning of the fuel.
In igniting a fuel-bed of my prepared that case, care must be taken in not firing too large a mass at one timeof such oil enriched fuel. It may however be fed gradually, especially if fed onto and burned on a chain grate.
It will be understood that the fuels here'- in described and claimed are as a rule those which are mostly intended for complete burning in situ, and not for intentionally making producer gas, altho it is difficult, if not impossible, to preventthe formationof some producer gas in every fuel-bed, which gas escapes fromthe fuel-bed unless sufficient air for the combustion of the gas is passed entirely thru the fuel-bed or introduced above the fuel-bed. I aim to vprevent the passing of excess air thru the fuel-bed,
' thru preparing the textures of the fuelmasses, the depth of the fuel-bed, and the controlled amount of air that is allowed to pass into, or that is forced thru the fuel-bed.
It is important to provide for the complete I burning outside of the fuel-bed of any bui'n able gases that may pass out from the fuelbed. 7 use low temperatured carbonized cokes in mixtures for generating producer V gas. 7
] fuel-mass, is also important, as well as the method of its burning. It is desirable to sewell as its depth; and when possible the maintenance of a horizontal plane of the fuel-bed surface. This character in the fuelbed I largely secure thru the juxtaposed contact of hard, slow burning matrlx-partlcles of the fuel-bed, a large part of the heat generated in the fuel-bed being produced at the higher levels of the fuel-bed from smaller. particles of richer and more quickly burned fuel-particles interspersed between the 111K- taposed harder particles of the fuel-bed. This leaves an increased porosity of the fuelbed at lower levels.
Inasmuch as I preferably admlx with coked fuel, soft coal particles that have already become slacked or have beene mechanically comminuted, my prepared fuel maintains a less changeable physlcal character than is possible if unslacked or uncomminuted fuel particles are used. The
selection of size of particles not only preopen porosity which permits adequate access of air to and the complete combustion of the harder fuel particles at the lower levels. This prepared fuel maybe intermittently fed in blanket layers over the top surfaces of fuel-beds, and this acts mechanically to secure a high combustion temperature at lower levels of the bed, with comparatively 1 5 little opportunity to generate CO gas in the upper levels thru a recessive change of the 1 CO formed in the lower levels, which recessive change is so great a cause of losses in fuel-masses composed entirely of hard anthracite graded coals having a uniforrnl diffused content of volatile, burned w t draft entirely thru thefuel-bed, which diffused content in moderate presence in the fuel is the reason for the smokeless burning of anthracite coal. In my copending apphcation Ser. No. 717,197, filed May 31, 1924, I describe a dumping pit, into which partly burned coked fuel particles that have traveled over a chain grate, are dumped and are entirely burned in a fuel-bed so deep as to prevent excess air passing thru the fuel-bed, in conjunction with a controlled admixture of air forcombustion in the combustion space above the fuel-bed. This is a minor detail that however is important in securing the best economic results in saving fuel.
I emphasize the fact that preferably use coked fuel particles of relatively large size with ungraded smaller fuel particles 00011,
of such depth that excess air for combustion cannot readily pass thru the fuel-bed, but it also use mechanically forced draft to force air for combustion into the fuel-mass in proper amounts, and for admixing proper amounts of air for combustion with such unburned burnable gases as escape from the fuel-bed. I also control the pneumatic pressure inthe gas burning combustion spaces in which I burn gaseous fuel, as well as the rate of travel of the burned gases over the heating surfaces; and preferably do so, by more or less obstructing the burned-gas exitaperture from the combustion space, as'well as aim to secure a complete combustion of the gases at a level considerably below the .heating surfaces. ll may prepare fuels for generating producer gas thru the use of uncoked very hard graphitic coals, in admixture with more or less enriched coked particles, and in such proportions as to secure a desirable circulation of gases thru the fuel mass in the producer gas generator.
f secure the aim of controlling the porosity of the fuel mass in the producer generator thru an obstructive admixing fine of anthrasite dust and bitummous slack with coke 1n such proportions as will secure by obstruccoke, in conjunction .with a controlled forced lift draft, or maybe with a controlled obstructed closure of the exit aperture for'the gas from the producer. ll prepare a blanketing fuel, by utilizing low cost hard fuels admixed with fine coal dust or coke breeze or both, and thoroughly wetting such admixtures.
It should be noted that I use a large variety of fuel materials in forming my fuels, that maybe hard or soft in character; and that the particles used may all be ungraded, or partly graded and partly ungradcd. If a coked matrix is used, I partly rely on the porosity of the coke to pass draft thru the fuelmass, except when l impregnate the coke with fuel oils, in which case l generally do not admixnaturally rich soft coal particles "with the oil enriched coked particles. lfn the present invention 1 do not broadly claim the idea of having originated the mixmg'of fuels; but I do claim specifically, certain mixtures of fuels" having special use in certain instances; which use will effect fuel economies, and other advantages that hither to have not been secured in the art of fuel economization, especially when such admixed fuels are inventively combined with the methods of their preparation and burning.
resaeea For example; at the time of this writing, a strong effort is being made to burn low cost small sized buckwheat and smaller sizes of low cost anthracite fuels, by the use of mechanical draft forced thru the grate, and upward thru the fuel-bed. There is always a superabundance of such small sized grades of anthracite fuels in connection with anthracite mines. Efiort has been more or less successfully applied in burning such small sized fuels on grates of special con struction; but to burn them on grateshaving the usual sized grate openings thru which ashes can be easily shaken, it has been necessary to depend on the formation of a mat of combined ash and melted fuel parti cles located at a level above the grate line,
that will prevent the small sized particles be burned, are intercepted and are burned on that platform without sifting thru the grate. Hence, my idea is of considerable economic value. and a fuel mixture of that character is based on an inventive patent able idea.
lln claiming specific fuel mixtures of various kinds and of various sized fuel particles, it must be understood that when l claim particles of fuel of relatively large size in combination with fuel particles of relativelv small size, I do not restrict myself to an particular size or grade of either size of particles. Such limitation is not essential. The essential matter is that in case of hard coked particles enriched with uncoked small sized particles of soft coal rich in volatile, that the constituent amount of the admixed small "sized soft coal, is less in its aggregate bulk, than the bulk of coke or hard coal: for in that case, in the burning of the soft coal particles, they will not entirely fill the intel-spaces between the hard particles and thus clog and obstruct or entirely prevent lltb the passing of gases thru the fuel-mass. If k amounts, the crumbling and melting of the soft coal particles more or less clog or entirely obstruct the passage of draft thru the fuel-mass; the consequence of which is:
smoke formation or entire stoppage of combustion in the fuel-mass. This is especially so in connection with the use of natural induced drafts when ,applied to open gratesor deep fuel-beds occupying enclosed fire-boxes. In thin fuel-beds, smaller proportions of coke can be used if mechanical draft is forced upwardly thru the fuel-bed.
In the Ordinary method of burning particles ofisoft coals eifectively, the crude'particles are continually introduced into the zone of combustion and coked on traveling grates or in under-feed devices; butin either practice, a very considerable portion of the volatile thatis driven off from soft coals, is generally lost. In my invention an advance is claimed in the present and in my eight other copending applications, of making the cok ing of fuel a separate operation, and uitilizing the driven off volatile in producingfixed burnable gases of determined commercial value, as well as having a more cleanly condition, in which cleanly state the fuel-gas has an increased commercial value for use in the internal combustion engine in generating power as well as for use as a gaseous fuel to be applied in domestic practice in cookery, and in some cases, in Jbllll'lll'lg in heating devices.
In this combined practice, there is gained a large reduction in the cost of. power as compared with its generation thru-burning coal under steam boilers. In the future, ap-
plicant believes that substantially all power will be produced by the-burning of pre- -,pared low cost fuel-gases in gas engines;
while most of heating operations in large buildings will be effected by the burning of prepared solid fuels having as a framework or basis, hardened c'okes more or less enriched with low cost raw Soft coals either accidentally slackedor mechanically comminuted into such sizes that in their intermixture with hard coals or coke of larger size that are in more or less juxtapated con tact, the small enriching particles will only occupy a part of the interstices of and are. prevented from compaction by the juxtapaped contact of the larger sized'hard partic es. a
A-modification of the applied principles of this invention is the admixture of hard particles of coal of various graded ,sizes which are burned by intermittent applications of. the admixed hard fuels of. various sizes, a plied in successive coats onto the top sur aces of fuel-masses. There are large amounts of small sized anthracite coals such as buckwheat or smaller sizes, that can be eficiently burned in ordinary fuel burning devices constructed to burn deep beds of fuel that have ordinary grates already in existence. Byadding to such. small sized hard particles a minor bulk of hard coal'or coke of larger sized particles, even with the use of induced draft, a considerable amount of the smaller sizes and lower cost grades scribed and claimed.
can be utilized, and without the use of a mechanical draft. If forced mechanical draft is used, alarger amount of the small sized particles can be used in admixture with various bulks of hard large sized'particles which gravitate to the grate, while the smaller sizes areburned in the middle and .upper zones of the fuel-bechand their sifting thru the grate is prevented on that account. Applicant believes that this is an entirely new practice in connection with the art of fuel conservation and hence, that claimed fuel mixtures suitable for that particular use, are patentable and allowable to applicant.
There are large deposits of graphitic fuels that have slight or no volatile'content, that I without gasification of the impregnant holding coke. In this case, the porosity of the gas producing fuel-charge is maintained, and there is little or no carbonization on the interior surfaces of the retort.
In speaking of fuel particles of relatively small size, I usually mean, of considerably smaller size than the particles of hard coal; but I definitely state here that such admixture may be of hard particles of a size larger than chestnut sized grades and of smaller particles smaller in size than chestnut sized rades. In my banking fuels, in which lanketing coats are added to ignited fuelbeds, I designedly add crushed comminuted sizes of coke of any graded or of ungraded sizes, inasmuchas all of such fuel particles are hard, burn slowly, and can be fully im pregnated with Water, and help repress combustion. Some of the accompany ng claims relate to this particular class of mixed fuels. It will be understood that the character of thevarious mixtures specifically claimed is suitable for various purposes.
- The use of cokes of various degrees of carbonization in fuel mixtures, is of economic value for various purposes, in various proportions, in various mixed fuels. Those which I claim in this applicat on are of special value. Mixed fuels having coke of ,various sized particles and in various proportions, are specifically useful in giving porosity to fuel-masses, and for reducing excessive volatile content in fuel-masses as a whole; butif used alone and if produced by high temperature carbonization, they are too porous, too incombustible and are lacking in desirable volatile content for ordinary purposes of engendering heat, although they have useful value for metallurgical work.
I emphasize the factthat in the fuel mixtures in which I ordinarily use .coked particles of fuel ofrelatively large size as an larly in some cases, use anthracite buckwheat, or smaller grades of anthracite, in place of uncoked bituminous or lignite particles. Wherever such anthracite low cost fuels are available, they are usually preferable to utilize in place of soft bituminous or lignite small sized particles. The character of the fuels I use varies as to their place of origin, and largely depends upon their abundance or scarcity. Inasmuch as the soft coals are in very much greater abundance than hard coals'having limited desirable volatile content, their use would" naturally follow in districts where the soft fuels are plentiful, and then I would use coke in place of hard anthracite for the larger sized particles. (in the other hand, in the regions where the graphitic coals exist, they can be used with economic advantage" in place of coke.
But I wish to also emphasize the fact, that i where coke "is abundant, it can be used advantageously to a large extent in many fuel mixtures, especially in connection with mixtures suitable for producer gas manufacture and for banking fuels. For the latter, I may crush large sized coke particles and use i the crushed material intermixed with the fine dust of the harder coals and with some admixture of relatively large sized hard coal particles; the entiremixture to be well sat-1.
urated with water. Mixtures of that character act very advanta eously as banking fuels to use in domestic practice.
The proportionate amounts of large size and small size fuel particles that I admix, yary according to the graded size required or special purposes, as for example: cool:- ing, furnace use. banking, steam genera-= tion, and gas making. Also, as Well as ac= cording to the force of the draft used, whether natural-induced draft, or forced mechanical draft. Also, whether the fuelis to be partially coked onwhe fuel-bed, and whether the grates used are stationary or of traveling character. In case of the continuous feeding of the admixed fuel onto fuelhed, the uncoked soft constituent of the neeaeela admixtures may have a much larger proportion of soft small sized particles used. If there is to be no fuel-bed coking of the admixtures, it is preferable to have the smaller sized particles of the admixtures to be of low cost graded smaller sizes, or mixed screenings, or the dust of hard anthracite coal; all of which are low in cost.
In illustration of one form of admixed fuels I use, I cite: A fuel composed of admixed particles of coke and uncoked softfuel containing a high volatile content; the coke constituent comprising particles of relatively large size, and the uncoked constituent comprising-smaller sized particles than the large sized coke particles. In burning such a mixture, by feeding a relatively thick coat of the mixture on the fuel-bed, the mixture burns mostly from the under surface of the coat. The soft fuel burning first, leaves interspaces between the coke particles, and this allows for the passage of gases sideways to and outside of the borders of the newly fed coat of mixed fuel; and the gases and flame resulting from burning the under part of the newly fed coke, find more immediate contact with heating surfaces iii) than if the passage of gases were altogether anthracite dust in the melted volatile, causes the volatile and dust to adhere to the coked particles. This is largely due to the capillary action of the coke. The effect is a quicker opening up of porous places between the fuel particles in the fueled, and more quick and complete burning ofthe adherent constituents, In case of gasifying such mixtures in a gas-retort free from air, the same process occurs thru the effect of heating the retort, and when such adherent material is cooled either by steam or water, a useful form of fuel is the result, which is more brittle than'high temperature coke, and also comprises enriched burnable matter to a higher degree than the basic coke used.
What I claim as new is: 'l. A mixed fuel composed of prepared hard coal particles of relatively large graded size, and moistened coal particles of smaller size, the smaller sized particles being relatively rich in volatile and occupying only a portion of the interstices between the large sized particles,
2. A fuel composed of coke of graded large sized particles thoroughly mechanically admixed with uncoked coal of smaller sized graded particles.
3. A fuel composed of particles of coke in juxtaposed contact, and "uncoked coal aeuaaea richer in volatile than coke occupyingpart of the interstices of the particles in uxtaposed contact.
4.. A thoroughly mechanically mixed fuelinass composed of unground coarsely crushed coke of various sized particles, and
enriching uncoked fuel, said enriching uncoked fuel having a higher volatile content than the-coke, said mass having gas passing spaces in the interstices between the coke particles in the fuel-mass for the passage of draft thru the fuel-mass.
5. A composite fuel comprising graded uncoked particles of coal of relatively large size, and ungraded particles of coal of smaller size, said large sized particles being in juxtaposed contact and the uncoked particles of smaller size occupying only a portion of the interstices between the particles of larger size.
6. A composite fuelmass comprised of completely moistened and mechanically thoroughly admixed hard coal particles of relatively large size, coke particles of smaller size, and particles of uncoked coal dust.
7 A fuel-mass consisting of a matrix of hard pressure-resisting coal particles of substantially uniform graded size, said particles being in juxtaposed contact and ungraded uncoked coal particles of smaller size than but richer in volatile than the hard coal particles, said uncoked coal particles occupying a portion of the interstices of the hard pressure-resisting matrix.
8. A fuel-mass composed of dry particles of coke of relatively large size, having moistened coal dust adhering to the surfaces of thecoked particles. I
9. A banking fuel composed of admixed harduncoked relatively large coal particles, coke breeze, and anthracite coal dust, all of the constituents of said banking fuel being thoroughly moistened.
10. A fuel-mass composed of relatively large sized graded hard coal particles in juxtaposed contact, and soft coal particles rich in volatile admixed with coked particles, said admixed soft coal particles rich in volatile and coked particles substantially fully occupying the interstices between the hard coal partlcles.
11. A fuel-mass composed of a juxtaposed matrix of large sized hard coal particles deficient in volatile content, and admixed therewith, mixed uncoked soft coal and coked coal particles of smaller size than the hard coal particles, the smaller sized admixture occupying interstices between the hard large sized particles.
12. A composite fuel-mass of high temperature carbonized coked particles of coal of relatively large size, and smaller sized graded uncolred particles of coal interstitially placed between the coked articles of large size, the particles of sma ler size occupying only a part of the space between the high temperature coke particles and being unchanged in their crude volatile content but having a B. t. u. content greater than the B. t. u. content of the coked particles.
13. A fuel-mass com osed of coke of relatively large size, hig -volatile bituminous coal of relatively small sized particles, and anthracite dust.
14:. A fuel-mass composed of admixed particles of coke breeze, particles of an-- thracite coal of a graded size larger than rice size, and anth racite ,dust, said mixture being thoroughly moistened with water.
15. A fuel-mass composed of admixed particles of relatively large sized coke, particles of high-volatile bituminous coal, and anthracite dust.
JOSEPIf MOSES WARD KITCHEN.