US1726870A - Method and apparatus for burning fuels - Google Patents

Description

12 sheets-sheet 1- w. v.r= TRENT man um Armmus' Fon stimmte FUELS 5 Filed 'April 2s. 1926 lSept 3,1929. 1

a ...F... A@ 1 w im@ l Sept. 3, 1,929.l

W. E. TRENT A mob mlfmmus 'F93 BRNING Fumfs OOO ATTORNEYS.

Patented Sept. 3, 1929,

UNITED sTATEs .1,726,870 PATENT OFFICE.

WALTER E. TRENT, OF NEW YORK, Y.; ASSIGNOR TO TRENT PROCESS CORPORA- TION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

' :ami-ron AND APrARA'rUs'EoR BURNING FUE-Ls.

Application mea April 23, 192e. semi No. 104,112.

The inventionv relates to an'im Jroved method and apparatus forburning uels.

'The invention has particular` application to the burning of fue1s,consisting of a mix- V ture o'f pulverized coal and oil, althoughit is applicable to the burning of any fuel capable of being extruded.

" In carrying out the invention, if a fuel' consisting of pulverized' coal and oil of a 1u plastic consistency isbeing used the same is fed in a cylinder or tube form to the furnace while heated air passes through the fuel for the purpose of vaporizing volatiles therein and producing carbonized fuel particles as a residue which are fed with the air and vola- I TheV invention further comprises an im,

proved form of apparatus for carrying out the process above described.

Figure 1 isfa longitudinal sectional view partially shown in elevation of my improved urner. v 1 1 Figure 2 is a side elevation .thereofpshowing the wall of the furnace in section.

Figure' 3 is a sectional view taken along the line 3-f.-3 of Figure 1. y

Figure 4 is a. longitudinal sectional view of a modified form of my burner employing eut-ting knives to aid in breaking up the plas-y tic mass.

Figure 5 is a sectional view taken along 5--5 thereof.

Referring now more particularly to the drawings wherein like reference characters indicate corresponding parts, the numeral 1V designates the wall of a combustion chamber. To this wall there is-attached a burner 2. This burner-embodies a feedhopper' in the bottom of which there is a screw conveyor 4. The fuel introduced to this hopper may' vary, but I have found that a very successful fuel to use i s a mixture of coal ina fine state of sub-division of say 'from 100 to 200 meshes per vli. m=.ar inch thoroughly admixed with a hydrocarbon oil in such quantities as to be of a plastic consistency.. The conveyor is mounted on a hollow shaft 5 that is rotatably supported at the point 6 in the wall of the hopper A.' This shaft with thev conveyor is rotated by. the driving wheel 7 keyed thereto1 this wheel being driven by the gear 8 operated 'by a motor .9.- The hopper 3 at its outer end is threaded to the casting 10 by the Athreads 11. The entire burner is supported on the combustion chamber by the collar 12 having suitable means 13 for engaging and holding the collar to thepwall. The collar likewise has an air feedin opening 14 coinmunicating with the annu ar air passageVv 15 inthe casting, the inner side of this passage being. in communication withair discharging A slots 16 the annular chamber having apertures at the end thereof by meansof which air i's injected into the combustion chamber.

At one end the hollow shaft has a rotatable joint with the elbow 17. This elbow has an .air inlet 18 by means of which heated air is admitted to the interior 19 of the hollow rotatable shaft. The open end of the elbow may be directed downwardly as shown in Fig. 1 or upwardly as shownin Fig. 2, since the position of. this elbow is of no consequence. This air enters the hollow interior of the shaft under pressure and is preferably at a. temperature of say 300C" C. The hollow shaft near its o uter end is bell shaped as indicated by the reference character 20. The cone shaped portion of the shaft extends beyond the edge of the casting 10 and is provided with an 'imperforate inner annular wall 21 spaced from the outer-wall of the shaft. This inner wall is threaded to receive a valve 22 operated by a' stem 23 connected with a handle 24. The .inner [annular wall 21 is spaced from the outer. Wall of the hollow shaft to provide the air passage 25 through `which all theair passing through the hollow It will be observed jthat the hollow shaft i at a point slightly in front of the forward end of the annular wall 21 is formed with an annular flange or shoulder 27 which serves to coact'with the curved surfaces of the valve '22 to vary and regulate the quantity of the be furthermore apparent that the outer wall ofthe hollow shaft'is provided with a series f slots 28 extending therethrouglrfrom a,

I' point immediatelyin front of the valve to the outer part of the flared en d ofthe shaft and that a space 29 is provided between the end of the casting and that part 4of the annular end of the hollow shaft-to provide an outlet for fuel and gases as shown by the arrows in a. manner which will -be 'n ow d escribed.

In operating the device the hollow'shaft is rotated by the gear wheel 7. The-screw conveyor on this trudes or feeds a column of the plastic material from the container or hopper 3-'over the;A

surface of the hollow shaft. The surface of this shaft gradually increases in diameter by reason of the flaring end so that' this extruded.

column of material is gradually decreased in thickness as it proceeds'along theshaft. At

the same time a body of'hot airvunder any desired pressure and of a temperature of 'say 300 C. is continuously' admitted at the air inlet 18 to the hollow interior 1 9 of the'shaft. This air flows rapidly through this hollow 'shaft and p asses out through the seriesof slots 28 arranged therein. -It is app arent that the extruded column of 'fuel iscontinuously' 30 -shaft and that this column becomes thinner passing over the perforated end of the hollow as it approaches the'discharge point of the burner. There is no outlet for the air save through the slots 28. This heated air must therefore pass through the column of fuel thoroughly contacting therewith to vaporize the volatiles contained in the fuel and to leave a residue in theform of partially or totally carbonized particles. As the air moves under pressure these particles are sweptwith -the air and gases as indicated by the arrows 30 through the feed opening 29 into thecombustion'chamber and the gas vapors and fuel particles-are there consumed. By `reason of this passage of air through the film or tube of material the-volatiles are releasedfrom the fuel- `before it cnters the' combustioncham-v ber producing a fine,rich mixture of heated air, oil vapor and carbonizedfnarticles. Additional heated air may be' introduced to'the combustion chamber through the line 14, the` annular passage15, and the outlets 16 ofthe 'casting 10, when this air is needed to support combustion or to increase the efficiency of the burner.

The heated ai'r admitted to the hollow shaft should not be of a temperature so high as to cause a fusion of the fine-particles when it passes through the column of extruded fuel. 0

In other words, a coking of these particles should not 'occur'. I therefore preferably limit the temperature of this air to a point approximately 300 C. although this temperature will vary depending upon the coal being treated. While the hot air is depended shaft continuously exupon to Vdisintegrate the-column of 'fueljby .vaporizing' thefoil and'Wi-ll doy so in actual operation, I ma if desirable, as shown `4 and 5 placecutting pointsIor knives on the" bell shaped-endof .the hollow shaft` as indim cated bythe reference character 33 for the purpose ofassistinf in loosening-or releasing th material from the surface ofthe hollow shaft. It will be-fiirthermore observed that the valve 22 is employed for regulating the quantity of air discharging through the bell shaped end of the hollow shaft.'

While the`nvent1on` hasbeen particularly described as being-used .for feeding fuel of. a

plastic nature, it will be understood that'it is not limited to use-'With such'a' fuelfand is a- -licable to anyfuel that can be fed as a'. coll umn over the hollow shaft by the feeding conveyor.` It -will furthermore be understood 8.5 that gases otherthanfai can be admitted to the hollow 4interior of the-hollow shaft withi out departing from this invention. A further embodiment of this invention comprises the feeding of the plastic fuel tota 90. .i

zonewhere combustion is' limited so that gasiicatlon and vaporization may occur. f For instance, I may feed a mixture of pulver-izedv coal and oil containing soniev water. This mixture is ina plastic state 'and fed through 95 the' burner a's hereinabove described."A vThe 7 lieated air passing through 'the burner carries the steam, Vaporized volatiles and fuel. particles into the interior of the'combustion chamber 1. I regulate the quantity o'f this air as 100,

well as the quantity of auxiliaryv air admitted through the auxiliary air inlet 14 so 'that Conlditions of combustion in the combustion chamber are so perfect `that a low temperature distillation ofthe coal may be effected whereby only a portion of the 'generated gas and oil vapors are burned-so as to distillthe oil from the coal partlcles, which particles in this operation -are not' consumed. From the soealled combustion chamber, the coal particles and the gases may be collected in any well known manner. In other words, in .this

process combustion is renderedinoomnlete by controlling'the amount of secondary or auxiliary a1r admitted tothe chamber where- 115 charging the heated air, vaporizedz volatiles and fuel particles vinto a combustion zone for combustion.

2 .The method of burning a fuelof a. plastic consistency which consists in placing lsaid fuel mass in a tubularA shape, in heating the '13G A 1,726,9379 g n s tube to a temperature 'siitlicient to vaporize `volatilesto a combustion zone.

3. vThe method ofburning a ,'fuel, consist? ing of pulverized coal and oil of a plastic co'nsistency, consisting in feeding a column of such fuel toward a combustion zone, andin heating such column before it reaches the combustion zone to a temperature suicient tovaporize volatiles and form a residueeonsisting principally of carbonized fuel part1- cles, and in introducing such residue and the vaporized lvolatilesfto the combustion chamber for consumption. v.' f

4. The methodofburning a'fuel, consisting of pulverizedfcoal and oil of a plastic consistency, consisting in 'feeding a column of such fuel toward a combustion zone,"and in heating such column before it reaches theA combustion zone to a temperature suiiicient to Vaporize volatiles and .form a vresidue con` sisting principally of carbonized fuel -particles by passing a heated' gas througli su'chcol'- umn, and in introducing to the combustion chamber the residue consisting of the carbonized particles in suspension in said gas with the volatiles removed from the fuel. c

5. The 1method of burning fuel, cons1st1ng of pulverized coal and oil of a plastic con-1 sistency, which consists in directing a hollow column of such fuel toward a combustion chamber, in passing a heated gas into the interior -of such column to pass therethrough and vaporize volatiles contained therein, such gas serving to disintegrate and to carryr the released carbonaceous residue in suspension to a combustion chamber where such residue and the removed volatiles are consumed.

G. The methodof burning fuel, consisting of pulverized coal and oil of a plastic consist-v ency, which consists in directin a hollow column of such fuel toward a com ustion cliamber, in passing a. heated gas into the interior of such column to pass therethrough and vaporize volatiles contained therein, such gas serving to disintegrate and carry the released carbonaceous residue in suspension to a combustion chamber where suchresidue and the removed volatiles are consumed, ,and in supplying auxiliaries to such fuel at its point of combustion. g

7 The method of burning a fuel, consisting of pulverized coal and oil of a plastic consistency, consisting in continuously advancing a column of such fuel toward a combustion chamber, in feeding ahighly heated gas through-such columnof fuel before it reaches the combustion chamber to remove volatiles from the fuel and toA release the residuein'thevform of carbonized particles, in directing the heated stream of air to the combustion charn-y `ber to carry the released particles in suspension therein to said chamber where'they are 18. A burner comprising a'casing, means for feeding a column of fuel throughsaid casing tol'the combstion'chamber, means for introdclng preheated air tothe casing to heat said the pointof combustion'of the,` I

column of fuel to vaporize the volatiles cc n- A tained therein and tocarry said volatiles with thev combustion chamber.

v"BIA burnercomprising a casing, a -holl'ow element disposed therein, means'for advancing a column ofv fuel over said element, said. element having a plurality of a erturesnear one end, means for` feeding pre eated gas to the interior o f said element to pass through said apertures and the column of fuel surrounding the same -tovaporize the 'volatiles contained therein and'produce a. residue in the form of particles, and means for admitting the gas, particlesand the volatiles to a combustion chamber. 'l

10, VA method of burning fuel tiallyl plastic consistency which consists in feeding said fuel in a hollow form, in blowing 7'5' the released carbonac'eous 'fuel' particles to heated air through,l the' tube of Afuel to vapor.- l 1ze volat1les contained therein and at a rateto 5 disintegrate the. plastic tubular column and 1n d1scharg1ng the heated-air, vaporized volatiles and fuel particles into `a combustion zone d blowing a heated oxygen containing gas substantially radially outwards through said column to vaporize volatilescontained therein and at arate vsufficient', to disintegrate said column and carry the fuel particles thereof to a combustion lzone for combustion.

I 12. A method of burning a fuel-of plastic consistencyl which lconsists in feeding said fuel vmass 1n a tubular shape, in passing an oxygen containing gas substantiallyl radially outwards through said tube ata rate sufficient to disintegrate'said plastic mass andA to carry the particles thereof to a combustion zone for combustion. u

13. A method of burning a fuel of plastic consistency'which consistsin slowly advancing a mass of said fuel towards a combustion zone Aand 1n applying a sufficient quantityof an oxygen containing gas -to'said'mass prior to reaching said combustion zone at such a rate to' disintegrate said mass" and carry the particles thereoffto said combustion-zone.

14. A device for burning plastic fuel com- -prising a casing having a burner at one end thereof and 'an 'annular chamber therein,

means to advance a mass of. plastic fuel through said annular 'chamber towards said burner, means'to introduce air to the center portion of said casing within said annular chainber and to discharge airradially outwards through said plastic mass to carry fuel from the burner7 and means for discharging an auxiliary supply of air from said burner at-a point near its exit to comniingle at said noint'with the discharging fuel to assist coinv bustion thereof.A

1 5. A device for burning plastic fuel comprising a casing having a burner at one end thereof and an annular chamber therein,

means'to advance a mass of plastic fuelthrough said annular chamber towards said burner, means to introduce preheated air to the center pprtion of said ycasing within said annular chamber and to discharge air radially outwards through said plastic ma'ss to remove volatiles from said fuel-and additional means A vto aid in the disintegration of the advancing ".,fuel mass prior to its approach to said burner.

1.6.' 'A method of burning a fuel containing pulverized coal, comprising feeding a stream 'of' fuel through a burner, in blwing a heated gas throughvthe advancing stream of fuel to Asulstantially'vaporize the volatiles contained therein while in saidburner, in discharing heated gas, vaporized volatiles and. fuel particles-into a zone o f combustion Where combustion thereof occurs.

17. method of burning a fuel containing ulv'erized coal, comprising feeding a streaml Y.of -fuel .through a burner, in blowing a heated fg'as through the advancing-stream of fuel to substantially Vaporize the volatiles contained i, thereinwhile in said burner, in discharging heated gas, vaporized volatiles and fuelparticles into a zonefof. combustion where coinbustion thereof occurs and in admitting an auxiliary 'supply of heated 'gas to said fuel charge substantially at the point it enters the zone of combustion to thereof! 18. A method of'burning 'a fuel of plastic consistency, which consists in advancing such promote the combustion to the burner under f p ressure,'- in. directing such heated gas through thea'dvancing body of fuel to cause v aprizatio'n of the contained -fuel through a burner, in feeding heated gas volatiles therein and to carry fuel particles in suspension, and in introducing such gasvaporized volatiles and fuel particles into a com'- biistion chamber Where combustion thereof occurs.

' 19. A method of burning 'a'ifulel of plastic -j consistency, which consists in advancing such fuel through aburner, infeeding heatedga's;

to the burner under pressure, in directing such 'heated gas through the advancing body ofv fuel to cause vaporization of the contained volatiles therein and to carry fuel particles in sus'pension,A and in intro ucing such gas, va-

porized volatiles'andvfuel. particles into a.

-combustion chamber Where vcombustion.there'- umn of fuel travelling through-the burner to vaporizevolatiles contained therein and to carry the fuel particles in'v suspension, and in discharging said gas with containedvolatiles and fuel particles into a zone of combustion.

In testimony whereof I affix my signaturel WALTER E.` TRENT

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