CA1204999A - Low nox multifuel burner - Google Patents
Low nox multifuel burnerInfo
- Publication number
- CA1204999A CA1204999A CA000394058A CA394058A CA1204999A CA 1204999 A CA1204999 A CA 1204999A CA 000394058 A CA000394058 A CA 000394058A CA 394058 A CA394058 A CA 394058A CA 1204999 A CA1204999 A CA 1204999A
- Authority
- CA
- Canada
- Prior art keywords
- combustion
- fuel
- air
- annular passageway
- tubular conduit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D17/00—Burners for combustion conjointly or alternatively of gaseous or liquid or pulverulent fuel
- F23D17/007—Burners for combustion conjointly or alternatively of gaseous or liquid or pulverulent fuel liquid or pulverulent fuel
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
An improved multi-fuel burning method and apparatus having means for regulating the fuel-air mixture passing therethrough and including four separately controlled passage-ways delivering the air necessary for combustion and transport of the fuel while reducing the formation of nitrogen oxides.
An improved multi-fuel burning method and apparatus having means for regulating the fuel-air mixture passing therethrough and including four separately controlled passage-ways delivering the air necessary for combustion and transport of the fuel while reducing the formation of nitrogen oxides.
Description
~2~4~g~ ~
LOW NOX ~LTI-~UEL BURNER
''~AC'KG'ROUN~ HE INVENTION
Fi'e'l'd'o'f'I'n've'nt'i'oh The present ;nvention relates to fuel burners and more particularIy to an improved multi fuel burner for reduc;ng the formation of nitrogen oxides ~NOX) by lowering the com~ustion zone temperature, decreasing the uel and air mixing rate, and providing a reaucing atmosphere in the combustion zone.
I0 ,There is a present day gTowing concern with the immediate and lon~ *erm problems created by the rapid ;ncrease in air pollution resulting from the rise in the industrial civilization level throughout the world. With this concern comes an acute awareness that immediate steps must be taken to halt and reverse this upward trend in pollution. Great efforts are now being made by public and private economic sectors to develop measures for preventing potentially polluting particles and gases from being dis-charged into the atmosphere. One such source o atmospheric pollution,is the NQx present in the stack emission of fossil fuel fired steam generating units. , ' Nitric oxide ~NO) is an invisible, relatively harmless gas. However, as it passes through the vapor generatorlint,s the atmosphere and comes into contact with oxygen~ it partially reacts to orm nitrogen dioxide tNo2) or other oxides of nitro-gen collectively referred to as nitrogen oxides (NOX~. Nitro-gen dioxide is a yellow-~rown gas w~ich, in sufficient conc~n-trations, is toxic to animal and plant life. It is this gas which contributes to visible brownish haze in the atmosphere 3V near industrial and metropolitan centers.
.... .... ... ..... ....... . . ............... .... ...........................
~2~9g~ ( ~itrogen oxides are formed as a result of the reaction of nitrogen and oxygen at high temperatures and may be .hermal nitric o`xide and~or fuel nitric oxide. The former occurs from the reaction of the nitrogen and oxygen con-tained in the air supplied for the combustion o fossil fuel whereas the latter results from the reaction of the nitrogen contained in the fuel with the oxyge~ in the com~ustion air.
The rate at which thermal nitric oxide is formed is dependent upon any or a combination of the following variables:
Cl) flame ~emperature~ ~Z) residence time of the combustion gases in the high ~emperature zone and ~3) excess oxygen supply. The rate of formation of nitric oxide increases as flame temperature increases. However, the reaction takes time and a mixture of nitrogen and oxygen at a given tempera-ture for a very short time may produce less nitric oxide than the same mixture at a lower temperatureg but for a longer period of time. In vapor generators of the type discussed hereunder the combustion of fuel and air may generate flame ~0 temperatures in the order of 3,700F, the time-temperatuTe relationship governing the reaction is such that at 1~me temperatures below 2~900F no appreciable nitric oxide ~N0) is produced via the thermal mechanism, whereas above 2,900F
the rate of reaction increases rapidly.
The rate at which fuel nitric oxide is formed is prin-cipally dependent on the oxygen supply in the combustio~
zone and the nitric oxide production is minimized under a reducing atmosphere~ that is, a condition ~rhere the level of oxygen in the combustion zone is below that required or a ~0 complete burning of the fuel.
It is apparent from the foregoing discussion that the formation of thermal nitric oxide can be reduced by reduc-~2~99~ ( CASE ~344 ing'~flame temperatures in any degree and will be ~;n;~izedwith a ~lame temperature at or below 2,900~F and that the formation of fuel nitric oxide will be ~iniri zed by provid-ing a reducing atmosphere in the ignition zone.
With t~e advent of stricter emission controls, manu-facturers of uel ~urning equipment have been actively seeking methods of limiting t~e amount of NOX pollutants which are formed from the combustion of fossil fual.
Heretofore, their efforts ha~e been generally directed at either of the following two methods: two-stage combustion which calls for înitial firing with a aeficiency of air and the admission of the rem~ining ai~ needed for complete-combustion at a location remote rom the burneTs~ and another which calls for the addition o cooling surface ; 15 in the combustion zone Description of-*he Prior Art U.S. Pa~ent No. 3,7~8,796 discloses a method and apparatus for ~educing the formation o nitric oxides when burning pulverized fuel including th~ee separately controlled passageways deliv'ering the air necessary for combustion of the fuel.
. U.S. Patent No. 3,904,349 discloses a fluent fuel burning apparatus including three passageways and separate ' means for apportioning the flow of combustion air among the passages so as to achieve complete combustion of the fuel while reducing the forma~ion of nitrogen ~xides. The a~ore-mentioned patents, however, apply only to si.ngle fuel firing and are not equipped to provide for multi-fuel firing capabi-lities.
' SUMMAR~ OF THE INVEh~I'ON
The present invention provides an apparatus and method for reducing the formation o nitrogen oxides from a burner capable of firing multiple fuels in combination or singly and ac~ieving ~L2~4~99 complete burning of the carbonaceous fuels injected through the burner.
Accordingly, an improvement is made on fuel burners o~
the type disclosed in U.S. Patent No. 33788,796 and U.S. Paten$
No. 3,904,349 by providing an arrangement wherein multiple fuels can be combusted in this fuel burning apparatus either singly or in combination. The burner wall is ormed with an access opening for admitting that portion of the fuel burning apparatus which normally resides in the windbox whereas the furnace wall is formed with a burner port which accommodates the combining of fuel and air into a com~ustible mixtur~ and the ignition thereof. The multi~fuel burning apparatus includes a irst tubular conduit which is concentrically disposed about the central axis of the burner and having its outlet end open-ing adjacent to the burner port and its inlet end extending through the burner wall and terminating outside of the windbox.
The first tubular conduit defines a central passageway and serves to convey any carbonaceous fuel (secondary fuel) and a portion of the combustion air for discharge through the ~urner port into a combustion chamber. Means are provided for supplying a portion of the necessary combustion air to the first tubular conduit for discharge into the burner port.
Fox liquid fuels, independent means are pro~ided for injection of the fuel into the combustion chamber. For secondary solid Iuel, the fuel and a portion o~ the combustion air are in in~imate contact with the air serving to transport the solid fuel into the combustion chamber. A second tubular conduit ~hich is concentrically dispvsed about the first tubular conduit has its outlet end adjacent to the burner port and its inlet end extending through the burner wall and terminatîng outside the windbox. The second tubular conduit de~ines a central annular passageway and serves to convey pulverizel coal and transport air into the burner port. Means are provided ~04~
for supplying air entrained pulverized fuel to ~he second tubùlar conduit for discharge into the burner port. A first and second sleeve member are disposed within the windbox to direct combustion air therefrom to the burner port. The first sleeve member has a portion thereof concentrically spaced about the second ~ubular conduit to form an inner annular passageway therebetween and the second sleeve member has a portion thereof concentrically spaced about the first sleev~ member to form an outer annular passageway therebetween.
lQ Separate damper or register means are provided for apportioning the flow of windbox ir between the cen~ral passagewayJ the inner annular passageway, and the outer annular passageway.
A plurality of vanes is located in the inner annular passage-way and create a swirl to provide adequate mixing of the fuel and air.
An object of the invention is to provide a multi~uel burning apparatus wherein the initial burning of the fuel is conducted under a reducing atmosphere thereby inhibiting the formation of fuel nitric oxiae and providing the lower peak flame tempera~ure required to ~inimi ze the formation of the thermal nitric oxide.
Another object o the invention is to ~in; ;ze backmixing of the fuel and air in the base of the flame in order to limit . the ormation of nitrogen oxides and to promote flame stabili-zation.
Another object of the invention is to provide for the internal introduction of combustion air with respect to~the pul~erized coal in order to control flame shape and uel-air mix~ng.
A further object of the inYention is to admit the remain-ing air required for complete combustion along a flow pattern which surrounds the reducing and stabilizing zones and eventu-ally mixes with the fuel to complete its combustion.
., ~
A final object of the invention is to provide a means for the combustion of multiple fuels in combination or independently while minimizing the formation of nitric oxide from the combustion o~ the aforementioned fuels.
Thus, in accordance with the present invention there is provided a ~ulti-fuel burning apparatus comprising a first tubular conduit, defining a central passageway, opening in a burner port for discharge and combustion of fuel in a combustion chamber, means for supplying an air-conveyed solid carbonaceous fuel to the first tubular conduit for discharge and combustion in the combustion chamber, a liquid fuel assembly centrally e~tending within the first tubular conduit for discharge and combustion of a liquid fuel in the combustion chamber, a second tubular conduit concentrically disposed about the first tubular conduit and defining a central annular passageway for discharge and combustion of fuel in the combustion chamber, means for supplying air-conveyed pulverized coal to the central annular passageway, a first sleeve member having a portion thereof concentrically spaced about the second tubular conduit to form an inner annular passageway for delivery and supply of combustion air to the combustion chamber~ a second sleeve member having a portion thereo~
concentrically spaced about the first sleeve member to form an outer annular passageway for delivery and supply of additional combustion air to the combustion chamber, means for separately controlling the combustion air such that 5 to 10 percent of stoichiometric air is delivered to the central passageway, 15 to 30 percent to the central annular passageway, 22 to 35 percent to the inner annular passageway, and the remaining combustion air for complete combustion to the outer annular passageway for low NOX
production .
BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a schematic sectional elevational view of a ~apor generator using a multi-fuel burning apparatus embodying the invention.
FIGURE 2 is a sectional elevation view of tne multi-fuel burner embodying the invention.
~2(.~ g - 6a -FIGURE 3 is a transverse cross-sectional view taken along lines 3-3 of Figure 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGURE 1 there is shown a vapor generator 10 including water cooled walls 12 which define a furnace chamber or combustion space 14 to which carbon-aceous fuel and/or a pulverized coal fuel and air mixture is supplied by a multi-fuel burner 16.
After combustion has been completed in the furnace chamber 14, the heated gases flow upwardly around nose portion 18, over tubular secondary superheater 20, and thence downward throuqh convection pass 22 containing tubular prlmary superheater 24 and economizer 26. The gases leaving the convection pass 22 flow through tubes of an air heater 28 and are thereafter discharaed through a flue 30 and are subsequently discharged to the atmosphere by means not shown. It will be understood that the heated gases passing over the surfaces in the furnace 14, the superheaters 20 and 24, and the economizer 26 give up heat to the fluid flowing therethrough and that the gases passing through the air heater 28 give up additional heat to combustion air flowing over the tubes. A forced draft fan 32 supplies combustion air to the vapor generator and causes it to flow over the air heater tubes and around a plurality of baffles 34 and thence through a duct 36 for apportionment between branch ducts 38 and 40 respectively.
`
CAS~ 4344 The hea~ed air passing through duct 38 is delivered into a windbox 42 and represen~s a ma~or portion of the air necessary for combustion of the fuèl being discharged into burner port 50. The heated air passing through duct 40 is the transport air and the re~;ning portion of air necessary for combustion and is delivered in~o a primary air fan 52 wherein it is further pressurized and thereafter conveyed through a duct 54 into an air-swept type pulveri~ing apparatus 56.
The pulverîzed coal to be burned as primary fuel in the vapor gensrator 10 is delivered in raw form via pipe 58 from - raw coal storage bunker 60 to à feeder 62 in response to the load demand on the vapor generator 10 in a manner well known in the art. The pulverizer 56 grinds the raw caal to the desired particle size. The pressurized air flowing from th~
primary air fan 52 sweeps t~rough the pulverizer carrying therewith the g~ound coal particles for flow through a pipe 64 for discharge through the port 50 into the furnace chamber.
The secondary liquid~ fuel to be burned in vapor generator 10 is deli~ered to the burner via a pumping system (not ~hown) to liquid fuel burner assembly 79 in a channel independent of the central combustion air in a manner well known in the art.
A portion of the combustion air will be conveyed through duct `~
65 to the first tubular conduit 82 to burner port S0, by pass ing fan 53.
In the case of a secondary solid fuel which is supplied to the secondary solid fwel mixing chamber 83 through duct 81 in a manner well known in the art. The combustion air will be used to transport the solid fuel. A portion of the ~combus- -~
tion air will be conveyed through duct 65 to fan 53. After exiting fan 53, the combus*ion air ~ill flow thorugh duct 71 to secondary solid fuel mixing chamber 83 and t~en the solid fuel and air will flow through the first tubular conduit 82 to burner port S0. Windbox an 53 is in operation only for the solid secondary fuel application.
A damper 66 is associated with the forced drat fan 32 to regulate the quantity of air being admitted to the ~apor genera~or 10 in response to the load demand. A damper 68 is . . ... . . .. . . .. , ,,, .. ~,, " .................... .... .
:,' associated ~Tith the primary air fan 52 to regula~e the quantity of air being introduced to the pulverizing apparatus 56. A.
damper 67 is associated with windbox air fan 53 to regulate the quantity o~ combustion air being admitted to the fi~st .
~ubular conduit 82.
It will be appreciated that for the sake of clarity, the - .
drawings depict one multi-fuel burner associated with one pulverizer where in actual practice there may be more than one burner associated with the vapor generating unit.
Referring to FIGURE 2 there is shown the multi-fuel burner 16 arranged to fire throug~ the burner port 50, the latter being formed as a frustoconical throat diverging toward t~e furnace side of the wall 12 and ~eing fluid cooled b~
tubes 90. An outer ~urner wall 84, having an access opening 86, is spaced from the furnace wall 12. The space between the burner and furnace walls forms the wind~ox 42.
The multi-fuel burner ;ncludes a first tubular conduit 82 w~ich defines a central passageway 94 and extends through a - duct 64 and an access open;ng cover plate 88, across windbox 42 to a point adjacent the burner port 50. An optional liquid fuel burner assembly 79 is located coaxially wi~hin the firs~
tubular conduit 82 and is connected to a fluid fuel and atomi~-ing fluid supply lines (not shown). For the secondary solid fuel option, the inlet portion of first tubular conduit 82 is flow connected to secondary fuel mixing chamber 83. Mixing chamber 83 is flow connected to duct 71 which in turn is connected to windbox fan 53 and duct 65, the latter originating from windbox 42. Mixing chamber 83 is also flow connected to duct 81 through which the secondary solid fuel is supplied. IA damper 67 regulates the quantity and velocity of the combustion air flowing through the first tubular conduit 8~ and is used to control the flame shape and the mixing pattern of the fuel and .. . . air in urnace chamber 14 CFIGURE 1). A second.tu~ular conduit `~ m 80, concentrically spaced a~out the first tu~ular conduit 82~
3S ` ~ de~fines a central annular passageway 98 and extendx through the . . .
!
~2~9 ( g_ access cover plate 8~ across windbox 42 to a point adjacent to burner port 50. The inlet portion of ~he second tu~ular conduit 80 is flow connected to duct 64 which conveys pul-verized coal a~d a portion of the combustion air from pulveri-zer 56 ~FIGURE 1). An op~ional coal diffuser 134 is situated in the central annular passageway 98.
A first and second sleeve member 102 and 108 Tespectively are disposed within the windbox 42 to direct combustion air to the t~roat section formed within burner port 50. The first sleeve member 102 has a portion 102A concentrically spaced a~ou~ the outlet portion of the second tubular conduit 80 to ~orm an inner annular passageway 72 therebetween~ The remain-ing portion o sleeve 102 is in the form of a flange plate 102B extending laterally outward from the inlet end of portion 102A. An annular wall plate or ~ack plate 104 encircles the second tubular conduit and is connected thereto. The p~ates 104 and 102B are spaced from one another to form inlet 72A to inner annular passageway 72 which extends normal the~eto.
The inner periphery of annular plate 104 is also connected to 2a a sleeve-like section 106 extending along a segment of the out-let portion of the second tubular conduit 80 in contiguous surrounding relationship thereto. The second sleeve member 108 has a portion 108A concentrically spaced about the outlet end of sleeve portion 102A to form an outer annular passageway 74 there~etween. The remaining portion of sleeve 108 is in the form of a flange plate 108B extending laterally outward from the inlet end of portion 108A. An annular wall plate 110 encircles the slee~e poTtion 102A a~d is connected thqreto.
The plates 108B and 110 are spaced from one another to form the inlet 74A to outer passageway 74 which extends normal --thersto.
A plurality of dampers or registers 112 is located withln t~e inlet 72A to passa~eway 72 and is circumferentiall~ and equidistantly spaced and pivotally connected between and adja-cent ~he outer periphery of the plates 102B and 104. The dampers 112 are adapted to pi~ot ~etween open, closed and ~z~
- in~ermediate positions and are preferably interconnected through a lihkage train 114 so as to be collectively and simultaneously adjustable throu~h a shaft member 116 operatively connected ¦.
thereto and terminating ou~side of the windbox 42 and connected to a manually operated handle 118.
A plurality of dampers or registers 120 is located within the inlet 74A to passageway 74 and is circumferentially and equidistantly spaced and pivotally connected between and adja-cent the outer periphery of the plates 108B and llO. The dampers 120 are adapted to pivot between open, closed and inter-mediate positions and are preferably interconnected through a linkage train 122 so as to be collectively and simultaneously adjustable through a shaft member 124 operatively connected thereto and terminating outside of the windbox 42 and connected to a manually operated handle 126.
A plurality of vanes 128 is arranged in surrounding rela-tionship to the sleeve-like sec~ion 106 and is located within the inner annular passageway 72. The vanes 128 are equidis-` tantly spaced and preferably linked to one another so as to be collectively and simultaneously adjustable through a shaft member 130 operatively connected thereto and terminating out-side o~ the windbox 42 and connec.ted to a manually operated handle 132. The vanes 128 ha~e the principal function of imparting a rotational component to the combustion air flowing through the inner annular. passageway.
If desired, the shaft members 116, 124 and 130 may be suitably geared or otherwise connected to an operating means ~not shown) which would be responsive to an automatic co~trol.
An ignitor assembly 136 of known type extends through cover plate 88 and through the back plate 104 and terminates : at the discharge end o annular space 72. ~or certain secondary ... solid fuel, the ignitor assembly 136 can be located in the :~ central passageway 94 instead of the liquid fuel burner assembly .- 79. An obser~ation tube 138 extends through the co~er plate : 3~ 88 and through the ~ack plate 104 and terminates adjacent to the inside of back plate 104.
............ ..... .. .. .... ........
~IL2~9~
Li' Pigure 3 ahows a fragmented portion of the windbox side of cover plate 88 and includes the flange plate 108B with pivots 120A of the dampe~s 120 extending theTethrough. The sleeve portions 108A and 102A cooperate with one another to form the outer annular passageway 74 therebetween and the second tubular conduit 80 and sleeve portion 102A cooperate to form the inner annular passageway 72 therebetween. The passageway 72 houses the vanes 128. The second tubula~ conduit 80 and the first tubular conduit 82 define the outlet portion of the central annular passageway g8. An optional coal difuser 134 is situated in the central annular passageway 98. (Shown in Pigure 2). The first tubular conduit 82 defines the outlet portion of the central passageway 94. Located within the ~ central passageway 94 is-optional liquid fuel burne~ asse~bly 79. (Showr in Figure 2).
In the operation of t~e preferre~ embodiment, the fluid fuel to be burned in the furnace 14 is delivered via supply lines (not shown~, atomized within the fuel burner 16 and sprayed into the burner port 50. The secondary solid fuel to \~
be burned in the furnace 14 is deli~ered via duct 81 from a storage bunker ~not shown) utilizing the air from duct 71 to transport the solid fuel into the burner port 50. The quantity of air supplied being regulated by a camper device 67 to pro-vide sufficient air to transport the secondary fuel. The coal to be burned in the furnace 14 is delivered in raw form via pipe 58 from the raw coal storage bun~er 60 to the pulverizer feeder 62, which regulates the quantity of coal supplied to the pulverizer 56 in response to the load demand on thelvap~r generator 10 in a manner well known in the art. The pulverizer-56, being of the air-swept type, is supplied with pressurized combustion and transport air from a primary air fan 52, the quantity of air supplied being regulated by a damper device 68 to provide sufficient air to initiate ignition at tha burner discharge and provide adequate 1OW velocity $o insure a thorough sweeping of the pulverizer 56, coal burner pipe 64 ... . .. ...... ......... . ..... . . ~ .. .. ~ . . . ~ . .
~2~
and the central annular passage~ay 98.
The aiT required for combustion is delivered to the vapor generator by a forced draft fan 32 including a damper de~ice 66 which regulates the quantity of air in response to the load demand on the vapor generator 10 in a manne~ well known in the art. The combustion air is heated as it comes into indirect con~act with the flue gases flowing through the tubes of an air heater 28 and is thereater conveyed through a duct 36 to be apportioned between branch ducts 40 and 38, the former leads to the pul~erizer 56 as aforedescribed and the latter leads to the windbox whence the air is apportioned between the central passageway 94 via duct 65 and 71, the inner annular passageway 72, and the outer annula~ passageway 74.
From the foregoing, it will be noted that four separate flow paths are provided for admit-ting combustion air to the burner port 50; the central passageway 94, the central annular passageway 98, the inner annular passageway 72, and the outer annular passageway 74. The design of these flow paths and the regulation of the proportional amounts of air passing through these flow paths coupled with the enhancement of fuel-air dis-tribution and the shaping o~ the fuel discharge pattern consti-tute major features of the p~esent invention.
Under actual operation, it has been found that maintaining combustion air which flows through the central passageway 94 within a range of 5 to lO percent of stoichiometric air, that which flows through the central annular passageway 98 within - a range of 15 to 30 percent of stoichiometric air, and that which flows through the inner-annular passageway 72 within a range of 22 to 35 percent of stoichiometric air creates a stable,,igni-tion zone under a reducing atmosphere and pro~ides lower peak flame temperature. The combustion air whicn flows through the outer annular passageway 74 represents the air needed to complete the combustion of the fuel.
l~hile in accordance with the provlsions of the statutes 35 ~ there is illustrated and described herein a specific embodiment of the in~ention, those skilled in the art will understand that ....... ................. ........... , ... ... ,,.,,.,,,",.. ~.;
~, ~ 4~
cnanges may be made in the form of the inven~ion covered by the claims, and that certain features of the invention may sometimes be uced to advantage without a corresponding use o the other features.
., , i,
LOW NOX ~LTI-~UEL BURNER
''~AC'KG'ROUN~ HE INVENTION
Fi'e'l'd'o'f'I'n've'nt'i'oh The present ;nvention relates to fuel burners and more particularIy to an improved multi fuel burner for reduc;ng the formation of nitrogen oxides ~NOX) by lowering the com~ustion zone temperature, decreasing the uel and air mixing rate, and providing a reaucing atmosphere in the combustion zone.
I0 ,There is a present day gTowing concern with the immediate and lon~ *erm problems created by the rapid ;ncrease in air pollution resulting from the rise in the industrial civilization level throughout the world. With this concern comes an acute awareness that immediate steps must be taken to halt and reverse this upward trend in pollution. Great efforts are now being made by public and private economic sectors to develop measures for preventing potentially polluting particles and gases from being dis-charged into the atmosphere. One such source o atmospheric pollution,is the NQx present in the stack emission of fossil fuel fired steam generating units. , ' Nitric oxide ~NO) is an invisible, relatively harmless gas. However, as it passes through the vapor generatorlint,s the atmosphere and comes into contact with oxygen~ it partially reacts to orm nitrogen dioxide tNo2) or other oxides of nitro-gen collectively referred to as nitrogen oxides (NOX~. Nitro-gen dioxide is a yellow-~rown gas w~ich, in sufficient conc~n-trations, is toxic to animal and plant life. It is this gas which contributes to visible brownish haze in the atmosphere 3V near industrial and metropolitan centers.
.... .... ... ..... ....... . . ............... .... ...........................
~2~9g~ ( ~itrogen oxides are formed as a result of the reaction of nitrogen and oxygen at high temperatures and may be .hermal nitric o`xide and~or fuel nitric oxide. The former occurs from the reaction of the nitrogen and oxygen con-tained in the air supplied for the combustion o fossil fuel whereas the latter results from the reaction of the nitrogen contained in the fuel with the oxyge~ in the com~ustion air.
The rate at which thermal nitric oxide is formed is dependent upon any or a combination of the following variables:
Cl) flame ~emperature~ ~Z) residence time of the combustion gases in the high ~emperature zone and ~3) excess oxygen supply. The rate of formation of nitric oxide increases as flame temperature increases. However, the reaction takes time and a mixture of nitrogen and oxygen at a given tempera-ture for a very short time may produce less nitric oxide than the same mixture at a lower temperatureg but for a longer period of time. In vapor generators of the type discussed hereunder the combustion of fuel and air may generate flame ~0 temperatures in the order of 3,700F, the time-temperatuTe relationship governing the reaction is such that at 1~me temperatures below 2~900F no appreciable nitric oxide ~N0) is produced via the thermal mechanism, whereas above 2,900F
the rate of reaction increases rapidly.
The rate at which fuel nitric oxide is formed is prin-cipally dependent on the oxygen supply in the combustio~
zone and the nitric oxide production is minimized under a reducing atmosphere~ that is, a condition ~rhere the level of oxygen in the combustion zone is below that required or a ~0 complete burning of the fuel.
It is apparent from the foregoing discussion that the formation of thermal nitric oxide can be reduced by reduc-~2~99~ ( CASE ~344 ing'~flame temperatures in any degree and will be ~;n;~izedwith a ~lame temperature at or below 2,900~F and that the formation of fuel nitric oxide will be ~iniri zed by provid-ing a reducing atmosphere in the ignition zone.
With t~e advent of stricter emission controls, manu-facturers of uel ~urning equipment have been actively seeking methods of limiting t~e amount of NOX pollutants which are formed from the combustion of fossil fual.
Heretofore, their efforts ha~e been generally directed at either of the following two methods: two-stage combustion which calls for înitial firing with a aeficiency of air and the admission of the rem~ining ai~ needed for complete-combustion at a location remote rom the burneTs~ and another which calls for the addition o cooling surface ; 15 in the combustion zone Description of-*he Prior Art U.S. Pa~ent No. 3,7~8,796 discloses a method and apparatus for ~educing the formation o nitric oxides when burning pulverized fuel including th~ee separately controlled passageways deliv'ering the air necessary for combustion of the fuel.
. U.S. Patent No. 3,904,349 discloses a fluent fuel burning apparatus including three passageways and separate ' means for apportioning the flow of combustion air among the passages so as to achieve complete combustion of the fuel while reducing the forma~ion of nitrogen ~xides. The a~ore-mentioned patents, however, apply only to si.ngle fuel firing and are not equipped to provide for multi-fuel firing capabi-lities.
' SUMMAR~ OF THE INVEh~I'ON
The present invention provides an apparatus and method for reducing the formation o nitrogen oxides from a burner capable of firing multiple fuels in combination or singly and ac~ieving ~L2~4~99 complete burning of the carbonaceous fuels injected through the burner.
Accordingly, an improvement is made on fuel burners o~
the type disclosed in U.S. Patent No. 33788,796 and U.S. Paten$
No. 3,904,349 by providing an arrangement wherein multiple fuels can be combusted in this fuel burning apparatus either singly or in combination. The burner wall is ormed with an access opening for admitting that portion of the fuel burning apparatus which normally resides in the windbox whereas the furnace wall is formed with a burner port which accommodates the combining of fuel and air into a com~ustible mixtur~ and the ignition thereof. The multi~fuel burning apparatus includes a irst tubular conduit which is concentrically disposed about the central axis of the burner and having its outlet end open-ing adjacent to the burner port and its inlet end extending through the burner wall and terminating outside of the windbox.
The first tubular conduit defines a central passageway and serves to convey any carbonaceous fuel (secondary fuel) and a portion of the combustion air for discharge through the ~urner port into a combustion chamber. Means are provided for supplying a portion of the necessary combustion air to the first tubular conduit for discharge into the burner port.
Fox liquid fuels, independent means are pro~ided for injection of the fuel into the combustion chamber. For secondary solid Iuel, the fuel and a portion o~ the combustion air are in in~imate contact with the air serving to transport the solid fuel into the combustion chamber. A second tubular conduit ~hich is concentrically dispvsed about the first tubular conduit has its outlet end adjacent to the burner port and its inlet end extending through the burner wall and terminatîng outside the windbox. The second tubular conduit de~ines a central annular passageway and serves to convey pulverizel coal and transport air into the burner port. Means are provided ~04~
for supplying air entrained pulverized fuel to ~he second tubùlar conduit for discharge into the burner port. A first and second sleeve member are disposed within the windbox to direct combustion air therefrom to the burner port. The first sleeve member has a portion thereof concentrically spaced about the second ~ubular conduit to form an inner annular passageway therebetween and the second sleeve member has a portion thereof concentrically spaced about the first sleev~ member to form an outer annular passageway therebetween.
lQ Separate damper or register means are provided for apportioning the flow of windbox ir between the cen~ral passagewayJ the inner annular passageway, and the outer annular passageway.
A plurality of vanes is located in the inner annular passage-way and create a swirl to provide adequate mixing of the fuel and air.
An object of the invention is to provide a multi~uel burning apparatus wherein the initial burning of the fuel is conducted under a reducing atmosphere thereby inhibiting the formation of fuel nitric oxiae and providing the lower peak flame tempera~ure required to ~inimi ze the formation of the thermal nitric oxide.
Another object o the invention is to ~in; ;ze backmixing of the fuel and air in the base of the flame in order to limit . the ormation of nitrogen oxides and to promote flame stabili-zation.
Another object of the invention is to provide for the internal introduction of combustion air with respect to~the pul~erized coal in order to control flame shape and uel-air mix~ng.
A further object of the inYention is to admit the remain-ing air required for complete combustion along a flow pattern which surrounds the reducing and stabilizing zones and eventu-ally mixes with the fuel to complete its combustion.
., ~
A final object of the invention is to provide a means for the combustion of multiple fuels in combination or independently while minimizing the formation of nitric oxide from the combustion o~ the aforementioned fuels.
Thus, in accordance with the present invention there is provided a ~ulti-fuel burning apparatus comprising a first tubular conduit, defining a central passageway, opening in a burner port for discharge and combustion of fuel in a combustion chamber, means for supplying an air-conveyed solid carbonaceous fuel to the first tubular conduit for discharge and combustion in the combustion chamber, a liquid fuel assembly centrally e~tending within the first tubular conduit for discharge and combustion of a liquid fuel in the combustion chamber, a second tubular conduit concentrically disposed about the first tubular conduit and defining a central annular passageway for discharge and combustion of fuel in the combustion chamber, means for supplying air-conveyed pulverized coal to the central annular passageway, a first sleeve member having a portion thereof concentrically spaced about the second tubular conduit to form an inner annular passageway for delivery and supply of combustion air to the combustion chamber~ a second sleeve member having a portion thereo~
concentrically spaced about the first sleeve member to form an outer annular passageway for delivery and supply of additional combustion air to the combustion chamber, means for separately controlling the combustion air such that 5 to 10 percent of stoichiometric air is delivered to the central passageway, 15 to 30 percent to the central annular passageway, 22 to 35 percent to the inner annular passageway, and the remaining combustion air for complete combustion to the outer annular passageway for low NOX
production .
BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a schematic sectional elevational view of a ~apor generator using a multi-fuel burning apparatus embodying the invention.
FIGURE 2 is a sectional elevation view of tne multi-fuel burner embodying the invention.
~2(.~ g - 6a -FIGURE 3 is a transverse cross-sectional view taken along lines 3-3 of Figure 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGURE 1 there is shown a vapor generator 10 including water cooled walls 12 which define a furnace chamber or combustion space 14 to which carbon-aceous fuel and/or a pulverized coal fuel and air mixture is supplied by a multi-fuel burner 16.
After combustion has been completed in the furnace chamber 14, the heated gases flow upwardly around nose portion 18, over tubular secondary superheater 20, and thence downward throuqh convection pass 22 containing tubular prlmary superheater 24 and economizer 26. The gases leaving the convection pass 22 flow through tubes of an air heater 28 and are thereafter discharaed through a flue 30 and are subsequently discharged to the atmosphere by means not shown. It will be understood that the heated gases passing over the surfaces in the furnace 14, the superheaters 20 and 24, and the economizer 26 give up heat to the fluid flowing therethrough and that the gases passing through the air heater 28 give up additional heat to combustion air flowing over the tubes. A forced draft fan 32 supplies combustion air to the vapor generator and causes it to flow over the air heater tubes and around a plurality of baffles 34 and thence through a duct 36 for apportionment between branch ducts 38 and 40 respectively.
`
CAS~ 4344 The hea~ed air passing through duct 38 is delivered into a windbox 42 and represen~s a ma~or portion of the air necessary for combustion of the fuèl being discharged into burner port 50. The heated air passing through duct 40 is the transport air and the re~;ning portion of air necessary for combustion and is delivered in~o a primary air fan 52 wherein it is further pressurized and thereafter conveyed through a duct 54 into an air-swept type pulveri~ing apparatus 56.
The pulverîzed coal to be burned as primary fuel in the vapor gensrator 10 is delivered in raw form via pipe 58 from - raw coal storage bunker 60 to à feeder 62 in response to the load demand on the vapor generator 10 in a manner well known in the art. The pulverizer 56 grinds the raw caal to the desired particle size. The pressurized air flowing from th~
primary air fan 52 sweeps t~rough the pulverizer carrying therewith the g~ound coal particles for flow through a pipe 64 for discharge through the port 50 into the furnace chamber.
The secondary liquid~ fuel to be burned in vapor generator 10 is deli~ered to the burner via a pumping system (not ~hown) to liquid fuel burner assembly 79 in a channel independent of the central combustion air in a manner well known in the art.
A portion of the combustion air will be conveyed through duct `~
65 to the first tubular conduit 82 to burner port S0, by pass ing fan 53.
In the case of a secondary solid fuel which is supplied to the secondary solid fwel mixing chamber 83 through duct 81 in a manner well known in the art. The combustion air will be used to transport the solid fuel. A portion of the ~combus- -~
tion air will be conveyed through duct 65 to fan 53. After exiting fan 53, the combus*ion air ~ill flow thorugh duct 71 to secondary solid fuel mixing chamber 83 and t~en the solid fuel and air will flow through the first tubular conduit 82 to burner port S0. Windbox an 53 is in operation only for the solid secondary fuel application.
A damper 66 is associated with the forced drat fan 32 to regulate the quantity of air being admitted to the ~apor genera~or 10 in response to the load demand. A damper 68 is . . ... . . .. . . .. , ,,, .. ~,, " .................... .... .
:,' associated ~Tith the primary air fan 52 to regula~e the quantity of air being introduced to the pulverizing apparatus 56. A.
damper 67 is associated with windbox air fan 53 to regulate the quantity o~ combustion air being admitted to the fi~st .
~ubular conduit 82.
It will be appreciated that for the sake of clarity, the - .
drawings depict one multi-fuel burner associated with one pulverizer where in actual practice there may be more than one burner associated with the vapor generating unit.
Referring to FIGURE 2 there is shown the multi-fuel burner 16 arranged to fire throug~ the burner port 50, the latter being formed as a frustoconical throat diverging toward t~e furnace side of the wall 12 and ~eing fluid cooled b~
tubes 90. An outer ~urner wall 84, having an access opening 86, is spaced from the furnace wall 12. The space between the burner and furnace walls forms the wind~ox 42.
The multi-fuel burner ;ncludes a first tubular conduit 82 w~ich defines a central passageway 94 and extends through a - duct 64 and an access open;ng cover plate 88, across windbox 42 to a point adjacent the burner port 50. An optional liquid fuel burner assembly 79 is located coaxially wi~hin the firs~
tubular conduit 82 and is connected to a fluid fuel and atomi~-ing fluid supply lines (not shown). For the secondary solid fuel option, the inlet portion of first tubular conduit 82 is flow connected to secondary fuel mixing chamber 83. Mixing chamber 83 is flow connected to duct 71 which in turn is connected to windbox fan 53 and duct 65, the latter originating from windbox 42. Mixing chamber 83 is also flow connected to duct 81 through which the secondary solid fuel is supplied. IA damper 67 regulates the quantity and velocity of the combustion air flowing through the first tubular conduit 8~ and is used to control the flame shape and the mixing pattern of the fuel and .. . . air in urnace chamber 14 CFIGURE 1). A second.tu~ular conduit `~ m 80, concentrically spaced a~out the first tu~ular conduit 82~
3S ` ~ de~fines a central annular passageway 98 and extendx through the . . .
!
~2~9 ( g_ access cover plate 8~ across windbox 42 to a point adjacent to burner port 50. The inlet portion of ~he second tu~ular conduit 80 is flow connected to duct 64 which conveys pul-verized coal a~d a portion of the combustion air from pulveri-zer 56 ~FIGURE 1). An op~ional coal diffuser 134 is situated in the central annular passageway 98.
A first and second sleeve member 102 and 108 Tespectively are disposed within the windbox 42 to direct combustion air to the t~roat section formed within burner port 50. The first sleeve member 102 has a portion 102A concentrically spaced a~ou~ the outlet portion of the second tubular conduit 80 to ~orm an inner annular passageway 72 therebetween~ The remain-ing portion o sleeve 102 is in the form of a flange plate 102B extending laterally outward from the inlet end of portion 102A. An annular wall plate or ~ack plate 104 encircles the second tubular conduit and is connected thereto. The p~ates 104 and 102B are spaced from one another to form inlet 72A to inner annular passageway 72 which extends normal the~eto.
The inner periphery of annular plate 104 is also connected to 2a a sleeve-like section 106 extending along a segment of the out-let portion of the second tubular conduit 80 in contiguous surrounding relationship thereto. The second sleeve member 108 has a portion 108A concentrically spaced about the outlet end of sleeve portion 102A to form an outer annular passageway 74 there~etween. The remaining portion of sleeve 108 is in the form of a flange plate 108B extending laterally outward from the inlet end of portion 108A. An annular wall plate 110 encircles the slee~e poTtion 102A a~d is connected thqreto.
The plates 108B and 110 are spaced from one another to form the inlet 74A to outer passageway 74 which extends normal --thersto.
A plurality of dampers or registers 112 is located withln t~e inlet 72A to passa~eway 72 and is circumferentiall~ and equidistantly spaced and pivotally connected between and adja-cent ~he outer periphery of the plates 102B and 104. The dampers 112 are adapted to pi~ot ~etween open, closed and ~z~
- in~ermediate positions and are preferably interconnected through a lihkage train 114 so as to be collectively and simultaneously adjustable throu~h a shaft member 116 operatively connected ¦.
thereto and terminating ou~side of the windbox 42 and connected to a manually operated handle 118.
A plurality of dampers or registers 120 is located within the inlet 74A to passageway 74 and is circumferentially and equidistantly spaced and pivotally connected between and adja-cent the outer periphery of the plates 108B and llO. The dampers 120 are adapted to pivot between open, closed and inter-mediate positions and are preferably interconnected through a linkage train 122 so as to be collectively and simultaneously adjustable through a shaft member 124 operatively connected thereto and terminating outside of the windbox 42 and connected to a manually operated handle 126.
A plurality of vanes 128 is arranged in surrounding rela-tionship to the sleeve-like sec~ion 106 and is located within the inner annular passageway 72. The vanes 128 are equidis-` tantly spaced and preferably linked to one another so as to be collectively and simultaneously adjustable through a shaft member 130 operatively connected thereto and terminating out-side o~ the windbox 42 and connec.ted to a manually operated handle 132. The vanes 128 ha~e the principal function of imparting a rotational component to the combustion air flowing through the inner annular. passageway.
If desired, the shaft members 116, 124 and 130 may be suitably geared or otherwise connected to an operating means ~not shown) which would be responsive to an automatic co~trol.
An ignitor assembly 136 of known type extends through cover plate 88 and through the back plate 104 and terminates : at the discharge end o annular space 72. ~or certain secondary ... solid fuel, the ignitor assembly 136 can be located in the :~ central passageway 94 instead of the liquid fuel burner assembly .- 79. An obser~ation tube 138 extends through the co~er plate : 3~ 88 and through the ~ack plate 104 and terminates adjacent to the inside of back plate 104.
............ ..... .. .. .... ........
~IL2~9~
Li' Pigure 3 ahows a fragmented portion of the windbox side of cover plate 88 and includes the flange plate 108B with pivots 120A of the dampe~s 120 extending theTethrough. The sleeve portions 108A and 102A cooperate with one another to form the outer annular passageway 74 therebetween and the second tubular conduit 80 and sleeve portion 102A cooperate to form the inner annular passageway 72 therebetween. The passageway 72 houses the vanes 128. The second tubula~ conduit 80 and the first tubular conduit 82 define the outlet portion of the central annular passageway g8. An optional coal difuser 134 is situated in the central annular passageway 98. (Shown in Pigure 2). The first tubular conduit 82 defines the outlet portion of the central passageway 94. Located within the ~ central passageway 94 is-optional liquid fuel burne~ asse~bly 79. (Showr in Figure 2).
In the operation of t~e preferre~ embodiment, the fluid fuel to be burned in the furnace 14 is delivered via supply lines (not shown~, atomized within the fuel burner 16 and sprayed into the burner port 50. The secondary solid fuel to \~
be burned in the furnace 14 is deli~ered via duct 81 from a storage bunker ~not shown) utilizing the air from duct 71 to transport the solid fuel into the burner port 50. The quantity of air supplied being regulated by a camper device 67 to pro-vide sufficient air to transport the secondary fuel. The coal to be burned in the furnace 14 is delivered in raw form via pipe 58 from the raw coal storage bun~er 60 to the pulverizer feeder 62, which regulates the quantity of coal supplied to the pulverizer 56 in response to the load demand on thelvap~r generator 10 in a manner well known in the art. The pulverizer-56, being of the air-swept type, is supplied with pressurized combustion and transport air from a primary air fan 52, the quantity of air supplied being regulated by a damper device 68 to provide sufficient air to initiate ignition at tha burner discharge and provide adequate 1OW velocity $o insure a thorough sweeping of the pulverizer 56, coal burner pipe 64 ... . .. ...... ......... . ..... . . ~ .. .. ~ . . . ~ . .
~2~
and the central annular passage~ay 98.
The aiT required for combustion is delivered to the vapor generator by a forced draft fan 32 including a damper de~ice 66 which regulates the quantity of air in response to the load demand on the vapor generator 10 in a manne~ well known in the art. The combustion air is heated as it comes into indirect con~act with the flue gases flowing through the tubes of an air heater 28 and is thereater conveyed through a duct 36 to be apportioned between branch ducts 40 and 38, the former leads to the pul~erizer 56 as aforedescribed and the latter leads to the windbox whence the air is apportioned between the central passageway 94 via duct 65 and 71, the inner annular passageway 72, and the outer annula~ passageway 74.
From the foregoing, it will be noted that four separate flow paths are provided for admit-ting combustion air to the burner port 50; the central passageway 94, the central annular passageway 98, the inner annular passageway 72, and the outer annular passageway 74. The design of these flow paths and the regulation of the proportional amounts of air passing through these flow paths coupled with the enhancement of fuel-air dis-tribution and the shaping o~ the fuel discharge pattern consti-tute major features of the p~esent invention.
Under actual operation, it has been found that maintaining combustion air which flows through the central passageway 94 within a range of 5 to lO percent of stoichiometric air, that which flows through the central annular passageway 98 within - a range of 15 to 30 percent of stoichiometric air, and that which flows through the inner-annular passageway 72 within a range of 22 to 35 percent of stoichiometric air creates a stable,,igni-tion zone under a reducing atmosphere and pro~ides lower peak flame temperature. The combustion air whicn flows through the outer annular passageway 74 represents the air needed to complete the combustion of the fuel.
l~hile in accordance with the provlsions of the statutes 35 ~ there is illustrated and described herein a specific embodiment of the in~ention, those skilled in the art will understand that ....... ................. ........... , ... ... ,,.,,.,,,",.. ~.;
~, ~ 4~
cnanges may be made in the form of the inven~ion covered by the claims, and that certain features of the invention may sometimes be uced to advantage without a corresponding use o the other features.
., , i,
Claims (2)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A multi-fuel burning apparatus comprising:
a first tubular conduit, defining a central passageway, opening in a burner port for discharge and combustion of fuel in a combustion chamber, means for supplying an air-conveyed solid carbonaceous fuel to the first tubular conduit for discharge and combustion in the combustion chamber, a liquid fuel assembly centrally extending within the first tubular conduit for discharge and combustion of a liquid fuel in the combustion chamber, a second tubular conduit concentrically disposed about the first tubular conduit and defining a central annular passageway for discharge and combustion of fuel in the combustion chamber, means for supplying air-conveyed pulverized coal to the central annular passageway, a first sleeve member having a portion thereof concentrically spaced about the second tubular conduit to form an inner annular passageway for delivery and supply of combustion air to the combustion chamber, a second sleeve member having a portion thereof concentrically spaced about the first sleeve member to form an outer annular passageway for delivery and supply of additional combustion air to the combustion chamber, means for separately controlling the combustion air such that 5 to 10 percent of stoichiometric air is delivered to the central passageway, 15 to 30 percent to the central annular passageway, 22 to 35 percent to the inner annular passageway, and the remaining combustion air for complete combustion to the outer annular passageway for low NOx production.
a first tubular conduit, defining a central passageway, opening in a burner port for discharge and combustion of fuel in a combustion chamber, means for supplying an air-conveyed solid carbonaceous fuel to the first tubular conduit for discharge and combustion in the combustion chamber, a liquid fuel assembly centrally extending within the first tubular conduit for discharge and combustion of a liquid fuel in the combustion chamber, a second tubular conduit concentrically disposed about the first tubular conduit and defining a central annular passageway for discharge and combustion of fuel in the combustion chamber, means for supplying air-conveyed pulverized coal to the central annular passageway, a first sleeve member having a portion thereof concentrically spaced about the second tubular conduit to form an inner annular passageway for delivery and supply of combustion air to the combustion chamber, a second sleeve member having a portion thereof concentrically spaced about the first sleeve member to form an outer annular passageway for delivery and supply of additional combustion air to the combustion chamber, means for separately controlling the combustion air such that 5 to 10 percent of stoichiometric air is delivered to the central passageway, 15 to 30 percent to the central annular passageway, 22 to 35 percent to the inner annular passageway, and the remaining combustion air for complete combustion to the outer annular passageway for low NOx production.
2. The multi-fuel burning apparatus of Claim 1 wherein any combination of fuels can be burned simultaneously.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US25183781A | 1981-04-08 | 1981-04-08 | |
| US251,837 | 1981-04-08 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1204999A true CA1204999A (en) | 1986-05-27 |
Family
ID=22953621
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000394058A Expired CA1204999A (en) | 1981-04-08 | 1982-01-13 | Low nox multifuel burner |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0062228B1 (en) |
| CA (1) | CA1204999A (en) |
| DE (1) | DE3205640A1 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4902221A (en) * | 1987-05-12 | 1990-02-20 | Control Systems Company | Burner assembly for coal fired furnaces |
| DE3825291A1 (en) * | 1988-07-26 | 1990-02-01 | Ver Kesselwerke Ag | METHOD AND COMBUSTION PLANT FOR COMBUSTION OF FOSSILER FUELS WITH REDUCED EMISSIONS OF NITROGEN |
| DE3933050C2 (en) * | 1989-10-04 | 2000-06-15 | Pillard Feuerungen Gmbh | Method for operating a burner for rotary kilns and burners therefor |
| CN108916876A (en) * | 2018-07-05 | 2018-11-30 | 南京锐控机电制造有限公司 | Gas source automatic identification control device and gas source automatic identifying method |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE349608C (en) * | 1918-12-29 | 1922-03-04 | Wilhelm Lautenschlaeger | Dust and liquid fuel burners |
| CH429002A (en) * | 1963-02-24 | 1967-01-31 | Ghelfi Salvatore | Burner for the combustion of either one or several injectable fuels |
| US3788796A (en) * | 1973-05-09 | 1974-01-29 | Babcock & Wilcox Co | Fuel burner |
| US3904349A (en) * | 1974-05-22 | 1975-09-09 | Babcock & Wilcox Co | Fuel burner |
| BE843283A (en) * | 1976-06-23 | 1976-10-18 | BURNER | |
| US4162140A (en) * | 1977-09-26 | 1979-07-24 | John Zink Company | NOx abatement in burning of gaseous or liquid fuels |
| DE3105540A1 (en) * | 1981-02-16 | 1982-09-02 | Steag Ag, 4300 Essen | METHOD FOR IGNITIONING A DUST POWER BURNER DESIGNED AS A CIRCULAR BURNER WITH A CENTRAL DUST BURNER ARRANGED IN THE POWER BURNER WITH PNEUMATIC HOLDING OF THE IGNITION FLAME AND BURNER ARRANGEMENT FOR CARRYING OUT THE PROCEDURE |
-
1982
- 1982-01-13 CA CA000394058A patent/CA1204999A/en not_active Expired
- 1982-02-17 DE DE19823205640 patent/DE3205640A1/en active Granted
- 1982-03-23 EP EP19820102393 patent/EP0062228B1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| EP0062228A1 (en) | 1982-10-13 |
| DE3205640C2 (en) | 1990-02-08 |
| DE3205640A1 (en) | 1983-02-24 |
| EP0062228B1 (en) | 1985-06-26 |
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