U.S. patent application number 15/030916 was filed with the patent office on 2016-09-01 for gas turbine burner hub with pilot burner.
This patent application is currently assigned to Siemens Aktiengesellschaft. The applicant listed for this patent is SIEMENS AKTIENGESELLSCHAFT. Invention is credited to Andreas Bottcher, Tobias Krieger, Patrick Lapp, Andreas Mann, Stefan Reich, Kai-Uwe Schildmacher, Sascha Staring, Daniel Vogtmann.
Application Number | 20160252254 15/030916 |
Document ID | / |
Family ID | 51866131 |
Filed Date | 2016-09-01 |
United States Patent
Application |
20160252254 |
Kind Code |
A1 |
Bottcher; Andreas ; et
al. |
September 1, 2016 |
GAS TURBINE BURNER HUB WITH PILOT BURNER
Abstract
A burner arrangement for a combustion chamber for combustion of
fluid fuels has a main burner and pilot burner arranged centrally
within the main burner for the ignition and/or stabilization of the
combustion of the main burner. The main burner has central fuel
feed arrangement arranged around the pilot burner, an annular air
duct surrounding the central fuel feed arrangement for the supply
of combustion air, first fuel nozzles for injection of
substantially gaseous fuel into the annular air duct. The first
fuel nozzles are fed from a first fuel distributor in the central
fuel feed arrangement, and second fuel nozzles for the injection of
a substantially liquid fuel into the annular air duct are fed from
a second fuel distributor in the central fuel feed arrangement.
Ducts are provided which branch off from at least one of the fuel
distributors and issue into the pilot burner.
Inventors: |
Bottcher; Andreas;
(Mettmann, DE) ; Krieger; Tobias; (Oberhausen,
DE) ; Lapp; Patrick; (Berlin, DE) ; Mann;
Andreas; (Stendal, DE) ; Reich; Stefan;
(Dusseldorf, DE) ; Schildmacher; Kai-Uwe; (Mulheim
a.d. Ruhr, DE) ; Staring; Sascha; (Duisburg, DE)
; Vogtmann; Daniel; (Dusseldorf, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SIEMENS AKTIENGESELLSCHAFT |
Munchen |
|
DE |
|
|
Assignee: |
Siemens Aktiengesellschaft
Munich
DE
|
Family ID: |
51866131 |
Appl. No.: |
15/030916 |
Filed: |
October 23, 2014 |
PCT Filed: |
October 23, 2014 |
PCT NO: |
PCT/EP2014/072741 |
371 Date: |
April 21, 2016 |
Current U.S.
Class: |
60/39.463 |
Current CPC
Class: |
F23R 3/286 20130101;
F23R 3/36 20130101; F23D 2900/00008 20130101; F23R 3/343
20130101 |
International
Class: |
F23R 3/34 20060101
F23R003/34; F23R 3/36 20060101 F23R003/36; F23R 3/28 20060101
F23R003/28 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 31, 2013 |
DE |
10 2013 222 152.5 |
Claims
1. A burner arrangement for a combustion chamber for burning fluid
fuels, comprising: a main burner and a pilot burner arranged
centrally therein, which pilot burner serves to ignite and/or to
stabilize main burner combustion, the main burner comprising a
central fuel feed arrangement arranged around the pilot burner, an
annular air duct surrounding the central fuel feed arrangement for
supplying combustion air, first fuel nozzles for injecting a
substantially gaseous fuel into the annular air duct, wherein the
first fuel nozzles are supplied by a first fuel manifold in the
central fuel feed arrangement, and second fuel nozzles for
injecting a substantially liquid fuel into the annular air duct,
wherein the second fuel nozzles are supplied by a second fuel
manifold in the central fuel feed arrangement, wherein ducts are
provided which branch off from at least one of fuel manifolds and
lead into the pilot burner and the pilot burner has a gas feed duct
independent of the ducts.
2. The burner arrangement as claimed in claim 1, wherein the pilot
burner comprises a pilot annular air duct which supplies combustion
air and the ducts lead into this pilot annular air duct.
3. The burner arrangement as claimed in claim 2, wherein the ducts
leading into the pilot annular air duct are uniformly distributed
around the circumference thereof.
4. The burner arrangement as claimed in claim 1, wherein the ducts
take the form of bores.
5. The burner arrangement as claimed in claim 1, wherein the ducts
branch off from the second fuel manifold and have nozzles at their
ends leading into the pilot burner.
6. The burner arrangement as claimed in claim 5, wherein the
nozzles are cavitation-free and screw-fastenable.
7. The burner arrangement as claimed in claim 1, wherein the
annular air duct comprises swirl vanes and the first fuel nozzles
are arranged in these swirl vanes.
8. The burner arrangement as claimed in claim 1, wherein the pilot
burner comprises an oil feed duct independent of the ducts.
9. The burner arrangement as claimed in claim 1, wherein the
combustion chamber comprises a gas turbine combustion chamber,
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the US National Stage of International
Application No. PCT/EP2014/072741 filed Oct. 23, 2014, and claims
the benefit thereof. The International Application claims the
benefit of German Application No. DE 102013222152.5 filed Oct. 31,
2013. All of the applications are incorporated by reference herein
in their entirety.
FIELD OF INVENTION
[0002] The invention relates to a burner arrangement, in particular
a burner arrangement with a main burner and a pilot burner, and to
the mixing of fuel with air.
BACKGROUND OF INVENTION
[0003] When operating a gas turbine plant, the mixing of fuel with
air is of crucial significance, if optimum and consequently
low-pollutant combustion is to be achieved. For this purpose, fuel
is injected in a maximally precisely metered manner and fed to the
combustion air. To achieve good mixing of the fluids, both the
combustion air and the fuel are set in swirling motion by
structural measures. This is typically mainly achieved by curved
vanes and fuel nozzles.
[0004] The increasingly stringent stipulations relating to
pollutant reduction require constant improvement of combustion.
Pollutants such as nitrogen oxides (NO.sub.x) are mainly influenced
by the mixing ratio of fuel to air and the efficiency of
combustion. Complete combustion of the fuel is desirable if
pollutants are to be reduced.
[0005] Possible fuels are gaseous fuels, such as natural gas or
synthesis gas, and also liquid fuels. It is precisely in the case
of the liquid fuel oil that nozzle geometry in combination with
vane swirl has hitherto primarily influenced mixing of said fuel
with air. No further active influencing of for example the depth of
penetration of the fuel into the air stream or the swirling of the
fuel and thus optimized mixing does not conventionally take
place.
[0006] In the case of gas premixing injection, the gas is injected
for example via bores in a swirl vane and premixed and swirled with
the compressed air.
[0007] With both fuels, gas and oil, a pilot burner is typically
used to stabilize the premixing flame. In the case of oil, this is
an oil diffusion burner, while in the case of gas it is a pilot gas
burner.
SUMMARY OF INVENTION
[0008] An object of the invention is to further develop the
above-stated device such that, when the device is in operation,
maximally complete combustion is achieved.
[0009] According to aspects of the invention, this object is
achieved by the burner arrangement according to the independent
claim. Advantageous further developments of the invention are
defined in the dependent claims. In a burner arrangement for a
combustion chamber, in particular a gas turbine combustion chamber,
for burning fluid fuels, with a main burner and a pilot burner
arranged centrally therein, which pilot burner serves to ignite
and/or to stabilize main burner combustion, the main burner
comprising a central fuel feed arrangement arranged around the
pilot burner, an annular air duct surrounding the central fuel feed
arrangement for supplying combustion air, first fuel nozzles for
injecting a substantially gaseous fuel into the annular air duct,
wherein the first fuel nozzles are supplied by a first fuel
manifold in the central fuel feed arrangement, and second fuel
nozzles for injecting a substantially liquid fuel into the annular
air duct, wherein the second fuel nozzles are supplied by a second
fuel manifold in the central fuel feed arrangement, ducts are
provided which branch off from at least one of the fuel manifolds
and lead into the pilot burner and the pilot burner has a gas feed
duct independent of the ducts, thereby ensuring that the pilot
flame is enhanced as a result of removal from the premixing passage
of the diagonal swirler in the main burner and addition to the
pilot burner, whereby combustion is improved and the emissions
therefrom are reduced.
[0010] In this case, it is convenient if the pilot burner comprises
a pilot annular air duct for supplying combustion air and the ducts
lead into this pilot annular air duct.
[0011] To be able to supply the fuel as uniformly as possible to
the pilot annular air duct, it is advantageous for the ducts
leading into the pilot annular air duct to be uniformly distributed
around the circumference thereof.
[0012] In this respect it is convenient, because it is simple and
inexpensive to implement, for the ducts to take the form of
bores.
[0013] In one advantageous embodiment, the ducts branch off from
the second fuel manifold and comprise nozzles at their ends leading
into the pilot burner. The second fuel manifold for injecting a
substantially liquid fuel, i.e. oil, is mechanically particularly
stressed, such that it is particularly advantageous here for the
nozzles to be cavitation-free and screw-fastenable should
replacement be required.
[0014] With regard to the best possible intermixing of fuel and
air, it is advantageous for the annular air duct to comprise swirl
vanes and for the first fuel nozzles to be arranged in these swirl
vanes.
[0015] The admixture of fuel from the central fuel feed arrangement
does not however replace the independent supply of gas or oil in
the pilot burner, but rather in combination therewith ensures
additional fuel enrichment, for which reason in advantageous
embodiments the pilot burner also comprises an oil feed duct
independent of the ducts, in addition to a gas feed duct
independent of the ducts.
[0016] The additional mass flows according to the invention from
the gas or oil manifolds are mixed with the compressed air in the
pilot gas line and then combined with the fuel in the pilot burner.
This makes possible additional fuel enrichment and mixing, which
may lead to an improvement in the fuel/air mixture and thus to a
reduction in pollutants.
[0017] The invention may also be implemented in an existing design
by the simple introduction of bores and/or nozzles.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The FIGURE shows schematically, and not to scale, a burner
arrangement according to the invention.
DETAILED DESCRIPTION OF INVENTION
[0019] The invention is described in greater detail below with
reference to a drawing. The FIGURE shows schematically, and not to
scale, a burner arrangement 1 according to the invention, which may
optionally be used in conjunction with a plurality of similar
burner arrangements for example in the combustion chamber of a gas
turbine plant. The burner arrangement 1 has a main axis 19 and
comprises a pilot burner 3 and a main burner 2 concentrically
surrounding the pilot burner 3. Both pilot burner 3 and main burner
2 may optionally be operated with gaseous and/or liquid fuels, such
as for example natural gas or heating oil. The pilot burner 3 then
comprises as fuel ducts an inner oil feed duct 18 and an inner,
annular gas feed duct 17 concentrically surrounding said duct 18.
This is in turn surrounded concentrically by a pilot annular air
duct 13 for supplying combustion air 14.
[0020] In or on this pilot annular air duct 13 it is additionally
possible to arrange a suitable ignition system (not shown in the
FIGURE).
[0021] In the pilot annular air duct 13 there are additionally
arranged swirl vanes 20, which comprise fuel nozzles 21 for
supplying a fuel to a stream 14 of oxygen-containing gas, typically
air.
[0022] The main burner 2 surrounding the pilot burner 3 comprises,
relative to the main axis 19, a radially outer annular air duct 5
for the combustion air 6, through which extend a plurality of swirl
vanes 16 of a swirl vane assembly. These swirl vanes 16 have as
inlet for fuel first fuel nozzles 7, through which fuel gas may be
injected into the air 6 flowing in through the annular air duct 5.
The first fuel nozzles 7 are supplied via a first fuel manifold 8
in a central fuel feed arrangement 4. A second fuel manifold 10 in
the central fuel feed arrangement 4 supplies second fuel nozzles 9
typically with oil.
[0023] The task of the pilot burner 3 is to maintain stable
combustion operation in the burner arrangement 1, since this is
mostly operated with a lean mixture with a tendency towards
instability.
[0024] In the example in the FIGURE, the invention provides not
only ducts 11 which branch off from the first fuel manifold 8 for
the gas supply and lead into the pilot burner 3 but also ducts 12
which branch off from a second fuel manifold 10 for oil. The ducts
12 have nozzles 15 at their ends leading into the pilot burner
3.
[0025] The ducts 11, 12 are distributed uniformly over the
circumference of the pilot annular air duct 13 and may take the
form of simple bores.
* * * * *