Abb Research Ltd.

Asea Brown Boveri Inc.

Abb Management Ag

Asea Brown Boveri Ag

Abb Alstom Power (switzerland) Ltd.

Abb Alstom Power (switzereland) Ltd

Hans Peter Knopfel

Klaus Dobbeling

Thomas Ruck

Thomas Sattelmayer

Wolfgang Polifke

Jurgen Haumann

Adnan Eroglu

Peter Senior

Claude Pelet

Hans Peter

Timothy Albert Griffin

Dieter Winkler

Christian Steinbach

Bettina Paikert

Peter Jansohn

Giacomo Bolis

Emil Kuhn

Thomas Sattelamayer

Donald Frank Walker

Thomas Sattlemayer

In a burner for operating a heat generator, which burner essentially comprises a swirl generator (100), a transition piece (200) arranged downstream of the swirl generator, and a mixing tube (20), transition piece (200) and mixing tube (20) form the mixing section of the burner, this mixing section being arranged upstream of a combustion space (30). In the region of the tangential combustion-air-directing inflow ducts (101b-104b), fuel-directing ducts (121-124), the cross section of flow of which is designed for a low-calorific fuel (116), extend along the swirl generator (100). The fuel-directing ducts (121-124) end at a distance upstream of the transition of the tangential inflow ducts (101b-104b) into an interior space of the swirl generator (100), whereby partial mixing between the two media (115, 117) takes place before the mixture flows into the interior space (118). In addition, this setting-back provides sufficient space for other fuel-directing lines (111-114) in this region.

Burner for operating a heat generator

In a premix burner, the swirl-stabilized interior space (18) has a conical inner body (13) running in the direction of flow. The outer casing of the interior space (18) is pierced by tangentially arranged air-inlet ducts (11a, 12a) through which a combustion-air flow (16) flows into the interior space (18). The swirl flow (23) forming in the interior space (18) is enriched with a fuel via at least one fuel lance (17). The mixture of the two media is then formed in the downstream mixing tube (21). The mixing tube (21) then merges into a combustion space (31) via a jump in cross section, a backflow zone (32) forming in the region of the plane of the jump in cross section, which backflow zone (32) ensures the stability of the combustion.

Premix burner

A burner for operating a heat generator, the burner including a swirl generator for a combustion-air flow and a mechanism for injecting at least one fuel into the combustion-air flow, a mixing section arranged downstream of the swirl generator and having a number of transition passages for passing a flow formed in the swirl generator into a mixing tube arranged downstream of the transition passages. The combustion-air flow into the swirl generator flows against turbulence generators, which are located upstream of the injection of the fuel into the combustion-air flow, and the turbulence generators include individual bars set transversely to the combustion-air flow.

In a burner for operating a combustion chamber, which burner essentially comprises a swirl generator (100), a transition piece (200) arranged downstream of the swirl generator, and a mixing tube (20), transition piece (200) and mixing tube (20) forming the mixing section of the burner and being arranged upstream of a combustion space (30). The swirl generator (100) itself comprises at least two hollow, conical sectional bodies (140, 141, 142, 143) which are nested one inside the other in the direction of flow, the respective center axes of these sectional bodies running mutually offset in such a way that the adjacent walls of the sectional bodies form inlet ducts (120), tangential in their longitudinal extent, for a combustion-air flow (115). In the region where the combustion-air flow (115) flows into the swirl generator (100), fuel injectors (116, 116a) are arranged on both sides along the inflow edges, which fuel injectors act offset with respect to one another, in such a way that the inflow cross section of the duct (120) is integrally covered with fuel, with the result that a maximized premixing is achieved.

In a burner for operating a combustion chamber, which burner essentially comprises a swirl generator (100), a transition piece (200) arranged downstream of the swirl generator, and a mixing tube (20), transition piece (200) and mixing tube (20) forming the mixing section of the burner and being arranged upstream of a combustion space (30), there are means (302, 303, 304) in the lower region of the mixing tube (20) which bring about cooling of the base plate (305) forming a front wall. The air quantity (307) used here is passed into the flow (40) of the mixing tube (20). A leaner mixing and lower NOx emissions are thereby achieved.

When a boiler plant (100), which is equipped with an air plenum (104), is in operation, during the startup phase the admission pressure in this air plenum (104) is lowered in terms of time and amount via a blowoff device (106) with respect to combustion air (7) and startup air (105) made available from this air plenum (104). The air coefficient to the burner is consequently reduced. This ensures that, by means of such a near-stoichiometric fuel/air mixture, favorable ignition conditions are provided in the burner and the pollutant emissions during the startup phase are greatly reduced.

Method for operating a boiler plant

In a boiler plant for heat generation, which consists essentially of a combustion space and of a burner acting on the head side of the combustion space, this combustion space is divided into two parts (17,102a) by the insertion of an annular disk (103). A limited internal backflow zone (24) forms in the front part (17) in interaction with this disk (103). This disk (103) then causes external backflow zones (106) fed by recirculated flue gases (30) to form within the front part (17) of the combustion space, the flue gases of said external backflow zones being introduced into the combustion process of the burner, said backflow zones (24, 106) being in each case separated locally from one another. Better flame stabilization, lower pulsations and markedly lower pollutant emissions can thereby be achieved when the burner is operating.

Boiler plant for heat generation

In a method of operating a swirl-stabilized burner operated with gaseous and/or liquid fuels (12, 16), in which combustion air (7) or a mixture of recycled flue gas (30) and fresh air (29), which mixture is formed by injector delivery, and fuel (12, 16) are intensively mixed by means of a swirl generator (37) and then burned, in the course of which a backflow zone (24), which stabilizes the flame, is formed, starting air (38), which has at least a radial velocity component, is injected during the starting action at the downstream end of the swirl generator (37) in such a way as to be directed from the margin of the burner into the center. The injection of the starting air (38) is switched off after the end of the starting action, so that the burner works in such a way as to be unaffected in normal operation. The invention improves the ignition conditions, increases the flame stabilization, and reduces the pollutant emissions when the burner is being started.

Method of operating a swirl stabilized burner and burner for carrying

In a burner for operating a combustion chamber, which burner essentially comprises a swirl generator (100) and a mixing section (220) arranged downstream of the swirl generator, this mixing section acting upstream of a combustion chamber (30), the swirl flow induced by the swirl generator (100) is directed via transition passages (201) into the mixing section (220). At the outlet of a mixing tube (20) belonging to the mixing section (220), the burner front (70) of the mixing tube (20) is provided with at least one torus-like notch (71) on the combustion-chamber side. Thus the stability of the backflow zone (50) can be intensified, which has a positive effect on the combustion from all aspects.

Burner for operating a combustion chamber

A burner for operating a combustion chamber, which burner essentially comprises a swirl generator (100), a transition piece (200) arranged downstream of the swirl generator, and a mixing tube (20), transition piece (200) and mixing tube (20) forming the mixing section of the burner and being arranged upstream of a combustion space (30). At the end of the mixing tube (20) in its region leading out to a downstream combustion space (30), the mixing tube (20) has a first radius (R.sub.1) which runs convexly relative to the burner axis (60). This radius (R.sub.1) merges into a second radius (R.sub.2) which extends up to the outlet plane (70) of the mixing tube (20) and runs concavely relative to the burner axis (60), the covered sector (.beta..sub.1 +.beta..sub.2) of the two radii (R.sub.1, R.sub.2) being 90.degree. at most. With this configuration, enlargement and stabilization of the backflow zone (50) as well as axial orientation of the marginal flow are achieved.

In a burner for operating a combustion chamber, which burner essentially comprises a swirl generator (100), a transition piece (200) arranged downstream of the swirl generator, and a mixing tube (20), transition piece (200) and mixing tube (20) forming the mixing section of the burner and being arranged upstream of a combustion space (30), a pilot-burner system (300) is arranged in the lower region of the mixing tube (20), which pilot-burner system (300), at minimized pollutant emissions, stabilizes the flame front, in particular in the transient load ranges.

A pressure atomizer nozzle comprises a nozzle body (30) in which is formed a turbulence and/or swirl chamber (39) and having a nozzle bore (33). At least one first feed channel (41, 41a) for the liquid (37) to be atomized connects to the chamber as a first feed stage for feeding said liquid (37) under pressure. At least one second feed channel (38) connects to the chamber as a second feed stage for feeding part of the liquid (37) to be atomized or for feeding a second liquid (37') to be atomized. The second feed channel feeds liquid into the chamber under pressure and with a swirl. The two stage pressure atomizer nozzle allows, for example, simple adaptation of the fuel spray cone angle to the respective operating conditions of a gas turbine burner.

Pressure atomizer nozzle

In a burner of the double-cone design for burning liquid (12) and gaseous fuels (16), the at least two sectional cone bodies (1, 2) overlap at least partly, the overlap angle (.delta.) increasing in the direction of flow of the burner, and the distance between the fuel injectors (15) and the air-inlet plane (21) into the burner increasing simultaneously with the increase in the overlap angle (.delta.). As a result, the air-inlet plane (21) and the fuel-injection plane (22) no longer coincide. Improved premixing of the gaseous fuel (16) with the combustion air is achieved by the invention, which leads to lower NOx emissions of the burner and to lower thermal loading of the burner front.

Burner

In a combustion chamber of a gas-turbine group which essentially comprises a mixing section (2) for premixing an air/fuel mixture (16) and a downstream combustion space (3), a jump (5) in cross section is provided at the transition between the two said flow sections (2/3). This jump (5) in cross section induces the cross section of flow of the combustion space (3) and at the same time forms outer recirculation zones (10) in the combustion space (3). Flow passages (4) branch off in the end phase of the mixing section (2), which flow passages (4) then lead into the outer recirculation zones (10). A portion (9) of the air/fuel mixture flows out of the mixing section (2) through these flow passages (4) and into the outer recirculation zones (10), the portion being enriched here with an additional fuel (6). This fuel (6) is introduced via a circular line (19) provided with bores (18). The branched off mixture (9) constitutes a self-igniting pilot flame in the outer recirculation zones (10), which pilot flame substantially stabilizes the flame front (20).

Combustion chamber

In a burner for a heat generator, which consists essentially of a swirl generator (100a) for a combustion air stream (115) and of means for injecting a fuel into this combustion air stream, a mixing stage (220) is arranged downstream of said swirl generator. This mixing stage has, within a first stage part (200), a number of transition channels (201) running in the direction of flow, which ensure the continuous transfer of the flow (40), formed in the swirl generator (100a), into a tube (20) located downstream. A nozzle (103), arranged on the head side and on the burner axis (60), for the injection of a fuel is offset upstream at a distance relative to the start of the swirl generator.

Growing community of inventors

Besenburen, Switzerland

Hans Peter Knopfel