Patent Application
20080280241
This application claims the benefits of German application No. 10 2007 021 926.3 filed May 10, 2007 and is incorporated by reference herein in its entirety.
The subject matter of the application relates to an oil/slurry burner with injection atomization for the gasification of solids-containing liquid fuels, a method for operating an oil/slurry burner and a method for starting up an oil/slurry burner.
The invention relates to an oil/slurry burner with injection atomization which is used for the steam-oxygen gasification of solids-containing liquid fuels (slurries or similar liquid fuels) under high pressures of e.g. 80 bar (8 MPa) and temperatures of e.g. 1200 to 1900° C. in reactors with liquid slag removal.
Oil/slurry burners with injection atomization for partial oxidation of liquid fuels, comprising a cylindrical water-cooled housing and an internal liquid feed around which the atomizing agent and oxidant are supplied in coaxially disposed annuli, are well-known.
Said burners are started up either by a gas/air operated pilot burner disposed adjacent to the oil/slurry burner and equipped with an ionization flame monitoring device and ignition device, or, in the case of ceramic-lined reactors, by a separate heating burner which first brings to temperature the brickwork on which the oil/slurry burner is subsequently ignited.
The known burner has the following disadvantages:
Due to a centralized supply of liquid, use of the burner is restricted to a single fuel.
To start up the burner, another burner is required as a heating burner which is subsequently replaced, or a pilot burner disposed laterally adjacent to the oil/slurry burner must be present, in which case reliable lateral cross-ignition to the oil/slurry burner is questionable.
Startup of the oil/slurry burner takes place basically pressurelessly and under oxidizing atmosphere and must initially be carried over slowly to the reducing reactor atmosphere by means of complicated media adjustments before the actual gasification process can commence.
If after the heating process the brickwork temperature falls below the specified brickwork ignition temperature due to delay in the oil/slurry burner installation, the entire heating process must be repeated.
Such typical solutions are described in patent U.S. Pat. Nos. 151,020 and 214,911.
The object of the invention is to create an oil/slurry burner with injection atomization which operates reliably at pressure under the conditions of steam-oxygen gasification of solids-containing liquid fuels. It is aimed by means of constructional measures to implement an oil/slurry burner with injection atomization which compensates for the abovementioned disadvantages of pressurized gasification of solids-containing liquid fuels and ensures reliable operation with even flame spread.
This object is achieved in respect of a subject matter outlined by the features of the preamble by the features of the characterizing portion of the claims.
Advantageous developments of the subject matter of the application are set forth in the dependent claims.
The subject matter of the application will now be explained in greater detail as an exemplary embodiment to the extent required for understanding and with reference to the accompanying drawings, in which:
In the figures, the same reference symbols are used to denote identical elements.
The inventive oil/slurry burner with injection atomization comprises a centrally disposed pilot burner section 1 with fuel gas and oxidant supply, a flame monitoring device and an electrical high-voltage ignition device. Disposed around said module is an annulus 2 for supplying the oxidant for the oil/slurry burner section. Swirl blades 3 for swirling the oxygen stream are disposed at the annular outlet port.
Both modules (pilot burner section and oxidant supply) are incorporated in another module, the burner holder 7. The entire burner holder module is implemented with a water cooling system in the form of a coiled tube in order to dissipate the heat acting on said module. In addition, the modules disposed in the center of the burner holder, the pilot burner section and additional oxidant supply, are also equipped with separate water cooling systems.
According to the invention provision is made for the liquid fuel and atomizing agent (steam or similar) to be supplied in such a way that a plurality (n=2, 3 . . . ) of straight fuel/steam feeding elements are disposed between the housing wall of the burner holder and the central oxidant supply. Said feeding elements are intrinsically straight and inclined to the burner axis and end at the burner mouth adjacent to the oxidant outlet in the form of an oil/atomizing agent nozzle. The atomizing agent (steam or similar) causes the solids-containing liquid fuel to be finely atomized before it comes into contact with the oxidant.
By implementing the oxidant supply using swirl blades, strong rotation is imparted to the discharging oxygen stream into which the atomized liquid jets discharging via the feeding elements are sucked.
At the outlet of the media the individual streams are mixed to produce a single rotating liquid/steam/oxygen stream. This ensures an even flame spread and stabilization.
At the same time the width and length of the flame spread can be influenced using different settings of the swirl blades.
By introducing the liquid fuel and atomizing agent in individual completely implemented tubes with a corresponding nozzle, different liquid fuels can be supplied simultaneously via the individual feeds and converted in a flame reaction.
The oil/slurry burner with injection atomization is started up by means of the integral pilot burner under reducing conditions and at reactor system operating pressure. The pilot burner is ignited at slight reactor pressure (2-5 bar) and likewise under reducing reaction chamber conditions.
The invention comprises an oil/slurry burner with injection atomization for the gasification of solids-containing liquid fuels (slurries or similar liquid fuels) under high pressures and temperatures in reactors with liquid slag removal for steam-oxygen gasification, having a cooled housing (7) for accommodating a centrally disposed pilot burner (1) used for starting up the oil/slurry burner unit and having a gas and oxidant supply as well as an integrated flame monitoring device and high-voltage ignition device, an annular duct (2) disposed around said pilot burner (1) for supplying the oxidant, and straight feeding elements (4 and 5) inclined to the burner axis for introducing liquid fuel and atomizing agent, characterized in that a plurality of feeding elements (4 and 5) are present and said feeding elements (4 and 5) are intrinsically straight and inclined to the burner axis and end at the outlet directly adjacent to the annular oxidant supply duct (2) in a nozzle (6) at whose outlet swirl devices (3) are provided which impart a strong rotating motion to the oxidant stream (2), thereby allowing the flame geometry to be influenced by suitable configuration.
The invention is also characterized in that, by means of the arrangement of a plurality of feeding elements (4 and 5), different liquid fuels can be introduced which end in a common flame and which are started up under reducing conditions and at reactor operating pressure by a pilot burner incorporated in the center.
The invention also relates to a method wherein a pilot burner incorporated in the center of the burner unit is ignited under reducing reactor atmosphere and at slightly elevated system pressure and then, as the pilot burner output increases, the reaction chamber pressure is raised to the operating pressure necessary for igniting the oil/slurry burner.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2007 021 926.3 | May 2007 | DE | national |
