DE202007018472U1 - Premixing gas burner - Google Patents

Abstract

premixing Gas burner with a cylindrical fuel element with an inlet opening for a gas / air mixture at one end and with cooling channels in the area below a burner surface, characterized in that that the cylindrical fuel assembly of several in the axial direction lined up, mutually spaced slats (1) formed which radially outwardly extending flow channels (3) for the gas / air mixture form.

Description

The Innovation relates to a premixing gas burner with a cylindrical Fuel element according to the preamble of the protection claim 1.

Such premixing gas burners are used as area burners for atmospherically fired heaters, for example from the DE 196 41 040 A1 known. In this case, many individual, parallel, lamellar sheets are fixed to a serpentine winding pipe, which serves as a cooling medium through which the heating medium flows. The distance between the individual lamellae results in parallel flow openings for the fuel gas or for a gas / air mixture, which then exits and burns on a burner surface.

A premixing gas burner with a cylindrical fuel element is in the DE 38 31 624 A1 shown and described. In such a gas burner, the cylindrical fuel element is exposed to very high temperatures, since the flames are close to the surface. Within this outer cylinder, which serves as a burner surface and therefore has a very fine perforation, further cylinders are arranged for uniform distribution of the gas / air mixture on the surface and for acoustic decoupling of combustion chamber and mixture space. These serve as throttling and distribution cylinders, are concentric with the outer cylinder, usually have slightly larger flow openings for the gas / air mixture than the outer cylinder and are fastened together with this on the upstream end element.

Of the Innovation is therefore the basis of the task, in a premixing Gas burners the combustion quality and robustness, especially with regard to changing gas mixture compositions and changing flow rates, to optimize.

Innovation was this is achieved with the features of the protection claim 1. Advantageous developments are to be taken from the subclaims.

Of the Pre-mixing gas burner is characterized in that the cylindrical Fuel assembly of several in the axial direction lined up, is formed spaced apart slats, which radially to outside running flow channels for form the gas / air mixture. Here are the spaced apart Slats of the cylindrical fuel assembly to the cooling channels fixed. Pass through at least four cooling channels therefore in the axial direction of the fuel assembly.

The the fuel element by cross-cooling channels at least in pairs with each other on at least one end face coupled, so that in the axial direction at least one flow line and a return line for the cooling medium is trained. Preferably, therefore, the cooling channels tubular and approximately in the middle the radially extending flow channels for the gas / air mixture and symmetrical to the center of the fuel assembly arranged.

At the inlet opening for a gas / air mixture opposite end face is the fuel element with closed a disc-like cover. Furthermore, at this Front side inside the fuel assembly a conical displacement body is attached, the tip of the inlet opening shows. The conical displacement body is preferably on the disc-like cover of the fuel assembly fixed and extends about half the length of the fuel element.

The mutually spaced lamellae of the cylindrical fuel assembly have the same or the same length over its length different inside diameter, in order for a uniform Distribution of the gas / air mixture to ensure. Alternative or supplementary This can also be the distances between the individual Slats of the cylindrical fuel element over its length be the same or at least vary in some areas, if this for an even distribution of the Gas / air mixture is required.

With the measures according to the invention, the quality of combustion as well as the robustness are improved in premixing gas burners with a cylindrical fuel element. Especially for relatively strong changing gas mixture compositions and changing volume flows of the gas burner according to the invention is particularly suitable. This problem occurs, for example, in the heating of a catalytic steam reforming unit particularly, because it must first be uniformly heated a catalyst surface with natural gas. Only upon reaching the ideal activation temperature level is then switched to residual gas from the steam reforming process, which is partially rich in hydrogen, but may even contain higher hydrocarbons and carbon monoxide. In order to avoid a second ignition of the burner, according to the innovation a high degree of modulation is ensured. The hydrogen-rich residual gas is distributed uniformly over the entire space in the interior of the inventive cylindrical fuel assembly. The corresponding cooling water temperature below the flame extinguishing temperature prevents flashback of the flame. The cooling Water in turn serves to preheat the evaporator unit of the reforming process.

The Drawing represents an embodiment of the innovation. It shows a premixing gas burner with a cylindrical Fuel:

1 in a longitudinal section,

2 : in a cross section and

3 : with an enlarged view of a corner area in longitudinal section.

The cylindrical fuel assembly is composed of a plurality of axially spaced-apart, mutually spaced slats 1 formed, which radially outward to the burner surface 2 running flow channels 3 for the gas / air mixture form. This passes through an inflow opening 4 on an end face in the interior of the fuel assembly.

The slats 1 are on tubular cooling channels 5 fixed, which approximately in the middle of the radially extending flow channels 3 are arranged for the gas / air mixture and symmetrically to the center of the fuel assembly.

At the inlet opening 4 for a gas / air mixture opposite end face is the fuel assembly with a disc-like cover 6 locked. This is inside a conical displacement body 7 attached, the tip of the inlet opening 4 shows.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 19641040 A1 [0002]
• - DE 3831624 A1 [0003]

Claims (11)

Premixing gas burner with a cylindrical fuel assembly with an inlet opening for a gas / air mixture at one end face and with cooling channels in the region below a burner surface, characterized in that the cylindrical fuel assembly of a plurality of axially juxtaposed, mutually spaced slats ( 1 ), which radially outwardly extending flow channels ( 3 ) form for the gas / air mixture. Gas burner according to claim 1, characterized in that the mutually spaced lamellae ( 1 ) of the cylindrical fuel assembly to the cooling channels ( 5 ) are fixed. Gas burner according to claims 1 or 2, characterized in that at least four cooling channels ( 5 ) in the axial direction pass through the fuel assembly. Gas burner according to one of claims 1 to 3, characterized in that the fuel element passing through the cooling channels ( 5 ) are coupled at least in pairs to each other at least one end face, so that in the axial direction at least one flow line and a return line is formed. Gas burner according to one of claims 1 to 4, characterized in that the cooling channels ( 5 ) are tubular. Gas burner according to one of claims 1 to 5, characterized in that the cooling channels ( 5 ) approximately in the middle of the radially extending flow channels ( 3 ) are arranged for the gas / air mixture and symmetrically to the center of the fuel assembly. Gas burner according to one of claims 1 to 6, characterized in that at the inlet opening ( 4 ) for a gas / air mixture opposite end face the fuel assembly with a disc-like cover ( 6 ) is closed. Gas burner according to one of claims 1 to 7, characterized in that at the inlet opening ( 4 ) for a gas / air mixture opposite end face in the interior of the fuel assembly a conical displacement body ( 7 ) is mounted, the tip of the inlet opening ( 4 ) shows. Gas burner according to one of claims 1 to 8, characterized in that the conical displacement body ( 7 ) on the disc-like cover ( 6 ) of the fuel assembly is fixed and extends approximately over half the length of the fuel assembly. Gas burner according to one of claims 1 to 9, characterized in that the mutually spaced lamellae ( 1 ) of the cylindrical fuel element over its length each have the same or different inner diameter. Gas burner according to one of claims 1 to 10, characterized in that the distances between the slats ( 1 ) of the cylindrical fuel element over its length are the same or vary at least in some areas.