DD236157A1 - BURNER FOR GASOFUL FUELS - Google Patents

Abstract

The invention relates to a gas burner with a concentrically arranged to the air supply pipe gas ring with Einzelduesen and arranged in the flow direction behind the Einzelduesen dust body. The aim and the object of the invention is to provide a corresponding design of the burner head a most extreme requirements in terms of load range and stability fair burner that has good Ausbrandwerte when using different types of gas. According to the invention a gas supply pipe is arranged in the burner axis, which ends on the leeward side of the bluff body and has the shape of a truncated cone with an opening angle a of 0.5 to 0.72 prad, whose lateral surface is provided with gas outlet openings, the penetration depth h of the Gas outlet openings exiting gas jets with Staukoerperdurchmesser d a ratio of 0.35 to 0.6 forms, the ratio of emerging from the Gasaustrittsoeffnungen gas volume flow to the emerging from the Einzelduesen gas flow rate 0.15 to 0.25 and the distance a of the gas outlet openings of the Trailing edge of the Staukoerpers based on the stowage body diameter d has the value of 0 to 0.1. Fig. 1

Description

embodiment

The invention will be explained in more detail below using an exemplary embodiment. In the accompanying drawing show:

1: a burner head in longitudinal section,

2: a detail of FIG. 1,

3: a gas supply pipe with slots as gas outlet openings,

4 shows a detail of the burner head of a dual-fuel burner,

Fig. 5: a circuit diagram of the fittings in the gas supply.

In Fig. 1, a burner for gaseous fuels is shown schematically, in which a gas ring 1 is arranged concentrically to an air supply pipe 2, which is drawn radially inwardly in this area and provided with individual nozzles 3. The ratio of the number of individual nozzles 3 to the diameter of the burner mouth 4 is 0.10 to 0.12. In the burner axis, a gas supply pipe 5 is arranged, on which a bluff body 6 is attached downstream of the individual nozzles 3 in the flow direction. The ratio of its distance from the mouth to the diameter of the burner mouth 4 is 0.26 to 0.32, the ratio of the distance of the bluff body 6 from the exit plane of the gas jets from the gas ring 1 to the diameter of the burner mouth 4 0.3 to 0.6 and the ratio of the baffle diameter d to the diameter of the burner mouth 4 0.76 to 0.84. A part of the total gas volume flow, which forms a ratio of 0.15 to 0.25 with the gas volume flow emerging from the individual nozzles 3, is supplied to the gas supply pipe 5 arranged in the burner axis. The gas supply pipe 5 has at its combustion chamber end the shape of a truncated cone whose lateral surface 7 lies on the lee side of the bluff body 6 and is provided with gas outlet openings 8 (FIG. 2). The opening angle α of the truncated cone, which forms the lateral surface 7, is 0.5 to 0.72rad. The number and the diameter of the gas outlet openings 8 is chosen taking into account the gas pressure so that the ratio of penetration depth h of the gas jets 9 and the baffle diameter d has the value 0.35 to 0.6. The distance a of the gas outlet openings 8 from the trailing edge of the bluff body 6 ₍ based on the bluff body diameter _# is % = 0 ... 0.1.

3 shows a burner design for gases with low ignition speed, whose gas outlet openings are formed on the tube 5 as slots 10, in which the ratio of width to length 0.22 to 0.28.

In Figure 4, the burner head of a two-component burner can be seen, in which the gas supply pipe 5 is designed as a jacket tube, in which an oil nozzle stick 11 is arranged.

The realization of the o.g. Burner designs possible large load range is done using the reproduced in Fig. 5 arrangement of the valves in the gas supply. After a first safety barrier device 12, part of the gas flow is supplied to the gas supply tube 5 via an adjusting device 13 and the second safety shut-off device 14. The main part of the gas flow passes via an adjusting device 15 and a fen for main gas stream 2.Sicherheitsabsperreinrichtung 16 to the gas ring 1. In a running according to this structure and FIG. 1 firing device with a useful heat output of 3 MW was an increase in the load range to 1:20 achieved, wherein in the partial load range of interest for special technological claims, the upper tear limit is substantially increased. With the minimum heat output of 0.15 MW, the burner breaks off only at an air ratio of 16. If this burner is loaded with a constant amount of air required for the nominal load, the burner will break off at a minimum heat output of 0.19MW, whereas in a prior art burner this will already be 1.8MW. These results were obtained with a gas with a high methane content (> 90%).

Claims (3)

- ι - 749 39 claims: 1. Burner for gaseous fuels with a concentric with the air supply pipe arranged gas ring with individual nozzles and arranged in the flow direction behind the individual nozzles bluff body, characterized in that, as is known, in the burner axis, a gas supply pipe (5) is arranged, the gas supply pipe (5 ) on the leeward side of the bluff body (6) ends and has the shape of a truncated cone with an opening angle α of 0.5 to 0.72nrad, the lateral surface (7) of the truncated cone with gas outlet openings (8) is provided and the penetration depth h of the gas discharge openings (8) emerging gas jets (9) with the baffle diameter d forms a ratio of 0.35 to 0.6, the ratio of the gas outlet from the gas outlet openings (8) on the lateral surface (7) of the truncated cone gas volumetric flow 0.15 to 0 , 25 and the distance a of the gas outlet openings (8) from the trailing edge of the bluff body (6) on the baffle diameter d has the value of 0 to 0.1. 2. Burner according to claim 1, characterized in that in gases with low ignition speed, the gas outlet openings (8) on the lateral surface (7) of the truncated cone are formed as slots (10) in which the ratio width to length 0.22 to 0.28 is. 3. Burner according to claim 1 and 2, characterized in that the gas supply pipe (5) is designed as a jacket tube, in the inner limiting tube, an oil nozzle stick (11) is arranged. For this 3 pages drawings Field of application of the invention The invention relates to a burner for gaseous fuels with a gas ring arranged concentrically to the air supply pipe with individual nozzles and a bluff body arranged behind the individual nozzles in the flow direction. Characteristic of the known technical solutions There are already several versions of gas burners for burning different types of gas known to ensure a wide load and stability range. It is Z. B. a burner known (DD-PS 78296), in which by evenly distributed on the circumference of a pitch circle within the air supply pipe lances and arranged at the end of the lumen fire lances the gas of the combustion air is added. A baffle arranged in the flow direction in front of the gas outlet and a pilot burner arranged centrally in the air supply pipe and ending in the flow direction downstream of the baffle plate are intended to stabilize the flame. However, this gas burner has one for many applications, eg. As ovens of the chemical industry, insufficient load and stability range. This burner achieves a load ratio of 1: 5.5. The demolition limit for the flame is at rated load at an air ratio of 1.2 and at partial load at about 2.2. A burner for gaseous and liquid or gaseous fuels (DD-WP F 23 D / 222 524) has a concentric with the air supply pipe arranged gas ring with individual nozzles and arranged at a defined distance in the flow direction behind the individual nozzles baffle plate. Certain geometrical relationships and dimensions lead to very good burnout values, a relatively large load range of 1: 6 and a flame cut-off limit with an air ratio of 1.6 at rated load and approx. 2.0 at partial load. These parameters are still not sufficient for the requirements of certain processes of chemical engineering. Object of the invention The aim of the invention is to provide a burner that also meets extreme requirements in terms of load range and stability with very good burnout even with different types of gas. Explanation of the essence of the invention The object of the invention is to significantly increase the load and stability range of a burner for different gaseous fuels by appropriate design of the burner head while ensuring very good burnout parameters. According to the invention the object is achieved in that in the burner axis, as known per se, a gas supply pipe is arranged, the gas supply tube ends fire chamber side on the lee side of the bluff body and has the shape of a truncated cone with an opening angle α of 0.5 to 0.72 jrrad , the lateral surface of the truncated cone is provided with gas outlet openings and the penetration depth h of the gas jets emerging from the gas outlet openings with the baffle diameter d forms a ratio of 0.35 to 0.6, the ratio of the gas flow exiting the gas outlet openings on the lateral surface of the truncated cone to the from the individual nozzles escaping gas flow rate is 0.15 to 0.25 and the distance a of the gas outlet openings of the trailing edge of the bluff body based on the bluff body diameter d has the value of 0 to 0.1. For gases with low ignition speed, it is expedient in a development of the invention to form the gas outlet openings on the lateral surface of the truncated cone as slots, in which the ratio width to length is 0.22 to 0.28. To maintain security of supply, a dual-fuel burner for gaseous and liquid fuels is required in many cases. This requirement is met in a further embodiment of the invention in that the gas supply pipe is designed as a jacket tube, in the inner limiting tube, an oil nozzle stick is arranged. These burners have a very high load and stability range as well as very good burnout values even when using different types of gas.