JP2015178911A5 - Burner device for mixed firing, gas nozzle, swirler and boiler - Google Patents

Description

The present invention relates to a mixed combustion burner device capable of simultaneously burning different fuels, for example, a liquid fuel such as heavy oil and a gas fuel such as natural gas, a gas nozzle used in the mixed combustion burner device, a swirler, and a mixed combustion burner device. It is about the boiler which incorporated .

(3) In particular, the jet direction of the gas fuel from the pilot opening 66 is set to be the center of the virtual arrangement circle 101 in the radial direction. According to this configuration, an appropriate amount of gas can be supplied from the pilot opening 66 to the recirculation region formed by the swirler 51, and a stable pilot gas flame can be formed. In particular, this effect is significant in the gas-only firing operation. The pilot opening 66 ejects gas toward a position downstream of the opening surface 511 of the swirler 51 on the flame holding region 33 side. If it does in this way, the gas fuel injected from the gas injection opening part will mix moderately with respect to the negative pressure area | region formed in the downstream part of the swirler 51, and the stable gas flame will be formed. Further, the pilot gas opening 66 is inclined toward the central axis side with respect to the downstream side in the axial direction. In this way, since the gas jet is wound inward from the outer periphery of the circulation region, the gas fuel is suitably mixed into the circulation region without destroying the circulation flow, and a stable flame is formed.

Claims (16)

A fuel nozzle disposed on the central axis of the register;
A swirler disposed around the fuel nozzle;
In a mixed combustion burner device comprising a plurality of gas nozzles arranged at intervals on a virtual arrangement circle centered on the fuel nozzle,
In the gas nozzle,
A pilot flame gas opening through which gas fuel is injected towards a recirculation zone formed by the swirler to form a pilot flame;
A mixed combustion burner device provided with a main flame gas opening through which gas fuel is injected in order to form a main flame by the pilot flame.   The directing direction of the pilot flame gas opening is set so that the jet direction of the gas fuel from the pilot flame gas opening is minus 45 degrees to plus 45 degrees with respect to the radial center direction of the virtual arrangement circle. The mixed-burning burner device according to claim 1 set.   2. The co-firing method according to claim 1, wherein a directing direction of the pilot flame gas opening is set so that a jet direction of the gas fuel from the pilot flame gas opening is oriented in the radial center of the virtual arrangement circle. Burner device.   The co-firing burner apparatus according to claim 1, wherein the pilot flame gas opening jets gas toward a position downstream of an opening surface on the flame holding region side of the swirler.   The burner device for co-firing according to claim 4, wherein the pilot flame gas opening is inclined toward the central axis side with respect to the axial direction of the gas ejection direction.   The burner device for mixed combustion according to any one of claims 1 to 5, wherein the pilot flame gas opening is located on an outer peripheral surface of a gas nozzle. The main flame gas opening is formed between an inward radial line of a virtual arrangement circle of the gas nozzle and a tangent line of the virtual arrangement circle, and a virtual tangent in the same direction as the swirling direction of the combustion air by the swirler. The burner device for co-firing according to any one of claims 1 to 6, wherein a gas fuel ejection direction is set within an angle range.   The gas opening for the main flame is
  Between the virtual radial line formed outward in the radial direction of the gas nozzle virtual arrangement circle and the virtual tangent formed in the same direction as the swirling direction of the combustion air by the swirler, which is the tangential direction of the virtual arrangement circle The burner device for co-firing according to any one of claims 1 to 6, wherein the jet direction of the gas fuel is set within the angle range.   The gas opening for the main flame is
  The burner device for mixed combustion according to any one of claims 1 to 6, wherein the burner device is opened at a distal end portion of the gas nozzle in a radially outward direction of a virtual arrangement circle of the gas nozzle.   The co-burning burner device according to any one of claims 1 to 9, wherein the swirler is formed with a recess positioned closer to the swirler center than the outer diameter, and a gas nozzle is disposed in the recess.   The burner device for mixed combustion according to any one of claims 1 to 10, wherein a tip of the gas nozzle is formed in a conical shape.   The mixed-burning burner device according to any one of claims 1 to 10, wherein a tip of the gas nozzle is spherical.   The pilot flame hole and the main flame hole are opened on the outer peripheral surface of the gas nozzle, and the openings are opened in the radial direction from the central axis of the gas nozzle. The burner device for mixed firing as described.   The gas nozzle as described in any one of Claims 1-13.   The swirler according to claim 13.   A boiler in which the burner device for mixed combustion according to any one of claims 1 to 13 is incorporated in a boiler casing.