JP3698041B2 - Low calorie gas burning burner - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a burner for low-calorie gas combustion such as partial combustion gas generated in waste treatment or the like. The burner of the present invention is used as a burner for burning partially burned gas containing unburned char generated in a gasification furnace, particularly in a fluidized bed waste gasification and melting system, by burning waste in a gasification furnace. Suitable for
[0002]
[Prior art]
Partial combustion gas generated by burning waste, such as waste in a fluidized bed gasifier, with low air ratio combustion varies greatly in calories and quantity depending on the waste quality, etc., and unburned char (unburned ash) with high chlorine concentration ), It has the following problems.
(1) The partial combustion gas of garbage has strong adhesion because it contains unburned char with high chlorine concentration. For this reason, when obstacles such as swirl vanes are arranged in the partial combustion gas channel, chlorides adhere and grow, causing the channel to be blocked.
(2) Partial combustion gas is low in calories, and its properties change depending on the quality and quantity of garbage.
In addition, since the quality and quantity vary finely due to instantaneous fluctuations in the upstream process, flame holding is difficult.
(3) When the swirl vanes are not attached to the partial combustion gas flow path, the mixing with the air in the furnace is poor, and the heat generation load in the combustion region is low.
[0003]
Japanese Patent Application Laid-Open No. 2000-55340 discloses a nozzle at the tip of a burner, which is a fuel supply nozzle, a primary combustion gas supply nozzle, an object supply nozzle, and a secondary combustion gas supply nozzle from the center to the outer periphery. In this order, incinerator fly ash melting treatment oxygen burners arranged concentrically as a whole are described.
Japanese Patent Application Laid-Open No. 52-65330 discloses a primary air nozzle at the center, a fuel gas nozzle at the outer periphery thereof, and a secondary air nozzle at the outermost periphery concentrically. A method of operating a two-flow external mixing type low pressure gas burner is described in which air at a constant flow rate of 3 to 10% of the total amount of combustion air is constantly supplied from a nozzle.
[0004]
[Problems to be solved by the invention]
In the burner disclosed in Japanese Patent Application Laid-Open No. 2000-55340, since the workpiece supply nozzle has an oblong hole, clogging occurs due to chloride contained in the unburned char in the partial combustion gas. Since the burner disclosed in JP-A-52-65330 is a high calorie gas burner, stable flame holding cannot be obtained when a low calorie gas with large fluctuations in gas quality and quantity is burned. For this reason, the partial combustion gas burner prevents clogging due to adhesion of chlorides, and enables stable combustion even if the partial combustion gas fluctuates in both quality and quantity, that is, it can reliably hold the flame without misfiring. There must be.
[0005]
The present invention has been made in view of the above points, and an object of the present invention is to sufficiently mix the low calorie gas and the oxidizing agent without blocking the flow path, to prevent misfire and to achieve stable flame holding. Another object of the present invention is to provide a low-calorie gas combustion burner with good combustion efficiency.
[0006]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the low-calorie gas combustion burner of the present invention comprises a highly adherent chloride , which is a partial combustion gas containing unburned char generated in a fluidized bed waste gasification and melting system. In a burner that burns low-calorie gas containing, a fuel burner is arranged in the center, and an internal oxidant supply passage, a low-calorie gas passage, and an external oxidant supply passage are sequentially arranged in a circular pattern outside the fuel burner, and internal oxidation A swirl vane is attached to the agent supply passage and the external oxidant supply passage, the obstruction to which chloride adheres in the low calorie gas passage is eliminated, and the blockage of the passage is eliminated, and a wind box is provided at the low calorie gas inflow portion, The low calorie gas inflow pipe is configured to be tangentially connected to the wind box so that the low calorie gas is introduced as a swirl flow (FIGS. 1 and 2). See Figure 3).
As the oxidizing agent, air, oxygen, oxygen-enriched air, or the like is used at normal temperature or warmed. As fuel, fuel oil such as heavy oil and light oil, fuel gas, and the like are used.
[0007]
In this low-calorie gas burning burner, the fuel burner, the internal oxidant supply passage, the low-calorie gas passage, and the external oxidant supply passage may be concentrically arranged. In this case, it goes without saying that the central fuel burner need not be concentric.
In addition, a wind box is provided at the low calorie gas inflow portion to further mix with the oxidant, and the low calorie gas inflow pipe is tangential to the wind box so that the low calorie gas is introduced as a swirling flow. It can be set as the connected structure (refer FIG. 2, FIG. 3).
In this case, furthermore, the turning force can be made moderate by attaching the low calorie gas inflow pipe obliquely in the downstream direction with respect to the burner axis (see FIG. 4).
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, although the case where air is used as an oxidant will be described as an embodiment of the present invention, the present invention is not limited to the following embodiment, and can be implemented with appropriate modifications. .
FIG. 1 is a schematic longitudinal sectional view showing an example of a low-calorie gas combustion burner according to the first embodiment of the present invention. FIGS. 2 and 4 are vertical cross-sectional views of other examples of the low-calorie gas combustion burner. FIG. 3 shows an enlarged sectional view taken along line AA of FIGS.
As shown in FIG. 1, an inner (inner) air supply passage (flow passage) 12 is provided around the outer side of the central fuel burner 10, and a low calorie gas passage (flow) is provided outside the inner air supply passage 12. 14) is provided around the low-calorie gas passage 14, and an external (outside) air supply passage (flow passage) 16 is provided outside the low-calorie gas passage 14, and the internal air supply passage 12 and the external air supply passage 16 are provided inside. The swirl vanes 18 and 20 are attached to each other. The swirl blades 18 and 20 include a plurality of blades for swirling the air flow, and these blades are fixed in the passages 12 and 16. 22 is a melting furnace or a combustion furnace.
[0009]
In the low-calorie gas combustion burner configured as described above, fuel oil, for example, heavy oil, is supplied to the fuel burner 10, and low-calorie gas, for example, partial combustion gas, is supplied to the low-calorie gas passage 14, and the internal air supply passage 12. Internal (inside) air and external air supply passage 16 are supplied with external (outside) air.
[0010]
When such a combustion burner is used, since there is no obstacle to which chloride adheres in the low calorie gas passage, there is no blockage of the flow path. Further, the low-calorie gas is sandwiched between air swirled by the swirl vanes 18 and 20 in FIG. 1, preferably preheated air, and mixing is promoted to improve combustion efficiency.
The fuel burner 10 has an oxidizing atmosphere around the internal air and forms a stable flame. By using the flame as an ignition source, it was possible to burn low-calorie gas that fluctuated greatly. Therefore, the fuel burner 10 is always used by burning a small amount of heavy oil in order to ensure flame holding during low calorie gas combustion.
[0011]
2 is a longitudinal sectional view showing another example of a low-calorie gas combustion burner, FIG. 4 is a longitudinal sectional view showing another example of the low-calorie gas inflow pipe in FIG. 2, and FIG. 3 is A in FIG. FIG. A substantially inverted frustoconical wind box 34 is provided above the low calorie gas inlet 32 of the low calorie gas passage 14, and the low calorie gas inflow pipe 36 is connected to this wind so that the low calorie gas is introduced as a swirl flow. The box 34 is connected in a tangential direction.
Further, as shown in FIG. 4, when the low calorie gas inflow pipe 36a is inclined obliquely downstream with respect to the burner axis, that is, the turning force is adjusted by changing the inflow angle θ. There is. In this case, the inflow pipe 36a may be fixed or movable. Thus, by swirling the low calorie gas, mixing with the internal and external air is further promoted, and more efficient combustion is achieved. Other configurations and operations are the same as those in FIG.
[0012]
【The invention's effect】
Since this invention is comprised as mentioned above, there exist the following effects.
(1) Since obstacles such as swirl vanes are not provided in the low-calorie gas passage, even if unburned char (unburned ash) having a high chlorine concentration passes, it can be stably operated without being blocked.
(2) Since the low-calorie gas is sandwiched and stirred between the strong swirling internal air and the strong swirling external air, the mixing of the gas and air is good, and the combustion efficiency is improved even with the low-calorie gas.
(3) Since the center of the fuel burner is made an oxidizing atmosphere with internal air to stabilize the flame and use it as an ignition source, it will not misfire even if the quality and quantity of low-calorie gas varies.
[Brief description of the drawings]
FIG. 1 is a schematic longitudinal sectional view showing an example of a low calorie gas burning burner according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view showing another example of a low-calorie gas combustion burner.
3 is an enlarged sectional view taken along line AA in FIGS. 2 and 4. FIG.
4 is a longitudinal sectional view showing another example of the low calorie gas inflow pipe in FIG. 2. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Fuel burner 12 Internal air supply path 14 Low-calorie gas path 16 External air supply path 18, 20 Swirling blade 22 Melting furnace or combustion furnace 32 Low-calorie gas inlet 34 Wind box 36, 36a Low-calorie gas inlet pipe

Claims (3)

In a burner that burns low-calorie gas containing highly adherent chloride , which is a partial combustion gas containing unburned char generated in a fluidized bed waste gasification and melting system, a fuel burner is arranged in the center and the fuel An internal oxidant supply passage, a low calorie gas passage, and an external oxidant supply passage are provided around the burner in order, and swirl vanes are attached to the internal oxidant supply passage and the external oxidant supply passage. The low calorie gas inflow pipe is connected to the low calorie gas so that the obstruction to which chloride adheres is eliminated, the flow path is blocked, a wind box is provided at the low calorie gas inflow part, and the low calorie gas is introduced as a swirling flow. A burner for low-calorie gas combustion, characterized in that it is connected tangentially to the wind box.   The burner for low-calorie gas combustion according to claim 1, wherein the fuel burner, the internal oxidant supply passage, the low-calorie gas passage and the external oxidant supply passage are arranged concentrically.   The burner for low-calorie gas combustion according to claim 1, wherein the low-calorie gas inflow pipe is attached to be inclined obliquely downstream with respect to the burner axis.

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