JPS5843652B2 - Powder processing material supply nozzle device - Google Patents

Description

[Detailed description of the invention] The present invention uses electrostatic precipitated ash (hereinafter referred to as EP ash).

), the structure of the powder feed nozzle of a swirling spouted bed combustion furnace that burns powder processed materials such as

In recent years, prevention of air pollution caused by industrial waste has become extremely important, and the amount of nitrogen oxides (NOx) in combustion exhaust gas from boilers has been regulated in particular. A combustion method is used that lowers the temperature and reduces the supply of combustion air to reduce the amount of NOx.

For this reason, a large amount of EP ash, which is a powdered product obtained by collecting waste containing low-melting-point compounds, such as dust containing carbon components contained in boiler combustion gas, with an electrostatic precipitator is produced. It is desired to develop an incinerator that can burn waste quickly and without pollution.

However, EP ash contains substances with low melting points such as vanadium (V) and sodium chloride (Na), which causes the problem of melting and solidification during incineration.

Regularly incinerating EP ash, which contains low-melting-point substances and whose calorific value and throughput fluctuate, involves various problems, and it has been difficult to deal with them. A stratified swirling spouted bed combustion furnace was proposed and achieved considerable success.

However, EP ash is fine particles of about 10 to 30 microns and contains 20 to 30 parts of ammonium sulfate ((NH,) 2804.
In order to supply EP ash to the fluidized bed section, which has an internal furnace density of approximately ++ mH2O, it is best to use an air flow transport method in which the EP ash momentarily holds the EP ash supply nozzle section, which is affected by heat. method is adopted.

This is (NH,) 280. If it contains EP
When ash stagnates in a high temperature area, it becomes sticky at around 250℃,
This is also to prevent it from adhering to the supply hole.

However, this type of conventional supply nozzle device uses only one supply nozzle for one fluidized bed section.
In addition, because no special consideration is given to its direction or orientation, in the case of incinerators with a small fluidized bed section with a diameter of less than 1 m, EP ash is dispersed throughout the bed due to the swirling force that is a feature of the swirling spouted bed. Although it is possible, if the combustion furnace has a swirling fluidized bed section with a diameter of 1 m or more, the EP ash 2 supplied from one supply nozzle 1 will flow into the swirling spouted bed 3a as shown in FIG. The feed nozzle 10 is not evenly distributed throughout the layer in the
Since the particles are concentrated nearby, efficient combustion cannot be performed in the entire spouted bed 3a, making it difficult to improve the performance of the incinerator.

Furthermore, the air in the air flow caused flow obstruction, and the generation of excessive bubbles caused the EP ash to bypass the layer, etc., causing negative effects.

The present invention has been made to eliminate the drawbacks of the prior art as described above, and focuses on the fact that even if the supply nozzle is extended into a high-temperature fluidized bed part, the nozzle will not burn out due to the cooling effect of the transport air. By arranging the main supply nozzle to face downward in the substantially tangential direction of the swirling jet, the length of its protrusion into the jet layer and the angle of inclination with respect to the wall surface can be freely adjusted.
It is possible to prevent uneven distribution of EP ash in the spouted bed, increase the swirling force of the spouted bed to activate the flow, and improve the dispersibility of EP ash. The object of the present invention is to propose a supply nozzle device for a swirling spouted bed combustion furnace that allows rapid combustion.

The present invention will be explained below with reference to the drawings.
As shown in the figure, a swirling spouted bed combustion furnace 4 has a funnel-shaped perforated plate 5 at the bottom, through which combustion air is supplied, forming a swirling flow in the fluidized bed 3 of the furnace, and preventing the adhesion of low-melting materials. This is to prevent this by burning at a relatively low temperature.

The wind box 7 is provided below the perforated plate 5, a swirling air nozzle 8 is attached to its outer periphery, and a jet hole 9 is provided in the center, into which the jet air nozzle 1 is installed.
0 are provided in series.

A refractory 11 forms the furnace wall, and on the circumference of the refractory there are a plurality of seal air boxes 12 and seal air nozzles 13 extending from the seal air boxes toward the fluidized bed 3.
is inserted tangentially and downwardly to the swirling jet.

This seal air box 12 and seal air nozzle 13
is constantly pressurized at a pressure of about 1000+++πH20 to prevent the high-temperature gas in the spouted bed 3 from spewing out to the outside.

The inside of these seal air nozzles 13 is hereinafter simply referred to as a powdered material supply nozzle C.

) 14 is slidably inserted, and its tip 14a protrudes into the flow 3, and the length of this protrusion is adjustable.

Although the embodiment shown in the drawings shows a case where four supply nozzles 14 are used, this number may be determined as appropriate depending on the diameter of the fluidized bed 3.

In addition, in FIG. 3, the adjustment range of the distance between the tip 14a of the supply nozzle 14 and the refractory 11, that is, the amount of protrusion of the supply nozzle, is shown as an example. When R is the radius of the spouted bed 3, A =C=50-100mm, B=3/R, D=/R are suitable.

In addition, as shown in Fig. 3, the protrusion amount is different and the EP
It is best to distribute and evenly supply ash.

With this configuration, air is sent from the jet holes 9 toward the upper part of the spouted bed 3, a violent vertical jet is generated in the fluidized bed 3, and air for swirling is sent from the perforated plate 5 to the top of the spouted bed 3.
As a result, a strong swirling flow is generated in the fluidized bed 3, which is combined with the above-mentioned vertical jet to generate a swirling jet.

On the other hand, in addition to this, a powdered material such as EP ash is ejected from the supply nozzles 14 into the fluidized bed 3 in the tangential direction of the swirling flow in the direction of each nozzle 14, creating a new swirling flow with a different radius. This promotes the swirling action of the fluidized bed 3, making the flow more active, and since the supply nozzle 14 is provided facing downward, the flow near the perforated plate 5 is also activated, and the perforation of the perforated plate 5 is also reduced. Powdered materials such as EP ash are dispersed widely and evenly within the spouted bed 3, and are completely combusted by an appropriate in-bed burner.

The position of the supply nozzle for supplying the powdered material should be such that the displacement of its opening in the direction of the nozzle axis, that is, the amount of protrusion, can be adjusted.If necessary, the part of the supply nozzle that penetrates the furnace wall should be set with a spherical body, for example. With the flexible connection held at 15, it is possible to freely adjust the inclination angle α of the supply nozzle with respect to the furnace wall surface and the inclination angle β (see Fig. 2) in the longitudinal section including the incinerator axis. .

A passage for seal air is provided in the spherical body 15 to prevent the spherical body 15 from burning out.

In short, this invention makes it possible to appropriately select the opening position of the supply nozzle that supplies the powdered material within the spouted bed.
The device is characterized by ejecting powdered processed materials such as EP ash in the tangential direction to the spouted bed flow, ensuring rapid and even distribution of the EP ash within the layer, and enabling sufficient combustion treatment and continuous operation. do.

According to a first feature of the invention, EP
The ash, etc. is ejected and the swirling jet action is further activated, thereby the EP ash, etc. is uniformly dispersed throughout the spouted bed.
This has the effect of making it possible to incinerate P ash, etc.

Furthermore, by uniformly dispersing EP ash, etc. throughout the spouted bed, the residence time of EP ash, etc. within the bed becomes longer, the incineration rate increases, and the temperature within the bed becomes uniform and stable, resulting in a good condition. The effect of enabling driving can be obtained.

Furthermore, according to the second feature of the present invention, it is possible to set the supply nozzle at the optimum position while observing the situation inside the furnace, and by using a shielded air nozzle, the high temperature gas in the spouted layer can be spouted to the outside. It is safe because it prevents
Further, it is possible to easily adjust the supply nozzle, and when the furnace is stopped, the supply nozzle can be pulled out of the incinerator, thereby preventing the supply nozzle from being burnt out.

In addition, since the supply nozzle is installed downward, even in a spouted bed with a funnel-shaped bottom, EP ash etc.
This has the effect of sufficient dispersion.

Furthermore, various effects can be obtained, such as preventing flow obstruction due to air transport, bypassing of EP ash, etc. in the layer due to generation of excessive bubbles, and preventing adverse effects due to uneven distribution of EP ash within the layer.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of a conventional supply nozzle device, Fig. 2 is a longitudinal sectional view of the device of the present invention, Fig. 3 is a cross sectional view taken along the ■-■ arrow in Fig. 2, and Fig. 4 is FIG. 2 is an enlarged detailed view of part A of FIG. 3...Fluidized bed, 4...Swirling jet combustion furnace, 14...Powdered material supply nozzle, 15...
...Spheroidal body.

Claims (1)

[Claims] 1. In a fluidized bed combustion furnace in which a powdered material containing a low melting point compound is transported by air flow and is supplied to a swirling flow of a fluidized medium and combusted, the axial center of a plurality of powdered material supply nozzles is A nozzle device for supplying powdery processed material, characterized in that the nozzle is oriented substantially tangentially and downwardly to the swirling flow and protrudes into the layer at the open end thereof. 2. The axis of a plurality of powdered material supply nozzles is set almost tangent to the swirling flow in a fluidized bed combustion furnace in which a powdered material containing a low melting point compound is transported by pneumatic flow and supplied to the swirling flow of fluidized medium C for combustion. In the case where the powdery material supply nozzle is directed downward and protrudes into the fluidized bed at its open end, the powdery material supply nozzle passes through a sealed air box provided on the wall surface of the fluidized bed combustion furnace, and the powdery material is fed into the fluidized bed. What is claimed is: 1. A nozzle device for supplying powdery processed material, characterized in that the amount of protrusion from the wall surface can be adjusted so that the powdery material can be supplied evenly and dispersedly within the interior of the wall. 3. Powdered materials containing low melting point compounds are transported by pneumatic flow and supplied to the swirling flow of a fluidized medium for combustion. The furnace wall of the fluidized bed combustion furnace, which is tangentially directed downward and protrudes into the fluidized bed at its open end, is characterized in that a portion of the furnace wall of the fluidized bed combustion furnace through which the supply nozzle passes is freely connected with a sealed air box. Powder processing material supply nozzle device.