JPH0320717Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a gas dispersion nozzle for a fluidized bed furnace.

The performance required for the above gas dispersion nozzle is (1) heat resistance, (2) durability,
(3) Uniform fluidization can be obtained at any temperature;
(4) There is little heat transfer from the bottom of the retort.

BACKGROUND ART Conventional gas dispersion nozzles are designed as shown in FIGS. 7 to 9.

The conventional example shown in FIG. 7 has a structure in which a nozzle b is opened at the bottom of a porous ceramic dispersion plate a.

The conventional example shown in FIG. 8 has a configuration in which nozzles d are attached to a number of holes in a dispersion plate c.

In the conventional example shown in FIG. 9, a bolt g is loosely fitted into a sleeve f fixed to a dispersion plate e, and gas is ejected through a gap h between the bolt g and the sleeve f.

Problems that the invention aims to solve The problem shown in Figure 7 above is that (1) the dispersion plate a is made of ceramic and is therefore prone to breakage, and (2) the adhesive i that fixes the dispersion plate a to the retort is susceptible to heat. Because it is weak, it must be cooled with cooling air from outside the retort, resulting in heat loss. (3) To protect the adhesive, the temperature is lowered to 700℃ before fluidization is stopped.
There is a problem in that both time and heat are lost.

The ones shown in FIGS. 8 and 9 are (1) expensive because the nozzle processing is complicated and there are a large number of them. (2) Since the nozzle pressure drop is large, a larger blower is required, and when used in a heat circulation type fluidized bed, the circulation efficiency will be poor. (3) Since the nozzle is oriented horizontally, fluid particles can easily enter, causing the nozzle to become clogged. (Four)
Since the dispersion plate has many holes and supports the weight of the particles, there were problems such as the maximum temperature was 1100°C and it could not be used at higher temperatures.

Means and Effects for Solving the Problems The present invention was developed in view of the above, and includes a central pipe that is erected at the center of the bottom of the retort with its upper end closed and its lower end connected to piping; It consists of multiple nozzle pipes that are attached radially to the central pipe at separate locations and have multiple nozzle holes in the longitudinal direction on the bottom, and the fluidizing gas that flows into the central pipe is routed through each nozzle. It is sprayed from the nozzle hole of the pipe toward the bottom of the retort, then reverses and rises above the retort.
During this time, the fluidized particles are brought into a fluidized state.

Embodiment An embodiment of the present invention will be described based on FIGS. 1 to 6.

In the figure, 1 is a retort surrounded and supported by a heat insulating material 2,
3 is a combustion chamber provided around the lower side of the retort 1, and 3a is its burner. Although not shown, a necessary amount of fluidized particles is charged into the retort 1. 4 is a gas dispersion nozzle provided at the bottom of the retort 1. This gas dispersion nozzle 4 is connected to the retort 1
It consists of a central pipe 5 located at the center of the bottom of the pipe, and a number of nozzle pipes 6 radially attached to the central pipe 5. The central pipe 5 is erected in the retort 1, its upper end is closed, and its lower end is connected to piping outside the furnace. Further, the nozzle pipes 6 are attached at positions slightly apart from the bottom surface of the retort 1, and nozzle holes 7 are provided at appropriate intervals in the longitudinal direction, for example, at intervals of 30 mm, on the lower side of each nozzle pipe 6.

In the above configuration, the fluidizing gas that has flowed into the central pipe 5 is injected from the central pipe 5 toward the bottom surface of the retort 1 through the nozzle holes 7 of the respective nozzle pipes 6. This injected fluid gas is then transferred to the retort 1.
The particles collide with the bottom of the particle, turn around, and rise, during which time the particles become fluid.

When the diameter of the retort 1 is large, it is not possible to improve the flow on the wall surface only with the radial nozzle pipes 6 as in the above embodiment, so as shown in FIG. A nozzle hole is also provided on the lower side of this pipe 8.

If the diameter of the retort 1 is even larger, in order to increase the number of nozzle pipes 6, as shown in FIG. Install it by shifting it up and down.

Effects of the invention According to the invention, the following effects can be achieved.

(1) Since the gas dispersion nozzle is made of a pipe, it is heat resistant and durable, and can be used up to a maximum of 1300℃.

(2) The structure is simple and inexpensive.

(3) Easy to replace.

(4) Uniform fluidization can be obtained at any temperature.

(5) Since the nozzle diameter can be increased, the pressure drop of the fluidized gas is small, making it suitable for thermal circulation type fluidized beds.

(6) Since the entire nozzle pipe is inside the particles, it is not affected by the weight of the particles and is advantageous in terms of strength.

(7) Since the particles below the nozzle pipe are not flowing, this part becomes a heat insulating layer and can prevent heat from flowing to the lower part of the retort.

[Brief explanation of drawings]

Figures 1 to 6 show an embodiment of the main parts of the present invention, with Figure 1 being a longitudinal sectional front view, Figure 2 being a cross-sectional plan view, and Figure 3 being a partially cutaway front view of the gas dispersion nozzle. , FIG. 4 is an enlarged sectional view taken along the line - in FIG. 3, FIGS. 5 and 6 are plan views and partially cutaway front views showing different embodiments of the gas dispersion nozzle, and FIG. FIG. 9 is a sectional view showing a conventional example. 1 is the retort, 5 is the center pipe, 6 is the nozzle pipe, and 7 is the nozzle hole.

Claims (1)

[Scope of utility model registration request] Close the top end and connect the bottom end to the piping to connect retort 1.
A central pipe 5 stands upright at the center of the bottom surface of the retort 1, and a plurality of nozzles are attached radially to the central pipe 5 at positions spaced apart from the bottom surface of the retort 1, and have a plurality of nozzle holes 7 provided in the longitudinal direction on the lower side. A gas dispersion nozzle for a fluidized bed furnace, characterized in that it consists of a pipe 6.