JPH0639258A - Device for diffusing powdery material into gaseous stream - Google Patents

Abstract

PURPOSE: To provide a device for uniformly dispersing powder material into gaseous flow. CONSTITUTION: This device has a supply pipe 11 and a dispersing means 14. The dispersing means 14 has elongated plates 15, 17 and 19. These elongated plates 15, 17 and 19 are disposed coaxially with respect to the supply pipe 11 relatively to each other. The respective elongated plates 15, 17 and 19 are mounted at the end of the supply pipe 11 in the state that the plates are axially parted from each other in the state of approximately intersecting orthogonally with the axis of the supply pipe. The elongated plates 15 and 17 exclusive of the lowermost elongated plate 19 are respectively provided with central openings 16 and 18 for successively passing a part of the supply material to the elongated plates existing below.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a device for dispersing a powder material in a gas stream. This device comprises a supply pipe and a dispersion means.

[0002]

BACKGROUND OF THE INVENTION Devices of the type described above are disclosed in British Patent Specification Nos. 767,895 and 953,690 and U.S. Pat. Nos. 177,242 and 2,766,880.

An example of a known device is shown in FIG.
This device can be used, for example, to disperse cement in a gas stream that conveys material to a separator. This known device comprises a vertically arranged feed pipe 1 for feeding a powdered material to a stretching plate 3. The stretch plate is attached to the end of the supply pipe so as to be orthogonal to the axis of the supply pipe. The stretch plate distributes the material inside the enclosing pipe 5 symmetrically in the direction of rotation. In the enclosed pipe, an upward gas flow causes the material to plate 3.
Are forced out of and dispersed, after which the gas stream conveys the material to the separator.

The material flows laterally of the stretch plate at various rates. The thickness around the stretch plate increases as the volume of material fed increases. If the ejected layer of material becomes too thick, the gas stream will not be able to expel and disperse the layer or bed of material, which will cause the material to be dispersed in the gas stream by the gas stream. There is a problem in that the particles are not transported and are concentrated on the wall of the surrounding pipe or fall from the surrounding pipe. This causes some unnecessary pressure loss.

[0005]

SUMMARY OF THE INVENTION It is an object of the invention to provide a device which overcomes the above mentioned drawbacks.

[0006]

According to the present invention, in a device comprising a supply pipe and a dispersing means for dispersing a powder material in a gas stream, said dispersing means comprising at least two stretching plates. , These stretching plates are provided coaxially with respect to each other and with respect to the supply pipe, and are attached at the ends of the supply pipe orthogonal to the axis of the pipe and axially spaced with respect to the axis, the lower stretch plate being Each excluding stretch plate eliminates the problems of the prior art as described above by providing a central opening that allows a portion of the feed material to move to the stretch plate below.

By means of a device as described above, the feed material is distributed at several levels or heights, whereby
The thickness of the layers around each stretch plate decreases in proportion to the number of stretch plates. In this way, it is possible to maintain an appropriate bed thickness even when the feed rate is increased, and it is also possible to reduce the bed thickness as compared to known devices having only one stretch plate, Therefore, a good dispersion effect can be maintained or the dispersion effect can be improved. With the device of the present invention, the material flows from the stretch plate as a relatively thin layer so that all of the material is dispersed inside the walls of the surrounding gas supply pipe, which causes the material to fall. Or recirculation is prevented. Also, since the material is more evenly distributed, this uniform distribution of the material reduces the tendency of the gas not to pass through the localized material accumulations, thus further increasing the distribution and distribution of the gas around the dispersion means. It will be optimal.

There is some time lag or time delay between the gas flows through the various stretch plates,
This allows the stretching plate to be vertically oriented a distance of 1 to 3 times, preferably twice the diameter of the outlet of the feed pipe, in order to facilitate the filling of the gas, especially when the feed rate is large and changes rapidly. It is preferred that they are spaced.

In order to ensure that the material is evenly distributed on the individual stretch plates, it is preferred that the cross-sectional area of the stretch-plate openings be equal to n / (n + 1) times the cross-sectional area of the outlet of the feed pipe. . The above n is the number of stretching plates located below.

According to the invention, it is further preferred that the stretch plate is substantially circular.

In order to improve the dispersion effect of the stretching plates, the device can be connected to drive means and the stretching plates can be rotated around their respective connecting axes.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings.

The apparatus of the invention shown in FIG. 2 comprises a feed pipe 11 having an outlet 13 for feeding the material, and a dispersing means 14 having three stretching plates 15, 17, 19 for dispersing the material, The surrounding pipe 25 is provided, and the gas flow flows upward in the surrounding pipe.
Stretching plates 15, 17 have central openings 16, 18 respectively, while the lower plate 19 is not provided with openings.

The material supplied via the supply pipe 11 falls from the outlet 13 onto the upper stretched plate 15, on which part of the material is part of the plate 1.
5 toward the peripheral edge of the gas pipe 5 and beyond the peripheral edge of the gas pipe 2
5 enters the upwardly flowing gas stream, is dispersed in the gas and is conveyed upward in the gas pipe. On the other hand, the rest of the material falls through the opening 16 and onto the stretch plate 17 below it, on which stretch plate 15 similar to the above stretch plate 15 occurs. The last part of the material falls through the opening 18 in the stretch plate 17 into the lower stretch plate 19, from which the material is dispersed in the gas stream in the same way as in the stretch plate.

[Brief description of drawings]

FIG. 1 is a side elevational view showing a known device for dispersing powdered material.

FIG. 2 is a side elevational view showing an embodiment of the device of the present invention.

[Explanation of symbols]

11 Supply Pipe 13 Outlet of Supply Pipe 14 Dispersing Means 15, 17, 19
Stretching plates 16 and 18 Central opening

Claims (5)

[Claims] 1. An apparatus for dispersing powdered material in a gas stream, comprising a supply pipe (11) and a dispersing means (14), said dispersing means (14) comprising at least two stretch plates ( 15, 17, 19), the stretching plates being provided coaxially with respect to each other and with respect to the supply pipe (11), the stretching plate being at an end of the supply pipe (11) the axis of the supply pipe. The stretching plates (15, 15), which are attached in a state of being substantially orthogonal to and axially spaced from each other, except the lowermost stretching plate.
(17, 19) each has a central opening (16, 16) for passing a portion of the feedstock to an underlying stretch plate.
18) is provided. 2. The device according to claim 1, wherein the stretching plate (15, 17, 19) is vertically oriented at a distance of 1 to 3 times, preferably twice the diameter of the outlet (13) of the supply pipe. A device characterized by being spaced apart. 3. The device according to claim 1, wherein the cross-sectional area of the opening of the stretch plate (15, 17) is equal to n / (n + 1) times the cross-sectional area of the outlet (13) of the supply pipe. The device, wherein n is the number of stretch plates underneath. 4. Apparatus according to claim 1, characterized in that the stretching plates (15, 17, 19) are substantially circular. 5. The device according to any one of claims 1 to 4, wherein the device is the stretching plate (15, 17, 1).
Device characterized in that it is connected to drive means for rotating 9) around their respective connection axes.