JPH0159537B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for collecting solid particles suspended in the atmosphere, such as dust.

In the past, in order to monitor the state of air pollution, it was necessary to collect particles suspended in a gas according to particle size and analyze their components. As a means for classifying and collecting particles according to particle size, an inertial impactor 1 as shown in FIG. 1 is generally used.

This impactor 1 is composed of stages 2 and after filters 3 provided in multiple stages, and each stage 2 is provided with a nozzle 4,
The diameter of the nozzle 4 gradually decreases from the upper stage to the lower stage.

Now, when a gas containing solid suspended particles of different sizes is supplied from the direction of arrow A while suctioning from the suction port 5 with a pump, if there is an obstacle in the direction of travel, small particles will easily advance in front of the obstacle. While changing direction, large particles collide with obstacles due to their large inertia.

Further, since the aperture of the nozzle 4 is gradually reduced, different flow velocities occur in each stage 2.
Therefore, if the particle collection plate 6 is placed below the nozzle 4,
Depending on the flow rate generated in each stage, particles can be sorted and attached to a particle collection plate in order from large particles to small particles using inertia force, and then collected.

However, in such a conventional inertial impactor 1, since the nozzle 4 has only one hole, the distribution of particles adhering to and classified on the collection plate 6 becomes a mountain-shaped bulge directly below the nozzle.

On the other hand, fluorescent X-ray analysis, proton-excited X-ray analysis, and other methods will become promising in the future as methods for analyzing the components of classified and collected particles. Because it requires something,
These analytical methods had the disadvantage that they could not be applied to the analysis of classified and collected particles.

Therefore, the present invention was made to eliminate such conventional drawbacks, and uses a simple mechanism to classify solid suspended particles onto a collection plate to a uniform thickness according to their respective particle sizes. It has the advantage that it can be collected, and therefore the collected solid particles can be immediately provided as a test subject for X-ray analysis or proton-excited X-ray analysis.

That is, the solid suspended particle collection device of the present invention has the following features:
A solid material formed by forming multiple stages of compartments, each having a nozzle with a diameter gradually narrowing from the upper stage to the lower stage on the partition wall provided between the compartments, and installing a solid suspended particle collection plate below each nozzle. In the suspended particle collection device, the partition wall is rotatable by an external drive device, and a porous disk is attached to the nozzle, in which the same number of ejection holes are formed on ring zones divided into equal areas. This is a characteristic feature.

The present invention will be described below based on embodiments shown in the drawings.

Fig. 2 is a schematic perspective view of the collection device of the present invention;
The figure is a side view, FIG. 4 is a partial vertical cross-sectional view, FIG. 5 is a cross-sectional view, and FIG. 6 is a partial cutaway perspective view.

That is, the solid suspended particle collection device of the present invention has the following features:
One section is formed by the disk 11 and the cylindrical jacket 12, and this section is assembled in multiple stages on the same axis.

The disk 11 that serves as the partition wall of these sections is rotatable, and has a gear 13 formed on its circumferential surface as shown in FIG. gear 14
is rotated by a motor 15 via a drive shaft 16. Further, as shown in FIG. 4, a nozzle 17 is formed in the center of the disk 11, and the diameter of the nozzle 17 becomes smaller as it goes from the top disk 11 to the bottom disk. Each nozzle 17 has a perforated disk 18 attached thereto.

On the other hand, on the outer surface of the cylindrical mantle 12, as shown in FIGS. 2 and 5, protrusions 19, 19 are provided integrally with the mantle 12, respectively.
A recess 20 is formed in each of the holes 19 . Then, each protrusion 1 of each mantle 12 stacked in multiple stages
As shown in FIG. 2 and FIG.
2 pass through, and the discs 11 and the mantle 12 are alternately fixed by a frame 23 and nuts 24.

Furthermore, in the present invention, solid suspended particle collection plates, such as particle collection sections 25, are provided in the cylindrical jacket 12, as shown in FIGS. 4, 5, and 6, respectively. The particle collecting section 25 is a polygonal drum 2
6 and rotating means 27, and as shown in FIG. As shown in FIG.

The polygonal drum 26 may have any polygonal shape as long as it has a flat surface on which the solid suspended particles that have passed through the perforated disk 18 provided in the nozzle 17 collide, and the size of the drum 26 is as follows: If expressed as a cylindrical drum, it would have a diameter of 2 cm and an axial width of about 5 mm.

A pulse motor, a rotary solenoid, or the like is used as the rotating means 27, and a new surface of the polygonal drum 26 is made to face the nozzle 17 at predetermined intervals.

Note that an O-ring 29 made of Teflon rubber or butyl rubber is provided at the contact portion between the disc 11 and the cylindrical jacket 12.
is filled to maintain the airtightness of the cylindrical jacket and to allow the disc 11 to rotate smoothly.

The O-ring 29 can also be used by applying grease.

As shown in FIG. 7, the porous disk 18 has the same number of small-diameter nozzles 31, for example, one each, arranged on each ring zone 30 of equal area, and the size of the ring zone 30 is usually as follows. Width 2~10mm, number of rings 20~
It is 200. In addition, the diameter and number of the jet ports provided on this annular zone can be arbitrarily selected depending on the suction amount and flow rate of the gas containing solid suspended particles supplied into the device, but usually the flow rate is 10 m to 300 m/min. Selected in seconds. Further, the positions of the jet ports are not particularly limited as long as the number is the same for each ring zone.

Figure 7 shows an example of a perforated disc in which one group of small holes with a diameter of 0.2 mm is arranged in each of 43 annular zones to obtain an ejection velocity of 40 m/sec for a suction amount of 5/sec. It is set up.

Next, the functions of the solid suspended particle collection device 10 according to the present invention will be described with reference to FIGS. 3, 4, and 8.

Now, air containing solid suspended particles of different particle sizes is
When the gas containing solid particles is introduced into the device 10 from the supply pipe 33 along the arrow A while being suctioned by the vacuum pump 32, the solid particle gas flows into the nozzle 1 of the uppermost disk 11.
The spout 3 formed in the disk 18 attached to 7
1 and flows along the outer edge of the polygonal drum 26 in the direction of arrow B while impinging on the surface 26A of the polygonal drum 26. At this time, since the disk 11 shown in FIG. 7 is rotating at a rate of 0.1 to 10 times/min, the surface 26A of the polygonal drum 26 has a density distribution C as shown in FIG. Solid particles are collected with a substantially uniform thickness.

In addition, in the porous disk 18 shown in FIG.
The number of holes increases as the circumference approaches the circumference, but since the distance traveled by the rotation of the porous disk 18 becomes longer, the amount of particles that pass through the holes and adhere is averaged out, as shown in Figure 9. It is deposited to approximately the same thickness.

Next, solid particles having a smaller diameter than the solid particles that flowed along the peripheral edge of the polygonal drum in the direction of arrow B in the uppermost disk, that is, the solid particles that were collected on the surface 26A of the polygonal drum 26, are The solid particles are the second
It is guided to the third stage disc, passes through a nozzle with a smaller diameter, and is collected on the surface of a polygonal drum in the same manner as described above.

In this way, as you get to the lower disk,
Since it passes through a small-diameter nozzle, solid particles of small diameter are collected one after another, and solid particles of the smallest diameter are collected by the polygonal drum at the lowest stage.

Note that the gas discharged from the lowermost cylindrical mantle is guided to the vacuum pump 32 through the filter 33.

Further, by rotating the polygonal drum 26 by the pulse motor 27, solid particles can be collected again on the next surface of the polygonal drum 26.

As described above, according to the present invention, a perforated disk is attached to a nozzle formed at the center of a rotatable disk, and a polygonal drum having a flat surface facing the perforated disk inside the cylindrical jacket. , and the porous disk has the same number of ejection holes formed on the annular zones divided into equal areas, so that the solid suspended particles in the supplied gas pass through the ejection holes of the rotating porous disk. When classified and collected on opposing polygonal surfaces, a substantially equal density distribution of the largest solid particles, that is, a layer with substantially equal thickness is formed.

Solid particles with a smaller particle size than the collected solid particles pass through the cylindrical jacket to the next stage of stacked discs, and are transferred to a rotating perforated disc provided in a nozzle with a smaller diameter. While passing through, it is classified and collected.

In this way, solid particles are sequentially classified and collected. Moreover, the collected particle layer is not collected in a heap only under the nozzle as in the conventional case, and a collection layer having a substantially uniform thickness is formed.

Therefore, the obtained collection layer has a uniform thickness and can be immediately supplied as a specimen for fluorescence X-ray analysis or proton-excited Analysis is accomplished.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing conventional solid suspended particles, Fig. 2 is a perspective schematic view showing an embodiment of the present invention, Fig. 3 is a side view thereof, Fig. 4 is a partial vertical sectional view thereof, and Fig. 5
6 is a partially cutaway perspective view of the cylindrical mantle, FIG. 7 is a plan view of the porous disk, FIG. 8 is an explanatory diagram showing the flow of gas containing solid suspended particles, and FIG. 9 is a cross-sectional view of the same. The figure shows the density distribution of solid suspended particles collected on the surface of a polygonal drum. DESCRIPTION OF SYMBOLS 10... Solid suspended particle collection device, 11... Disc, 12... Cylindrical mantle, 17... Nozzle, 18...
... Porous disk, 30 ... Ring zone, 31 ... Outlet hole.

Claims (1)

[Claims] 1 A plurality of compartments were formed, and a nozzle whose diameter gradually narrowed from the upper stage to the lower stage was installed on the partition wall provided between the compartments, and a solid suspended particle collection plate was installed below each nozzle. In the solid suspended particle collection device, the partition wall is rotatable by an external drive device, and a porous disk is attached to the nozzle, which has the same number of ejection holes formed on ring zones divided into equal areas. A solid suspended particle collection device characterized by: