JPS5830842B2 - Classifier in air transport pipes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a classification device for a pneumatic transport pipe for powdered materials, for example, a pneumatic transport pipe connecting a dryer and a cyclone.

In an air transport pipe, when the flow direction is to be changed from a horizontal flow to a vertical or nearly upward direction, the present invention provides an extremely small difference in specific gravity in the curved pipe section.
This was done by focusing on the phenomenon that powdery particles become resistant to adhesion due to differences in particle size or due to a slight excess of moisture.

In the case of irregular drying conditions, variations in particle size, or contamination of foreign substances with different specific gravity, undesirable particle size or specific gravity may occur inside the flash dryer or in the discharge section of the drying material such as a rotary cylindrical dryer. It would be advantageous if the difference could be removed at the time of passing through the transport pipe, since no equipment would be required, especially for the sieving part.

The present invention has been invented in view of the above points, and its gist is to discharge classified excluded materials at the bent bottom of an air transport pipe that changes the flow direction from the horizontal direction to the upward direction. A hole is drilled, and a large number of ejection ports for generating outer circumferential airflow are formed on the outer circumferential side of the refractive index radius above the discharge hole, and air supply pipes that can freely adjust the amount of ejection are connected to the large number of ejection holes. The present invention relates to a classification device for a pneumatic transport pipe, characterized in that:

That is, the present invention classifies materials that were conventionally classified separately from the pneumatic transport pipe by installing a classifier in the pre- or post-process of the pneumatic transport process, but simultaneously during transport within the pneumatic transport pipe. This is what I did to get it.

An embodiment of the present invention will be described below based on the drawings.
In the figure, a is an air transport pipe, and this air transport pipe a has a rotating cylinder connected to its tip and a cyclone C connected to its rear, and the raw material is connected to the rotating cylinder via a feeder e from a raw material supply line d. and a hot air generating furnace f
The structure is such that hot air is introduced from the

Therefore, the raw material supplied into the rotating cylinder is heated to the hot air generating furnace f
The air transport pipe a is dried by hot air blown from the air transport pipe a.
The air passes through the inside of the cyclone C and is discharged from the lower part of the cyclone C, and the air accompanying the flow is discharged to the outside from the exhaust pipe g.

A suction blower for generating airflow is installed at the upper part of the air transport pipe a to transport the powder and granules by air.

The air transport pipe a is formed to have a rectangular cross section, and has an upwardly inclined bent part a2 extending from its horizontal part a1, and a vertical part a3 connected to this bent part a2. , a discharge hole 1 having a circular cross section is opened in the lower part of the bent part a2,
Further, the upper inclined bottom surface is provided with a large number of jet holes 2, 2, 2, .

Guide vanes 3, 3, .
A cover plate 4 is attached to the outer surface of the bent portion a2 provided with the curved portion a2 so that a space 5 is created between the outer surface and the outer surface, and an air supply pipe 6 whose amount of jetting can be freely adjusted is provided in the space 5. Install consecutively.

The illustrated air supply pipe 6 has an orifice 7 therein for adjusting the flow rate.
is installed to adjust the amount of ejection.

A discharge pipe 8 is connected to the discharge hole 1, and this discharge pipe 8
Air seal dampers 9, 9 are installed in upper and lower two stages in a manner that can be opened and closed freely, and by opening and closing these dampers 9, 9, particulate matter is continuously or intermittently discharged from the inside of the discharge tube 8 to the outside. .

To explain the classification method below, the powder and granular material, which is the material to be dried after passing through the rotating cylinder, is moved from the horizontal part a1 of the air transport pipe a to the bent part a2 by the flowing air generated by the suction force of the suction blower. The vertical portion a3I is sequentially transported, but particles with large diameters or large specific gravity that cannot be carried by this air flow A are diverted through the bottom of the air transport pipe a and stagnate in the discharge hole 1. The powder and granules that are carried along with the air current A also tend to settle to the bottom of the bending part a2 due to the centrifugal force caused by the change in the flow direction and their own weight, and the heavier granules and the like stagnate in the iron part. In addition, powder and granules with a high water content adhere to iron parts and impede the pneumatic transport function.

Therefore, in such a case, air at a predetermined pressure is blown from the air pipe 6 and ejected from each of the ejection holes 2, 2, . . . to generate an outer circumferential airflow port.

In this way, particles that stick to the bottom of the bent part a2 and remain stagnant are floated by the outer airflow port, those that get on the airflow port are transported through the outer airflow port, and those that cannot get on the airflow port are diverted. Meanwhile, it falls into the discharge hole 1.

The powder particles that have fallen or stagnated in the discharge hole 1 are discharged from the discharge tube 8 to the outside.

The classification of the powder and granules flowing through the air transport pipe a is performed by adjusting the amount of air sent from the air pipe 6. In other words, depending on the amount of air sent, the amount of air sent through the outer circumferential air flow port increases or decreases. It is from.

Since the present invention is constructed as described above, the outer circumferential airflow ejected from a large number of ejection holes causes the powder and granules to be removed from the bottom of the bent part where the particles to be transported tend to stagnate or adhere. It is resistant to adhesion, is removed without stagnation, and does not become an obstacle to pneumatic transport, and this peripheral airflow simultaneously classifies the transported material and discharges a part of it to the outside from the discharge hole, so the classifier can be There is no need to install it separately from the transport pipe.

Therefore, the intended purpose can be achieved.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a front view showing the state of use, FIG. 2 being a longitudinal sectional view, and FIG. 3 being a sectional view taken along line X--X. In the figure, a is the air transport pipe, a2 is the bent part, 1 is the discharge hole,
2, 2, . . . indicate jet ports, and 6 indicates an air pipe, respectively.

Claims (1)

[Claims] 1 At the bent bottom of the air transport pipe that changes the flow direction upward from the horizontal direction, a discharge hole for discharging the classified waste is bored, and at the same time, an outer circumferential air flow is formed above the discharge hole on the outer circumferential side of the radius of curvature. 1. A classification device for an air transport pipe, characterized in that a large number of ejection ports for generation are opened, and an air supply pipe that can freely adjust the amount of ejection is connected to the large number of ejection ports.