JPS5847518B2 - Classifier for wood chips contaminated with foreign substances - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a dry manufacturing method for fiberboard.
This invention relates to a classification device for removing foreign substances such as metal pieces and stone pieces from wood chips that are mixed in with the wood chips before the chips are inserted into a fibrillator.

For wood chips, we use the ends of logs, offcuts, plywood ears, stripped cores, etc., so we use S-shape holes driven into the ends of logs to prevent them from cracking, nails for assembling rafts, pieces of wire, etc. They often contain foreign objects such as metal fragments, shells such as barnacles that adhered to the logs when they were stored at sea, and pebbles and sand that were bitten into the surface of the logs when they were piled up at the dump.

The chips obtained by crushing wood contaminated with such foreign substances are further passed through a fibrillator to form wood fibers, and the fibers are heat-press plated with adhesive to produce fiberboard. The blades of the spinning machine may be damaged, or sparks may ignite the fibers, causing a dust explosion or fire.
Furthermore, it had the disadvantage of causing various problems such as damaging the saw blade when processing fiberboard.

By the way, there are two methods for producing fiberboard: a wet method and a dry method. In the former, wood chips are transported in water, so foreign substances with a large specific gravity are precipitated and removed, but in the dry method, wood chips are transported in water. Since the chips are blown by air current, in order to remove foreign substances, it is necessary to install a metal detector during the transport and discard chips containing metal, or to attract iron pieces with magnets placed appropriately along the transport path. has been attempted, but
The former has a poor chip yield, the latter cannot separate non-ferrous metals, and both cannot separate non-metals.However, no device has been thought of that can remove foreign substances more efficiently than from wood chips contaminated with foreign substances. do not have.

The present invention solves the problems of the prior art, and specifically aims to provide a classification device that efficiently separates foreign substances from wood chips before inserting the chips into a defibrator in a dry manufacturing method for fiberboard. It is something to do.

Embodiments of the apparatus of the present invention shown in the drawings will be described below.

Wood chips mixed with foreign matter are transported through a chip transport path 1 such as a pipe or duct by a chip transport device 2 such as a chip silo, a heel conveyor, or a screw conveyor, and are transported through a chip transport path 1 such as a pipe or duct, and are transported to the upper part of the classification device of the present invention. The chips are supplied to a vertical or inclined tubular chip fall path 3 located approximately in the middle.

Directly below the chip falling path 3, a multi-stage classification looper device 5 is installed.

In this classification louver device 5, each looper 4 is of a multi-stage type, and the classification device of the present invention is divided into a blower tower 7 and a classification tower 9.

The louver device 5 is arranged so that chips falling from the falling path 3 will definitely hit the looper 4 at the top.

Each looper 4 is inclined downward by 25 to 35 degrees θ1 from the classification tower 9 toward the blower tower 7, and the loopers 4 at each stage are parallel to each other.

Furthermore, the lower edges of each looper 4 protrude sequentially toward the lower stage, and a line connecting the lower edges of these loopers 4 forms an angle θ2 of 55° to 65° with respect to the horizontal line.

On the other hand, the lines connecting the upper edges of each looper 4 form a vertical line and are aligned in a straight line.

On the right side (in the drawing) of a line connecting the lower edges of the classification looper 5, there is formed a blowing tower 7 having a suitable shape such as an elongated cylinder or a spindle, as described above.

A suitably shaped foreign matter discharge pipe 11 is provided at the bottom of the blower tower 7 near the extended position of the line connecting the lower edges of the looper 4.

Similarly, when viewed from the lowest end of the louver at the bottom, a blower 8 and a blow pipe 18 are provided at a position further away from the foreign matter discharge pipe for generating a strong upward airflow from bottom to top in the blow chamber.

Furthermore, the loopers 4, 4 of the blow tower 7...
- A rectifying blade 6 is attached to the air passage formed by the air passage, which serves as a guide for changing the direction of the air.

Next, on the upper edge side of the classification louver, there is a classification cylinder 9 which is vertically elongated and has a cylindrical or cyclone-like shape, and has a fine powder C discharge pipe 16 at the top and a chip discharge pipe 10 at the bottom. are doing.

The fine powder discharge pipe 16 is connected to a dust collector 17 such as a Bang filter pulse air collector.

It is also possible to provide a discharge valve such as a rotary valve at the lower end of the foreign matter discharge pipe 11.

Similarly, a discharge valve such as a rotary valve may be provided at the lower end of the chip discharge pipe 10.

By providing the above-mentioned discharge valve, it is possible to adjust the amount of chips and foreign matter discharged, and at the same time, it is possible to prevent airflow from leaking from the discharge pipe.

At the lower end of the chip discharge pipe 10, a chip discharge device 1 such as a screw conveyor or a belt conveyor is installed inside.
By forming a chip hopper 12 with a built-in chip 3, the chips can be continuously transferred to the next process, such as a diester or a refiner.

Similarly, a foreign matter dumper 14 having a built-in foreign matter discharging device 15 such as a belt conveyor or screw conveyor is installed on the lower surface of the foreign matter discharge pipe 11 for transferring foreign matter to an incinerator, a foreign matter storage area, or the like.

With the above structure, the foreign matter A, the wood chips B, and the mixture of foreign matter and wood chips discharged from the lower end of the chip fall path 3 roll on the four surfaces of the classification looper and fall due to the action of gravity. .

During this falling process, wood chips with low specific gravity and high air resistance are blown up along the surface of each classification louver, blown out from the upper end of the classification louver into the classification tower 9, and fall inside the classification tower 9. will be collected.

Since the foreign matter A has a high specific gravity and low air resistance, the foreign matter A successively falls down the lower edge of the louver and is introduced into the foreign matter discharge pipe 11.

When the L-chip from which the foreign matter has not been completely separated falls from the lower edge of the upper looper 4 onto the lower looper 4, the foreign matter is separated from the chip by the impact force at the time of the fall.

Thereafter, since the chips have a low specific gravity, they are blown up by the introduced air along the surface of the looper 4 and enter the classification tower 9.

Since the foreign matter has a high specific gravity, it falls into the blow tower γ from the lower edge along the four surfaces of the looper.

Then, it descends inside the blow tower γ against the upward force of the introduced air, and is discharged from the foreign matter discharge pipe 11.

The inclination angle θ1 of the classification looper 4 with respect to the horizontal line is 25
As a result of the test, the inclination angle θ2 of the line connecting the lower edge of the looper 4 with respect to the horizontal line was 55° to 65°. As a result, wood chisop B, foreign matter A, and a mixture of chips and foreign matter rolled on the looper 4 without stagnation. The contact resistance with the louver surface was too small to cause the objects to fall, but instead to roll while constantly contacting each other on the louver surface and exerting force, this was a favorable result for falling down at a speed suitable for classification.

Furthermore, the wind speed inside the blow tower 7 and the wind speed along the louver surface 4 vary depending on conditions such as the distance between the upper and lower louvers, the specific gravity of the chip, the size, etc., but in short, the wind speed along the louver surface 4,
The blower 8 rectifies the wind speed in such a range that chips with low specific gravity and high air resistance are blown up, but foreign objects with high specific gravity and low air resistance fall against the wind and fall on the louver surface due to the action of gravity. This can be easily achieved by adjusting the blades 6 appropriately.

Since the present invention has the above-described structure, it is possible to efficiently separate foreign objects and wood chips by combining the functions of separating foreign objects by impact and air sorting.

In addition, damage to the defibrating machine blades during fiberboard manufacturing,
It can prevent various problems such as fiber fires and saw blade breakage during fiberboard processing, and is particularly suitable for the dry fiberboard industry.

Note that the present invention has the advantage that the foreign substances separated are not limited to magnetic substances such as iron.

[Brief explanation of drawings]

FIG. 1: An explanatory diagram of one embodiment of the present invention. Explanation of symbols, 1...Chip transport path, 2...
...Chip transport device, 3...Chip falling path, 4
...Individual louver, 5...Classification louver device, 6...Blower blade, 7...Blower tower, 8...Blower , 9... Classification tower,
10... Chip discharge pipe, 11... Foreign matter discharge pipe, 12... Chip hocher-13...
...Chip discharge device, 14... Foreign matter hopper,
15... Foreign matter discharge device, 16... Fine powder discharge pipe, 17... Dust collector, 18...
intake pipe.

Claims (1)

[Claims] 1. A chip fall path 1 at the top of a hollow box body shaped like an inverted heart.
A looper 4 is installed in multiple stages directly below the fall path 1, and the looper 4 is divided into a classification tower 9 and a blower tower 7 on the left and right. A discharge pipe 16 is connected, and the blow tower 7 has a chip discharge pipe 10 at the bottom, and the blow tower 7 has a foreign matter discharge pipe 11 at the bottom, and air from the intake pipe 18 is introduced into the blow tower 7 below the bottom. A blower 8 is built in, and the looper 4 is inclined downward from the classification tower 9 toward the blower tower 7, and the lower edge of each looper 4 on the side of the blower tower 7 protrudes sequentially toward the lower stage. A device for classifying wood chips contaminated with foreign matter, characterized by: 2 Each stage of loopers 4, 4... in the blower tower T.
2. The device according to claim 1, wherein an air passage having the shape of . 3 The inclination angle θ1 of the looper 4 is 25 to 35 degrees, and the inclination angle θ2 of the line connecting the lower edges of the looper 4 is 55 to 65 degrees.
The device according to claim 1.