JP2869714B2 - Removal method of reinforcing fibers from fiber reinforced waste calcium silicate insulation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for removing reinforcing fibers from fiber-reinforced waste calcium silicate insulation.

[0002]

2. Description of the Related Art Conventionally, among various heat insulating materials, fiber reinforced waste materials of calcium silicate heat insulating material are easy to form, and have excellent strength and heat insulating performance. In such industrial fields, it is widely used as a heat insulating material for piping, tanks, equipment and the like. But,
Insulation materials used for the above piping and tanks are removed during regular inspections and replaced with new insulation materials.
At the time of replacement, a large amount of dismantled heat insulating material comes out as waste material.

[0003]

The heat insulating material waste is treated as so-called industrial waste. In the case of a fiber reinforced calcium silicate heat insulating material, the calcium silicate is removed by removing the reinforcing fibers to make the catalyst carrier. It can be reused as high value-added materials. As a result, it is possible to increase the options of the method for reusing the waste material of the calcium silicate heat insulating material and to greatly contribute to resource saving.

As a method of separating fibers from a composite material reinforced with fibers, there is, for example, a method of separating fibers from a composite material described in Japanese Patent Publication No. Hei 6-503768.
This fiber separation treatment method is intended to recover and reuse the reinforcing fibers, and is a method of gradually pulverizing the reinforcing fibers in the composite material as little as possible and separating them by sieving. is there.

[0005] However, the above method is an effective method for adopting reinforcing fibers for the purpose of reusing the reinforcing fibers, but the residue from which the reinforcing fibers have not been separated is crushed again and sieved. Since it is necessary to repeatedly perform an operation of separating fine particles and coarse particles by separation, a method of removing the reinforcing fibers from the composite material is inefficient, and it is difficult to completely remove the reinforcing fibers. Further, in the classification by the sieving machine, since the minimum opening of the standard sieving is set to 37 μm, if the particle size of the crushed particles is smaller than that, the fiber is mixed into the fine powder side, so the fiber is removed. It cannot be applied to the classification process for the purpose of collecting the fine particles after the separation.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems. In order to recover calcium silicate contained in a fiber-reinforced calcium silicate heat insulating material waste material, the reinforcing fibers are efficiently separated and removed from the heat insulating material waste material. It is intended to provide a way to:

[0007]

As a result of various experimental studies, the present inventors have found that a waste fiber reinforced calcium silicate heat insulating material is pulverized to a 50% particle size of 30 μm or less, and then subjected to pulverization. By classifying the pulverized material into fine particles (calcium silicate) and coarse particles (reinforcement fibers) by a forced vortex classifier, it was found that the reinforcement fibers could be separated and removed efficiently. The present invention has been completed based on this finding. That is, the method for removing reinforcing fibers from waste fiber reinforced calcium silicate heat insulating material according to the present invention comprises the steps of:
After the pulverization process is performed so that the% particle size becomes 30 μm or less, the pulverized material is subjected to a classification process by a forced vortex type classifier, and the fine powder outlet side of the classifier is collected.

[0008] The forced vortex classifier used in the present invention comprises:
For example, as shown in JP-B-63-47515,
Classification is performed by centrifugal force due to rotation of the rotor in the casing and drag due to the flow of air supplied from the outside of the casing toward the center of the rotor. Is centrifugal force>
Utilizes a classifying function that establishes a drag relationship.

When performing classification using the above-mentioned forced vortex type classifier, the reason why the fiber reinforced calcium silicate insulation material is ground to a 50% particle size of 30 μm or less is because of the classification function of the forced vortex type classifier. Due to the limit of 50%
If the particle size is 30 μm or more, the yield of the particles collected from the outlet of the fine powder particles tends to be significantly reduced. Thus, according to the method of the present invention, the reinforcing fibers can be efficiently separated and removed from the fiber-reinforced calcium silicate insulation waste material.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in the flowchart of FIG.
After pulverizing with a pulverizer so that the 50% particle size becomes 14.63 μm, the pulverized material is supplied to a forced vortex classifier,
Classification was performed under the condition of the rotor of the classifier at 5000 rpm. As a result, the fine particle outlet side (calcium silicate powder) yield of the classifier was 46%, and no mixing of glass fiber powder was observed.

[0011]

FIG. 1 is a flowchart of the method of the present invention, and FIG.
FIG. 1 is a sectional view showing a schematic configuration of a forced vortex classifier used in the method of the present invention. In FIG. 2, 1 is a casing,
2 is an annular classifying chamber formed in the casing, 3 is a pulverized material supply port opened in the center of the casing, 4 is a rotating rotor in the classifying chamber, 5 is a rotating shaft, and 6 is provided on the periphery of the rotor. Classifying blades, 7 is a coarse powder outlet provided in the casing, 8 is a sorting air supply port, 9 is a fine powder passage, 10 is a spiral casing communicating with the fine powder passage, and 11 is a spiral casing. This is a fine powder outlet.

In the forced vortex type classifier having the above configuration,
The pulverized material (pulverized waste heat insulating material) supplied from the supply port 3 into the casing is rotated in the classifying chamber by the action of the rotating rotor 4 and the classifying blades 6, and the fine powder particles having a small centrifugal force are separated by a sorting wind. The fine wind from the supply port 9 is sent to the spiral casing 10 from the fine powder passage 9 and is taken out from the fine powder outlet 11, while the coarse powder having a large centrifugal force goes counter to the wind and separates the casing. It is taken out from the coarse powder outlet 7 and classified.

Next, as an embodiment of the present invention, a case will be described in which reinforcing fibers are removed from calcium silicate insulating material waste containing glass fibers as reinforcing fibers. After the calcium silicate heat insulating material containing glass fiber as a reinforcing fiber is pulverized by a pulverizer so that the 50% particle size becomes 14 to 20 μm, the pulverized material is subjected to the forced vortex type classifier (Micro separator by Hosokawa Micron Co., Ltd.). As a result, as shown in Table 1, by appropriately selecting the rotation speed of the rotor, fine particles of calcium silicate from which the reinforcing fibers were removed from the outlet of the fine particles could be obtained. In this example, the particle size was measured using a laser diffraction scattering method.

[0014]

[Table 1]

As is clear from the above Table 1, the fiber reinforced calcium silicate heat insulating waste material has a 50% particle size of 30 μm.
Calcium silicate that completely removes fibers and does not mix fibers by pulverizing so that it is as follows and supplying the pulverized material to a forced vortex type classifier and appropriately selecting the number of revolutions of the rotor of the classifier Can be recovered.

[0016]

According to the present invention, the reinforcing fibers can be efficiently separated and removed from the fiber reinforced calcium silicate insulation material waste material.

[Brief description of the drawings]

FIG. 1 is a flowchart of the method of the present invention.

FIG. 2 is a sectional view of a forced vortex type classifier.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 2 Classification chamber 3 Pulverized material supply port 4 Rotary rotor 5 Rotary shaft 6 Classification blade 7 Coarse powder discharge port 8 Sorting air supply port 9 Fine powder path 10 Spiral casing 11 Fine powder discharge port

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshishige Ishizuka 2-8-22 Kozu, Odawara City, Kanagawa Prefecture (72) Inventor Yoshihiro Yokoi 9-5-22 Togami, Toride City, Ibaraki Prefecture (72) Inventor Tomoyuki Seki Chiba 11-37, Oyumino, Midori-ku, Chiba-shi (56) References JP-A-4-114780 (JP, A) JP-A-61-197083 (JP, A) JP-A-4-180879 (JP, A) JP-A-59 −45958 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B09B 5/00 B07B 7/083 C04B 7/24

Claims (1)

(57) [Claims] 1. A fiber-reinforced waste calcium silicate insulation material is pulverized so as to have a 50% particle size of 30 μm or less, and the pulverized material is classified by a forced vortex type classifier. A method for removing reinforcing fibers from fiber-reinforced waste calcium silicate insulating material, characterized in that a grain outlet side is collected.