SU1685721A1 - Method of processing worn tyres with metal cord - Google Patents

Description

(21) 4700813/05 (22) 06/05/89 (46) 10/23/91. Bul Ne39

(71) All-Union Research and Design Institute for Secondary Ferrous Metals

(72) V.I.Mes c, A.V. Kutuzov, V.M. Stefan and O. Evstigneeva (53) 678.059.3 (088.8)

(56) US Patent

No. 3905556, cl. 241-24, published. 1975.

U.S. Patent

N 4113186, class 241-24, published. 1978. (54) METHOD OF PROCESSING EXTENDED PAPS WITH METALLIC CARD

(57) The invention relates to the processing of worn tires with steel cord and can be used in regenerator plants and scrap processing enterprises. The goal is high-quality separation of the steel cord from rubber and its complete extraction. To this end, after the last stage of grinding and magnetic separation, the steel cord with rubber and textile residues is subjected to firing. Moreover, first, the calcination was carried out in air with heating, up to 500-700 ° C, and then without air supply. After firing, the steel cord is subjected to tempering, then passed through rollers, magnetic separation and stacked. 1 hp ff, 1 ill.

The invention relates to the processing of worn tires with steel cord and can be used in regenerator plants and lomoprocessing enterprises.

The purpose of the invention is the qualitative separation of the steel cord from rubber and its complete removal.

The drawing shows a diagram of the method of processing.

The method of processing worn tires with metal cord includes a stepwise change of tires: first crush the tire into pieces of 150-300 mm in a rotary crusher 1 with a rotating drum, on which knives are attached in a checkerboard pattern, and with a fixed plate with cutouts for passing through knives, then on a few rolls 2, then using

Sieve 3 with a mesh size of 1.5-3 mm pieces are sorted, to separate the metal part from the non-metal crumb rubber that has passed through the sieve using pendant electromagnets (not shown) are subjected to magnetic separation. Tire pieces that did not pass through sieves 3 are also subjected to magnetic separation using an electromagnetic separator 4, and the residue is returned to the first rollers 2 and subjected to repeated grinding.

After the last stage of grinding and magnetic separation, the metal cord with rubber and textile residues is subjected to roasting, with the roasting first carried out in air to 500-700 ° C and then without air supply. The firing is carried out in the furnace 5 of firing shaft type.

In order to accelerate the burning of rubber, the first firing period is carried out at OO 00

ate VJ y

medium with an air excess factor of 1.7-2.5. When the residual rubber content reaches 10–20% (by weight of the total rubber content in the original steel cord scrap) and when t reaches 500–700 ° C, the burner is turned off, the air supply to the furnace is stopped, thereby creating a reducing atmosphere.

The firing temperature of less than 500 ° C is impractical because the percentage of residual rubber is high, i.e. there is no complete separation of the rubber from the metal cord. The firing temperature above 700 ° C is impractical because the oxidation of scrap steel cord increases.

In this process, metal oxidation is minimized. In this case, only resinous and volatile substances are predominantly burned, and carbon is mainly stored in a solid form, in the form of an ash-coke residue (up to 80% by weight of the residue).

In order to improve the quality of the packages obtained from the steel cord by cleaning from the ash-coke residue and metal oxides, the steel cord after firing is released in a heat-insulated box 6. Then it is passed through rollers 7 to grind the ash-coke residue and clean the metal surface from it, and after subjected to magnetic separation using electromagnets 8 and palletized in a packaged press 9 into packages 10, which can be used as a metal mixture for steelmaking.

At normal specific pressing pressures (200-250 kg / cm2), the density of the packages is 1

ssg

five

from the non-thermally annealed steel cord, is 900 1100 kg / m, after thermal annealing, 2800-3300 kg / m3.

Thus, bags of metal cord scrap subjected to thermal annealing allow an increase in the bulk density of scrap in the load tanks of steelmaking units.

The advantage of the proposed method of processing worn tires is the complete extraction and better separation of the steel cord from rubber, as well as higher quality packages obtained from scrap metal cord.

Claims (2)

1. A method for processing worn tires with a metal cord, including step-by-step grinding of tires, sorting and magnetic separation, is about the fact that, in order to properly separate the steel cord from rubber and its complete extraction, after the last grinding stage and magnetic Separation of the steel cord with rubber and textile remains is subjected to firing, and the firing is first carried out in air with heating to 500-700 ° C, and then without air supply. 2. A method according to claim 1, characterized in that, in order to ensure the production of high-quality packages of steel cord due to its removal from the ash-coke residue and metal oxides, the steel cord after firing is subjected to tempering, passed through rollers and, after additional magnetic separation, is palletized. P