SU76440A1 - The method of dehairing and degreasing skins namazju - Google Patents

Description

With the existing de-skinning method of skinning with spreads, the effect of the treatment depends substantially on the moisture content of the skin. In case of increased moisture content of dehairing hides (for example, 65-70%), their swelling occurs during namazi; and face tightening; the duration of the laying of the smeared skins comes to 12-16 hours.

To reduce the moisture content of the raw oil before it is usually done, a two-hour pre-bedding is usually performed or the skins are dehydrated by centrifugation. However, these measures do not reach the goal.

With the existing concentration of NazS in salami from 40 to 80 and a treatment temperature of 30-35 ° C, significant hydrolysis of protein substances occurs.

To eliminate these drawbacks, it was proposed to replace lime with kaolin, add alkali or sulphites to Namaz, and also add soda or soda to the sludge before soda. All of these proposals are not applied to industry, as the ratios between the components in spreads were optimal.

For a rationally constructed technique, the ratio of OH and

SH in spreading slurry should be equal to 2: 1.

The analysis of sulphide ash pits shows that SH ions remain in the solution in an amount of at least 80% of the initial amount, and that the OH ions are completely consumed. This shows that the participation of SH in namazi can be reduced several times, and the content of OH should be increased. To avoid in this case the possibility of swelling of the skin, salt should be added to the namaz, which acts as a dehydrator on the skin of the skin. Introduced B namaz alkaline gruel makes the saponification of fat, and therefore it is very difficult part of the operation of degreasing - the penetration of a degreasing agent into the thickness of the raw material - occurs reliably and quickly.

Example. After the usual soaking and shredding, a namaz of the following composition is given: 15-20 sodium sulphide, 7.5-10 g / D1 sodium hydroxide or 10-15 g1l of soda ash and 50-100 sodium sulphite.

Lime is added to 1 liter of such a mixture to the normal density of the namazi. With such a namaz, the wool disappears in 2-3 hours, and even on the edges of the coat,

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very clean and intact. The epidermis is only partially destroyed and comes off with a film, which indicates an extremely mild effect of the mixture on the hair follicles and other keratna formations.

Then the wool is rolled, after which the pelt is loaded into a low-speed drum (3-5 rpm) or a vat with a solution of the following composition: 50 g / l of boiled salt or glauber's salt and 10 g / u of sulphite, where it is treated within 2-4 hours at LCD and at a temperature of 23-25 ° C.

After making the hide, the scaffolds are cleaned on the machine, washed with running water in the launch and served, as usual, for dehazolis and subsequent operations, with pickling or treatment in a salt bath for at least 8 hours.

In the salt bath, water slowly penetrates the mole, accompanied by emulsifying the fat and swelling the mole, due to the alkali inside it. Simultaneously swelling

Extrusion of fat emlsii into the external solution occurs. Then the nonalignan hide is fed to the fleshing machine, where abundant secretion of gneist and fat occurs, as well as flesh.

The described method is primarily useful for the production of sheepskins, but can be used "for the production of other types of raw materials.

Subject invention

The method of dehairing and degreasing the skins with namaz using a gruel, which includes caustic soda or soda ash, characterized in that the cheek is treated with a gruel containing about 15-20 g / l of sodium sulfate, with the addition of sodium sulfite, after removal of the hair saline, undergo surgery, face cleaning, rinsing, peeling, and then treated as usual with lengthening the duration of a pickle or salt bath for up to 8 hours.