SU1152962A1 - Method of primary processing of leather raw material - Google Patents

Abstract

1. METHOD OF PRIMARY TREATMENT OF LEATHER RAW MATERIALS, including clearing it from heap, cleaning, canning with a dry salted mixture of sodium chloride and an antiseptic, characterized in that, in order to increase the yield of skin on the area and reduce the consumption of chemicals during canning, as an antiseptic Chloramine B is used at a ratio of mixture components, wt.%: Sodium chloride 72-91 Chloramine B9-28 2. The method according to claim 1 is also distinguished by the fact that the flow rate of the mixture of sodium chloride and chloramine B is 6% by weight of the steam sf. (L

Description

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The invention relates to the primary processing of raw hides and can be used in mills and hides. Known compositions for the preservation of tanning leather containing sodium fluoride sodium 1J, sodium tetraborate and sodium chlorite 2j, chloramine B, and soda 3 are known. However, during the processing of raw materials with these compositions, its shelf life (6 days) is insufficient for carrying out the transportation, sorting and packing of production batches. In addition, when using these compounds containing 2, A-3% sodium fluoride fluoride, 2% sodium chloride, 15% chloramine B (based on the weight of the fresh raw material), a large amount of fluorine and chlorine, respectively, is highly contaminated. environment and thereby worsen the working conditions. In this case, NaCJO and ClOj are hazardous substances. Closest to the invention is the preservation of the raw material containing 40-45% sodium chloride by weight of the fresh steam and 1.5% sodium fluoride by weight of sodium chloride 4. The disadvantage of this composition is that the high consumption of salt leads to the pollution of wastewater. When canning, there is a significant change in the structure of the dermis, a large loss of moisture, a reduction in the size of the skirt, which is not fully restored during technological processes. The purpose of the invention is to increase the yield of skins by area and reduce the consumption of chemicals during conservation. The goal is achieved by using chloramine B as an antiseptic according to the method of primary processing of raw leather in the following ratio of mixture components, wt.%: Sodium chloride 72-91 Chloramine B 9-28 The consumption of a mixture of sodium chloride and chloramine B is 6% of the mass of the fresh raw material. Example 1. Corners removed from carcass, skins, cleaned and treated with a mixture at a rate of 6% of the mass of the parietal (treatment carried out in a drum or sprinkling), Composition, wt.%: Chloride rub 91 Chloramine B 9 After processing, the skins are put in a pile. The shelf life of the leather raw material at 18-20 C for 13 days. Example 2. The skins removed from the carcass are cleaned from pile up, the scum, treated and treated with the mixture at a rate of 6% of the mass of the paired (treatment is carried out in a drum or sprinkling). The composition of the mixture, wt.%: Sodium chloride 72 Chloramine B 28 After treatment, the skins are put in a pile. The shelf life of the leather raw material at 18-20s 22 days. The use of the proposed composition makes it possible to reduce the consumption of sodium chloride by 7.3–11.3 times, thereby reducing the pollution of wastewater, improving working conditions, and increasing the surface area of the leather. The consumption of a mixture of sodium chloride and antiseptic when salting vrastil by a known method is 40-45% by weight of the pair of raw materials. When salting sodium chloride in solution, it dissolves, gradually diffuses into the thickness of the dermis and removes moisture as it penetrates and partially interfiber. In the brine formed during the first hours of salting, the concentration of sodium chloride reaches 30%, and that of soluble substances 45%. B normally salted skin moisture content 4547%, sodium chloride based on the weight of the skin with wool. Such a loss of moisture and interstitial substances condenses the structure of the skin, in subsequent processes it is not fully restored and leads to a decrease in area yield. In the proposed method of primary processing of leather tanning, the salt consumption is 4-5.5% of the mass of fresh raw material when salting is spread, no concentrated salt solution is formed, the raw material is not dehydrated (moisture content is 60-61%), and there is no loss of interfiber substances. e. leather raw material retains moisture, and other paired properties. In this case, the main preservative effect is not sodium chloride,

and chloramine B. Sodium chloride is used as an additive, the main purpose of which is to evenly distribute chloramine B on a flattened skin. The structure of the tannery of short-term preservation remains unchanged and this leads to an increase in area yield.

Table 1 presents the yield data on the area of the semifinished product at various stages of processing.

Table 1

to change the mechanical operations (layout, pulling) according to the production test data, the area yield increases to 7.1%. The obtained technical and economic indicators of production tests are given in Table 2.

table 2

Yield,% of the area of processing of fresh raw materials

According to the proposed method

90.8 78.9 93.4 As can be seen from Table 1, after the hides are mixed with a mixture of sodium chloride and chloramine B at a flow rate of 6% by weight of the raw material, the area yield is 11.9% higher than the known method of processing . At the same time, in skins treated by the proposed method, the area yield after 2-hour rinsing is 1.3% higher than that on skins treated by the known method, after 10-hour soaking and washing. After tanning and suppressing, the area yield of the hides treated with the product in the method is increased by 2.2%. It should be noted that the experiment did not use mechanical operations for processing the semi-finished product. If at 29, 41

27.15

Average area of one skin,, 06

346.42

Consumption on 100 m finished

783.73 products, kg 921.77

Consumption of raw materials according to the norms per 100 m of finished product 856, 17

839.50%, kg Grade of finished products,% Economy of materials, rubles / ton of raw materials Savings of wages, rubles / ton of raw materials From Table 2 it can be seen that the latch of chrome skins from the raw leather processed by the proposed method is economically beneficial , since the technological process is reduced {non-casting), the consumption of water, chemical materials and labor is reduced (saving 1,037 r / t of raw materials), the output of leather by area increases, Compared with the basic method, et sakono S11529626

chemical processing materials 7.3-11.3 times the processing was carried out without techno to increase the area yield up to 4-5% of logical difficulties, it turned out The substances used are widely used, save labor costs, do not work in terms of industry, are cheap, have not been specially equipped . Preparation of the mixture and Spo-5

Claims (2)

, 1. A METHOD FOR PRIMARY TREATMENT OF LEATHER RAW MATERIALS, including cleaning it from bulk, dressing, preserving with dry salting with a mixture of sodium chloride and an antiseptic, characterized in that, in order to increase the skin yield in area and reduce the consumption of chemical materials during canning, chloramine is used as an antiseptic B with the ratio of the components of the mixture, May 2: Sodium chloride 72-91 Chloramine B 9-28 2. The method according to π.1, characterized in that the flow rate of the mixture of sodium chloride and chloramine B is 62 of the mass of the pair of raw materials.