Leather waste resource recycling value

Leather waste, usually refers to the first ingredient for the references on construction waste. Leather waste variety is more, according to the history can be divided into the leather produce attack dereliction, leather products produced in the onset of cut out excess stock and recycled leather products; According to the leather waste composition and the difficulty of the comprehensive use of points: 1, do not contain chromium leather waste Such as fur, grey leather crafty and tanning wastes, etc., because of the simple component, using simple comparison. 2, the waste containing chromium leather Such as blue wet shaving leather scraps, splitting and circle edge waste, because is rich in chromium salt, use comparison difficult. 3, containing dye leather waste Such as dry cutting of leather and side of waste materials, leather cutting ring, etc., because in addition to rich in chromium salt, also including dyes, fatliquoring agent and retanning agent, such as chemical materials, one of the most difficult to use. The use of leather waste, is an old topic. In 1928, the italians will first of all, the waste containing chromium leather for leather material. But because of chrome damage, using the restraint of must. Current, first using the field is still on its produce non-woven fiber features, do the basal data, such as the artificial leather, or mixed with other fiber composite materials, during which the chromium and didn’t get reasonable use, commodity value is not high, also has a some used as fertilizer and feed etc. As always, because they can’t get some reasonable use and had to be buried. For the use of reasonable and effective path, research and development of high value-added products, has become a important issue in leather waste to use. 1, original skin developing feed Raw skin after high-pressure, cooking, sterilization process, can produce a brown yellow meat and bone meal, meat and bone meal preparation in such a pet feed and feed compared before, not only high nutrient value, economic benefit is very big also. 2, organic fertilizer, Leather waste guess “nitrogen” that are rich in a lot of, can be produced by calcining agricultural fertilizer, in order to satisfied with crop yield and output value of the progress of wheat and rice. 3, hair use In leather production, to recover the use of waste wool top contains sheep wool and goats’ hair, in addition to the direct back, MAO’s development using discussion includes: MAO’s degradation, degradation products of separation and purification, etc., it can be used in the following aspects: biological fermentation and soil conditioner, chemical degradation of preparation of protein polypeptide, etc. 4, meat residue using The material skin after flooding to the meat of the proceeds of the flesh slag is recovered grease can’t ignore the material. To meat the after wash boil them in the meat, fat floating on the liquid at the moment, oil gathering up from liquid surface, the recovery of oil saponification value in 190-210, usually can be used to produce high-grade oil, glycerin, etc., in the leather industry will also often the grease for sulfate or after the sulfurous acid used in leather fatliquoring. Don’t waste containing chromium leather for not rich in chromium salt harmful substances, such as simple through pretreatment and hydrolysis to obtain high purity of collagen protein products, such as edible gelatin, edible collagen protein, collagen regeneration of skin, medical and cosmetic use collagen, etc. With a pet dog breeding, dog bite plastic commodity market demand is more and more big. This kind of leather wastes through regeneration preparation into area and thickness of controllable regeneration collagen skin, do not increase the adhesive and other harmful substances. And rubber products production is a dog lay cut waste can also be used for preparation of renewable dog bit the rubber from the ground up, not only can be extended dog bite rubber goods produced material size, also can produce a big drop in cost. 1, the waste containing chromium leather hydrolysis mechanism and method for collagen Waste containing chromium leather under the condition of strong hydrolyzed collagen polypeptide chain amide linkage some cracking and degradation, which constitute a water-soluble collagen. Waste containing chromium leather hydrolyzed mechanism using primary has two aspects, the progress of the waste containing chromium leather adhesive rate and decline of chromium content in the collagen. 2, loop method to obtain the waste containing chromium leather guess collagen protein Resulting from the waste containing chromium leather by hydrolysis chrome sludge, chromium mud filtrate is obtained by secondary hydrolysis 1 again and chrome cake, chrome cake wash filtrate after 2, merge the filtrate 1 and 2 for collagen hydrolysate, the hydrolysate instead of water recycling is used in the waste containing chromium leather hydrolyzed, a high concentration of collagen solution can be obtained. 3, series collagen matrix leather chemical materials (1) c dilute acid monomers grafting modified collagen preparation retanning agent Using such a complex tanning agent in leather-making, can show the progress of leather goods raising effect and elastic. Plump and soft feel, leather thickening reached 20%, area of shortening rate lower than 10%. (2) amino resin modified collagen protein filling agent Collagen protein filling agent used in leather making process, have significant choose filling effect. And because the filler is collagen of gender structure, retanning does not constitute a “lost color” representation of leather. Together, feel the natural soft, no plastic feeling. (3) acrylic resin modified collagen finish This compared with pure acrylic resin finishing agent, finishing agent modified collagen finishing agent has excellent covering effect of disability, feel comfortable, without a sense of plastic and good solvent resistance function. (4) polyurethane modified collagen finishing agent Finishing using results show that the polyurethane is introduced in the collagen molecules structure can greatly progress film-forming function of collagen, and feel comfortable with no plastic. (5) the use of chromium residue preparation of chrome tanning agent The test results show that when the dosage of dichromate is more than four times of chromium content in chromium residue, the obtained chrome tanning agent and pure dichromate reduction of chrome tanning agent no significant different. 4, collagen composite fiber Protein fiber is the natural protein as main material, through the modification and blending with other data, made must concentration and viscosity of the solution, and then out of the nozzle hole kneading into the liquid solidification form filaments, through follow-up, stretching after processing can get boring can be used for textile fibers. Protein fiber with real silk luster, feel soft and comfortable, has excellent moisture absorption function, and the dyeing function is superior. 1, leather dyeing filling agent Use dyeing leather leather waste filling agent, has good filling effect. Dyeing filler amino resin modified collagen protein, it contains dissolved waste guess the retanning agent, collagen protein is associated with complex tanning agent has excellent filling effect. Color filler in the dye can have the effect of dyeing, and falling produce leather dyes dosage of 10-30%, in the process of save production cost. 2, dyeing superfine damage and use leather waste Leather waste is ductile material, by coarse damage and embrittlement after pretreatment can progress can damage the function. For superfine damage, superfine powder leather can be obtained. Mix with pu leather powder slurry, moving in synthetic leather and split leather wet membrane, the composition is in the introduction of synthetic leather, leather can be progress of wet synthetic leather and split leather shift membrane layer wet wet absorption function and feel. China leather industry attack every year a lot of abandoned references data, as a high input, low output of the traditional industry, leather industry in the process of its yield, 30% of the material into a waste after all. In recent years, China’s annual production of about 1.4 million tonnes of leather wastes, in together to the environmental pollution, the intervening collagen and chromium trioxide also lost a lot, constitutes the infinity of biomass capital. In leather waste down the large tailings, some are leather material, during which more than 80% of collagen, not only the rich nutrient source of protein and amino acid, is also excellent functional polymer materials together. Because of its unique biological characteristics, leather waste in medicine, food products, functional health food, agriculture and so on more than one category has a wide using prospect. Back and full use of the solid waste and waste leather products not only can provide a lot of new materials industry, reduce damage to the ecological environment, also is helpful for leather industry together for very long time.