The invention discloses a leather making bio-
pretreatment method. By using a
biotechnology to replace or partly replace a chemical method and utilizing compound
enzyme preparations including
lipase and
protease, the method strengthens processes of soaking and
degreasing, accelerates dispersion of collagen fibers, optimizes the
enzyme bating process, shortens the
treatment time and reduces the consumption of water and the use of a chemical additive. Compared with the traditional leather-making technology, the leather making bio-
pretreatment method can accelerate the soaking process and the
fiber dispersion process, shorten the
process time by 6-12h, realize
water saving by about 30 percent and COD (
Chemical Oxygen Demand) emission reduction by 20-40 percent, lower the dosage of protosulphide by 40-50 percent and the like. In the invention, on the basis of lowering the consumption of the protosulphide by using a hair-saving method, an environmental friendly auxiliary liming agent which is prepared by utilizing the
biotechnology and a physicochemistry principle can completely consume residual
sulfide in waste liquid to enable unhairing waste liquid and limed pelts not to contain the
sulfide and completely eliminate
pollution of the
sulfide; therefore, the invention has the advantages of simple operation and low cost without influencing the product quality. In addition, in the whole pretreatment process, the biological
enzyme preparation is considered to be utilized to efficiently and harmlessly remove components on
animal skin unrelated to leather making.