Pages 134–138
Abstract
Research summary supplied by the authors
The Federal Law “On the Protection of Lake Baikal” aims to comprehensively protect its ecosystem and promote the sustainable development of adjacent territories. Strict requirements for the quality of discharged wastewater prevent the processing of leather and fur raw materials in the central, buffer, and atmospheric zones of the specially protected area of Lake Baikal. It is known that industrial processing of raw hides and skins requires large volumes of water, which creates challenges associated with treating significant quantities of toxic wastewater. This prompted us to develop new raw hide processing methods that virtually eliminate dyes, organic tanning agents, and fatliquoring agents from wastewater, significantly reduce chrome tanning agent consumption (by 32%), and shorten the production cycle by 4-5 times. This was made possible by new methods of introducing chemicals into the dermis, ensuring that the chemicals are completely absorbed into the semi-finished product, eliminating wastewater. The aim of this work is to find solutions to environmental problems in leather production by implement- ing an original process flow diagram and using new materials. This work proposes a new, original raw hide processing flow diagram in which dyeing, retanning, and filling are performed before the main tanning and fatliquoring with chromium compounds. A mechanism for intensive mass transfer of the materials used into the dermis has been developed. At the same time, the number of technological processes is reduced from 10 to 6, and their duration, including pickling, tanning, dyeing, retanning, filling, and fatliquoring, is reduced from 20-27 to 4-5 hours. The quality of the finished leather complies with the standards of Russian Federation Standard 939-2021 “Leather for Shoe Uppers. Technical Conditions.” The proposed approach is also applicable to the tanning of other types of leather, such as clothing leather.