Ways to reduce the environmental impact in wet end were presented by MK in technical meeting

The programming of XIX National Meeting of the Leather Industry Technicians and Chemists, promoted by ABQTIC – Brazilian Association of Leather Industry Technicians and Chemists, carried out in Franca, counted on the participation of MK. The Manager of research and development, Rejane Paiva, presented the work “Reduction of environmental impact in wet end”, developed by the MK Technical Team. The work, aligned to the theme of the meeting, “innovations in leather processing”, approached the problem of high levels of waste substances contained in the water of tannery process and that many times represent difficulties for the companies to meet the limits of emission stipulated by the environmental legislation. The work showed the technologies developed by MK to obtain products with a greater exhaustion and fixation to the leather fibers and the application of these processes that aim to reduce Nitrogen and COD in wet end baths. According to Rejane Paiva, “to ensure the best fixation and thereafter a greater exhaustion of the bath products, the products used on the several steps of wet end contemplate the insertion of more reactive functional groups, capable of chemically bind to the leather and not let substances free in the process waste water. Furthermore, the use of nitrogen products was eliminated and the process was optimized in a way to generate the lowest possible volume of liquid effluent." In the process proposed by MK, the neutralization, pre-fatliquoring and chromium retanning are carried out in the same bath, which also receives the retanning agents, dyers and fatliquors. All this work is only possible due to the use of products of high stability. Only the remount is performed in a new bath, which means that the process is carried out with only 40% of the water that would be necessary in a traditional process, resulting in only 30% of the traditionally generated effluent. This represents a great advantage in both environmental and economic aspect, as the water is a resource more and more expensive and scarce. However, regarding the COD, with the process proposed, a reduction of more than 75% is obtained in the effluent load, result of the greater fixation of the products and consequent exhaustion of the baths. Regarding the Nitrogen, the presence of this element is almost eliminated in the residual baths.