Sheepskin leather making process with infinite cycling of waste liquid for liming (or restoring ash alkalinity)

Abstract

The invention provides a sheepskin leather making process with infinite cycling of waste liquid for liming (or restoring ash alkalinity). The invention has the following characteristics: infinite recycling of all the waste liquid is realized, a liming effect is better than that of a conventional process, usage amount of lime and other liming materials is substantially reduced, lime is saved by 50 to 100%, and other related materials are saved by 40 to 60%.

Description

technical field [0001] The invention belongs to the green recycling process of making full use of raw materials and reducing pollution discharge in the technical field of leather production. Herein, a tanning process for ash-free or less ash-recycled waste liquid for indefinite recycling of sheepskin for liming is introduced. Background technique [0002] Today, China has become a world-recognized leather producing country, but the rapid development of the leather industry has also caused serious environmental pollution, waste of resources and ecological damage. Liming waste liquid contains grease and its decomposition products, lime, liming agent, S 2- 、Na + , Ca 2+ , protein and its decomposition products, etc. Among them, in general, the residual lime in the waste liquid is usually 37%-55% of the initial amount, and the residual Na in the waste liquid 2 The S content is also very high. If the waste ash liquid is discharged arbitrarily, it will not only cause great poll...

AI Technical Summary

Problems solved by technology

[0002] Today, China has become a world-recognized leather producing country, but the rapid development of the leather industry has also caused serious environmental pollution, waste of resources and ecological damage

Liming waste liquid contains grease and its decomposition products, lime, liming agent, S 2- 、Na + , Ca 2+ , protein and its decomposition products, etc. Among them, in general, the residual lime in the waste liquid is usually 37%-55% of the initial amount, and the residual Na in the waste liquid 2 The S content is also very high. If the waste ash liquid is discharged randomly, it will not only cause great pollution to the environment, but also cause a great waste of resources.

[0003] At present, domestic and foreign methods of treating waste ash liquid mainly include: chemical reduction method, electrolysis method, membrane separation method, adsorption method, ion exchange method, biological method, etc., but the operation process is often costly, low in efficiency, and poor in effect. Unable to achieve the real purpose of pollution control