Processing system for changing chrome tanning wastewater into resource and processing technique thereof

Abstract

The invention provides a processing system for changing chrome tanning wastewater into a resource and a processing technique thereof. The invention relates to a processing method for the chrome tanning wastewater and provides the processing system and the processing technique for changing the chrome tanning wastewater into the resource at normal temperature and pressure with low processing cost and high recycling utilization ratio. The processing system comprises a grating filter pre-settling device, a chemical reaction settling pond, a pressure filter, an acid leaching reaction pool, a filter and a liquid collecting cabin, wherein an output port of the grating filter pre-settling device is connected with an input port of the chemical reaction settling pond; the output port of the chemical reaction settling pond is connected with the input port of the acid leaching reaction pool through the pressure filter; the output port of the acid leaching reaction pool is connected with the liquid collecting cabin through the filter; a pH monitoring adjusting device is arranged on the chemical reaction settling pond; and a heating device is arranged on the acid leaching reaction pool.

Description

technical field [0001] The invention relates to a treatment method for chrome tanning wastewater, in particular to a resource treatment system and a treatment process for chrome tanning wastewater under normal temperature and pressure. Background technique [0002] Leather processing is a process in which animal skins such as cattle and pigs are used as raw materials to produce finished leather through chemical treatment and mechanical processing. It generally includes three stages of preparation, tanning and finishing. Since chrome tanning is currently the main tanning method for domestic and foreign leather tanning, the main pollutants in this section are inorganic salts and heavy metal chromium, resulting in chromium-containing wastewater. Wastewater discharge accounts for more than 8% of the total tanning water, and the discharge of high-content chromium waste liquid not only causes great pollution to the environment, but also causes a great waste of resources. [0003...

AI Technical Summary

Problems solved by technology

The existing alkali precipitation method basically uses a single agent. Although the removal rate of Cr is over 99%, there is little room for further improvement of the removal rate. However, the chromium sludge formed by these agents to treat chromium-containing wastewater has great differences in properties. Large, the sedimentation performance of chromium sludge generated by MgO is the best, followed by CaO, Na ＋ worst

In terms of cost, MgO is more expensive, and CaO is the cheapest, but the amount of CaO sludge is relatively large

Poor settling properties and large amount of sludge will lead to increased subsequent treatment costs, so it is urgent to develop a treatment method with high efficiency, low cost, and low chromium sludge output, and realize the recovery and resource utilization of chromium

Images