A method for resource utilization of cold-rolled pickling waste liquid

Abstract

This invention belongs to the field of metallurgical wastewater treatment technology and discloses a method for the resource utilization of cold rolling pickling waste liquid, including the following steps: 1) The pickling waste liquid is collected and enters a waste liquid collection tank, where it is homogenized and adjusted; 2) The homogenized and adjusted pickling waste liquid is first subjected to a security filter for preliminary impurity removal, and then subjected to an ultrafiltration membrane module for deep impurity removal to obtain ultrafiltration permeate; 3) The ultrafiltration permeate is concentrated by a membrane distillation system to obtain membrane distillation concentrate; 4) The membrane distillation concentrate is first subjected to a primary chelating resin for coarse removal of metal ions, and then subjected to a secondary chelating resin for fine removal of metal ions to obtain purified acid, which is used as acid for cold rolling pickling. This invention purifies the pickling waste liquid by removing impurities and concentrating it to meet the requirements for pickling acid, and then returns it to the rolling mill for reuse, reducing the discharge of pickling waste liquid and the consumption of acid in the pickling and rolling mill.

Images