Method for preparing anti-hardening granulous ceramic iron-carbon micro-electrolysis filler by using industrial waste

A method for preparing un-hardened ceramic micro-electrolysis fillers by industrial solid wastes, included the following steps:

• (1) mix a scrap iron, a lignin, a red mud and a clay at mass ratio of (4-5):(2-3):(1-3):3 as a mixture, and dry the mixture for 2-4 h at 105-110° C., and then crush the mixture through 100 mesh sieves;
• wherein the scrap iron contains Fe 90%-95%, the lignin contains cellulose 60%-70%, the red mud prepared from Bayer process which contains SiO2 18-20%, Al2O3 12-15%, Fe2O3 14-17%;
• (2) make the pretreated mixture of scrap iron, lignin, red mud and clay in step (1) into pellets which have a diameter of 5-6 mm, and then dry the pellets at room temperature for 20-24 h;
• (3) sinter the dried pellets from step (2) at 300-400° C. for 10-15 min, and sinter at 800-900° C. for 20-25 min at the absence of oxygen, and cool down the temperature below 100° C., and then store in sealed bags.