Preparing powder raw materials of permeable bricks by ball milling using electric porcelain wastes

The influence of ball milling process on the ball milling efficiency of electric porcelain wastes was investigated, and the permeable bricks were prepared by using the ball milled electric porcelain waste powders as the raw materials. The results show that, the particle size of electric porcelain waste powders gradually decreases with the extension of ball milling time, and firstly decreases and then increases with the increase of ball milling speed, indicating that the ball milling efficiency first increases and then decreases. Due to the high hardness of electric porcelain waste, the particle size of the powders decreases with the increase of the large ball proportion in the milling ball. After the decrease of the middle ball proportion, the particle size of the powders increases with the increase of the large ball proportion. When the charge amount is less than 35%, the particle size of the electric porcelain waste powders gradually increases, and the ball milling efficiency gradually decreases. When the charge amount is more than 35%, the increasing rate of particle size is accelerated, and the ball milling efficiency is rapidly lowered. By optimizing the ball milling process of electric porcelain wastes and considering the comprehensive performance of the permeable bricks, the suitable ball milling time is 20 h, the ball milling speed is 140 r·min^‒1, the ratio of large, medium, and small stage of porcelain ball is 5:3:2, and the charge amount is 35%. The median diameter of the electric porcelain waste powders after ball milling is 4.1 μm, the sieve residue is 15%. The permeable bricks with the compressive strength of 6.1 MPa and the permeability coefficient of 0.028 cm·s^‒1 are prepared by using the ball milled electric porcelain waste powders as the main raw materials.