WANG Yongqing1, BAO Zhilei2, YANG Ke3, YANG Yulong4
(School of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403, Jiangxi, China)
Abstract: Water-permeable bricks were prepared by mainly using as an aggregate the recycled South Jiangxi rare earth tailings from which kaolin was separated, and appropriate amounts of low temperature sand, mid-temperature sand, black talc, limestone and clay as sintering aids. The effects of the content of the tailings and the preparation processes on the bending strength and permeation coefficient of waterpermeable bricks were studied. The results show that the bending strength decreased with the increase of the tailings content. However, the permeation coefficient firstly increased, then decreased, and it reached the maximum value when the tailings content was 75wt.%. Under the conditions of the tailings content of 75wt.%, the molding pressure of 12 MPa, the sintering temperature of 1240 °C and the holding time of 30min, the obtained water-permeable bricks have the bending strength of 5.5 MPa and the permeation coefficient of 3.0×10-2 cm/s.
Key words: ionic rare earth tailings; water permeable bricks; process conditions; bending strength; permeation coefficient