Ceramic Bricks Preparation from Tungsten Tailings

Tungsten tailings are solid waste discharged from tungsten-bearing minerals in tungsten ores. China's tungsten resources have very low taste and few rich ores, and only 20% of the tungsten grade (WO₃) is greater than 0.5%. As a result, a large number of tungsten tailings are produced in the process of beneficiation.

At present, the main raw materials for preparing ceramics include kaolin, ceramics stone, silica raw materials, feldspar raw materials and talc, while traditional ceramics in China mainly use kaolin-feldspar-quartz ternary raw material formula, the quality of raw materials varies in different places. In the preparation of ceramics, the sintering temperature of ceramics is generally above 1100 ℃. Tungsten tailings are used as the main raw material, and the quality percentage is as high as 80%-90%. This can reduce the cost of raw materials and make up for the shortage of traditional raw materials in the ceramic industry.

1.Raw material pretreatment: Tungsten tailings are scorched at 600-900 ℃ for 1-2 hours to remove moisture and volatile impurities and improve sintering activity of tungsten tailings.

2.Batch preparation: The pretreated tungsten tailings and albite are weighed, mixed and milled in a certain proportion, through 200-300 mesh sieves, and a small amount of binder is added to make the mixture evenly.

3.Formation of ceramic bricks: The ceramic bricks is made by placing the mixture evenly into the metal mould and forming under one-sided pressure with the forming pressure of 20-30 MPa.

4.Drying of ceramic bricks: Put the pressed ceramic bricks into air for 1-3 hours or put it in a drying box at 110 ℃ for 0.5-1 hours to evaporate the water in the ceramic bricks and give the green body a certain strength. The strength value only ensures the strength required for the body to be transported to the sintering furnace.

5.Firing of ceramics: The dried ceramic bricks is placed in a sintering furnace and heated at a rate of 3-5 C/min. The high strength ceramics can be made by holding at 500 ℃ for 1 hour, then at 1000-1075 ℃ for 1-3 hours. After cooling in the furnace, the high strength ceramics can be obtained. The ceramics are mainly composed of quartz, cristobalite, calciferous feldspar and a small amount of hematite crystalline phase, and contain a small amount of glass phase.

The main raw material of high strength ceramics is tungsten tailings, whose quality percentage is as high as 80%-90%. The main components of tungsten tailings are SiO₂ and AlO₃, and the quality percentage is more than 80%. SiO₂ and AlO₃ play a skeleton role in ceramic materials, which can give ceramics excellent mechanical properties, thermal properties and chemical stability. The preparation conditions are simple, easy to operate, fewer kinds of raw materials, and high yield, which is conducive to large-scale production.

• < Prev
• Next >