Influence of Vanadium Tailings from Stone Coal on Sintering Brick for Building

Abstract

Fired bricks for building were prepared from the tailings of vanadium extraction from stone coal. The influences of fineness and addition of tailing on the water absorption and compressive strength of samples were investigated. The mechanism of tailoring the phase compositions and microstructures of samples by tailing addition was analyzed by XRD and SEM. The freeze-thaw resistance and utilization safety of the products were tested. The results showed increasing the tailing fineness enhanced the microstructure densification and compressive strength, which firstly increased and then decreased after increasing tailing addition. B3 sample (tailings∶Clay∶fly ash = 30∶30∶40) fired at 1150 ℃ had the compressive strength of ≥35 MPa and the water absorption of ≤ 13%. The comprehensive properties meet the requirements of the Mu30 standard in the《sintered ordinary bricks》(GB/T 5101-2003). XRD and SEM analysis showed that adding 15%~30% tailing was beneficial to the formation of glass phase and promote the production of anorthite as well as anorthosite. Grain and liquid phase are cemented with each other, thus endowing the products with high compressive strength, microstructure densification, and good freeze-thaw resistance.

Keywords

• vanadium tailings from stone coal
• fired brick for building
• microstructure
• performance