为研究无烟煤自身的导电特性,提高其导电性能,使无烟煤成为填料和电极材料的一部分,采用酸溶法制备了灰分0.13%的超纯无烟煤,采用粉末电阻率仪探索了含水率、灰分、压强、粒度及矿物质成分对超纯无烟煤导电性的影响规律。结果表明,无烟煤电导率随含水率和压强的升高呈上升趋势。随灰分降低电导率逐渐升高。灰分低于1.0%时,电导率随灰分降低而急剧升高。压强4.00MPa、含水率6.21%、粒度0.2~0.1mm,灰分降至0.13%时,无烟煤导电性最佳,其电导率为1.44×10-7S/cm。研究范围内,粒度对无烟煤电导率影响较小。煤中常见矿物质的电导率顺序为:黄铁矿>高岭石>二氧化硅>碳酸钙>硫酸钙;黄铁矿电导率最高,达1.32×10-2S/cm。无烟煤电导率随黄铁矿含量增加呈升高趋势,而随其他矿物质含量增加呈降低趋势。采用响应曲面模型优化正交试验结果,获得了无烟煤电导率与含水率、灰分及粒度之间的二次回归方程。含水率和灰分对无烟煤电导率测试结果的影响显著,其中灰分对电导率的影响程度最大,含水率次之,粒度最小。

In order to study the electroconductivity of anthracite and improve its conductivity, and make anthracite become a part of fillerand electrode materials, ultra-pure anthracite with ash content of 0.13% was prepared by acid solution method. The effects of moisture,ash content, pressure, particle size and mineral composition on the electroconductivity of ultra - pure anthracite were investigated bypowder resistivity tester. The results show that the electrical conductivity of anthracite increases with the increase of moisture and pressure.The electrical conductivity increases gradually with the decrease of ash content. The electrical conductivity increases sharply with the ashcontent decreasing when the ash content is less than 1.0%. When the pressure is 4.00 MPa, the moisture is 6.21%, the particle size is 0.20.1 mm, and the ash content is reduced to 0.13%, the electrical conductivity of anthracite is the best, and its electrical conductivity is1.44×10-7 S/ cm. In the study range, the influence of particle size on the conductivity of anthracite is small. The order of electrical conductivity of common minerals in coal is: pyrite > kaolinite > silica > calcium carbonate > calcium sulfate, pyrite has the highest conductivityvalue, which reaches 1.32×10-2 S/ cm. The electrical conductivity of anthracite increases with the increase of pyrite content, but decreaseswith the increase of other mineral content. The response surface model is used to optimize the orthogonal experimental results, and thequadratic regression equation between the electrical conductivity of anthracite and moisture, ash content and particle size is obtained. Theinfluence of moisture and ash content on the conductivity testing results of anthracite is significant, in which ash has the greatest influenceon conductivity, followed by moisture and particle size.

0 引言

1 试验

   1.1 试验煤样

   1.2 研究方法及测试装置

2 结果与讨论

   2.1 超纯无烟煤的制备

   2.2 无烟煤导电性影响因素

3 结论