Effect of Mild-calcined Coal Gangue Additionon Hot Strength and Refractoriness Under Loadof Ultra Low Cement Castablesin Al_2O_3-SiO_2 System

This work explored the way to improve hot modulus q/＇ rupture （HMOR） and refractoriness under load （RUL） by adding mild-calcined coal gangue （MCG） in Al2O3 -SiO2 ultra low cement （ULC） castables, making use of the in-situ effect of the MCG during heating-up. The influence of respective additions of 5%, 10% and 1.5% of the MCG powders calcined at 700℃ was investigated on HMOR at 1400 ℃ and RUL of the castables. With increased addition of the MCG, HMOR and RUL become significantly enhanced. At 10% of the MCG addition, HMOR reaches 3 MPa, as compared to 0. 3 MPa in the case of no MCG addition. RUL of the specimens dried at 110 ℃for 24 h can be increased by some 270 ℃ with 10% of the MCG addition. RUL 0.11 the specimens preheated at 1 500℃ for 3 h maintains the growth trend with the MCG addition increasing. The microstructure of the heated castable samples was investigated by means of SEM. The in-situ formed needle-like and interlaced mullite in the matrix is contributive to the tmprovement.

电感耦合等离子体发射光谱-逐级化学提取法研究低硫煤矸石中微量元素的赋存状态及其环境效应

煤矸石是我国堆存量最大的工业固体废物，本文应用电感耦合等离子体发射光谱法、逐级化学提取法和相关性分析研究了淮北临涣矿区低硫煤矸石中10种微量元素的含量及赋存状态，并运用风险评价指数法评价其环境效应。结果表明，低硫煤矸石中Ba、Co、Cr、Mn、Ni、Pb、V含量均高于淮北煤和中国煤均值，Mn、V的富集系数大于1，有一定迁移风险。微量元素主要以残渣态和铁锰氧化物结合态存在，两者质量分数之和为68．87％～92．93％，其中Cd、Co、Cr、Cu、Ni、Pb、zn赋存于硫化物矿物中，V赋存于黏土矿物中，Mn赋存于碳酸盐矿物和硫化物矿物中．10种微量元素对环境的危害性大小为：Mn〉Zn〉Ni〉Pb〉Cd〉Cu〉Ba〉V〉Cr〉Cc），表明低硫煤矸石堆存过程中活性态Mn对生态环境造成危害的可能性最大，由Mn可能引起的煤矸石山周边地区土壤及水体污染应当重视．

利用巨大芽孢杆菌处理高硫和低硫煤矸石制备肥料的研究

煤矸石的大量堆积严重威胁到环境和人类身体健康,采用绿色环保的方法处理煤矸石,是对其进行综合利用的有效途径。利用巨大芽孢杆菌（ACCC10011）处理分解煤矸石制备煤矸石肥料,探索了煤矸石粒度、接菌量、体系p H、培养时间、温度、震荡条件及干湿条件对其分解效果的影响,得到煤矸石肥料制备的最佳条件。结果表明：在巨大芽孢杆菌分别处理贵州六盘水低硫煤矸石和黔南地区高硫煤矸石制得的两种肥料中,低硫、高硫煤矸石肥料制备的最优条件分别为：粒径均为20目,体系pH均为8,接菌量分别为40m L（即5.44×10^10～1.48×10^11cfu/m L）和50m L（即6.8×10^10～1.85×10^11cfu/m L）,培养时间分别为5d和1d,培养温度均为30℃;与原煤矸石相比,低硫、高硫煤矸石肥料中有效磷、速效钾和碱解氮提高倍数分别为33.96倍和29.67倍、6.83倍和12.14倍、1.27倍和1.56倍。