澳大利亚Bowen盆地与Surat盆地煤层特征及应用

Bowen盆地二叠系Bandanna组煤层固定碳含量为45%~60%,Surat盆地侏罗系Walloon亚群煤层固定碳含量为20%~40%,Bowen盆地煤层煤化程度高于Surat盆地煤层。显微组分实验显示Bowen盆地煤层镜质组含量为30%~90%,壳质组含量小于5%,Surat盆地煤层镜质组含量大于70%,壳质组含量10%~20%,Surat盆地煤层生烃潜力大于Bowen盆地。Bowen盆地煤层镜质体反射率值位于0.73%~0.96%之间,为Ⅱ型与Ⅲ型中煤级烟煤,适合做燃料,同时也可用作炼焦原料。Surat盆地煤层镜质体反射率值位于0.4%~0.65%之间,为低煤级煤和Ⅰ型中煤级褐煤,褐煤热解后可以制作半焦和煤焦油,可进行煤层气开发。通过分析Bowen盆地及Surat盆地煤层特点,认为澳大利亚煤质优良,投资环境良好,中国的石油、煤炭、电力、基础设施建设企业可以组建联合公司前往澳大利亚投资,并提前做好充分的尽职调查以及应对方案,以降低投资风险。

Application of extension neural network to safety status pattern recognition of coalmines

In order to accurately and quickly identify the safety status pattern of coalmines,a new safety status pattern recognition method based on the extension neural network (ENN) was proposed,and the design of structure of network,the rationale of recognition algorithm and the performance of proposed method were discussed in detail.The safety status pattern recognition problem of coalmines can be regard as a classification problem whose features are defined in a range,so using the ENN is most appropriate for this problem.The ENN-based recognition method can use a novel extension distance to measure the similarity between the object to be recognized and the class centers.To demonstrate the effectiveness of the proposed method,a real-world application on the geological safety status pattern recognition of coalmines was tested.Comparative experiments with existing method and other traditional ANN-based methods were conducted.The experimental results show that the proposed ENN-based recognition method can identify the safety status pattern of coalmines accurately with shorter learning time and simpler structure.The experimental results also confirm that the proposed method has a better performance in recognition accuracy,generalization ability and fault-tolerant ability,which are very useful in recognizing the safety status pattern in the process of coal production.

Approach to increasing the quality of pressure-relieved gas drained from protected coal seam using surface borehole and its industrial application

During mining of lower protective coal seam, a surface borehole can efficiently extract not only the pressure-relieved gas from the protected layer, but also the gas from the mining layer gob. If the distance between the borehole and gob is too large, the quantity of gas drained from the protected layer decreases substantially. To solve this problem, a mathematical model for extracting pressure-relieved gas from a protected coal seam using a surface borehole was established, based on the radial gas flow theory and law of conservation of energy. The key factors influencing the quantity of gas and the drainage flow network using a surface borehole were presented. The results show that the quantity of pressure-relieved gas drained from the protected layer can be significantly increased by increasing the flow resistance of the borehole bottom. Application of this method in the Wulan Coal Mine of the Shenhua Group significantly increased the flow of pure gas and the gas concentration （by factors of 1.8 and 2.0, respectively）, thus demonstrating the remarkable effects of this method.

Features and correct application of coal vitrinite reflectance index

The law of mathematical statistics, which the coal vitrinite reflectance index obeys, the existing vitrinite representing deviations, and the advantages of judging coalification and the shortage of judging coal type were analyzed. The advantages and disadvantages of various determination methods and the expression index and different methods of identifying vitrinite on the determination results were compared. The vitality of coal vitrinite reflectance depends on its full play the unique function of reflectance histogram and the systematic errors between different determination methods do not affect the application based on reflectance histogram are considered.

Application of fulllength anchor support technology in a largesection roadway under complicated geological conditions

Coal roadway support is the foundation and strong guarantee of safe coal production. With the FLAC3D numerical simulation, the roadway fulllength anchor support mechanism was studied, and the full-length anchor forcetransferring mechanism and stressfield distribution formed by roadway surrounding rocks were analyzed, which will provide a scientific basis for a support technology in large-section roadways under complicated geological conditions and lay a foundation for the popularization and application of a full-length anchor support system under special geological conditions.