Application study on complex wetting agent for dust-proof after gas drainage by outburst seams in coal mines

• Published in: International journal of mining science and technology 2016-07, Vol.26 (4), p.669-675
• Main Authors: Wang, Kai, Ma, Xiaoping, Jiang, Shuguang, Wu, Zhengyan, Shao, Hao, Pei, Xiaodong
• Format: Article
• Language: English
• Subjects: Complex wetting agent; Dust-proof; Spray; Tunneling face; Water injection; 呼吸性粉尘; 应用; 润湿剂; 煤矿; 瓦斯抽放; 突出煤层; 表面张力; 防尘效果
• ISSN: 2095-2686
• DOI: 10.1016/j.ijmst.2016.05.020

After gas drainage, the outburst seam is dry and, consequently, during subsequent mechanized mining, unwanted dust production is extensive. Because the hard dustfall typically has a small particle size it contains a high percentage of respirable dust. Considering these factors, this paper improved the efficiency of dustfall by reducing the surface tension of the liquid used as a wetting agent, then configuring five kinds of wetting agents by adopting various doses and types of surfactants, neutral inorganic salts and chemical additives, etc. After purchasing DA-85 and SRJ-1 wetting agent, the surface tension and critical micelle concentration of seven kinds of wetting agents were measured using the capillary rise method. Wetting agent A was confirmed to have the best comprehensive effect. The experiments were optimized by measuring and comparatively analyzing contact angles of pure water, SRJ-1 wetting agent and wetting agent A on the surface of different coal samples using a contact angle measurement instrument （HARKE- SPCA）. By comparative analysis, dust-proof effects of seam, dynamic pressure water infusion and high- pressure spray in the tunneling face at the Daning coal mine using pure water, wetting agent SRJ-1 and A, it was determined that after using wetting agent A, the average dust concentration in the place of the mining machine driver, 10 m and 110 m away from the tunneling front is approximately 300 rag/ m^3, 240 mg/m^3 and 100 mg/m^3, respectively, This practice increased the dust-proof efficiency dramati- cally and achieved a good comprehensive dust-proof effect.