Wetting Heat of various ranks of coals in water was measured by using SETARAM C80D Calorimeter. The data were correlated to coals' slurryability which is characterized by the solid load at the viscosity of 1 Pa...Wetting Heat of various ranks of coals in water was measured by using SETARAM C80D Calorimeter. The data were correlated to coals' slurryability which is characterized by the solid load at the viscosity of 1 Pa's and 25℃. The results showed that the heat of wetting by wa-ter decreases as coal rank increases in the range of brawn coal to bituminous coaI with carbon content of 89% ~90% (daf), and then, increases a little for anthracite. This trend fitted well to the relationship of slurryability to coal rank. The heat of wetting was also correlated to the inher-ent moisture content and the oxygen content of coal, which are commonly considered as slurrya-bility indication parameters. Hence, the wetting heat is another measure of coal's slurryability.展开更多
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 h...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.展开更多
文摘Wetting Heat of various ranks of coals in water was measured by using SETARAM C80D Calorimeter. The data were correlated to coals' slurryability which is characterized by the solid load at the viscosity of 1 Pa's and 25℃. The results showed that the heat of wetting by wa-ter decreases as coal rank increases in the range of brawn coal to bituminous coaI with carbon content of 89% ~90% (daf), and then, increases a little for anthracite. This trend fitted well to the relationship of slurryability to coal rank. The heat of wetting was also correlated to the inher-ent moisture content and the oxygen content of coal, which are commonly considered as slurrya-bility indication parameters. Hence, the wetting heat is another measure of coal's slurryability.
基金partly supported by the National Natural Science Foundation of China (No.51404263)the National Natural Science Foundation of Jiangsu Province (No.BK20130203)+3 种基金the Coal Mine Joint Funds of the National Natural Science Foundation of China (No.51134023)the State Key Laboratory Cultivation Base for Gas Geology and Gas Control (No.WS2013A05)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the independent study for State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology (No.SKLCRSM09X04)
文摘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.
