Coking coal dust is extremely hydrophobic;therefore,combination with droplets in the air is difficult and dust suppression is challenging.Here,a dust suppressant spray for coking coal dust was studied in order to impr...Coking coal dust is extremely hydrophobic;therefore,combination with droplets in the air is difficult and dust suppression is challenging.Here,a dust suppressant spray for coking coal dust was studied in order to improve of the combination of droplets and coking coal dust.Based on monomer optimization and compounding analysis,two surfactant monomers,fatty alcohol ether sodium sulfate(AES)and sodium dodecyl benzene sulfonate(SDBS)were selected as the surfactant components of the dust suppressant.The surfactant monomers were combined with four inorganic salts and the reverse osmosis moisture absorption of each solution was determined.By combining the reverse osmosis moisture absorption values with the water retention experimental results,CaCl_(2)was identified as the optimal inorganic salt additive for the dust suppressant.Finally,the optimal concentration of each component was obtained using orthogonal experimental design i.e.,AES(0.03%),SDBS(0.05%),and CaCl_(2)(0.4%).The dust suppressant solution formulated using this method had a high moisture absorption capacity and excellent performance.展开更多
To study the flashover characteristics of the fog water in saline-alkali areas for high-speed railway OSC insulators,the spatial distributions of both the potential and electric field of soiled insulators in the prese...To study the flashover characteristics of the fog water in saline-alkali areas for high-speed railway OSC insulators,the spatial distributions of both the potential and electric field of soiled insulators in the presence of salty fog are analyzed using COMSOL Multiphysics,a multi-physics coupling software.Furthermore,to analyze the effect of the contamination of insulators due to salty fog water,a saline solution is used for staining an insulator sample by using the solid coating method.In an artificial climate chamber,the salty fog environment is simulated,and the flashover voltage for different salty fog water conductivities and surface staining are obtained.The salt-density correction coefficient K is also proposed.It provides a strong basis for the selection of railway insulators in saline-alkali areas.The results show that the salty fog water changes the original surface equivalent salt density,ρESDD,by wetting the existing fouling layer on the surface of the insulator,so that the original surface contamination layer becomes equivalent to KρESDD;the smaller is the value ofρESDD of the insulator surface,the larger is the value of K;the surface of the same insulator is dirty,and as the concentration of salty fog-water increases,K also increases.展开更多
基金The project was supported by the National Natural Science Foundation of China(No.51574123)the Scientific Research Project of Hunan Province Office of Education(No.18A185),which is gratefully acknowledged.
文摘Coking coal dust is extremely hydrophobic;therefore,combination with droplets in the air is difficult and dust suppression is challenging.Here,a dust suppressant spray for coking coal dust was studied in order to improve of the combination of droplets and coking coal dust.Based on monomer optimization and compounding analysis,two surfactant monomers,fatty alcohol ether sodium sulfate(AES)and sodium dodecyl benzene sulfonate(SDBS)were selected as the surfactant components of the dust suppressant.The surfactant monomers were combined with four inorganic salts and the reverse osmosis moisture absorption of each solution was determined.By combining the reverse osmosis moisture absorption values with the water retention experimental results,CaCl_(2)was identified as the optimal inorganic salt additive for the dust suppressant.Finally,the optimal concentration of each component was obtained using orthogonal experimental design i.e.,AES(0.03%),SDBS(0.05%),and CaCl_(2)(0.4%).The dust suppressant solution formulated using this method had a high moisture absorption capacity and excellent performance.
基金Supported by the Natural Science Foundation of China(51567014,51767014)the Scientific and Technological Research and Development Program of the China Railway(2017J010-C/2017)。
文摘To study the flashover characteristics of the fog water in saline-alkali areas for high-speed railway OSC insulators,the spatial distributions of both the potential and electric field of soiled insulators in the presence of salty fog are analyzed using COMSOL Multiphysics,a multi-physics coupling software.Furthermore,to analyze the effect of the contamination of insulators due to salty fog water,a saline solution is used for staining an insulator sample by using the solid coating method.In an artificial climate chamber,the salty fog environment is simulated,and the flashover voltage for different salty fog water conductivities and surface staining are obtained.The salt-density correction coefficient K is also proposed.It provides a strong basis for the selection of railway insulators in saline-alkali areas.The results show that the salty fog water changes the original surface equivalent salt density,ρESDD,by wetting the existing fouling layer on the surface of the insulator,so that the original surface contamination layer becomes equivalent to KρESDD;the smaller is the value ofρESDD of the insulator surface,the larger is the value of K;the surface of the same insulator is dirty,and as the concentration of salty fog-water increases,K also increases.