A paste-like self-flowing pipeline transportation backfilling technology with coal gangue as aggregate is proposed to remove the potential damage caused by coal gangue piles. As well, the difficult problems of recover...A paste-like self-flowing pipeline transportation backfilling technology with coal gangue as aggregate is proposed to remove the potential damage caused by coal gangue piles. As well, the difficult problems of recovering high quality safety coal pillars and deep mining of the Suncun Coal Mine （SCM）, Xinwen Coal Group, Shandong are resolved. The physical-chemical properties of coal gangue, optimized proportion of materials, backfilling system and craft in the SCM were studied in the laboratory and then an industrial test was carried out on high quality coal pillars under a town. The results show that finely crushed kaolinized and fresh gangue with granularity less than 5 mm can be used as aggregate with fly ash to replace part of the cement and a composite water reducer as an additive, accounting for 1.0%-1.5% of the total amount of cement and fly ash. The recommended proportion is l（cement）：4（fly ash）： 15（coal gangue）, with a mass fraction of 72%-75%, rheoiogical paste-like properties and a strength of more than 0.7 MPa at 7 d. The sequence of adding cement, fly ash, water reducer and then coal gangue ensures that the suspended state of the slurry, reducing the wear and jam of pipelines. The working face is advancing continuously by the alternating craft of building block walls with coal gangue and backfilling mined-out gobs with paste-like slurry. The recovery rate is as high as 90% with a backfilling cost of 36.9 YuarffL good utilization of coal gangue and no subsidence on the surface. This technology provides a good theoretical basis and application experience for coal mines, cement backfilling with paste-like slurry.展开更多
In this study, the properties of self-flowing ultra-low cement castables in Al2O3-SiC-C system have been investigated and compared to vibration castables. The major physical and mechanical properties, microstructure a...In this study, the properties of self-flowing ultra-low cement castables in Al2O3-SiC-C system have been investigated and compared to vibration castables. The major physical and mechanical properties, microstructure and corrosion behavior of these castables against slag have been evaluated. The results showed that the microstructure of Al2O3-SiC-C self-flowing castable is more uniform than the vibrated structure. Also self-flowing castable has smaller pore size and more uniform pore size distribution. Hence, density, strength, oxidation and slag resistance of the self-flowing castables is higher than that of vibration castables. Therefore, besides other benefits such as noise free, easy installation, fewer mold defects and reduced installation costs, Al2O3-SiC-C self flowing ultra low cement castables will have longer service life in comparison with vibration casables.展开更多
The existing problems of corundum self-flowing castables for ladles were expounded and the experimental study was carried out on the basis of the conventional proportion. The corundum self-flowing castables of excelle...The existing problems of corundum self-flowing castables for ladles were expounded and the experimental study was carried out on the basis of the conventional proportion. The corundum self-flowing castables of excellent properties were obtained by changing the kinds of water reducers and active alumina powders, and super bauxite instead of brown corundum on the basis of the optimal scheme for cost reduction. The industrial test of the corundum self-flowing castable,was carried out in a 120 t converter workshop of Liusteel. The service life of the castable synchronized with the well blocks and the purging plugs, which could meet the requirements of the ladle.展开更多
YB/T 4197-2009 1 Scope This standard specifies the term and definition,classification,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of ...YB/T 4197-2009 1 Scope This standard specifies the term and definition,classification,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of self-flow refractory castables.This standard is mainly applicable to high alumina,corundum,corundum spinel,and chrome corundum based self-flow refractory castables.2 Normative References展开更多
基金Projects 2006BAB02A03 supported by the National Key Technology Research and Development ProgramProjects 2006BA02B05 by the 11th Five Year Key Program for Science and Technology Development of China
文摘A paste-like self-flowing pipeline transportation backfilling technology with coal gangue as aggregate is proposed to remove the potential damage caused by coal gangue piles. As well, the difficult problems of recovering high quality safety coal pillars and deep mining of the Suncun Coal Mine （SCM）, Xinwen Coal Group, Shandong are resolved. The physical-chemical properties of coal gangue, optimized proportion of materials, backfilling system and craft in the SCM were studied in the laboratory and then an industrial test was carried out on high quality coal pillars under a town. The results show that finely crushed kaolinized and fresh gangue with granularity less than 5 mm can be used as aggregate with fly ash to replace part of the cement and a composite water reducer as an additive, accounting for 1.0%-1.5% of the total amount of cement and fly ash. The recommended proportion is l（cement）：4（fly ash）： 15（coal gangue）, with a mass fraction of 72%-75%, rheoiogical paste-like properties and a strength of more than 0.7 MPa at 7 d. The sequence of adding cement, fly ash, water reducer and then coal gangue ensures that the suspended state of the slurry, reducing the wear and jam of pipelines. The working face is advancing continuously by the alternating craft of building block walls with coal gangue and backfilling mined-out gobs with paste-like slurry. The recovery rate is as high as 90% with a backfilling cost of 36.9 YuarffL good utilization of coal gangue and no subsidence on the surface. This technology provides a good theoretical basis and application experience for coal mines, cement backfilling with paste-like slurry.
文摘In this study, the properties of self-flowing ultra-low cement castables in Al2O3-SiC-C system have been investigated and compared to vibration castables. The major physical and mechanical properties, microstructure and corrosion behavior of these castables against slag have been evaluated. The results showed that the microstructure of Al2O3-SiC-C self-flowing castable is more uniform than the vibrated structure. Also self-flowing castable has smaller pore size and more uniform pore size distribution. Hence, density, strength, oxidation and slag resistance of the self-flowing castables is higher than that of vibration castables. Therefore, besides other benefits such as noise free, easy installation, fewer mold defects and reduced installation costs, Al2O3-SiC-C self flowing ultra low cement castables will have longer service life in comparison with vibration casables.
文摘The existing problems of corundum self-flowing castables for ladles were expounded and the experimental study was carried out on the basis of the conventional proportion. The corundum self-flowing castables of excellent properties were obtained by changing the kinds of water reducers and active alumina powders, and super bauxite instead of brown corundum on the basis of the optimal scheme for cost reduction. The industrial test of the corundum self-flowing castable,was carried out in a 120 t converter workshop of Liusteel. The service life of the castable synchronized with the well blocks and the purging plugs, which could meet the requirements of the ladle.
文摘YB/T 4197-2009 1 Scope This standard specifies the term and definition,classification,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of self-flow refractory castables.This standard is mainly applicable to high alumina,corundum,corundum spinel,and chrome corundum based self-flow refractory castables.2 Normative References
