To reduce the burning loss and the spalling and to improve energy efficiency,the mullite composite lining plates were used to replace cast steel or alloy lining in rotary coke tanks for coke dry quenching equipment.Th...To reduce the burning loss and the spalling and to improve energy efficiency,the mullite composite lining plates were used to replace cast steel or alloy lining in rotary coke tanks for coke dry quenching equipment.The results show that:the dense mullite composite lining plate in the cone part has the density of 2.20 g·cm^(-3) and the wear test,s volume loss of 4.08 cm^(3),and the light weight mullite composite lining plate in the straight cylinder part has the density of 1.95 g·cm^(-3) and the wear test,s volume loss of 17.6 cm^(3).After using,there is no shrinkage gap,no burn loss or holes in the plates,indicating good sealing of the mullite composite lining plates.The lining plate for the cone part has low burning loss,without spalling for more than half a year.The outer surface temperature of coke tanks adopting the cast steel or the alloy lining is 480 to 570℃,while that of the ones adopting mullite composite lining plates is 120 to 170℃,showing a largely improved insulating property.Adopting mullite composite lining plates on the basis of the current coke tank cage,the lining plates can be timely treated and wholly replaced,improving the service life and reducing the maintenance workload.展开更多
The mullite-SiC castables for coke dry quenching（CDQ）furnace corbel pillar were prepared by taking mullite and silicon carbide as aggregates,silicon carbide powder,fused silica powder,α-Al2O3powder and silica fume ...The mullite-SiC castables for coke dry quenching（CDQ）furnace corbel pillar were prepared by taking mullite and silicon carbide as aggregates,silicon carbide powder,fused silica powder,α-Al2O3powder and silica fume as matrix,calcium aluminate cement as binding system,and extra-adding steel fibers to extend the CDQ furnace refractory life.The effects of steel fiber types（melt pumping meniscus,cut straight,wavy indentation,cold-drawn hook）and steel fiber extra-additions（0,1%,2%,3%by volume）on the properties of mullite-SiC castables were investigated.Then the toughening mechanism of steel fiber in the castables was analyzed according to the load-displacement curves.The results show that：（1）the toughening effects of the melt pumping meniscus steel fiber with rough surface and colddrawn hook steel fiber with strong anchoring effect with the matrix are better than those of cut straight steel fiber and wavy indentation steel fiber;（2）the suitable amount of steel fiber（less than 2%）in mullite-SiC castables not only significantly improves the mechanical properties,thermal shock resistance and wearing resistance,but also improves the fracture energy by 49.0%and slows the crack growth;（3）the bond strength and mechanical anchoring force between steel fiber and castable interface are key elements of steel fiber reinforced castables.展开更多
In order to prolong the service life of the cooling zone of large scale coke dry quenching ovens,six kinds possible refractories for the cooling zone of large scale coke dry quenching ovens： SiC containing brick A,Si...In order to prolong the service life of the cooling zone of large scale coke dry quenching ovens,six kinds possible refractories for the cooling zone of large scale coke dry quenching ovens： SiC containing brick A,SiC containing brick B,mullite-andalusite brick,spinel containing brick,zirconia containing brick,corundum-mullite brick and grade B mullite brick,were analyzed in properties. It is found that the cooling zone lining adopting SiC containing bricks or mullite-andalusite bricks has much longer service life. Based on this,a new type of wear resistant brick was developed. The brick has a compressive strength of 135 MPa,a wear loss of 2. 10cm^3（only a quarter of that of the grade B mullite brick）,and a higher bulk density than the grade B mullite brick. The application of the brick in a 140t·h^（-1）coke dry quenching oven showed that it performed better than the grade B mullite brick. The cooling zone adopting the new bricks has a lower coke discharging temperature,which is beneficial to the enhancement of heat recovery efficiency and steam power generation.展开更多
The mechanism of coke size segregation in the radial direction of pre-chamber in coke dry quenching （CDQ） shaft was investigated by experiment and numerical analysis. The experimental apparatus was a cold three-dime...The mechanism of coke size segregation in the radial direction of pre-chamber in coke dry quenching （CDQ） shaft was investigated by experiment and numerical analysis. The experimental apparatus was a cold three-dimensional semicircle model for bell-type charging, which was used to study the influences of different kinds of bells and different stock line levels on the radial distribution of coke size in the radial direction of a pre-chamber. A mathematical model was used, which is capable of estimating the radial average size distribution as well as the radial deposit distribution of each particle size for multiple size coke with a few fixed parameters. The calculated results agree well with the experimental data, which proves the reliability of both experimental study and numerical analysis.展开更多
文摘To reduce the burning loss and the spalling and to improve energy efficiency,the mullite composite lining plates were used to replace cast steel or alloy lining in rotary coke tanks for coke dry quenching equipment.The results show that:the dense mullite composite lining plate in the cone part has the density of 2.20 g·cm^(-3) and the wear test,s volume loss of 4.08 cm^(3),and the light weight mullite composite lining plate in the straight cylinder part has the density of 1.95 g·cm^(-3) and the wear test,s volume loss of 17.6 cm^(3).After using,there is no shrinkage gap,no burn loss or holes in the plates,indicating good sealing of the mullite composite lining plates.The lining plate for the cone part has low burning loss,without spalling for more than half a year.The outer surface temperature of coke tanks adopting the cast steel or the alloy lining is 480 to 570℃,while that of the ones adopting mullite composite lining plates is 120 to 170℃,showing a largely improved insulating property.Adopting mullite composite lining plates on the basis of the current coke tank cage,the lining plates can be timely treated and wholly replaced,improving the service life and reducing the maintenance workload.
文摘The mullite-SiC castables for coke dry quenching（CDQ）furnace corbel pillar were prepared by taking mullite and silicon carbide as aggregates,silicon carbide powder,fused silica powder,α-Al2O3powder and silica fume as matrix,calcium aluminate cement as binding system,and extra-adding steel fibers to extend the CDQ furnace refractory life.The effects of steel fiber types（melt pumping meniscus,cut straight,wavy indentation,cold-drawn hook）and steel fiber extra-additions（0,1%,2%,3%by volume）on the properties of mullite-SiC castables were investigated.Then the toughening mechanism of steel fiber in the castables was analyzed according to the load-displacement curves.The results show that：（1）the toughening effects of the melt pumping meniscus steel fiber with rough surface and colddrawn hook steel fiber with strong anchoring effect with the matrix are better than those of cut straight steel fiber and wavy indentation steel fiber;（2）the suitable amount of steel fiber（less than 2%）in mullite-SiC castables not only significantly improves the mechanical properties,thermal shock resistance and wearing resistance,but also improves the fracture energy by 49.0%and slows the crack growth;（3）the bond strength and mechanical anchoring force between steel fiber and castable interface are key elements of steel fiber reinforced castables.
文摘In order to prolong the service life of the cooling zone of large scale coke dry quenching ovens,six kinds possible refractories for the cooling zone of large scale coke dry quenching ovens： SiC containing brick A,SiC containing brick B,mullite-andalusite brick,spinel containing brick,zirconia containing brick,corundum-mullite brick and grade B mullite brick,were analyzed in properties. It is found that the cooling zone lining adopting SiC containing bricks or mullite-andalusite bricks has much longer service life. Based on this,a new type of wear resistant brick was developed. The brick has a compressive strength of 135 MPa,a wear loss of 2. 10cm^3（only a quarter of that of the grade B mullite brick）,and a higher bulk density than the grade B mullite brick. The application of the brick in a 140t·h^（-1）coke dry quenching oven showed that it performed better than the grade B mullite brick. The cooling zone adopting the new bricks has a lower coke discharging temperature,which is beneficial to the enhancement of heat recovery efficiency and steam power generation.
文摘The mechanism of coke size segregation in the radial direction of pre-chamber in coke dry quenching （CDQ） shaft was investigated by experiment and numerical analysis. The experimental apparatus was a cold three-dimensional semicircle model for bell-type charging, which was used to study the influences of different kinds of bells and different stock line levels on the radial distribution of coke size in the radial direction of a pre-chamber. A mathematical model was used, which is capable of estimating the radial average size distribution as well as the radial deposit distribution of each particle size for multiple size coke with a few fixed parameters. The calculated results agree well with the experimental data, which proves the reliability of both experimental study and numerical analysis.
