The penetration behavior of different kinds of coal ash slags into chrome corundum bricks was studied by cup test. As a preliminary attempt,the oxides of Fe2O3 and MgO were added into coal ash to reduce the erosion of...The penetration behavior of different kinds of coal ash slags into chrome corundum bricks was studied by cup test. As a preliminary attempt,the oxides of Fe2O3 and MgO were added into coal ash to reduce the erosion of refractories. Different cup tests were carried out to study coal slag erosion to the refractories. FactSage was used to simulate the phase diagram of the main chemical compositions in coal ash and in the refractories. Both results agreed with each other. The results show that the elements in coal slag can penetrate into bricks and the penetration deepens with the duration increasing; it is difficult for Fe but easier for Ca and Si to penetrate into bricks; different kinds of melting coal ashes penetrate into refractories differently and the penetration depth of silicon and calcium can be significantly reduced by adding oxides into coal ash.展开更多
The pressure drop of a cross-flow moving-bed was investigated in a two-dimensional rectangular apparatus.The effects of the particle velocity,the superficial gas veloc-ity,the formation and development of cavity/racew...The pressure drop of a cross-flow moving-bed was investigated in a two-dimensional rectangular apparatus.The effects of the particle velocity,the superficial gas veloc-ity,the formation and development of cavity/raceway and voidage of particles on the pressure drop were investigated experimentally under the operational conditions of 0.09–1.35 m/s of the superficial gas velocity and 0.95–9.68 cm/min of the particle velocity.The experimental results show that the particle velocity has little influence on the pressure drop,while the phenomena of cavity and pinning occur when the cross-flow velocity is high enough.The development of a cavity or a raceway can result in three types of variations of pressure drop with time:stabilization,slight fluctuation and severe fluctuation.A cavity appears in a process cycle of‘formation-growing up-collapsing-fluidization’at a high gas velocity.On the basis of experimental results,a model for calculating the pressure drop after a cavity occurs and a dimensionless relationship of cavity size is developed,which gives a good qualitative account of the experimental data.展开更多
文摘The penetration behavior of different kinds of coal ash slags into chrome corundum bricks was studied by cup test. As a preliminary attempt,the oxides of Fe2O3 and MgO were added into coal ash to reduce the erosion of refractories. Different cup tests were carried out to study coal slag erosion to the refractories. FactSage was used to simulate the phase diagram of the main chemical compositions in coal ash and in the refractories. Both results agreed with each other. The results show that the elements in coal slag can penetrate into bricks and the penetration deepens with the duration increasing; it is difficult for Fe but easier for Ca and Si to penetrate into bricks; different kinds of melting coal ashes penetrate into refractories differently and the penetration depth of silicon and calcium can be significantly reduced by adding oxides into coal ash.
文摘The pressure drop of a cross-flow moving-bed was investigated in a two-dimensional rectangular apparatus.The effects of the particle velocity,the superficial gas veloc-ity,the formation and development of cavity/raceway and voidage of particles on the pressure drop were investigated experimentally under the operational conditions of 0.09–1.35 m/s of the superficial gas velocity and 0.95–9.68 cm/min of the particle velocity.The experimental results show that the particle velocity has little influence on the pressure drop,while the phenomena of cavity and pinning occur when the cross-flow velocity is high enough.The development of a cavity or a raceway can result in three types of variations of pressure drop with time:stabilization,slight fluctuation and severe fluctuation.A cavity appears in a process cycle of‘formation-growing up-collapsing-fluidization’at a high gas velocity.On the basis of experimental results,a model for calculating the pressure drop after a cavity occurs and a dimensionless relationship of cavity size is developed,which gives a good qualitative account of the experimental data.
