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The effects of temperature, ore/coke ratio and atmosphere on the interaction between coke degradation and iron ore reduction was experimentally investigated under two blast-furnace atmospheres: full oxygen blast furnace (FOBF) under hydrogen-enriched operation and traditional blast furnace. The results indicated that the reaction temperature has a highly important impact on the solution loss reaction of coke during gasification, which is limited up to 1 100 degrees C but considerably increased as temperature rises to more than 1 200 degrees C, and that with increasing iron ore:coke ratio the solution loss reaction is accelerated while the sinter reduction index slightly decreases. Under the atmosphere of the H-enriched full oxygen blast furnace, the sinter reduction index was no less than 91.3% at 1 000 degrees C for 180 min. yet the coke solution loss ratio was no more than 3.7%. Under the normal blast-furnace atmosphere the sinter reduction index was 54.3%, suggesting that further reduction of sinter needs to occur sequentially in the high-temperature zone, and the solution loss ratio was c.2.0-2.7%. It is concluded that in the new H-enriched FOBF process the ore requirements for reduction index and softening start temperature T(A) can be lowered, the T(A) to 1 050-1 100 degrees C, whereas for the traditional process the reduction index should be improved and T(A) can be increased to more than 1 100-1 150 degrees C., The effects of temperature, ore/coke ratio and atmosphere on the interaction between coke degradation and iron ore reduction was experimentally investigated under two blast-furnace atmospheres: full oxygen blast furnace (FOBF) under hydrogen-enriched operation and traditional blast furnace. The results indicated that the reaction temperature has a highly important impact on the solution loss reaction of coke during gasification, which is limited up to 1 100 degrees C but considerably increased as temperature rises to more than 1 200 degrees C, and that with increasing iron ore:coke ratio the solution loss reaction is accelerated while the sinter reduction index slightly decreases. Under the atmosphere of the H-enriched full oxygen blast furnace, the sinter reduction index was no less than 91.3% at 1 000 degrees C for 180 min. yet the coke solution loss ratio was no more than 3.7%. Under the normal blast-furnace atmosphere the sinter reduction index was 54.3%, suggesting that further reduction of sinter needs to occur sequentially in the high-temperature zone, and the solution loss ratio was c.2.0-2.7%. It is concluded that in the new H-enriched FOBF process the ore requirements for reduction index and softening start temperature T(A) can be lowered, the T(A) to 1 050-1 100 degrees C, whereas for the traditional process the reduction index should be improved and T(A) can be increased to more than 1 100-1 150 degrees C.

COREX is a clean process, releasing less pollution and consuming smaller amounts of coke than the blast-furnace process, but the COREX shaft furnace is often subject to a serious sticking phenomenon that causes many problems for normal operation. In this study, the loading reduction experiments of iron ore pellets were carried out under the simulated COREX reducing conditions. The influence of temperature and H2 content in the syngas on the sticking behaviour of the pellets was observed by scanning electron microscope, energy-dispersive spectrometer and X-ray diffraction. The results indicated that the sticking index increased from 6.7 to 90.43%, when the temperature increased from 750 to 950 degrees C. The main composition of sticking material was metallic iron, and the sticking behaviour depended upon the amount and morphology of precipitated iron on the pellets' surface. It was concluded that the sticking mechanism was the interpenetrating diffusion mechanism of iron atoms between the adjacent pellets., COREX is a clean process, releasing less pollution and consuming smaller amounts of coke than the blast-furnace process, but the COREX shaft furnace is often subject to a serious sticking phenomenon that causes many problems for normal operation. In this study, the loading reduction experiments of iron ore pellets were carried out under the simulated COREX reducing conditions. The influence of temperature and H2 content in the syngas on the sticking behaviour of the pellets was observed by scanning electron microscope, energy-dispersive spectrometer and X-ray diffraction. The results indicated that the sticking index increased from 6.7 to 90.43%, when the temperature increased from 750 to 950 degrees C. The main composition of sticking material was metallic iron, and the sticking behaviour depended upon the amount and morphology of precipitated iron on the pellets' surface. It was concluded that the sticking mechanism was the interpenetrating diffusion mechanism of iron atoms between the adjacent pellets.