Papers by Author: Sheng Li Wu

Abstract: The changes of physical and chemical properties of sodium pyroxenite gangue such as decomposition and phase transformation were researched by means of differential thermal analysis and X-ray diffraction. The results show that the natural sodium pyroxenite gangue contains the main mineral of aegirite(NaFe⁺³Si₂O₆), and it contains a number of BaSO₄ and Na₃Ca₂(SO₄)₃F, etc. The water of crystallization decomposes at 554.7°C. The Na₃Ca₂(SO₄)₃F decomposes into the composite sulfate and CaF₂ over a wide range of temperatures. The main mineral of aegirite(NaFe⁺³Si₂O₆) reacts with CaF₂ into NaF gas at 993.4°C. The sodium pyroxenite gangue is melts and releases a small amount of SiF₄ gas in the range of 1193.5-1300.7°C.

Abstract: In this paper, the modes of occurrence of the trace elements of Na, K, Fe and Si in SX-Coal and SD-Coal, which were used for COREX process, were analyzed. The coal was treated by wet digestion method and then the content of trace elements was analyzed. After that, the modes of occurrence of the elements were studied by sequential extraction procedure method and analyzed by ICP-OES. The results showed that the content of Na element is the highest and the content of K and Si elements is very low among the four elements in both kinds of coal. Na and K elements mainly exist in the mode of residue in SX-Coal and SD-Coal, and they are tends to enriched in the residue during the pyrolysis. Fe and Si elements mainly exist in the mode of carbonate, iron oxides and manganese oxides in SD-Coal. Fe and Si are tends to be decomposed from the compounds during the pyrolysis.

Abstract: The sinter production is affected by many factors, including total iron content, gangue content and burning loss. These paper analyses changes of three kinds of Australian iron ores in recent ten years, and then draw a conclusion that the assimilability of these three kinds of Australian iron ores are increased. These kinds of changes cause a lot of influence upon sinter production, which means negative influence. Therefore, ore blending constitution is changed by iron ore quality degradation.

Abstract: Through analyzing and inspecting the raw materials conditions and process conditions that affect ferrous material reduction in the thermal reserve zone, the article indicates that for the three commonly used ferrous material of blast furnace, sinter, pellets and lump ore, sinter is easiest to reduce and lump ore is most difficult to reduce. And increasing of the size of ferrous material promote the reduction of the ferrous material slightly. With the increase of batch weight, weight loss of ore and coke decrease at first and then increase. With the increase of the ratio of coke/ore, the extent of reduction of ferrous material had not significantly improved.

Abstract: The bonding intensity of four kinds of ores from Brazil, Australia and South Africa is researched in this study, and the influence factors are analyzed. The results show that, the ores of different types have apparently differences in bonding intensity, ores from Brazil and South Africa have high bonding intensity, while ores from Australia have low bonding intensity; The foundation of generation of effective liquid is adequate liquid phase fluidity and the lower porosity of core ore; The ratio of porosity of core ore and the index of liquid phase fluidity has negative correlation with the bonding intensity.

Abstract: High-temperature properties of 10 samples of iron ore from Brazil, Australia and China were measured. Several conclusions were made based on these experimental results. Assimilability of Brazilian ore, Australian ore and Chinese ore concentrate were low, high and medium, respectively. Optimal fluidity of liquid phase was observed in 2 types of Brazilian ores (BR-B, BR-C), 1 type of Australian ore (AU-C) and 1 type of Chinese ore (CH-D). For self-strength of the bonding phase, Australian ore presented low levels, while Brazilian and Chinese ore presented high levels. According to the experimental results of high-temperature properties of iron ore, schemes of ore blending optimization were designed and sinter pot test using these blends were performed. The results indicated that ore blends composed of 30~45% Brazilian ores + 25~50% Australian ores + 20~30% Chinese concentrates presented excellent sintering results, considering both the performance of the processing and quality of the sinter. Therefore this experiment has proved that ore blending optimization combining high temperature properties can lead to more efficient sintering mixes.

Abstract: The shape feature of tuyere raceway possesses an important effect on hearth state and BF operation. With analyzing channel for permeating gas and liquid in the hearth section in the position of tuyere raceway, it can be seen that the channel amount is mainly determined by section of raceway and section between the raceways. On the basic of theoretical and statistical analysis on practical production data, the new evaluation index of indicating tuyere raceway shape feature was proposed. In the condition of high blast volume, the new index AITR tended to increase and BF production was improved gradually as blast volume increases. The good evaluation character of this new index AITR has been validated with practical production data in this work.

Abstract: The circumferential distribution characteristics of airflow in bustle pipe and each tuyere have been simulated and researched through establishing mathematical model of blast furnace (BF) hot blast systems. The disputes on the circumferential distribution characteristics of airflow in bustle pipe at home and abroad were settled. The results show that, under the premise of uniform pressure distribution in hearth and tuyere section area, except that of the nearest ones, the velocity of airflow in these tuyeres which are near to the main pipe is lower than those far away from the main pipe because of the existence of vortex. However, both the fluctuation range of all tuyeres’ air velocity and its influence on tuyere raceway depth are small and can be ignored.