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Lu Z.-H.,University of Science and Technology Beijing | Lu Z.-H.,Xinxing Cast Pipe Xinjiang Co. | Jin X.-H.,University of Science and Technology Beijing | Gao J.-T.,University of Science and Technology Beijing | And 3 more authors.
Guocheng Gongcheng Xuebao/The Chinese Journal of Process Engineering | Year: 2011

The direct reduction of iron was carried out by pellet preheating and one-step coal-based direct reduction process with the high grade magnetite concentrate from Mengku, Xinjiang, as raw material. The quality of preheated pellets at different preheating system conditions was examined in order to determine the effect of preheating process when magnetite concentrate pellets were reduced. Both the compressive strength and degradation index of preheated pellet are the important indicators to measure the preheating process. The green pellets could be preheated in a chain grate to improve the strength of the preheated pellets and reduce the degradation index of green pellet. Based on the preliminary analysis of results, the best preheating system was determined, that is, the preheating temperature was between 800 to 850°C, preheating time 15-18 min, preheating wind velocity from 1.5 to 1.8 m/s and the material layer thickness 100 mm, the preheated pellets produced would have the compressive strength as high as 600 N, which means that its compressive strength is obviously improved compared with the pellets produced at other preheated system. The experimental results of scale-up process show that the quality of directly reduced iron under these conditions could completely meet the following production requirement.


Lu Z.-H.,University of Science and Technology Beijing | Lu Z.-H.,Xinxing Cast Pipe Xinjiang Co Ltd. | Chen Y.,Xinxing Cast Pipe Xinjiang Co Ltd. | Chen D.-M.,University of Science and Technology Beijing | Li S.-Q.,University of Science and Technology Beijing
Journal of Iron and Steel Research | Year: 2011

Using Xinjiang magnetite concentrate, the process for preheated pellets with high strength and easy reduction, and coal-based direct reduction iron (DRI) were studied by novel one-step process for direct reduction. DRI production process of simulating tests of rotary in laboratory was studied. Influence of carbon capacity adding, reduction time, reduction temperature on the degree of metallization, sulphur content of rotary kiln DRI was analyzed. The best direct reduction process parameter of rotary kiln DRI production in this raw material conditions was proposed. The results show that for Xinjiang magnetite assaying with 64. 39%Fe, preheated pellets are directly reduced at 1025 °C for 70min, directly reduced iron (DRI) assaying 93% metallic iron and 95. 48% metallization degree are achieved. Compared with the traditional direct reduction of fired oxide pellets in coal-based rotary kilns, one-step process for direct reduction can avoid high temperature oxidation of pellets at 1150 - 1 300 °C, and possesses some advantages such as, greater economic profit, good quality of direct reduced iron.


Lu Z.-H.,University of Science and Technology Beijing | Lu Z.-H.,Xinxing Cast Pipe Xinjiang Co. | Gao J.-T.,University of Science and Technology Beijing | Li S.-Q.,University of Science and Technology Beijing | And 3 more authors.
Beijing Keji Daxue Xuebao/Journal of University of Science and Technology Beijing | Year: 2011

Experiments were done to study the physical dissociation of phosphorus and iron elements in typical high-phosphorus hematite ore samples from the Enshi area of Hubei Province, China. The basic characteristics analyses of the ore samples show the ore is a typical oolitic hematite in which iron and phosphorus elements are not in a chemical combination state, indicating that by the high-speed jet mill technology, the high-phosphorus hematite is finely ground to an average particle size of 2 μm. It is found that the contents of iron and phosphorus are not evenly distributed in the ultra-fine powders, meaning that the effective dissociation of iron and phosphorus elements is achieved in the ore. Then a fluidization device for pneumatic separation was designed and manufactured to investigate the fluidization characteristics of the ultra-fine powders. The result shows that the ultra-fine powders have different fluidization characteristics from the conventional particles, and this provides basic parameters for the pneumatic separation of iron and phosphorus. Based on the different densities of Fe-rich or P-rich materials, an experimental facility of pneumatic separation can be designed and manufactured, and preliminary make iron and phosphorus separated from the ultra-fine high-phosphorus hematite.

Loading Xinxing Cast Pipe Xinjiang Co Ltd. collaborators
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