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Drying and preheating processes of iron ore pellets in a trav-eling grate, ... A field test was systematically carried out in a traveling grate. The effects of pellet diameter, moisture, grate ...
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The objective of this paper is to optimize the parameters of pellet drying and preheating process in grate. A mathematical model of drying and preheating is developed, and is verified by the experiments. Further, the operating parameters of wind temperature, wind speed, grate speed and bed depth etc. are investigated through the …
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The thermal state of iron ore pellets during traveling-grate processes is complex, and sintering is a complex coupling process involving multiple physical factors. In this study, the temperature distribution during updraught drying (UDD) is investigated using computational fluid dynamics (CFD) and orthogonal testing. Based on the calculated …
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The grate kiln process was developed by former Allis Chalmer and the first plant on this technology was constructed in 1960. In the grate kiln process (Fig 3) the traveling grate is used to dry and preheat the pellets. Material moves on straight travelling grate till it attains the temperature in the range of 800 deg C to 1000 deg C.
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In the Grate-Kiln process (Fig 3) the traveling grate is used to dry and preheat the pellets. Material moves on straight travelling grate till it attains the temperature of 800C to 1000C. Thereafter it is transferred to …
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process units connected in series: a traveling grate for drying and preheating green balls, a rotary kiln for indurating preheated pellets, and an annular cooler for cooling the fired pellets.
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Abstract: A mathematical model of drying and preheating processes in a traveling grate was presented based on the laws of mass, momen- tum, heat transfer, and drying semiempirical relations.
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Fig. 1 Main scheme of the grate-kiln induration process [23] To produce iron ore pellets following materials were used: magnetite concentrate, dolomitized limestone, and bentonite ( Table 1 ...
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The straight-grate induration furnace is a non-catalytic packed bed reactor having cross current flow of gas-solid media. Different physio-chemical phenomenon occur during pellet bed traveling on the grate like drying and condensation of free surface moisture, combustion of carbon or coke particle, calcination of limestone, LOI or …
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A mathematical model of drying and preheating processes in a traveling grate was presented based on the laws of mass, momentum, heat transfer, and drying s Drying and preheating processes of iron ore pellets in a traveling grate | SpringerLink
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oped the drying and preheating process models of iron ore pellets induration. Also, the models of straight-grate have been developed [7-11]. Recently, a model of the induration process has been developed by taking the variations of pellet porosity and bed shrinkage into account. Barati demon-strated the validity of the assumption that the ...
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Abstract: A mathematical model of drying and preheating processes in a traveling grate was presented based on the laws of mass, momen- tum, heat transfer, and drying …
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Drying and preheating processes of iron ore pellets in a traveling grate. Article. ... The thermal state of iron ore pellets during traveling-grate processes is complex, and sintering is a complex ...
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A field test was systematically carried out in a traveling grate. The effects of pellet diameter, moisture, grate velocity, and inlet gas temperature on the pellet bed …
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So, the pellet drying and preheating process in grate is a highly interactive multivariable process with strong nonlinearities and dissimilar dynamics [5][6][7][8][9][10][11][12][13][14] [15] [16 ...
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In China, iron ore pellets are mainly produced using the grate-kiln process. The grate-kiln process is composed of three separately subparts: the traveling grate, the rotary kiln and the cooler [3]. The traveling grate is adopted primarily to dry and preheat green pellets for feeding into a rotary kiln [4].
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's traveling grate pelletizing plant is the industry's leading induration technology for iron ore pellet production for a wide range of plant capacities. Based on over 60 years' experience and world-class R&D, our process produces uniform pellets and ensures high performance and quality, with low investment and operating costs, as well as ...
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In this paper the process parameters,such as bed depth of grate,gas temperature of updraught drying and downdraught drying,temperature and velocity of preheating gas in production of oxidized pellets through grate-kiln,were studied by preheating grate simulator.Self-produced magnetite concentrates from Chengchao Mine, with 1.0%1.2% …
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Pelletizing is the process of transforming iron ore fines into spherical pellets through agglomeration and induration to be used as feed to a blast furnace or direct reduction …
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J.X. Feng et al., Drying and preheating processes of iron ore pellets in a traveling grate 537 3.2. Governing equations (1) Gas energy conservation equation To deduce the heat exchange equation in ...
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A mathematical model of the grate/kiln process for the induration of iron ore pellets, verified for an operating plant, has been used to investigate the effects of process variables on fuel and ...
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Traveling Grate, the Rotary Kiln, and the Annular Cooler. Independent variable speed control of drying/preheating, induration, and cooling allows process flexibility to adjust to changes in concentrate feed. The traveling grate is used primarily to dry and preheat green balls for feeding into the rotary kiln, where they are indurated.
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1. 1 Grate and process flow The main function of grate IS for drying and preheating of the green pellets. The grate is divided into four zones: up-draught drying …
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This work analyzes the heat transfer conditions in a rotary kiln used for the heat treatment of iron ore pellets in the grate-kiln process. The analysis concerns conditions relevant to fuel switching from coal to hydrogen gas. A modeling assessment of the radiative heat transfer in the kiln is conducted including the pellet bed and inner kiln …
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30 Preheating of Pellets In the grate kiln process preheating zone is 400-1100˚C. During preheating process several reactions take place such as decomposition of carbonates, sulphates, hydrates etc. In this process oxidation of magnetite takes place to hematite 2Fe3O4 +½O2 = 3Fe2O3 Fresh crystals of hematite provide very strong bonds to ...
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A technology assessment checklist that investors should consider when making a new pellet plant investment decision is presented. Schematic of the straight grate pelletizing process. Thermal ...
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Iron ore pellet is widely used in iron and steel smelting due to the high strength, the high productivity and the low energy consumption [].Chain grate is an important equipment for drying, preheating and enhancing the strength of pellets, and it is mainly composed of four parts: updraught drying (UDD), downdraught drying (DDD), …
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Ferrexpo and Outotec have a long history of collaboration. Outotec's predecessor, Allis Chalmers, delivered the first two grate kiln (GK) pelletizing plants to the Poltava mine in 1976. The plants, with a rated capacity of 3 Mtpy, included a so-termed traveling grate for drying and preheating green ball iron ore pellets, a …
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A dynamic mathematical model of the complete grate/kiln iron–ore pellet induration process. J. Thurlby. Materials Science. 1988. Induration (drying and hardening) of iron ore pellets is an energy-intensive feed preparation step for both the blast furnace and direct reduction routes to iron.
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Abstract The quality of the iron ore pellet and the yield of its drying process are directly affected by the drying con-dition. Such conditions are complex to be predicted or measured due to the heat and mass transfer process of the pellet in chain grate. However, it is difficult to measure the temperature and drying rate of the pellets ...
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