sponge iron industry –past-present-future - SIMA

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advantages over the conventional heavy media cyclones. It is an ideal technology for the high ash & high NGM Indian coals. The Tri-Flo ® has a very high sink capacity and produces three products in one vessel, thus improving separation efficiency, simplifying plant layout i.e. requiring less space and reducing overall capital costs. Additionally, in this system the material is fed at an atmospheric pressure separately from the dense medium. This results in very low wear & tear compared to conventional heavy media system and thus resulting in reduced overall operating costs. The Tri-Flo is a proven technology with more than 30 nos. commercial plants operating worldwide mainly in mineral processing. This technology is now attracting the interest of coal beneficiation plant operators and designers due to its unique features that better deal with the problems posed by modern coal mining methods, lower run-of-mines (ROM) quality and rejects rewashing. The Indian non-coking coals have a very high range of quality variation in feed. The Tri-Flo ® Technology with a double stage separation can better adapt to the Indian coals and provide a more consistent product at higher yields with reduced wear & tear and thus resulting in better plant availability. Allmineral | Asia having additionally dry jigging technology (Allair ® ) and wet jigging technology (Alljig ® ), has already made deep in roads into the Indian Mineral beneficiation market. With the Tri- Flo ® technology in its bag, it is the only company in India to offer such a varied range of technologies to the Indian coal and minerals <strong>industry</strong>. Advantages of Tri-Flo Technology The Tri-Flo technology has numerous advantages over the competitors’ technologies. Advantages are reported below. Two, Three, or More Product from One Vessel The Tri-Flo is a multistage separator in one vessel with reduced capital cost (buildings, piping, etc.) and operating cost, if compared with the same multiple density traditional circuit. The Tri-Flo rewashes the float stream of the previous stage where the separation is repeated and operates like a rougher- cleaner in coal preparation or as a rougherscavenger in ore separation. The second or following stage can be: l A final bye-product (i.e. premium coal, power plant coal, and rejects) l Comminuted to improve the liberation and reprocessed for increased recovery l Re-circulated to head feed for sharper separation in difficult applications Energy cost of pumping is reduced by up to 50% if compared with traditional double stage installations. Reprocessing the Float Material Gives Better Results Than Reprocessing the Heavy Material Tri-Flo - Heavy material must travel from the centre to the wall of the separator to be discharged and the misplaced coal to rejects is minimal. On the contrary the float is discharged from the centre of the separator on the same axe where it is fed and might contain some misplaced heavy material due to various reasons (overloading the separator, changed conditions in the feed characteristics, etc.). In case of overloading of the first stage, the second stage is fed with the first stage light material and the majority of the heavy material has been already rejected, making the conditions in the second stage more stable and allowing to reject the misplaced material. Other Technologies – Other technologies, derived from the British Coal Board (Larcodems and similar) have the possibility to rewash the heavy material in a second stage. If the first stage is overloaded low quality light product is produced and lower densities are required to obtain the target product misplacing to rejects the more profitable premium coal which will be discharged as power plant product with significant economical losses as proved in many applications. Reprocessing the light material gives better overall performance because each size fraction is separated at more or less the same density, instead reprocessing the heavy material provides density cuts that are progressively higher as the particle size decreases with obvious economical losses . JANUARY-2011/34
Only the Medium is Pumped Reduced wear of the Heavy Medium feed pump and following piping – typical life time is doubled if feed is not pumped. Higher plant availability due to reduced blockages of piping and pump. The feed material remains into the slurry for a very short time as opposed to conical cyclones. Lower degradation of the feed material and products with following savings in water treatment. Minimal Contact of the Material with the Separator Wall Tri-Flo - The feed enters the separator at atmospheric pressure along the center of the separator, light material floats along the central axe, highly abrasive heavy material quickly reports to the wall and is discharged through the sink head positioned near the feed inlet. Cyclones – The feed is pumped with the separating medium and enters tangentially the separator near the light material outlet (vortex finder). Heavy and highly abrasive material rotate and wears the separator from the feed point all the way down to the opposite side where the sink outlet (spigot) is positioned. Improved Hydrodynamics Inside the Vessel The flow patterns inside cylindrical vessel is improved in comparison with more uniform centrifugal acceleration and a wider region of zero axial velocity particularly useful for difficult / high near gravity separations (high amounts of material of specific gravity near the separation gravity which is very common in India). High Sink Capacity The Tri-Flo technology has the highest sink capacity on the market for both the first and second stage allowing for wide variations in feed characteristics. Conical cyclones are notoriously sink limited. Larger Feed Top Size The Tri-Flo technology can accept larger particles than conical cyclones if comparing the same vessel diameter. This means that in smaller scale applications with acceptable coal liberation: l a single circuit (Tri-Flo) can operate the separation saving on the coarse coal circuit (static bath or jigs) l It is not necessary to reduce the feed top size to fit the vessel diameter As an example, assuming a 200 t/h application with good liberation at top size of 75mm. A single 700 mm Tri-Flo can be installed, if a cyclone is installed for the capacity a 750 mm should be chosen but the feed material must be crushed at top size of 50 mm. As an alternative, to accommodate a top size of 75 mm a 1000 mm should be installed. In both cases, the economical savings offered by the Tri-Flo are significant. Fine Media and Media Segregation Acceleration forces are necessary for the separation. Also the fine ferromagnetic powder used for the medium has the tendency to separate and the density of the sink medium is higher than the density of the float medium. This difference is called differential. If the differential is too high the separation sharpness is compromised and a finer medium shall be used. Finer medium is more expensive and more difficult to recover, hence the operational cost is higher. Cylindrical cyclones show lower differentials if compared with conical cyclones allowing coarser and less costly powder to be used. DynaFeedä System The patented DynaFeedä system allows sharper separation in the following separator. The more difficult the material to be processed the higher the advantages obtained with the DynaFeed system. Obviously, the DynaFeed system gives significant advantages with fine material (-4 mm) which is more difficult to process. During initial testing on a difficult separation, clean coal yield was increased as much as +25% if compared with the same separator operating without the DynaFeed system. JANUARY-2011/35
Page 2 and 3: CHAIRMAN V S BAPNA VICE CHAIRMAN B
Page 4 and 5: UPGRADING QUALITY OF INPUTS TO AUGM
Page 6 and 7: There is acute shortage of high gra
Page 8 and 9: SUCCESSFUL STARTUP AND OPERATION OF
Page 10 and 11: GSPI Micro-Module Control Room Gulf
Page 12 and 13: SPONGE IRON INDUSTRY -PAST-PRESENT-
Page 14 and 15: JANUARY-2011/12
Page 16 and 17: From a meager production of 1.31 mi
Page 18 and 19: tubes. The newly reformed gas, cont
Page 20 and 21: Process Advantage l Proven performa
Page 22 and 23: Annexure I Map of Natural Gas pipel
Page 24 and 25: SIMA DELEGATE TO CHIN JANUARY-2011/
Page 30 and 31: CONTRIBUTION OF SECONDARY STEEL SEC
Page 32 and 33: in total crude steel production wou
Page 34 and 35: New product developments Sabyasachi
Page 38 and 39: Description “Graspan Tri Flo ® P
Page 42 and 43: Moreover, some analyst suggest that
Page 44 and 45: BRIEF REPORT ON ONE DAY SEMINAR ON
Page 46: JANUARY-2011/44

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