May 2007 - SIMA

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Figure 3 shows the S-L FBDB gasifiers in Secunda, South Africa. Figure 3 S-L FBDB Gasifiers in Secunda, South Africa The high pressure syngas exiting the Rectisol plant after the S-L FBDB plant contains approximately 85 percent H2+CO, 2.5 percent CO2, and the rest is mostly CH4. The H2/CO ratio is about 1.6, which is the same as used in a natural gas-based MIDREX Plant. In the MIDREX Plant, the cold syngas is first depressurized to about 3 barg by a turboexpander. The low pressure syngas is then mixed with recycled top gas to produce the required reducing gas. The mixed syngas is then heated to over 900º C. The hot gas enters the MIDREX® Shaft Furnace where it reacts with the iron oxide to produce DRI. The reduction reactions are shown below: Fe2O3 + 3H2 —> 2Fe + 3H2O Fe2O3 + 3CO —> 2Fe + 3CO2 The spent reducing gas (top gas) exiting the shaft furnace is scrubbed and cooled, then passed through a CO2 removal system. This reduces the CO2 content to five percent or less, which ensures that the mixed reducing gas (syngas from the gasification plant and recycled top gas from the MIDREX Plant) has an acceptably high reductants (H2+CO) to oxidants (H2O+ CO2) ratio for efficient iron ore reduction. The CO2 removal system will also remove the sulfur gases contained in the recycled top gas. By conditioning the syngas to a quality comparable to the reformed gas produced in a conventional MIDREX Plant and with use of DR-grade iron oxides, the DRI quality will be comparable to that from a natural gas-fired MIDREX Plant. This DRI can be discharged hot and melted in an EAF to produce high quality steels. Expected operating parameters for the combined Gasification/MIDREX complex in India are given in Table I. Table I Gasification/MIDREX Plant Operating Consumptions for Indian Conditions Basis: MIDREX MEGAMOD® with capacity of 1,600,000 tpy of hot DRI 1 S-L FBDB Gasifier using typical high ash Indian coal Input Units Quantity per t hot DRI2 Iron Ore t 1.45 Coal (dry ash-free basis)* t 0.46 Coal (as-received basis)* t 0.84 H.P. steam t 0.7 L.P. steam t 0.1 Oxygen t 0.21 Electricity kWh 180 Maintenance & indirect costs3 USD 10.00 1. The hot DRI product characteristics are: 93% metallization, 2% carbon, and 700º C discharge temperature 2. Quantities are for the combined Gasification Plant and MIDREX DR Plant 3. Includes routine maintenance, long-term amortized cost for replacing. capital equipment, and indirect costs * Values assume typical Indian coal The advantages of the S-L FBDB Gasification/ MIDREX option include: Uses well-proven MIDREX Shaft Furnace Technology: 36 Mt produced in 2006 Ability to use low rank, high ash domestic coals and iron ores Produces DRI with quality comparable to natural gas-based MIDREX Plants MAY-<strong>2007</strong>/4
S-L FBDB Gasification/MIDREX Plant can be paired with an EAF mill to produce high quality long or flat steel products Lower specific capital cost than blast furnace/ BOF No coke, coke ovens, or sinter plant required Reduced air emissions: virtually no SOx or NOx compounds generated Ability to capture high purity CO2 for sequestering or injecting into oil and gas fields Much larger capacities than rotary kilns: up to 2 Mtpy in a single module Better quality product than rotary kilns Midrex is now discussing the use of the S-L FBDB Gasifier/MIDREX combination with several Indian clients. FASTMET® and FASTMELT® Another possibility for iron production in India is rotary hearth furnace (RHF) technology. This includes the FASTMET and FASTMELT Processes. Developed by Midrex Technologies and its parent company Kobe Steel, Ltd., FASTMET uses a rotary hearth furnace to convert iron oxide fines and ferrous wastes into highly metallized DRI. Carbon in the form of coal or contained in the wastes is used as the reductant. Burners fired by natural gas or other hydrocarbons, plus combustion of volatiles, provide the heat required for the reactions. FASTMELT has the same flowsheet through the RHF and adds an electric ironmaking furnace (EIF®) to produce a high quality hot metal from hot FASTMET DRI. FASTMET and FASTMELT Plants can be built in capacities up to 500,000 tpy. A flowsheet is shown in Figure 4. The two technologies have different applications. FASTMET is primarily a means to recycle fine ironbearing materials such as blast furnace dusts and sludges, BOF dust, mill scale, and EAF baghouse dust. This greatly reduces the volume to be disposed of and produces a cost-effective iron product that can be melted in an electric arc furnace, BOF, or blast furnace. In the case of EAF dust, the zinc oxide recovered in the baghouse can be sold to a processor for production of metallic zinc. India has large volumes of steel mill wastes that could be effectively recycled in a FASTMET Plant. If there is not sufficient carbon contained in the wastes, a low volatile coal would be imported for use as the reductant. FASTMELT feeds iron ore fines and iron-bearing wastes and produces a blast furnacegrade hot metal. By controlling the DRI chemistry, the hot metal can be tailored to precisely match the desired chemistry for feeding to an EAF or BOF. FASTMELT hot metal can also be cast into pigs for sale or later use. India has several possibilities for iron ore feed, including screenings from pellet plants and other facilities, and blue dust. FASTMELT requires use of a low volatile, low ash coal that would most likely be imported. Figure 4 FASTMELT Flowsheet The rotary hearth furnace used for FASTMET and FASTMELT has been well proven in operation since 2000 at a significant scale. There are three FASTMET Plants operating in Japan, two of which feed over 200,000 tons per year of steel mill wastes. One of these plants is shown in Figure 5. MAY-<strong>2007</strong>/5
Page 2 and 3: CHAIRMAN P.R. DHARIWAL VICE-CHAIRMA
Page 4 and 5: Introduction SOLUTIONS FOR INDIAN S
Page 8 and 9: Figure 5 FASTMET Plant at Nippon St
Page 10 and 11: CDM potential of waste gases from t
Page 12 and 13: Table - II Details of CERs Issued i
Page 14 and 15: in Secondary steel making process.
Page 16 and 17: Pricing of Natural Gas � Under th
Page 18 and 19: MONNET - FUELING INDIA TO GROWTH Mr
Page 20 and 21: VISIT OF SIMA DELEGATION TO MUSCAT,
Page 22 and 23: MAY-2007/20
Page 24 and 25: SPONGE IRON INDUSTRY IN ORISSA Back
Page 26 and 27: MAY-2007/24
Page 28 and 29: Suresh Thawani becomes the new Mana
Page 30 and 31: MAY-2007/28
Page 32 and 33: S K SARAWAGI & COMPANY PRIVATE LIMI
Page 34 and 35: area of the DRI formed should be mi
Page 36 and 37: • Dust is generated during handli
Page 38: additions and a decrease in electro

May 2007 - SIMA

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