Iron & Steel Production & Processing – Melting & Casting
Gases for Melting and Casting in Iron and Steel Production Technologies include: oxygen fuel (oxy-fuel) and oxygen-enhanced (air/oxy-fuel) combustion systems; nitrogen and argon blanketing (shrouding / inerting); stirring using gases; and other industrial gases applications. These offer significant financial benefits for preheating, melting, holding and casting in the iron and steel production industry. Offerings applicable to:
Blast Furnaces (BF) Direct Reduced Iron (DRI) Basic Oxygen Furnaces(BOF) Electric Arc Furnaces (EAF) – Ladles or Torpedo Cars Holding Furnaces Continuous Casting or Ingot Teeming Blast Furnace (BF) – Blast Enrichment Oxygen is injected into the blast furnace to increase production rate and to support the combustion of alternative fuels. The cost of oxygen is offset against fuel savings. Blast Furnace (BF) – BF Blowdown Back to top
Direct Reduced Iron (DRI) – Oxygen Enrichment Oxygen is injected into the furnace to increase productivity, reduce flue gas volume and allow a more stable flame. The cost of oxygen is offset against fuel savings. Back to top Basic Oxygen Furnace (BOF) – Oxygen Blowing The Basic Oxygen Furnace is a highly efficient item of equipment for converting pig iron into steel by injecting oxygen. Air Products can supply the gas, advanced flow and process control systems and technical expertise (in, eg, positioning of lances).
Basic Oxygen Furnace (BOF) – Scrap Preheating Complete burner and control packages have been developed to efficiently preheat ferrous scrap using non-water-cooled oxy-fuel burners. 70% fuel savings and 50% reductions in heat-up rates are typical. Basic Oxygen Furnace (BOF) – Slag Splashing By injecting nitrogen down an existing BOF oxygen lance to splash a protective coating of molten slag on the inner refractory wall, gunning consumption is considerably decreased and campaign life extended. Basic Oxygen Furnace (BOF) – Bottom Stirring The melt is stirred by using high-pressure gas injection to improve steel yield and alloy recovery, and extend campaign life. Back to top JetBOx Chemical Energy System for Closed-door EAFSteel making Overview Brochure – Tell me more An Improved Method of Applying Chemical Energy into the EAF Presented by Air Products and PTI at EEC 2002 in Venice
Electric Arc Furnace (EAF) – Oxy-fuel Assisted Melting The electric arc method of melting metal is inefficient until a flat bath is achieved. By using a fuel-efficient oxy-fuel flame at the beginning of the melting process, a greater overall melting efficiency is achieved with a faster melt rate. Further temperature homogeneity benefits can be achieved by using these burners to direct thermal energy at cold spots caused by uneven energy distribution from the electrode arcs. Additionally, the burners can be positioned in front of the slag door to enable early, efficient oxygen lancing, or over the tap hole area to promote quick, trouble-free tapping. Electrical savings of 80kWh/tonne and 20% production increases have been achieved.
Electric Arc Furnace (EAF) – Foaming Slag Practice Lances are hydraulically manipulated through the slag door to inject oxygen, carbon and lime into the surface slag layer during the electric arc melting process. This action decarburises the melt and aids formation of an insulating foamy slag layer which decreases heat loss from the melt surface and therefore reduces energy costs. Electric Arc Furnace (EAF) – Post-Combustion
Oxygen is injected into the post-combustion zone of electric arc furnaces to promote combustion of carbon monoxide inside the furnace rather than in the off-gas handling system. This reaction produces heat that is transferred to the charge, reducing energy consumption (typical electrical savings of 10-20 kWh/tonne) and increasing productivity by up to 4%. Additionally the post-combustion injectors reduce loading on the EAF baghouse and improve environmental compliance with respect to carbon monoxide. Back to top
Ladle or Torpedo Car – Preheating Complete burner and control packages have been developed to efficiently preheat ladles or torpedo cars using non-water-cooled oxy-fuel burners. 70% fuel savings and 50% reductions in heat-up rates are typical. Ladle or Torpedo Car – REHeat heating
Our patented technology (with Bethlehem Steel) for chemically reheating steel by simultaneous injection of fuel (aluminium and silicon) and oxygen achieves temperature gains of 5 to 8°C/min. Subsequent stirring with inert gas ensures that steel cleanliness is not adversely affected. This technique is used to reheat cold ladles or torpedo cars of metal to avoid expensive pourbacks and subsequent casting interruptions. Back to top
Holding Furnace – Inerting Using nitrogen to displace the oxygen in a holding furnace atmosphere reduces the formation of oxides at the melt surface providing a higher yield and improved quality. Holding Furnace – Pressurising Nitrogen can be used to pressurise the holding furnace for greater control during tapping. Back to top
Continuous Casting or Ingot Teeming – Clean Cast Argon Shrouding Shrouding molten metal streams with an inert argon atmosphere minimises oxide and nitride formation to decrease alloy wastage, reduce production rejects and increase product quality. Typical applications are ladle-to-tundish, tundish-to-mould and ingot teeming processes.