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Show reducing residence time, improving product quality) that will improve the competitive posture of natural gas in future steel reheat applications. The urgency of such research and development is dictated in part by the lead time necessary to achieve commercial readiness of a technological innovation (such as hot charging or thin strip casting) and by the willingness and ability of the u.s. steel industry to adopt the innovation. Although the u.s. steel industry has been slow to adopt new technologies in the past, findings indicate an increased willingness to consider new technologies that will improve the U.S. steel industry's position in both domestic and international markets. Therefore, it is likely that technological changes will be implemented during the next 20 years that, in the absence of significant natural gas reheat technology innovat ion, could dramatically al ter the natural gas reheat market. Extensive interviews with selected steel industry representatives were conducted during the course of this study to elicit suggestions for steel reheat R&D. Many of these suggestions a~dressed natural gas combustion fundamentals and improved furnace design. The most frequently mentioned R&D needs associated with natural gas-fired steel reheat fall into the following categories: • Furnace design and combustion fundamentals • Sensors and controls • Information transfer. (See Table 5.) In general, the steel industry is open to any developments that would lower its operating costs. It is also receptive to any developments that would favor the use of gas over other fuels, as long as it can maintain dual-fuel capabilities in the event that gas prices increase substantially or curtailments occur. The gas industry can capitalize on this receptiveness by pursuing selected steel reheat R&D that will enhance the competitive position of natural gas. Table 5 - Steel Reheat R&D Needs Pertinent to Natural Gas Use Furnace design • Improve recuperation technologies and burner designs • Develop improved gas technologies adaptable to steelmaking processes in which there is little or no reheat (i.e., quick reheat furnaces designed for hot charging or equalization heating capable of handling thin cast steel) • Investigate Japan's 100-meter walking beam furnaces for preheating steel • Investigate hybrid combination of electric induction and gas reheat technologies (gas is more efficient for large temperature changes up to 1,500°F, where induction is more efficient for small changes) • Design new methods for handling slabs on edge for close side firing • Design improvements in scale-free heating • Development and testing of pulse-fired technologies • Design new, more efficient furnaces (e.g., improved refractories, new alloys and components to get rid of water-cooled beams) • Develop ways to put energy directly into steel • Design high temperature recuperation in the range of 1,700°F-I,800°F • Investigation of regenerative burners in continuous reheat furnace applications Combustion fundamentals • Develop firing methods for achieving reheat temperatures without NOx problems Combustion fundamentals (continued) • Test pulse jet combustion • Research flame dimensions/characteristics as a function of several parameters, such as fuel flow rates and burner designs Sensors and controls • Develop computerized combustion models for online control • Develop better sensors and controls (e.g., ultrasonic sensors for reading slab temperature profi les ) • Develop instrumentation to allow quicker response • Develop automatic controls that can withstand the harsh environments of a steel mill • Develop improved combustion analysis technologies (i.e., 02 analyzers that require less maintenance, are more accurate, and last longer) • Develop better heat control methods for batch furnaces Information transfer • Develop computer simulation models for off-line "what-if" analyses (e.g., what happens if the refractory brick is changed?) • Compile data on pressure control, refractory linings, and recuperation in a condensed and usable form (not like a publicity bulletin) • Improve communications between the gas industry and the steel industry 300 |