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The paper presents an overview of the main results of the work carried out in the frame of project 'CO2 reduction in reheating furnace' or CO2RED started in July 2006 with a financial grant from the Research Fund for Coal and Steel (RFCS) of the European Community. The themes of highly efficiency combustion technology and low emissions have been addressed in the past facing with the limitation of conventional flame combustion technology both for air and oxy fuel burner. In the present project many well known potential drawbacks (NOx emissions, reliability, control, etc) which limited a wide diffusion of the regenerative and oxyfuel technology are faced with a specific technological solutions such as flameless technology. Both using regenerative technology and oxy-fuel it was evaluated: 1) an increase of production of about 20% thanks to the installation of burners also in the zone usually used as the tunnel in traditional furnaces; 2) the same production with a furnace length which is 20% less than the original, a 5% capital cost reduction due to the reduction of length and piping, and energy consumption and consequently CO2 emission (about 7-10%). Pilot trials have proven that, with a constant burner power, reheating rate with pure BFG-oxyfuel was slower than propane-cold air combustion. Therefore with the present technology BFG should always need a booster fuel like propane, natural gas or coke oven gas if the goal is the same productivity of high heating value gaseous fuels. In order to increase thermal efficiency and consequently productivity with BFG and take advantage of low energy costs and low emission (in case BFG-related CO2 is considered a 'non emission') the only way is the fuel preheating. Nevertheless further work is required in order to develop gas preheater systems (regenerator or gas-gas heat exchanger) to couple with both air and oxy-fuel combustion technology.