Fuel Savings and Reduced Emissions: Experience From 80 Oxy-fuel Installations in Reheat Furnaces

摘要

Eliminating the nitrogen ballast in the combustion and heat transfer process by replacing the air with industrial-grade oxygen cuts fossil fuel consumption by up to 50 percent and reduces CO_9 levels correspondingly. Further reduction of fuel and CO_2 is possible through the use of low-caloric energy forms, as acceptable flame temperatures can be achieved with oxygen. NOx levels can also be kept low, as there is no nitrogen in the oxy-fuel combustion process. Furnace control is good, and the flame temperature of modern oxy-fuel burner technology is lower. Furnace throughput can be boosted by up to 50 percent, providing extra production capacity, which can be used to concentrate production and better accommodate peak volumes and maintenance activities. Oxy-fuel installations are powerful and space-efficient and are thus easy to retrofit in any existing furnace, requiring less maintenance compared to air-fuel systems with ventilator fans, bulky flue gas systems and recuperators. Oxy-fuel technology is no longer simply a well-known means of improving steelmaking. Since 1990, Linde has proved in more than 80 installations the viability of oxy-fuel technology in creating effective total cost solutions in applications for reheat furnaces and annealing lines.