Developments in gas-fired industrial heating processes for the new millennium

For many years the UK gas industry has developed and promoted gas technologies for low and high temperature applications, which reduce energy consumption. This issue is still important today with a commitment by European Union, through the member states, to reduce carbon dioxide emissions. However, these improvements in efficiency must also be achieved without increasing other controlled emissions, or reducing the output from the installation. The paper covers a range of natural gas technology, focusing mainly on high temperature processes, which are available now or being developed to meet these new challenging requirements. The technologies discussed include low-NOx versions of recuperative and regenerative burners, gas-fired rapid heating systems, flameless oxidation, oxygen enrichment, advanced catalytic combustion, electronic air/fuel ratio control and bilinear furnace controls. The development of hybrid systems such as a gas-fired preheater for an electric induction furnace is also discussed. In addition to these technologies, background support activities such as experimental and mathematical modelling are also described. Of particular interest are recent developments in the use of zone-type furnace and boiler models, which now run on PC computers in a mater of seconds.