New developments in NOx abatement in the cement industry, Part 2

The German cement industry has played a pioneering role throughout the world in the abatement of NOx emissions. Before any further lowering of limits it is considered necessary that the cement works are allowed sufficient time to minimize NOx emissions so that solutions can be implemented which are economically and ecologically favourable and are best suited to the special features of the particular plant. The mechanisms by which NOx is formed are known. Essentially it is a question of thermal NOx, which is not fuel-specific, so the attempt to link the use of waste fuels for energy recovery with reduced limits for NOx is not logical. For the purposes of process-integrated solutions, which are to be preferred from the ecological and economic standpoints, the evaluation criteria used in Germany for NOx should be changed; a sliding long-term value should be set as the limit in agreement with other countries instead of the short-term limitation. Independently of the present efforts by the cement industry to reduce NOx emissions using the known BAT (Best Available Techniques), the cement industry is also watching the continued development of so-called "emerging techniques". It is considered essential that reliable investigations are carried out in which there is a stepwise transition from pilot plant to demonstration plant and in which the costs are examined and there is a total approach covering all media during the assessment of the particular process.