Industrial applications and results of low NOx precalciner systems [cement industry]

In the authors´ 1992 IEEE paper entitled “Low NO_x Pyro-systems”, they outlined the design concept of a new calciner generation which allows for the reduction of nitric oxides generated in a rotary cement kiln. Since that time, five industrial installations have gone into operation and another 12 are in some phase of construction. After a brief description of the process and the specific factors governing equipment design, this paper presents the industrial experience gained at several installations operating with a Humboldt Wedag calciner. The present and future development of this technology is also discussed, concluding with comments concerning the important aspects to be considered when applying this new calciner technology