Effect of the Cement Raw Meal Rate Value on SNCR deNOx Efficiency with NH₃ as Reducing Agent

Abstract:

Many complex factors can affect the process of SNCR in cement calciner, and the cement raw meal rate value is a relatively important one. In the present study the influence of the cement raw meal rate value on the SNCR denitration efficiency was investigated in a tubular reactor with a space velocity of 27000 ml/h in the temperature range of 700-1100 °C, and the oxygen concentration was 5% and both the inlet concentration of NO and NH₃ was designed as 1000ppm. The results showed that the denitrification rate of SNCR decreased with the increase of the lime saturation factor (KH) of cement raw meal and increased with the increase of aluminum rate (IM) of cement raw meal at 700~900 °Crecommended that the cement raw meal with low KH, medium silica acid rate (SM) and high IM should be used. In the temperature range of 900~1100 °C the denitrification efficiency of SNCR increased with the KH and decreased with the increase of IM. Based on the experimenyal results it is suggested that the cement raw meal with high KH, high SM and low IM should be adopted.

• Periodical: Materials Science Forum (Volume 944)
• Pages: 1215-1220
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.944.1215
• Online since: January 2019
• Authors: Ya Li Wang*, Nan Li, Hong Zhan Zhang, Su Ping Cui, Yun Ning Zhang
• Keywords: Cement Calciner, Cement Raw Meal Modulus, Denitration Efficiency, SNCR

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