CHEMICAL CHARACTERIZATION AND USE OF KILN DUSTS OBTAINED IN TURKISH CEMENT PLANTS

The main source of particulate pollutants in cement factories is the dust originating from the raw meal, rotary kiln and the clinker cooler, the amount of which varies between 3-5 % of the cement. The composition is similar to that of cement, however, the alkali, chlorine and the sulfur levels are generally higher in the dust. In modern cement plants almost all the kiln dust is filtered in bag filters and electrostatic collectors to protect the environment. The purpose of this study is to correlate the compositions of the original raw materials and the kiln dust produced to the type of kiln system and to investigate the usage of kiln dust as a minor additional constituent in producing cement. The raw material and the cement kiln dust samples were obtained from 18 cement plants in Turkey (out of a total of 39) and were analysed in the laboratories of the R&D Institute of Turkish Cement Manufacturers' Association. The results show that if the kiln system has a calcinator (especially with tertiary pipe line) then the respective ratios between sulfur, chlorine and alkali contents of cement kiln dust and that of raw meal increase. Addition of kiln dust as a minor constituent in cement showed the best performance compared with the two other cements containing minor constituents of fly ash and limestone. Among the kiln dust added cements, the strengths tend to increase while sulfur, chlorine and alkali contents decrease.

• INTRODUCTION

• EXPERIMENTAL STUDY

• RESULTS AND DISCUSSION

• CONCLUSIONS

• REFERENCES