In this paper, the cement clinkers from various industrial Kilns were investigated by a superposing peaks method for X-ray quantitative analysis (XRQA) of clinker minerals, the results show that the clinker mineral co...In this paper, the cement clinkers from various industrial Kilns were investigated by a superposing peaks method for X-ray quantitative analysis (XRQA) of clinker minerals, the results show that the clinker mineral contents measured by XRQA method better accord with the reality of clinkers made in different conditions than theoretic contents calculated by Bouge formula do. The measured contents of C3S of clinkers manufactured in rotary kilns are higher than theoretically calculated values,whereas, the results of clinker man manufactured in shaft kilns are contrary to that. This is because in rotary kiln, the raw meals are fully pre-heated and have high sintering temperature, the clinkers are well solid-solutioned and rapidly cooled,on the contrary,owing to the struetural defects, it is easy to exist reducing atmosphere and lower temperature in shaft kiln,moreover the cooling rate is slower, all these can evidently Lead to worse clinker quality. Adding CaF2-Ca-SO4 complex mineralizer can remarkably modify the sintering situation in shaft kiln ,especially can evidently increase C3S content and make it well crystallized, therefore, im prove the sintered quality of clinker.展开更多
Emission pollution and prevention measures of Pb during cement calcination were discussed. The content of Pb and the variation of composition were explored by means of atomic absorption spectroscopy （AAS） and X-ray ...Emission pollution and prevention measures of Pb during cement calcination were discussed. The content of Pb and the variation of composition were explored by means of atomic absorption spectroscopy （AAS） and X-ray diffraction. The results show that a number of Pb emits during cement calcination, F and Cl promote the emission of Pb, and Pb is enriched in kiln dust. The smaller the particle of kiln dust, the higher the content of Pb. When utilizing the raw materials with a high content ofPb, a more efficient dust collector should be used and the kiln dust should be used as the addition of cement. Pb in clinker is enriched in the intermediate phase. The reduction of silica modulus is useful to increase the solidification content of Pb in clinker. The solidification content of Pb in calcium sulphoaluminate mineral is higher than that in calcium aluminate mineral.展开更多
文摘In this paper, the cement clinkers from various industrial Kilns were investigated by a superposing peaks method for X-ray quantitative analysis (XRQA) of clinker minerals, the results show that the clinker mineral contents measured by XRQA method better accord with the reality of clinkers made in different conditions than theoretic contents calculated by Bouge formula do. The measured contents of C3S of clinkers manufactured in rotary kilns are higher than theoretically calculated values,whereas, the results of clinker man manufactured in shaft kilns are contrary to that. This is because in rotary kiln, the raw meals are fully pre-heated and have high sintering temperature, the clinkers are well solid-solutioned and rapidly cooled,on the contrary,owing to the struetural defects, it is easy to exist reducing atmosphere and lower temperature in shaft kiln,moreover the cooling rate is slower, all these can evidently Lead to worse clinker quality. Adding CaF2-Ca-SO4 complex mineralizer can remarkably modify the sintering situation in shaft kiln ,especially can evidently increase C3S content and make it well crystallized, therefore, im prove the sintered quality of clinker.
基金the National Natural Science Foundation of China(No.20377014)
文摘Emission pollution and prevention measures of Pb during cement calcination were discussed. The content of Pb and the variation of composition were explored by means of atomic absorption spectroscopy （AAS） and X-ray diffraction. The results show that a number of Pb emits during cement calcination, F and Cl promote the emission of Pb, and Pb is enriched in kiln dust. The smaller the particle of kiln dust, the higher the content of Pb. When utilizing the raw materials with a high content ofPb, a more efficient dust collector should be used and the kiln dust should be used as the addition of cement. Pb in clinker is enriched in the intermediate phase. The reduction of silica modulus is useful to increase the solidification content of Pb in clinker. The solidification content of Pb in calcium sulphoaluminate mineral is higher than that in calcium aluminate mineral.
