Impact of fast cooling on cement clinker quality in Jiangsu Lvssn cementDate: 2019-06-13 Views:
Each stage is important for cement production, especially the firing and cooling of clinker.
In cement production, we often hear others say that quick firing quench, one of the quench is we scare me in about the rapid cooling, rapid cooling on the quality of cement clinker what impact?
Let's talk about it with an expert in cement known as Jiangsu Lvssn.
1. Fast cooling can improve the strength of clinker.
The strength of clinker can be improved by fast cooling above 1300℃.
Because of high temperature and fast cooling, the conversion reaction of C3S is avoided, and more C3S are retained. Meanwhile, A ore can maintain the crystal integrity and avoid liquid phase melting.
Another benefit of high temperature and fast cooling is that B ore retains high temperature alpha '-c2s.
According to data shows, fast cooling of clinker in the alpha 'type B mineral content is rich, is 40% (B ore percentage), and the slow cooling of clinker, alpha' ore accounted for the proportion of type B is almost zero, the corresponding number of highly active alpha 'type B the existence of mine will no doubt be beneficial to the improvement of the clinker strength, especially for B more of NSP kiln clinker mineral content.
The experimental results show that the faster the cooling speed is, the stronger the cement is.
2. Rapid cooling can reduce the water consumption of standard consistency of cement and improve its compatibility with water reducer.
What we usually talk about in terms of C3A content is actually the potential C3A content is calculated from the chemical composition.
The actual C3A content in the clinker is not only related to the calcination temperature (high calcination temperature, low C3A content), but also related to the cooling speed.
Rapid cooling can make part of C3A and C4AF exist in vitreous body. The faster the cooling speed is, the more vitreous body content is, and the less actual C3A content is.
As the amount of water used for cement's standard consistency increases with the increase of C3A content, rapid cooling can reduce the amount of water used for cement's standard consistency.
In addition, because of the large adsorption capacity of C3A and C4AF, especially C3A, to water reducer, the reduction of C3A can improve the compatibility of cement and water reducer.
The author has studied the influence of different cooling methods on X-ray diffraction peaks of the intermediate phase of clinker doped with composite mineralizer. The results show that the diffraction peaks of C11A7·CaF2 of the intermediate phase of clinker cooled by blast are lower than those of natural cooling, which indicates that the content of C11A7·CaF2 of the clinker cooled by blast is less than that of natural cooling.
Industrial production practice also proves this point.
The results of production practice in the factory show that the diffraction peak of grate cooler C3A is lower than that of multi-cylinder cooler, which indicates that the actual content of fast-cooling clinker C3A is less.
The cooling speed of grate cooler is faster than that of multi-cylinder cooler.
It can be seen that fast cooling is an important measure to ensure the quality of cement clinker, just like calcining at high temperature.