Research On The Preparation, Performance And Application Of Ultra-fine Fly Ash In Cement Slurry

The ultrafine fly ash has good chemical activity,morphological effect and micro aggregate effect.The production cost is low.The ultrafine fly ash is becoming a admixture which is widely used for high performance cement concrete.But at the moment,superfine fly ash in the research and application in cement slurry is less.While cement slurry is very different from high performance concrete in using environment,performance requirements and the structural components,with the help of the existing research results and combined with the cementing engineering characteristics,and the analysis and comparison of ultrafine fly ash used in both the differences,the physical and chemical performance of ultrafine fly ash can be improved.Then the ultrafine fly ash can be applied to design irregular density cement slurry system,which has very important significance.The article determined that the secondary fly ash of Zhu Cheng company had a better quality through experimental optimization.It couble be used as raw materials for the preparat--ion of ultrafine fly ash.Ultimately three different particle size of ultrafine fly ash FA2,FA1 and UFA were obtained by using half a grinding process.By studying on ultrafine fly ash particle size distribution,particle morphology,mineral composition,and the influence of ultrafine fly ash for rheological properties and compressive strength performance of conventional density cement slurry,finally the article determined that UFA has the best comprehensive performance.But its performance was still insufficient.Compressive strength and content limits need to be perfected.According to the principle of composite material and theory of high packing,the paper selected slag and sepiolite to improve the performance of superfine fly ash and they could played a complementary effect.Finally the experiment determined the best proportion of UFA,slag,sepiolite is 3:4.125:0.375.The paper also obtained enhanced materials which was called UB,with a diameter of 6.33 microns.According to the principle of design of concrete technology,The article designed the density of 1.2 g/cm3?1.4 g/cm3 of high-strength and low-density cement slurry and a density of 2.6 g/cm3 of high temperature and high density cement slurry by using reinforced materials UB.Various properties of two kinds of slurry system were evaluated respectively.The experimental results showed that the high strength and low density cement slurry had the flow of excellent performance,retrogradation,and cement compressive strength developing fast,strength of 48 hours all over 14 mpa.Permeability of cement stone was extremely low.Thickening transition time was short.Cement slurry system had a good comprehensive performance.High temperature and high density cement slulrry had high fluidity,low water cement ratio,settlement of good stability and compressive strength of 24 hours more than 14 mpa.Thickening transition time was also short.The high temperature and high density cement slurry system had a good comprehensive performance.