The research regarding efficiency of grinding process of cement with applie chemical admixture

Autor: Chi-Hong Chen, 陳奇鴻
Rok vydání: 2006
Druh dokumentu: 學位論文 ; thesis
Popis: 94
The mixing and grinding of raw materials, the burning of clinkers and the grinding of cement are the three manufacturing procedures of cement, in which the last one is to enhance the characters of cement and save electricity. Due to the more and more large-scaled manufacturing facilities, the improper use of grinding aids can prominently affect the strength, as the significant indicator of cement products. Mixing grinding aids during grinding can not only prevent the close up of microcracks that are resulted from the manufacturing procedure of clinkers in machines, but also neutralize the surface electrical charge of clinker particles of cement without clustering. In order to understand the grinding effectiveness of the different elements of each chemical admixture, the study adopts a ball mill, measuring the specific surface area, amount retained ratios and flowability of cement powder to assess the effectiveness of the grinding aids. According to the experiment, the increase of F and G superplasticizers to 0.055 % and that of fluid medicaments and grinding aids No. 4 to 0.015 % can raise the specific surface area effectively and reduce the grinding time to around 11 ~ 13 %. As for the laser grain size analysis, the grains of end products are increased to 30 ~ 40 μm as well. The result enhances the fluidity of the new cement paste and the compressive strength of the hardened paste; mixing the proper amount of chemical admixtures, therefore, can enrich the characters of cement products.
Databáze: Networked Digital Library of Theses & Dissertations