應用化學摻料於水泥研磨製程之助磨成效研究

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

陳奇鴻(Chi-Hong Chen)

指導教授 ： 李釗

國立中央大學/工學院/土木工程學系/碩士(2006年)

摘要

生料配料與研磨、熟料燒成、水泥研磨等為水泥的三大製程，其中水泥研磨的重點在於提昇水泥成品的性質及降低電耗。為使熟料更具易磨性，一般會在水泥研磨製程中添加助磨劑。由於水泥生產設備已漸為大型化，若助磨劑使用不當，對以強度為重要評估指標的水泥產品將會影響既深且遠。
在研磨過程中加入助磨劑，除可阻止熟料受機械作用而形成的微裂縫癒合以避免做虛功外，並可與水泥熟料粒子的表面電荷產生中和作用以避免結團。由於各種化學摻料的成份均不相同，為瞭解其是否達到「助磨」成效，本研究以實驗室用球磨機進行試驗，並測定水泥粉體之比表面積、留篩率、流動性等性質，作為助磨劑效益的判定。
試驗結果顯示，當F型強塑劑與G型添加量為0.055 %，流動化劑與四號助磨劑為0.015 %時，能夠有效提昇比表面積，且減少研磨時間約11 ~ 13 %。在雷射粒徑分析結果部份，亦能增加成品中30 ~ 40 μm顆粒的含量，進而提高新拌水泥漿體的流動性以及硬固漿體的抗壓強度。因此在適量添加化學掺料下，能夠增進水泥成品的性質。

關鍵字

比表面積 ； 助磨劑 ； 化學摻料 ； 水泥 ； 研磨

並列摘要

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.

並列關鍵字

grinding aids ； cement ； grinding ； specific surface area ； chemical admixtures

參考文獻

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