Study On Modification And Application Of Triethanolamine Cement Grinding Aids

In the process of cement production, a huge number of energy is used in the aspect ofcement grinding, but this part of energy’s utilization is low. The use of cement grinding aidsis the most simple and effective way to improve the grinding efficiency, because of theadvantage of using grinding aids, such as less investment, working fast and improving thequality of cement. At present, most of the cement grinding aids in the sale are the complexesof organic compounds including alkanol amines and polyhydric alcohols such astriethanolamine, triisopropanolamine, ethylene glycol, and so on. Triethanolamine, a wakebase, with the ability of chelating with certain metallic ions in highly alkaline media, irstlyused as Early Strengthen Agent in cement industry, can improve the early strength of cementeffectively, but make the late strength declined. Triethanolamine equipped with polyhydricalcohols as cement grinding aids makes grinding easy, but the cost is high fortriethanolamine’s high price.The paper aimed to develop a new modified triethanolamine complex cement grindingaid with high effect to solve the problems faced by triethanolamine grinding aid, through themodification of triethanolamine for better grinding effect and strengthen effect, compoundingcomplex cement grinding aid with better modified triethanolamines and the study of theirperformance systematically under the same conditions including the grinding process and themixing amount.Six kinds of modified triethanolamine, named from S1to S6were synthesized at alaboratory stage. Their performance as cement grinding aid and the action mechanism wasdiscussed under a certain grinding time and mixing amount, through juxtaposing specificsurface area and the early and later strength of the cement mortar. It was found that, S1、S2、S3and S4had better grinding effect and strengthen effect, the specific surface area increasing11.14%,8.00%,12.00%and7.11%,28d strength increasing3.28%,3.78%,5.08%and5.41%,and the shorter, the more and stronger the polarity of the modified groups, the better thegrinding effect and strengthen effect.Three kinds of modified triethanolamine complex cement grinding aids, GA2, GA3andGA4, were compounded according to a certain formula, using S1, S2and S3as triethanolamine. Compared there grinding effect and strengthen effect with bland and GA1,the triethanolamine complex cement grinding aid of the same formula, we found that, GA3and GA4were better, increasing the specific surface area more than20m~2/kg,3d strength1MPa～2.5MPa and28d strength4MPa～8MPa. What’s more, the influence of thesecomplex cement grinding aids on the water requirement of normal consistency, setting timeand stability was very small, and therefore the construction was not affected.