ALC-CH系统在水热处理过程中的物理化学变化 Ⅰ 水热处理温度的影响

PHYSICO-CHEMICAL CHANGES IN ALC-CH SYSTEM DURING THE HYDROTHERMAL TREATMENT INFLUENCE OF TEMPERATURE OF HYDROTHERMAL TREATMENT

采用ＴＧ－ＤＴＡ，ＩＲ，ＸＲＤ和ＮＭＲ对ＡＬＣ（压蒸轻质混凝土）废渣中添加氢氧化钙后的ＡＬＣ－ＣＨ系统，在水热处理过程中的物理化学变化进行了分析，同时用ＢＥＴ方法测定了不同温度水热处理物的比表面积．结果表明，ＡＬＣ渣添加适量氢氧化钙，经１４０～２００℃下水热处理３ｈ的水热处理物中形成了新的水化硅酸钙α－Ｃ２ＳＨ．α－Ｃ２ＳＨ的形成量随水热处理温度的提高而增加．水热处理物的比表面积波动于１２～２２ｍ２／ｇ之间．提高水热处理温度，处理物的比表面积首先随之增大，但超过１６０℃时处理物的比表面积会重新减小．所以，提高水热处理温度将有利于以合成主要含β－Ｃ２Ｓ的贝利特水泥或活性混合材为目的的后续煅烧过程．同时，为了保证水热处理物具有较高的比表面积。

The physico_chemical changes in ALC-CH mixture system during the hydrothermal treatment of temperature from 140 to 200 for 3 h were researched by means of TG-DTA, XRD, IR and 29Si NMR analysis. The changes of the specific surface areas of the hydrothermally treated mixtures in different temperatures were also evaluated by BET determination. The results show that -C2SH is formed when the mixtures are treated in the temperatures above 140 for 3 h. The amount of -C2SH increases with the increase of the treatment temperature. The specific surface areas of the hydrothermally treated mixtures change from about 12 m2/g to 22 m2/g, but will decrease when the temperature is over 160 . Therefore the pretreatment of the ALC-CH mixtures hydrothermally will be favorable to the later sintering process aimed at the synthesis of the -C2S contained cement or additive mixture. Furthermore, it is necessary to select an adequate hydrothermal treatment temperature in order to maintain the higher specific surface a