石灰石流态化煅烧探索研究

Exploratory study on fluidized calcination of limestone

为了高效回收利用废弃石灰石资源,对粒径为0.5～1 mm的石灰石进行了静态煅烧和流态化煅烧实验,比较了其产物活性度的差别,探索流态化煅烧制备高活性度石灰的可行性。实验结果表明:流态化煅烧过程中煅烧时间、煅烧温度对产物活性都有影响。随着温度的升高,得到最佳产物活性的煅烧时间会缩短,在此时间之后,继续煅烧产物活性会下降;相比静态煅烧,流态化煅烧不仅提高了石灰石分解的速率,也提高了产物烧结的速率,大幅度缩短了煅烧时间,同时能够在短时间内得到高活性的石灰。在本实验中,石灰石在1 050℃下流化煅烧3 min,得到的产物活性度为338 mL;流态化煅烧过程中,煅烧温度越高,产物活性度对煅烧时间的变化越敏感。

In order to recycle the abandoned limestone resources efficiently, the static-and-fluidized-calcination experiments on the limestone, of which the particle size was at 0.5-1 mm,were conducted.Activities of their products were compared, and the feasibility of preparing the lime with high activity through fluidized calcination was explored.Experimental results showed that the calcination time and temperature both made influence on the product activity in the process of the fiuidized calcination.With the temperature increased, the time to obtain the product of the best activity would be shortened, later ,with the continuous calcination ,the product＇s activity would fall.Compared with static calcination, fiuidized calcination could not only enhance the decomposition rate of the limestone,but also increased the sintering rate of the product.Meanwhile, fluidized calcination could significantly shorten the calcination time and could get the lime with high activity in a short time. In these experiments,it was found that the activity of the product was 338 mL,with the fluidized calcination of the limestone for 3 min at 1 050 ~C.During the fluidized calcination experiment, with the higher calcination temperature, the activity of the product was more sensitive to the change of the calcination time.