煅烧法与常压酸化法制备磷Ⅱ型无水石膏的水化性能研究  

Study on hydration properties of typeⅡanhydrite prepared by calcination and atmospheric acidification

作　　者：张桂东 杨雪娇 郭旭东 杨林[1,2] ZHANG Guidong;YANG Xuejiao;GUO Xudong;YANG Lin(School of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China;Guizhou Engineering Research Center for High Efficiency Utilization of Industrial Waste,Guiyang 550025,China;Yunnan Yuntianhua Environmental Protection and Technology Co.,Ltd.,Kunming 650300,China)

机构地区：[1]贵州大学化学与化工学院,贵州贵阳550025 [2]贵州省工业废弃物高效利用工程研究中心,贵州贵阳550025 [3]云南云天化环保科技有限公司,云南昆明650300

出　　处：《无机盐工业》2024年第2期104-110,共7页Inorganic Chemicals Industry

基　　金：国家重点研发计划项目(2018YFC1900206-2);贵州省科技计划项目(黔科合平台人才[2019]5409号);校企合作项目(YTH4420-WB-FW-2022-001009-00)。

摘　　要：以磷石膏为原料,分别采用煅烧法和常压酸化法制备磷Ⅱ型无水石膏,通过物相组成、微观形貌、化学组成及粒径分布,分析比较了两种方法制备的磷Ⅱ型无水石膏的差异性。在激发剂明矾不同掺量下,分析比较不同制备方法对磷Ⅱ型无水石膏的凝结时间、硬化体强度及水化率的影响。结果表明:由煅烧法制得的磷Ⅱ型无水石膏AH-1的微观形貌呈菱形,由常压酸化法制得的磷Ⅱ型无水石膏AH-2的微观形貌呈矩形,其中AH-2结晶度及纯度高、平均粒径小、比表面积大;当未掺明矾时,无水石膏水化硬化缓慢,终凝时间在35 h以上,28 d水化率在30%左右;当明矾质量分数为1%时,AH-1的终凝时间由40 h 20 min缩短至5 h 40 min,AH-2的终凝时间由35h20min缩短至4h20min,28d抗压强度分别为空白组的2.54倍和3.01倍;随着明矾掺量的增加,AH-1和AH-2的性能差异逐渐减小,AH-1和AH-2的终凝时间相差在30 min以内,28 d抗压强度均为空白组的3.2倍。同时,AH-2水化生成的二水石膏表面光滑,搭接更加致密。通过比较可知,常压酸化法制备磷Ⅱ型无水石膏工艺更具优势。TypeⅡanhydrite was prepared by calcination method and atmospheric acidification method using phosphogypsum as raw material.The differences of typeⅡanhydrite prepared by the two methods were analyzed and compared through the analysis of phase composition,micro-morphology,chemical composition and particle size distribution.The effects of different preparation methods on the setting time,hardening strength and hydration rate of typeⅡanhydrite were analyzed and compared under different dosage of alum.The results showed that the microstructure of typeⅡanhydrite AH-1 prepared by calcination was diamond shaped,and that of typeⅡanhydrite AH-2 prepared by atmospheric acidification was rectangular,in which AH-2 had high crystallinity and purity,small average particle size and large specific surface area.When the anhydrite was not mixed with alum,the hydration hardening was slow,the final coagulation time was more than 35 h,and the hydration rate was about 30%in 28 d.When the alum content was 1%(mass fraction),the final coagulation time of AH-1 was shortened from 40 h 20 min to 5 h 40 min,the final coagulation time of AH-2 was shortened from 35 h 20 min to 4 h 20 min,and the compressive strength of 28 d was 2.54 times and 3.01 times of that of the blank group,respectively.With the increase of alum content,the performance difference between AH-1 and AH-2 was gradually decreased.The final coagulation time difference between AH-1 and AH-2 was less than 30 min,and the 28 d compressive strength was 3.2 times that of the blank group.At the same time,the surface of the dihydrate gypsum produced by AH-2 hydration was smooth and the bonding was more dense.By comparison,it could be seen that the preparation process of typeⅡanhydrite by atmospheric pressure acidification was more advantageous.

关 键 词：磷石膏 磷Ⅱ型无水石膏 活性激发 水化硬化 

分 类 号：TQ177.3[化学工程—硅酸盐工业]