磷建筑石膏浆料的流变性能

采用Brookfield RST-SST软固体流变仪研究了集料类型、掺量及混合料颗粒堆积状态对磷建筑石膏浆料流变行为的影响,并采用Herschel-Bulkley流变模型对测试结果进行了拟合.结果表明:浆料流变曲线中存在1个拐点,拐点两侧浆料剪切增稠的程度不同.集料类型对浆料流变参数的影响不明显.磷建筑石膏和集料混合料中颗粒堆积状态对浆料的流变参数影响很大,同时屈服应力较临界剪切速率和流变指数更易受到颗粒堆积状态的影响.当集料掺量(质量分数,下同)为5%~10%时,浆料的流变参数大于磷建筑石膏净浆的流变参数;当集料掺量为10%~40%时,浆料的流变参数小于磷建筑石膏净浆的流变参数.

Rheological Properties of Calcined Gypsum from Phosphogypsum Slurry

The effects of type and amounts of aggregate and cumulate state of particles on rheological properties of calcined gypsum from phosphogypsum slurry were studied by Brookfield soft solid rheometer(RST SST). And the data were fitted by the Herschel Bulkley model. The results show that there is an inflection point in the rheological curve when shear rate increases. The degree of shear thickening of the slurries in two sides of inflection point is different. There is no effect of type of aggregates on the rheological parameters of the slurry. The rheological parameters of the calcined gypsum from phosphogypsum slurry are affected by cumulated state of particles. And yield stress is more susceptible to cumulated state of particles than critical shear rate and rheological index. The rheological parameters of calcined gypsum from phosphogypsum slurries are higher than those of calcined gypsum from phosphogypsum paste when the amount of aggregate is 5%10%(by mass). But the results are opposite when the amount of aggregate is 10%40%.