高强石膏的制备工艺研究

以天然石膏为原料采用加压水热法制备高强石膏，考察了水热温度、水热时间、膏水质量比和干燥温度对高强石膏力学性能的影响. 利用X射线衍射对不同条件下制备得到的高强石膏进行物相和结晶度分析，得出了天然石膏制备高强石膏最佳工艺. 结果表明:在水热温度为120℃~150℃时，高强石膏抗压强度随着水热温度的升高而减小；在水热温度120℃条件下，膏水质量比的增加使高强石膏抗压强度呈先增加后减小的变化趋势；水热时间、干燥温度对高强石膏的抗压强度影响较小；水热温度120℃、水热时间1h、膏水质量比50%、干燥温度110℃的条件下制备出的高强石膏抗压强度达到42.41MPa，符合高强石膏JC/T 2038-2010 强度标准.

Preparation Technology of High Strength Gypsum

High strength gypsum was prepared by pressurized-hydrothermal method，using nature gypsum as raw materials. Effects of hydrothermal temperature and time， the mass ratio between gypsum and water， and drying temperature on mechanical properties of high strength gypsum were investigated. The phase and crystallinity of high strength gypsum prepared under different conditions were characterized by X-ray diffraction.The optimum technology of preparaing high strength gypsum was obtained by nature gypsum. The results show that， the compressive strength of high strength gypsum decreases with the hydrothermal temperature rising from 120℃ to 150℃，the compressive strength of high strength gypsum increases first and then decreases with the mass ratio of gypsum/water increasing when hydrothermal temperature keeps at 120 ℃，However，the hydrothermal time and drying temperature have little effect on the compressive strength of high strength gypsum. The compressive strength of high strength gypsum can reach 42.41MPa at hydrothermal temperature of 120 ℃， hydrothermal time of 1 h，mass ratio of gypsum/water of 1∶1， and drying temperature of 110 ℃，conforming to the standard JC/T 2038-2010.