The Effects of Reaction Conditions on Growth Process of FGD Gypsum Whisker

Abstract

Taking FGD gypsum as raw materials, gypsum whisker was prepared by using hydrothermal method. The effects of reaction temperature, reaction time, desulfurization gypsum slurry concentration and pH value on the growth of gypsum whisker were deeply researched. The optimum conditions for the preparation were that the reaction temperature was 140 ℃ ~ 145 ℃, reaction time was 200 ~ 240min, the slurry concentration was 13% ~ 15% and the slurry pH value was between 4.5 and 5. In this paper, an aspect ratio model formula of calcium sulfate whisker can be expressed as Average aspect ratio = 15.89x - 0.13y + 14.74z - 63.26m - 0.06x2 - 0.14z2 - 0.81m2 - 0.08xz + 0.38xm - 0.01yz + 0.01ym + 0.67zm - 1043.89, the sign x denotes reaction temperature,℃; y denotes reaction time, min; z denotes slurry concentration, %; m denotes pH value of the slurry.