脱硫灰用作硅酸盐水泥缓凝剂的试验研究

Experimental study of desulphurization residues as retarder of Portland cement

研究了以不同来源脱硫灰对两种水泥熟料的凝结时间、安定性、抗压强度和抗硫酸盐侵蚀性的影响。结果表明,以SO3计0.5%-3.5%的脱硫灰添加量对水泥具有缓凝作用,且效果强于天然石膏,水泥安定性合格,抗压强度、抗硫酸盐侵蚀能力与掺天然石膏的相当。当熟料中C3A和C4AF总量一定、C3A/C4AF较低时,与天然石膏配方相比,脱硫灰配方的缓凝时间较长、早期强度较高。对于烧结机脱硫灰,其碱和氯含量较高,会一定程度减弱其缓凝效果。

The effects of desulphurization residues from different sources on setting time, soundness, compressive strength and sulphate resistance capability of two kinds of cement were studied. The result showed that the desulphurization residues had retarded setting action for cement when its addition amount was 0.5% -3.5%（meter by SO3）, and more effective than natural gypsum. The soundness of cement could meet demand, the compressive strength and sulphate resistance capability of cement were equivalent to the cement that using natural gypsum as retarder. Compared with the cement that adding natural gypsum, the setting time of cement that adding desulphurization residues would be prolonged and the early-age strength of cement that adding desulphurization residues would be increased when the same total amount of C3 A and C4 AF was certain and C3A/C4 AF was low. The retarding effect of the sintering machine desulphurization residues would be weakened due to the high chlor-alkali content.