粉煤灰、矿粉和水泥对脱硫建筑石膏性能影响

Effect of fly ash,blast furnace slag and cement on characteristics of FGD building gypsum

通过试验研究了粉煤灰、矿粉和水泥掺量及掺加种类对脱硫建筑石膏性能影响。结果表明:(1)单掺粉煤灰、双掺粉煤灰和矿粉(或水泥)和三掺粉煤灰、矿粉和水泥具有缓凝作用,粉煤灰和矿粉的掺入降低了标准稠度用水量,水泥的掺入提高了标准稠度用水量。(2)单掺粉煤灰且随着粉煤灰掺量增加,试样强度和耐水性在降低,其掺量不宜大于10%;双掺粉煤灰和矿粉且随着矿粉掺量增加,试样强度显著降低,而耐水性先降低后增加;双掺粉煤灰和水泥且随着水泥掺量增加,试样强度在降低,而耐水性先提高后降低,水泥掺量不宜大于7.5%。(3)在总掺量相同时,通过粉煤灰、矿粉和水泥掺量的优化组合,双掺粉煤灰和水泥与三掺粉煤灰、矿粉和水泥试样强度和软化系数高于单掺粉煤灰、双掺粉煤灰和矿粉试样。

The influences of admixture replacement and admixture types of fly ash, blast furnace slag and cement on characteristics of FGD building gypsum were studied . The results showed that （1） Adding fly ash , adding fly ash and blast furnace slag（or cement） and adding fly ash, blast furnace slag and cement prolonged the setting time, adding fly ash and blast furnace slag reduced the water requirement of normal consistency , on the contrary, adding cement increased the water requirement of normal consistency. （2） When the fly ash was added separately, strength and water resistance of the samples decreased with the increase of fly ash content, the admixture replacement of fly ash should not be greater than 10%; when fly ash and blast furnace slag were added compositely, the strength of the samples decrease significantly and its water resistance decreased firstly and then increase, with the increase of blast furnace slag dosage; When fly ash and cement were added compositely, the strength of the samples decrease and its water resistance increase firstly and then decrease, with the increase of cement dosage, the admixture replacement of cement should not be greater than 7.5%. （3） As total amounts of admixtures were equivalent, the strength and water resistance of adding cement and fly ash and adding fly ash, blast furnace slag and cement specimens were higher than that of adding fly ash and adding fly ash and blast furnace slag specimens, by adjusting the content of fly ash, blast furnace slag and cement.