矸石电厂粉煤灰的化学激发及活化机理研究

Study on the Chemical Activation and Mechanism Fly Ash from Coal Gangue-combustion Power Plant

以矸石电厂粉煤灰为研究对象,采用工业石灰、石膏、硫酸钠激活其火山灰活性,研究了激活剂掺量对矸石电厂粉煤灰活性的影响。通过正交实验研究了复合活化粉煤灰以及陈腐工艺对水泥胶砂试样不同龄期抗压强度影响规律,并通过扫描电镜(SEM)对胶砂试样28 d龄期的微观结构进行了表征,揭示了活化机理。结果表明,化学活化能有效激发矸石电厂粉煤灰的早期活性,成本低廉,工艺简单。活化剂作用于矸石电厂粉煤灰,存在最佳掺量,正交实验得到活化剂复配比为:氧化钙5%,石膏1%,硫酸钠4%。陈腐工艺有利于粉煤灰的化学活化,对胶砂试样28d抗压强度有一定程度提高。

The pozzolanicity of gangue-combustion fly ash is activated using lime, gypsum and sodium sulfate. The influence of activator dosage to fly ash activity is studied. Through orthogonal experiment, the influence rule of complex activation fly ash and mustiness craft to compression strength of cement mortar samples in different ages is studied. The microstructure of 28 d cement mortar samples is characterized by scanning electron microscopy （SEM）, and further the activation mechanism is revealed. The results show that, chemical activation can activate early activity of fly ash efficiently, the cost is low, and the craft is simple. The activators exist the optimum proportion acting on the fly ash, which can be gained from orthogonal experimenti lime 5%, gypsum 1%, sodium sulfate 4%. Mustiness craft is good for chemical activation on fly ash, it can promote the 28 d compressive strength.