城市生活垃圾焚烧飞灰对水泥水化过程的影响研究

Study on the Influence of Municipal Solid Waste Incineration Fly Ash on Cement Hydration Process

研究了经过化学螯合稳定化处理后的城市生活垃圾焚烧飞灰(CFA)对水泥浆体凝结时间、抗压强度、电阻率和水化产物的影响规律。结果表明,掺入CFA后,水泥浆体的凝结时间缩短,在3 d和28 d龄期时生成了水化产物Friedel盐,且水泥浆体的液相离子浓度增大,电阻率减小;当CFA掺量为5%时,硬化水泥浆体7 d龄期内的抗压强度提高,但28 d抗压强度降低;当CFA掺量从10%增大到60%时,硬化水泥浆体的抗压强度均小于空白组,并逐渐降低。

The effects of municipal solid waste incineration fly ash after chemical chelating agent stabilization treatment(CFA)on the setting time,compressive strength,electrical resistivity and hydration products of cement pastes were studied.The results show that the setting time of cement paste is shortened after CFA is mixed,and Friedel’s salt is formed at the age of 3 days and 28 days.In addition,the electrical resistivity of the cement paste is decreased due to the increase of ion concentration of the liquid phase.When the amount of CFA is 5%,it helps to improve the compressive strength of the hardened cement paste during the 7 days,but the compressive strength at 28 days decreases.When the amount of CFA is increased from 10%to 60%,the compressive strength of the hardened cement paste is smaller than that of the control group and decreases gradually.