原状铅锌尾矿地聚反应制备免烧砖的试验研究

Experimental Study of Unburned Brick Prepared with Undisturbed Lead-zinc Tailings by Geopolymerization

为优化原状铅锌尾矿制备地聚物免烧砖的配比参数和工艺条件,研究了碱含量、矿粉掺量、成型压力、水料比和初始养护温度等因素对铅锌尾矿地聚物砖的抗压强度、吸水率的影响,并通过SEM、XRD和FTIR对铅锌尾矿地聚物进行了表征。结果表明:原状铅锌尾矿在NaOH作用下具有一定的碱激发活性,可用于制备地聚物砖;铅锌尾矿地聚物砖最佳配比和压制工艺参数为:增强改性最为经济高效的矿粉掺量为20%,碱含量为9%,水料比为15%,成型压力为15MPa,初始养护温度为50℃。矿粉掺量20%改性的铅锌尾矿地聚物砖的抗压强度为34.4MPa,吸水率为5.6%。

In order to optimize the mixture design parameters and process conditions of unburned geopolymer brick prepared with undisturbed lead-zinc tailings,the effects of alkali content,slag powder content,molding pressure,water-material ratio and initial curing temperature on the compressive strength and water absorption rate of lead-zinc tailings geopolymer bricks were studied.Furthermore,the lead-zinc tailings geopolymers were characterized by SEM,XRD and FTIR.The results show that the undisturbed lead-zinc tailings have certain alkali-exciting activity and can be used to prepare unburned geopolymer bricks.The optimum mixture design and pressing process parameters of the lead-zinc tailings geopolymer bricks are:20%slag powder is the most economical and efficient to enhance and modify the geopolymer bricks,the alkali content is 9%,the water-material ratio is 15%,the molding pressure is 15 MPa,and the initial curing temperature is 50℃.The compressive strength of the lead-zinc tailings geopolymer brick modified with 20%slag powder is 34.4 MPa,and the water absorption rate is 5.6%.