淤泥和电石渣基新型轻质陶砖的制备

Preparation of New Lightweight Ceramic BricksBased on Silt and Carbide Slag

为了实现淤泥和电石渣的高效资源化利用,采用淤泥和电石渣为主要原料,以抗压强度为主要指标探明制备轻质陶砖的最优工艺。通过单因素实验探讨了原料配比、焙烧温度、保温时间对轻质陶砖抗压强度的影响,并得出了最佳实验条件。利用X射线衍射仪(XRD)、傅里叶变换红外光谱(FTIR)和扫描电子显微镜(SEM)等分析手段,研究了制备轻质陶砖的反应过程及反应机理。结果表明:当淤泥含量为90%(质量分数)、电石渣含量为10%(质量分数)、焙烧温度为1 100℃、保温时间为40 min、升温速度为4℃/min时,制备的轻质陶砖性能最优,抗压强度可达25.94 MPa,同时兼顾轻质陶砖的低密度特性;埃洛石在升温过程中转化成石英,石英在高温条件下可以促进原料变成液相,这是产品得以致密化的原因。本研究为两种大宗固废的综合利用提供了新的思路,有利于减少固废堆存对环境的危害以及传统陶砖制备过程中对自然资源的依赖。

In order to realize the efficient resource utilization of silt and carbide slag,the optimal process for preparing lightweight ceramic bricks was explored by using silt and carbide slag as the main raw materials and compressive strength as the main index.The effects of raw material mix ratio,calcination temperature and holding time on the compressive strength of lightweight ceramic bricks were discussed by single factor experiment,and the optimum experimental conditions were obtained.The reaction process and mechanism of preparing lightweight ceramic bricks were studied by means of X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR)and scanning electron microscopy(SEM).The results show that when the content of silt is 90%(mass fraction),the content of carbide slag is 10%(mass fraction),the calcination temperature is 1100℃,the holding time is 40 min,and the heating rate is 4℃/min,the prepared lightweight ceramic bricks have the best performance.The compressive strength can reach 25.94 MPa,while taking into account the low density characteristics of lightweight ceramic bricks.Halloysite is converted into quartz during the heating process.Quartz can promote the raw material to become liquid phase under high temperature conditions,which is the reason why the product is densified.This study provides a new idea for the comprehensive utilization of two kinds of bulk solid waste,which is beneficial to reduce the harm of solid waste storage to the environment and the dependence on natural resources in the preparation process of traditional ceramic bricks.