磷尾矿与粉煤灰制备高强陶粒试验研究

Research on Preparation of High Strength Ceramsite by Using Phosphorus Tailings and Fly Ash

以磷尾矿、粉煤灰为主要原料,石英尾矿为校正组分,制备出900级高强陶粒,为磷尾矿综合利用提供了新的途径。在掺量试验基础上,采用正交试验考察了预热温度、预热时间、煅烧温度与烧结时间对陶粒性能的影响,据此进行了煅烧温度与时间单因素试验,并对产物进行X射线衍射(XRD)、扫描电镜(SEM)分析。结果表明,随着磷尾矿掺量的增加,陶粒堆积密度与颗粒强度减小,吸水率上升,当磷尾矿掺量为30%时,颗粒强度为267.0 N,继续增加其掺量,颗粒强度明显降低;煅烧温度对陶粒堆积密度、吸水率与颗粒强度影响最大。在预热温度为400℃,预热时间为20 min,煅烧温度为1200℃,保温时间为30 min,升温速率为10℃/min的条件下,可制得堆积密度为830 kg/m3、吸水率为14.6%、筒压强度为9.8 MPa的900级高强粉煤灰陶粒。

In order to provide a scientific basis for the resource utilization of phosphorus tailings,the phosphorus tailings and fly ash were used as the main raw materials to prepare a high-strength ceramsite with a density of 900.Under the test of phosphorus tailings amount,the orthogonal test was used to investigate the influence of preheating temperature,preheating time,sintering temperature and time on the properties of ceramisite.Based on this,the single factor tests of sintering temperature and time were carried out.Above all,the products were analyzed by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The results showed that with the increase of phosphorus tailings amount,the apparent density and particle strength of ceramsite decreased and the water absorption rate became larger.When the amount of phosphorus tailings was 30%,the particle strength was 267.0 N,and the particle strength decreased significantly as the content of phosphorus tailings continued to increase;the calcination temperature had the greatest influence on the apparent density,water absorption rate and particle strength of ceramsite.When preheating temperature was 400℃,preheating time was 20 min,sintering temperature was 1200℃,sintering time was 30 min,and the heating rate was 10℃/min,the 900-grade high strength light aggregate with bulk density of 830 kg/m3,water absorption rate of 14.6%and cylinder pressure strength of 9.8 MPa could be prepared.