新疆菱镁矿基本性能及合成MgO-CaO-Fe_(2)O_(3)砂  

Basic Properties of Magnesite from Xinjiang and Synthesis of MgO-CaO-Fe_(2)O_(3) Sand

作　　者：王嘉玮 刘百宽 高云琴[1] 田晓利 Wang Jiawei;Liu Baikuan;Gao Yunqin;Tian Xiaoli(National Experimental Teaching Demonstration Center for Inorganic Nonmetallic Materials,College of Materials Science and Engineering,Xi’an University of Architecture&Technology,Xi’an,Shaanxi 710055;Puyang Refractories Group Co.,Ltd.,Puyang,He’nan 457100)

机构地区：[1]西安建筑科技大学材料科学与工程学院,无机非金属材料国家级实验教学示范中心,陕西西安710055 [2]濮阳濮耐高温材料(集团)股份有限公司,河南濮阳457100

出　　处：《非金属矿》2021年第5期23-26,30,共5页Non-Metallic Mines

基　　金：陕西省工业重点攻关项目(2018ZDXM-GY-128)。

摘　　要：以新疆和静菱镁矿为原料,研究了该菱镁矿的基本性能,添加CaO和Fe_(2)O_(3),采用一步烧结法制备MgO-CaO-Fe_(2)O_(3)合成砂,分析了合成砂的化学、矿物组成及显微结构特征。结果表明,不同外观性状的菱镁矿石中元素Ca、Fe、Al和Si赋存状态不同,但CaO含量均较高(>1.08%),SiO_(2)含量均极低(<0.25%),为高钙低硅菱镁矿。在成型压力100 MPa、焙烧温度1600℃、保温时间为3 h条件下,制备的MgO-CaO-Fe_(2)O_(3)合成砂综合性能最好,合成砂颗粒体积密度为3.42 g/m_(3),吸水率为0.7%,物化指标满足并优于YB/T 101-2018标准要求。合成砂中MgO晶体多为圆形或椭圆形粒状,晶粒尺寸20~60μm,晶体间均匀分布2CaO·Fe_(2)O_(3)结合相,杂质SiO2主要以3CaO·SiO_(2)形式聚集嵌布于结合相中,Al_(2)O_(3)以4CaO·Al_(2)O_(3)·Fe_(2)O_(3)形式均匀分布于结合相中。Using Hejing magnesite in Xinjiang as raw material,the basic properties of magnesite were studied,and the MgO-CaO-Fe_(2)O_(3)synthetic sand was prepared by one-step sintering method through adding CaO and Fe_(2)O_(3).Chemical,mineral composition and microstructure characteristics of the synthetic sand were analyzed.Results indicate that in magnesites with different appearance properties,the occurrences of element Ca,Fe,Al,Si are different.The common features of those magnesites are high content of CaO(>1.08%)and extremely low content of SiO_(2)(<0.25%),and they belong to magnesite with high calcium and low silicon.MgO-CaO-Fe_(2)O_(3)synthetic sand prepared under the condition of forming pressure of 100 MPa,roasting temperature of 1600℃and holding time of 3 h has the best comprehensive properties,the particle bulk density of which is 3.42 g/cm3 and water absorption is 0.7%.The physical and chemical indexes of the synthetic sand meet and exceed the requirements of YB/T 101-2018 standard.Most of the MgO crystals in the synthetic sand are round or elliptical granules and the crystalline sizes are 20-60μm.The 2CaO·Fe_(2)O_(3)bonding phase is uniformly distributed among the MgO crystals.The SiO_(2)impurity is aggregated and embedded in the bonding phase mainly in the form of 3CaO·SiO_(2),while Al_(2)O_(3)is uniformly distributed in the bonding phase in the form of 4CaO·Al_(2)O_(3)·Fe_(2)O_(3).

关 键 词：菱镁矿 高钙低硅 MgO-CaO-Fe_(2)O_(3)合成砂 一步烧结法 

分 类 号：TQ175.73[化学工程—硅酸盐工业]