CN107651968A - 一种精炼钢包用铬质引流砂及其制备方法 - Google Patents

一种精炼钢包用铬质引流砂及其制备方法 Download PDF

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CN107651968A
CN107651968A CN201710843919.0A CN201710843919A CN107651968A CN 107651968 A CN107651968 A CN 107651968A CN 201710843919 A CN201710843919 A CN 201710843919A CN 107651968 A CN107651968 A CN 107651968A
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刘丽
高梅
王团收
任林
张盛
赵伟
车晓梅
刘美荣
曹仁锋
王伟伟
张晓波
赵冉
胡玲军
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Beijing Lier High Temperature Materials Co Ltd
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Abstract

本发明提出了一种精炼钢包用铬质引流砂及其制备方法,用以解决引流砂自动开浇自开率低、生产成本高、环境影响大的问题,一种精炼钢包用铬质引流砂,包括以下质量百分比的原料:1~20%的铬矿砂、40~60%的钛铝酸钙电熔球、30~40%的压裂石英砂和0.6~1%碳添加剂,所述碳添加剂碳为炭黑和石墨的混合物,本发明所引入的钛铝酸钙作为炼钢的工业废渣,将它应用到了引流砂中,得到有效地回收利用,极大地降低了生产制造成本。采用钛铝酸钙电熔球部分代替铬矿砂,减少污染,洁净钢水,可解决原料依赖进口,成本高等问题。

Description

一种精炼钢包用铬质引流砂及其制备方法
技术领域
本发明涉及耐火材料技术领域,特别是指一种精炼钢包用铬质引流砂及其制备方法。
背景技术
为避免钢包水口部位的钢水被冻结,要在钢包水口内填充引流砂。引流砂的作用机理在于:钢水注入钢包的初期,水口上表面的引流砂接触钢水后迅速烧结而阻碍了熔融钢水的渗透,烧结层在下部引流砂的支撑下能够承受钢水的静压力而不破坏;同时引流砂的烧结速度变慢,烧结层保持一定的厚度。而开浇时下部的未烧结的引流砂因自重作用下落,烧结层失去支撑,导致烧结层在钢水的重力作用下破碎,实现开浇。
钛铁合金是生产链条钢等优质钢、电焊条以及电子、军工产品等的重要原料。随着钛铁合金产业的不断发展,随之产生的渣也越来越多。废渣的大量堆积不仅污染环境,而且会造成资源的浪费,随之产生的渣也越来越多。废渣的大量堆积不仅污染环境,而且会造成资源的浪费。在当今大力倡导建设资源节约型、环境友好型社会的大背景下,如何处理好钛铁渣并使之成为一种有用的材料,无疑具有积极的现实意义。钛铝酸钙时在钛铁合金的冶炼过程中产生的副产品,有资料表明,这种副产品的产生量相当大,合金与渣的比例一般都达到1∶1左右。因此如能将钛铝酸钙作为耐火原料使用,不仅带动地方经济,节约耐火材料行业成本还能减少环境污染。
引流砂的自动开浇是引流砂自身性能的重要指标,如果引流砂不能实现自动开浇,则需要采用烧氧方式引流,这不仅损毁滑动水口,还造成部分钢水的二次氧化,影响铸坯质量,而且对操作工人构成安全隐患。钢水不能开浇还会导致中间包液面偏低,甚至连铸生产线被迫中断等现象。为了提高引流砂的自开率,部分厂家采用精选铬矿为主要原料,但是精选铬矿的价格高昂,成本太高,对环境有影响。
发明内容
针对上述现有技术存在的问题,本发明提供了一种精炼钢包用铬质引流砂的制造方法,该方法制造的引流砂可解决原料依赖进口,成本高等问题,而且产品耐火度高、高温烧结性能好、抗钢水和熔渣侵蚀性好、颗粒粒度分布均匀、流动性好、热膨胀率较小自开率高,低铬环保。
本发明的技术方案是这样实现的:一种精炼钢包用铬质引流砂,包括以下质量百分比的原料:
1~20%的铬矿砂、40~60%的钛铝酸钙电熔球、30~40%的压裂石英砂和0.6~1%碳添加剂,所述碳添加剂碳为炭黑和石墨的混合物。
优选的,所述铬矿砂中Cr2O3≥46%、Fe2O3≤28%、Al2O3≤15%、MgO≤9%,颗粒粒径控制范围为0.10~1.5mm。
优选的,所述钛铝酸钙电熔球中Al2O3≥76%、TiO2≤10%、CaO≤9%、MgO≤4%,颗粒粒径控制范围0.2~2.0mm。
优选的,所述压裂石英砂中SiO2不低于98%,其颗粒粒径为0.5~2.0mm。
优选的,所述炭黑中的碳含量≥90%,石墨微粉中的碳含量为85~90%。
本发明又提出一种精炼钢包用铬质引流砂的制备方法,包含以下步骤:
步骤一,按质量百分比称取10~20%的铬矿砂、40~60%的钛铝酸钙电熔球、30~40%的压裂石英砂和0.6~1%碳添加剂,依次加入到搅拌设备中,高速搅拌15~20min,得混合物A;
步骤二,将步骤一的混合物A置于旋转干燥炉中烘烤,烘烤温度110℃~150℃,烘烤时间为0.5~1h,即得铬质引流砂产品。
本发明的优点:
本发明所引入的钛铝酸钙作为炼钢的工业废渣,将它应用到了引流砂中,得到有效地回收利用,极大地降低了生产制造成本。采用钛铝酸钙电熔球部分代替铬矿砂,减少污染,洁净钢水,可解决原料依赖进口,成本高等问题,钛铝酸钙是六铝酸钙、二铝酸钙、钛酸铝、钛酸钙以及金红石相的固溶体,使引流砂具有良好的抗热震性能、导热性能。高温烧结性能好,自开率高。引入的钛铝酸钙为圆球形状,自身流动性好,利于自开。
具体实施方式
下面将对本发明实施例中的技术方案进行清楚、完整地描述,显然,所描述的实施例仅仅是本发明一部分实施例,而不是全部的实施例。基于本发明中的实施例,本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例,都属于本发明保护的范围。
实施例1
一种精炼铬质铬质引流砂的制备方法,包括以下步骤:
步骤一,按质量百分比称取10%的铬矿砂、60%的钛铝酸钙电熔球、30%的压裂石英砂和0.1%炭黑,0.5%石墨,依次加入到搅拌设备中,高速搅拌15分钟,得混合物A。
步骤二,将步骤一的混合物A置于旋转干燥炉中烘烤,烘烤温度110℃℃,烘烤时间为0.5h,过筛,得粒径为0.5mm的铬质引流砂产品。
本实施例所制备的钢包用铬质引流砂,统计炉数为990炉;开浇炉数为979炉;自动开浇率为98.9%。
实施例2
一种精炼铬质铬质引流砂的制备方法,包括以下步骤:
步骤一,按质量百分比称取15%的铬矿砂、50%的钛铝酸钙电熔球、35%的压裂石英砂和0.2%炭黑,0.6%石墨,依次加入到搅拌设备中,高速搅拌18min,得混合物A。
步骤二,将步骤一的混合物A置于旋转干燥炉中烘烤,烘烤温度110℃~150℃,烘烤时间为0.6h,过筛,得粒径为1.5mm的铬质引流砂产品。
本实施例所制备的钢包用铬质引流砂,统计炉数为1050炉;开浇炉数为1041炉;自动开浇率为99.1%。
实施例3
一种精炼铬质铬质引流砂的制备方法,包括以下步骤:
步骤一,按质量百分比称取20%的铬矿砂、40%的钛铝酸钙电熔球、40%的压裂石英砂和0.3%炭黑,0.7%石墨,依次加入到搅拌设备中,高速搅拌20分钟,得混合物A。
步骤二,将步骤一的混合物A置于旋转干燥炉中烘烤,烘烤温度110℃~150℃,烘烤时间为1h,过筛,得粒径为2mm的铬质引流砂产品。
本实施例所制备的钢包用铬质引流砂,统计炉数为976炉;开浇炉数为969炉;自动开浇率为99.2%。
以上所述仅为本发明的较佳实施例而已,并不用以限制本发明,凡在本发明的精神和原则之内,所作的任何修改、等同替换、改进等,均应包含在本发明的保护范围之内。

Claims (6)

1.一种精炼钢包用铬质引流砂,其特征在于,包括以下质量百分比的原料:
1~20%的铬矿砂、40~60%的钛铝酸钙电熔球、30~40%的压裂石英砂和0.6~1%碳添加剂,所述碳添加剂碳为炭黑和石墨的混合物。
2.如权利要求1所述的一种精炼钢包用铬质引流砂,其特征在于:
所述铬矿砂中Cr2O3≥46%、Fe2O3≤28%、Al2O3≤15%、MgO≤9%,颗粒粒径控制范围为0.10~1.5mm。
3.如权利要求1所述的一种精炼钢包用铬质引流砂,其特征在于:
所述钛铝酸钙电熔球中Al2O3≥76%、TiO2≤10%、CaO≤9%、MgO≤4%,颗粒粒径控制范围0.2~2.0mm。
4.如权利要求1所述的一种精炼钢包用铬质引流砂,其特征在于:
所述压裂石英砂中SiO2不低于98%,其颗粒粒径为0.5~2.0mm。
5.如权利要求1所述的一种精炼钢包用铬质引流砂,其特征在于:
所述炭黑中的碳含量≥90%,石墨微粉中的碳含量为85~90%。
6.如权利要求1至5中任一项所述的一种精炼钢包用铬质引流砂的制备方法,其特征在于,包含以下步骤:
步骤一,按质量百分比称取10~20%的铬矿砂、40~60%的钛铝酸钙电熔球、30~40%的压裂石英砂和0.6~1%碳添加剂,依次加入到搅拌设备中,高速搅拌15~20min,得混合物A;
步骤二,将步骤一的混合物A置于旋转干燥炉中烘烤,烘烤温度110℃~150℃,烘烤时间为0.5~1h,即得铬质引流砂产品。
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Cited By (5)

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CN109249013A (zh) * 2018-09-11 2019-01-22 浙江自立高温科技有限公司 一种用于精炼钢包的引流砂填充结构及加砂工艺
CN110496959A (zh) * 2019-09-20 2019-11-26 乌兰察布市西蒙鼎新技术开发有限公司 一种引流砂的制备方法
CN111545738A (zh) * 2020-05-18 2020-08-18 西峡龙成冶金材料有限公司 一种引流砂及其制备方法与应用
CN112479728A (zh) * 2020-12-23 2021-03-12 河南通宇冶材集团有限公司 无铬环保型引流剂用助熔剂、引流剂和制备方法
CN114180948A (zh) * 2021-11-02 2022-03-15 北京首钢股份有限公司 一种长石类新型引流砂及其制备方法

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