CN110436946B - 一种用于热风炉拱顶高温部位的耐酸喷涂料 - Google Patents

一种用于热风炉拱顶高温部位的耐酸喷涂料 Download PDF

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CN110436946B
CN110436946B CN201910753892.5A CN201910753892A CN110436946B CN 110436946 B CN110436946 B CN 110436946B CN 201910753892 A CN201910753892 A CN 201910753892A CN 110436946 B CN110436946 B CN 110436946B
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薛海涛
彭云涛
丛培源
侯玮玮
项冰
毛雪松
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Abstract

本发明公开了一种用于热风炉拱顶高温部位的耐酸喷涂料,由骨粉料外加结合剂组成;所述骨粉料:废弃高压电瓷骨料50~58%;废弃高压电瓷细粉12~30%;三级矾土粉3~15%;石英粉6~14%;425#硅酸盐水泥0.3~1%;抗反弹剂0.05~1%;增塑剂0.05~1%;所述结合剂为液态水玻璃,在使用时加入,用量为骨粉料12~18wt%。本发明用于热风炉拱顶高温部位耐酸喷涂料,具有强度高、耐酸性好、高温性能好,易于施工;将结构致密、耐酸性好的废旧高压作为骨料加入热风炉拱顶高温部位耐酸喷涂料中,节约成本,达到固废资源回收利用效果,同时材料性能优良。

Description

一种用于热风炉拱顶高温部位的耐酸喷涂料
技术领域
本发明属于材料技术领域,具体涉及一种用于热风炉拱顶高温部位的耐酸喷涂料。
背景技术
炼铁工序占钢铁工业能耗的主要部分,高风温是实现炼铁高炉节能的重要措施,据研究,在目前我国高炉风温范围内,每提高100℃风温,可降低焦比15~20kg/t铁,可相应提高产量3%左右。此外,高风温还是实行高炉喷吹煤粉的必要条件。随着炼铁技术的不断进步,现代高炉向大型、高效、长寿等方向发展,提高高炉热风炉风温所具有的降低炼铁焦比、提高高炉生铁产量、提高喷煤比和降低高炉生产成本等作用越来越显著。国际上先进企业的热风炉风温在1300℃以上。
随着热风炉高温技术的发展,热风炉炉顶风温不断提高,热风炉拱顶在生产过程中,存在有NOx气体物质,当温度达到1300℃时,产生NOx气体速度增大,当NOx气体在炉壳内表面温度低的地方与水蒸气相遇,会形成严重腐蚀的硝酸盐溶液,对炉壳产生晶间应力腐蚀。一般热风炉拱顶炉壳会先涂一层防晶间应力涂料,再喷涂一层耐高温的耐酸喷涂料作为保护内衬,因此研究一种耐高温的耐酸喷涂料显得尤为重要。
CN201010536567.2炼铁高炉热风炉用耐酸喷涂料组合物及其使用方法,采用酸性或者半酸性材料为主材料,添加一定量增塑剂、结合剂和固化剂形成耐酸喷涂料。但是其加入过多粘土,对材料高温性能不利,材料成分中Al2O3成分控制不严,材料在高温烧结下会变形严重。
CN201410523298.4高强耐腐蚀耐火浇注料,采用废电瓷,废砖、煤矸石等为骨料,加入氧化锆纤维、氧化钇等形成高强耐腐蚀浇注料。但是其氧化锆纤维、氧化钇成本高。侧壁、顶部等部位浇注料不可施工。
CN200910089678.0一种防止热风炉拱顶晶间应力腐蚀的方法,采用SiC、Al2O3、Cr2O3填料,粘结剂等形成高温涂料。但是其材料成本高,涂料施工厚度有限。
发明内容
本发明目的在于提供一种耐酸喷涂料,其具有耐火度高、附着率好、强度高、不开裂、耐酸腐蚀性优良等特性。将其用于热风炉拱顶高温部位能降低热风炉酸性介质对炉壳的腐蚀,提高热风炉密封性,减少热损失,有利于热风炉高效长寿。本发明另外一个发明目的在于通过大量采用高压电瓷废旧材料,回收利用固废资源,起到绿色环保作用。
为达到上述目的采用技术方案如下:
一种用于热风炉拱顶高温部位的耐酸喷涂料,由骨粉料外加结合剂组成;
所述骨粉料的组成按质量百分数计如下:
Figure BDA0002168125660000021
所述结合剂为液态水玻璃,在使用时加入,用量为骨粉料12~18wt%。
按上述方案,所述废弃高压电瓷骨料由3-5mm的颗粒、1-3mm的颗粒和0.088-1mm的颗粒混合组成;其中Al2O3含量为38-42wt%,SiO2含量为40-46wt%,Fe2O3含量小于1wt%,Na2O含量小于0.5wt%。
按上述方案,所述废弃高压电瓷细粉,Al2O3含量为38-42wt%,,SiO2含量为40-46wt%,Fe2O3含量小于1wt%,Na2O含量小于0.5wt%,粒度不大于180目。
按上述方案,所述三级矾土粉,Al2O3含量为60-65wt%,,Fe2O3含量小于2wt%,Na2O+K2O含量小于0.6wt%,CaO+MgO含量小于0.6wt%,粒度不大于180目。
按上述方案,所述的石英粉SiO2含量大于99wt%,含水量小于0.1wt%,粒度不大于200目。石英粉不仅耐酸性好,在高温下能还能起到膨胀剂的作用。
按上述方案,所述抗反弹剂为丙烯酸-酰胺共聚物,白色粉体,(20%,20℃)pH值6.5-8.5。为武汉善达化工公司生产,它是独特高分子抗反弹剂,能大幅度降低喷涂料回弹率。
按上述方案,所述的增塑剂为高分子外加剂,白色粉体,(20%,20℃)pH值6.5-8.5。为武汉善达化工公司生产,它具有优良锁水性能、增稠性能,能提高喷涂料粘结能力。
按上述方案,所述水玻璃是在水玻璃溶液中掺加糖醇和多羟醚化三聚氰胺改性而来,密度为1.26-1.35g/cm3
根据权利要求所述的一种用于热风炉顶部高温部位耐酸喷涂料,其特征在于:所述的喷涂料在现场混合并进行喷涂,先将喷涂料主材料按重量比进行搅拌、混合均匀,再加入所述比例的结合剂液体改性水玻璃,采用半干法喷涂设备直接对热风炉顶部部位进行喷涂。
高压电瓷在生产或使用过程中会产生大量的陶瓷废料,高压电瓷废料多半以堆积存放或填埋的形式回收,造成资源浪费和环境污染。这些高压电瓷废料结构致密、硬度高、耐酸碱,化学性能稳定,铝含量从20%到60%不等。其中Al2O3含量在38%以上的具有较高的耐火特性,使其成为一种制作耐高温耐酸喷涂料的优良原料,同时解决了资源浪费和环境污染问题。
本发明相对于现有技术的有益效果如下:
本发明用于热风炉拱顶高温部位耐酸喷涂料,具有强度高、耐酸性好、高温性能好,易于施工;
将结构致密、耐酸性好的废旧高压作为骨料加入热风炉拱顶高温部位耐酸喷涂料中,节约成本,达到固废资源回收利用效果,同时材料性能优良。
采用高效外加剂,在喷涂料中不加塑性粘土,在保证材料施工性能前提下,大幅度提高材料的高温使用性能,保证了热风炉高风温实施。
具体实施方式
以下实施例进一步阐释本发明的技术方案,但不作为对本发明保护范围的限制。
实施例1
所述喷涂料骨粉料由如下原料组份及重量百分数组成:
Figure BDA0002168125660000031
本实施例所得耐酸喷涂料的理化指标如表1所示。
表1
Figure BDA0002168125660000032
Figure BDA0002168125660000041
实施例2
所述喷涂料骨粉料由如下原料组份及重量百分数组成:
Figure BDA0002168125660000042
本实施例所得耐酸喷涂料的理化指标如表2所示。
表2
Figure BDA0002168125660000043
Figure BDA0002168125660000051
实施例3
所述喷涂料骨粉料由如下原料组份及重量百分数组成:
Figure BDA0002168125660000052
本实施例所得耐酸喷涂料的理化指标如表3所示。
表3
Figure BDA0002168125660000053

Claims (4)

1.一种用于热风炉拱顶高温部位的耐酸喷涂料,其特征在于由骨粉料外加结合剂组成;
所述骨粉料的组成按质量百分数计如下:
废弃高压电瓷骨料 50~58%;
废弃高压电瓷细粉 12~30%;
三级矾土粉 3~15%;
石英粉 6~14%;
425#硅酸盐水泥 0.3~1%;
抗反弹剂 0.05~1%;
增塑剂 0.05~1%;
所述结合剂为液态水玻璃,在使用时加入,用量为骨粉料12~18wt%;
所述废弃高压电瓷骨料由3-5mm的颗粒、1-3mm的颗粒和0.088-1mm的颗粒混合组成;其中Al2O3含量为38-42wt%,SiO2含量为40-46wt%,Fe2O3含量小于1wt%, Na2O含量小于0.5wt%;
所述废弃高压电瓷细粉,Al2O3含量为38-42wt%,SiO2含量为40-46wt%,Fe2O3含量小于1wt%, Na2O含量小于0.5wt%,粒度不大于180目;
所述抗反弹剂为丙烯酸-酰胺共聚物,白色粉体,pH值6.5-8.5,所述抗反弹剂为高效反弹剂Staben2013;
所述的增塑剂为高分子外加剂,白色粉体,pH值6.5-8.5,所述增塑剂为高效塑性粘结剂PT10。
2.如权利要求1所述用于热风炉拱顶高温部位的耐酸喷涂料,其特征在于所述三级矾土粉,Al2O3含量为60-65wt%,Fe2O3含量小于2wt%, Na2O+K2O含量小于0.6wt%,CaO+MgO含量小于0.6wt%,粒度不大于180目。
3.如权利要求1所述用于热风炉拱顶高温部位的耐酸喷涂料,其特征在于所述的石英粉SiO2含量大于99wt%,含水量小于0.1wt%,粒度不大于200目。
4.如权利要求1所述用于热风炉拱顶高温部位的耐酸喷涂料,其特征在于所述水玻璃是在水玻璃溶液中掺加糖醇和多羟醚化三聚氰胺改性而来,密度为1.26-1.35g/cm3
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