纤维掺量对钢渣薄板碳化固结特性的影响研究

钢铁行业CO2排放量大,钢渣等冶金固废资源化利用困难。钢渣碳化材料安定性和耐久性良好,但抗拉强度低、易开裂,限制了其在建筑领域的应用。本文采用钢渣为碳化原料、聚丙烯纤维为增强材料、碳化养护为手段开发制备纤维增强钢渣碳化材料。以钢渣碳化材料抗压强度、抗折强度和碳酸化程度为判断依据,结合热重、压汞法等微观分析方法,研究聚丙烯纤维掺量对钢渣碳化材料力学性能、碳化固结性能的影响规律。研究发现聚丙烯纤维的加入会降低钢渣碳化材料的抗压强度,但适量的纤维掺入对于提高钢渣碳化材料抗折强度是有利的,随着纤维掺量的增加,钢渣碳化材料抗折强度呈现出先不变,后增加,再减小的变化趋势,在纤维掺量为7 kg/m3时达到最大值。此外,聚丙烯纤维的加入会促进钢渣的水化反应,降低钢渣的碳化反应,提高钢渣碳化材料的密度,降低钢渣碳化材料的孔隙率,但会提高碳化反应生成的碳酸钙的热稳定性。本文的研究结果对其它高钙镁含量材料制备碳化纤维薄板提供参考。

Study on the influence of fiber content on the carbonation consolidation characteristics of steel slag sheet

The CO2 emission of iron and steel industry is large, and the utilization of metallurgical solid waste such as steel slag is difficult. Steel slag carbonation material has good stability and durability, but its low tensile strength and easy cracking limit its application in the construction field. In this paper, steel slag is used as carbonization raw material, polypropylene fiber is used as reinforcement material, and carbonization curing is used to develop and prepare fiber reinforced steel slag carbonization material. Based on the compressive strength, flexural strength and carbonation degree of steel slag carbonation materials, the influence of polypropylene fiber content on the mechanical properties and carbonation consolidation properties of steel slag carbonation materials was studied by means of micro-analysis methods such as thermogravimetry and mercury intrusion method. It is found that the addition of polypropylene fiber will reduce the compressive strength of steel slag carbonation material, but the appropriate amount of fiber is beneficial to improve the flexural strength of steel slag carbonation material. With the increase of fiber content, the flexural strength of steel slag carbonation material shows a trend of first unchanged, then increased, and then decreased, reaching the maximum when the fiber content is 7 kg/m3. In addition, the addition of polypropylene fiber will promote the hydration reaction of steel slag, reduce the carbonation reaction of steel slag, increase the density of steel slag carbonation material, reduce the porosity of steel slag carbonation material, but will improve the thermal stability of calcium carbonate produced by carbonation reaction. The results of this paper provide a reference for the preparation of carbonized fiber sheet by other high calcium and magnesium content materials.