Przybek Agnieszka, Romańska Paulina, Korniejenko Kinga, Krajniak Krzysztof, Hebdowska-Krupa Maria, Łach Michał
CUT Doctoral School, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland.
Faculty of Material Engineering and Physics, Cracow University of Technology, Jana Pawła II 37, 31-864 Cracow, Poland.
Materials (Basel). 2025 Jul 3;18(13):3150. doi: 10.3390/ma18133150.
Despite the availability of various materials for chimney applications, ongoing research seeks alternatives with improved thermal and chemical resistance. Geopolymers are a promising solution, exhibiting exceptional resistance to high temperatures, fire, and aggressive chemicals. This study investigates fly ash-based lightweight geopolymer concretes that incorporate expanded clay aggregate (E.C.A.), perlite (P), and foamed geopolymer aggregate (F.G.A.). The composites were designed to ensure a density below 1200 kg/m, reducing overall weight while maintaining necessary performance. Aggregate content ranged from 60 to 75 wt.%. Physical (density, thickness, water absorption), mechanical (flexural and compressive strength), and thermal (conductivity, resistance) properties were evaluated. F.G.A. 60 achieved a 76.8% reduction in thermal conductivity (0.1708 vs. 0.7366 W/(m·K)) and a 140.4% increase in thermal resistance (0.1642 vs. 0.0683). The F.G.A./E.C.A./P 60 mixture showed the highest compressive strength (18.069 MPa), reaching 52.7% of the reference concrete's strength, with a 32.3% lower density (1173.3 vs. 1735.0 kg/m). Water absorption ranged from 4.9% (REF.) to 7.3% (F.G.A. 60). All samples, except F.G.A. 70 and F.G.A. 75, endured heating up to 800 °C. The F.G.A./E.C.A./P 60 composite demonstrated well-balanced performance: low thermal conductivity (0.2052 W/(m·K)), thermal resistance up to 1000 °C, flexural strength of 4.386 MPa, and compressive strength of 18.069 MPa. The results confirm that well-designed geopolymer lightweight concretes are suitable for chimney and flue pipe linings operating between 500 and 1000 °C and exposed to acidic condensates and aggressive chemicals. This study marks the initial phase of a broader project on geopolymer-based prefabricated chimney systems.
尽管有各种材料可用于烟囱应用，但正在进行的研究仍在寻找具有更高耐热性和耐化学性的替代材料。地质聚合物是一种很有前景的解决方案，对高温、火灾和腐蚀性化学物质具有出色的抗性。本研究调查了掺入膨胀粘土骨料（E.C.A.）、珍珠岩（P）和泡沫地质聚合物骨料（F.G.A.）的粉煤灰基轻质地质聚合物混凝土。这些复合材料的设计目的是确保密度低于1200 kg/m³，在保持必要性能的同时减轻整体重量。骨料含量范围为60至75 wt.%。对其物理性能（密度、厚度、吸水率）、力学性能（抗弯强度和抗压强度）和热性能（导热系数、热阻）进行了评估。F.G.A. 60的导热系数降低了76.8%（从0.7366 W/(m·K)降至0.1708 W/(m·K)），热阻增加了140.4%（从0.0683增至0.1642）。F.G.A./E.C.A./P 60混合物的抗压强度最高（18.069 MPa），达到参考混凝土强度的52.7%，密度低32.3%（1173.3 vs. 1735.0 kg/m³）。吸水率范围为4.9%（参考样）至7.3%（F.G.A. 60）。除F.G.A. 70和F.G.A. 75外，所有样品都能承受高达800°C的加热。F.G.A./E.C.A./P 60复合材料表现出性能平衡：导热系数低（0.2052 W/(m·K)），1000°C以下的热阻，抗弯强度为4.386 MPa，抗压强度为18.069 MPa。结果证实，精心设计的地质聚合物轻质混凝土适用于在500至1000°C之间运行并暴露于酸性冷凝物和腐蚀性化学物质的烟囱和烟道内衬。本研究标志着基于地质聚合物的预制烟囱系统更广泛项目的初始阶段。
