Ziejewska Celina, Bąk Agnieszka, Hodor Krzysztof, Hebda Marek
Faculty of Materials Engineering and Physics, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland.
NETZSCH (Netzsch Instrumenty Sp. z o.o.), Halicka 9, 31-036 Cracow, Poland.
Materials (Basel). 2023 Sep 3;16(17):6054. doi: 10.3390/ma16176054.
Massive amounts of deposited coal gangue derived from the mining industry constitute a crucial problem that must be solved. On the other hand, common knowledge about the recycling of glass products and the reuse of waste glass is still insufficient, which in turn causes economic and environmental problems. Therefore, this work investigated lightweight geopolymer foams manufactured based on coal gangue, metakaolin, and a mix of them to evaluate the influence of such waste on the geopolymer matrix. In addition, the effect of 20% (wt.) of waste glass on the foams was determined. Mineralogical and chemical composition, thermal behaviour, thermal conductivity, compressive strength, morphology, and density of foams were investigated. Furthermore, the structure of the geopolymers was examined in detail, including pore and structure thickness, homogeneity, degree of anisotropy, porosity with division for closed and open pores, as well as distribution of additives and pores using micro-computed tomography (microCT). The results show that the incorporation of waste glass increased compressive strength by approximately 54% and 9% in the case of coal-gangue-based and metakaolin-based samples, respectively. The porosity of samples ranged from 67.3% to 58.7%, in which closed pores constituted 0.3-1.8%. Samples had homogeneous distributions of pores and additions. Furthermore, the thermal conductivity ranged from 0.080 W/(m·K) to 0.117 W/(m·K), whereas the degree of anisotropy was 0.126-0.187, indicating that the structure of foams was approximate to isotropic.
采矿业产生的大量废弃煤矸石是一个必须解决的关键问题。另一方面，关于玻璃产品回收利用和废玻璃再利用的常识仍然不足，这反过来又引发了经济和环境问题。因此，本研究调查了基于煤矸石、偏高岭土及其混合物制备的轻质地质聚合物泡沫，以评估此类废弃物对地质聚合物基体的影响。此外，还测定了20%（重量）废玻璃对泡沫的影响。研究了泡沫的矿物学和化学组成、热行为、热导率、抗压强度、形态和密度。此外，还详细研究了地质聚合物的结构，包括孔隙和结构厚度、均匀性、各向异性程度、闭孔和开孔划分的孔隙率，以及使用微型计算机断层扫描（microCT）对添加剂和孔隙的分布情况。结果表明，添加废玻璃后，基于煤矸石的样品和基于偏高岭土的样品的抗压强度分别提高了约54%和9%。样品的孔隙率在67.3%至58.7%之间，其中闭孔占0.3 - 1.8%。样品的孔隙和添加剂分布均匀。此外，热导率在0.080W/（m·K）至0.117W/（m·K）之间，各向异性程度为0.126 - 0.187，表明泡沫结构近似各向同性。
