Department of Mechanical Engineering and Aeronautics, University of Patras, 26500, Patras, Greece.
Department of Environmental Engineering, Democritus University of Thrace, 67100, Xanthi, Greece.
Bioprocess Biosyst Eng. 2023 May;46(5):747-759. doi: 10.1007/s00449-023-02862-9. Epub 2023 Mar 22.
In this study, experimental tests and numerical simulations (Abaqus) were performed to examine the durability of four impeller materials [steel, polyethylene, polypropylene and glass fiber reinforced polymer (GFRP)] in an anaerobic digester environment. Specimens of these materials were prepared and immersed in a bath containing anaerobic digester liquor while operated at 40 °C for a period of 8 months. Periodically (2, 4, 6 and 8 months) sample specimens were removed from the bath and the tensile strength and elastic modulus were determined. As expected, thermoplastic materials and especially GFRP exceeded higher absorption of moisture than steel, although aging effect on steel was more pronounced due to corrosion, as evidenced by SEM imaging. The results demonstrate that polyethylene was not acceptable as construction material for anaerobic digester paddle mixer. On the contrary steel, GFRP and PP remained highly unaffected with a negligible increase of the maximum stress, 1.6%, 0.9% and 3.0%, respectively.
本研究通过实验测试和数值模拟（Abaqus），考察了四种叶轮材料（钢、聚乙烯、聚丙烯和玻璃纤维增强聚合物（GFRP））在厌氧消化环境中的耐久性。制备了这些材料的试件，并将其浸入含有厌氧消化液的浴中，在 40°C 下运行 8 个月。定期（2、4、6 和 8 个月）从浴中取出样品试件，测定拉伸强度和弹性模量。不出所料，热塑性材料，尤其是 GFRP，比钢吸收更多的水分，尽管由于腐蚀，钢的老化效应更为明显，这可以通过 SEM 成像证明。结果表明，聚乙烯不适宜用作厌氧消化搅拌器的结构材料。相反，钢、GFRP 和 PP 几乎没有受到影响，最大应力分别仅增加了 1.6%、0.9%和 3.0%。
