A novel energy-efficient kapok filter paper with high DHC for solid-oil mixed aerosol: Performance and loading behavior evolution mechanism

摘要

Although typical high efficiency filter media for gas turbine exhibit short lifespan under harsh conditions with excessive oily aerosol, rare literatures are available concerning fundamental reason or introducing filter media for addressing aforementioned conditions. Herein, we developed a novel kapok filter paper with high energyefficiency and dust holding capacity (DHC) against solid-oil mixed aerosol. Loading behavior of filter media was characterized in terms of both macroscopic loading behavior (pressure drop and DHC evolution over oil content) and micro-scale particle deposition behavior. Owing to hollow lumen and waxy surface of kapok fiber, the novel filter paper was fluffy and oleophilic, which made it outperform typical commercial filter media (F01 and F02) in energy saving and DHC. Under harshest conditions where F01 and F02 manifested low DHC of 8.0 g/m(2), 13.3 g/m(2) and 29.1 g/m(2), 34.7 g/m(2) at the oil content of 50%, 75%, respectively, the kapok filter paper owned notably excellent DHC of 1603 g/m(2), 240.8 g/m(2), respectively. Moreover, it was revealed that loading behavior evolution (resulted from the increase of oil content) was subject to deposition behavior. Once oil content was above 25%, pressure drop profiles transitioned from that of solid particles loading to that of liquid particles loading. Depositions structure varied from well-defined particles to particles-in-oil with films covered. Due to formation of a porous structure, a critical maximum DHC occurred for mixed aerosol with 25% oil content. Finally, a particle deposition mechanism was proposed, for the first time, to explain the loading behavior evolution over oil content.