The ceramic slurry is prepared using alumina and calcium carbonate powder as matrix materials,polyvinyl alcohol solution as a binder,and acetic acid as a dispersant. Different porous alumina-based ceramics are printed by micro-extrusion 3D printing technology. The effects of hole structure and thickness on the sewage filtration performance and its affecting mechanism of porous alumina-based ceramics are investigated. The results show that the multi-layer cross-hole alumina-based ceramic samples with the hole diameter less than 0.1 mm are successfully fabricated by the micro-extrusion 3D printing method with a stepwise 30° filling angle and varying filling rates. The cross hole distribution can divert sewage flow and increase the effective filtration area,while the thicker multi-layer cross-hole porous alumina-based ceramic provides a longer path for sewage filtration,facilitating the removal of small molecular particles in the sewage. When the filling rate is 90% and the ceramic thickness exceeds 8 mm,the sewage turbidity removal rate exceeds 90%,and the filtered sewage turbidity is below 10 NUT,satisfying the industrial and agricultural requirements for water. Based on adsorption,screening-filter cake-deep bed filtration mechanism,a filtration mechanism model of the multi-layer cross-hole and through-hole structures is established. The multi-layer cross-hole alumina-based ceramics with submicron and micron-sized holes perform better in terms of permeability and filtration ability,compared to through-hole alumina filtration ceramics,possessing higher potential for sewage treatment applications. This research provides valuable reference for the application of micro-extrusion 3D printing technology in the field of porous ceramic filtration.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |