Publicação
Sludge treatment by Earthworm-Enhanced reed beds towards smart-cities
| Resumo: | This study explored an innovative approach for sewage sludge management using sludge treatment reed bed (STRB) enhanced with earthworms (W-STRB). To the authors’ knowledge, it was the first evaluation of STRB with earthworms under temperate climate (Portugal). The research included experiments in Beirolas wastewater treatment plant (pilot-scale) and Horto greenhouse at ISA (bench-scale). Beirolas pilot-scale was assessed for one year of feeding (24 cycles, mean sludge loading rate (SLR): 43.59 ± 14.49 kg of dry solids (DS) per m2.year) and 132 days of final resting. Four types of units were tested including planted unit with earthworms (WP), planted unit without earthworms (P), without plant with earthworms (W) and control unit without plants and earthworms (C), all replicated. In Beirolas pilot-scale, the plant species was Arundo donax and the earthworm was Eisenia fetida. In Horto bench-scale, two plant species were tested, Arundo donax and Phragmites australis. Planted units included Eisenia fetida earthworms and an additional unit without plants or earthworms was used as control. The bench-scale was studied for six months of feeding (50, 60, and 70 kg.DS.m-2.year-1) and two months of resting. Beirolas experiment showed that DS of all units were over 70 % while volatile solid content (VS) reached the minimum content at 53 % in the WP unit indicating higher stabilization in the presence of earthworms. A synergistic impact of earthworms could also increase plant biomass production by 30 % in the WP unit compared to the P unit. The WP unit showed significant reduction in the release mass (g) of pollutants in the drained water. The WP unit reduced 10 % the mass of heavy metal in the residual sludge compared to the P unit. The study emphasized earthworms’ positive role in STRB, and potential reuse of the residual sludge contributing to circular economy in smart cities. |
|---|---|
| Autores principais: | Gholipour, Amir |
| Assunto: | sludge dewatering earthworm Phragmites australis Arundo donax Eisenia fetida desidratação de lamas minhocas Phragmites |
| Ano: | 2024 |
| País: | Portugal |
| Tipo de documento: | tese de doutoramento |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório da Universidade de Lisboa |
| Resumo: | This study explored an innovative approach for sewage sludge management using sludge treatment reed bed (STRB) enhanced with earthworms (W-STRB). To the authors’ knowledge, it was the first evaluation of STRB with earthworms under temperate climate (Portugal). The research included experiments in Beirolas wastewater treatment plant (pilot-scale) and Horto greenhouse at ISA (bench-scale). Beirolas pilot-scale was assessed for one year of feeding (24 cycles, mean sludge loading rate (SLR): 43.59 ± 14.49 kg of dry solids (DS) per m2.year) and 132 days of final resting. Four types of units were tested including planted unit with earthworms (WP), planted unit without earthworms (P), without plant with earthworms (W) and control unit without plants and earthworms (C), all replicated. In Beirolas pilot-scale, the plant species was Arundo donax and the earthworm was Eisenia fetida. In Horto bench-scale, two plant species were tested, Arundo donax and Phragmites australis. Planted units included Eisenia fetida earthworms and an additional unit without plants or earthworms was used as control. The bench-scale was studied for six months of feeding (50, 60, and 70 kg.DS.m-2.year-1) and two months of resting. Beirolas experiment showed that DS of all units were over 70 % while volatile solid content (VS) reached the minimum content at 53 % in the WP unit indicating higher stabilization in the presence of earthworms. A synergistic impact of earthworms could also increase plant biomass production by 30 % in the WP unit compared to the P unit. The WP unit showed significant reduction in the release mass (g) of pollutants in the drained water. The WP unit reduced 10 % the mass of heavy metal in the residual sludge compared to the P unit. The study emphasized earthworms’ positive role in STRB, and potential reuse of the residual sludge contributing to circular economy in smart cities. |
|---|