Energy recovery by anaerobic digestion of algal biomass from integrated microalgae/constructed wetland wastewater treatment

• Published in: Environmental science and pollution research international Vol. 30; no. 5; pp. 13317 - 13326
• Main Authors: Silveira, Elizandro Oliveira, Felizzola, Nathalia Mendes, Hickmann, Eugênia Vargas, Konrad, Odorico, Lutterbeck, Carlos Alexandre, Machado, Ênio Leandro, Rodrigues, Lúcia Ribeiro
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-01-2023
• Subjects: Anaerobiosis; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Biofuels; Biomass; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Microalgae; Research Article; Waste Disposal, Fluid; Waste Water Technology; Wastewater; Water Management; Water Pollution Control; Water Purification - methods; Wetlands; Microalgae and wastewaters; Biogas; Biomass; Constructed wetland
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-022-23019-3

The present study evaluated the potential for biogas generation from microalgae (MA) biomass and macrophytes used in vertical flow constructed wetlands (VFCW). The samples were obtained by separation and collection of MA after a hydraulic retention time of 14 days, frozen and taken to the laboratory, while the macrophytes of VFCW were obtained, by pruning, every 6 months. The obtained results presented reductions of 63.22% and 61.18% for COD and BOD
5
, respectively, and removal efficiencies of 53.91% for TP and 99.98% de N-NH
3
. Average biogas generation was 2322.51 NmL-gSV
−1
with 54.61% CH
4
(winter/2019), 4491.47 Nml-gSV
−1
with 57.17% CH
4
(spring/2019), 680.78 NmL-gSV
−1
with 16.04% CH
4
(summer/2020), and 681.0 NmL-gSV
−1
with 19.86% CH
4
(autumn/2020) for MA biomass and generation of biogas of 3826.70 NmL-gSV
−1
with 44.26% CH
4
for VFCW biomass in winter and spring/2019 and of 829.68 NmL-gSV
−1
with 17.06% CH
4
in summer and autumn/2020. Regarding electricity generation, the present work obtained 1.50 kWh/m
3
, therefore reaching similar values to other studies that used more traditional biomass sources.