Programa de Pós Graduação em Recursos Hídricos e Saneamento Ambiental, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Departamento de Química e Física, Universidade de Santa Cruz do Sul, Santa Cruz do Sul, Brazil.
Environ Technol. 2022 Apr;43(9):1370-1380. doi: 10.1080/09593330.2020.1830181. Epub 2020 Oct 6.
This study evaluated the performance of urban wastewater treatment in pilot-plant by an integrated system consisting of anaerobic reactor, microalgae cultivation, Venturi tube ozone recirculation, coagulation/flocculation with tannin-based agent natural coagulant, and dissolved air flotation (DAF). Ozone concentrations (without ozone, 0.13 and 0.25 mg O/mg of biomass) and tannin dosages (65, 85 and 105 mg/L) were evaluated regarding microalgae separation and their influences on wastewater treatment performance. During the experiments, it was verified that the treatment efficiency increased when ozone was applied and with higher tannin dosages. The best results were found with 0.13 mg O/mg of biomass and 105 mg/L of tannin, obtaining excellent removal of turbidity removal (99.4%), apparent colour at 420 nm (94.5%), TN (83.2%), N-NH (100%), TOC (86.8%), BOD (86.5%) and COD (100%), 47.6% reduction in electric conductivity, 46.1% in TDS, 66.4% TP removal for the integrated system and 84% microalgae biomass recovery were obtained. Our results showed that the system proved to be a viable alternative for the treatment of urban wastewater and the recovery of microalgae through the insertion of ozone via Venturi tube combined with tannin-based agent.
本研究通过一个集成系统评估了城市污水处理厂的中试性能，该系统由厌氧反应器、微藻培养、文丘里管臭氧再循环、单宁基天然混凝剂的混凝/絮凝以及溶气浮选（DAF）组成。评估了臭氧浓度（无臭氧、0.13 和 0.25 mg O/mg 生物质）和单宁剂量（65、85 和 105 mg/L）对微藻分离及其对废水处理性能的影响。在实验过程中，验证了当施加臭氧和使用更高单宁剂量时，处理效率会增加。当臭氧用量为 0.13 mg O/mg 生物质且单宁用量为 105 mg/L 时，得到了最佳结果，浊度去除率（99.4%）、420nm 表观色（94.5%）、TN（83.2%）、N-NH（100%）、TOC（86.8%）、BOD（86.5%）和 COD（100%）、电导率降低 47.6%、总溶解固体降低 46.1%、TP 去除率为 66.4%，综合系统中微藻生物量回收率为 84%。结果表明，该系统通过文丘里管插入臭氧与单宁基试剂相结合，为处理城市废水和回收微藻提供了一种可行的替代方法。
