Investigation of covers and chemical treatment for the suppression of cyanobacteria in water treatment systems

Abstract

Algal growth in water treatment plants can lead to the introduction of toxin and odour compounds from cyanobacteria and causes filter fouling. Here, we investigate the use of woven polypropylene covers and a proprietary copper sulfate formulation (EarthTec) to prevent algal growth within mesocosms designed to simulate settling basins. Chlorophyll a, soluble nutrients, weather patterns and cyanobacterial gene abundance were measured. The covers suppressed algal and cyanobacterial growth in mesocosms, likely due to a combination of light blockage and prevention of insects from entering the mesocosms. In contrast, mesocosms amended with EarthTec exhibited little difference from the control mesocosms in terms of algal growth. qPCR analysis revealed that only a small fraction of cyanobacteria in the system contained genes necessary for the production of the microcystin toxin. Despite differences between mesocosms and full‐scale settling basins, the data here suggest that woven covers can suppress algal growth while minimising evaporative water losses.

Clarificador de fluxo ascendente em pedregulho com cinco camadas para tratamento de água bruta com presença de algas: estudo piloto na estação de tratamento de água Castello Branco/PE

“…O seu desenvolvimento depende de alguns fatores, como luz solar e aporte de nutrientes, principalmente fósforo e nitrogênio, sendo o uso do solo na bacia de drenagem para o reservatório um importante fator de contribuição para a proliferação de algas (NICHETTI et al, 2022). A presença de algas em mananciais utilizados para o abastecimento pode representar https://doi.org/10.5327/276455760301004 sérios problemas para os administradores dos sistemas de distribuição de água (BOX et al, 2021).…”