A carregar...
Publicação
Removal of cyanobacteria and cyanotoxins from drinking water by powdered activated carbon adsorption/ultrafiltration
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 207.58 KB | Adobe PDF | |||
| 599.37 KB | Adobe PDF | |||
| 501.23 KB | Adobe PDF | |||
| 177.57 KB | Adobe PDF | |||
| 206 KB | Adobe PDF |
Autores
Orientador(es)
Resumo(s)
PAC/UF was investigated to remove the cyanobacterium Microcysis aeruginosa and
microcystins, focusing on toxins adsorption onto PAC and the combined effect of the water
organic and inorganic matrices, the cells removal and lysis by UF, and PAC contribution to
membrane fouling control and microcystins removal by PAC/UF.
The fine-grade mesoporous PAC presented high capacity and fast kinetics for microcystins
adsorption from ultrapure-water. In model and natural waters, NOM size governed
microcystins-NOM competition, and inorganics contribution was crucial. Main competitor
was NOM of closer size, hindering microcystins adsorption through a pore-blocking
mechanism. Ionic strength induced the competition of larger compounds and diminished the
competition of similar-sized compounds. Kinetic models confirmed the competing
mechanisms proposed based on kinetic and isotherm data.
UF ensured absolute removal of M. aeruginosa single-cells, although lysis was detected,
particularly with cell ageing. However, AOM-driven microcystins rejection
attenuated/avoided the permeate degradation. While not affecting the reversible fouling, PAC
improved the permeate quality and membrane irreversible-fouling, minimising the chemical
cleaning. The worst flux impairment was associated to polysaccharide-like AOM in
background inorganics, for which PAC was apparently ineffective.
PAC/UF performed better than PAC+C/F/S. For the usual concentrations of dissolved
microcystins in natural waters, 10-15 mgPAC/L achieved the WHO guideline-value.
Descrição
Tese dout., Ciências e Tecnologias do Ambiente, Universidade do Algarve, 2009
Palavras-chave
Teses Água potável Ultrafiltração Cianobactérias