Pré-cloração associada à adsorção em carvão ativado em pó e flotação por ar dissolvido na remoção de microcistina presente em três diferentes concentrações em águas provenientes de reservatório eutrofizado / Prechlorination associated to adsorption with powdered activated carbon and dissolved air flotation in the removal of three concentrations of microcystin present in eutroficated reservoir water

AUTOR(ES)
DATA DE PUBLICAÇÃO

2008

RESUMO

The disordered growth of cities, the use of planting areas near the water sources and the launch of domestic and industrial wastewater without treatment are the main sources of water bodiespollution. Such pollution contributes to increase the nutrient loading in the water bodies. In association with climatic factors, this enrichment of nutrient provides suitable conditions for the bloom of potentially toxic algae. Thus, increases the concern over to develop treatment techniques that provide water quality able to ensure the health of the consumer population. In this research, waters were prepared with different concentrations of microcystin and some treatments were tested in bench scale. These tests consisted in prechlorination, adsorption on powdered activated carbon, coagulation/flocculation, dissolved air flotation and centrifugation. The diagram of treatment with activated carbon application after the rapid mix showed better results of apparent color, turbidity and residual concentration of microcystin. The influence of the concentration of microcystin in the simulated treatments was evaluated. It was found that for 104.92 µg/L of microcystin the application of 3.0 mgCL IND.2/L (10 seconds before rapid mix) and 30 mg/L of PAC (after a quick mixture) were not able to reduce the concentration of microcystin to less than 1 µg/L, as the limit established by Order 518/04 of the Health Ministry. Thus, it was decided to estimate the minimum dosage of powdered activated carbon (PAC) according to the initial concentration of microcystin found in the three prepared waters. The residual concentration of microcystin in each water, after the estimated dosage application of PAC was: Water 1 = 0.80 µg/L; Water 2 = 0.82 µg/L; Water 3 = 0, 23 µg/L.

ASSUNTO(S)

flotação por ar dissolvido adsorção pré-cloração water treatment prechlorination dissolved air flotation powdered activated carbon carvão ativado em pó microcystin microcistina adsorption tratamento de água

Documentos Relacionados