Marluce Teixeira Andrade Queiroz

Solar energy for wastewater treatment: review of international technologies and their applicability in Brazil

Several studies have reported the adverse effects of recalcitrant compounds and emerging contaminants present in industrial effluents, which are not degradable by ordinary biological treatment. Many of these compounds are likely to accumulate in living organisms through the lipid layer. At concentrations above the limits of biological tolerance, these compounds can be harmful to the ecosystem and may even reach humans through food chain biomagnification. In this regard, advanced oxidation processes (AOPs) represent an effective alternative for the removal of the pollutants. This study focused on the AOP involving the use of ultraviolet radiation in homogeneous and heterogeneous systems. Based on the literature review, comparisons between natural and artificial light were established, approaching photoreactors constructive and operational characteristics. We concluded that the high availability of solar power in Brazil would make the implementation of the AOP using natural solar radiation for the decontamination of effluents feasible, thereby contributing to clean production and biodiversity conservation. This will serve as an important tool for the enforcement of environmental responsibility among public and private institutions.

CASE STUDY: SPATIOTEMPORAL ANALYSIS OF THE CALADINHO BROOK, PIRACICABA'S RIVER WATERSHED, MINAS GERAIS, FOR PUBLIC SUPPLY

The surface waters are subject to damage caused by the discharge of domestic and industrial sewage and by the precariousness of collection and disposal syste...

AVALIAÇÃO DO ESTADO TRÓFICO DO RIO PIRACICABA E SUA RELAÇÃO COM A UHE – SÁ CARVALHO, MG, BRASIL

The Piracicaba River, Minas Gerais, presents corresponding extension to 241 km from its source in the Serra do Caraca to its mouth on the Doce River, totaling an area of 6,000 km 2 with several tributaries leading to the River Watershed Piracicaba (RWP). Among the localities of RWP highlights the metropolitan area of the Vale do Aco, which has high level of human pressure on water body according to their production profile (mining, steel, reforestation with eucalyptus, etc.) affecting ecosystem health. In this study prioritized examine the issue of surface water quality with emphasis on the process of eutrophication based on the measurement of the phosphorus and nitrogen concentration in different stations, and P 1 (Fonseca), P 2 (Rio Piracicaba), P 3 (Nova Era), P 4 (Coronel Fabriciano) and P 5 (Ipatinga) located around the Sa Carvalho hydroelectric power plant (HPP- Sa Carvalho). Surface water samples were collected on quarterly basis in the period from July / 2007 to July / 2012, paying attention separates the relevant seasonality of rainfall, compared with changes in physical and chemical parameters and analyzing the influence of hydropower in quality water. The data were worked by analyzing the relationship between nitrogen and phosphorus (N: P), Trophic Status Index (TSI) for total phosphorus and the Trophic State Index (TSI) for chlorophyll a showing an increase of nutrients being identified eutrophied conditions in several campaigns possibly related to the discharge of sewage, agricultural activities and industrial wastewater. This approach is finalized explaining the need for enforcement actions to contain the disturbances aimed at sustainable development and preservation of that water body.

Análise espaço-temporal de parâmetros de qualidade da água no Rio Piracicaba, Minas Gerais, Brasil

O presente trabalho buscou verificar a contribuicao fisica, quimica e biologica do reservatorio da Usina Hidreletrica de Sa Carvalho, para o Rio Piracicaba, Bacia Hidrografica do Rio Doce, Minas Gerais. Realizaram-se coletas quadrimestrais da agua superficial (bruta), nos periodos de seca e chuva, entre novembro/2006 ate julho/2012, em quatro pontos de coletados localizados em Nova Era (P1), Timoteo (P2), Coronel Fabriciano (P3) e Ipatinga (P4) nas proximidades do seu desague no Rio Doce. As variaveis limnologicas foram coletadas e avaliadas de acordo com CETESB (2006) e APHA (2005), enquanto os dados pertinentes ao reservatorio foram obtidos atraves dos relatorios produzidos pela CEMIG (2012). Quanto ao reservatorio constatou-se que em sua area da captacao ocorrem atividades agropecuarias e extrativismo florestal com repercussoes, tais como, a desertificacao que promove alteracoes climaticas influenciando a concentracao das substâncias quimicas no corpo hidrico. Em todas as localidades desse estudo apurou-se IQA regular. Os piores resultados foram detectados na estacao seca explicitando relacao com a elevacao da turbidez indicando melhor correlacao em P4 sendo constatado que a reducao da precipitacao pluviometrica se constituiu em impeditivo para autodepuracao sendo identificadas condicoes de intenso assoreamento tambem a jusante da UHE – Sa Carvalho. Constatou-se que a geracao de energia eletrica nao e principal responsavel pela degradacao do manancial perdendo para a siderurgia, mineracao, esgoto sanitario e exploracao florestal. Entende-se que deve ser intensificado o programa de preservacao das areas degradadas e educacao ambiental visando o desenvolvimento sustentavel da regiao de estudo.

A Brief Review on the Importance use of Solar Energy in the Treatment of Recalcitrant Effluents Applying Advanced Oxidation Processes

Several studies have reported the adverse effects of persistent compounds in the wastewater, showing the fragility of the biologic treatment. Harmful effects for both aquatic biota and human being are caused by those compounds. In order to minimize the adverse environmental impacts, Advanced Oxidation Processes (AOPs) are used in the degradation of those pollutants to achieve high removal rates. In the present the comparisons between the efficiency of AOPs using natural and artificial Ultra Violet light (UV) were made based on the literature review, addressing constructive and operational characteristics of the reactors. The findings indicated that the high levels of solar energy, which are registered in different regions of Brazil, show the viability of the AOP using natural radiation to the decontamination of industrial effluents. Thus the inclusion of advanced oxidation in the treatment of wastewater could be considered as a significant contribution to the supported development in Brazil.