Textile effluente treatment though oxidation via activated humidity

Diversos problemas envolvem as estações de tratamento de efluentes têxteis, principalmente o baixo nível de eficiência quanto a remoção da cor. Em função de normas mais rigorosas que estão sendo estabelecidas, as indústrias têxteis têm que encontrar métodos efetivos para a descoloração de seus efluentes. O presente trabalho investigou através de estudos em laboratório, a remoção de cor destes efluentes através da oxidação por via úmida ativada (Processo de Oxidação Avançada-AOP) utilizando como oxidante o peróxido de hidrogênio, ativado pela radiação ultravioleta. A fotodegradação foi realizada em batelada em um reator equipado com uma lâmpada de vapor de mercúrio de média pressão, de imersão. Três diferentes doses de peróxido de hidrogênio foram testadas (15, 30 e 45 mg/L) em amostras com diferentes pHs (3, 7 e 11). A degradação da cor mostrou seguir uma cinética de pseudo primeira ordem, sendo as condições mais adequadas para o pH alcalino, na presença de 45 mg/L de H2O2.Several problems are found in the textile effluent treatment stations, mainly the low level of efficiency concerning color removal. As a result of more rigorous standards that have been established the textile industries are forced to find effective methods for discoloration of their effluents. This work concerns a laboratory investigation on the removal of color from these effluents through oxidation by activated wet process, (Advanced Oxidation Process-OAP), using hydrogen peroxide as an oxidizing agent, activated by ultraviolet radiation. Photo-degradation was carried out in a bark in a reactor equipped with an immersion mercury vapor lamp at medium pressure. Three different dosages of hydrogen peroxide were tested (15, 30 and 45 mg/L) using samples with different pHs (3, 7, 11). Color degradation proved to follow a kinetics of pseudo first order, being the most appropriate conditions for an alkaline pH, in the presence of 45 mg/L of H2O2

UV/H2O2 process as post-treatmentfor removal of color and polishing end in textile wastewater

Several problems are involved the treatment plants of textile effluents, mainly the low efficiency of color removal. This paper presents an alternative of post-treatment by UV/H2O2 process, for color removal in biologically treated textile effluents. The tests were performed in a photochemical reactor and samples were taken at different times to perform analyses. Using 250 mgH2O2.L-1, 96% removal of color was verified, indicating the dyes degradation. A reduction of 84% of aromatics compounds, 90% of TSS removal, and a further reduction of the organic fraction were observed, demonstrating that the process is effective as a post-treatment of effluents from textile industries

STIRAP transport of Bose-Einstein condensate in triple-well trap

The irreversible transport of multi-component Bose-Einstein condensate (BEC) is investigated within the Stimulated Adiabatic Raman Passage (STIRAP) scheme. A general formalism for a single BEC in M-well trap is derived and analogy between multi-photon and tunneling processes is demonstrated. STIRAP transport of BEC in a cyclic triple-well trap is explored for various values of detuning and interaction between BEC atoms. It is shown that STIRAP provides a complete population transfer at zero detuning and interaction and persists at their modest values. The detuning is found not to be obligatory. The possibility of non-adiabatic transport with intuitive order of couplings is demonstrated. Evolution of the condensate phases and generation of dynamical and geometric phases are inspected. It is shown that STIRAP allows to generate the unconventional geometrical phase which is now of a keen interest in quantum computing.Comment: 9 pages, 6 figures. To be published in Laser Physics (v. 19, n.4, 2009