Sample records for gaseous wastes

Sample records 1 - 2 shown.


Gerenciamento de resíduos químicos e águas servidas no laboratório de isótopos estáveis do CENA/USP/ Chemistry waste and residues waters management at the stable isotope laboratory of the CENA/USP

Bendassolli, José Albertino; Máximo, Everaldo; Tavares, Glauco Arnold; Ignoto, Raquel de Fátima

Resumo em inglês A system for disposal and recovery of the main effluents and chemical waist from isotope separation plants and enriched compounds-15N and 34S production has been carried out at the Stable Isotope Laboratory (LIE) of the CENA/USP. Around four hundred thousand liters of effluents has been recovered yearly. Among the recovered chemical wastes, the more relevant are: ammonia; brome; ammonium and sodium sulfate; sodium hydroxide; sulfur dioxide; and hydrochloric acid. Chemical (mais) wastes containg recoverable heavy metals (Ag, Cr and Cu) and solvents (methanol, ethanol and acetone) are processed and recovered. Gaseous emissions, mainly H2S are used for recovery of heavy metals solutions. The minimization of the residues waters, as well the reduction of electric energy consume was established using a water deionization system. A cost/effect balance of the process is reported.

Scientific Electronic Library Online (Portuguese)


Estudo da degradação fotocatalítica de dimetil dissulfeto: avaliação estatistica do efeito do pH da temperatura e concentração do contaminante orgânico/ Assessment of the photocatalytic degradation of dimethyl disulfide: effect of pH, temperature and concentration of the organic contaminant

Dallago, Rogério Marcos; Domenech, Fabrício; Reolon, Joncimar; Di Luccio, Marco; Egues, Silvia Maria da Silva

Resumo em inglês This work aimed to assess the photocatalytic degradation of a model odor compound (dimethyl disulfide, DMDS), found in liquid and gaseous wastes of plants for processing poultry byproducts. The effect of pH and temperature on adsorption and photocatalytic degradation was evaluated through factorial experimental designs. The results suggest the presence of an optimum region for adsorption, at 45.0 ºC and pH 4.0. In the photocatalytic runs an optimum for temperature and pH was also observed. At 45 ºC and pH 4.0 the removal of DMDS was 99% after 60 min of irradiation.

Scientific Electronic Library Online (Portuguese)