Navegando por Assunto "Tratamento de água residuária"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Adsorção de cromo hexavalente por carvão ativado granulado comercial na presença de surfactante aniônico (LAS)
(Universidade Federal do Pará, 2011-09-22) SILVA, Maria Vitória Roma da; CARVALHO, Samira Maria Leão de; http://lattes.cnpq.br/6192858937057152
The hexavalent chromium removal from solutions of anionic surfactant (LAS) by granular activated carbon (GAC) commercial was studied. At CAG characterization was used ASTM standard method (Sauter mean diameter, dDMS e pH) and method BET (S, specific surface area). Adsorbent surface group and PCZ were determined by the method of Boehm and potentiometric titration, respectively. The adsorbent characterization results: dDMS=2.4 mm, pH=9.0,S=677.4 m²/g; basic groups (70%) compared with the acidic groups and PCZ in the range (4.8 – 8.6). Tests of adsorption of the surfactant LAS were carried out in shaker (140 rpm/24 h./27ºC), 2.0 g CAG/50 mL, the LAS concentration were determined by methylene blue standard method. The removal results versus initial concentration and removal versus time of all LAS concentrations were more than 99%. The adsorption of Cr(VI) (5 – 20 mg/L) were carried out in thermostatic bath (140 rpm/27ºC); 2,0 g CAG/50 mL; 1 and 24 hours of processing; without and with addition of surfactant (70, 140, 210, 280, 350, 533 and 700 mg/L). The initial e residual concentrations of metal were determined by 1,5-diphenylcarbazide colorimetric method. The metal removal without the addition of LAS was not satisfactory values were obtained, around 15%. The metal removal with surfactant reached values, around 70% to the lowest metal concentration (5 mg/L) and between (58-65%) for the other concentrations.
Acesso aberto (Open Access)
Verificação da tratabilidade de água residuária oriunda de beneficiamento do açaí por processo físico-químico
(Universidade Federal do Pará, 2016-04-15) FEIO, Vanessa Farias; MENDONÇA, Neyson Martins; http://lattes.cnpq.br/7534816053779593
This work aims to study the wastewater treatability coming from açaí processing plant, trougth jar test assay to get the best conditions for the physical-chemical wastewater treatment. For this, two experimental steps was done:1) Quantitative and qualitative characterization of raw wastewater to elaborate flow hydrograph and hydric balance. 2) Assay coagulation/flocculation/oxidation on jar test using hydrated lime, tannin, sodium hypochlorite, polyaluminium cloride and polymer. In treatability test dosage was varied for each product and analyzed in the clarified effluent variables: pH, apparent color, turbidity and COD. It was also determined the treated effluent quality index and the qualitative characterization of effluent of the proposed treatment, beyond the physical characterization of the sludge. Furthermore, it was estimated monthly cost of chemicals products for proposed treatment. By the results for wastewater quantitative characterization were obtained flow of Qméd = 305 L/h; Qmax = 521 L/h and Qmin = 183 L/h and qesp. of 0.51 L/kg.d. To the water balance was found that weight of water used is 112.4 ton/d, generating 7.30 ton/d of wastewater, water in the pulp mass equal to 49.36 ton/d and water loss of 55.81 ton/d. For treatability tests the best result was obtained for the combination polyaluminium (18mg/L) and polymer (30 mg/l) at pH 8.0, resulting in apparent color removal 98.5%; 99.8% of turbidity and COD equal to 90% . In the physical characterization of sludge was found values: density of 1.002 and specific mass equal to 1001.8 kg/m³, moisture content of 98.9%, and the SV/ST equal to 73%. In the cost estimate with chemical products was obtained R$4,77/month, representing R$0,022/m³ of treated effluent. We conclude that this effluent treatment is viable for physical-chemical treatment process.