RESUMO
Electrochemical oxidation of tannery effluent was carried out in batch, batch recirculation and continuous reactor configurations under different conditions using a battery-integrated DC-DC converter and solar PV power supply. The effect of current density, electrolysis time and fluid flow rate on chemical oxygen demand (COD) removal and energy consumption has been evaluated. The results of batch reactor show that a COD reduction of 80.85% to 96.67% could be obtained. The results showed that after 7 h of operation at a current density of 2.5 A dm(-2) and flow rate of 100 L h(-1) in batch recirculation reactor, the removal of COD is 82.14% and the specific energy consumption was found to be 5.871 kWh (kg COD)(-1) for tannery effluent. In addition, the performance of single pass flow reactors (single and multiple reactors) system of various configurations are analyzed.
Assuntos
Resíduos Industriais , Curtume , Eliminação de Resíduos Líquidos/métodos , Análise da Demanda Biológica de Oxigênio , Conservação de Recursos Energéticos , Fontes de Energia Elétrica , Eletrólise , Oxirredução , Energia SolarRESUMO
BACKGROUND: Wound healing occurs as a fundamental response to tissue injury. Several natural products have been shown to accelerate the healing process. AIM: To observe the efficacy of topical administration of an ethanolic extract of Ageratum conyzoides on cutaneous wound healing in rats. METHODS: An ethanolic extract of A. conyzoides was prepared, and its wound-healing efficacy on rats was studied. An open excision wound was made on the back of each rat, and 200 µL (40 mg/kg body weight) of the A. conyzoides extract was applied topically once daily to the treated wounds. The control wounds were treated with 200 µL of 50% ethanol. The wound tissues formed were removed at 4, 8 and 12 days after wounding, and biochemical parameters such as DNA, total protein, total collagen, hexosamine and uronic acid were estimated. The extent of epithelialization and the tensile strength of the wounded tissues were also measured. RESULTS: The A. conyzoides extract increased cellular proliferation and collagen synthesis. Wounds treated with the extract were found to heal much faster, based on the improved rates of epithelialization and wound contraction, and on the histopathological results. A 40% increase in the tensile strength of the treated tissue was seen. CONCLUSIONS: Topical application of A. conyzoides accelerates the rate of wound healing.
Assuntos
Ageratum/química , Colágeno/metabolismo , Extratos Vegetais/farmacologia , Pele/lesões , Cicatrização/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Hexosaminas/metabolismo , Masculino , Modelos Animais , Ratos , Ratos Wistar , Pele/metabolismo , Pele/patologia , Resistência à Tração , Ácidos Urônicos/metabolismo , Cicatrização/fisiologiaRESUMO
Ozonation of leather dye effluent for removal of color and COD reduction covering wide range in operating parameters forms the scope of the present work. The influence of parameters such as influent pH, ozone flow rate and initial effluent concentration on ozonation efficiency has been critically examined. It has been observed from the present investigation that a maximum of COD removal efficiency of 92% has been achieved under optimum operating conditions. Further the biodegradability index of the tannery effluent has increased from an initial value of 0.18 to 0.49 during ozonation indicating favorable adaptation of ozonation as a primer to the biochemical technique to enhance the efficiency of biochemical treatment.
