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1.
Environ Res ; 241: 117661, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37980992

RESUMO

Two advanced oxidation processes (AOPs), namely ozone/H2O2 and UV/H2O2, were tested at pilot scale as zero-liquid-discharge alternative treatments for the removal of microbiological (bacteria and viruses), chemical (compounds of emerging concern (CECs)) and genotoxic responses from tertiary municipal wastewater for indirect potable reuse (IPR). The AOP treated effluents were further subjected to granular activated carbon (GAC) adsorption and UV disinfection, following the concept of multiple treatment barriers. As a reference, a consolidated advanced wastewater treatment train consisting of ultrafiltration, UV disinfection, and reverse osmosis (RO) was also employed. The results showed that, for the same electrical energy applied, the ozone/H2O2 treatment was more effective than the UV/H2O2 treatment in removing CECs. Specifically, the ozone/H2O2 treatment, intensified by high pressure and high mixing, achieved an average CECs removal efficiency higher than UV/H2O2 (66.8% with respect to 18.4%). The subsequent GAC adsorption step, applied downstream the AOPs, further improved the removal efficiency of the whole treatment trains, achieving rates of 98.5% and 96.8% for the ozone/H2O2 and UV/H2O2 treatments, respectively. In contrast, the ultrafiltration step of the reference treatment train only achieved a removal percentage of 22.5%, which increased to 99% when reverse osmosis was used as the final step. Microbiological investigations showed that all three wastewater treatment lines displayed good performance in the complete removal of regulated and optional parameters according to both national and the European Directive 2020/2184. Only P. aeruginosa resulted resistant to all treatments with a higher removal by UV/H2O2 when higher UV dose was applied. In addition, E. coli STEC/VTEC and enteric viruses, were found to be completely removed in all tested treatments and no genotoxic activity was detected even after a 1000-fold concentration. The obtained results suggest that the investigated treatments are suitable for groundwater recharge to be used as a potable water source being such a procedure an IPR. The intensified ozone/H2O2 or UV/H2O2 treatments can be conveniently incorporated into a multi-barrier zero-liquid-discharge scheme, thus avoiding the management issues associated with the retentate of the conventional scheme that uses reverse osmosis. By including the chemical cost associated with using 11-12 mg/L of H2O2 in the cost calculations, the overall operational cost (energy plus chemical) required to achieve 50% average CECs removal in tertiary effluent for an hypothetical full-scale plant of 250 m3/h (or 25,000 inhabitants) was 0.183 €/m3 and 0.425 €/m3 for ozone/H2O2 and UV/H2O2 treatment train, respectively.


Assuntos
Água Potável , Ozônio , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Peróxido de Hidrogênio/química , Escherichia coli , Oxirredução , Carvão Vegetal , Purificação da Água/métodos , Ozônio/química , Poluentes Químicos da Água/química , Raios Ultravioleta
2.
Chemosphere ; 239: 124635, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31514013

RESUMO

A comprehensive pilot study was carried out to experimentally assess the potential of newly developed treatment trains integrating two-stage AOPs and biofiltration to reach potable reuse water quality standards from municipal wastewater. The processes consisted of a two-stage AOPs with (carbon or limestone) biofiltration, the first AOP (O3/H2O2) serving as pre-treatment to biofiltration and the second AOP (UV254/H2O2) serving as post-biofiltration finishing step to ensure advanced disinfection. A comprehensive monitoring campaign was put in place resulting from the combination of targeted, non-targeted and suspect screening measurements. It was found that 13 organic micropollutants were detected from a list of 219 suspects although at ng/L level only. For the treatment conditions piloted in this study (O3 = 13 ±â€¯0.5 mg/L, H2O2 = 11 ±â€¯0.4 mg/L for the O3/H2O2 process, and UV = 410 ±â€¯63.5 mJ/cm2, H2O2 = 5 mg/l for the UV254/H2O2 process), it was possible to estimate the overall removal efficacy for each unit process, which was found to follow this order: RO (99%)  > BAC (87%) > O3-H2O2 (78%)  > BAL (67%)  > UV/H2O2 (43%)  > AOP contact chamber (19%)  > UF(0%), with the treatment train integrating two AOPs and granular biofiltration with activated carbon (O3/H2O2 + BAC + UV254/H2O2) showing superior performance with a 99% abatement in total micropollutants. No ecotoxicologically-positive response was generally observed for any of the effluent samples from the tested trains, even when pre-concentration factors up to 100-1000 times were employed to increase the sensitivity of the bioassay methods.


Assuntos
Água Potável/química , Filtração/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Carvão Vegetal/química , Desinfecção , Peróxido de Hidrogênio/química , Oxirredução , Ozônio/química , Projetos Piloto , Raios Ultravioleta
3.
Water Sci Technol ; 68(8): 1715-22, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24185051

RESUMO

In this paper, the physico-chemical treatment of municipal wastewater for the simultaneous removal of pollutant indicators (chemical oxygen demand (COD) and total coliforms) and organic contaminants (total phenols) was investigated and assessed. A secondary settled effluent was subjected to coagulation, disinfection and absorption in a multifunctional reactor by dosing, simultaneously, aluminum polychloride (dose range: 0-150 µL/L), natural zeolites (dose range: 0-150 mg/L), sodium hypochlorite (dose range: 0-7.5 mg/L) and powder activated carbon (dose range: 0-30 mg/L). The treatment process was optimized using computational fluid dynamics (CFD) and response surface methodology. Specifically, a Latin square technique was employed to generate 16 combinations of treating agent types and concentrations which were pilot tested on an 8 m(3)/h multifunctional reactor fed by a secondary effluent with COD and total coliform concentrations ranging from ≈20 to 120 mg/L and from 10(5) to 10(6) CFU/100 mL, respectively. Results were promising, indicating that removal yields up to 71% in COD and 5.4 log in total coliforms were obtained using an optimal combination of aluminum polychloride (dose range ≈ 84-106 µL/L), powder activated carbon ≈ 5 mg/L, natural zeolite (dose range ≈ 34-70 mg/L) and sodium hypochlorite (dose range ≈ 3.4-5.6 mg/L), with all treating agents playing a statistically significant role in determining the overall treatment performance. Remarkably, the combined process was also able to remove ≈ 50% of total phenols, a micropollutant known to be recalcitrant to conventional wastewater treatments.


Assuntos
Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Compostos de Alumínio/química , Análise da Demanda Biológica de Oxigênio , Simulação por Computador , Desinfecção , Enterobacteriaceae , Desenho de Equipamento , Projetos Piloto , Águas Residuárias/química , Águas Residuárias/microbiologia , Zeolitas
4.
Cancer Res ; 50(15): 4501-3, 1990 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-2369729

RESUMO

The efficacy of an originally developed photodynamic approach, using topical administration of tetraphenylporphinesulfonate as the photosensitizer, was evaluated in a series of 292 basal cell carcinoma lesions (less than 2-mm thick) in 50 treated patients. The lack of indication for conventional therapies was the main selection criterion. The photosensitizing agent (2% solution) was topically applied at 0.1 ml/cm2, followed by light irradiation with a dye laser emitting at 645 nm (120 or 150 J/cm2). After initial treatment, all lesions responded, with 273 (93.5%) complete responses. Recurrences were observed in 29 (10.6%). A second application of photoradiation was performed in 15 persistent lesions and 11 relapsed lesions, producing 19/26 complete responses. Our results suggest that this technique can be considered a promising alternative treatment modality in selected cases of superficial basal cell carcinomas.


Assuntos
Carcinoma Basocelular/tratamento farmacológico , Fotoquimioterapia , Porfirinas/uso terapêutico , Radiossensibilizantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Biópsia , Carcinoma Basocelular/patologia , Seguimentos , Humanos , Neoplasias Cutâneas/patologia
6.
Acta Oncol ; 27(5): 575-8, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3203013

RESUMO

Fifteen patients underwent resection of the whole glans surface with laser microsurgical technique from May 1983 to September 1987. The operations were performed in one stage in 11 cases and in two stages in 4. In 3 cases the resected lesions represented multiple dysplasia grade III or carcinoma in situ, in 1 case hyper/parakeratosis and penile horn, and in 11 cases superficial squamous cell carcinoma. In 8 cases primary superficial and flat tumors occupied more than half the circumference of the organ, and in the remaining 7 cases there were flat, superficial residues after systemic chemotherapy for exophytic, non-infiltrating carcinomas. The CO2 laser beam was used under constant microscopic visual control at a mean output power of 20W, CW or pulsed for the tissue excision from the meatus to the sulcus level. Maximum depth of resection was 2.6 mm. Postoperative external radiotherapy (60 Gy) was given in the first case of the series (microscopically invasive cancer). Satisfactory cosmetic and functional results were observed in all cases. During the follow-up period, ranging from 2 to 48 months, persistent cancer was found at the perimeatal area in 1 case 4 months after laser resection. The procedure can be considered for conservative treatment of wide or multiple superficial lesions of the glans penis.


Assuntos
Terapia a Laser , Neoplasias Penianas/cirurgia , Pênis/cirurgia , Adulto , Idoso , Humanos , Masculino , Microcirurgia , Pessoa de Meia-Idade
7.
Int J Biol Markers ; 2(3): 161-8, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2453592

RESUMO

A double-determinant radioimmunoassay for the detection of circulating antigens associated with human ovarian carcinoma was developed using two monoclonal antibodies: MOv2 and MOv8 employed respectively as catcher and tracer. The development of the method through three different procedures enabled us to detect the presence of CaMOv2-CaMOv8 carrying molecules in 14 out of 15 ascitic fluids from ovarian carcinoma patients whose tumors were found to be positive with MOv2 and MOv8 monoclonal antibodies by immunofluorescence. Moreover, 13 out of 15 ovarian carcinoma patients presented high levels of antigen in their serum (60-170 Ua/ml). Low levels of antigen were observed in the normal population, the values ranging from 30-40 Ua/ml. However, in 13 out of 100 apparently healthy women high levels of antigen were found in the serum.


Assuntos
Anticorpos Monoclonais , Antígenos de Neoplasias/análise , Biomarcadores Tumorais/sangue , Carcinoma/diagnóstico , Epitopos/análise , Neoplasias Ovarianas/diagnóstico , Adulto , Animais , Especificidade de Anticorpos , Antígenos de Neoplasias/imunologia , Antígenos Glicosídicos Associados a Tumores , Líquido Ascítico/análise , Carcinoma/sangue , Epitopos/imunologia , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Radioimunoensaio/métodos
8.
Tumori ; 73(1): 19-23, 1987 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-3824529

RESUMO

In photodynamic therapy, systemic administration of photosensitizing agents induces cutaneous photosensitization in patients. This side-effect can be avoided by topical administration of the agents when only surface lesions are involved. A hydroalcoholic solution of tetrasodium-meso-tetraphenylporphinesulfonate (TPPS) containing Azone, a percutaneous penetration enhancer, was investigated to evaluate its photosensitizing potential in the treatment of 33 primary and recurrent neoplastic lesions of the skin. A complete remission was obtained of lesions with clinical thickness of less than 2 mm. Treatment effectiveness depends on both light and drug penetration through skin. Further studies are in progress to optimize treatment parameters.


Assuntos
Fotoquimioterapia , Porfirinas/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Administração Tópica , Idoso , Idoso de 80 Anos ou mais , Azepinas/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Avaliação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Porfirinas/administração & dosagem , Neoplasias Cutâneas/patologia
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