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Application of Advanced Oxidation Processes to Wastewater Treatment

Lucas, Marco Paulo Gomes de Sousa
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
27.19%
Tese de Doutoramento em Química; This research contributes to the study and development of advanced oxidation technologies applied to two different problematic wastewaters: textile and winery wastewaters. In this dissertation the factors that influence the oxidation of the model compound of textile wastewaters, the azo dye Reactive Black 5 (RB5), and of the winery wastewaters were investigated. The first part of the thesis experimental work is dedicated to the decolorization of RB5 solutions. The RB5 dye was selected as model molecule to represent the concerned dye group because is widely used in the textile and paper industries, hardly biodegradable and inexpensive. Firstly, an experimental comparison among two photoxidation systems, Fenton/UV-C and ferrioxalate/H2O2/solar light, was performed. The variables considered were pH, H2O2 dosage, iron dosage, RB5 concentration and source of light. The experiments indicate that RB5 can be effectively decolorized using Fenton/UV-C and ferrioxalate/H2O2/solar light processes with a small difference between the two processes, 98.1 and 93.2%, respectively, after 30 minutes. Although the lesser difference in dye decolorization, significant increment in TOC removal was found with Fenton/UV-C process (46.4% TOC removal) relative to ferrioxalate/H2O2/solar light process (29.6% TOC removal). This fact reveals that UV-C low pressure mercury lamp although with its small effect on dye decolorization is particularly important in dye mineralization...

O diagnóstico de uma ETAR como suporte à decisão para a reutilização do efluente tratado - caso de estudo da ETAR de Coruche

Sousa, Gonçalo Nuno Santos Serrão
Tipo: info:eu-repo/semantics/masterthesis
Publicado em //2009 Português
Relevância na Pesquisa
27.19%
Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia; The main objective of this work was the assessment of the WWTP technical conditions, for treated wastewater reuse. Field data analyses carried out through the processing of wastewater flow daily records and the collection and characterization of wastewater and treated wastewater samples. This allowed to assess the wastewater hydraulic performance, wastewater and treated wastewater concentrations, percentage of pollution load reduction and treated wastewater quality, according to the requirements for discharge on water body and for irrigation use. Furthermore two experiments were made in order to assess the potential of treated wastewater reuse for irrigation, through its interaction with the soil and the plants. In trial experiment, treated wastewater induced a lower mineralization of BOW organic N and in some cases the potential N mineral immobilization. The field experiment showed that grass irrigation with treated wastewater resulted in an improved grass quality that may be enhanced with the application of sewage sludge in situ into the soil. The overall conclusion shows that treated wastewater possesses characteristics which allow its reuse as an alternative to discharge on water body.--------------------------------------Este trabalho teve como principal objectivo a avaliação das condições técnicas da ETAR de Coruche...

Biodegradability enhancement and detoxification of cork processing wastewater molecular size fractions by ozone

Santos, Diana; Silva, L.; Albuquerque, Antonio; Simoes, Rogerio; Gomes, Arlindo
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /11/2013 Português
Relevância na Pesquisa
36.71%
Cork boiling wastewater pollutants were fractionated by sequential use of four ultrafiltration membranes and five fractions were obtained: four retentates (>100, 50-100, 20-50 and 10-20 kDa) and one permeate (100 kDa corresponds to 56% of the organic load and the one with 100 to < 10 kDa and the chemical oxygen demand (COD) was from 3436 to 386 mg L-1. For biodegradability enhancement the best outcome of ozonation was obtained with compounds having molecular size >20 kDa and range from 5% up to 175% for applied ozone doses to COD ratios between 0.15 and 0.38.

Abundance and species composition of planktonic Ciliophora from the wastewater discharge zone in the Bahía Blanca Estuary, Argentina

Barría de Cao,María Sonia; Pettigrosso,Rosa; Parodi,Elisa; Freije,Rubén
Fonte: Fundação Zoobotânica do Rio Grande do Sul Publicador: Fundação Zoobotânica do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2003 Português
Relevância na Pesquisa
36.71%
The specific composition and abundance variation of the ciliate community from a wastewater discharge zone in the Bahía Blanca estuary, Argentina, were studied all throughout a year, from June 1995 to May 1996. The polluted area exhibited high values of particulate organic matter and nutrients, particularly phosphates. Aloricate ciliates were represented by 15 species belonging to the genera Strombidium Claparède & Lachmann, 1859; Strombidinopsis Kent, 1881; Cyrtostrombidium Lynn & Gilron, 1993; Strobilidium Schewiakoff, 1983; Lohmmanniella Leegaard, 1915 and Tontonia Fauré-Fremiet, 1914. Tintinnids were represented by nine species belonging to the genera Tintinnidium Kent, 1881, Tintinnopsis Stein, 1867 and Codonellopsis Jörgensen, 1924. The total abundance of aloricate ciliates reached a peak of 1,800 ind. 1-1 and the total abundance of tintinnids reached a peak of 9,400 ind. 1-1. Tintinnidium balechi Barría de Cao, 1981 was the most abundant ciliate in the community. Considerations on the presence and abundance of ciliates are made in relation to physicochemical and biochemical parameters.

Nitrous oxide emissions from an intermittent aeration activated sludge system of an urban wastewater treatment plant

Mello,William Z. de; Ribeiro,Renato P.; Brotto,Ariane C.; Kligerman,Débora C.; Piccoli,Andrezza de S.; Oliveira,Jaime L. M.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 Português
Relevância na Pesquisa
36.71%
This study investigated the emission of N2O during the sequential aerated (60-min) and non-aerated (30-min) stages of an intermittent aeration cycle in an activated sludge wastewater treatment plant (WWTP). N2O emission occurred during both stages; however, emission was much higher during aeration. Air stripping is the major factor controlling transfer of N2O from the sewage to the atmosphere. The N2O emissions exclusively from the aeration tank represented 0.10% of the influent total nitrogen load and the per capita emission factor was almost 3 times higher than that suggested by the IPCC for inventories of N2O emission from WWTPs.

Sweet potato tissue-epoxy resin composite biosensor for hydroquinone determination in photographic process wastewater

Lupetti,Karina O.; Zanotto-Neto,Giacomo; Fatibello-Filho,Orlando
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2006 Português
Relevância na Pesquisa
36.71%
A biosensor of graphite-epoxy resin-sweet potato tissue (source of polyphenol oxidase) was developed in this work. The evaluated compositions of graphite-epoxy resin-vegetable tissue were varied from 30 to 80% (m/m) graphite; from 5 to 60% (m/m) epoxy resin and from 5 to 20% (m/m) tissue. The cyclic and linear sweep voltammograms were obtained at a scan rate between 25 and 300 mV s-1 in the pH range from 3 to 8 in 0.1 mol L-1 phosphate buffer solutions. Several phenolic compounds were determined by the proposed biosensor and hydroquinone was determined in wastewater from photographic process. Relative standard deviations of 0.7% and 3.3% were obtained employing the same biosensor (n=10) and three different biosensors (n=10), respectively. Sensitivity and selectivity were evaluated employing the biosensor for hydroquinone with a lifetime of at least 6 months (more than 500 determinations).

Treatment of cattle-slaughterhouse wastewater and the reuse of sludge for biodiesel production by microalgal heterotrophic bioreactors

Maroneze,Mariana Manzoni; Barin,Juliano Smanioto; Menezes,Cristiano Ragagnin de; Queiroz,Maria Isabel; Zepka,Leila Queiroz; Jacob-Lopes,Eduardo
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 Português
Relevância na Pesquisa
36.71%
Microalgal heterotrophic bioreactors are a potential technological development that can convert organic matter, nitrogen and phosphorus of wastewaters into a biomass suitable for energy production. The aim of this work was to evaluate the performance of microalgal heterotrophic bioreactors in the secondary treatment of cattle-slaughterhouse wastewater and the reuse of microalgal sludge for biodiesel production. The experiments were performed in a bubble column bioreactor using the microalgae Phormidium sp. Heterotrophic microalgal bioreactors removed 90 % of the chemical oxygen demand, 57 % of total nitrogen and 52 % of total phosphorus. Substantial microalgal sludge is produced in the process (substrate yield coefficient of 0.43 mg sludge mg chemical oxygen demand?¹), resulting in a biomass with high potential for producing biodiesel (ester content of more than 99 %, cetane number of 55, iodine value of 73.5 g iodine 100 g?¹, unsaturation degree of ~75 % and a cold filter plugging point of 5 ºC).

Wastewater treatment by flotation

Puget,F.P.; Melo,M.V.; Massarani,G.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2000 Português
Relevância na Pesquisa
36.71%
This work deals with the performance analysis of a separation set-up characterized by the ejector-hydrocyclone association, applied in the treatment of a synthetic dairy wastewater effluent. The results obtained were compared with the results from a flotation column (cylindrical body of a hydrocyclone) operated both batch and continuously. As far as the experimental set-up studied in this work and the operating conditions imposed to the process, it is possible to reach a 25% decrease in the total effluent chemical oxygen demand (COD). This corresponds approximately to 60% of the COD of the material in suspension. The best results are obtained for ratios air flow rate-feed flow rate (Qair/Q L) greater then 0.15 and for ratios underflow rate-overflow rate (Qu/Qo) lower than 1.0.

Soft sensors with white- and black-box approaches for a wastewater treatment process

Zyngier,D.; Araújo,O.Q.F.; Lima,E.L.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2000 Português
Relevância na Pesquisa
36.71%
The increasing degradation of water resources makes it necessary to monitor and control process variables that may disturb the environment, but which may be very difficult to measure directly, either because there are no physical sensors available, or because these are too expensive. In this work, two soft sensors are proposed for monitoring concentrations of nitrate (NO) and ammonium (NH) ions, and of carbonaceous matter (CM) during nitrification of wastewater. One of them is based on reintegration of a process model to estimate NO and NH and on a feedforward neural network to estimate CM. The other estimator is based on Stacked Neural Networks (SNN), an approach that provides the predictor with robustness. After simulation, both soft sensors were implemented in an experimental unit using FIX MMI (Intellution, Inc) automation software as an interface between the process and MATLAB 5.1 (The Mathworks Inc.) software.

The study of protozoa population in wastewater treatment plants by image analysis

Motta,M.da; Pons,M.N.; Vivier,H.; Amaral,A.L.; Ferreira,E.C.; Roche,N.; Mota,M.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2001 Português
Relevância na Pesquisa
36.71%
Protozoa are important microorganisms for the ecosystem balance in wastewater treatment plants. A procedure for their semi-automated identification and counting based on image analysis is proposed. The main difficulty is segmentation of the protozoa as most of them are in contact with the sludge. The protozoa are characterized by the size of their silhouette (area and length) and three shape factors (elongation, circularity and eccentricity). They are identified after projecting the resulting 5D space into a 3D space of principal components. The rate of automated identification is actually higher than 50% for some of the species commonly found in activated sludge.

Simulation of an industrial wastewater treatment plant using artificial neural networks and principal components analysis

Oliveira-Esquerre,K.P.; Mori,M.; Bruns,R.E.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2002 Português
Relevância na Pesquisa
36.71%
This work presents a way to predict the biochemical oxygen demand (BOD) of the output stream of the biological wastewater treatment plant at RIPASA S/A Celulose e Papel, one of the major pulp and paper plants in Brazil. The best prediction performance is achieved when the data are preprocessed using principal components analysis (PCA) before they are fed to a backpropagated neural network. The influence of input variables is analyzed and satisfactory prediction results are obtained for an optimized situation.

Enhancement of the performance of an anaerobic sequencing batch reactor treating low-strength wastewater through implementation of a variable stirring rate program

Rodrigues,J. A. D.; Pinto,A. G.; Ratusznei,S. M.; Zaiat,M.; Gedraite,R.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2004 Português
Relevância na Pesquisa
36.71%
This work focuses on enhancement of the performance of an anaerobic sequencing batch reactor with a six-vertical-blade-disk-turbine impeller, containing granulated biomass treating low-strength synthetic wastewater, through a study of the feasibility of implementing a variable stirring rate program. The reactor was operated at 30ºC and a six-hour cycle was used to treat approximately 2.0 L of the synthetic substrate with a chemical oxygen demand (COD) of nearly 500 mg/L. Two different stirring rate program were implemented: a constant rate of 50 rpm and a variable rate consisting of 75 rpm for one hour, 50 rpm for four hours and 25 rpm for 0.5 hour. The last 0.5 hour of the cycle was used for the settling step. In both cases, a very short start-up period and unfiltered and filtered substrate removal efficiencies of 81% and 88%, respectively, were attained. However, use of the variable stirring rate enhanced efficiency of the reactor dynamics without impairing biomass morphology, thus resulting in a reduction in the total cycle time and a possible decrease in energy consumption. Additionally, a simplified model of the anaerobic metabolic activity, using apparent kinetic parameters, was proposed as a consecutive first-order kinetic model with substrate and total volatile acid residual concentrations in order to analyze how the variable stirring rate affects reactor performance.

A simplified analysis of granule behavior in ASBR and UASB reactors treating low-strength synthetic wastewater

Veronez,R. G.; Orra,A. A.; Ribeiro,R.; Zaiat,M.; Ratusznei,S. M.; Rodrigues,J. A. D.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2005 Português
Relevância na Pesquisa
36.71%
This work presents an analysis of the changes observed in granule characteristics of sludge in the treatment of synthetic wastewater at a concentration of about 500 mgCOD/L in batch, fed-batch (ASBR) and continuous (UASB) bench-scale reactors under similar experimental conditions. Physical and microbiological properties of the granules were characterized as average particle size and sedimentation time and by optical and epifluorescence microscopy. Several samples were analyzed in order to identify the morphologies. Granules from sequencing batch and fed-batch reactors, either with or without mechanical mixing, did not undergo any physical or microbiological changes. However, during the experiment granules from the UASB reactor agglomerated due to the formation and accumulation of a viscous material, probably of microbial origin, when operated at low superficial velocities (0.072, 0.10 and 0.19 m/h). When the superficial velocity was increased to 8.0-10.0 m/h by means of liquid-phase recirculation, the granules from the UASB reactor underwent flocculation and the microbiological characteristics changed in such a way that the equilibrium of microbial diversity in the inoculum was not maintained. As a result, the only reactor that maintained efficiency and good solids retention during the assays was the ASBR...

Anaerobic ammonium oxidation in a bioreactor treating slaughterhouse wastewater

Reginatto,V.; Teixeira,R. M.; Pereira,F.; Schmidell,W.; Furigo Jr,A.; Menes,R.; Etchebehere,C.; Soares,H. M.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2005 Português
Relevância na Pesquisa
36.71%
Ammonium oxidation was thought to be an exclusively aerobic process; however, as recently described in the literature, it is also possible under anaerobic conditions and this process was named ANAMMOX. This work describes the operation of a system consisting of a denitrifying reactor coupled to a nitrifying reactor used for removal of nitrogen from slaughterhouse wastewater. During operation of the denitrifying reactor an average nitrogen ammonium removal rate of 50 mg/Ld was observed. This biomass was used to seed a second reactor, operated in repeated fed batch mode, fed with synthetic medium specific to the growth of bacteria responsible for the ANAMMOX process. The nitrogen loading rate varied between 33 and 67 mgN/Ld and average nitrogen removal was 95% and 40%, respectively. Results of fluorescence in situ hybridization (FISH) confirmed the presence of anammox-like microorganisms in the enriched biomass.

Comparison between a conventional membrane bioreactor (C-MBR) and a biofilm membrane bioreactor (BF-MBR) for domestic wastewater treatment

Subtil,E. L.; Mierzwa,J. C.; Hespanhol,I.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 Português
Relevância na Pesquisa
36.71%
In this paper, the influence of biofilm carriers in a MBR on the performance of organic matter and nitrogen removal and the influence on membrane fouling were evaluated. The configurations studied included a Conventional Membrane Bioreactor (C-MBR) and a Biofilm Membrane Bioreactor (BF-MBR) operated in parallel, both fed with domestic wastewater. Regarding organic matter removal, no statistically significant differences were observed between C-MBR and BF-MBR, producing an effluent with a Soluble COD concentration of 27 ± 9.0 mgO2/L and 26 ±1.0 mgO2/L and BOD concentration of 6.0 ± 2.5 mgO2/L and 6.2 ± 2.1 mgO2/L, respectively. On the other hand, the BF-MBR produced a permeate with lower ammonia and total nitrogen concentrations, which resulted in a removal efficiency of 98% and 73%, respectively. It was also observed that the fouling rate was about 35% higher in the C-MBR than that for the BF-MBR, which also presented a reduction of total membrane resistance, about 29%, and increased operational cycle length around 7 days, compared to C-MBR.

Evaluation of sequential aerated treatment of wastewater from hardboard mill

Videla,S.; Isaacs,C.; Diez,M. Cristina
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1998 Português
Relevância na Pesquisa
36.71%
Wastewater from a hardboard mill characterized by a high organic content (15-30 g/L COD) was studied in a bench scale sequential aerated system in order to define a start up strategy. Inlet COD concentration varied from 0.5 to 25 g/L and the hydraulic retention time was maintained at 5 days. The sequential system proposed could reduce BOD, COD, TSS and phenol over 90% except when the inlet COD concentration was lower than 25 g/L.

Isolation of Rhodocyclus gelatinosus from poultry slaughterhouse wastewater

Ponsano,Elisa Helena Giglio; Lacava,Pedro Magalhães; Pinto,Marcos Franke
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2002 Português
Relevância na Pesquisa
36.71%
Four cultures of photosynthetic bacteria isolated from poultry slaughterhouse wastewater were identified as Rhodocyclus gelatinosus based on the following properties: reddish color of cultures in synthetic medium, presence of motility, slightly curved Gram-negative rods morphology, gelatin liquefying activity, utilization of citrate as carbon source and production of bacteriochlorophyl a and carotenoids of the spirilloxanthin alternative series. R. gelatinosus may represent a source of nutrients and pigments with application in poultry feed.

Chemical composition of Rhodocyclus gelatinosus biomass produced in poultry slaughterhouse wastewater

Ponsano,Elisa Helena Giglio; Lacava,Pedro Magalhães; Pinto,Marcos Franke
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2003 Português
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36.71%
Rhodocyclus gelatinosus R1 grew photoautotrophically in poultry slaughterhouse wastewater inside glass columns (90x670 mm) during 7 days at 31 ± 4ºC, under anaerobiosis and lightness supplied by daylight plus 3 (100W) incandescent and 4 (40W) fluorescent lamps. The culture was centrifuged (4,500xg/20 min) and lyophilized to originate a bacterial biomass with 7.1% moisture content. Chemical composition investigation showed 67.6% crude protein, 27.6% total carbohydrate, 0.6% lipids and 4.2% ash (dry weight). Amino acid composition of the biomass was similar to others described in the literature for Rhodocyclus gelatinosus and for other photosynthetic bacteria. Effluent COD removal after cultivation and elimination of the biomass was around 90%. The valuable chemical composition of Rhodocyclus gelatinosus R1 biomass and the high content in essential amino acids signs for the potential use of the product in poultry feed.

Nickel biosorption by Acinetobacter baumannii and Pseudomonas aeruginosa isolated from industrial wastewater

Rodríguez,Carlos E.; Quesada,Adolfo
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2006 Português
Relevância na Pesquisa
36.71%
Nickel biosorption ability was evaluated in two bacterial strains: Acinetobacter baumannii UCR-2971 and Pseudomonas aeruginosa UCR-2957, resulting in greatest adsorption at pH 4.5 and a residence time of 100 minutes. Biosorption isotherms showed that the process follows the Langmuir model. The maximum adsorption rates (Nmax) were 8.8 and 5.7 mg·g-1 for A. baumannii and P. aeruginosa, respectively; however, affinity constants suggest that P. aeruginosa (K=1.28) has higher affinity for nickel than A. baumannii (K=0.68). It is suggested that both strains could be used for wastewater treatment, as long as the concentration of Ni2+ is within the range of mg·L-1.

Evaluatin of metabisulfite and a commercial stee wool for removing chromium (VI) from wastewater.

GROMBONI, C. F.; DONATI, G. L; MATOS, W. O.; NEVES, E. F. A.; NOGUEIRA, A. R. de A.; NOBREGA, J. A.
Fonte: Enviromental Chemistry Letter, v. 8, p.73-77, 2010. Publicador: Enviromental Chemistry Letter, v. 8, p.73-77, 2010.
Tipo: artigo em periódico indexado (alice)
Português
Relevância na Pesquisa
36.71%
Efficiency of metabisulfite and a commercial steel wool as reducing agents in the removal of Cr(VI) from wastewaters was evaluated. Chromium( VI) was converted to Cr(III), precipitated with NaOH, and removed by filtration. A reduction of more than 1.0 x 10(5) and 4.0 x 10(5) fold in total Cr and the Cr(VI) concentrations, respectively, was observed by employing steel wool masses as low as 0.4420 g to 30-mL solutions of wastewater. Chromium(III) hydroxide obtained after the treatment was recycled and used as marker in cattle nutrition studies. The liquid residue obtained after the treatment was reused as precipitation agent replacing NaOH.; 2010