São João da Madeira, Portugal
São João da Madeira, Portugal

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PubMed | University of Porto, Catholic University of Portugal and Centro Empresarial e Tecnologico
Type: Journal Article | Journal: Journal of hazardous materials | Year: 2016

Conventional wastewater treatment has a limited capacity to reduce antibiotic resistant bacteria and genes (ARB&ARG). Tertiary treatment processes are promising solutions, although the transitory inactivation of bacteria may select ARB&ARG. This study aimed at assessing the potential of ozonation and UV


Martins R.C.,CIEPQPF | Silva A.M.T.,Centro Empresarial e Tecnologico | Castro-Silva S.,Centro Empresarial e Tecnologico | Garcao-Nunes P.,Centro Empresarial e Tecnologico | Quinta-Ferreira R.M.,CIEPQPF
Environmental Technology | Year: 2011

Ozonation, catalytic ozonation, Fenton's and heterogeneous Fenton-like processes were investigated as possible pretreatments of a low biodegradable and highly toxic wastewater produced by a detergent industry. The presence of a Mn-Ce-O catalyst in ozonation enhances the biodegradability and improves the degradation at low pH values. However, a high content of carbonyl compounds adsorbed on the recovered solid indicates some limitations for real-scale application. A commercial Fe2O3-MnOx catalyst shows higher activity as well as higher stability concerning carbon adsorption, but the leaching of metals is larger than for Mn-Ce-O. Regarding the heterogeneous Fenton-like route with an Fe-Ce-O catalyst, even though a high activity and stability are attained, the intermediates are less biodegradable than the original compounds, indicating that the resulting effluent cannot be conducted to an activated sludge post-treatment. The highest enhancement of effluent biodegradability is obtained with the classic homogeneous Fenton's process, with the BOD5/COD ratio increasing from 0.32 to 0.80. This process was scaled up and the treated effluent is now safely directed to a municipal wastewater treatment plant. © 2011 Taylor & Francis.


Martins R.C.,University of Coimbra | Pinto F.L.,University of Coimbra | Castro-Silva S.,Centro Empresarial e Tecnologico | Quinta-Ferreira R.M.,University of Coimbra
Journal of Environmental Engineering (United States) | Year: 2013

This paper reports the application of flocculation, Fenton's process, and ozonation on the depuration of distillery wastewaters. The treatment processes were analyzed separately; nevertheless, integration schemes were also considered. The commercial flocculant 923PWG led to up to 84% of total suspended solids (TSS) removal even if a very low chemical oxygen demand (COD) abatement was observed (<2%). The effect of hydrogen peroxide concentration and [H2O2]/[Fe2+] molar ratio were tested on the Fenton's process efficiency. Moreover, the H2O2 injection mode was still analyzed. Gathering up both COD degradation and biodegradability enhancement, it was possible to select the following operating conditions: [H2O2]=0.5 M and [H2O2]/[Fe2+]=10 (mol/mol), being the oxidant totally introduced at the beginning of the reaction. Ozonation showed poor results regarding organic matter removal; however, it seems to be an interesting methodology raising the effluent's biochemical oxygen demand (BOD5)/COD ratio. In fact, in the strategies involving the integration of ozonation with Fenton's process, it was possible to conclude that ozone oxidation did not improve COD degradation; nonetheless, it was essential to improve biodegradability, particularly when conducting ozonation (at pH=3) after Fenton's process was revealed to be an interesting approach leading to an effluent amenable to further biodegradation. © 2013 American Society of Civil Engineers.


Amaral-Silva N.,University of Coimbra | Amaral-Silva N.,Centro Empresarial e Tecnologico | Martins R.C.,University of Coimbra | Castro-Silva S.,Centro Empresarial e Tecnologico | And 2 more authors.
Journal of Chemical Technology and Biotechnology | Year: 2016

BACKGROUND: The aim of this research was centered on the development of a suitable strategy for the treatment of a wastewater from the production of automotive coating pipes. RESULTS: Coagulation and Fenton treatments were ineffective and did not achieve the desired objectives, however, ozone based processes were shown to be an interesting technology. Several parameters affecting ozonation, such as pH, the addition of hydrogen peroxide as co-oxidant and the contact time, were optimized. It was concluded that the best efficiency was attained with ozone (2 g h−1) using a multi-stage pH procedure. After 1200 min reaction, this system achieved 98% chemical oxygen demand (COD) removal and the final effluent presented a BOD5/COD improvement from 0.11 to 0.30. CONCLUSION: This study proposes an effective method to treat this specific wastewater. Fenton oxidation enabled an increase in effluent biodegradability, however, not sufficient to enable a posterior biological treatment. Using ozonation, the operating conditions can be adapted to provide an effluent able to be discharged into the hydro resources (COD < 150 mgO2 L−1), or to be sent to the municipal sewage plant (COD < 1000 mgO2 L−1) where it will be further refined in a biological system. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry


Amaral-Silva N.,University of Coimbra | Martins R.C.,University of Coimbra | Castro-Silva S.,Centro Empresarial e Tecnologico | Quinta-Ferreira R.M.,University of Coimbra
Journal of Advanced Oxidation Technologies | Year: 2012

Water savings, reclamation and reuse in industry are topics of increasing economic interest due to water scarcity and costs. The search for an efficient and economical method to the depuration of two different effluents, namely from vegetable wash (VW) and chemical production (CP), was investigated by advanced oxidation processes as direct ozonation and O 3/H 2O 2 focusing in the evaluation of their effectiveness for decomposing COD and TOC aiming water reuse. The O 3/H 2O 2 combined system showed the highest oxidizing power amongst the two ozonation methodologies with stronger COD and TOC degradation degrees corresponding to 100% (0 mgO 2.L -1) and 33% (38 mgC.L -1) after 120 min for the VW and 96% (38 mgO 2.L -1) and 66% (62 mgC.L -1) for the CP after 180 minutes of oxidizing procedure. From the global analysis of the results it was possible to conclude that water reutilization is feasible when the perozonation process is applied fulfilling the environmental regulations. © 2012 Science & Technology Network, Inc.


Martins R.C.,University of Coimbra | Silva A.M.T.,Centro Empresarial e Tecnologico | Castro-Silva S.,Centro Empresarial e Tecnologico | Garcao-Nunes P.,Centro Empresarial e Tecnologico | Quinta-Ferreira R.M.,University of Coimbra
Environmental Technology | Year: 2010

In this experimental work the ozone action on the depuration of olive oil mill wastewater is studied for different operational conditions based on an actual industrial treatment plant. It was verified that the application of a Mn-Ce-O catalyst prepared at the laboratory, with a Mn/Ce molar proportion of 70/30, enhances the depuration efficiency and the effluent biodegradability. Ozonation operation at the natural pH of the effluent is recommended. Moreover, the integration of the Fenton process as a pretreatment improves the final chemical oxygen demand removal and enables a totally biodegradable effluent to be obtained, as confirmed by respirometric techniques. © 2010 Taylor & Francis.


PubMed | Centro Empresarial e Tecnologico and University of Coimbra
Type: Journal Article | Journal: Environmental technology | Year: 2016

The utilization of Fentons oxidation for the depuration of elderberry juice wastewater was studied. The aim was to select the adequate cost-effective operating conditions suitable to lead to an effluent within the legal thresholds to be discharged into the natural water courses. The treatment efficacy was assessed by chemical oxygen demand (COD), colour, phenolic content and total solids removal besides its ability to improve biodegradability (biochemical oxygen demand (BOD5)/COD). Moreover, the costs of the applied reactants were also considered. Fentons reaction was able to abate at least 70% of COD (corresponding to a final value below 150mg O2L(-1)). Besides, total phenolic content degradation was always achieved. Within these conditions, the resulting effluent is able to be directly discharged into the natural hydric channels. Fenton oxidation could be successfully applied as a single treatment method with a reactant cost of 4.38m(-3) ([Fe(2+)]=20mmolL(-1), [H2O2]=100mmolL(-1), pH=3 and 4h of oxidation procedure).


Amaral-Silva N.,University of Coimbra | Amaral-Silva N.,Centro Empresarial e Tecnologico | Martins R.C.,University of Coimbra | Castro-Silva S.,Centro Empresarial e Tecnologico | Quinta-Ferreira R.M.,University of Coimbra
Environmental Technology (United Kingdom) | Year: 2016

A complete industrial treatment system (involving the integration of coagulation/flocculation and Fenton processes) to depurate real wastewaters coming from two-phase olive oil production mills has been studied. The experimental results indicated that at the end of this combined strategy, involving a primary physical separation stage followed by Fenton's chemical oxidation, chemical oxygen demand (COD) is reduced up to 90% and total polyphenols' concentration is decreased up to 92%. The treated stream biodegradability (BOD5/COD) reached 0.52 and the Total Suspended Solids (TSSs) and Total Dissolved Solids (TDSs) decreased up to 95% and 69%, respectively. Fenton's procedure was optimized bearing in mind the pH adjustment step, different procedures for hydrogen peroxide addition and the use of coagulants instead of the chemical precipitation (by raising pH) to promote iron sludge settling. Our results demonstrated that pH (3.0 ± 0.1) control during the oxidation reaction improves the oxidation efficiency. Moreover, the final NaOH addition is essential to a better sludge formation and consequent precipitation of the residual iron removing also some organic matter. © 2016 Taylor & Francis


Martins R.C.,University of Coimbra | Jimenez B.M.,University of Coimbra | Castro-Silva S.,Centro Empresarial e Tecnologico | Quinta-Ferreira R.M.,University of Coimbra
Ozone: Science and Engineering | Year: 2012

This article explores the application of several ozone-based technologies on the abatement of a bio-refractory stream coming from an elderberry juice plant (BOD5/COD = 0.26). The impact of ozone inlet concentration and pH was addressed firstly, followed by the analysis of the O3+H2O2 combined system. Finally, the activity and stability of two solid catalysts (Mn-Ce-O and Fe-Mn-O) was assessed. None of the approaches produced values within the legal thresholds for direct discharge into water-courses. It is advisable to integrate the chemical treatment with a bio-reactor. Thus, single ozonation at pH = 3 (BOD5/COD = 0.48), O3+[H2O2] = 32.5 mM (BOD5/COD = 0.46) and O3+Mn-Ce-O at pH = 3 (BOD5/COD = 0.44) are promising strategies. © 2012 Copyright 2012 International Ozone Association.


Hormigo T.,Centro Empresarial e Tecnologico | Araujo J.,Centro Empresarial e Tecnologico
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2013

Spin. Works has developed a complete micro-UAV system with the purpose of supporting forest management activities. The aircraft is based on a winged-body design spanning 1.8m with a maximum take-off weight of 2kg, and can carry out missions lasting up to 2h at a cruise speed of about 60km/h. The corresponding ground station ensures the mission planning functions, real-time flight monitoring and visualization, and serves also as a real-time and post-flight data exploitation platform. A particular emphasis is placed on image processing techniques applied to two operational concepts: a fire detection service and a forest mapping service. The real-time operations related to fire detection consist on object tracking and geo-referencing functions, which can be operated by a user directly over the video stream, enabling the quick estimation of the 3D location (latitude, longitude, altitude) of suspected fires. The post-flight processing consists of extracting valuable knowledge from the payload data, in particular tree coverage maps, orthophoto mosaics and Digital Surface Models (DSMs), which can be used for further forest characterization such as wood and cork volume estimation. The system is currently entering initial operations, with expanded operations expected during Q3 2013.

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