Yes / N-nitrosamine in wastewater treatment processes can contribute to several public health impacts including human carcinogens even at very low concentration. In this work, spiral-wound reverse osmosis (SWRO) process is used to remove N-nitrosamine compounds from wastewater. Effects of operating parameters of the SWRO process on the removal of N-nitrosamine, total water recovery, and specific energy consumption for a SWRO configurations are evaluated via simulation and optimisation. For this purpose, the one-dimensional distributed model developed earlier by the authors is modified by including different mass transfer coefficient correlation, temperature dependent water and solute permeability correlations and energy equations. The model is first validated by estimating a new set of model parameters using eight set of experimental data from the literature and is then used to simulate the process with and without energy recovery device to facilitate deeper insight of the effect of operating conditions on the process performance. The model is then embedded within an optimisation framework and optimisation problems to maximise N-nitrosamine rejections and to minimise specific energy consumption are formulated and solved while the operating conditions are optimized simultaneously.

Yes / Phenol and phenolic derivatives found in different industrial effluents are highly toxic and extremely harmful to human and the aquatic ecosystem. In the past, trickle bed reactor (TBR), reverse osmosis (RO) and other processes have been used to remove phenol from wastewater. However, each of these technologies has limitations in terms of the phenol concentration in the feed water and the efficiency of phenol rejection rate. In this work, an integrated hybrid TBR-RO process for removing high concentration phenol from wastewater is suggested and model-based simulation of the process is presented to evaluate the performance of the process. The models for both TBR and RO processes were independently validated against experimental data from the literature before coupling together to make the hybrid process. The results clearly show that the combined process significantly improves the rejection rate of phenol compared to that obtained via the individual processes.

Yes / Reverse Osmosis (RO) processes are readily used for removing pollutants, such as dimethylphenol from wastewater. A number of operating parameters must be controlled within the process constraints to achieve an efficient removal of such pollutants. Understanding the process dynamics is absolutely essential and is a pre-step for designing any effective controllers for any process. In this work, a detailed distributed two-dimensional dynamic (x and y dimensions and time) model for a spiral-wound RO process is developed extending the 2-D steady state model of the authors published earlier. The model is used to capture the dynamics of the RO process for the removal of dimethylphenol from wastewater. The performance of the 2-D model is compared with that obtained using 1-D dynamic model before the model is being used to investigate the performance of the RO process for a range of operating conditions.

Yes / Reverse osmosis (RO)is one of the most important technologies used in wastewater treatment plants due to high contaminant rejection and low utilization of energy in comparison to other treatment procedures. For single-component spiral-wound reverse osmosis membrane process, one dimensional steady state and dynamic mathematical models have been developed based on the solution-diffusion model coupled with the concentration polarization mechanism. The model has been validated against reported data for wastewater treatment from literature at steady state conditions. Detailed simulation using the dynamic model has been carried out in order to gain deeper insight of the process. The effect of feed flow rate, pressure, temperature and concentration of pollutants on the performance of the process measured in terms of salt rejection, recovery ratio and permeate flux has been investigated.

Submitted by Eunice Novais (enovais@uepg.br) on 2018-06-26T19:10:46Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Ana Carolina M. Rodrigues.pdf: 2130324 bytes, checksum: 0340ff571493224c3f33ecd693bb1e77 (MD5) / Made available in DSpace on 2018-06-26T19:10:46Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Ana Carolina M. Rodrigues.pdf: 2130324 bytes, checksum: 0340ff571493224c3f33ecd693bb1e77 (MD5) Previous issue date: 2018-04-12 / Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná / A má distribuição de água doce no mundo, o crescimento populacional acentuado, as mudanças climáticas e as consequências das ações antropológicas traz a necessidade da busca de fontes alternativas para suprir a demanda de água aos seres humanos, animais e plantas. A abundância de água salgada ou salobra é muitas vezes, a única fonte de água disponível para sobrevivência de algumas comunidades no planeta, isso tem impulsionado o uso de técnicas de dessalinização. Com o objetivo de estudar alternativas para adaptações climáticas, antecipar tendências e problemas hídricos futuros foi implantado um sistema de dessalinização de água salobra, em escala piloto, nas dependências da Estação de Tratamento de Água (ETA) da Sanepar, em Praia de Leste, no município de Pontal do Paraná no litoral do estado. O sistema piloto foi provido de ultrafiltração (UF) como pré-tratamento seguido de abrandamento e da dessalinização por osmose reversa (OR). Com capacidade para produzir 1 m3.h-1 de água tratada. A água salobra foi padronizada nas concentrações de 1000 ± 50 mg.L-1 e 1500 ± 20 mg.L-1 de sólidos dissolvidos totais (SDT), por meio da mistura da água do mar e da água bruta do Rio das Pombas, manancial que abastece o balneário. Avaliou-se o sistema global a partir de dados de produção e consumo de água, balanço de massa e das taxas de recuperação para configurações diferentes do sistema de OR. Para isso, foram realizados quatro experimentos, variando a configuração de abertura do registro do concentrado da OR: o primeiro com abertura de 72,71% de concentrado (A); o segundo 59,20 % (B); o terceiro 39,70% (C), estes com 1500 ± 20 mg.L-1 de SDT; o quarto experimento foi realizado para 1000 ± 50 mg.L-1 de SDT com abertura de 32,90% de concentrado (D). Aproximadamente 15% do volume de alimentação era utilizado na limpeza hidráulica das membranas da UF e da OR. Quanto maiores as vazões do concentrado da OR, maior a vazão de alimentação, e consequentemente, menor a taxa de recuperação e pressão osmótica. A maior taxa de recuperação obtida foi de 69,13% para o experimento D, sendo considerada a configuração mais otimizada. / With the unequal distribution of fresh water in the world, strong population growth, climate change and the consequences of anthropological actions it is necessary to look for alternative sources to supply the water demand for human beings, animals and plants. Salt water or brackish water has been the only source of water available for survival in some communities on the planet. This issue has driven the use of desalination techniques. With the objective of studying alternatives for climate adaptation, anticipating of trends and problems and water problems, a brackish water desalination system in pilot scale was implemented on the premises of the Water Treatment Plant Station, in Praia de Leste, in the Pontal do Paraná City, coast of the State. The pilot system was provided with ultrafiltration (UF) as a pretreatment followed by softening and reverse osmosis (RO), with the capacity to produce 1m3.h-1 of permeate. Brackish water was produced at concentrations of 1,000 ± 50 mg.L-1 and 1,500 ± 20 mg.L-1 of total dissolved solids (TDS), by mixing sea water and fresh water from the Pombas River, which supplies the town. The global system was evaluated from production and water consumption data, mass balance and recovery rates for different configurations of the reverse osmosis system. For this, four experiments were performed, varying the configuration of the valve which controls the flow of the brine: the first one with 72.71% (A); the second with 59.20%(B); the third with 39.70% (C), these with 1,500 ± 20 mg.L-1 of TDS; the fourth experiment was also performed for 1,000 ± 50 mg.L-1 of TDS with 32.90% of the brine (D). About 15% of volume of water produced was used in the hydraulic cleaning of the UF and RO membranes. When the flow rates of the concentrate were higher, the feed rates were also higher and consequently, the recovery rates and osmotic pressure were lower. The highest recovery rate was 69.13% for the experiment D, being considered the most optimized configuration.

Vienu iš pagrindiniu geologinės aplinkos teršėju yra laikomi sąvartynai. Todėl daugelyje šalių jie yra inventorizuojami ir tiriami, prognozuojamas jų poveikis gamtinei aplinkai. Lietuvai sąvartynų poveikio aplinkai problema taip pat labai aktuali. Todėl imtasi konkrečių priemonių informacijos apie sąvartynus kaupimui ir jų taršos mąsto įvertinimo. Tuo tikslu buvo atliekama ir iki šiol tebevykdoma sąvartynų inventorizacija. Kai kuriuose sąvartynuose buvo vykdomi įvairaus detalumo geologiniai-hidrogeologiniai tyrimai. Šiame darbe analizuojama Jerubaičių sąvartyno filtrato dinamika. Pateikiama sąvartyne susikaupusio filtrato judėjimo schema. Bei jo valymas atvirkštinės osmozės būdu. Tiriamas filtrato kiekio kitimas keičiantis meteorologinėm sąlygom, analizuojamas laikotarpis nuo 2008.05.15 iki 2008.12.31. Tiriamas laikotarpis, nuo gegužės 15 iki sausio 1, apima visus metų laikus bei atspindi tipines Lietuvos meteorologinės sąlygos. Darbe tiriama filtrato susidarymo priklausomybė sąvartyne nuo atvežamų šiukšlių kiekio ir meteorologinių sąlygų. Duomenys pateikiami grafiškai juos apdorojus, duomenų statistiniam apdorojimui panaudota programa STATISTICA. / Landfill is considered as one of the main geo-environmental polluters. Therefore, in most countries they are inventoried, analyzed and forecast their impact for the natural environment. Lithuania landfill’s environmental problem is also relevant. Consequently, there are taken appropriate actions about landfills and their accumulation of pollution assessment. This was done and it is still ongoing landfill inventory. In some landfills there were carried out a wide range of detail geological-hydrogeological researches. This document analyzes Jėrubaičiai landfill leachate dynamics. There is available landfill leachate accumulated movement scheme and its cleaning by reverse osmosis method. This analysis shows leachate flow dynamics in different meteorological conditions. Research period was from 2008.05.15 to 2008.12.31. Selected research period is covering all seasons and represents Lithuanian meteorological conditions. In this document explored formation of leachate dependency from incoming garbage amount and weather conditions. Research data are represented graphically; program STATISTICA was used for statistical data processing.

An accurate model for RO process has significant importance in the simulation and optimization proposes. A steady state model of RO process is developed based on solution diffusion theory to describe the permeation through membrane and thin film approach is used to describe the concentration polarization. The model is validated against the operation data reported in the literature. For the sake of clear understanding of the interaction of feed temperature and salinity on the design and operation of RO based desalination systems, simultaneous optimization of design and operation of RO network is investigated based on two-stage RO superstructure via MINLP approach. Different cases with several feed concentrations and seasonal variation of seawater temperature are presented. Also, the possibility of flexible scheduling in terms of the number of membrane modules required in operation in high and low temperature seasons is investigated A simultaneous modelling and optimization method for RO system including boron removal is then presented. A superstructure of the RO network is developed based on double pass RO network (two-stage seawater pass and one-stage brackish water pass). The MINLP problem based on the superstructure is used to find out an optimal RO network which will minimize the total annualized cost while fulfilling a given boron content limit. The effect of pH on boron rejection is investigated at deferent seawater temperatures. The optimal operation policy of RO system is then studied in this work considering variations in freshwater demand and with changing seawater temperature throughout the day. A storage tank is added to the RO layout to provide additional operational flexibility and to ensure the availability of freshwater at all times. Two optimization problems are solved incorporating two seawater temperature profiles, representing summer and winter seasons. The possibility of flexible scheduling of cleaning and maintenance of membrane modules is investigated. Then, the optimal design and operation of RO process is studied in the presence of membrane fouling and including several operational variations such as variable seawater temperature. The cleaning schedule of single stage RO process is formulated as MINLP problem using spiral wound modules. NNs based correlation has been developed based on the actual fouling data which can be used for estimating the permeability decline factors. The correlation based on actual data to predict the annual seawater temperature profile is also incorporated in the model. The proposed optimization procedure identified simultaneously the optimal maintenance schedule of RO network including its design parameters and operating policy. The steady state model of RO process is used to study the sensitivity of different operating and design parameters on the plant performance. A non-linear optimization problem is formulated to minimize specific energy consumption at fixed product flow rate and quality while optimizing the design and operating parameters. Then the MINLP formulation is used to find the optimal designs of RO layout for brackish water desalination. A variable fouling profile along the membrane stages is introduced to see how the network design and operation of the RO system are to be adjusted Finally, a preliminary control strategy for RO process is developed based on PID control algorithm and a first order transfer function (presented in the Appendix).

This paper presents the results of the spike tests performed in the alternative water supply pilot testing program for the City of Pembroke Pines. It establishes the effectiveness of a protocol that can be used to gain further insight on the rejection capacities of RO membranes. An in-depth study of the molecular descriptors affecting rejection by RO membranes is presented and used in the development of a discriminant function analysis. This analysis proved to be an effective way to predict the passage of Emerging Substances of Concern (ESOCs) through RO membrane. Further, a principal component (PC) analysis was performed to determine which factors accounted the largest variation in RO permeability. Additionally, this paper defines the groundwork for a discriminant analysis model that, if further developed, could serve as an important tool to predict the rejection capabilities of RO treatment when handling with ESOCs. / by Fernando J. Pleitez Herrera. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

Sistemas de membranas filtrantes, principalmente os de osmose reversa, estão sendo cada vez mais utilizados em diversos seguimentos de empresas (farmacêutica, tratamento de água, alimentícia e química), devido à diminuição do preço dos elementos filtrantes e da alta qualidade do produto obtido. Apesar do preço dos elementos de osmose reversa terem caído nos últimos tempos, a substituição destes continua sendo o fator mais dispendioso de um sistema de osmose reversa. A autópsia de membranas é uma técnica utilizada para investigar a causa que levou à colmatação de um elemento, contribuindo no melhoramento do pré-tratamento da água de alimentação e consequentemente aumentando a vida útil dos elementos. O presente trabalho teve como objetivo incrementar a técnica de autópsia de membranas de osmose reversa através da análise da volatilização dos principais compostos inorgânicos presentes nestas membranas, modificação na metodologia de quantificação de açúcares e proteínas, comparação de diferentes técnicas de remoção do material depositado sobre as membranas e análise da distribuição de biofilmes sobre elementos colmatados de osmose reversa. A análise dos resultados mostrou que dentre os inorgânicos, ocorreu volatilização completa do cloreto de amônio e pequena variação no composto cloreto férrico; a quantificação de proteínas e açúcares, através da fortificação das amostras, apresentou valores diferentes quando comparados com os valores obtidos diretamente da curva padrão, devido à diferença de inclinação entre as retas de fortificação e padrão; os resultados também mostraram que a trituração foi mais eficiente na remoção do material aderido quando comparado com a raspagem e a sonicação e a distribuição de biofilmes se mostrou uniforme nos dois elementos analisados. / Filter membrane systems, especially reverse osmosis, are being increasingly used in various business segments (pharmaceutical, water treatment, food and chemical) due to decrease in the price of the filter elements and high quality product. Although the price of reverse osmosis elements have fallen in recent times, the replacement of the part remains more expensive a reverse osmosis system. The autopsy of membranes is a technique used to investigate the cause that led to clogging of one factor contributing to the improvement of pre-treatment of water feeding and consequently increasing the life of the elements. This study aimed to improve the technique of autopsy reverse osmosis membranes by examining the volatilization of major inorganic compounds present in these membranes, modification the methodology for quantification of sugars and proteins, comparison of different techniques for removal of material deposited on the membranes and distribution analysis of biofilms on elements obscured reverse osmosis. The results showed that among the Inorganic volatilization was full of ammonium chloride and small variation in the compound ferric chloride, the quantification of proteins and sugars, by fortifying the samples showed different values when compared with values obtained directly the standard curve due to the difference in slope between the lines of and fortification standard, the results also showed that the blending was more efficient in removing adhered material when compared with the scraping and sonication and distribution of biofilms showed uniform the two elements analyzed.

A água exerce papel fundamental nas diferentes fases do processo de fabricação de artigos para saúde (médico-hospitalares, farmacêuticos, e clínicos), exigindo elevado grau de pureza, que certifique a sua inocuidade. Portanto, se faz necessário maior controle dos sistemas de purificação de água e suas etapas de tratamento, onde a formação de biofilmes pode contaminar os artigos para saúde e, consequentemente, causar injúria a pacientes submetidos à aplicação dos mesmos. Embora os artigos médicos sejam esterilizados por óxido de etileno (ETO), seu processo de manufatura deve prever o mínimo acréscimo possível de contaminantes. Considerando que a água purificada e a esterilização dos artigos para saúde são fatores determinantes para o sucesso de sua aplicação, este trabalho foi dividido em duas partes distintas. A primeira parte aborda o controle das etapas de purificação da água, que é destinada à lavagem de componentes termoplásticos, que são utilizados na fabricação de artigos para saúde. Os níveis máximos de carga microbiana (expressos em ciclos de log10 UFC/100mL) encontrados ao longo do sistema de purificação de água foram: 3,48 log10 na água de entrada; 3,57 log10 nos filtros multimeios; 3,75 log10 nos abrandadores; 4,97 log10 no filtro de carvão ativado; 2,53 log10 na osmose reversa; 2,70 log10 no tanque de estocagem e distribuição; 2,56 log10 na lâmpada ultravioleta; 2,53 log10 nos filtros 0,05 µm; 1,98 log10 nos pontos de uso. Flavimonas oryzihabitans e Micrococcus luteus foram as bactérias Gram-negativa e Grampositiva, respectivamente, isoladas e identificadas com maior freqüência na água, em diferentes estágios do sistema, inclusive após a passagem dessa através das membranas de osmose reversa. A segunda parte do estudo teve como objetivo determinar o tempo de aeração necessário para que os oxigenadores de sangue e conjuntos de tubos de PVC, após esterilização por ETO, permaneçam em aeração, para dissipação dos resíduos de ETO. Avaliou-se também a potencialidade da proteína verde fluorescente (GFP) como biossensor no processo de esterilização. O processo de esterilização destes artigos médicos foi monitorado com indicadores biológicos Bacillus atrophaeus, proteína verde fluorescente (GFP) e controles de temperatura, pressão e umidade em ciclos de 2 h (ciclo curto), 4 h (meio ciclo) e 8 h (ciclo longo). As curvas de dissipação, determinadas por cromatografia gasosa, confirmaram níveis residuais menores que 25 ppm para ETO e etileno cloridrina (EC); e inferiores a 250 ppm para etileno glicol (EG), ao final do processo de esterilização para os oxigenadores; e, após 221 horas de aeração, para os conjuntos de tubos de PVC. Nos ciclos de esterilização, as reduções na intensidade de fluorescência da GFP ocorreram em função do tempo de exposição ao ETO; enquanto germinação de esporos e/ou crescimento de B. atrophaeus não foi observado. / The water exerts important paper in different phases of critical items manufacture in the health care units, pharmaceutical industries, hospitals and clinics, becoming necessary a rigorous control of the water purification systems, storage and distribution, in order to prevent biofilms formation and cross-contamination between devices and patients, who are submitted to critical articles and parenteral solution application. The sterilization of critical devices by ethylene oxide (ETO) should predict minimum addition of possible contaminants and residues. Considering that the purified water and the sterilization are crucial factors for medical devices, this work was divided in two parts. The first part evaluated continuously the stages of the system for the purification of the water, which purity level is critical and determines the quality of the washing of thermoplastic components used in the manufacture of critical items. The maximum levels of heterotrophic load (log10 UFC/100mL) found throughout the water purification system were: 3.48 log10 in the water inlet; 3.57 log10 in the multimedium filters; 3.75 log10 in the softeners; 4.97 log10 in the activated carbon filter; 2.53 log10 in the reverse osmosis; 2.70 log10 in the tank of storage and distribution; 2.56 log10 in the UV lamp; 2.53 log10 in the 0.05µm filters; 1.98 log10 in the consumption points. Flavimonas oryzihabitans and Micrococcus luteus were the main Gram-negative and Grampositive bacteria, respectively found in the purified water after reverse osmosis. The second part of this study had as objective the determination of the needed aeration time for blood oxygenators and sets of PVC tubing must be kept in aeration room for dissipation of ETO residues; and also evaluated the possibility of GFP as biosensor. ETO is used as in a mixture (10% ETO and 90% CO2). Residual levels of ETO and its derivatives, ethylene chloridrin (ECH) and ethylene glycol (EG), which remain in these devices, must be controlled to prevent serious injuries to the patients. The sterilization process of the oxygenators and sets of PVC tubing was monitored with Bacillus atrophaeus and fluorescent green protein (GFP). The temperature, pressure and humidity were controlled in the sterilization cycles of 2 h (short cycle), 4 h (half cycle) and 8 h (long cycle). The dissipation curves of the residues were determined by gaseous chromatography and the residual concentrations were lower than 25 ppm of ETO and ECH and lower than 250 ppm of EG immediately after the sterilization processes for oxygenators and after 221 hours of aeration for the sets of PVC tubing. Reductions in the fluorescence intensity of GFP were observed as a function of the exposition time to the ETO. No growth of B. atrophaeus spores was observed after cycles.