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Nutrient removal from an anaerobic membrane bioreactor effluent using microalgae. Study and modeling of the processRuiz Martínez, Ana 07 January 2016 (has links)
Tesis por compendio / [EN] Anaerobic membrane bioreactors for urban wastewater treatment present interesting advantages when compared with aerobic treatments, such as less sludge production, lower energy demand and biogas generation. However, the generated effluent cannot generally be discharged without further ammonium and phosphate elimination. This thesis studies the removal of these inorganic nutrients by means of microalgae cultivation.
The main objective of this work is therefore to obtain an autochthonous microalgal culture and to investigate its ability to grow on an already existing anaerobic effluent, as well as to research the extent to which ammonium and phosphate can be removed. Moreover, this thesis aims at providing the kinetic expressions which reproduce the main processes involved, in order to provide the basis for process simulation and design.
Microalgae were isolated from a local wastewater treatment plant and their ability to grow on the anaerobic effluent -while successfully removing ammonium and phosphate- was demonstrated. An excellent water quality was obtained with a semicontinuous cultivation mode under constant illumination. The Scenedesmus and Chlorococcum genus proliferated more efficiently and thus became predominant in the culture. Results also showed that phosphorus was the limiting nutrient in the anaerobic effluent to be treated. The influence of phosphorus limitation on ammonium and phosphate removal, as well as the influence of temperature in ammonium removal, were then studied under laboratory conditions. Kinetic expressions which reproduce the observed effects were proposed and validated, taking also into account the effect of light intensity. Additionally, a Scenedesmus-dominated culture was grown under varying light and temperature in an outdoor flat-plate photobioreactor, with constant monitoring of light intensity, temperature and ammonium concentration. Acceptable results were obtained in the reproduction of the experimental data, albeit with less accuracy than under laboratory conditions.
The work here presented demonstrates the feasibility of coupling a microalgal cultivation system to an anaerobic membrane bioreactor for urban wastewater treatment. The basic factors affecting microalgal nutrient removal are researched, and mathematical models are provided which reproduce these effects.
This Ph.D. thesis is enclosed in a national research project funded by the Spanish Ministry of Economy and Competitiveness entitled "Estudio experimental de la recuperación como biogás de la energía de la materia orgánica y nutrientes del agua residual, acoplando un AnBRM y un cultivo de microalgas" (MINECO project CTM2011-28595-C02-01/02). This research was also supported by the Spanish Ministry of Education, Culture and Sport via a pre doctoral FPU fellowship to the author (AP2009-4903) / [ES] En el tratamiento de aguas residuales urbanas, los bioreactores anaerobios de membranas presentan ventajas interesantes frente a los tratamientos aerobios. Algunas de estas ventajas son la menor producción de fangos, un menor consumo energético y la producción de biogás. Sin embargo, y generalmente, el efluente obtenido no puede ser vertido al medio sin una etapa previa de eliminación de amonio y fosfato. La presente tesis estudia la eliminación de dichos nutrientes inorgánicos empleando para ello un cultivo de microalgas.
El objetivo principal de este trabajo es, por tanto, la obtención de un cultivo autóctono de microalgas y la evaluación de la capacidad que éstas tienen tanto de crecer en un efluente anaerobio como de eliminar el amonio y el fosfato presentes. Asimismo, se pretenden proporcionar las bases para la simulación y el diseño del sistema de depuración propuesto, mediante la obtención de las expresiones cinéticas que reproducen los principales procesos involucrados.
En primer lugar se ha demostrado la capacidad de las microalgas, aisladas en una estación depuradora de aguas residuales, de crecer en el efluente anaerobio y de eliminar con éxito el amonio y fosfato en éste presente. El agua tratada, obtenida a mediante un proceso semicontinuo y con iluminación constante, presenta una excelente calidad. Los géneros Scenedesmus y Chlorococcum han proliferado más eficientemente y han llegado a ser los predominantes en el cultivo. Los resultados obtenidos indican que el nutriente limitante en el efluente a tratar es el fósforo, y por tanto la influencia de la limitación de fósforo en la eliminación de nutrientes ha sido estudiada en condiciones de laboratorio, junto con la influencia de la temperatura en la velocidad de eliminación de amonio. Han sido propuestas y validadas las correspondientes expresiones cinéticas que reproducen los efectos observados, teniendo en cuenta en todo momento la influencia de la intensidad de la luz.
Por otro lado, un cultivo de Scenedesmus ha sido cultivado en el exterior, bajo condiciones cambiantes de luz y temperatura, que a su vez han sido monitorizadas constantemente, junto con la concentración de amonio. Los datos obtenidos han sido reproducidos mediante modelación matemática con resultados aceptables, aunque la precisión obtenida es menor que en condiciones de laboratorio.
La presente tesis demuestra la viabilidad de combinar un cultivo de microalgas con un bioreactor de membranas para el tratamiento de agua residual urbana. Se exponen asimismo los factores básicos que influyen en la velocidad de eliminación de nutrientes, y se presentan los modelos matemáticos necesarios para reproducir los efectos observados.
La presente tesis doctoral se incluye en el marco de un proyecto nacional de investigación financiado por el Ministerio de Economía y Competitividad de título "Estudio experimental de la recuperación como biogás de la energía de la materia orgánica y nutrientes del agua residual, acoplando un AnBRM y un cultivo de microalgas" (CTM2011-28595-C02-01/02). La presente tesis doctoral ha sido también financiada por el Ministerio de Educación, Cultura y Deporte a través de una ayuda para contratos predoctorales de Formación del Profesorado Universitario (AP2009-4903). / [CA] En el tractament d'aigües residuals urbanes, els bioreactors anaerobis de membrana tenen avantatges interessants respecte als tractaments aerobis. Alguns d'aquests avantatges són: menys producció de fangs, menys consum energètic i la producció de biogàs. No obstant això, i en general, l'efluent obtingut no es pot tornar al medi sense una etapa prèvia d'eliminació d'amoni i fosfat. Aquesta tesi estudia l'eliminació d'aquests nutrients inorgànics emprant per a fer-ho un cultiu de microalgues.
L'objectiu principal d'aquest treball és, per tant, l'obtenció d'un cultiu autòcton de microalgues i l'avaluació de la capacitat que aquestes tenen tant de créixer en un efluent anaerobi com d'eliminar l'amoni i el fosfat presents. Així mateix, volem proporcionar les bases per a la simulació i el disseny del sistema de depuració proposat, mitjançant l'obtenció de les expressions cinètiques que reprodueixen els principals processos involucrats.
En primer lloc, s'ha demostrat la capacitat de les microalgues, aïllades en una estació depuradora d'aigües residuals, de créixer en l'efluent anaerobi i d'eliminar amb èxit l'amoni i el fosfat presents. L'aigua tractada, obtinguda mitjançant un procés semicontinu i amb il·luminació constant, presenta una qualitat excel·lent. Els gèneres Scenedesmus i Chlorococcum han proliferat més eficientment i han arribat a ser els predominants en el cultiu. Els resultats obtinguts indiquen que el nutrient limitant en l'efluent per tractar és el fòsfor, i per tant la influència de la limitació de fòsfor en l'eliminació tant d'amoni com de fosfat ha sigut estudiada en condicions de laboratori, juntament amb la influència de la temperatura en la velocitat d'eliminació d'amoni. S'han proposat i validat les expressions cinètiques corresponents que reprodueixen els efectes observats, tenint en compte en tot moment la influència de la intensitat de la llum.
D'altra banda, s'ha cultivat a l'exterior un cultiu predominat per Scenedesmus, sota condicions canviants de llum i temperatura, que al seu torn s'han monitorat constantment, juntament amb la concentració d'amoni. Les dades obtingudes s'han reproduït mitjançant simulació matemàtica amb resultats acceptables, encara que la precisió obtinguda és més baixa que en condicions de laboratori.
La nostra tesi demostra la viabilitat de combinar un cultiu de microalgues amb un bioreactor de membrana per al tractament d'aigua residual urbana. La tesi exposa així mateix els factors bàsics que influeixen en la velocitat d'eliminació de nutrients, i presenta els models matemàtics necessaris per a reproduir els efectes observats.
Aquesta tesi doctoral s'inclou en el marc d'un projecte nacional de recerca finançat pel Ministeri d'Economia i Competitivitat amb el títol "Estudio experimental de la recuperación como biogás de la energía de la materia orgánica y nutrientes del agua residual, acoplando un AnBRM y un cultivo de microalgas" (CTM2011-28595-C02-01/02). La tesi doctoral ha sigut també finançada pel Ministeri d'Educació, Cultura i Esport a través d'una ajuda per a contractes predoctorals de formació del professorat universitari (AP2009-4903). / Ruiz Martínez, A. (2015). Nutrient removal from an anaerobic membrane bioreactor effluent using microalgae. Study and modeling of the process [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59409 / Compendio
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Ethanol amine functionalized electrospun nanofibers membrane for the treatment of dyes polluted wastewaterAlAbduljabbar, Fahad A., Haider, S., Alghyamah, A., Haider, A., Khan, R., Almasry, W.A., Patel, Rajnikant, Mujtaba, Iqbal, Ali, F.A.A. 25 March 2022 (has links)
Yes / This study investigated adsorption kinetics, adsorption equilibrium, and adsorption isotherm of three dyes [i.e., methylene blue (MB), rhodamine-B (RB), and safranin T (ST)] onto polyacrylonitrile (PAN) and ethanolamine (EA) grafted PAN nanofibers (NFs) membranes (EA-g-PAN). The membranes were characterized by field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR) spectroscopy, and Brunauer–Emmet–Teller (BET). FE-SEM showed a smooth morphology for the NFs before and after grafting, while FT-IR confirmed EA grafting into the nitrile group of PAN. The grafting percentage with no change in the physical nature of the membrane was 12.18%. The nitrogen adsorption–desorption isotherms for PAN and EA-g-PAN NFs membranes were similar and classified as a Type IV according to the International Union of Pure and Applied Chemistry. The surface area, pore-volume, and pore size of the EA-g-PAN increased to 21.36 m2 g−1, 0.16 cm3 g−1, and 304.93 Å, respectively. The pores were cylindrical mesopores with bimodal openings, which means that pores were open at both ends. The adsorption of the MB, RB, and ST dyes onto the PAN and EA-g-PAN NFs membranes leveled off at ~ 60 min. The adsorption kinetics showed good fitting to pseudo-second-order kinetic model and multi-step diffusion process. The order of the dye adsorption was PAN / the Deanship of Scientific Research, King Saud University [RG-1440-060]
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Resource Recovery By Osmotic Bioelectrochemical Systems Towards Sustainable Wastewater TreatmentQin, Mohan 14 November 2017 (has links)
Recovering valuable resources from wastewater will transform wastewater management from a treatment focused to sustainability focused strategy, and creates the need for new technology development. An innovative treatment concept - osmotic bioelectrochemical system (OsBES), which is based on cooperation between bioelectrochemical systems (BES) and forward osmosis (FO), has been introduced and studied in the past few years. An OsBES can accomplish simultaneous treatment of wastewater and recovery of resources such as nutrient, energy, and water (NEW). The cooperation can be accomplished in either an internal (osmotic microbial fuel cells, OsMFC) or external (microbial electrolysis cell-forward osmosis system, MEC-FO) configuration. In OsMFC, higher current generation than regular microbial fuel cell (MFC) was observed, resulting from the lower resistance of FO membrane. The electricity generation in OsMFC could greatly inhibit the reverse salt flux. Besides, ammonium removal was successfully demonstrated in OsMFC, making OsMFCs a promising technology for "NEW recovery" (NEW: nutrient, energy and water). For the external configuration of OsBES, an MEC-FO system was developed. The MEC produced an ammonium bicarbonate draw solute via recovering ammonia from synthetic organic solution, which was then applied in the FO for extracting water from the MEC anode effluent. The system has been advanced with treating landfill leachate. A mathematical model developed for ammonia removal/recovery in BES quantitatively confirmed that the NH4+ ions serve as effective proton shuttles across cation exchange membrane (CEM). / Ph. D. / Nowadays, wastewater is no longer considered as waste. Instead, it is a pool for different kinds of resources, such as nutrient, energy, and water (NEW). Various technologies were developed to achieve NEW recovery from wastewater. A novel concept, osmotic bioelectrochemical system (OsBES) has been introduced and studied in the past few years. OsBES is based on two technologies: bioelectrochemical systems (BES) and forward osmosis (FO); and the corporation between these two technologies could accomplish simultaneous wastewater treatment and resource recovery. We investigated two kinds of OsBES: one is osmotic microbial fuel cells (OsMFC), and the other is microbial electrolysis cell-forward osmosis system (MEC-FO). For OsMFC, a mathematical model was built to understand the internal resistance, which will affect the current generation according to Om’s law (I=U/R). The salt transport across the cation exchange membrane (CEM) is related to the current generation. The ion transport, especially ammonium/ammonia transport, across CEM membrane in BES was modelled, which will help the BES design and operation for ammonia recovery systems. The system performance for wastewater treatment and resource recovery in MEC-FO was fully investigated with both synthetic wastewater and landfill leachate. The results indicated that MEC-FO is a promising system for NEW recovery.
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The Mechanisms, Products, and Kinetic of Carbamazepine-Free Chlorine ReactionsKotcharaksa, Komgrit 22 January 2009 (has links)
Carbamazepine (CBZ) is an antiepileptic drug widely detected in drinking water supplies and wastewater effluent. It has been previously found that CBZ is recalcitrant to biological removal processes. Therefore, active CBZ will be exposed to wastewater effluent disinfection processes, which for most treatment plants in the United States involves the addition of free chlorine. However, the chlorination mechanisms of CBZ have not been fully investigated and are currently poorly understood. Our experimental studies were conducted to examine the chlorination of CBZ under controlled conditions. The kinetics, products, and reactivity of CBZ/free chlorine reactions were investigated over the pH range of 5.5-10. Results show that free chlorine reacts with CBZ and the reactivity is pH dependent. Furthermore, the results indicate that temperature affects the reactivity of CBZ with free chlorine. The temperature experiment results were fitted with the Arrhenius equation. The calculated Ea and A values are 48.8 kJ/mol and 1.41x104 s-1, respectively. Four common intermediates were detected based on both UV and mass spectral analysis proposed structures were developed based on m/z from mass spectra. / Master of Science
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Nitrogen Removal From Dairy Manure Wastewater Using Sequencing Batch ReactorsWhichard, David P. 08 August 2001 (has links)
The purpose of this research was to characterize a flushed dairy manure wastewater and to develop the kinetic and stoichiometric parameters associated with nitrogen removal from the wastewater, as well as to demonstrate experimental and simulated nitrogen removal from the wastewater. The characterization showed that all the wastewaters had carbon to nitrogen ratios large enough for biological nitrogen removal. Analysis of carbon to phosphorus ratios showed that enough carbon is available for phosphorus removal but enough may not be available for both nitrogen and phosphorous removal in anaerobically pretreated wastewater. In addition, kinetic and stoichiometric parameters were determined for the biological nitrogen removal in sequencing batch reactors for the dairy manure wastewater. Results showed that many parameters are similar to those of municipal wastewater treatment systems. This characterization and the derived kinetic and stoichiometric parameters provided some of the information necessary for development of a nitrogen removal process in a sequencing batch reactor. Lab scale treatment of a 1:2 dilution of the anaerobically pretreated wastewater was demonstrated. Treatment was able to achieve between 89 and 93% removal of soluble inorganic nitrogen as well as up to 98% removal of biodegradable soluble and colloidal COD. In addition, a solids removal efficiency of between 79 and 94% was achieved. The lab scale treatment study demonstrated that sequencing batch reactors are capable of achieving high nitrogen removal on wastewaters with the carbon to nitrogen ratios of the dairy manure wastewater. Model simulations of the treatment process were used to develop a sensitivity analysis of the reactor feed configuration as well as the kinetic and stoichiometric parameters. The analysis of the feed configuration demonstrated the advantage of decreasing the amount of feed that is fed in the last feed period so that the effluent nitrate will be minimized. The analysis indicated that the autotrophic growth rate is one of the most important parameters to measure while error in the heterotrophic decay or yield values can lead to miscalculations of oxygen required for treatment. / Master of Science
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Designing a framework to guide renewal engineering decision-making for water and wastewater pipelinesManiar, Saumil Hiren 08 September 2010 (has links)
Federal, state and private organizations have an urgent need for renewal of water and wastewater pipelines. A pertinent gap remains in understanding the relationship between deteriorated host-pipe conditions and renewal products cost and performance. This work provides a framework Decision-Support System that supports water and wastewater pipeline renewal-products. Various renewal products fit utility needs, and the optimization of this process streamlines the decision-making for renewal product selection. The Thesis has classified various factors for use in the renewal product decision-making process, and it provides the justification for use of the renewal decision-making factors in recommending a product. Pipeline problem definition, system causes, system requirements and renewal product characteristics are the key decision-making areas controlling the recommendation of a renewal product. The Decision-Support System framework is developed in a user-friendly Visual Basic forms, using Microsoft tools and evaluated for vendor information. The given framework allows the user to edit product information needs, factors affecting decision-making and the classification of each factor. This allows for ease in modification, utilization and collaborative understanding. The prototype framework An online hosting of the proposed framework will improve accessibility and validity of the renewal decision-making process. / Master of Science
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Potential of Saudi natural clay as an effective adsorbent in heavy metals removal from wastewaterKhan, M.I., Almesfer, M.K., Danish, M., Ali, I.H., Shoukry, H., Patel, Rajnikant, Gardy, J., Nizami, A.S., Rehan, M. 25 March 2022 (has links)
No / This study aims to examine the potential of natural clay mineral from the southern part of Saudi Arabia as an effective adsorbent material for the removal of heavy metal ions of cadmium (Cd) and nickel (Ni) from aqueous solutions. The SEM analysis showed that clay particles had mixed shapes such as elongated rod-like and rectangular shape having rough corners with larger particles of 2-8 µm in size and smaller particles in the sub-micron size range. X-ray diffraction data revealed that clay particles had a good crystalline structure and composed of a mixture of various minerals including feldspar, illite, quartz, calcite, and gypsum. The BET surface area was found to be 35 ± 1 m ² /g and the average pore size and pore volume of 6.5 ± 0.5 nm and 5.7e-02 cc/g, respectively. The X-ray fluorescence analysis of clay showed main compounds of SiO₂ (47.33%), Al₂O₃ (18.14%), Fe₂O₃ (15.89%) with many others such as CaO, MgO, TiO₂, and K₂O in minor quantities. It was found that 1.2 g of clay removed up to 99.5% of Ni and 97.5% of Cd from 40 ppm aqueous solutions. The metal removal efficiencies were increased from around 95% up to 99% by increasing the pH of aqueous solutions from 4 to 11. The adsorption of Ni and Cd ions on Saudi clay was relatively fast, and up to 97% of ions were removed from solution within 45 min. The SEM-EDX and BET analysis for recycled clays further confirmed that the metal ions were removed from water through adsorption onto the clay. The experimental data fitted well with Langmuir and Freundlich isotherms. The maximum adsorption capacity of clay for Cd and Ni from isotherms was found to be 3.3 and 2.7 mg/g respectively. The findings of this study confirm the potential role of Saudi natural clay in wastewater treatment processes as a cheap, environment-friendly and safe natural adsorbent material. / The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work through research groups program under grant number R.G.P1./97/40.
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Evaluation of spray irrigation as a methodology for on-site wastewater treatment and disposal on marginal soilsMonnett, Gregory Thomas 03 August 2007 (has links)
Two field sites with soil limitations, supported by column and laboratory studies, were used to evaluate spray irrigation as an alternative methodology for onsite wastewater treatment and disposal. The first site was located in Montgomery Co., VA on a Chilhowie soil (very-fine, mixed, mesic Typic Hapludalf) and the second was located in Alleghany Co., VA on a variant of the Monongahela series (fine-loamy, mixed, mesic Typic Fragiudult). Secondary pretreatment and disinfection of the effluent was performed before application through a slow rate spray irrigation system to the soil-plant system. Effluent application rates were based on the hydraulic and N assimilative capacities of the soil-plant system. Effluent applications of 1.25 and 2.5 cm wk⁻¹ were examined at both sites.
After 20 months of effluent application at the Montgomery Co. site and 12 months of application at the Alleghany Co. site, adequate wastewater renovation was occurring in both sites. Water analyses at the 60 cm depth showed no potential groundwater contamination problems. Significant increases in chloride concentrations and EC measurements in the subsurface waters at both sites along with little or no increases in nitrate, ammonium, or phosphorus levels indicated that the effluent was being renovated as it percolated vertically through the soil profile. Runoff water quality measurements from the spray irrigation sites indicated no serious threat to nearby surface waters. Proper filtration of the sheet flow along with the relatively low loading rates, contributed to the good quality of runoff waters in both winter and summer seasons. Plant tissue analysis indicated that plant uptake of N was a large N sink during the growing season.
Denitrification column studies examined the effect of different effluent application frequencies. There were no differences between irrigation frequencies in the amount of nitrous oxide accumulated after 24 h except in columns that were suspected to contain pockets of carbon particulates which contributed to high denitrification activity. Single daily effluent applications produced extended periods of low N₂O emissions, while more frequent effluent applications produced short periods (1-3 h) of rapid N₂O emission rates immediately after effluent applications. The denitrification capacity of the soils was shown to be limited by both C and NO₃-N. Results from the denitrification column studies suggested that there is potential for optimizing N loss in spray irrigation systems by maintaining effluent in the microbially active topsoil through proper effluent application frequencies.
Both the field and column studies demonstrated that acceptable renovation of surface applied effluent by slow rate spray irrigation systems on sites with soil limitations can be obtained. / Ph. D.
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Development of Integrated Photobioelectrochemical System (IPB): Processes, Modeling and ApplicationsLuo, Shuai 24 April 2018 (has links)
Effective wastewater treatment is needed to reduce the water pollution problem. However, massive energy is consumed in wastewater treatment, required to design an innovative system to reduce the energy consumption to solve the energy crisis. Integrated photobioelectrochemical system (IPB) is a powerful system to combine microbial fuel cells (MFCs) and algal bioreactor together. This system has good performance on the organic degradation, removal of nitrogen and phosphorus, and recover the bioenergy via electricity generation and algal harvesting. This dissertation is divided to twelve chapters, about various aspects of the working mechanisms and actual application of IPB. Chapter 1 generally introduces the working mechanisms of MFCs, algal bioreactor, and modeling. Chapter 2 demonstrates the improvement of cathode material to improve the structure and catalytic performance to improve the MFC performance. Chapter 3 describes the process to use microbial electrolysis cell (MEC) to generate biohythane for the energy recovery. Chapters 4 and 5 demonstrate the application of stable isotope probing to study Shewanella oneidensis MR-1 in the MFCs. Chapters 6 to 8 describe the application of models to optimize MFC and IPB system performance. Chapter 9 describes the strategy improvement for the algal harvesting in IPB. Chapter 10 describes the application of scale-up bioelectrochemical systems on the long-term wastewater treatment. Chapter 11 finally concludes the perspectives of IPBs in the wastewater treatment and energy recovery. This dissertation comprehensively introduces IPB systems in the energy recovery and sustainable wastewater treatment in the future. / Ph. D. / The resource of pure water becomes more and more valuable, and the large discharge of the wastewater into the environment would even cause the environmental pollution. Thus, the wastewater is a necessary method to remove the organics out of the wastewater. However, the large energy consumption is a critical issue to solve due to the global energy burden. How to reduce the energy consumption in the wastewater treatment is the required step to achieve the sustainable water treatment. Integrated photobioelectrochemical system (IPB) is a new promising technology, alternative to the traditional wastewater treatment techniques (e.g., anaerobic digester or activated sludge reactor) with low energy consumption. The IPB system was to combine microbial fuel cells (MFCs), which is a typical bioelectrochemical system (BES), and the algal bioreactor together, to achieve the performance on the organic degradation, removal of nitrogen and phosphorus in the wastewater, and recover the bioenergy via electricity generation and algal harvesting. The system was proved to be effective, but most of the IPB systems were only proved to work in the laboratories, and there is still a large potential space to improve the IPB system performance in the actual environment. Herein, this dissertation combines multiple studies about the IPB improvement and scaled-up process in the real wastewater treatment. Chapter 1 generally introduces what are MFCs, algal bioreactor and modeling simulations. Chapter 2 demonstrates the method about how to improve the MFC material to enhance the treatment performance for better MFC performance. Chapter 3 describes how to use BES to convert the organics to the renewable gas (e.g., H₂ and CH₄) to recover the energy. Chapters 4 and 5 demonstrate the application of stable isotope probing to study the microbial behavior in the MFC. Chapters 6 to 8 describe the applications of model simulations to optimize MFC and IPB performance. Chapter 9 describes the new reactor to improve the algal harvesting process to obtain more energy from the IPB system. Chapter 10 describes how to use the scale-up IPB system to treat the real wastewater treatment. Chapter 11 finally puts forward some perspectives of IPBs in the wastewater treatment and energy recovery. This dissertation comprehensively gives a big picture about the development of IPB systems in the energy recovery and sustainable wastewater treatment in the future.
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Exploring Forward Osmosis Systems for Recovery of Nutrients and WaterWu, Zhenyu 19 January 2018 (has links)
Livestock wastewater contains a large amount of nutrients that are available for recovery. In this study, a proof of concept process based on forward osmosis (FO) was proposed and investigated for in-situ formation of struvite from digested swine wastewater. This FO system took advantage of a drawback reverse solute flux (RSF) and used the reversed-fluxed Mg^{2+} for struvite precipitation, thereby accomplishing recovery of both water and nutrient. With 0.5 M MgCl2 as a draw solution, high purity struvite formed spontaneously in the feed solution and the water flux through the FO membrane reached 3.12 LMH. The precipitated struvite was characterized and exhibited a similar composition to that of commercial struvite. The FO system achieve >50% water recovery, >99% phosphate recovery (given sufficient magnesium supply), and >93% ammonium nitrogen removal from the digested swine wastewater. The recovered products (both struvite and water) could potentially generate a value of 1.35 $ m^{-3}. The results of this study have demonstrated the feasibility of nutrient recovery from livestock wastewater facilitated by FO treatment. / Master of Science / Forward Osmosis (FO) effectively separates water from dissolved solutes with a semi-permeable membrane. This separation feature can be used in real water body to recover nutrients, concentrate wastewater for further treatment and produce energy for power plant. And the water body rich in nutrients induces the plants growth. These plants consume tons of oxygen in the water which decrease biodiversity in the water body, cause new species invasion and economical lose. The nutrients-rich water has caused trouble to our human being for decades, and one of them is livestock wastewater. Specifically, in this study, the piggery wastewater was used to be treated by FO system. FO has not been used to treat piggery waste/wastewater without additive from previous literature review. In this study, a FO reactor was built up for in-situ nutrient recovery as struvite, which is a valuable slow-release fertilizer. The experiments from this study proved the concept for in-situ struvite recovery from digested livestock wastewater via FO treatment with simultaneous water recovery, and will encourage further exploration of FO promoted resource recovery form wastes.
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