Dissertationen zum Thema „Agricultural wastewater treatment“
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Geber, Ulrika. „Integration of wastewater treatment in agro-ecosystems /“. Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-5745-9.pdf.
Der volle Inhalt der QuelleAlka, U. „Integration of urban wastewater treatment with agricultural reuse in developing countries“. Thesis, University of Newcastle Upon Tyne, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354418.
Der volle Inhalt der QuelleSarikaya, Ebru. „Agricultural Reuse Of Water And Nutrients From Wastewater Treatment In Izmir Region“. Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614337/index.pdf.
Der volle Inhalt der QuelleLefebvre, Louis. „Bioflocculation of Wastewater Treatment Pond Suspended Solids“. DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/904.
Der volle Inhalt der QuelleTwohig, Eamon. „Evaluating Methane Emissions from Dairy Treatment Materials in a Cold Climate“. ScholarWorks @ UVM, 2012. http://scholarworks.uvm.edu/graddis/231.
Der volle Inhalt der QuelleVALENCIA, CLAUDIA ALEXANDRA VIZCARRA. „APPLICATION OF ACTIVATED CARBON AND OTHER CARBONACEOUS MATERIAL IN THE TREATMENT OF AGRICULTURAL WASTEWATER“. PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10607@1.
Der volle Inhalt der QuelleCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
A partir do trabalho de campo feito na região agrícola de Nova Friburgo, RJ, determinou-se que o pesticida Paraquat é altamente usado. Investigou-se o processo de adsorção com carvão ativado e carvão vegetal deste pesticida em solução aquosa, como uma alternativa para o tratamento de águas residuarias da região. Foi utilizado um resíduo de carvão vegetal, denominado carvão A; e dois carvões ativados comerciais de procedências distintas, denominados respectivamente de carvão B (Brasil) e carvão C (EUA). Realizou-se uma oxidação química com HNO3 do carvão brasileiro, sendo o carvão assim tratado denominado carvão B1. Os estudos de adsorção foram precedidos de um estudo de caracterização dos carvões utilizados, através de microscopia eletrônica de varredura (MEV) e espectroscopia de dispersão de raios X (EDS), para a sua caracterização morfológica. Da isoterma de adsorção de nitrogênio a 77 K, obtiveram-se dados do volume de microporos, área superficial e distribuição de tamanhos dos poros. Espectros de FT-IR detectaram a presença de grupos funcionais nas superfícies e medições de potencial zeta permitiram a determinação do ponto isoelétrico para cada carvão estudado. No processo de adsorção em batelada foram avaliados os efeitos do pH e do tempo para se alcançar o equilíbrio. Foram levantadas experimentalmente isotermas de adsorção para os quatro tipos de carvão. Os carvões ativados B, B1 e C se ajustaram satisfatoriamente ao modelo de isoterma de Freundlich. Estas isotermas forneceram informação a respeito das capacidades de carregamento desses carvões. No estudo da cinética de adsorção, foram avaliadas as correlações dos modelos de pseudo-primeira ordem e pseudo-segunda ordem com os dados experimentais obtidos. Finalmente, os testes preliminares em coluna, em regime contínuo, permitiram a obtenção da curva de carregamento (curva de breakthrough) para o carvão ativado comercial de fabricação brasileira.
According to the work performed in the agricultural region in Nova Friburgo, RJ; it was determined that the Paraquat Pesticide is highly used. There have investigated the adsorption process with activated carbon and vegetal charcoal for pesticide treatment in aqueous solution, this will an alternative for the wastewater treatment in this region. The experimental study was conducted for a vegetal charcoal and two kinds of porous carbonaceous materials. The first of those was a charcoal made of Eucalyptus spp. wood shavings (carbon A). The second was Brazilian activated carbon (carbon B) made of coconut shell. The third material was an American coconut shell activated carbon (carbon C). The Brazilian activated carbon was further submitted to chemical modification treatment procedure with HNO3 (carbon B1). The tests of adsorption were preceded by study of characterization of the used carbons, through techniques such as scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), for its morphologic characterization. The nitrogen adsorption isotherm at 77 K, obtained data of micropore volume, superficial area and poro size distribution. Besides, the FT-IR spectroscopy detected the surfaces functional groups and the Zeta Potential Zeta determinate of the isoelectric point for each carbon. The main parameters influencing adsorption treatment process, pH and equilibrium time have been examined. There have been experimentally made adsorption isotherms for the four types of carbons, which for the carbons (B, B1 and C) adjust to the Freundlich isotherm model. The uptakes capacities information of carbons was originated by these isotherms. The pseudo-first order model and pseudo-second order model was used for evaluated the kinetic data experimental in this process. Finally, the preliminary tests in column had given a vision about of the continue adsorption and the breakthrough curve formation.
Hofstedt, Charlotta. „Wastewater use in Agriculture in Andhra Pradesh, India : An evaluation of irrigation water quality in reference to associated health risks and agricultural suitability“. Thesis, Uppsala University, Department of Earth Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88888.
Der volle Inhalt der QuelleAnvändandet av obehandlat avloppsvatten inom jordbruket är en växande företeelse i många delar av världen. Speciellt i vattenfattiga områden där avloppsvattnet ses som en värdefull och pålitlig resurs. Det höga näringsinnehållet minskar behovet av konstgödsel och detta ökar böndernas inkomster. Men med användandet av avloppsvattnet följer vissa hälsorisker. Bland annat har man sett en högre förekomst av inälvsmaskar hos bönder som använder orenat avloppsvatten jämfört med de som använder rent vatten. Den här vattenkvalitetstudien har utförts längs floden Musi i Andhra Pradesh, Indien. Musi rinner igenom staden Hyderabad och mycket av stadens avloppsvatten dumpas i floden. Nedströms Hyderabad används detta vatten för bevattning. Längs med floden är dammar byggda, för att avleda vattnet i bevattningskanaler. Reservoirer bildas då flödeshastigheten minskar. Studieområdet sträcker sig från Hyderabad och 28.7 km nedströms. Hypotesen var att reservoirerna fungerar som biodammar och syftet var att kvantifiera dammarnas inverkan på vattenkvaliteten och utvärdera dess lämplighet utifrån ett hälso- och jordbruksperspektiv. Inom studieområdet är reningen med avseende på BOD, Nematoder och E coli 86,9%, 99,9% respektive 99,9%. Trots att reningen är så hög överstiger Nematod- och E coli-koncentrationerna Världshälsoorganisationens riktlinjer och utgör en hälsorisk för bönder och konsumenter. Syre- och salthalt ökar nedströms och den höga salthalten kan ha negativ inverkan på jordbrukets avkastning. Genom att titta på reningsmönster och förändring av olika vattenkvalitetsparametrar är en av slutsatserna av detta arbete att reningen i dammarna motsvarar den rening som sker i de anaeroba bassängerna i ett biodammsystem.
The use of untreated domestic sewage in agriculture is a growing practice in many parts of the world. It is being looked upon as a valuable and reliable resource in water scarce communities. Wastewater is usually rich in nutrients and the use results in high yields without the need for artificial fertilisers. But with the use of untreated wastewater follows a number of associated health risks, e.g. a higher prevalence of helminth infections has been seen among wastewater users compared to non-users. This water quality study was performed along the River Musi in Andhra Pradesh, India. The Musi River flows through the city of Hyderabad carrying the most of the town’s wastewater. Downstream of Hyderabad the wastewater is used by farmers for irrigation. Along the river weirs are constructed which diverts the irrigation water into canals and reservoirs are formed where the flow velocity slows down. The study area stretches from Hyderabad and 28.7 km downstream. The hypothesis was that the existing irrigation infrastructure acts like Wastewater Stabilisation Ponds and the aim was to quantify the impact of the weirs on water quality and to evaluate the irrigation water quality in reference to associated health risks and agricultural suitability. Within the study area the BOD, E coli and Nematode removals were 86.9%, 99.9% and 99.9% respectively. Despite the high removal the E coli and Nematodes, the concentrations exceed WHO guidelines for unrestricted and restricted irrigation, and there exists an excess risk of intestinal nematode- and enteric infections for farmers. Dissolved oxygen and salinity increases downstream and due to the high salinity farmers could experience reduced crop yields. By looking at removal patterns, and the change in water quality parameters, the conclusion can be made that the reservoirs act like anaerobic ponds in a Wastewater Stabilisation Pond system.
Chen, Feng. „Evaluating the Performance of Sand/Gravel Bioreactors in Treatment of High Strength, High Salinity Wastewater“. The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461076223.
Der volle Inhalt der QuelleToledo, De Leon Rogelio. „Predicting Hydrological Performance of Engineered (Curtain) Drains for On-Site Wastewater Treatment Systems Installed in Poorly Drained Soil“. The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1417713887.
Der volle Inhalt der QuelleGhumrawi, Marwa Jamal. „Potential for Nitrogen Losses from On-Site Wastewater Treatment Systems on Poorly Drained Soils to Curtain Drains“. The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1471876488.
Der volle Inhalt der QuelleKromrey, Natalie A., und University of Lethbridge Faculty of Arts and Science. „The effects of wastewater treatment plant effluent and agricultural runoff on the reproductive systems of fathead minnow, Pimephales promelas“. Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, c2009, 2009. http://hdl.handle.net/10133/2519.
Der volle Inhalt der Quellexi, 104 leaves : ill. (some col.), maps ; 29 cm
Lansing, Stephanie A. „Performance and Optimization of Low-cost Digesters for Energy Production and Treatment of Livestock Wastewater“. The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1223474543.
Der volle Inhalt der QuelleTalley, Mary Katherine. „Analysis of a pilot-scale constructed wetland treatment system for flue gas desulfurization wastewater“. Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/15070.
Der volle Inhalt der QuelleDepartment of Biological and Agricultural Engineering
Stacy L. Hutchinson
Coal-fired generation accounts for 45% of the United States electricity and generates harmful emissions, such as sulfur dioxide. With the implementation of Flue Gas Desulfurization (FGD) systems, sulfur dioxide is removed as an air pollutant and becomes a water pollutant. Basic physical/chemical wastewater treatment can be used to treat FGD wastewater, but increased regulations of effluent water quality have created a need for better, more economical wastewater treatment systems, such as constructed wetlands. At Jeffrey Energy Center, north of St. Mary’s, KS, a pilot-scale constructed wetland treatment system (CWTS) was implemented to treat FGD wastewater before releasing the effluent into the Kansas River. The objectives of this study were to 1.) determine if a portable water quality meter could be used to assess water quality and track pollutant concentrations, 2.) develop a water balance of the CTWS, 3.) generate a water use coefficient for the CWTS, and 4.) create a mass balance on the pollutants of concern. Water quality measurements were taken with a HORIBA U-50 Series Multi Water Quality Checker and compared to analytical water tests provided by Continental Analytic Services, Inc. (CAS) (Salina, KS). The water balance was created by comparing inflows and outflows of data determined through flow meters and a Vantage Pro2™ weather station. Information from the on-site weather station was also used to compute the system water use coefficient. Water sampling was conducted from date to date at 10 locations within the CWTS. In general, there was little to no relationship between the HORIBA water quality measurements and the analytical water tests. Therefore, it was recommended that JEC continue to send water samples on a regular basis to an analytical testing laboratory to assess the CWTS function and track pollutants of concern. Because the water balance was conducted during system initiation, there was a great deal of fluctuation due to problems with the pumping system, issues with the upstream FGD treatment system, extreme weather events, and immature vegetation. This fluctuation resulted in the system having a non-steady state operation, which weakened the ability to calculate a system water use coefficient. However, during periods of strong system function, the water use coefficient was similar to previous studies with maximum water use being approximately equal to the reference evapotranspiration. The results of the mass balance indicated high removals mercury, selenium, and fluoride, but low removals of boron, manganese, chloride, and sulfate were exported from the CWTS.
Starnes, Daniel L. „THE EFFECTS OF MANUFACTURED NANOMATERIAL TRANSFORMATIONS ON BIOAVAILABILITY, TOXICITY AND TRANSCRIPTOMIC RESPONSES OF CAENORHABDITIS ELEGANS“. UKnowledge, 2016. http://uknowledge.uky.edu/pss_etds/74.
Der volle Inhalt der QuelleRinquest, Zainab. „Poultry slaughterhouse wastewater treatment using a static granular bed reactor (Sgbr) coupled with a hybrid sidestream membrane bioreactor“. Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2638.
Der volle Inhalt der QuelleAn increase in the demand for poultry products coupled with the potable water shortages currently experienced in South Africa (SA), attributed to climate change among other factors, makes it crucial for SA to develop water conservation strategies to minimize potable water consumption by water-intensive industries, such as the poultry industry. The development of innovative wastewater treatment processes is therefore paramount in attempting to counteract the large quantity of wastewater generated as well as to manage the environmental health concerns arising from poultry slaughterhouse wastewater (PSW) discharge into the environment. Moreover, increasing wastewater treatment costs and the implementation of increasingly stringent government legislation to mitigate environmental pollution whilst minimizing fresh water source contamination, requires that wastewater such as PSW, be adequately treated prior to discharge. This study, investigated the feasibility of treating PSW from a poultry slaughterhouse to: 1) a water quality standard compliant with industrial wastewater discharge standards and 2) for possible re-use purposes. The performance of a lab-scale PSW treatment system consisting of an anaerobic static granular bed reactor (SGBR) followed by single stage nitrificationdenitrification (SSND) bioreactor and sidestream ultrafiltration membrane module (ufMM) post-treatment systems, were evaluated, with the objective being to: assess the treatment efficiency of the individual treatment systems namely; the SGBR, SSND bioreactor, and ufMM, under varying operational conditions, as well as to determine the performance of the overall designed PSW treatment system. The down-flow SGBR (2 L) was used to reduce the organic matter (COD, BOD5, and FOG) and total suspended solids (TSS) in the PSW. Anaerobic granules from a full-scale mesophilic anaerobic reactor treating brewery wastewater were used to inoculate the SGBR, and the PSW used as feed was obtained from a local poultry slaughterhouse (Western Cape, South Africa). The SGBR was operated continuously at mesophilic temperature (35-37 °C) without pH modification and under varying HRTs (24, 36, 48, 55, and 96 h) and OLRs (0.73 to 12.49 g COD/Lday), for a period of 138 days. The optimization of the SGBR, with regard to a suitable HRT and OLR, was determined using response surface methodology (RSM) and Design Expert® 10.0.3 statistical software. Periodic backwashing of the SGBR system was performed using stored effluent, i.e. treated PSW.
Bezerra, Keyve Mayane. „Characterization of sludge generated at wastewater treatment plants health of the metropolitan region of Fortaleza aiming its use in agriculture“. Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12683.
Der volle Inhalt der QuelleA elevada produÃÃo de lodo nos grandes centros urbanos, aliada à necessidade de destinaÃÃo final adequada, tem gerado sÃrios problemas ambientais no paÃs. A maior parte do lodo produzida no mundo à destinada à incineraÃÃo, disposiÃÃo em aterros e uso agrÃcola. Dentre as alternativas de reaproveitamento, uma tÃcnica viÃvel à a utilizaÃÃo como adubo orgÃnico, devido aos nutrientes contidos, tornando-o um insumo com elevado valor econÃmico. O objetivo desse trabalho foi caracterizar o lodo proveniente de estaÃÃes de tratamento de esgotos sanitÃrios situadas na RegiÃo Metropolitana de Fortaleza, visando à reutilizaÃÃo na agricultura e possibilitando rotas alternativas para seu destino final. Foram realizadas coletas mensais de lodo no perÃodo de agosto a novembro de 2013. ApÃs a coleta, foi realizada a anÃlise dos parÃmetros: temperatura, pH, alcalinidade total, condutividade elÃtrica, Alcalinidade de Ãcidos VolÃteis (AAV), Ãcidos Graxos VolÃteis (AGV), peso especÃfico, teor de umidade, sÃrie de sÃlidos e nitrogÃnio, fÃsforo total, Demanda QuÃmica de OxigÃnio (DQO), alÃm de Coliforme total e Escherichia Coli e substÃncias inorgÃnicas (metais pesados e alguns nutrientes). Os resultados obtidos indicam que os lodos contÃm nutrientes, como nitrogÃnio e fÃsforo, necessÃrios ao crescimento das plantas, podendo ser utilizados como forma de reciclagem na agricultura, proporcionando um destino ambientalmente favorÃvel, desde que passe por um tratamento adequado para a remoÃÃo ou reduÃÃo dos patÃgenos antes de sua aplicaÃÃo. Todos os lodos apresentaram-se estÃveis para fins de utilizaÃÃo agrÃcola, visto que no estudo foi encontrada uma relaÃÃo SV/ST menor que 0,70. De acordo com a concentraÃÃo de metais pesados, eles poderiam ser reutilizados na agricultura, pois apresentaram baixos valores em relaÃÃo aos limites estabelecidos na legislaÃÃo braseileira, porÃm hà restriÃÃo, apenas, ao lodo sÃptico, devido à faixa de concentraÃÃo do zinco exceder o limite mÃximo de concentraÃÃo permitido pela ResoluÃÃo n CONAMA 375/2006.
The high production of sludge in large urban centers, coupled with the need for proper disposal, has generated serious environmental problems in the country. Most of sludge produced worldwide is intended for incineration, landfilling and agricultural use. Among the alternatives to reuse a viable technique is to use as organic fertilizer because the nutrients contained, making it an input with high economic value. The aim of this study was to characterize the sludge from the wastewater treatment plants located in the Metropolitan Region of Fortaleza, in order to reuse in agriculture and providing alternative routes to their final destination. Monthly samples of sludge were carried out in the period August to November 2013 After collection, the analysis of the parameters was performed: temperature, pH, total alkalinity, conductivity, alkalinity of Volatile Acids (AAV), Volatile Fatty Acids (VFA) , specific weight, moisture content, solids and nitrogen, total phosphorus, chemical oxygen demand (COD), and Total Coliform and Escherichia Coli and inorganic substances (heavy metals and some nutrients). The results indicate that the sludge contains nutrients such as nitrogen and phosphorus necessary for the growth of plants and may be used as a form of recycling in agriculture, providing an environmentally friendly target, provided that pass through a suitable treatment for the removal or reduction of pathogens before its application. All slurries exhibited stable for agricultural use, whereas in one study SV / ST ratio less than 0.70 was found. According to the concentration of heavy metals, they could be reused in agriculture, as had lower values compared with the limits established in legislation braseileira, but no restriction, just, septic sludge, due to the concentration range of zinc exceeds the maximum limit concentration permitted by CONAMA Resolution No. 375/2006.
Basitere, Moses. „Performance evaluation of an up- and down-flow anaerobic reactor for the treatment of poultry slaughterhouse wastewater in South Africa“. Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2632.
Der volle Inhalt der QuelleThe process of anaerobic digestion (AD) is one of the most cost-effective and environmentally sustainable technologies to treat wastewater in the agricultural sector. In South Africa, in some industries in the agricultural sector, such as the poultry industry in particular, slaughterhouses have the highest consumption of potable water, culminating in the production of a large quantity of high strength wastewater. This high consumption of potable water has become a concern in South Africa due to water scarcity and reduced rainfall attributed to global warming, including weather changes. Furthermore, the generation of a large volume of wastewater poses environmental pollution concerns. The wastewater from poultry slaughterhouses can be quite easily treated to a suitable quality for reuse, using various bioreactor systems that utilise low cost anaerobic digestion processes. However, as this wastewater contains a high quantity of biodegradable organic matter – with the primary pollutants being proteins, blood, fats, oil and grease (FOG) – selecting a suitable anaerobic reactor configuration (up-flow vs down-flow) plays an important role in achieving high reactor performance. In this study, both the up-flow, (i.e. Expanded Granular Sludge Bed Reactor) and the down-flow (i.e. Static Granular Static Granular Bed Reactor), were studied to quantitatively determine their performance in treating poultry slaughterhouse wastewater. Firstly, the feasibility of treating poultry slaughterhouse wastewater with an up-flow Expanded Granular Sludge Bed Reactor (EGSB) coupled with anoxic and aerobic bioreactors was investigated at an HRT of 7 (168 hr), 4 (96 hr) and 3 (72 hr) days using organic loading rates of 0.5, 0.7 and 1.0 gCOD/L.day. The averaged tCOD removal for the EGSB reactor was 40%, 57% and 55%, respectively, at the various OLRs and HRTs investigated. The overall tCOD removal of the system (EGSB-anoxic/aerobic) at high OLR of 1.0 gCOD/L.day was increased to 65%. The redundant performance of the up-flow EGSB reactor was attributed to the periodical sludge washout experienced during its operation due to high FOG and TSS concentrations in the influent. Due to the periodic sludge washout, the reactor required continuous re-inoculation resulting in the EGSB being operated for a short period (i.e. 26 days). As a result of such system deficiency, it was recommended that to improve the performance of the up-flow EGSB reactor in treating poultry slaughterhouse wastewater, a pre-treatment system – such as a Dissolved Air Floatation system (DAFs) or a FOG skimmer – is required to reduce the FOG and total suspended solids (TSS) load prior to the wastewater fed to the EGSB. This will minimise system failure and the need for a continuous re-inoculation of the system (see Appendix C for improved operation strategy of the EGSB reactor). Furthermore, a system redesign was recommended, thus the use of the SGBR. Secondly, after the EGSB system evaluation, the performance of a down-flow system (i.e. SGBR) for the new design, the following were deemed appropriate for improved system (SGBR) design: 1) reduced HRT for high wastewater treatment through-put rates; 2) the ability to adequately treat the wastewater with higher organic loading rates; and 3) reduction of the plant footprint by using a membrane filtration system (i.e. a single process unit) to effectively reduce process requirements needed for the anoxic/aerobic bioreactors (i.e. n=2 process unit) used with the EGSB. Similarly, for large-scale operations, it is advisable to have a backwash system to adequately handle declogging processes (i.e. these systems modifications were evaluated in the SGBR). The SGBR, coupled with an ultra-filtration (UF) membrane system, was then investigated for treating the poultry slaughterhouse wastewater at an HRT of 55 hrs and 40 hrs, including average OLRs of 1.01 and 3.14 gCOD/L.day, respectively. The average maximum performance of the SGBR in terms of tCOD, TSS and FOG removal was > 90% at the OLRs and HRTs investigated. The UF membrane system used as a post-treatment system further yielded a system performance improvement for tCOD, TSS and FOG of 64%, 88% and 60%, respectively. The overall performance of the combined system (SGBR and UF membrane system) in terms of tCOD, TSS and FOG removal was 98%, 99.8% and 92.4%, respectively. The highest performance for the down-flow SGBR was attributed to its ability to retain granulated sludge in the reactor while maximizing the digestion of the organic matter fed into the reactor, even at higher OLRs. Furthermore, for effective declogging, the implementation of a periodic backwash system to effectively remove dispersed fine sludge particles in the underdrain and excessive suspended solids entrapment was observed to ease the system operational deficiencies.
Mancl, Karen M. „Environmental Technology Transfer to Rural China“. The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275426853.
Der volle Inhalt der QuelleFurtado, Ricardo Dourado. „Tratamento de efluentes gredaos pela lavagem de aeronaves agrícolas e pelo descarte das aplicações aéreas de agrotóxicos“. reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/70046.
Der volle Inhalt der QuelleThis thesis aims to analyze the efficiency of a system for treating wastewater generated by the washing of agricultural aircraft and the disposal of unused pesticides in aerial application. The system consists of waterproof floor washing, settling pit tank, oxidation system using ozone and volatilization bed. This study was divided into two phases. In Phase 1, followed up campaigns of aerial applications, collecting data such as: amount of effluent generated, water consumed and the pesticides used to generate informations for the proposed study and know the environmental impact of aerial application of pesticides.The average water consumption was 112.8 L and the production of effluent was 132.8 L by washing.In Phase 2, were done physical and chemical analysis, concentration and charge of the active principles of pesticides in the effluent, in the steps of treatment system.The effluent was subjected to two distinct rates of ozone, 1.0 and 2.0 g O3/hour to assess the degree of degradation by the difference of concentration.The system reduced concentrations of Pyraclostrobin of the effluent in 97%, Epoconazole 98.1%, Imazethapyr 92.4%, Imazapic 91,8% and Flufenoxuron 82.8% for the rate of 1.0 g O3/hour, and to 2.0 g reduced Pyraclostrobin concentration in 85.1% , Epoconazole 97.1%, Imazethapyr 97.1%, Imazapic 94.7% and Flufenoxuron 86.0%.With the reduction of the load from the Sample 1 (without the effect of Sample C.O.), it was found that there was a reduction of Pyraclostrobin in 90.8%, Epoconazole 73.0%, Imazethapyr 69.1%, Imazapic 71,8% and Flufenoxuron 44.8% to rate O3/ hour 1.0 g, and for 2.0 g Pyraclostrobin decreased 50.3%, Epoconazole 59.3%, Imazethapyr 80.7%, Imazapic 82.4% and Flufenoxuron 63.2%. The Chemical Oxygen Demand of effluent pesticides after completing treatment showed values above allowed to release into the environment legislation, especially CONSEMA Resolution 128/2006 limiting at 400 mg O2/L for flows less than 20 m3/day. Cascade equals 2165.00 with COD mg O2/L, Opera 4191 mg O2/L, and Only with 668.50 mg O2/L. The treatment system worked decreasing the concentration and the load of pesticides and retained the final product of the treatment, given the agricultural and environmental legislation, and the economic and technical characteristics of agricultural aviation companies.
Gunn, Kpoti Mawutodzi. „Developing Strategies For Year-Round Spray Irrigation of Wastewater Effluent in Ohio“. The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1262207613.
Der volle Inhalt der QuelleHenderson, Kelsey. „Reverse Osmosis as a Chemical-Free Technology for the Removal of Nutrients from Cure Meat Processing Wastewater“. The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1563470474960378.
Der volle Inhalt der QuelleUhlířová, Marcela. „Využití membrán pro zpracování odpadních vod ze zemědělství“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443232.
Der volle Inhalt der QuelleLama, Felipe Morais Del. „Aproveitamento da água residual do processamento do pescado em irrigação“. Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-14112018-112541/.
Der volle Inhalt der QuelleFish processing wastewater contains high levels of organic matter, ions and microorganisms. Because of this composition, it is necessary to treat this effluent before its return to water bodies or the environment. Despite the treatment, there can be some remaining contaminants in the treated wastewater. Thus, sustainable practices regarding the wastes management, such as their reuse in agriculture, turn out to be an additional option to the treatment and an alternative to the disposal of these compounds in different ecosystems. The objective of this work was initially to perform chemical, physical and microbiological characterizations of a raw wastewater coming from a tilapia (Oreochromis niloticus) processing plant as well as the treated wastewater. The latter was collected from a waste treatment facility located beside and belonging to this same industry. There was a removal efficiency of 90% in organic matter. Nevertheless, bacteria concentration, mainly Escherichia coli, increased in the treated wastewater. Furthermore, this same liquid waste presented a medium concentration of 123.4 mg/L in nitrogen, and 10.55 mg/L in phosphorus, values considered important. These facts can be explained by the inappropriate addition, during the treatment stages, of other wastes present in the industry like human excrements. Secondly, irrigation trials were performed in lettuce (Lactuca sativa var.crispa) and its seeds by using each wastewater at concentrations of 25%, 50%, 75% and 100%. There were not any adverse effects to the seeds physiological potential. For plants which were grown in a clay substrate, the increase in the applied effluents caused lettuce to cumulate chloride (Cl-). In this respect, negative correlations between the chloride concentration in plants tissues, biomass, and shoot and root growth, were observed. There was still an increase in the plants mortality rate in lettuce irrigated with raw wastewater as the concentrations of this effluent became greater. These tests showed that the treated wastewater at concentrations of 25% and 50% had the best agronomic performance. The microbiological analyses of these treatments in turn did not reveal the presence of pathogenic bacteria present in the Brazilian laws. Despite this fact, a better management of the treatment stages is compulsory in order to achieve a safer wastewater reuse. Moreover, there can be a production of incomes, which represents an asset for ecoefficient companies
Littlefield, Joanne. „Constructed Wetlands for Dairies: Component Aids Dairy Wastewater Treatment System“. College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/622240.
Der volle Inhalt der QuelleShepherd, Jessica Grace. „Ochre and biochar : technologies for phosphorus capture and re-use“. Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28907.
Der volle Inhalt der QuelleSantos, Jeferson Gaspar dos. „Análise parasitológica em esgotos tratados utilizados na agricultura“. Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/6/6134/tde-28102010-173745/.
Der volle Inhalt der QuelleDecreased availability of good water quality worldwide is a result, among other factors, high consumption exerted by irrigated agriculture. In order to minimize the impacts caused by this activity to water, many countries demonstrate the viability of using treated sewage effluent in agriculture. However, this practice provides a public health risk through the pathogens can survive in sewage. Among these pathogens, WHO stresses the protozoa and helminths of human, because they presented greater period of survival in adverse conditions and high power of infection. This paper aims to evaluate the quality and quantity of intestinal parasites of sanitary importance present in the raw sewage in the treated effluent and disinfected from two treatment plants located in the city of Piracicaba. The sewage treatment plant CECAP comprises an Australian system with an anaerobic pond, facultative ponds primary and secondary treatment by filtration and disinfection by chlorination. The sewage treatment plant Piracicamirim consists of UASB followed by aerated lagoon, activated sludge secondary clarifiers, treatment by sand filter and disinfection by ultraviolet radiation. Between May 2008 and December 2009 were collected and samples of raw sewage effluent treated and disinfected, following the guidelines of AYRES and MARA (1996). The techniques of preparation and analysis were performed according parasitological YANKO (in 1987) and WHO (1999). CECAP showed rates of positive samples of 40 per cent for the effluent disinfected with Toxocara sp parasite more present with 46.17 eggs/l. The mean helminths eggs for the study period was 3.78 eggs/l effluent disinfected. Piracicamirim showed rates of 100 per cent for the effluent disinfected. Ascaris sp was the parasite most commonly found in the three collection sites. The mean helminths eggs for the period was 0.89 eggs/l effluent disinfected. CECAP not produced a final effluent suitable for irrigation use. Already the effluent from the sewage treatment plant Piracicamirim meets the recommendations of WHO (2006), for the presence of helminths eggs for use in unrestricted irrigation
Calabria, Jorge Luis. „Wastewater Nutrient Recovery Using Anaerobic Membrane Bioreactor Permeate for Hydroponic Fertigation“. Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5348.
Der volle Inhalt der QuelleJohnson, Hailey E. „Co-utilisation of microalgae for wastewater treatment and the production of animal feed supplements“. Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1003999.
Der volle Inhalt der QuelleSeidel, Georgetta. „Detection of non-CPE producing enteric viruses via ICC-PCR at wastewater land application sites in Arizona and California; endocrine disruption activity after wetland, pond, and soil aquifer treatment of wastewater“. Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/280323.
Der volle Inhalt der QuelleBelda, Gonzalez Alberto. „The Water-Energy-Agriculture nexus in Jordan : A case study on As-Samra wastewater treatment plant in the LowerJordan River Basin“. Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-232826.
Der volle Inhalt der QuelleHistoriskt sett har vatten-, energi- och jordbruksresurser varit naturligt begränsade i Jordanien, men de nuvarande ekonomiska, demografiska, geopolitiska och miljöbetingade förhållandena förvärrar situationen. Inkommande flyktningar ökar den redan höga populationsökningen; bättre ekonomiska förutsättningar och levnadsstandarder ändrar konsumtion- och produktionsmönster; kringliggande konflikter påverkar utbudet av resurser; och negativa effekter associerade med klimatförändringar är redan tydliga. På denna grund så är Nexus en god grund för integrerad och tvärsektoriell förvaltning av naturresurs och vital för att säkerställa resurser för vatten, energi och mat och eventuellt gå mot en hållbar utveckling inom landet. För att åstadkomma det ovannämnda så är förståelse för nuvarande nexus samband avgörande. Denna studie utgör ett tillvägagångssätt för en nexus studie med fokus på vatten, energi och jordbruk (WEA) sektorerna i Jordanien. Arbetet utgår från en fallstudie och baseras på en litteraturstudie som är gjord på tre olika nivåer: nationell, Lower Jordan River Basin inom gränserna av Jordanien och As-Samra vattenreningsverk, sistnämnda utgör fallstudien. Baserat på en omfattande litteraturstudie som resulterat i en uppdaterad analys av Jordaniens situation, så har de huvudsakliga WEA nexus sambanden identifierats för varje nivå. Tretton framtida alternativa utfall har föreslagits, deras potentiella påverkan på WEA sektorerna har undersökts och relaterade indikatorer har föreslagits för att utvärdera deras påverkan. Vidare, tre kombinerade utfall har utvärderats i detalj. Överlag så visar resultaten på starkt ömsesidigt beroende mellan WEA sektorerna på alla nivåer och är beräknad att intensifieras i framtiden, vilket betonar den kritiska situationen Jordanien befinner sig i med avseende på naturresurshantering. Ineffektivt och ohållbart utnyttjande av naturresurser står ut som ett stort problem som kräver en lösning, och framtida utfall tycks vara potentiellt skadliga för Jordanien om de inte inkluderas i en integrerad planering baserat på ett nexus tillvägagångssätt.
Dominato, Daniele Tonon. „Tratamento de efluente anaeróbio = condicionamento em filtro de areia visando lançamento e reúso“. [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258255.
Der volle Inhalt der QuelleTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: A escassez cada vez maior de água doce devido ao crescimento demográfico, a urbanização e, provavelmente, as mudanças climáticas, tem dado lugar ao uso crescente de águas residuárias na agricultura. Atualmente, essa prática é uma realidade, principalmente na região sudeste de São Paulo, onde os conflitos pelos usos múltiplos da água são constantes. Frente a essa situação, o objetivo desse trabalho foi avaliar o condicionamento de efluentes sanitários, de um sistema composto por filtros anaeróbios e pós-tratamento por filtros de areia (com espessura de 0,75 m) com altas taxas de aplicação diárias que variaram de 300 a 800 Lm-2, visando reúso agrícola e/ou para lançamento em corpos hídricos. Verificou-se uma remoção na concentração de matéria orgânica em termos de DQO, DBO e COD acima de 90 % no efluente dos filtros de areia em todas as taxas de aplicação estudadas. Os resultados apontam que o parâmetro limitador para a utilização de taxas de aplicação diárias superiores a 700 L m-2 foi a concentração de nitrogênio amoniacal produzido nos filtros de areia, superiores a 20 mg L-1, obrigando a implantação de um sistema de aeração superior. A dosagem de hipoclorito de cálcio empregada para adequar o efluente a legislação foi de 3,25 mg L-1 com um tempo de contato de 45 minutos e a classificação do efluente final para a utilização deste na agricultura foi C3S1, estando apto a ser utilizado com um grau moderado de restrição. Como os resultados foram satisfatórios, comprova-se que é possível a aplicação de maiores taxas hidráulicas nos leitos de areia
Abstract: Increasing scarcity of freshwater due to demographic growing, urbanization and, climate changing are the reason of increasing use of the wastewater in agriculture. Nowadays, this practice is a reality, mainly in São Paulo in the southeast areas, where the conflicts caused by multiples use of water are constant. Based on this situation, the aiming of this investigation was to evaluate wastewater conditioning, from a system composed by anaerobic filters and post - treated by sand filters (0,75m height) with high daily application rates which varied from 300 to 800 L m-2, agriculture reuses and/or discharging into receiving waters. An organic matter removing of 90% in terms of COD, BOD and DOC was observed in sand filters effluent in all application rates which were studied. Results have shown that the limitation parameter to use application rates over 700 L m-2 was the ammonium nitrogen concentration which are produced by sand filters and were over 20 mg L-1, forcing to implant a superior aeration system. Calcium hypochlorite dose, used to make the effluent appropriate according to the law, was 3,25 mg L-1 with a contact time of 45 minutes and the final effluent classification to use it in agriculture was C3S1, which is suitable to be used with a moderate degree of restriction. As the results were satisfactory, higher application hydraulic rates in sand filters are proved to be possible
Doutorado
Saneamento e Ambiente
Doutor em Engenharia Civil
West, Lu?s Gustavo Macedo. „Uso de efluentes dom?sticos tratados na cultura do girassol (helianthus annuus l.)“. Universidade Estadual de Feira de Santana, 2018. http://tede2.uefs.br:8080/handle/tede/659.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
Agricultural reutilization is an important tool in water demand reduction required by irrigation. The lack of proper management on irrigation generates large environmental degradation, mainly to water resources, therefore it?s indispensable the reduction of these impacts. The use of domestic wastewater in agricultural crops may support the search for alternative water sources to supply the irrigation demand even as provide essential nutrients to the crops, and also reducing the impact of the chemical fertilizers application. This dissertation aims to evaluate the use of treated domestic wastewater on sunflower irrigation (Helianthus annuus L.) cultivate ?Garden Gnome?, using treatments by sand strainer (SS), organic filter (OF), septic tank (ST) and well water (WW) applied in different levels (50, 75, 100, and 125% of evapotranspiration of daily crop). The experiment was conducted with buckets of 20 L with one plant per bucket in experimental design of 4 by 4 with 5 parcels, adding up to 80 experimental units. Physicochemical analyses on the soil were realized after application, and in the wastewater, additionally, microbiologic analyses were realized during the experiment. With the plants were realized biometric analyses: stem diameter, plant height, leaves number and phytomasses: dry and fresh phytomass from the aerial part, from the pseudostem, and from the roots. It can be conclude that the use of different irrigation sources didn?t produced significant effect in biometric evaluation and of sunflower phytomass, being possible the use of all the studied sources, without losses to the plant development. The sand filtration provided considerable efficiency, being a simple and cheap solution to the domestic wastewater treatment
O re?so agr?cola ? uma importante ferramenta na redu??o da demanda h?drica requerida pela irriga??o. A falta de manejo adequado na irriga??o provoca grande degrada??o ambiental, principalmente aos recursos h?dricos, sendo assim, se torna imprescind?vel a redu??o desses impactos. A utiliza??o de efluentes dom?sticos em cultivos agr?colas pode favorecer a busca por fontes alternativas de ?gua para suprimento das demandas de irriga??o assim como fornecer nutrientes essenciais aos cultivos, reduzindo o impacto tamb?m na aplica??o de fertilizantes qu?micos. O trabalho teve como objetivo avaliar o uso de efluentes dom?sticos tratados na irriga??o do girassol (Helianthus annuus L.) cultivar An?o de Jardim, utilizando tratamentos por filtro de areia, filtro org?nico, fossa s?ptica, e ?gua de po?o em diferentes l?minas de irriga??o aplicadas (50, 75, 100 e 125% da evapotranspira??o da cultura di?ria). O experimento foi conduzido em baldes de 20 L com uma planta por balde em delineamento experimental 4x4 com 5 parcelas, totalizando 80 unidades experimentais. Foram realizadas an?lises f?sico-qu?micas no solo ap?s aplica??o e nos efluentes adicionalmente, foram realizadas an?lises microbiol?gicas durante o experimento. Nas plantas foram realizadasan?lises biom?tricas: di?metro do caule, altura da planta e n?mero de folhas e de fitomassas: fitomassas fresca e seca da parte a?rea, do cap?tulo e da raiz. Pode-se concluir que a utiliza??o de diferentes fontes de irriga??o n?o produziu efeito significativo nas avalia??es biom?tricas e de fitomassa do girassol, sendo poss?vel a utiliza??o de todas as fontes estudadas sem preju?zo ao desenvolvimento da planta. A filtra??o de areia proporcionou efici?ncia consider?vel, sendo uma solu??o simples e barata para o tratamento de efluentes dom?sticos
Lanoux, Aurélie. „Caractérisation et rôle respectif des apports organiques amont et locaux sur l'oxygénation des eaux de la Garonne estuarienne“. Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00874532.
Der volle Inhalt der QuelleCausse, Jean. „Temporalité des transferts de nutriments dans les bassins versants à algues vertes“. Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1B012/document.
Der volle Inhalt der QuelleIn Brittany (Western France), "green tides" are recurrent since the early 70s and have an important place in public debate in health, political and economic terms. In this thesis, a wide bibliographic review was performed on the export of nitrogen, and an innovative methodology has been set up to study the spatial and temporal variability of nutrient export in two coastal watersheds on an intra-annual basis and during extreme events (rainfall events, tourist periods of low water, ...). Watersheds selected for the field experiments are Ic and Frémur (Côtes d'Armor). 3 types of experiments were performed on these watersheds: 1) Campaigns of grab samples by dry and wet weather (32 stations, 27 campaigns); 2) automatic sampling during floods (3 stations, 8 floods); and 3) high frequency measurement (2 stations, continuous). Conventional hydrological and physicochemical parameters, suspended solids, UV spectra and all forms of macronutrients (carbon, nitrogen, phosphorus) were analyzed during these experiments. The results confirm in part a number of results of the literature. Furthermore, it highlights the relationship carbon / nitrates far little studied at different spatial and temporal scales and during rainfall events, which however seems to be crucial in understanding of nitrate export. Finally, the analysis of all forms of nutrients reveals the importance of particulate forms from soil erosion. These results raise many research questions that merit further development in order to improve knowledge on nutrient transfers in watersheds and prioritize remediation actions. The prospects of this work are both scientific and practical. At the scientific level, research efforts on the relationship carbon / nitrate and identification of the assimilable fraction of organic carbon by denitrifying organisms must be continued. Similarly, the knowledge on nutrient export must be improved through the precise identification of particulate nutrient sources during the spring floods. On a practical level, it should contribute to the improvement of agricultural practices, the recognition of the interest of natural wetlands and improvement of the types of treatment used by treatment plants. The results obtained in this study should in particular be linked to the dynamics of nutrients in the foreshore observed during the development of green algae. Finally, an effort to improve access to certain types of data on watersheds is needed to improve understanding of nutrient transfers
Karunarathna, Mudugamuwe Hewawasam Jayan Savinda. „Photochemistry of iron(III) with carboxylate-containing polysaccharides for sustainable materials“. Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1586468303760847.
Der volle Inhalt der QuelleHsu, Pei-Chen, und 許珮甄. „The Effluent Reuse for Agricultural Irrigation from Municipal Wastewater Treatment Plants - A Case Study of the Pa-Li Wastewater Treatment Plant“. Thesis, 2005. http://ndltd.ncl.edu.tw/handle/zsr4wg.
Der volle Inhalt der Quelle國立臺北科技大學
環境規劃與管理研究所
93
The water demand is increasing gradually and the water resource shortages problems will be more serious in Taiwan. The reclaimed water from municipal wastewater treatment plant is actually a very reliable alternative water resource, because of its stable quantity and the lower pollution quality. In addition, the water demand of agricultural irrigation is the highest portion in Taiwan. For this reason, the objective of this study is to assess municipal treated water reuse for agricultural irrigation, including water reclamation technologies and water quality standards. In addition, the research assessed the feasibility of the effluent reuse from Pa-Li wastewater treatment plant to Tao-Yuan areas for the irrigation. The concentration of the total nitrogen from the secondary effluent could not confirm the required water quality standards. But nitrogen is an important element for the crop, therefore, to employ nitrogen removal process, dilute the concentrated of reclamation water with original irrigation water, or to adjust internal standard are available. The advantage of water reuse from the Pa-Li wastewater treatment plant to Tao-Yuan areas is the large amount of water. But the wastewater of Pa-Li wastewater treatment plant is only treated to the primary level, some water qualities could not reach the required water criteria. The study suggests using the stepping aeration process to remove organic matter and the MLE process to remove total nitrogen in the Pa-Li wastewater treatment plant. However, the feasibility is restricted by the area of factory. Considering for present master plan status of the Pa-Li wastewater plant, only 9 % of treated water can be regenerated for agricultural irrigation demand. For this reason, it is necessary to coordinate and regain the borrowed land in order to increase the area for the advanced processes.
Haverstock, Michael James. „An Assessment of a Wetland-Reservoir Wastewater Treatment and Reuse System Receiving Agricultural Drainage Water in Nova Scotia“. 2010. http://hdl.handle.net/10222/13103.
Der volle Inhalt der QuelleAfroze, Niema. „Performance Evaluation of a New Multi-Environment Wastewater Treatment System for the Removal of Carbon, Nitrogen and Phosphorus from Synthetic and Real Agricultural Wastewaters“. Thesis, 2011. http://spectrum.library.concordia.ca/35843/1/Afroze_MASc_F2011.pdf.
Der volle Inhalt der QuelleKupeta, Albert Jerry Kafushe. „Synthesis of cross-linked pine cone biosorbent and its applications in industrial wastewater treatment“. Thesis, 2014. http://hdl.handle.net/10352/340.
Der volle Inhalt der QuelleThe widespread use of phenols and phenolic derivatives in industrial applications has resulted in their discharge as part of industrial wastewater. These chemicals are toxic and need to be removed from the aqueous environment. Amongst the available pollutant removal technologies, adsorption has been widely used due to its simplicity, ease of operation, cost-effectiveness and ability to sequester pollutants at very low concentrations. Different adsorbents have been applied for removal of phenols and their derivatives. Use of agricultural waste as adsorbents seems to offer a much cheaper alternative in pollutant removal. This study examines the synthesis of a hydrophobic biomaterial composite by cross-linking of Fenton treated pine cone and applying the prepared adsorbent for 2-nitrophenol removal from aqueous solution. Pine cone biomass, in its raw and modified forms was tested for its ability to remove 2-nitrophenol from simulated industrial wastewater. The experimental procedure is divided into two main parts: (1) pine cone modification using Fenton’s reagent and 1.6-hexamethylene diisocyanate and (2) application of the prepared hydrophobic adsorbent for 2-nitrophenol removal from wastewater. Fenton’s reagent was used to remove pigments, extractives and other soluble organic compounds from the raw pine. FTIR spectroscopy showed an increase in magnitude of oxygenated surface groups which resulted in a decrease in pHpzc. The effect of Fenton treatment on further modification of the pine biomass via cross-linking using 1.6-hexamethylene diisocyanate was investigated. Optimum reaction variables for the cross-linking using dibutyltin dilaurate as catalyst under an inert nitrogen gas atmosphere in anhydrous hexane solvent were determined using FTIR spectroscopy. Success of the cross-linking procedure was confirmed by use of analytical techniques (XRD, TGA, SEM, EDX and BET surface area) and weight percent gain calculations. Pine and modified pine biomass were tested for their ability to sequester 2-nitrophenol via batch adsorption technique. The effect of pine modification on affinity for the biosorbate was investigated. The mechanism of the adsorption process was determined via use of kinetic, diffusion and equilibrium isotherm models. Two error functions (coefficient of determination and percent variable error) were employed to substantiate the model showing a good fit to the experimental adsorption data. The experimental adsorption kinetic data was fit to the pseudo-first-order and pseudo-second-order kinetic models. Due to the large size of the pollutant molecules diffusion process analysis was also conducted. The effect of pine modification on kinetic and diffusion parameters was determined. The experimental equilibrium adsorption data was fit to the Freundlich, Redlich-Peterson and Hill isotherm models. The initial shapes of the adsorption isotherms for 2-nitrophenol adsorption onto pine and modified pine biomass determined the type of equilibrium isotherm models to fit the experimental data to. Thermodynamic parameters were calculated to determine the spontaneity, feasibility and energy changes associated with the adsorption process. The degree of disorder at the solid/liquid interface after the adsorption was determined. The effect of temperature on the adsorption process was used to show whether the adsorption is physical or chemical. The effect of pine modification on equilibrium isotherm parameters was determined. The study is divided into seven chapters: Chapter 1: The chapter covers the introduction, problem statement, aim and objectives of the research. It gives an insight into the research project. Chapter 2: The literature review of pollutants in industrial wastewater and methods of their removal is dealt with in this chapter. Adsorption is introduced as an alternative technique for pollutant removal from aqueous systems. An in-depth review of various adsorbents (including pine cone), their merits and limitations are also discussed together with methods of modifying and use of modified adsorbents. Equilibrium, kinetic and thermodynamic models used to treat adsorption experimental data are presented. Chapter 3: The experimental procedures on the synthesis, characterization and application of the hydrophobic biosorbent in the removal of 2-nitrophenol from aqueous solution are presented. Kinetic and equilibrium experiments are described in detail. Chapter 4: It describes the first part of the results and discussions. The chapter focuses on optimization of reaction variables and characterization (using various analytical techniques) of the hydrophobic biomaterial composite. Chapter 5 The chapter discusses the second part of the results. It focuses on magnitude of surface charge, pHpzc and kinetic studies. Fitting of the adsorption experimental data to kinetic and diffusion models is presented together with the error functions. Chapter 6 The chapter discusses part three of the results on equilibrium studies. The adsorption experimental data is fitted to equilibrium isotherm equations and error determination is presented. Thermodynamic parameters are calculated and interpreted. Chapter 7: Conclusion and recommendations are presented. The optimum reaction variables for cross-linking of Raw and Fenton treated pine cone were determined using FTIR analysis and found to be: 0.2 g pine biomass, 3.5 cm3 1.6-hexamethylene diisocyanate cross-linker, 50 cm3 anhydrous hexane solvent, 1.5 cm3 dibutyltin dilaurate catalyst, temperature of 50 °C and a reaction time of 4 hours. The pine surface showed an increase in phenolic, lactonic and carboxylic acid groups due to the modification. The pHpzc showed a decrease due to modification of the pine cone biomass. The pHpzc values for the pine and modified pine cone biomass were found to be: Raw = 7.49, Raw-HMDI modified = 6.68, Fenton treated pine = 5.40 and Fenton-HMDI modified = 6.12. The optimum pH for the adsorption of 2-nitrophenol onto raw pine and modified pine cone biomass was determined to be 6. The optimum adsorbent dosage was determined as 1.5 g/dm3. The adsorption kinetics show a good fit with the pseudo-second-order model. This suggests that surface adsorption is the controlling step in the adsorption of 2-nitrophenol onto pine cone biomass. The analysis of diffusion processes showed that the initial rapid stage during the adsorption is due to external mass transfer processes. The adsorption experimental data also showed that pore diffusion was rate-limiting amongst the diffusion processes. Pine modification using Fenton’s reagent and 1.6-hexamethylene diisocyanate increased magnitude of kinetic and diffusion parameters. Experimental data for 2-nitrophenol adsorption onto pine and modified pine cone biomass showed better correlation with the Redlich-Peterson and Hill isotherm models and poor correlation with the Freundlich isotherm model. This suggests that the mechanism does not show complete multilayer coverage with cooperative phenomena between adsorbate molecules. Thermodynamic parameters showed that the adsorption is feasible, spontaneous, and exothermic and results in a decrease in degree of disorder at the solid/liquid interface. An increase in temperature resulted in a decrease in adsorption capacity showing that the adsorption is physical. Pine modification using Fenton’s reagent and 1.6-hexamethylene diisocyanate increased magnitude of kinetic, diffusion and isotherm parameters. The kinetic and equilibrium results show that the adsorption of 2-nitrophenol onto pine cone biomass follows the order: Fenton treated-HMDI > Fenton treated > Raw-HMDI > Raw. Hence, it can be concluded that Fenton treatment and HMDI cross-linking modification did increase the adsorptive capabilities of the pine cone biomass.
VUT Research Directorate
HUANG, YU-MIN, und 黃昱閔. „Water quality purification for agricultural and municipal wastewater by surface flow treatment system in Linluo constructed wetland - a case study“. Thesis, 2012. http://ndltd.ncl.edu.tw/handle/84683321800188111837.
Der volle Inhalt der Quelle大仁科技大學
環境管理研究所
100
This work we access a free-surface-flow constructed wetland treatment system receiving agricultural runoff and were used to determine water purification efficiency performance in Lin Lo Wetland Park. The access items including: DO, EC, Turbidity, SS, BOD, COD, TN, TP, Chlorophyll-a etc. The process parameters: influent rate 506-1270 CMD, effluent rate 60-173 CMD, hydraulic loading rate 0.042-0.104 m/d, and hydraulic retention time 4.13-9.72day were determined in Lin Lo Wetland Park. Treatment efficiency in parameter SS were: influent concentration 26 mg/L, PLR 1.56 g/m2-d, effluent concentration 10.0 mg/L, Removal Rate 0.90 g/m2-d, good removal efficiency 78%. Treatment efficiency in parameter BOD were: influent concentration 5.64 mg/L, PLR 0.40 g/m2-d, effluent concentration 3.18 mg/L, Removal Rate 0.17 g/m2-d, removal efficiency 66%. Treatment efficiency in parameter COD were: influent concentration 21.4 mg/L, PLR 1.52 g/m2-d, effluent concentration 5.7 mg/L, Removal Rate 1.10 g/m2-d, removal efficiency 70%. Treatment efficiency in parameter NH3-N were: influent concentration 0.99 mg/L, PLR 0.06 g/m2-d, effluent concentration 0.18 mg/L, Removal Rate 0.05 g/m2-d, removal efficiency 95%. Treatment efficiency in parameter TN were: influent concentration 6.23 mg/L, PLR 0.46 g/m2-d, effluent concentration 1.46 mg/L, Removal Rate 0.35 g/m2-d, good removal efficiency 60%. Treatment efficiency in parameter TP were: influent concentration 1.85 mg/L, PLR 0.14 g/m2-d, effluent concentration 0.19 mg/L, Removal Rate 0.12 g/m2-d, good removal efficiency 98%. Owing to high temperature and enough sunshine, the removal efficiency of fecal coliform was 83-100%. It’s helpful to wetland manager by monitoring wetland water quality on time. And this work reveals artificial wetland has the effect to improve water quality.
Li, Wen. „Mechanisms for phosphorus elimination in constructed wetlands: a pilot study for the treatment of agricultural drainage water from dairy farms at the Lower River Murray, South Australia / Li Wen“. 2002. http://hdl.handle.net/2440/21868.
Der volle Inhalt der QuelleBibliography: leaves 176-197.
iii, ix, 197, [22] leaves : ill., maps ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Phosphorus retention was measured in five pilot-scaled constructed wetlands with different configurations in terms of macrophyte species and substrates in order to evaluate the phosphorus removal efficiency of water plants and substrates in experimental ponds; assess the contribution of macrophytes to phosphorus removal through direct uptake, modification of water chemistry and impacts on the phosphorus adsorption characteristics of substrate; and, contribute to the optimal design and operation of constructed wetlands for the treatment of agricultural drainage water.
Thesis (Ph.D.)--University of Adelaide, Dept. of Soil and Water, 2002?
Pete, Kwena Yvonne. „Photocatalytic degradation of dyes and pesticides in the presence of ions“. Thesis, 2015. http://hdl.handle.net/10352/308.
Der volle Inhalt der QuelleWater pollution caused by organic and inorganic contaminants represents an important ecological and health hazard. Simultaneous treatment of organic and inorganic contaminants had gradually gained great scientific interest. Advanced oxidation processes such as photocatalysis, using TiO2 as a photocatalyst, have been shown to be very robust in the removal of biorecalcitrant pollutants. These methods offer the advantage of removing the pollutants, in contrast to conventional techniques. At present, the main technical challenge that hinder its commercialization remained on the post-recovery of the photocatalyst particles after water treatment. Supporting of the photocatalyst on the adsorbent surface is important as it assists during the filtration step, reducing losses of the materials and yielding better results in degrading pollutants. To overcome this challenge, in this study composite photocatalysts of TiO2/zeolite and TiO2/silica were prepared and investigated to explore the possible application in the simultaneous removal of organic and inorganic compounds from contaminated water. The main objective of this study was to investigate the heterogeneous photocatalytic degradation of organic compounds in the presence of metal ions using composite photocatalysts. The Brunauer–Emmett–Teller (BET), Scanning Electron Microscopy and Energy Dispersive X-ray (SEM-EDX), Raman spectroscopy (RS) and zeta potential (ZP) analyses were used to characterize the prepared composite photocatalysts. The successive composite photocatalysts were used in a semi-batch reactor under an irradiation intensity of 5.5 mW/m2 (protected by a quartz sleeve) at 25 ± 3°C for the photocatalytic degradation of synthetic textile (methyl orange) and agricultural (atrazine) wastewater in the presence of ions. The effect of operating parameters such as TiO2 composition on supporting material, particle size, composite photocatalyst loading, initial pollutant concentration and pH were optimized. The effects of inorganic salts and humic acid on dye and pesticides degradation were also studied, respectively. The performance of the photocatalyst reactor was evaluated on the basis of color removal, metal ion reduction, total organic carbon (TOC) reduction, intermediates product analysis and modeling of kinetics and isotherms. Different kinetic and isotherm models were introduced and applied in this work. Important aspects such as error functions with the optimal magnitude were used for the selection of the best suitable model.
European Union. City of Mikkeli, Finland. Water Research Commission (RSA)
Foureaux, Nathalia Silva. „Monitoring of 17B-estradiol in raw and treated samples of wastewater treatment plants“. Master's thesis, 2021. http://hdl.handle.net/10198/23799.
Der volle Inhalt der QuelleAquatic environment pollution is a keen subject in the most important discussions surrounding global issues. With the increase of industrialization, globalization and urbanization, as consequence, there is an increase in production of high-level pollutants. Emerging pollutants (EP’s) are compounds which are, usually, not found in natural water sources. Data concerning the occurrence and concentrations of some pharmaceuticals in effluents from WWTPs and surface waters, shows that EP concentrations in effluents fluctuate widely, most probably due to inconsistent efficiency of wastewater treatment. Endocrine disrupting compounds (EDCs), are an important group of EP’s, considering they are often found in different aquatic matrices. Nowadays, monitoring the concentration levels of estrogens in treated wastewaters of wastewater treatment plants (WWTP) is an environmental mandatory task to minimize or eliminate water pollution. The present work is divided in two main experimental stages. First, an SPE/HPLC-UV experimental methodology is optimized to detect and quantify 17β-Estradiol (E2) present in aqueous samples. The HPLC-UV operating conditions were selected by performing a screening between 10 different mobile phase compositions. A pure methanol composition was selected based in the lower retention time and the highest UV detector signal. The solid phase extraction optimization involves a three-level Box-Behnken experimental design with four factors (sample volume, sample pH, adsorbent drying time and solvent composition used for the washing step), combined with a response surface methodology. The implementation of the optimized experimental methodology occurred by the monitoring of estradiol in a wastewater influent and effluent samples. E2 was detected and quantified in three different samples collected from three distinct point of a WWTP. Sample 1 was collected from the entrance point, sample 2 was collected from the activated sludge aeration tank and sample 3 was the completely treated effluent. The concentration of E2 found in three points was higher than what was anticipated, but coherent with other works.
A poluição do ambiente aquático é um assunto importante nas discussões mais importantes em torno de questões globais. Com o aumento da industrialização, globalização e urbanização, como consequência, há um aumento na produção de poluentes de alto nível. Poluentes emergentes (PE) são compostos que, geralmente, não são encontrados em fontes naturais de água. Dados relativos à ocorrência e concentração de alguns produtos farmacêuticos em efluentes de ETARs e águas superficiais, mostram que as concentrações de PE em efluentes variam amplamente, muito provavelmente devido à eficiência inconsistente do tratamento de águas residuais. Compostos desreguladores endócrinos (CDEs), são um importante grupo de PE, considerando que são freqüentemente encontrados em diferentes matrizes aquáticas. Atualmente, monitorar os níveis de concentração de estrogênios em águas residuárias tratadas de estações de tratamento de efluentes (ETE) é uma tarefa ambiental de suma importância para minimizar ou eliminar a poluição da água. O presente trabalho está dividido em duas etapas experimentais principais. Primeiro, uma metodologia experimental SPE/HPLC-UV é otimizada para detectar e quantificar o 17β-estradiol (E2) presente em amostras aquosas. As condições operacionais de HPLC-UV foram selecionadas realizando uma triagem entre 10 composições de fase móvel diferentes. Uma composição de metanol puro foi selecionada com base no menor tempo de retenção e no maior sinal do detector de UV. A otimização da extração em fase sólida envolve um projeto experimental Box-Behnken de três níveis com quatro fatores (volume da amostra, pH da amostra, tempo de secagem do adsorvente e composição do solvente usado para a etapa de lavagem), combinado com uma metodologia de superfície de resposta. A implementação da metodologia experimental otimizada ocorreu por meio do monitoramento do estradiol em uma amostra de efluente e afluente de água residuária. O E2 foi detectado e quantificado em três diferentes amostras coletadas em três pontos distintos de uma ETAR. A amostra 1 foi coletada do ponto de entrada, a amostra 2 foi coletada do tanque de aeração de lodo ativado e a amostra 3 foi o efluente completamente tratado. A concentração de E2 encontrada em três pontos foi maior do que o previsto, mas coerente com outros trabalhos.
Tavares, Joana Filipa da Costa. „Economic analysis of pharmaceutical water pollution abatement in nursing home effluents“. Master's thesis, 2019. http://hdl.handle.net/10071/21376.
Der volle Inhalt der QuelleOs produtos farmacêuticos têm sido detetados em águas superficiais e subterrâneas, e mesmo até em água potável. Embora as concentrações detetadas sejam geralmente baixas, os impactos nos organismos aquáticos e na saúde humana constituem motivo de preocupação. Há uma tendência para estes riscos aumentarem devido ao uso crescente de medicamentos, assim como do reaproveitamento de água. De um ponto de vista económico, a poluição é um exemplo de uma falha de mercado que pode (e deve) ser corrigida através de intervenção governamental, contudo a poluição das águas com produtos farmacêuticos é particularmente difícil de regulamentar uma vez que o consumo de medicamentos é crucial em termos de saúde. Uma das alternativas é investir em soluções em que o foco é reduzir o impacto do consumo de medicamentos através da sua remoção das águas residuais antes da descarga no meio ambiente. Este trabalho sintetiza o conhecimento acerca da poluição das águas com produtos farmacêuticos e apresenta uma análise custo-benefício de dois novos tipos de filtros numa escala piloto, um solar e outro que combina um biorreator de membrana com foto-oxidação. A análise é aplicada a lares de idosos em França, Espanha e Portugal. Os custos incluem o investimento (equipamento e montagem) e custos operacionais (energia, químicos, manutenção e substituição de equipamento), os benefícios baseiam-se no preço sombra que difere consoante as águas residuais são descarregadas em áreas sensíveis ou não sensíveis. O valor atual líquido varia consideravelmente consoante o filtro piloto, o país e o destino das águas residuais.
Vertonha, Maria Thais. „Valorization of leached waters through conversion in liquid fertilizers“. Master's thesis, 2018. http://hdl.handle.net/10198/21034.
Der volle Inhalt der QuelleAn unprecedented demographic explosion occurred in the last decades at a global level. The negative impacts of this event stand out, affecting the social, economic and mainly environmental spheres. In the environmental aspect, an important consequence is the growing production of solid wastes, due partially to the population increase. However, the development of effective technologies for the treatment of these wastes did not accompany such growth, and currently the most used method for this is landfill disposal. Even with the possibility of alternatives, the use of landfills for the disposal of solid wastes will be necessary over a long period, with the inevitable consequence of the generation of leachate streams. The objective of this work is the development, design and implementation of processes for physicochemical conversion of leachate liquid effluents from a composting process in liquid fertilizers with a standardized and reproducible composition. The leachate sample was collected in February 2019 from the slurry storage tank of the company “Resíduos do Nordeste”, EIM (Urjais, Mirandela, Portugal). The stream is produced and recovered from a composting line from a mechanical and biological waste treatment plant. From this original sample, three additional materials were obtained: a filtered sample for the removal of the solid fraction (Filtro 03/04), two concentrated samples by simple distillation, with two concentration levels in volume basis: 1,19x and 1,85x in relation to the original leachate sample. The four samples (the original leachate and the three processed samples) were submitted to a sequence of analyzes, in order to compare its composition and properties with the current Portuguese and European legislation specifications for liquid fertilizers. The selected characterization parameters were: Total Organic Carbon (TOC), pH, Conductivity, Percentage of Dry Matter, Density, and Heavy Metals, Phosphorus, Potassium and Nitrogen contents. Adsorption tests were performed with the Filter 03/04 sample, with two adsorbents of different origin, the first produced from an organic compound, resulting from a centralized composting process, obtained from the same landfill that provided the Original sample. The second adsorbent tested is activated clays, originating from four different deposits in Kazakhstan. After treatment with the adsorbents, the same analyzes were performed previously, aiming to evaluate the efficiency of the adsorbents. The characterization results were then used to verify the framework for later use of the original leachate and/or the processed samples as liquid organomineral fertilizers, and to assess the specific needs of composition tuning for the non-processed leachate sample. A concentration process for the original sample of 1,19x (v/v) has been determined to allow the reaching of at least 3% TOC, a content legally required. Additionally, treatment is required for the removal of nickel and chromium from the samples. The metals zinc, copper, cadmium and lead have been quantified and are within the limits specified in the Regulation of the European Parliament and of the Council (2019). A flowchart for the proper treatment of this leachate was proposed, with the intention of using it as liquid organomineral fertilizer.
Uma explosão demográfica sem precedentes ocorreu nas últimas décadas a nível global. Destacam-se os impactos negativos deste evento, afetando as esferas social, econômica e principalmente ambiental. No aspeto ambiental, uma consequência importante é a crescente produção de resíduos sólidos, em parte devido ao aumento populacional. No entanto, o desenvolvimento de tecnologias eficazes para o tratamento desses resíduos não acompanhou esse crescimento, e atualmente o método mais utilizado para isso é o descarte em aterros sanitários. Mesmo com a possibilidade de alternativas, o uso de aterros sanitários para a disposição de resíduos sólidos será necessário por um longo período, com a inevitável consequência da geração de caudais de chorume. O objetivo deste trabalho é o desenvolvimento, proposta e implementação de processos de conversão físico-química de efluentes líquidos lixiviados, de um processo de compostagem, em fertilizantes líquidos com uma composição padronizada e reprodutível. A amostra de lixiviados foi coletada em fevereiro de 2019 a partir do tanque de armazenamento de chorume da empresa “Resíduos do Nordeste”, EIM (Urjais, Mirandela, Portugal). O fluxo é produzido e recuperado de uma linha de compostagem de uma estação de tratamento de resíduos mecânica e biológica. Desta amostra original, três materiais adicionais foram obtidos: uma amostra filtrada para a remoção da fração sólida (Filtro 03/04), duas amostras concentradas por destilação simples, com dois níveis de concentração em base volumétrica: 1,19x e 1,85x em relação a amostra original. As quatro amostras (o lixiviado original e as três amostras processadas) foram submetidas a uma sequência de análises, de modo a comparar a sua composição e propriedades com as atuais especificações da legislação portuguesa e europeia para fertilizantes líquidos. Os parâmetros de caracterização selecionados foram: teor de carbono orgânico total (TOC), pH, condutividade elétrica, percentagem de matéria seca, densidade e metais pesados, fósforo, potássio e nitrogênio. Foram realizados testes de adsorção com a amostra Filtro 03/04, com dois adsorventes de origem diferente, o primeiro produzido a partir de um composto orgânico, resultante de um processo de compostagem centralizada, obtido do mesmo aterro sanitário que forneceu a amostra Original. O segundo adsorvente testado, são as argilas ativadas, originárias de quatro depósitos diferentes do Cazaquistão. Após o tratamento com os adsorventes foram realizadas as mesmas análises feitas anteriormente, com o objetivo de avaliar a eficiência dos adsorventes. Os resultados da caracterização foram então utilizados para verificar a estrutura para posterior utilização do lixiviado original e/ou as amostras processadas como fertilizantes organominerais líquidos, e para avaliar as necessidades específicas de ajuste da composição. Um processo de concentração para a amostra original de 1,19x (v/v) foi determinado para permitir o alcance de pelo menos 3% de TOC, um conteúdo legalmente requerido no Regulamento do Parlamento Europeu e do Concelho (2019). Além disso, é necessário um tratamento para a remoção de níquel e cromio das amostras. Os metais zinco, cobre, cádmio e chumbo foram quantificados e estão dentro dos limites especificados no Regulamento do Parlamento Europeu e do Conselho (2019). Um fluxograma para o tratamento adequado desse lixiviado foi proposto, com o intuito de utilizá-lo como fertilizante organomineral líquido.
This work was carried out under the scope of Project VALORCOMP, funded by FEDER through Programme INTERREG V-A Spain − Portugal (POCTEP) 2014–2020. Finally, to all who have somehow been part of this period and collaborated to carry out this work, I will be eternally grateful.
Rödlová, Sylva. „Změna kvality vody v malých povodích po postavení čistírny odpadních vod“. Doctoral thesis, 2010. http://www.nusl.cz/ntk/nusl-299194.
Der volle Inhalt der QuelleMarques, Vitor da Costa. „Valorization of tangerine peels in the preparation of adsorbents for removal of Ni(II) from aqueous solutions“. Master's thesis, 2018. http://hdl.handle.net/10198/22626.
Der volle Inhalt der QuelleThe discharge of industrial and domestic wastewater is one of the main causes of contamination of water bodies by heavy metals. Among these heavy metals, nickel (Ni) is one of the most used in industrial processes, such as the production of alloys, stainless steel and automotive batteries, as well as electroplating activities, causing high concentrations in the effluents of these industries. Several techniques, such as chemical precipitation and filtration, have been studied in order to promote the removal of these heavy metals from wastewater. However, these techniques are often financially and technically costly. Under this context, adsorption using activated carbons (ACs) appears as an alternative, which is characterized by being an effective and economically viable technique. Citrus fruits, such as tangerine, are of great importance in the Portuguese economic context. In 2017, just over 374.4 thousand tons were produced, with 10% of this volume corresponding to tangerine. This research aimed, therefore, to produce ACs from tangerine peels and use them in the adsorption of nickel from aqueous medium. The ACs were produced in two stages: activation and carbonization. Upon activation, the hydrothermal carbonization process (HTC) was used considering FeCl3 as activating agent under three concentrations (0.5, 1.0 and 2.5 M). Afterwards, the prepared materials were carbonized in a tubular oven at 800 ºC for 4 h. The samples were named as follows: TW-C (pyrolyzed peels without HTC), TW-Fe-0.5-C / TW-Fe-1.0-C / TW-Fe-2.5-C (HTC and pyrolyzed peels) and TW-Fe-2.5 (peels with HTC without pyrolysis). The physico-chemical properties of the ACs, such as elemental analysis, ash content, acidity and basicity, were determined to correlate with their performance. The kinetic and isotherm adsorption of Ni(II) onto the ACs was assessed at the following operating conditions: 2.5 g L-1 of AC, 25 ºC and pH 6 and modelled by the kinetic models of pseudo-first order, pseudo-second order and Elovich, as well as the adsorption isotherms of Langmuir, Freundlich and the General Isotherm Equation (GIE) of Tóth. The materials TW-C showed the best adsorption results and removed 99% of Ni(II) at pH 9. The kinetic models that best described the adsorption process were pseudo-second order (TW-Fe-2.5-C) and Elovich (TW-C). The GIE of Tóth showed the best fit, however, its parameters did not show statistical significance at the 5% confidence level, being rejected. The Freundlich model was able to represent the experimental data with certain precision (R² reached 0.9557 and 0.9785 for TW-C and TW-Fe-2.5-C, respectively) and statistical significance according to the t-test and F-test.
A descarga de águas residuais industriais e domésticas é uma das principais causas de contaminação de corpos d'água por metais pesados. Entre esses metais pesados, o níquel (Ni) é um dos mais utilizados em processos industriais, como na produção de ligas metálicas, aço inoxidável e baterias de automóveis, bem como na galvanoplastia, originando altas concentrações nos efluentes dessas indústrias. Várias técnicas, como precipitação química e filtração, foram estudadas para promover a remoção desses metais pesados de águas residuais. No entanto, essas técnicas são financeiramente e tecnicamente caras. Como alternativa surge a adsorção utilizando carvão ativado (AC), caracterizada por ser uma técnica eficaz e economicamente viável. Os citrinos, como a tangerina, apresentam relevada importância no contexto económico português. No ano de 2017 foram produzidas pouco mais de 374,4 mil toneladas, onde 10% desse volume correspondeu a tangerina. Tendo este enquadramento em consideração, este trabalho objetivou produzir ACs a partir de cascas de tangerina para aplicação na adsorção de níquel presente em meio aquoso. Os ACs foram produzidos em duas etapas: Ativação e Carbonização. Na ativação foi usado o processo de carbonização hidrotérmica (HTC) considerando FeCl3 como agente ativante em três concentrações (0,5; 1,0 e 2,5 M); posteriormente, os materiais preparados foram carbonizados em forno tubular a 800 ºC por 4 h. As amostras foram nomeadas da seguinte forma: TW-C (cascas pirolisadas sem HTC), TW-Fe-0,5-C / TW-Fe-1,0-C / TW-Fe-2,5-C (HTC e cascas pirolisadas) e TW-Fe-2,5 (cascas com HTC sem pirólise). As propriedades físico-químicas dos ACs foram determinadas por análise elementar, teor de cinzas, acidez e basicidade, para correlacionação com o seu desempenho no processo de adsorção. A cinética de adsorção e isotérmicas de adsorção de Ni(II) nos ACs foi avaliada nas seguintes condições operacionais: 2,5 g L-1 de AC, 25 ºC e pH 6, aplicando os modelos cinéticos de pseudo-primeira ordem, pseudo-segunda ordem e Elovich, bem como as isotérmicas de adsorção de Langmuir, Freundlich e a Equação Geral da Isotérmica (GIE) de Tóth. O carvão TW-C apresentou os melhores resultados de adsorção e removeu 99% de Ni(II) a pH 9. Os modelos cinéticos que melhor descreveram o processo de adsorção foram o de pseudo-segunda ordem (TW-Fe-2.5-C) e Elovich (TW-C). O GIE de Tóth apresentou o melhor ajuste, no entanto, os seus parâmetros não apresentaram significância estatística no nível de confiança de 5%, sendo rejeitado. O modelo de Freundlich foi capaz de representar os dados experimentais com certa precisão (R² atingiu 0,9557 e 0,9785 para TW-C e TW-Fe-2,5-C, respectivamente) e significância estatística de acordo com o teste t e o teste F.
First of all, I would like to thank my parents, Edson and Claudete, without whom I would not be given so many opportunities, I thank you for the support and encouragement during all these years of graduation and for sharing with me the challenges and difficulties faced away from home. I thank my brother for the partnership, complicity, for being present even with the distance. I thank my friends Pedro and Larissa, for their support during this stage and for their friendship over the years. To my supervisor, teacher and friend Tatiane, for all the help, advice and opportunities during the undergraduate years and later with the master's degree. I am grateful to my co-supervisor José, who was fundamental in the execution of this work and for whom I learned to cultivate respect and admiration. I thank my supervisor, Professor Helder, for the opportunity and confidence. My laboratory friends Fernanda, Adriano and Gabriel, who shared their knowledge and helped me with the execution of my practical work. I thank Maria João, technician at the Chemical Process Laboratory, for being helpful and patient. I would like to thank Professor Margarida and the Mountain Research Center (CIMO) for their assistance with my analysis. I am grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020).