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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Kauno rajono buitinių atliekų sąvartyne susidarančio filtrato įtakos vandenų kokybei analizė / Analysis of Influence to Water Quality Made by Filtrate of Landfills in Kaunas district

Venslavičiūtė, Ligita 14 January 2009 (has links)
Sąvartynai – pasaulinė problema. Daugelyje Vakarų Europos šalių sąvartynų tyrimai atliekami jau ne vieną dešimtmetį, kai Lietuvoje juos pradėta tirti tiktai atkūrus nepriklausomybę, todėl duomenys apie sąvartynus nėra gausūs, tačiau Lietuvoje yra pakankama teisinė bazė atliekų tvarkymo srityje. Teisės aktais nurodyti reikalavimai sąvartynų įrengimui, eksploatacijai ir uždarymui. Analizei atlikti surinkta informacija apie buitinių atliekų sąvartyną, kuris yra Kauno rajone Lapių seniūnijoje. Gruntinio ir paviršinio upelių vandens cheminę sudėtį ir atskirų komponentų koncentraciją sąvartyno aplinkoje lemia filtrato ir pramoninių tirpalų patekimas į gruntą ir jų pernešimas požeminėmis tėkmėmis. Šiame darbe yra analizuojami 1994 – 2007 metų hidromonitoringo duomenys. Lapių sąvartynas daro didelę neigiamą žalą gruntiniam, požeminiam vandeniui, bei Marilės upeliui. Darbe analizuojami pagrindiniai vandens taršos rodikliai: BDS7, bendras azotas, bendras fosforas, chloridai, nitritai. Drenažu surenkama tik dalis filtrato, kita dalis infiltruojasi į gruntinius vandenis. Sąvartynuose susidarantis filtratas – viena aktualiausių su sąvartynais susijusių apsaugos problemų. Todėl šiame darbe atlikti Lapių sąvartyno pirmojo kaupimo lauko filtrato kiekio skaičiavimai, per metus susidaro 74645m3. Nustatyta, kad praėjus dešimčiai metų po sąvartyno uždengimo pirmojo kaupimo lauko filtrato kiekis sumažėtų iki 786 m3 per metus. Gruntinio vandens, kurį tiesiogiai veikia filtrato sklaida, cheminę... [toliau žr. visą tekstą] / Landfills are a world wide problem. In most of Western European countries landfills have been investigated for many years, whereas in Lithuania the investigations of the landfills started only after restoring the Independence. That is why the facts about landfills are not numerous, but Lithuania has a rather good juristical base in the sphere of waste treatment.The acts/documents of law indicate the requirements for the dump equipment, maintenance and closing. In order to evaluate the situation, the information about the landfill of waste which is in Kaunas region, in Lapės, was collected. The chemical composition of the stream groundwater and surface-water and the concentration of separate components in the surroundings of the landfill are conditioned by leachate and industrial leach which gets/falls into the ground and is carried with the help of underwater. The data of hidromonitoring of the year 1994 – 2007 are analysed in this paper. The landfill of Lapės pollute the groundwater and the Marilės stream. The main indicators of the water pollution are analysed in the paper biochemical oxygen demand, total nitrogen, total phosphorus, chlorides, nitrites. Drainage collects only one part of the leachate, and the other part is infiltrated into groundwater. The leachate which is formed in the landfill is one of the most relevant and connected with landfills environmental problems. That is why the calculations of the leachate amount in the first storage field of Lapės landfill... [to full text]
152

Sąvartyno filtrato savybių eksperimentiniai tyrimai ir jas veikiančių sąlygų įvertinimas / Landfill leachate characteristics of experimental studies and their assessment of the condition affecting

Kačinskaja, Irina 21 June 2013 (has links)
Baigiamajame magistro darbe nagrinėjamos komunalinių atliekų sąvartynų keliamos aplinkosaugos problemos. Pagrindinė problema – filtrato susidarymas. Pirmajame skyriuje išnagrinėti savartyno filtrato savybių tyrimai, atlitki kitų mokslininkų Lietuvoje ir užsienyje, aptarta filtrato keliama žala dirvožemiui ir gruntiniams vandenims, išskirta kolmatacijos problema. Taip pat aprašytos sąvartynų filtrato valymo technologijos. Antrojo skyriaus pirmame poskyryje pateikta eksperimentų metodika. Darbe atlikti skendinčiųjų medžiagų, kalcio, magnio, bendrosios organinės anglies (TOC) koncentracijų, pH kitimo eksperimentiniai tyrimai per 12 savaičių. Antrajame antro skyriaus poskyryje išnagrinėti gauti eksperimentų rezultatai, išanalizuotas tirtųjų savybių kitimas ir pastarojo priežastys bei pateiktos poskyrio išvados. Trečiajame skyriuje atliktas sąvartyno filtrato keliamos taršos prognozavimas naudojantis Microsoft Excel skaičiuokle. Darbo pabaigoje pateikiamosa bendrosios išvados, rekomendacijos, literatūros ir autoriaus publikacijų sąrašas. Darbą sudaro 6 dalys: įvadas, 3 skyriai, išvados ir siūlymai, literatūros sąrašas. Darbo apimtis – 90 p. teksto be priedų, 52 iliustr., 14 lent., 91 literatūros šaltinis. / The thesis examines municipal waste landfills pose environmental problems. The main problem - leachate generation. In the first section examine the characteristics of the landfill leachate studies conducted by other researchers in Lithuania and abroad, discussed the filtrate caused damage to the soil and groundwater derived kolmatacijos problem. Also described in landfill leachate treatment technologies. Second the first subsection of the experimental methodology. The work carried out suspended solids, calcium, magnesium, total organic carbon (TOC) concentrations, pH variation of experimental studies of 12 weeks. In the second section of the second chapter to consider to get the results of the experiments, analyzed the changes in properties of the latter, and the reasons for the conclusions section. The third chapter reviews the municipal waste landfill leachate collection system life prediction Microsoft Excel spreadsheets. At the end of the general conclusions, and the author's list of publications. Structure: introduction,3 chapters, conclusions and suggestions, references. Thesis consist of: 80 p. text without appendixes, 52 pictures, 14 tables, 91 bibliographical entries.
153

Ageing of HDPE Geomembranes Used to Contain Landfill Leachate or Hydrocarbon Spills

Rimal, SANTOSH 14 January 2009 (has links)
The ageing of high density polyethylene geomembrane (GM) liners used to minimize advection and diffusion of contaminants in municipal solid waste landfill leachate and in hydrocarbon spills to the environment is examined. The evaluation of the ageing of GMs used in landfills involved four components. First, a laboratory-accelerated ageing investigation of a GM exposed to air, water and leachate at elevated temperatures. Service life of a GM (Stage I: Antioxidant depletion, Stage II: Induction, and Stage III: Polymer degradation) is examined. The results demonstrate the critical role of antioxidants in protecting against oxidative degradation. The service life of the GM is predicted. Second, a study was conducted to provide an estimate of Stage I for a GM in a composite liner. The results indicated that immersion tests are too severe and the service life is substantially greater for a GM in composite liner than implied by leachate immersion tests. Third, a comparison of ageing with three different “protection” layers between the GM and overlying gravel and leachate is reported. A slower antioxidant depletion rate is observed when geotextile-geosynthetic clay liner and geotextile-sand-geotextile are applied than with a typical geotextile alone. This could be partially attributed to the attenuation of leachate constituents by the protection layer as well as the buildup of antioxidant concentration on either side of GM thereby reducing the concentration gradient and outward diffusive flux of antioxidants. Fourth, diffusion modelling is used to evaluate the results from immersion and composite liner simulation tests. Diffusion modelling provided a means for predicting the performance of the GMs in conditions other than the typical test conditions. The evaluation of the ageing of GM used in barrier system for hydrocarbon involved two components. First, untreated and fluorinated GMs immersed in jet fuel were tested. Results show that antioxidants depleted at slower rate from fluorinated GM than untreated GM. This suggested a significant beneficial effect of fluorination. Antioxidant depletion time is predicted at field temperatures. Second, the time dependant change in GM samples used at jet fuel containment site constructed in 2001 is reported. The GM is shown to be performing very well. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-01-14 10:46:31.089
154

Denitrification of high strength nitrified landfill leachate using raw and lightly composted commercial garden refuse (CGR) as carbon sources.

Zondi, Mzamoyendoda Samuel. 23 September 2013 (has links)
Waste is commonly disposed in landfills, this result in the formation of leachate which needs to be treated to acceptable standards before being discharged to the environment. High concentrations of pollutants, particularly ammonia, in the landfill leachate are persistent even after the closure of the landfill and it requires ad hoc treatment. Treated leachate can still be characterized by high concentrations of nitrates, which exceeds the discharge standards. This phenomenon is observed in the Mariannhill landfill site in Durban, where leachate is nitrified in a Sequencing batch reactor and produces effluent with over 1000 mg/l (Trois et al, 2010a). Denitrification can be used to remove nitrate concentrations, this process occurs under anoxic conditions in the presence of an external carbon source. Denitrification treatment methods utilize chemicals such as methanol and ethanol as carbon sources, but the large scale application of these chemicals is often uneconomical. This research aims at identifying the cost effective treatment system for bio-denitrification that utilizes commercial garden refuse (CGR raw and lightly composted for 10 weeks “CGR 10”) as carbon sources. The feasibility checks for applying these substrates were based on the efficiency and kinetics of nitrate removal over a short and long-term period, thus providing the estimates for operational procedures. Initial characterization tests, batch and column tests were performed in the lab towards achieving the aim of this research. All batch tests achieved 100% of nitrate removal, but CGR raw was faster than CGR 10 with a time difference of 16% and 20% for batches at 100 and 500 mg/L, respectively. The significant difference in the kinetic removal efficiency was observed in batch tests at 2000 mg/L, where CGR raw was about 18 times faster than CGR 10 and about 2 times faster than that of CGR raw at 500 mg/L. Thus, the kinetics of nitrate removal in CGR raw at 2000 mg/L was suspected to be due to chemical reaction other than biological reaction. In the second set of batch tests the kinetics of nitrate removal for CGR raw was about 3 times that of CGR 10. The column tests, which were operated as continuous flow reactor did not achieve full denitrification due to high flow rate applied. First set of column tests (columns A) used previously used substrates to treat synthetic nitrate solution (500 and 2000 mg/L). Second set of column tests (columns B) used fresh substrates to treat pre-treated landfill leachate with nitrate concentration of about 2000 mg/L. CGR 10 achieved better removal efficiency than CGR raw when treating synthetic solution. Whereas, CGR raw achieved better nitrate removal when treating pre-treated landfill leachate. Decrease in flow rate improved the removal efficiency of the substrates. Dilution of nitrified leachate to about 500 mg/L could improve the efficiency of the substrates. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2011.
155

A Novel Computational Approach for the Management of Bioreactor Landfills

Abdallah, Mohamed E. S. M. 13 October 2011 (has links)
The bioreactor landfill is an emerging concept for solid waste management that has gained significant attention in the last decade. This technology employs specific operational practices to enhance the microbial decomposition processes in landfills. However, the unsupervised management and lack of operational guidelines for the bioreactor landfill, specifically leachate manipulation and recirculation processes, usually results in less than optimal system performance. Therefore, these limitations have led to the development of SMART (Sensor-based Monitoring and Remote-control Technology), an expert control system that utilizes real-time monitoring of key system parameters in the management of bioreactor landfills. SMART replaces conventional open-loop control with a feedback control system that aids the human operator in making decisions and managing complex control issues. The target from this control system is to provide optimum conditions for the biodegradation of the refuse, and also, to enhance the performance of the bioreactor in terms of biogas generation. SMART includes multiple cascading logic controllers and mathematical calculations through which the quantity and quality of the recirculated solution are determined. The expert system computes the required quantities of leachate, buffer, supplemental water, and nutritional amendments in order to provide the bioreactor landfill microbial consortia with their optimum growth requirements. Soft computational methods, particularly fuzzy logic, were incorporated in the logic controllers of SMART so as to accommodate the uncertainty, complexity, and nonlinearity of the bioreactor landfill processes. Fuzzy logic was used to solve complex operational issues in the control program of SMART including: (1) identify the current operational phase of the bioreactor landfill based on quantifiable parameters of the leachate generated and biogas produced, (2) evaluate the toxicological status of the leachate based on certain parameters that directly contribute to or indirectly indicates bacterial inhibition, and (3) predict biogas generation rates based on the operational phase, leachate recirculation, and sludge addition. The later fuzzy logic model was upgraded to a hybrid model that employed the learning algorithm of artificial neural networks to optimize the model parameters. SMART was applied to a pilot-scale bioreactor landfill prototype that incorporated the hardware components (sensors, communication devices, and control elements) and the software components (user interface and control program) of the system. During a one-year monitoring period, the feasibility and effectiveness of the SMART system were evaluated in terms of multiple leachate, biogas, and waste parameters. In addition, leachate heating was evaluated as a potential temperature control tool in bioreactor landfills. The pilot-scale implementation of SMART demonstrated the applicability of the system. SMART led to a significant improvement in the overall performance of the BL in terms of methane production and leachate stabilization. Temperature control via recirculation of heated leachate achieved high degradation rates of organic matter and improved the methanogenic activity.
156

Étude des composés chimiques extraits des lixiviats issus de la thermotransformation du pin gris (Pinus banksiana Lamb.) /

Ross, Josette, January 1900 (has links)
Thèse (M.Ress.Renouv.) -- Université du Québec à Chicoutimi, 2005. / Bibliogr.: f. 62-66. Document électronique également accessible en format PDF. CaQCU
157

Recuperação do íon amônio gerado durante a evaporação de lixiviados de aterros utilizando resinas poliméricas de troca iônica / Recovery of ammonium ion generated during the evaporation of landfill leachate using polymeric ion exchange resins

Jackeline Maria Cardoso de França Bahé 17 December 2014 (has links)
O lixiviado gerado em aterro sanitário possui substâncias de difícil degradação e amônia, que dificulta o tratamento biológico. O tratamento do lixiviado gerado em aterros sanitários requer uma série de processos de elevado custo e, outras técnicas de tratamento têm sido investigadas no intuito de reduzir custos e aumentar a eficiência do tratamento. A evaporação do lixiviado é uma técnica que aproveita o gás de aterro como fonte de calor, e é utilizada na redução do volume a tratar; porém as emissões atmosféricas geradas durante essa evaporação indicam a presença de amônia, o que pode causar impactos negativos em torno do aterro. Desta forma, é importante a realização de estudos que aprimorem esta técnica, para que a evaporação torne-se ambientalmente e economicamente viável. A amônia presente em amostras com pH em torno de 8,0 e temperatura em torno de 25C, está na forma de íon amônio, o que favorece ao processo de troca iônica. A troca iônica é um processo que tem sido estudado por muitos pesquisadores e consiste na troca de um ou mais constituintes de uma fase fluida para a superfície de uma fase sólida (resinas poliméricas). Este trabalho apresenta a eficiência de quatro tipos diferentes de resinas poliméricas: Amberlyst 15 Wet, Lewatit VPOC 1800, Dowex Mac-3 e Purolite MN250 na remoção e posterior, recuperação do íon amônio presente nos vapores condensados da evaporação de lixiviados. A princípio foi investigado a quantidade e o momento em que o amônio é lançado durante o processo de evaporação. Em seguida, caracterizaram-se as resinas quanto à eficiência de remoção, o tempo de contato e a quantidade ideal da resina. Estão apresentadas neste estudo as isotermas de adsorção de Langmuir, Freundlich e Temkin em diferentes temperaturas (298-318 K) e as condições ideais do processo. Os resultados apontaram duas resinas com eficiência de remoção, em torno de 40%, para concentrações acima de 1000 mg dm-3 de amônio, utilizando 0,5 g de resina e um tempo de contato de 20 minutos. Diferentes modelos cinéticos foram aplicados: Pseudo-Primeira Ordem, Pseudo-Segunda Ordem, difusão intrapartícula, Elovich e o modelo cinético de difusão externa e os resultados discutidos. Foi possível tratar Através da condensação dos vapores emitidos durante a evaporação do lixiviado, foi possível tratar foi possível obter uma recuperação em torno de 70% do íon amônio contido no vapor condensado proveniente da evaporação do lixiviado. / The leachate generated at the landfill has substances are difficult to degrade and ammonia, which hinders the biological treatment. The treatment of the leachate generated in landfills requires a number of high-cost procedures and other treatment techniques have been investigated in order to reduce costs and increase the efficiency of treatment. Evaporation of leachate is a technique that takes advantage of landfill gas as a heat source , and is used in reducing the volume to be treated, but atmospheric emissions generated during this evaporation indicate the presence of ammonia, which can cause negative impact on the surrounding the landfill. Thus, it is important to conduct studies that will improve this technique, so that evaporation to become environmentally and economically viable. The present in samples with pH around 8.0 and temperature around 25 C, ammonia is in the form of ammonium ion, which favors the ion exchange process. Ion exchange is a process that has been studied by many researchers and consists of the exchange of one or more constituents of a fluid phase to the surface of a solid phase ( polymer resin ). This paper shows the efficiency of four different types of polymeric resins: Amberlyst 15 Wet, Lewatit VPOC 1800 Dowex Mac - 3 and Purolite MN250 removal and later, recovery of ammonium ion present in the vapor condensate evaporation of leachate. At first it was investigated how much and when ammonium is released during the evaporation process. Then, the resins were characterized as to the removal efficiency, the contact time and the optimum amount of the resin. Are presented in this study, adsorption isotherms of Langmuir, Freundlich and Temkin at different temperatures (298-318 K) and the optimal process conditions. The results showed two resins with removal efficiency of around 40% for concentrations above 1000 mg dm-3 ammonium, using 0.5 g of resin and a contact time of 20 minutes. Different kinetic models were applied: pseudo-first order , pseudo-second order, intraparticle diffusion and Elovich kinetic model of external diffusion and results discussed. It can be treated by the condensation of the vapors emitted during the evaporation of the leachate was possible to treat it was possible to obtain a recovery of around 70% of the ammonium ion contained in the condensed steam from the evaporation of leachate.
158

Avaliação da recalcitrância e toxicidade de lixiviado bruto e tratado por processos primário e secundário. / Evaluation of recalcitrance and toxicity of raw leachate and treated by primary and secondary processes.

Caroline Mitai Marques Pereira 10 April 2013 (has links)
Financiadora de Estudos e Projetos / Um dos grandes problemas enfrentados no tratamento de lixiviado é a definição de suas características físico-químicas e biológicas. Neste contexto, o objetivo do presente trabalho é avaliar a composição química, a recalcitrância, e a toxicidade do lixiviado bruto e tratado por processos de tratamento (físico-químico e biológico) oriundo do Aterro Metropolitano de Gramacho, localizado no município de Duque de Caxias, no estado do Rio de Janeiro. Os resultados mostraram maior biodegradabilidade aeróbia no efluente físico-químico com percentuais variando de 7% a 35 %. A natureza de tais compostos justifica a natureza refratária do lixiviado e alerta pela toxicidade que podem atribuir tanto aos microrganismos envolvidos no processo quanto a saúde humana quando dispostos incorretamente. Para o lixiviado em estudo, observou-se a diminuição da toxicidade ao passar pelo processo físicoquímico. Dessa maneira, observou-se que é necessário a adoção de sistemas de tratamento que conjuguem processos físico-químicos atuando como pré ou pós-tratamento de processos biológicos. Sendo assim, os resultados obtidos mostram a importância deste tipo de caracterização, como fonte de subsídios para a seleção, projeto e avaliação de sistemas de tratamento. / Leachate from Municipal Solid Waste are characterized by high concentration of refractory organic matter, ammonia and toxic compounds. In this context, the objective of this study is to evaluate the chemical composition, the recalcitrance and toxicity of raw and treated leachate for treatment processes (physical and biological) from the Gramacho Metropolitan Landfill, located in the municipality of Duque de Caxias, in the state of Rio de Janeiro. The results showed higher aerobic biodegradability in the effluent physicochemical with percentages ranging from 7% to 35%. The nature of some compounds justifies the refractory nature of the leachate and alert the toxicity that can assign both the microorganisms involved in the process as human health when disposed improperly. Thus, it was observed that it is necessary to adopt treatment systems that combine physical and chemical processes acting as a propost treatment of biological processes. Thus, the results show the importance of this type of characterization, as a source of information for the selection, design and evaluation of treatment systems.
159

Tomografia elétrica aplicada na investigação de fluxo de lixiviado em meio fraturado em um lixão no município de Lavras do Sul (RS) /

Santos, Rodolfo Busolin Alves dos January 2018 (has links)
Orientador: Cesar Augusto Moreira / Resumo: A área de estudo está localizada na cidade de Lavras do Sul – RS, que é uma antiga pedreira que foi reaproveitada para a deposição dos resíduos oriundo do município. O objetivo principal é realizar o detalhamento geofísico e estrutural da contaminação do antigo lixão e correlacionar a percolação do lixiviado com as zonas fraturadas, com o uso de dois métodos de investigação (Eletrorresistividade e Polarização Induzida) e os dois arranjos (Dipolo-Dipolo e Schlumberger). Foram realizados 12 perfis de resistividade e cargabilidade na direção 45ºN, processados em 2D e 3D, e foi determinado uma possível presença de zonas de contaminação e percolação de lixiviado para fora da área do lixão. Também foi possível determinar onde estavam dispostos os resíduos sólidos e os limites do lixão, zonas fraturadas com a presença de lixiviado e zonas fraturadas com a presença de sulfetos que aprofundam até 36 m. Desde o início da operação do lixão a contaminação atingiu diversos metros de profundidade, porém com o tempo e a atenuação natural, essas zonas de fratura fecharam devido a cristalização de sulfeto. Os dois arranjos apresentaram resultados satisfatórios para os valores de resistividade. Com relação aos valores de cargabilidade, o arranjo Schlumberger apresentou melhores resultados do que o Dipolo-Dipolo. A geofísica demonstrou ser uma ferramenta importante no estudo de contaminações em rochas cristalinas, principalmente pela sua capacidade de detecção de fraturas e sua profundidade ati... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The study area is located in the city of Lavras do Sul - RS, which is an old quarry that was reused for the deposition of waste from the municipality. The main objective is to perform the geophysical and structural detailing of the contamination of the old dump and to correlate the percolation of the leachate with the fractured zones, using the two research methods (DC Resistivity and Induced Polarization) and the two arrangements (Dipole-dipole and Schlumberger). By performing 12 profiles of resistivity and chargeability in the 45ºN direction, processed in 2D and 3D, a possible presence of contamination zones and percolation of leachate outside the dump area was determined. It was also possible to determine where the solid wastes and the boundaries of the dump were located, fractured zones with the presence of leachate and fracture zones with the presence of sulfides that deepen up to 36 m. From the beginning of the operation of the dump the contamination reached several meters deep, but with time and the natural attenuation, these zones of fracture closed due to mineral neoformation of sulfide. Both arrangements presented satisfactory results for the resistivity values, in relation to the chargeability values, the Schlumberger arrangement presented better results than the Dipole-Dipole. Geophysics has been shown to be an important tool in the study of contaminations in crystalline rocks, mainly due to its ability to detect fractures and its depth. / Mestre
160

Mikroplast i behandlat lakvatten : En fallstudie med åtta avfallsanläggningar / Microplastics in treated leachate : A case study of eight waste facilities in Sweden

Eriksson Russo, Victoria January 2018 (has links)
Forskare och myndigheter runt om i världen enas idag om att stora mängder mikroplast ackumuleras i världshaven och att dessa kan tas upp av olika levande organismer. Mikroplaster definieras ofta som plastpartiklar mindre än fem millimeter och kan härstamma från olika mänskliga aktiviteter. Majoriteten av all plast som har producerats finns idag i deponier eller i naturen. Eftersom flera studier funnit att plastadditiver lakas ut ur deponier tros lakvatten från deponier vara en potentiell källa till mikroplastutsläpp. I denna studie undersöktes förekomsten av mikroplaster ≥ 100 mikrometer i behandlat lakvatten från åtta avfallsanläggningar i Sverige: sju med deponi och en utan deponi. Lakvatten från avfallsanläggningarna filtrerades genom filter med porstorlek 100 mikrometer. Partiklar på filtren inspekterades under ett stereomikroskop och undersöktes sedan med ett smälttest för att kvantifiera antalet mikroplaster. Även referensprover med kranvatten som genomgått samma provtagningsprocedur som lakvattnet analyserades för att se om mikroplaster från andra källor än lakvattnet kan ha påverkat lakvattenproverna. I lakvattenproverna från avfallsanläggningarna med deponi återfanns mikroplastkoncentrationer mellan 0 och 2,7 mikroplastpartiklar per liter. I referensproverna återfanns mellan 0,2 och 1,7 mikroplastpartiklar per liter. På grund av liknande koncentrationer i lakvattenproverna och referensproverna gick det inte att säga om mikroplasterna fanns i lakvattnet eller om de enbart kom från på kontamination vid provtagning och analys. Resultaten indikerade därför att behandlat lakvatten från avfallsanläggningar med deponier innehåller låg eller ingen halt mikroplast ≥ 100 mikrometer. Avfallsanläggningen utan deponi som undersöktes i studien var en sorteringsanläggning. Från denna anläggning återfanns mellan 2,3 och 4,2 mikroplastpartiklar per liter i lakvattenproverna medan motsvarande siffra för referensprovet var 0,2 mikroplastpartiklar per liter. Skillnaden mellan mikroplastkoncentrationerna i lakvattenproverna och referensprovet indikerar att mikroplasterna eventuellt berodde på avfallsverksamheten. Därmed är det möjligt att mikroplaster från andra avfallsverksamheter än deponering eventuellt kan släppas ut med behandlat lakvatten. För sorteringsanläggningen togs dock enbart ett stickprov. Därför krävs ytterligare studier på sorteringsanläggningar behövs för att bekräfta resultaten. Mängdberäkningar baserade på de uppmätta mikroplastkoncentrationerna, antaget att mikroplasterna fanns i lakvattnet, indikerar att eventuella utsläpp av mikroplaster ≥ 100 mikrometer via behandlat lakvatten från svenska avfallsanläggningar med deponi maximalt är i storleksordningen tiotals kilogram per år. Detta innebär att behandlat lakvatten från avfallsanläggningar är en obetydlig källa till mikroplaster i förhållande till andra mikroplastkällor i Sverige. / Researchers and authorities worldwide recognize the substantial accumulation of microplastics in the oceans as well as the uptake of these microplastics by various living organisms. Microplastics are often defined as plastic particles smaller than five millimeters and can originate from several anthropogenic activities. The majority of all plastics ever produced are accumulated in landfills or the natural environment. Since studies have found plastic additives in leachate from landfills, landfill leachate is thought to be a possible source of microplastic emissions. In this study, the occurrence of microplastics ≥ 100 micrometers was examined in treated leachate from eight waste facilities in Sweden: seven with landfills and one without. The leachate was filtered through filters with a 100 micrometer pore size. Particles on the surface of the mesh were examined under a stereo microscope and then further investigated by a melting test in order to quantify the number of microplastic particles. To see if the leachate samples might have been contaminated with microplastics from other sources, reference samples were analyzed by letting tap water go through the same sampling procedure as the leachate samples. In the leachate samples from the waste facilities with landfills, microplastic concentrations between 0 and 2.7 microplastic particles per liter were found. In the control samples the corresponding concentrations were between 0.2 and 1.7 microplastic particles per liter. Due to similar concentrations in the leachate and control samples, it was impossible to determine if the microplastics originated from the leachate or came from contamination via sampling and analysis. The results of the study therefore indicate that the microplastic concentrations in treated leachate from landfills are low or even nonexistent. The waste facility without a landfill in the study was a sorting facility. At this facility, microplastic concentrations between 2.3 and 4.2 microplastic particles per liter were found in the leachate samples. In the control sample the corresponding concentration was 0.2 microplastic particles per liter. The difference between the concentrations in the leachate samples and control sample indicate that some of the microplastics might have originated from the leachate. Therefore it is possible that other microplastics from waste activities than landfilling can end up in the leachate. However, this result is only based on one sample. Studies including more samples from more sorting facilities are needed to confirm these results. Mass calculations based on the microplastic concentrations, assuming that detected concentrations originated from the leachate, indicate that if microplastics ≥ 100 micrometers are emitted through the leachate from Swedish landfills the maximum emission is only a few tens of kilograms per year. This makes treated leachate from waste facilities insignificant in comparison to other known microplastic sources in Sweden.

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