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1
Pouliot, Julie-Marie. "Biological treatment of landfill leachate." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0005/MQ42192.pdf.
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Zhao, Renzun. "Management strategy of landfill leachate and landfill gas condensate." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77186.
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Studies were conducted to evaluate the impact of landfill leachate discharge on the operation of waste water treatment plants (WWTPs). Two aspects of interferences were found: one is UV quenching substances, which are bio-refractory and able to penetrate the biological treatment processes, consequently interfere the UV disinfection in WWTPs. The other one is organic nitrogen, which can pass the nitrification-denitrification process and contribute to the effluent total nitrogen (TN). Also, treatability study was conducted for landfill gas (LFG) condensate. In a laboratory study, leachate samples were fractionated into humic acids (HA), fulvic acids (FA) and Hydrophilic (Hpi) fractions, the specific UV254 absorbance (SUVA254) of the three fractions follows: HA > FA > Hpi. However, the overall UV254 absorbance of the Hpi fraction was important because there was more hydrophilic organic matter than humic or fulvic acids. It was found that the size distribution of the three fractions follows: HA > FA > Hpi. This indicates that membrane separation following biological treatment is a promising technology for the removal of humic substances from landfill leachates. Leachate samples treated in this manner could usually meet the UV transmittance requirement of the POTWs. Also, nitrogen species in landfill leachates under various stabilization states were investigated. Although the effect of landfill stabilization state on the characteristics of organic matter and ammonia is well documented, there are few investigations into the landfill leachate organic nitrogen under different stabilization stages. Ammonia was found to leach out slower than organic matter and can maintain a constant level within the first a couple of years (< 10 years). The concentration and biodegradability of organic nitrogen were found to decrease with landfill age. A size distribution study showed that most of organic nitrogen in landfill leachates is < 1 kDa. The protein concentration was analyzed and showed a strong correlation with the organic nitrogen. Different slopes of regression curves of untreated and treated leachates indicate that protein is more biodegradable than the other organic nitrogen species in landfill leachates. XAD-8 resin was employed to isolate the hydrophilic fraction of leachate samples, hydrophilic organic nitrogen was found to be more biodegradable/bioavailable than the hydrophobic fractions. Furthermore, biological and physical-chemical treatment methods were applied to a landfill biogas (LFG) condensate to explore the feasible treatment alternatives for organic contaminant and arsenic removal efficiency. Sequencing batch reactor (SBR) showed effectiveness for the degradation of organic matter, even in an environment containing high levels of arsenic. This indicated a relatively low toxicity of organic arsenic as compared to inorganic arsenic. However, for arsenic removal, oxidation-coagulation, including biological oxidation, conventional oxidation and advanced oxidation followed by ferric salt coagulation, and carbon adsorption were not effective for what is believed to be tri-methyl arsenic. Among these, advanced oxidation-coagulation showed the best treatment efficiency (15.1% removal). Only reverse osmosis (RO) could reduce the arsenic concentration to an acceptable level to meet discharge limits. These results implied high stability and low toxicity of organic arsenic.<br>Ph. D.
3
Zalesny, Jill Annette. "Phytoremediation of landfill leachate using Populus." [Ames, Iowa : Iowa State University], 2007.
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Cheung, Kwai Chung. "Purification of landfill leachate by microalgae." HKBU Institutional Repository, 1991. https://repository.hkbu.edu.hk/etd_ra/7.
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Burrows, Mark Robert. "Landfill hydrogeology and the hydraulic properties of in situ landfilled material." Thesis, Royal Holloway, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286066.
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Zhang, Chi. "Struvite Precipitation of Ammonia from Landfill Leachate." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34492.
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The application of struvite (magnesium ammonium phosphate,!MgNH&PO& ∙ 6H+O)
precipitation and its recycling use for the purpose of ammonia removal from both
synthetic solutions and landfill leachate were investigated in this study. The results
demonstrated that chemical precipitation by struvite formation is efficient for ammonia
removal from aqueous solutions. In addition, by recycling the thermal residue of struvite,
continuously removing ammonia can technically be achieved.
In the struvite precipitation, ammonia removal significantly depended on the pH and
chemical molar ratios of NH&
,:!Mg+,:!PO& ./. For synthetic solution (TAN=1,000 mg/L),
remarkable TAN removal efficiency of over 98% has been reported when the molar ratio
of NH&
,:!Mg+,:!PO& ./ equals 1.0:1.2:1.2, 1.0:1.3:1.3, 1.0:1.3:1.4 and 1.0:1.5:1.5 at
optimum pH 9. The optimum combinations of reagents applied in landfill leachate
(TAN=1,878 mg/L) were!NH&
,:!Mg+,:!PO& ./ =1.0:1.3:1.3, 1.0:1.4:1.3, 1.0:1.5:1.4 and
1.0:1.5:1.5 at optimum pH 9.5, all of which displayed excellent TAN removal
efficiencies of over 99%. Response surface method (RSM) helped to analyze the data and
optimize the results.
The struvite pyrolysate provided best performance of removing ammonia in both
simulated wastewater and landfill leachate at a dosage of 60 g/L, when struvite was
previously heated at 105 by oven for 2.5 h. In the recycling phase, the struvite
pyrolysate resulting from NaOH-mediated pyrolysis was more effective at continuously
treating ammonia synthetic solution than was direct heating, with an initial mode of
87.4% at the beginning to 75.1% in the fifth round and direct heating of struvite from
80.9% in the first cycle and 60.6% in the final cycle. The struvite pyrolysate formed by
NaOH-mediated pyrolysis performed with greater ability to continuously eliminate
ammonia from landfill leachate (97.2% removal at the beginning and 72.3% in the fifth
round), than did directly heated struvite (98.4% in the first cycle and 81.3% in the final
cycle). Additionally, microwave irradiation could also dissociate struvite, which
subsequently demonstrated moderate TAN removal in recycling phases.
7
Brachman, Richard W. I. "Mechanical performance of landfill leachate collection pipes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0006/NQ42503.pdf.
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Nie, Jing. "Landfill Leachate Treatment by Fenton's Reagent Oxidation." Thesis, University of Louisiana at Lafayette, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1585908.
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<p> Fenton's Reagent Oxidation can significantly enhance the COD removal efficiency of landfill leachate. The results presented in this thesis show that the maximum amount of COD that could be removed by Fenton's Reagent Oxidation was about 80% of the initial value. Such a maximum removal was achieved using reagent dosage of 300 mg/L of H<sub>2</sub>O<sub>2</sub>, 55.84 mg/L of Fe<sup> 2+</sup>, and a pH of 3 at 25°C. </p><p> A mechanistic model was developed based on the kinetic reactions. A coefficient α, representing the proportional constant between organic matter and COD was firstly introduced to this model. This model fit the data well. The modeling coefficients of α, [·OH] and <i>k</i><sub>7</sub> are 0.013mol <i>mg</i><sup>-1</sup>, 1.65×10<sup>-9</sup> <i> M</i> and 1.55×10<sup>-9</sup> <i>M</i><sup>-1 </sup><i>s</i><sup>-1</sup>, respectively. Hydroxyl radical concentration was calculated and the results confirm the pseudo steady state assumption. Response surface design and analysis results predicted that COD remaining can achieve the lowest value of 48 mg/L with the treatment conditions of a reaction time of 3.8 hours, a pH of 2.3, and a mass ratio of H<sub>2 </sub>O<sub>2</sub> to Fe<sup>2+</sup> of 38 at 60°C.</p>
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Ochieng', Otieno Frederick A. "Impact of recirculation on landfill leachate quality." Thesis, University of Newcastle Upon Tyne, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235556.
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Freewood, Robert John. "Landfill leachate attenuation characteristics of colliery spoil." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390711.
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Sousa, João Alexandre Bastos. "" Landfill leachate treatment: a new photobioreactor technology"." Master's thesis, Instituto de Ciências Biomédicas Abel Salazar, 2009. http://hdl.handle.net/10216/25559.
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Simoes, Ana M. "Natural attenuation of landfill leachate by clays." Thesis, University of Southampton, 2005. https://eprints.soton.ac.uk/79337/.
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Clabaugh, Matthew McConnell. "Nitrification of Landfill Leachate by Biofilm Columns." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33547.
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Landfill leachate characteristics vary depending on the operation type of the landfill and the age of the landfill. At landfills operated as bioreactors, where leachate recirculation is practiced, leachate ammonia nitrogen concentrations may accumulate to extremely higher levels than during single pass leaching, thereby requiring treatment before final discharge to a receiving system (Onay, 1998). Usually several physical/chemical wastewater treatment technologies are used to treat the leachate. In most cases the COD and BOD are treated, and then nitrification is performed in a separate sophisticated ex situ system. The additional costs of these systems can be very high. The use of a readily available media for in situ nitrification should be considered a prime objective to avoid extra costs.
The possibility of removing ammonia nitrogen from bioreactor landfill leachate using trickling filter biofilm technology was studied in four laboratory scale reactors filled with four different types of packing media. The different packing media were examined to see which media is the most efficient at supporting ammonia removal biofilms. The highest efficiency was achieved by a packing media consisting of pine wood chips. The effects of varied concentration loading, varied hydraulic loading, and nitrification inhibitors were studied. Varied ammonia concentration did not have a huge impact on the ammonia removal rates (77-87%) in the reactor with pine wood media. The ammonia removal rates showed a strong dependence on hydraulic loading rate with the lowest loading rate producing the highest removal rates. Landfill leachate from the Middle Peninsula Landfill in Glens, Virginia was determined not to contain nitrifying inhibitors. Using a wood media filter chip and a low hydraulic loading rate was determined to be the best method to remove ammonia nitrogen from landfill bioreator leachate.<br>Master of Science
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Sousa, João Alexandre Bastos. "" Landfill leachate treatment: a new photobioreactor technology"." Dissertação, Instituto de Ciências Biomédicas Abel Salazar, 2009. http://hdl.handle.net/10216/25559.
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Shashikumar, Bangalore M. "Effect of leachate on the stability of landfill composite liners." Ohio : Ohio University, 1992. http://www.ohiolink.edu/etd/view.cgi?ohiou1173217012.
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Yu, Dong. "Landfill Leachate Treatment Case Study, SRV Atervinning, Sweden." Thesis, KTH, Industriell ekologi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32772.
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SRV återvinning AB is a joint-stock waste company located in the south of Stockholm. Since the first operation, three landfills have been practiced successively. The landfill generates about 200,000 to 250,000 cubic meters of leachate per year. An on-site leachate treatment plant consists of sequencing batch reactor (SBR) and constructed wetland was build for Landfill III. The research was to find out: - the capacity and efficiency of the existing on-site leachate treatment plant; - to analyse the costs and environmental benefits of different alternatives; and - using the above results, to assess and suggest supplementary methods to treat total landfill leachate concerning the site-specific conditions. This thesis contains a literature review of leachate production and composition as well as leachate treatment technologies. The technologies are described, evaluated or compared. The contents of this thesis divided into 11 chapters. Various calculations and assumptions that have been developed for effective controlling and treating leachate from landfills. Chapter 1 is devoted to basic facts of the leachate problems at SRV återvinning AB. Chapter 2 presented the methodologies that have been set up for solutions and suggestions. Chapter 3 provides a general background of the generation and compositions of waste leachate. A general overview of leachate treatment methods and systems is presented in Chapter 4. Costs of different leachate treatment methods is also exhibited. Chapter 5 provides a detailed current situation review of SRV återvinning AB on landfilling site, leachate quality and quantity and the existing treatment plant. Chapter 6 showed the previous application experience from other treatment plant. The calculation and comparison procedure for the capacity and efficiency of the plant at the landfill is presented in Chapter 7. Different alternatives to solve the leachate problem concerning the site-specification are proposed in Chapter 8. Their applicability, effectiveness are analyzed. Chapter 9 provides detailed discussion of alternatives and calculation procedure. After the conclusion of the thesis, recommendations for the further work are presented. This thesis will provide SRV återvinning AB different alternatives to solve leachate problems. Finally, considering the site-specification, economic perspective and environmental benefits, applying reverse osmosis after SBR as final step; the combination of aerated lagoon, sand filter and soil infiltration are proposed. Furthermore, the control of leachate production is also taken into account. Eventually, recommendations for the further work were presented.<br>www.ima.kth.se
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Scott, Jennifer (Jennifer E. )., of Western Sydney Hawkesbury University, and Faculty of Science and Technology. "Designing a constructed wetland to treat landfill leachate." THESIS_FST_XXX_Scott_J.xml, 1995. http://handle.uws.edu.au:8081/1959.7/600.
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The aim of this project was to identify a suitable solution to the problem of landfill leachate at the North Katoomba landfill site. Options were affected by a range of constraints including economics, location and the intrusion of ground water into the landfill. The initial goal was to contain and treat the leachate on site, with the eventual target to discharge into the nearest receiving waters. A constructed wetland option was devised and researched, involving identification of the major pollutants contained within the leachate, developing a concept design and estimating the likely removal efficiencies expected. Investigations identified the primary pollution parameters as microbial and nutrients. Metals were found to be low in concentration although the wetland has the capacity to deal with these pollutants should they become part of the pollution plume. A bench scale constructed wetland system was developed to give an indication of the removal efficiencies. The results suggest that a constructed wetland system would be appropriate for treating landfill leachate at the North Katoomba site. It is recommended that a constructed wetland be established in the field to determine the long term treatment prospects and the potential management problems in a practical application.<br>Master of Science (Hons)
18
Linderoth, Maria. "Biochemical characterisation of landfill leachate toxicity in fish." Doctoral thesis, Stockholm : Department of Applied Environmental Science (ITM), Stockholm university, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-951.
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Shoaeioskouei, Saba. "Perfluorinated compounds in landfill leachate from discarded carpets." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42522.
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Perfluorinated compounds (PFCs) are a class of anthropogenic chemicals incorporated over six decades into a wide range of industrial and consumer-use products including surface treatments for carpets and textiles, paper and packaging, non-stick cookware, firefighting foams and insecticides. The extremely strong carbon-fluorine bond, "the strongest in organic chemistry", makes them thermally and chemically stable, and resistant to degradation. Several studies on toxicology of PFCs demonstrate negative health effects of these compounds. Some PFCs were added to the Stockholm convention on Persistent Organic Pollutants (POPs) in 2009, due to their persistence, toxicity, and widespread occurrence in the environment. Stain-resistant carpets comprise a major part of global historical PFC production and use. Landfills are a major source of PFC emissions to the environment as final destinations for discarded consumer articles, including carpets. This thesis explores how various PFCs leach from carpets to landfill leachate, and how factors like temperature, pH and contacting efficiency affect the transfer of PFCs into aqueous media.
Experiments were conducted in which a number of carpets manufactured in ~2000 to 2005 were contacted with landfill leachate and distilled water. Transfer of different PFCs into the aqueous phase increased with contacting time, with differences between 1 and 24 h much greater than between 24 and 168 h. A temperature increase from 5 to 35oC resulted in a significant increase in PFC leaching. Increasing the pH from 5 to 8 resulted in an increase followed by a decrease in leaching of most PFCs. The overall leaching rates of PFCAs into distilled water were somewhat greater than into landfill leachate. The majority of PFC exchange between carpets and leachate was more dependent on some factor (e.g. adsorption or desorption) rather than external mass transfer.
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Williamson, Kimberley. "Soil - vegetation based remediation studies of landfill leachate." Thesis, Bangor University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393608.
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Chu, Kuang-Chi Kevin Yelias. "Landfill Leachate Sorption Potential of Kate Valley Soils." Thesis, University of Canterbury. Civil Engineering, 2014. http://hdl.handle.net/10092/10041.
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Kate Valley is a municipal waste landfill situated in Waipara, Northern Canterbury. It is a joint venture between the 6 local regional councils and Transwaste Canterbury Ltd to help dispose of waste quantities generated in the wider Canterbury region. Landfill waste disposal also generates waste streams. Major waste streams can include methane gas production and liquid leachate. One practice which can turn liquid leachate waste streams into a nutrient source for plants is land irrigation. It is important to have a thorough understanding of the interactions involved with leachate, soil structure, soil microbiology, flora. This thesis investigates the sorption mechanisms between Kate Valley soil and leachates, through batch and column experiments.
Sorption mechanisms between leachate and soil were investigated through batch and column tests. Ex-situ soil samples were extracted from Kate Valley, along with raw leachate samples for batch tests at a soil to liquid ratio of 30 g vs. 70 ml respectively. Tested dilution leachate strengths ranged from raw to 50x raw leachate dilution; meanwhile soil samples were categorized into 3 groups based on soil depth: 0-20 cm, 20-40 cm, and 40-60 cm.
Column tests were conducted on 3 extracted in-situ soil column monoliths. Column test irrigation conditions included: control case, 2x and 10x raw leachate dilution, and 200 mg/L KBr (bromide column), where the same soil column was used for bromine testing after control testing had ceased.
Batch results suggest deeper soils are less effective at sorption of ammonia, where partitioning coefficient ranged from 9.5x*10-7 to 6.4*10-7 L/mg for 0-20 cm soil to 40-60 cm soil respectively. Column results generally showed lower partitioning capacity than batch results, at 4*10-8 and 5*10-8 L/mg for 10x and 2x dilution leachate irrigation respectively.
Discrepancies in experimental data have been attributed to: different dilution leachates tested between batch and column tests, making it difficult for direct comparison; extreme soil to liquid ratios employed in experiments; direct data comparison between the “full-contact” experimental data (between leachate and soil), obtained from batch tests with column results, where not all soil may have been fully exposed for shrinkage of boundary layers of soil particles; and oxygen exposure of samples during testing and sampling, possibly encouraging nitrification.
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Batarseh, Eyad. "Chemical and Biological Treatment of Mature Landfill Leachate." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2698.
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This dissertation is about treatment of the nonbiodegradable organic content of landfill leachate by chemical oxidation combined with biological treatment. It is divided into three parts. In the first part, ferrate was compared to Fenton's reagent for the purpose of removing non-biodegradable organic compounds from mature leachate. Oxidation conditions (time, pH, and dose) were optimized to yield maximum organic removal using two leachate samples from 20 and 12-year old solid waste cells. Results from this research demonstrated that ferrate and Fenton's reagent had similar optimum pH ranges (3-5), but different organic removal capacities, ranging from 54 to 79 % of initial leachate organic contents. An advantage of ferrate was that it was relatively effective over a wide pH range (Fenton's reagent lost its reactivity outside optimum pH range). Advantages associated with Fenton's reagent include a higher organic removal capacity, production of more oxidized organic compounds (measured as chemical oxygen demand/dissolved organic carbon), and production of more biodegradable byproducts (measured as 5-day biochemical oxygen demand/chemical oxygen demand). Finally, both treatments were found to oxidize larger molecules (>1000 dalton) and produce smaller molecules, as indicated by an increase in smaller molecule contribution to organic carbon. In part two, effects of Fenton's reagent treatment on biodegradability of three landfill leachates collected from a Florida landfill were evaluated using biochemical oxygen demand (BOD), biochemical methane potential (BMP), and tertamethylammonium hydroxide (TMAH) thermochemolysis gas chromatography/mass spectrometry (GC/MS). The hypothesis was that Fenton's reagent will remove refractory compounds that inhibit biodegradation and will produce smaller, more biodegradable organic molecules which will result in an increase in BOD and BMP values. Both BOD and BMP results demonstrated that Fenton's reagent treatment did not convert mature leachate to biodegradable leachate, as indicated by a low BOD5 expressed as C /dissolved organic carbon (DOC) ratio of almost 0.15 in treated samples and a low net methane production / theoretical methane potential (less than 0.15). Ultimate BOD only slightly increased. However the first-order BOD reaction rate increased by more than five fold, suggesting that Fenton's reagent removed refractory and inhibitory compounds. BMP results demonstrated that the ratio of CO2/CH4 produced during anaerobic biodegradation did not increase in treated leachate (compared to untreated), indicating that small biodegradable organic acids produced by oxidation were removed by coagulation promoted by Fenton's reagent. Finally, the TMAH thermochemolysis results showed that several of the refractory and inhibitory compounds were detected fewer times in treated samples and that carboxylic acids did not appear in treated samples. In the third part of this dissertation the application of flushing/Fenton's reagent oxidation to produce sustainable solid waste cells was evaluated. A treatment similar to pump and treat process utilizing Fenton's reagent on-site treated leachate combined with in-situ aeration was proposed. Treated leachate would be recycled to the landfill cell flushes releasable nonbiodegradable carbon from the cell and oxidizes it externally. This technique was demonstrated to have treatment cost and time benefits over other alternatives for producing completely stable solid waste cells such as anaerobic flushing and biological and/or mechanical pretreatment of solid waste (used in the EU).<br>Ph.D.<br>Department of Civil and Environmental Engineering<br>Engineering and Computer Science<br>Environmental Engineering
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Langler, Glenn J. "Aquatic toxicity and environmental impact of landfill leachate." Thesis, University of Brighton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406763.
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Kylefors, Katarina. "Landfill leachate management : short and long term perspectives." Licentiate thesis, Luleå tekniska universitet, 1997. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18352.
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Kakalanga, Sumbu. "Nickel pollution abatement from landfill leachate using biomaterials." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/748.
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Thesis submitted in fulfilment of the requirements for the degree of
Master of Technology: Chemistry
in the Faculty of Applied Sciences
at the Cape Peninsula University of Technology, 2012<br>Batch experiments were conducted to assess the removal of Ni(II) from aqueous solutions and landfill leachates using low cost adsorbents eggplant peel (EGP), sweet potato peel (SWP) and banana peel (BNP). Preliminary studies were carried out to optimize biosorbent mass, pH, Ni(II) concentration, temperature and contact time for Ni(II) removal. The optimized conditions were then applied to landfill leachates using the selected low cost adsorbents.
Ni(II) removal efficiency for each biosorbent was investigated for each parameter. Results indicated that biosorbents masses, pH, initial concentration as well as solution temperature were important factors influencing Ni(II) removal from aqueous solutions. Percentage Ni(II) removal was 66±0.30, 38±3.97 and 33±1.20 using EGP, SWP and BNP, respectively. Ni(II) removal efficiency increased significantly (P ≤ 0.05) with increasing biosorbent mass, pH and Ni(II) initial concentration while it decreased significantly (P ≤ 0.05) with increasing temperature. Although Ni(II) removal efficiency varied significantly with time and the biosorbents no significant (P 0.05) difference was observed between the time interval whether the experiment was conducted in batch or semi batch mode.
Results of FTIR studies indicated that several binding and chelating functional groups such as carboxyl, carbonyl and hydroxyl groups on the biomaterials surfaces could be responsible for Ni(II) biosorption.
The optimum biosorbent mass for EGP and SWP was 0.4 g and for BNP was 0.05 g. The values for initial concentration, pH, temperature and contact time were 100 mg/L, 5, 22oC and 2 hours, respectively. Ni(II) removal efficiencies using EGP, SWP and BNP were 66, 38 and 33%, respectively.
Taking into account the result and optimum condition obtained on Ni(II) removal efficiency from aqueous solution using EGP, SWP and BNP, the Ni(II) removal efficiency using these biosorbents from landfill leachate was investigated. It was found to be significantly (P ≤ 0.05) lower than what was found from aqueous solution.
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Rahman, Mohammad Hafizur. "Spatial and temporal analysis of landfill leachate characteristics at Trail Road Landfill site." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28484.
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This study is conducted at the Trail Road Landfill, located in Nepean, Ontario, Canada. The objective is to investigate the leachate characteristics of changing spatial-temporal patterns in a landfill groundwater environment by comprehensive analyses of annual spatial data.
Exploratory statistical data analysis identified the association of B (boron) with K, NH3 and TKN. Raster layers (maps) are created based on the concentrations of required variables in each time interval (year). In this study, it is notable that the raster data layers are used instead of discrete well data.
Several change detection methods are applied to determine the spatial and temporal changes of B and its associated variables and to identify the well locations where the changes occurred. These included post-classification visualization, principal component analysis, standard deviation and unsupervised classification (clustering) methods. The suitability of these methods is also discussed. The results determined that during the 1993-95 time period the concentrations of B and its associates was initially increasing, and then decreased substantially.
In summary, the study analysed characteristics of pollutants in landfill site groundwater environmental monitoring by using raster data in different change detection methods, and discussed the suitability of the applied methods. The same methodology and analysis techniques can be applied to other variables in similar environmental monitoring studies.
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Hon, Siu-ming. "Ultimate form of recycling : integrated landfill management: leachate recirculation, landfill gas utilization and landfill mining : are they applicable to Hong Kong? /." Hong Kong : University of Hong Kong, 1995. http://sunzi.lib.hku.hk/hkuto/record.jsp?B14709272.
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Gulati, Loveenia. "Characteristics and Treatment of Landfill Leachate and Optimization of Leachate Oxidation with Fenton's Reagent." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/76771.
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The purpose of this study was to characterize the leachate from a landfill in Pennsylvania that had been pretreated by activated sludge and propose the most efficient treatment for this effluent. These samples had been pretreated in a sequencing batch reactor that also was operated to remove nitrogen by nitrification/denitrification. The SBR samples were found to have low BOD, high COD, high TOC and a very low BOD/COD ratio. These SBR decant samples have poor UV transmittance and hence quench UV light. Five treatment methods were evaluated, coagulation, ultrafiltration, combined coagulation/ultrafiltration, combined ultrafiltration/oxidation and combined filtration/fentons. These processes were tested for their ability to remove BOD and TOC and also to evaluate the improvement in UV transmittance. It was found that coagulation; Ultrafiltration and Ultrafiltration combined with coagulation do not work in improving the transmittance properties though there is a significant BOD and TOC removal with these processes. Ultrafiltration combined with oxidation was found to work the best in terms of TOC removal. In this study, four oxidants, KMnO?, H?O?, NaOCl and Fenton's reagent were used. It was observed that Fenton's reagent was capable of removing 90% TOC at a dose of 1g/L each of iron salt and hydrogen peroxide at a pH of 4.5. Since Fentons reagent was found to be the most effective method, hence, efforts were made to optimize the oxidation process with Fenton's. The two parameters which were studied were the initial pH and the chemical dosage. The initial pH was varied from a value of 2.5 to 6.5. The range of iron salt and peroxide dose used was from 0.05 to 0.1 g/L. Additional studies were conducted using samples filtered through a 0.45 um filter and oxidized with Fenton's reagent. The Fenton's process for oxidation of filtrates from the 0.45?m filter was also optimized with respect to pH and chemical dosage to determine the most economical operating conditions. The maximum transmittance of 57% was obtained for an iron dose of 0.075 g/L and a peroxide dose of 0.075 g/L at a pH of 4.5. This is in comparison to the transmittance of unoxidized 1K ultrafiltrate which was found to be 21.5%. There was a significant difference in the performance of 1K and 0.45um filtrates in terms of TOC removal and percentage transmittance. The oxidation process for improving the UV transmittance of leachate can therefore be economically optimized depending upon the desired efficiency by varying the operational parameters.<br>Master of Science
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Bricker, Garrett Demyan. "Analytical Methods of Testing Solid Waste and Leachate to Determine Landfill Stability and Landfill Biodegradation Enhancement." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/35162.
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This was a study undertaken to investigate municipal solid waste (MSW) landfill stability parameters and landfill leachate properties to determine how solid waste and leachate characteristics can be used to describe stability. The primary objective was to determine if leachate properties could be used to determine stability of the overlying refuse. All landfills studied were engineered landfill bioreactors giving insight to how leachate recirculation affects stability.
This study investigated the correlation between cellulose, lignin, volatile solids, and biochemical methane production (BMP). These parameters can been used to characterize landfill stability. The BMP tests indicate that a saturated waste can produce methane. Cellulose is an indicator of landfill stability. Wastes high in cellulose content were found to have high BMP. Paper samples studied indicated gas production from high-cellulose paper was higher compared to low-cellulose samples. Lignin has been found to correlate fairly well with BMP. Increasing cellulose to lignin ratios correlate well with increasing BMP levels, further supporting the use of the BMP test to indicate solid waste stability.
In the BMP test for leachate, a mixture of the standard growth medium (less 80% distilled water) and 80% v/v leachate incubated for 15 days produced the most consistent BMP results. Leachate cellulose and BMP correlated well. The chemical oxygen demand (COD) and biochemical oxygen demand (BOD) also had some correlation to BMP tests. Leachate COD was found to decrease over time in landfill bioreactors. The use of leachate rather than MSW to determine stability would be more efficient.<br>Master of Science
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La, Forge François. "Attenuation of landfill leachate by a natural marshland system." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/6764.
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Since the early 1980's, leachate originating form the Alice and Fraser municipal landfill has been discharging in a natural marshland system located some 300 meters downgradient form the waste disposal site. However, monitoring of the water quality within the marshland indicates that the contaminant level has not yet surpassed background concentration downstream from the main impact area. A mathematical model was developed in an attempt to predict the mobility of several contaminant species within the marshland environment. Parameters needed for the predictive model were gathered based on the physical configuration of the landfill and marshland associated with laboratory derived data on the attenuation capacity of the marshland soil matrix. The behavior, transport and ultimate fate of contaminants in organic soil is greatly affected by their participation in sorption reactions. The adsorption potential of lead, zinc, calcium, sodium and pentachlorophenol (PCP) by marshland soil was evaluated in laboratory through both, batch and column experiments. A multidimensional finite-difference model based on the Advection-Dispersion Equation was used to predict the migration of the above mentioned contaminants. (Abstract shortened by UMI.)
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Fleming, Ian R. "Biogeochemical processes and clogging of landfill leachate collection systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0007/NQ42518.pdf.
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Hurd, Sarah M. "Low-pressure reverse osmosis membrane treatment of landfill leachate." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0025/MQ52299.pdf.
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Mashal, Ahmad Tawfig. "Treatment of landfill leachate by Fenton and plasma technologies." Thesis, Queen's University Belfast, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.579793.
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Advanced oxidation processes, namely photo-Fenton, Fenton-like, Fenton and UV/H202 and plasma have been investigated for the removal of organic matters from landfill leachate. Fenton's oxidation was the most effective and the most effective ratio 1/10 (Fe2+/H202) COD removal reached 50-80% and the biodegradability increased by 40 to 60 %. The oxidation batch treatment was performed on different synthetic leachate concentration and two types of doses:(single and triple Fenton's reagents. The first single Fenton's reagent removal efficiency of COD was less than those of a triple Fenton's reagents for all tested leachates under similar operating conditions. The COD removal of domestic landfill leachate and a glucose based-synthetic one as a function of the operating variables (H202, Fe2+, Ti02 , UVand Plasma) led to results that ranged between 30% and 90% while the removal efficiencies decreased in the order: photo-Fenton > Fenton-like > Fenton > UVIH202, > UV. Fenton process however generated an important quantity of iron sludge which will require further disposal. The advanced plasma process which relies on cold liquid plasma as source of light for radical productions was used as a new technique to treat landfill leachate solutions. The efficiency of single plasma process and its combination with conventional Fenton catalytic process as an integrated process on COD removal were investigated. The experimental procedure was carried out in a bench-scale continuous stirred tank catalytic reactor where the plasma unit probe was immersed in the liquid phase generating periodic pulses for various periods of time. The process involved the use of both Fe2+ catalyst and hydrogen peroxide while the plasma process required an additional NaCl diluted solution to promote the electrolysis by increasing the conductivity of the operating solutions.
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Spraggs, Rachael Elizabeth. "Novel approaches for removal of ammonium from landfill leachate." Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493601.
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Arab, F. K. "A study of desorption of ammonia from landfill leachate." Thesis, University of Strathclyde, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304813.
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Score, Jodie. "Sustainable landfill leachate treatment using a willow vegetation filter." Thesis, University of Northampton, 2007. http://nectar.northampton.ac.uk/2671/.
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The utilisation of a willow vegetation filter for the treatment of landfill leachate is an environmentally and economically appealing solution for landfill operators. Investigations into the design and efficacy of the system, the effects of landfill leachate irrigation on soil ecology, soil chemistry and willow growth were undertaken. Two low cost, high density polyethylene-lined experimental willow plots (25x50 m2) were installed at Cranford landfill, Northamptonshire, UK, and irrigated with landfill leachate between June 2001 and October 2005. During the growing season, leachate volume was often reduced to zero. On other occasions, maximum removal efficiencies of between 33 % and 75 % for total Kjeldahl nitrogen, chemical oxygen demand and sodium, potassium and chloride ions were determined in landfill leachate effluent samples. The addition of landfill leachate produced no negative effects on both soil and foliar macronutrients, which were found to be in the range for sufficient or optimum growth and where additional fertilisers would not bring about a further increase in yields. The effects of landfill leachate application on soil microbial communities were explored and were found to be significantly higher for dehydrogenase activity and ammonium oxidising bacteria in the plot receiving a higher rate of leachate application. An economic analysis was carried out to demonstrate the financial viability of a willow vegetation filter as a treatment for landfill leachate. Willow vegetation filters could provide a desirable alternative to conventional treatment systems, such as sequencing batch reactors, as they incur lower capital expenses and potentially similar operational costs. This study also identified additional revenue benefits in the region of £94 per hectare for wood chip heat/energy production. The results from the willow vegetation filter under investigation in this study demonstrated that this type of system can be effective, in terms of volume reduction and removal efficiency in landfill leachate, with no detrimental effect upon the trees or surrounding environment
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Macmillan, Janet Mary. "Modelling of landfill leachate attenuation in acidic groundwater environments." Thesis, Royal Holloway, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392284.
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Kastner, Robert Eugene Lee. "Structural performance of plastic pipe used for landfill leachate collection." Ohio : Ohio University, 1992. http://www.ohiolink.edu/etd/view.cgi?ohiou1172687975.
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Duarte, Inês Alexandra Barros Serra. "The main leachate emissions of uncontrolled landfills." Master's thesis, Faculdade de Ciências e Tecnologia, 2014. http://hdl.handle.net/10362/12312.
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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, Perfil de Engenharia Sanitária<br>One of the biggest current problems is the proper management of solid waste and
other waste streams. All types of waste have a potential pollutant affecting soil
resources and water resources, mainly in landfills that may not have adequate
protection measures and do not know the waste placed in them.
Through the study on laboratory scale it is possible to check which potential emissions
to the level of leachates of uncontrolled landfills. The leachates can be compared. It is
possible to say which ones have more heavy metals and organic fraction emissions.
This study analyzed samples of leachate from two landfill waste in North-East Italy,
near Verona, two old uncontrolled landfills. The leachate samples come from the
simulation of biological reactors, operated in aerobic and anaerobic condition. The
leachates were characterized in terms of pH, heavy metals such as Cd, Cr, Cu, Fe, Mn,
Ni Pb, Zn, As and Hg and organic fraction (TOC, TKN and NO3).
The heavy metal and organic fraction concentrations were found low in order of
micrograms, and in the organic fraction in order of milligrams, per litre of leachates. In
general, the concentrations in the anaerobic bioreactors were higher than in the aerobic
bioreactors.
The study showed that pH is a very important factor regarding the mobility of the
metals in the leachate. The quality of the leachates in study have little potential for
water pollution since they exhibit basic pH values (around 8), even if the residues are
saturated, that is, the ability of field reached.
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Chafer, Morag A. "An investigation of the interaction between landfill leachate and soils." Thesis, University of Strathclyde, 1990. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21265.
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A detailed review of literature reveals that although soil scientists have reported that soil is an excellent stabiliser of land applied waste, there is little evidence to assess the extremely complex reactions that occur when landfill leachate interacts with soil. In order to examine this, studies of mineralogical content, exchangeable cation status and chemical composition of soils were undertaken. Soil-leachate interactions were studied by column and batch techniques. When dealing with materials as variable and complex as soils, it is difficult to accurately identify the solid phase prior to contact. Owing to the large number and variety of concentrations of leachate constituents, it is considerably more difficult to quantitatively establish the results of interaction and assign alteration values to responsible mechanisms. However, this investigation did reveal the following: - 1. interaction does occur, but this interaction is not unlimited; 2. the degree of interaction is different for different soil types; 3. the relative influence of the mechanisms of interaction; 4. the influence of soil types, soil to leachate ratios and contact -times; and 5. soils previously thought to attenuate leachate have been found not to do so.
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Schwarze, Susann. "Volatile organic compounds in landfill gas as indicators of waste degradation processes." Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270125.
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Lo, Huang-Mu. "The impact of increasing the incinerator ash content on landfill site biostabilisation." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368050.
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Hon, Siu-ming, and 韓兆明. "Ultimate form of recycling: integrated landfill management: leachate recirculation, landfill gas utilizationand landfill mining : are they applicable to Hong Kong?" Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31253143.
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North, Jessica C., and n/a. "Stable isotope tracers of landfill leachate impacts on aquatic systems." University of Otago. Department of Chemistry, 2006. http://adt.otago.ac.nz./public/adt-NZDU20070504.144317.
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The present study aimed to determine whether stable isotope techniques can be universally applied to detect landfill leachate contamination in aquatic systems. Results of analysis of ��C in dissolved inorganic carbon ([delta]��C-DIC), deuterium and �⁸O in water ([delta]D-H₂O and [delta]�⁸O-H₂O), and �⁵N of dissolved inorganic nitrogen components ([delta]�⁵N-NH₄⁺ and [delta]�⁵N-NO₃⁻) were presented for leachate, surface, and ground water samples collected from seven landfills located throughout New Zealand between 2003 and 2006. The unique conditions within a landfill lead to measurable fractionations in the isotopic ratios of the products of degradation. Results of isotope and ancillary parameter analyses enabled the discernment of different types of leachate, resulting from different microbial processes within the landfill environment. The isotopic characterisation of leachate enabled improved interpretation of geochemical data from potentially impacted surface and ground waters, and provides useful insight to landfill development for landfill operators. A general isotopic fingerprint delineated by [delta]��C-DIC and [delta]D-H₂O values showed leachate to be isotopically distinct from uncontaminated surface and ground water for samples analysed in the present study. However, not all water samples identified as leachate-impacted via site-specific assessments exhibited isotopic values that overlapped with the general leachate fingerprint. This highlights the need to investigate each site individually, within the context of a possibly global leachate isotope signature. Site-specific investigations revealed the effectiveness of applying [delta]�⁸O-H₂O and [delta]�⁵N-NH₄⁺ or [delta]�⁵N-NO₃⁻, in addition to [delta]��C-DIC and [delta]D-H₂O analyses, to the detection of leachate impact on aquatic systems. Furthermore, ancillary parameters such as alkalinity and ammonium concentration enabled the construction of simple isotope mixing models for an estimate of the quantity of leachate contribution. Results of isotopic investigations of stream biota suggested potential for the development of bio-indicators to monitor leachate influence on aquatic ecosystems in landfill-associated streams. The present study demonstrated the probative power of stable isotope techniques applied to investigations of leachate impact on landfill-associated aquatic systems.
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Benbow, Timothy J., and n/a. "Developing compound-specific stable isotope tools for monitoring landfill leachate." University of Otago. Department of Chemistry, 2008. http://adt.otago.ac.nz./public/adt-NZDU20080314.111826.
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This thesis has developed a suite of compound specific stable isotope tools to monitor landfill leachate and identify the infiltration of leachate to ground water and surface water. These tools have the power to indicate the fractional contribution multiple discrete sources of pollution are making to a single location. This journey began by developing two solid phase extraction (SPE) methods to extract non-polar and polar organic compounds from leachate with minimal fractionation of hydrogen or carbon isotopes. Non-polar compounds were successfully extracted using ENV+ SPE cartridges and polar compounds were successfully extracted using Strata-X SPE cartridges. The isotopic fractionation of non-polar compounds during ENV+ extraction varied significantly (up to 245⁰/₀₀ and 1.8⁰/₀₀ for D and ��C respectively, when eluted with acetonitrile and ethyl acetate, as recommended by manufacturers) but the fractionation of compounds eluted with dichloromethane was negligible (less than instrumental precision). Polar compounds were eluted from Strata-X cartridges with negligible isotopic fractionation using methanol. The direct comparison of SPE and liquid-liquid extraction found SPE to extract slightly more compound from leachate then liquid-liquid extraction (especially for polar compounds) and the isotopic compositions of compounds did not change with extraction methods.
These new analytical methods subsequently were used to determine the isotopic compositions of organic compounds dissolved in leachates from three New Zealand landfills. The molecular and isotopic signature of leachate varied significantly between landfills, indicating the isotopic fingerprint of organic compounds in leachate is unsuitable as a universal tracer of leachate. However, compounds such as terpien-4-ol, methylethylbenzene and juvabione maintained their isotopic composition over short geographical distance-indicating their potential as site-specific tracers of leachate. Organic compounds analysed on a transect across the landfill boundary indicated polar compounds were more mobile than semi-volatile compounds and possessed a more conservative isotopic composition. However, hexadecanoic acid extracted from leachate and ground water was highly depleted in ��C (-72 ⁰/₀₀ to -40⁰/₀₀), indicative of methanogenic and sulfate reducing bacteria. These bacteria only live in highly reducing environments such as leachate; therefore their presence in the pristine environment can potentially indicate the release of leachate from the landfill.
The final experiments traced the uptake and utilisation of leachate by periphyton. The isotopic composition of bulk periphyton, fatty acids and phytol indicated that microbial assimilation and utilisation of nutrients is a complex process. Fatty acid biomarkers for green algae and diatoms showed signs of leachate derived nutrients, however the availability of nutrients (carbon, nitrogen, water and light) caused significant changes in metabolic processes and isotopic compositions. Under slow growing conditions, the [delta]��C composition of periphyton became enriched in ��C as solar irradiation levels decreased (including shading by detritus and periphyton), while the [delta]D composition of fatty acid was controlled by the internal recycling of hydrogen. This study indicated the power of compound specific isotope analysis as a tool to detect the release of landfill leachate from a landfill, especially at locations with multiple potential sources of contaminants, and provides a sound platform for future research.
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Khan, Taj Ali. "Numerical modelling of leachate production and movement within landfill sites." Thesis, University of Strathclyde, 1996. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21962.
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This research project considers the development of numerical simulation processes of the production and management of leachate from landfill sites. The existing landfill leachate management models are reviewed and analysed on the basis of their applicability and effectiveness, identifying a number of important deficiencies in these models. These models simplify the actual flow process in the waste matrix and assume the same density throughout the simulation period. Moisture flow through waste material is investigated through experiments, and as a result different mathematical models were developed. These models represent the effect of density on the hydraulic properties of waste material such as: moisture capacities, drainage rates and saturated hydraulic conductivity. The effect of density is identified as the fundamental parameter governing the flow phenomena in waste material. A large database of information obtained provides a better interpretation of statistical analyses, in fitting statistical distributions to parameters and to cover the variability of waste material. A basic applied numerical model named NUMMOL (NUMerical MOdelling of Leachate) is developed based on the water balance approach, which simulates the leachate production, movement and distribution within landfill sites. NUMMOL incorporates the most appropriate mathematical models representing the various landfill hydrological processes. The moisture flow through waste layers is modelled using the models derived through experimental investigation. The model's limitations and assumptions are discussed with suggestions for future work that is necessary to enhance further its applicability. Sensitivity analysis and evaluation of the simulation capabilities of the NUMMOL model are included. It was found that correct identification of the hydraulic properties of the landfill material is very important. To investigate model usefulness and efficiency as an environmental planning tool, the individual components of the model are evaluated. It was found that the model iterative scheme is very effective in simulating leachate movement in a cell and leachate distribution within cells. The model was applied to the landfill site in order to compare the effect of layers on leachate distribution.
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Orme, Dini Ramya. "Acceleration of landfill stabilisation by waste pulverisation and leachate recirculation." Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333976.
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Davies, Lorna Annette. "The low cost treatment of landfill leachate using constructed wetlands." Thesis, University of Leeds, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275678.
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Milad, Ziad Abdelsalam. "An experimental investigation of landfill leachate impact on surrounding soil." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/68312/.
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Landfill leachate is generated as a consequence of water percolation through the solid wastes, oxidation of the wastes, and corrosion of the wastes. Underdesigned landfill sites allow the leachate to easily pass through the soil strata. This may have an impact on the engineering properties of soils, such as the shear strength and the volume change (compressibility and swelling), and the chemical properties (adsorption and retention of heavy metals). In this thesis, a detailed experimental investigation was undertaken to investigate the effects of landfill leachate contamination on the geotechnical and geo-environmental properties of natural soils of Kuwait. Two soils (a silty sand and a clayey sand) were used in the study. The soils were obtained from the Al-Jahra landfill site based in Kuwait. The leachate was collected from the Al-Qurain landfill site in Kuwait. The results from the direct shear and consolidation tests on compacted soil specimens that interacted with leachate and water indicated that, the influence of contamination was severe on the engineering properties of the clayey sand than that of the silty sand. The geoenvironmental properties of the soils were studied to assess the transport and fate of heavy metals in the soils. Leaching column tests were carried out to establish the breakthrough curves which showed retention of heavy metals (As, Cr, Cu and Ni) by both soils. The results from batch isotherm adsorption tests were used to study the ability of the soils to adsorb heavy metals. The test results showed that, heavy metal adsorption was superior in the clayey sand than that occurred in the silty sand. The leaching column test results was used to validate the HYDRUS 1D software package. The results from the model and the laboratory tests results were found to be in good agreements. The bearing capacity and settlement behavior of the soils were modelled. The settlement behavior of the soils was found to be more pronounced due to the presence of landfill leachate. The conclusions drawn from the experimental and numerical investigations favour a further understanding of some of the key issues associated with the transport and fate of leachate in the surrounding environment of a landfill site.
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Liu, Xingjian. "Membrane Electrochemical Treatment of Landfill Leachate: Processes, Performance and Challenges." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/105173.
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Landfilling is the most common approach to dispose of municipal solid wastes but inevitably leads to leachate formation. Persistent UV quenching substances (UVQS) in landfill leachate can affect the effectiveness of UV disinfection in municipal wastewater treatment systems when leachate co-treatment is applied. Membrane electrochemical reactor (MER) treatment was investigated to reduce the UV quenching capability and simultaneously recover resources in the leachate as an effective onsite pre-treatment. Ion-selective membranes were used in this MER to create two different conditions: a low-pH anolyte for organic oxidation and a high-pH catholyte for ammonia recovery. The MER achieved significantly higher removals of both dissolved organic carbon and UV254nm absorbance than membrane-less electrochemical treatment. The MER was able to remove a large percentage of total nitrogen from the leachate while recovering about half of the influent ammonia in the catholyte with less specific energy consumption. The second study coupled MER with Fenton oxidation through providing synergistic benefits with the low solution pH, reduced organics, and ammonia removal. This two-stage coupled system reduced the more leachate COD than the standalone Fenton process treating raw leachate. Also, the usage of chemicals as Fenton reagents has been greatly reduced: FeSO4 and H2O2 by 39%, H2SO4 by 100%, and NaOH by 55%. Consequently, the sludge production was reduced by 51% in weight and 12% in volume. Despite electricity consumption by the MER, the coupled system cost $4.76 per m3 leachate less than the standalone Fenton treatment. More notably, direct Fenton oxidation removed only 21% of ammonia; in comparison, the MER-Fenton system removed ammonia by 98% with the possibility for recovery at a rate of 30.6 -55.2 kg N m-3 reactor d-1. Those results demonstrated that coupling MER with the Fenton process could mitigate some inherent drawbacks of Fenton oxidation such as ineffective ammonia removal, high acid and chemical reagents dose requirements, and a large amount of sludge generation. The third study investigated the formation of total halogenated organics (DBP) and the associated toxicity as the side effect of leachate treatment in the MER. Compared to the 4538±100 µg L-1 from the control membrane-less electrochemical oxidation reactor, the amount of DBP generated in the MER only accounted for 19.1±4.5 % after the same treatment period. The total toxicity value (26.6 ×10-3 ) was low for MER effluent, only 15.1% of that in the control group. Both high pH and high ammonia concentration introduced more DBP mass and toxicity production after MER treatment. DBP concentrations were shown to increase with applied current density and possible temperature raise. With 67.5% of DBP mass concentration and 74.4% of the additive toxicity removal, the granular activated carbon (GAC) electrode system was shown more effective than GAC adsorption alone in remediating DBP harmful effects. This dissertation introduced MER as a promising technology for the treatment of leachate through performance demonstration, process integration and by-product remediation.<br>Doctor of Philosophy<br>Municipal solid waste is often disposed of in landfills because of the most economics and convenience. However, one of the most challenging problems is the leachate formation and treatment. In the US, leachate is currently often diluted in domestic wastewater treatment systems; meanwhile, the persistent contaminants in landfill leachate can lower the effectiveness of UV disinfection and result in high cost and permit violation. In this study, the membrane electrochemical reactor (MER) using electricity as the driving force was applied to solve the issue and simultaneously recover valuable resources in the leachate. Membranes as a barrier for selective ions were used in this MER to create two different conditions with different purposes: a low-pH anolyte for organic oxidation and a high-pH catholyte for ammonia recovery. The MER achieved significantly higher contaminants removals than membrane-less electrochemical treatment. The second study coupled MER with one of the established advanced oxidation processes, also known as Fenton oxidation through providing mutual benefits with the low solution pH, reduced organics, and ammonia removal/recovery. This two-stage coupled system reduced the leachate contaminants effectively towards the direct discharge standard. In addition, the usage of chemical reagents, as well as the amount of process residual, has significantly been reduced. The third study investigated the formation of by-products as the side effect of leachate treatment in the MER. Compared to the membrane-less reactor, the undesirable by-products generated in the MER only accounted for one fifth after the same treatment period. A granular activated carbon electrode system was shown effective in remediating the harmful effects. This dissertation introduced MER as a promising technology for the treatment of leachate as one of the toughest wastewaters.