To see the other types of publications on this topic, follow the link: Landfill bioreactors.
Dissertations / Theses on the topic 'Landfill bioreactors'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Landfill bioreactors.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
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.
Full textAbstract:
Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, Perfil de Engenharia SanitáriaOne 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.
2
Peeling, Louise. "Landfill drainage as a fixed-bed bioreactor." Thesis, Queen Mary, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298468.
Full text
3
Murphy, Timothy J. "A comparative evaluation of liquid infiltration methods for bioreactor landfills." Connect to resource, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1086213619.
Full textAbstract:
Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xvii, 342 p.; also includes graphics. Includes bibliographical references (p. 164-171). Available online via OhioLINK's ETD Center
4
Myers, Michael John. "Laboratory Scale Solid State Landfill Bioreactor Design." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu1393077896.
Full text
5
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.
Full textAbstract:
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.Master of Science
6
DeAbreu, Ricardo. "Facultative Bioreactor Landfill: An Environmental and Geotechnical Study." ScholarWorks@UNO, 2003. http://scholarworks.uno.edu/td/39.
Full textAbstract:
A relatively new concept of Municipal Solid Waste treatment is known as bioreactor landfill technology. Bioreactor landfills are sanitary landfills that use microbiological processes purposefully to transform and stabilize the biodegradable organic waste constituents in a shorter period of time. One of the most popular types of bioreactor landfills is the landfill with leachate recirculation. However, it is observed that ammonia rapidly accumulates in landfills that recirculate leachate and may be the component that limits the potential to discharge excess leachate to the environment. In the facultative landfill, leachate is nitrified biologically using an on-site treatment plant and converted by denitrifying bacteria to nitrogen gas, a harmless end-product. In this research, three pilot-plant scale lysimeters are used in a comparative evaluation of the effect of recirculating treated and untreated leachate on waste stabilization rates. The three lysimeters are filled with waste prepared with identical composition. One is being operated as a facultative bioreactor landfill with external leachate pre-treatment prior to recirculation, the second is being operated as an anaerobic bioreactor landfill with straight raw leachate recirculation, and the third one is the control unit and operated as a conventional landfill. Apart from environmental restrictions, geotechnical constraints are also imposed on new sanitary landfills. The scarcity of new potential disposal areas imposes higher and higher landfills, in order to utilize the maximum capacity ofthose areas. In this context, the knowledge of the compressibility of waste landfills represents a powerful tool to search for alternatives for optimization of disposal areas and new solid waste disposal technologies. This dissertation deals with and discusses the environmental and geotechnical aspects of municipal solid waste landfills. In the Environmental Engineering area, it compares the quality of the leachate and gas generated in the three lysimeters and discusses the transfer of the technology studied through lysimeters to procedures for full-scale operation. In the geotechnical area, this dissertation discusses the compressibility properties of the waste and provides a state-of-the-art review of MSW compressibility studies. It also evaluates the compressibility of MSW landfills for immediate and long-term settlements and proposes a new model for compressibility of waste landfills.
7
Price, G. Alexander. "LONG-TERM NITROGEN MANAGEMENT IN BIOREACTOR LANDFILLS." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20011214-153926.
Full textAbstract:
One scenario for the long-term nitrogen management in landfills is ex-situ nitrification followed by denitrification in the landfill. The objective of this research was to measure the denitrification potential of actively decomposing and well decomposed refuse. A series of 10-L reactors that was actively producing methane was fed 400 mg NO3-N /L every 48 hr for19 to 59 days. Up to 29 nitrate additions were either completely or largely depleted within 48 hr of addition and the denitrification reactions did not adversely affect the refuse pH. Nitrate did inhibit methane production but the reactors recovered their methane-producing activity with the termination of the nitrate addition. In well decomposed refuse, the nitrate consumption rate was reduced but was easily stimulated by the addition of either acetate or an overlayer of fresh refuse. Addition of a high acetate to nitrate ratio did not lead to the production of NH4+ by dissimilatory nitrate reduction. Although the population of denitrifying bacteria decreased by about five orders of magnitude during refuse decomposition in a reactor that did not receive nitrate, rapid denitrification commenced immediately with the addition of 400 mg NO3-N/L. These data suggest that the use of a landfill as a bioreactor for the conversion of nitrate to a harmless byproduct, nitrogen gas, is technically viable.
8
Wolfe, Kevin Brian. "First principles and artificial neural networks modeling of waste temperatures in a forced-aeration landfill bioreactor : a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /." Click access online version, 2006. http://proquest.umi.com/pqdweb?index=96&did=1115122181&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1256313131&clientId=28564.
Full text
9
Niemietz, Roberta. "Effects of Temperature on Anaerobic Lignin Degradation in Bioreactor Landfills." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/36051.
Full textAbstract:
Bioreactor landfills have become a feasible alternative to the typical â dry tombâ landfill. By recirculating leachate and/or adding additional liquid wastes, bioreactor landfills operate to rapidly degrade and transform organic wastes. The reactions within a bioreactor landfill create elevated temperatures. The intent of this study was to determine the effect of elevated temperature on the degradation of lignocellulose compounds. In order to observe the effects of temperature on lignin, small bioreactors were created in the laboratory. Several experiments were performed by the authors. Solubility of lignin based on temperature and time of thermal exposure were conducted. In addition, degradation studies were conducted based on biological treatment of lignin as well as a combination of biological and thermal treatment. Samples were collected at specified intervals to determine the amount of water soluble lignin (WSL), volatile fatty acids (VFAs), lignin monomers, and/or methane present. Lignin solubility increased as temperature rose in the thermal solubility experiments. The rate of solubility increased 15 times for office paper and 1.5 times for cardboard in the biological experiments when compared to the thermal treatment. The thermal and biological study indicates that as lignin is solubilized, it breaks down into lignin monomers, which can be converted easily by anaerobic bacteria into VFAs and subsequently, methane. These experiments indicate that temperature is crucial to the degradation of lignin compounds in a bioreactor landfill.Master of Science
10
Berge, Nicole. "IN-SITU AMMONIA REMOVAL OF LEACHATE FROM BIOREACTOR LANDFILLS." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3281.
Full textAbstract:
A new and promising trend in solid waste management is to operate the landfill as a bioreactor. Bioreactor landfills are controlled systems in which moisture addition and/or air injection are used as enhancements to create a solid waste environment capable of actively degrading the biodegradable organic fraction of the waste. Although there are many advantages associated with bioreactor landfills, some challenges remain. One such challenge is the ammonia-nitrogen concentration found in the leachate. The concentrations of ammonia-nitrogen tend to increase beyond concentrations found in leachate from conventional landfills because recirculating leachate increases the rate of ammonification and results in accumulation of higher levels of ammonia-nitrogen concentrations, even after the organic fraction of the waste is stabilized. Because ammonia-nitrogen persists even after the organic fraction of the waste is stabilized, and because of its toxic nature, it is likely that ammonia-nitrogen will determine when the landfill is biologically stable and when post-closure monitoring may end. Thus an understanding of the fate of nitrogen in bioreactor landfills is critical to a successful and economic operation. Ammonia-nitrogen is typically removed from leachate outside of the landfill. However, additional costs are associated with ex-situ treatment of ammonia, as separate treatment units on site must be maintained or the leachate must be pumped to a publicly owned wastewater treatment facility. Therefore, the development of an in-situ nitrogen removal technique would be an attractive alternative. Several recent in-situ treatment approaches have been explored, but lacked the information necessary for field-scale implementation. The objectives of this study were to develop information necessary to implement in-situ ammonia removal at the field-scale. Research was conducted to evaluate the kinetics of in-situ ammonia removal and to subsequently develop guidance for field-scale implementation. An aerobic reactor and microcosms containing digested municipal solid waste were operated and parameters were measured to determine nitrification kinetics under conditions likely found in bioreactor landfills. The environmental conditions evaluated include: ammonia concentration (500 and 1000mg N/L), temperature (25o, 35o and 45oC), and oxygen concentration in the gas-phase (5, 17 and 100%). Results suggest that in-situ nitrification is feasible and that the potential for simultaneous nitrification and denitrification in field-scale bioreactor landfills is significant due to the presence of both aerobic and anoxic areas. All rate data were fitted to the Monod equation, resulting in an equation that describes the impact of pH, oxygen concentration, ammonia concentration, and temperature on ammonia removal. In order to provide design information for a field-scale study, a simple mass balance model was constructed in FORTRAN to forecast the fate of ammonia injected into a nitrifying portion of a landfill. Based on model results, an economic analysis of the in-situ treatment method was conducted and compared to current ex-situ leachate treatment costs. In-situ nitrification is a cost effective method for removing ammonia-nitrogen when employed in older waste environments. Compared to reported on-site treatment costs, the costs associated with the in-situ ammonia removal process fall within and are on the lower end of the range found in the literature. When compared to treating the leachate off-site, the costs of the in-situ ammonia removal process are always significantly lower. Validation of the laboratory results with a field-scale study is needed.Ph.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering
11
Kelly, Ryan J. "Solid Waste Biodegradation Enhancements and the Evaluation of Analytical Methods Used to Predict Waste Stability." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/32484.
Full textAbstract:
Conventional landfills are built to dispose of the increasing amount of municipal solid waste (MSW) generated each year. A relatively new type of landfill, called a bioreactor landfill, is designed to optimize the biodegradation of the contained waste to stabilized products. Landfills with stabilized waste pose little threat to the environment from ozone depleting gases and groundwater contamination. Limited research has been done to determine the importance of biodegradation enhancement techniques and the analytical methods that are used to characterize waste stability. The purpose of this research was to determine the effectiveness of several biodegradation enhancements and to evaluate the analytical methods which predict landfill stability.
In the first part of this study leachate recirculation, and moisture and temperature management were found to significantly affect the biodegradation of MSW. Leachate recirculation, increased moisture, and higher temperatures increased the first order degradation rates of cellulose and volatile solids. Of the three enhancements, temperature was shown to have the biggest impact on the biodegradation of waste, but sufficient moisture is critical for degradation. Plastic material was also shown to significantly impact the measurements for volatile solids and lignin, which is important if these measurements are used to establish waste stability.
In the second part of the study the analytical methods used to characterize waste were evaluated to determine if relationships existed between the methods and which methods were the best predictors of waste stability. Volatile solids and cellulose were found to be the best parameters to monitor waste in landfills. These parameters correlate well with each other, age of the waste, and other parameters. Volatile solids and cellulose are also relatively easy to determine, quick, and show little variation.Master of Science
12
Muir, Robert. "Monitoring and evaluation of the Mid-Auchencarroch Shallow Landfill Bioreactor Test Cells." Thesis, Glasgow Caledonian University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415441.
Full text
13
Abdallah, Mohamed E. S. M. "A Novel Computational Approach for the Management of Bioreactor Landfills." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20314.
Full textAbstract:
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.
14
El, Khatib Dounia. "Municipal Solid Waste in Bioreactor Landfills: A Large Scale Study." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1289943004.
Full text
15
Clabaugh, Matthew McConnell. "Nitrification of Landfill Leachate by Biofilm Columns." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33547.
Full textAbstract:
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.Master of Science
16
Boda, Borbala. "Evaluation of Stability Parameters for Landfills." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/34399.
Full textAbstract:
There are more than three thousand landfills in the United States, in which approximately 55% (1998, U. S. EPA 1999) of the MSW generated in the US is buried. The majority of the landfills are conventional, but in the last two decades new types of landfills, called leachate recycle and bioreactor landfills, have been designed and tested as an enhanced environment for biochemical degradation of municipal solid waste. All the landfills are regulated under Subtitle D of the Resource Conservation and Recovery Act (RCRA). The shortage of time and money has limited the amount of research done on waste stability analysis. The purpose of this study was to evaluate the importance of lignocelluloses in biodegradation and the secondary settlement based on dry density and typical landfill evaluating parameters.
Both parts of the study samples were collected and analyzed from eleven landfills. In the first part of the study, bioreactor landfills were found more effective, faster in the degradation of VS and cellulose as compared to conventional landfills. The time required for stabilization is reduced to about 1/3 that of conventional landfills. The lignocelluloses degradation that occurs in these landfills is happening in two phases. In the initial, rapid degradation phase, the primary degradation substrate is cellulose. In the second phase, after cellulose degraded to 15-20% of the waste, degradation of the remaining cellulose along with lignin and the hemicelluloses takes place. The start of lignin and hemicellulose degradation results in an increase in the biochemical methane potential (BMP).
In the second part of the study, the addition of moisture to the landfills presented a contentious issue. Moisture is encouraged for MSW refuse degradation, but for settlement it reduces compressibility. In leachate recycle landfills, the dry density is higher than in conventional landfills; therefore there is more available room for further MSW load. The increase can reach up to 40 percent in total volume.Master of Science
17
Kim, Jongmin. "Effect of plastics on the lignin results for MSW and the fate of lignin in laboratory solid waste reactors." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/35579.
Full textAbstract:
Cellulose to lignin ratio is one of the widely used indicators of degree of landfill stabilization. This ratio shows the amount of carbohydrate or cellulose consumed by anaerobes compared to relatively inert lignin. However, the method of lignin measurement contains an intrinsic error. Plastics are contained in the landfill samples and these are characterized as lignaceous materials due to their acid-insolubility. Lignin is typically measured as the organic residue that is acid insoluble but is combustible upon ignition. Additionally lignin may degrade under anaerobic, high temperature conditions associated with wet conditions in sediments and bioreactor landfills.
In this study, it has been found that the typical measure of lignin, a gravimetric measure, also includes plastics, leading to erroneous measures of both lignin and the cellulose/lignin (C/L) ratio. Typically, 100% of the plastic will be measured as lignin. Since plastic amounts to approximately 10% of landfill contents, lignin measurements will be 10% greater than actual amounts. Laboratory reactors were set up with known amounts of paper and plastic. The degradation of the cellulose and lignin in paper was measured and compared to plastics, which was collected by hand and weighed. Ratios of cellulose to plastics and lignin to plastics were obtained. It was found, based on the cellulose to plastic ratio and lignin to plastic ration that lignin degrades under anaerobic conditions although at a much slower rate than cellulose. These findings indicate that the cellulose to lignin ratio cannot be used as the sole indicator of stabilization in the landfills. The inclusion of the biochemical methane potential test data along with C/L is thought to provide a better indication of landfill stabilization.
Master of Science
18
Irani, Ayesha. "Biochemical Lignin Related Processes in Landfills." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/36492.
Full textAbstract:
The objective of this study was to determine how the key features of bioreactor landfills; increased temperature, moisture and microbial activity, affect the biological stability of the landfill material. In the first part of the study the solubilization and degradation of lignin in paper exposed to these bioreactor landfill conditions are explored. The solubility of the lignin in paper was observed at different temperatures and over 27 weeks at 55°C and the anaerobic bioconversion of office paper, cardboard and Kraft lignin was observed in bench-scale reactors over 8 weeks. As the temperature rose, lignin solubility increased exponentially. With extended thermal treatment, the dissolution of lignin continues at a constant rate. This rate increases 15 times for paper and 1.5 times for cardboard in the presence of rumen inoculum compared to un-inoculated systems. At around 6 weeks the inter-monomeric linkages between the solubilized lignin molecules began breaking down, releasing monomers. In cardboard and Kraft lignin, a significant amount of the monomers mineralize to CO2 and CH4 during this time period. The results indicate that small, but significant rates of lignin solubilization and anaerobic lignin degradation are likely to occur in bioreactor landfills due to both higher temperature and microbial activity.
In the second part of the study, field data from the Outer Loop Recycling and Disposal Facility in Louisville, Kentucky was evaluated to determine the effectiveness of an anaerobic-aerobic landfill bioreactor (AALB) vs. the control landfill that is managed as a traditional landfill. Moisture, temperature, elevation and the amount of time the MSW has spent in the landfills (age) were measured and compared to determine the factors that affect the biological stability of the landfill. The results showed that the MSW in the AALB is more biologically stable than the MSW in the control landfill, indicating that they are more degraded. Additionally, elevation or location of the MSW was the key factor in determining the extent of MSW stability within the AALB and temperature is the key factor in determining the biological stability of the MSW in the control landfill. Higher temperatures correlated with a more biologically stable waste. The cellulose to lignin ratio (C/L ratio) and biochemical methane potential (BMP) were the main biological stability parameters used.
Master of Science
19
Shearer, Brad David. "Enhanced Biodegradation in Landfills." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33215.
Full textAbstract:
The objective of this paper is to evaluate the effectiveness of leachate recirculation and bioreactor landfills at enhancing biodegradation, and to optimize the operation of a bioreactor. Waste Management has been examining leachate recirculation landfills for several years. Samples of Municipal Solid Waste (MSW) from existing leachate recirculation (LR) landfills were collected and analyzed for several physical and biochemical properties. These parameters of interest were moisture content, pH, density, temperature, volatile solids, cellulose/lignin ratios, and biological methane potential (BMP). Leachate recirculation increased the dry density 55% faster and decreased the BMP 125% more rapidly. Moisture content was the biggest factor influencing overall degradation. Therefore, leachate reciculation effectively increases biodegradation of MSW in landfills.
Waste Management built a pilot-scale bioreactor in Franklin, WI, which was sampled for one year. It contained a bioreactor side and a control side. The volatile solids, cellulose, and BMP degradation rates for the bioreactor were increased by 56%, 87%, and 271% versus the control, respectively. Moisture content was the biggest factor influencing overall degradation.
The column study is designed to optimize three parameters under the control of an operator: moisture content, initial aeration period, and biosolids addition. The optimum moisture content is above 45%, but it is not safe to operate heavy equipment on refuse with greater than 45% moisture. Initial aeration did not speed up the overall degradation, but it did shorten the acidogenic phase. Finally, biosolids did not have a significant effect on degradation rates. The columns maintained an average temperature of 70oF.Master of Science
20
Wingfield-Hayes, Crispin. "The controlled landfill bioreactor : a sustainable waste management option for the 21st century?" Thesis, University of Strathclyde, 1997. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=23485.
Full text
21
Do, Anh Tien. "Anaerobic Membrane Bioreactor (AnMBR) for Treatment of Landfill Leachate and Removal of Micropollutants." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3075.
Full textAbstract:
To date, most studies on the fate and removal of endocrine disrupting compounds (EDCs) and pharmaceutical and personal care products (PPCPs) in wastewater focus on their fate in municipal wastewater treatment plants, and mostly under aerobic condition. There are limited studies related to anaerobic condition and (to our knowledge) no study on the removal of EDCs in landfill leachate by AnMBR. Moreover, for most studies under anaerobic condition, the removal of EDCs was only reported in the liquid phase; solid phase extraction was not reported, thereby preventing mass balance in the studies.
This research was conducted to investigate the potential of AnMBR for reduction of organic strength and removal of EDCs in landfill leachate. A novel lab-scale upflow anaerobic sludge blanket (UASB) reactor equipped with dual-flat sheet ultrafiltration and microfiltration membrane modules was designed and constructed to test the potential to remove EDCs and traditional landfill leachate constituents (COD, turbidity). The target EDC was 17β-estradiol (E2), a prevalent female hormone used for contraceptives and hormone replacement therapy. Due to the nature of packaging and widespread use in households, the entry of E2 into landfills is highly likely, and has been reported. The quantification of E2 from liquid phase in this project is performed by the use of solid-phase microextraction (SPME) with GC/MS.
Batch assays were conducted to determine the anaerobic biodegradability of E2 as well as to measure the respective distribution coefficients of E2 to PAC, colloids and anaerobic sludge biomass. In the adsorption batch assays, it was found that the PAC has stronger adsorption potential than anaerobic sludge. The adsorption potential of E2, E1 and EE2 on sludge follows the order E2>EE2>E1 which correlates to the Kow values (4.01, 3.67, 3.1, respectively). However, all three compounds showed the same adsorption potential to the Norit 20B PAC. The biodegradability of E2 was investigated in both liquid and solid phase and under several conditions such as methanogenesis, methanogenesis with aid from PAC, and methanogenesis with additional alternative electron acceptors added (sulfate and nitrate). E2 was found to transform to E1 under all tested conditions. The compounds are present in both liquid and solid phase. E2 and E1 were not detected (< 4ng/L and <10ng/L, respectively) in the liquid phase after 25 days in most cases except the case of adding additional sulfate.
The AnMBR was designed, fabricated and operated for 2 years. During the stable condition period of the AnMBR, the high removal efficiencies of COD and E2 achieved were around 92% and 98%, respectively. However, E2 was still detected in the effluent at average concentrations of 30-40 µg/L range. To expand hormone retention and removal by the AnMBR, as well as to control membrane fouling, powder activated carbon (PAC) was added to the reactor. After the PAC was added, the concentration of E2 was reduced to less than the detection limit (4ng/L) in both MF and UF effluents. The log removal of E2 in the AnMBR system increased immediately from 1.7 without PAC to 5.2 after PAC was added. This study demonstrated that the AnMBR has high potential for removal of E2, and with aid from PAC, the AnMBR can remove E2 from landfill leachate to levels below detection limit.
22
Manchala, Karthik Reddy. "Effect of liquid waste addition on the overall performance of anaerobic bioreactor landfill." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/31618.
Full textAbstract:
The effect of high organic liquid wastes on the overall performance of anaerobic bioreactor landfills is not known. In this study three different liquid wastes were added to mix of office paper, newspaper, cardboard and plastic in 3 different concentrations under anaerobic conditions to determine their effect on degradation of organics. The addition of buffer chemicals was found to improve degradation compared to data from an earlier study done without the addition of initial buffering. Paint waste with a COD 237,500 mg/L added at a concentration of 10% did not show any negative effect on the overall performance. The distillation waste with a COD of 812,500 mg/L added at 5% and higher concentration resulted in accumulation of volatile fatty acids and strong inhibition. The surfactant waste added at concentrations up to 1500 mg/L showed some inhibition but the overall performance was good. The surfactant waste also appeared to improve lignin degradation.Master of Science
23
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.
Full textAbstract:
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).Ph.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering
24
Aromolaran, Adewale. "Enhancement of Biogas Production from Organic Wastes through Leachate Blending and Co-digestion." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42509.
Full textAbstract:
Several operational and environmental conditions can result in poor biogas yield during the operation of anaerobic digesters and anaerobic bioreactor landfills. Over time, anaerobic co-digestion and leachate blending have been identified as strategies that can help address some of these challenges to improve biogas production. While co-digestion entails the co-treatment of multiple substrates, leachate blending involves combination of mature and young landfill leachate. Despite the benefits attributed to these strategies, their impact on recirculating bioreactor landfill scenarios and anaerobic digesters requires further investigation.
In the first phase of this thesis, an attempt to assess biogas production improvement from organic fraction of municipal solid waste in simulated bioreactor landfills through recirculation of blended landfill leachate was conducted. Real old and new leachate blends (67%New leachate:33%Old leachate, 33%New leachate:67%Old leachate) as well as 100%New and 100%Old leachate were recirculated through six laboratory-scale bioreactors using open-loop and closed-loops modes. Compared with the control bioreactor where 100% new leachate was recirculated and operated as a closed-loop, cumulative biogas production was improved by as much as 77 to 193% when a leachate blend of 33%New:67%Old was recirculated. Furthermore, comparison of the results from open-loop and closed-loop operated bioreactors indicated that there was approximately 28 to 65% more biogas in open-loop bioreactors. The Gompertz model applied to the methane data produced a better fit (R2 > 0.99) than first order and logistic function models. Leachate blending reduced the lag phase by almost half and thus helps in alleviating the ensiling during the start-up phase.
In the second phase, a biochemical methane potential (BMP) assay was conducted to investigate the synergistic effect of percentage sewage scum addition; 10%, 20% and 40% (volatile solids basis) on biogas production during mesophilic co-digestion with various organic substrates viz; organic fraction of municipal solid waste, old leachate, new leachate and a leachate blend prepared from 67%old leachate and 33%new leachate under sub-optimal condition. Results show that the net cumulative bio-methane yield was improved with increased sewage scum percentage during co-digestion because of positive synergism. Meanwhile, the addition of 40% sewage scum to the individual co-substrates improved net cumulative bio-methane yield by 28% - 67% when compared to their respective mono-substrate digestion bio-methane yield. Furthermore, reactors containing leachate blends consistently produced more biogas over other sets because of blending. Kinetic modelling applied to the bio-methane production data shows modified Gompertz equation achieved a better fit with up to an R2 value of 0.999. Finally, co-digestion substantially reduced the lag time encountered during mono-digestion.
In the last phase, the biomethane potential involved in the ACo-D of sewage scum, organic fraction of municipal solid waste was investigated in this phase using either thickened waste activated sludge or leachate blend (67%old leachate and 33%new leachate) as a tertiary component. Compared to the mono-digestion of TWAS, results shows that biomethane yield was enhanced in by as much as 32 - 127% in trinary mixtures with SS and OFMSW mainly due to the effect of positive synergism. Furthermore, LB addition improved biomethane production in trinary mixtures of SS:LB: OFMSW by 38% than in corresponding trinary mixtures of TWAS. Whereas an optimal combination of 40%SS:10%TWAS:50%OFMSW and 20%SS:70%LB:10%OFMSW produced the highest biogas yield of 407mL.gVS-1 and 487mL.gVS-1 respectively. The application of the first order model showed that lower hydrolysis rates promoted methanogenesis with k = 0.04day-1 in both 20%SS:70%LB:10%OFMSW and 20%SS:50%LB:30%OFMSW. Estimations by the modified Gompertz and logistic function were conclusive methane production rate improved by as much a 60% in a trinary mixture over the production rate during mono-digestion of TWAS alone.
The results of the various experiments of this thesis therefore suggest that leachate blending can be used as a strategy to improve biogas production in both bioreactor landfills and anaerobic digesters. Also, sewage scum as an energy-rich substrate can be better utilized during co-digestion with other low-energy substrates.
25
Gawande, Nitin A. "Modeling microbiological and chemical processes in municipal solid waste bioreactor development and applications of a three-phase numerical model BIOKEMOD-3P /." Orlando, Fla. : University of Central Florida, 2009. http://purl.fcla.edu/fcla/etd/CFE0002659.
Full text
26
Jain, Pradeep. "Moisture addition at bioreactor landfills using vertical wells mathematical modeling and field application /." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0010860.
Full text
27
Mukherjee, Moumita. "Instrumented permeable blankets for estimating subsurface hydraulic conductivity and confirming numerical models used for subsurface liquid injection." Diss., Connect to online resource - MSU authorized users, 2008.
Find full text
28
Jonnalagadda, Sreeram. "Resistivity and time domain reflectometry sensors for assessing in situ moisture content in a bioreactor landfill." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0003501.
Full text
29
Powell, Jon. "Trace gas quality, temperature control and extent of influence from air addition at a bioreactor landfill." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0011349.
Full text
30
Karatt, Vellatt Vijesh. "Effect of sugar waste, surfactant waste and paint waste on the degradation of anaerobic bioreactor landfill components." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/42439.
Full textAbstract:
Anaerobic bioreactor landfills are the landfills with an increased moisture content inorder to achieve a better biodegradation. Many Bioreactor landfills accept outside liquid wastes to achieve a higher moisture content . But the effect of these wastes on the degradation of landfill components is not known.
In this study, the effect of sugar waste, surfactant waste and paint waste on the degradation of landfill components was investigated. Sugar waste, surfactant waste and paint wastes in different concentrations were added to the combination of paper, cardboard, office paper and plastic with a total moisture content of 70%. The samples were incubated, sampled and analytical parameters analyzed. Sugar waste having a COD of 250,000 mg/L in a concentration of even 5% of the total weight was found inhibitive due to a drop in pH and accumulation of volatile fatty acids. Reactors with surfactant concentrations ranging from 50 mg/L to 500 mg/L showed that a higher concentration of 500 mg/L or above may be inhibitive in nature and the inhibition increases with increase in the concentration of surfactant. However, paint waste with a concentration of even 7.5% highly inhibited the degradation in the reactors. This could possibly be because of some toxicity.Master of Science
31
Gawande, Nitin. "MODELING MICROBIOLOGICAL AND CHEMICAL PROCESSES IN MUNICIPAL SOLID WASTE BIOREACTOR: DEVELOPMENT AND APPLICATIONS OF A THREE-PHA." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3803.
Full textAbstract:
The numerical computer models that simulate municipal solid waste (MSW) bioreactor landfills have mainly two components--a biodegradation process module and a multi-phase flow module. The biodegradation model describes the chemical and microbiological processes of solid waste biodegradation. The models available to date include predefined solid waste biodegradation reactions and participating species. In a bioreactor landfill several processes, such as anaerobic and aerobic biodegradation, nitrogen and sulfate cycling, precipitation and dissolution of metals, and adsorption and gasification of various anthropogenic organic compounds, occur simultaneously. These processes may involve reactions of several species and the available biochemical models for solid waste biodegradation do not provide users with the flexibility to selectively simulate these processes. This research work includes the development of a generalized biochemical process model, BIOKEMOD-3P, which can accommodate a large number of species and process reactions. This model is able to simulate bioreactor landfill processes in a completely mixed condition; when coupled with a multi-phase model it will be able to simulate a full-scale bioreactor landfill. This generalized biochemical model can simulate laboratory and pilot-scale operations which are important to determine biochemical parameters important for simulation of full-scale operations. To illustrate application of BIOKEMOD-3P, two sets of laboratory MSW bioreactors were simulated in this research work. The first demonstrated simulation of data from anaerobic biodegradation of MSW in experimental bioreactors. In another application, simultaneous nitrification and denitrification processes in MSW bioreactors were simulated. The results from these simulations generated information about various modeling parameters that would help implement these processes in a full-scale bioreactor landfill operation.Ph.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engineering PhD
32
Cardoso, João Filipe Valverde. "Fate of nitrogen in bioreactor landfills: lab-scale in situ aeration in well decomposed MSW." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/11068.
Full textAbstract:
Dissertação para obtenção do Grau de Mestre em
Engenharia do ambiente, perfil de engenharia sanitáriaIn Europe nowadays waste management is following new trends as recycling and compost processes. However, landfilling continues to have an important role in waste management, in fact, according to SOER 2012, by the year of 2010 37% of MSW was landfilled on EU-27 countries. The future perspective shows that landfilling will continue to be a valid option in the years to come. Landfills have an elevated post-closure time, since at least 30 years of monitoring are legally required. One of the main parameters to achieve landfill stabilization is: the leachate should not contain high concentrations of organics, ammonia, or heavy metals. With this regard operating a landfill as an aerated bioreactor as became an acceptable technique to diminish the aftercare period in the landfill, reducing also the costs of the leachate treatment. In this study six reactors filled with well decomposed MSW are aerated and several ammonium nitrogen and nitrate nitrogen injections (1000 mg N/l) were performed in order to understand the fate of nitrogen under these conditions. Specifically, nitrification and denitrification processes, and a possible volatilization of free ammonia was also monitored. The results shows that ammonium nitrogen was successfully removed in a range of 99,0 to 99,7%. Nitrate, when in the presence of readily available carbon, was removed in a range of 89,9 to 99%, however under well decomposed MSW conditions only 40,8 to 56,6% of nitrate nitrogen removal was achieved. Both autotrophic and heterotrophic denitrification were also assessed in order to understand whether the first occur and which is the obtained efficiency of nitrate removal in both cases.
33
Vaidya, Rajendra D. "Solid Waste Degradation, Compaction and Water Holding Capacity." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/35432.
Full textAbstract:
Bioreactor landfills offer a sustainable way to achieve increased waste degradation along with benefits such as enhanced landfill gas (LFG) recovery, reduction in leachate pollution potential and rapid increase in landfill volumetric capacity. It also offers significant reduction in post closure management activities as leachate treatment, LFG impact on the environment and improves the potential for land reuse. The regulatory 30 year post-closure period is believed to account for attenuation of organics, metals and trace pollutants of adverse environmental consequences. Methodologies to improve the degradation rate and process are refuse shredding, nutrient addition, pH buffering, and temperature control along with moisture enhancement. Municipal Solid Waste (MSW) settlement and field capacity are of significant beneficial interest to achieve maximum utility of landfill volume and compute water requirements for rapid degradation using bioreactor concepts.
Physical and biochemical Municipal Solid Waste (MSW) characteristics were investigated with specific emphasis on the Bio-Chemical methane potential (BMP) test. The impact of waste characteristics on its compressibility and moisture retention capacity was evaluated on a laboratory scale. Traditional in-situ waste compression models from literature were used to compare with the obtained laboratory data.Master of Science
34
Lazarevic, David Andrew. "In-situ Removal of Hydrogen Sulphide from Landfill Gas : Arising from the Interaction between Municipal Solid Waste and Sulphide Mine Environments within Bioreactor Conditions." Thesis, KTH, Industriell ekologi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32770.
Full textAbstract:
This project was compiled in co-operation with the Royal Institute of Technology, Stockholm and Veolia Environmental Services (Australia) at the Woodlawn Bioreactor in NSW, Australia. Hydrogen sulphide is an unwanted component of landfill gas, raising occupational health and safety concerns, whilst leading to acid gas corrosion of power generation equipment and increased emissions of SOx, a primary constituent of acidification. Australian governmental requirements to place a periodic cover over the unused proportion of the tipping surface of landfills and bioreactors create an interesting opportunity for the removal of the hydrogen sulphide component of landfill gas. Using waste materials containing a high concentration of metals as waste cover can enhance the precipitation of sulphur in the form of metal sulphides. The reduction of sulphate via sulphate reducing bacteria is prevalent in sites that have a sizeable inflow of sulphate. The Woodlawn Bioreactor is located in an area where the influence of sulphate has a critical influence of bioreactor performance and production of hydrogen sulphide. Through a series of experimental bioreactors it was established that from the use of metalliferous periodic waste covers, the hydrogen sulphide component of landfill gas was maintained at an extremely low level when compared to the levels of hydrogen sulphide produced in waste under the influence of high sulphate loads with no waste cover.www.ima.kth.se
35
Pathak, Ankit Bidhan. "Two - Stage AnMBR for Removal of UV Quenching Organic Carbon from Landfill Leachates: Feasibility and Microbial Community Analyses." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/84514.
Full textAbstract:
Landfilling is the most widely used method for the disposal of municipal solid wastes (MSW) in the United States due to its simplicity and low cost. According to the 2014 report on Advancing Sustainable Materials Management by the USEPA, only 34% of the total MSW generated in the US was recycled, while 13% was combusted for energy recovery. In 2014, 53% of the MSW generated, (i.e. 136 million tons) in the US was landfilled. The treatment of landfill leachates, generated by percolation of water through the landfill, primarily due to precipitation, has been found to be one of the major challenges associated with landfill operation and management. Currently, leachates from most landfills are discharged into wastewater treatment plants, where they get treated along with domestic sewage.
Issues associated with treatment of landfill leachates due to their high nitrogen and heavy metal content have been widely studied. Recently, it has been observed that the organic carbon in landfill leachates, specifically humic and fulvic acids (together referred to as "humic substances") contain aromatic groups that can absorb large amounts of ultraviolet (UV) light, greatly reducing the UV transmissivity in wastewater plants using UV disinfection as the final treatment step. This interference with UV disinfection is observed even when landfill leachates constitute a very small fraction (of the order of 1%) of the total volumetric flow into wastewater treatment plants. Humic substances are present as dissolved organic matter (DOM) and typically show very low biodegradability. Removing these substances using chemical treatment or membrane processes is an expensive proposition. However, the concentrations of humic substances are found to be reduced in leachates from landfill cells that have aged for several years, suggesting that these substances may be degraded under the conditions of long-term landfilling.
The primary objective of this research was to use a two-stage process employing thermophilic pretreatment followed by a mesophilic anaerobic membrane bioreactor (AnMBR) to mimic the conditions of long-term landfilling. The AnMBR was designed to keep biomass inside the reactor and accelerate degradation of biologically recalcitrant organic carbon such as humic substances. The treatment goal was to reduce UV absorbance in raw landfill leachates, potentially providing landfills with an innovative on-site biological treatment option prior to discharging leachates into wastewater treatment plants. The system was operated over 14 months, during which time over 50% of UV-quenching organic carbon and 45% of UV absorbance was consistently removed. To the best of our knowledge, these removal values are higher than any reported using biological treatment in the literature. Comparative studies were also performed to evaluate the performance of this system in treating young leachates versus aged leachates.
Next-generation DNA sequencing and quantitative PCR (qPCR) were used to characterize the microbial community in raw landfill leachates and the bioreactors treating landfill leachate. Analysis of microbial community structure and function revealed the presence of known degraders of humic substances in raw as well as treated landfill leachates. The total number of organisms in the bioreactors were found to be higher than in raw leachate. Gene markers corresponding to pathogenic bacteria and a variety of antibiotic resistance genes (ARGs) were detected in raw landfill leachates and the also in the reactors treating leachate, which makes it necessary to compare these ARG levels with wastewater treatment in order to determine if leachates can act as sources of ARG addition into wastewater treatment plants. In addition, the high UV absorbance of leachates could hinder the removal of ARBs and ARGs by UV disinfection, allowing their release into surface water bodies and aiding their proliferation in natural and engineered systems.Ph. D.
36
Nair, Arjun. "Effect of Leachate Blending on Anaerobic Digestion of Organic Fraction of Municipal Solid Waste." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24404.
Full textAbstract:
Anaerobic digestion of the Organic Fraction of Municipal Solid Waste (OFMSW) generates a mixture of methane (CH4), carbon dioxide (CO2) and water (H2O). Beyond the field capacity the water generated is collected and recirculated as leachate in Bioreactor Landfills (BLs.) Leachate recirculation has a profound advantage on biodegradation of the Organic Fraction of Municipal Solid Waste (OFMSW) in the landfills. Mature leachate from older sections of landfills (>20 years) and young leachate were blended prior to recirculation in the ratios 3/3 mature, 3/3 young, 1/3 mature-2/3 young and 2/3 old-1/3 young and their effect on biodegradation and biogas production monitored. In addition to analysis of the effect of blending old and new leachates, the study also analyses the effect of an open vs. a closed recirculation loop and the effect of organic loading rates of OFMSW in landfills. Data collected from initial batch tests supplement column bioreactors simulating bioreactor landfills with real world OFMSW from operational landfill facilities in Ontario, Canada. The results are conclusive that the biogas generation can be improved by up to 92% by blending the leachate in an open loop recirculation system as compared to a conventional closed loop system employed in landfills today.
37
Gholamifard, Shabnam. "Modélisation des écoulements diphasiques bioactifs dans les installations de stockage de déchets." Phd thesis, Université Paris-Est, 2009. http://tel.archives-ouvertes.fr/tel-00512102.
Full textAbstract:
Accélérer la dégradation anaérobie des déchets enfouis, optimiser la production de biogaz et diminuer le temps et le coût de surveillance sont les enjeux principaux d'installation de stockage des déchets non dangereux (ISDND)-bioactives, ainsi que, plus classiquement, minimiser leurs impacts sanitaires et environnementaux. L'une des méthodes les plus efficaces pour atteindre ces objectifs est la recirculation de lixiviat et l'augmentation de l'humidité des déchets. Les objectifs du bioréacteur ne seront pas atteints sans une connaissance rationnelle des phénomènes hydrauliques, biologiques et thermiques qui s'y développent et de l'influence de l'un de ces phénomènes sur les autres. Les observations in situ, les expérimentations en laboratoire ainsi que les modèles numériques permettent ensemble une approche rationnelle de ces phénomènes. C'est ce qui constitue le corps de ce travail de thèse, où nous avons étudié le comportement hydro-thermo-biologique des déchets dans la phase anaérobie en laboratoire, sur site à partir de données hydro-thermiques de deux bioréacteurs situés en France et en développant un modèle numérique pour simuler ce comportement couplé des bioréacteurs. Les travaux en laboratoire nous ont permis d'étudier l'effet de la saturation et de la densité (compactage des déchets) sur la dégradation anaérobie des déchets ménagers et l'influence de ces paramètres sur la production de biogaz. Les données hydrauliques et thermiques in-situ des bioréacteurs nous ont permis de connaître les variations des paramètres essentiels comme la température et la saturation dans les déchets, à différentes profondeurs, et estimer d'autres paramètres qui sont difficile à déterminer expérimentalement. Le modèle numérique nous a permis d'étudier le comportement couplé, hydro-thermo-biologique, des bioréacteurs à long terme (pendant une dizaine d'années) aussi bien qu'à court terme pendant la recirculation de lixiviat. L'interdépendance des différents paramètres qui influent la dégradation des déchets est la principale raison nous ayant conduits à développer un modèle de couplage qui nous permette d'étudier chaque paramètre en fonction des autres. Les travaux en laboratoire et les données thermiques de site nous ont conduits à développer un modèle d'écoulement diphasique du liquide et du gaz dans les déchets, considérant les phénomènes biologiques, en fonction des paramètres clés de la dégradation comme la température et la saturation, pour aboutir à la production de biogaz et de chaleur. Les trois parties de ce travail, les expérimentations en laboratoire, le développement d'un modèle numérique et l'analyse des données de site ont été effectuées en parallèle de façon complémentaire. Les expérimentation de laboratoire tout comme l'analyse des données de site, nous ont montré l'importance des paramètres qu'il faut considérer dans le modèle et en retour le modèle numérique nous a aidé à diriger les expérimentations en laboratoire et montré la nécessité de conduire certaines analyses sur les pilotes expérimentaux, comme l'analyse de la biomasse, de la DCO et des AGV. L'analyse des données hydrauliques et thermiques de sites de bioréacteur nous a permis de caler les paramètres hydrauliques, biologiques et thermiques des déchets qui sont difficile à définir sur le site sans le perturber (comme la conductivité hydraulique, la saturation, la conductivité thermique, la capacité calorifique, la concentration en biomasse et en AGV). Le travail réalisé dans la thèse a permis de développer un modèle couplé hydro-thermo-biologique et de tester sa capacité à prévoir le comportement thermique d'un bioréacteur, la production totale et le taux de production de méthane. Nous avons montré qu'il était adopté à l'étude du comportement à long terme d'un bioréacteur, aussi bien qu'à court terme pendant la réinjection de lixiviat, là où les techniques de mesure et le temps sont limitants en laboratoire ou sur site
38
Muthraparsad, Namisha. "Microbial methane oxidation assessment and characterisation in bench-scale landfill bioreactors." Thesis, 2007. http://hdl.handle.net/10539/2076.
Full textAbstract:
Student Number : 9902262G -
MSc Dissertation -
School of Molecular and Cell Biology -
Faculty of ScienceAnaerobic fermentative bacteria degrade waste components in landfills where methane (CH4) and carbon dioxide (CO2) are the primary biogases emitted and methanotrophic bacteria in the cover soil oxidise the emitted CH4. Three bi-phasic bench-scale landfill bioreactors were commissioned to evaluate soil nutrient addition effects on CH4 formation and oxidation and to isolate inherent soil methanotrophs using Nitrate Mineral Salts (NMS) medium. Set A soil contained no nutrient additions, Set B soil contained 50 μM nitrate and 150 μM phosphate and Set C soil contained dried sewage cake. Bioreactors were run for a 4 week period and pH, anaerobic gas emissions, volatile fatty acids (VFA), bacterial counts and scanning electron microscopy (SEM) analyses were performed. A pilot study revealed that pH dictated the stability of methanogenesis, where increased VFA levels inhibited methanogenesis. Furthermore, it was revealed that modifications of the NMS medium were needed to enrich for methanotrophs. An in depth study showed that the Set C anaerobic reactor produced the most methane with Set B the least. The hypothesis that methane oxidation in the soil could regulate methane formation in the waste could not be conclusively observed, as a lack of aeration in the soil reactors is believed to have prevented the proliferation of methanotrophs here. No methanotrophs were successfully isolated from soil, but rather major heterotrophic bacterial interference was observed. SEM revealed the presence of rod and cocci forms of bacteria in both leachate and soil, consistent with literature reports, which indicated that the bench-scale landfill bioreactors were capable of promoting bacterial growth.
39
(9842276), Kartik Venkatraman. "Phytocapping of municipal landfills: Evaluating the performance of 21 tree species and two soil depths." Thesis, 2013. https://figshare.com/articles/thesis/Phytocapping_of_municipal_landfills_Evaluating_the_performance_of_21_tree_species_and_two_soil_depths/13433012.
Full textAbstract:
"Capping is a mandatory landfill closure procedure to isolate the waste from outside environment, mainly rain water. Clay caps are mostly expensive and often fail to limit entry of water into the waste by developing cracks due to desiccation. To reduce capping costs and to increase environmental benefits, an alternate capping system called ‘Phytocapping’ was trialled at Lakes Creek Road Landfill, Rockhampton, Australia. This system consists of a soil cover and vegetation. Soil cover stores water during rainfall events and the vegetation removes the stored water via transpiration. Trees also act as ‘rain interceptors’ by trapping certain proportion of the rainfall in their canopy. Soil and plants also contribute to reduced methane emission by supporting methanotrophs in their root zone."
40
Moreno, João Rodrigo Santos Graça Fernandes. "Effects of different aeration rate and oxygen concentrations on nitrogen removal of old waste in lab-scale simulated bioreactors landfill." Master's thesis, 2017. http://hdl.handle.net/10362/55258.
Full textAbstract:
The application of in situ aeration in bioreactor landfill is a potential method to reduce the actual emissions and the emission potential from the waste material. This is achieved by accelerating the reduction of ammonia nitrogen concentration and biodegradable organic mass matter in the landfill body.
In this study, lab-scale tests were carried out to investigate alternatives that can achieve better performances of waste stabilization and pollutants emissions, with particular focus on nitrogen compounds, regarding the current re-disposal conditions of municipal solid waste from the old Landfill of Legnago. In addition, the viability of using the oxygen concentration in the outlet gas as a dimensioning and operational parameter of in situ aeration technology was also studied.
Different air flow rates were established and adjusted over time, with the aim of creating different oxygen concentrations in the outlet gas on five simulated landfill bioreactors. One control bioreactor was operated under anaerobic conditions in order to simulate the current conditions of the waste disposal.
The anaerobic bioreactor landfill showed the highest level of leachate emissions, with the highest concentrations of COD, TOC and ammonium nitrogen. Better alternatives, in terms of nitrogen removal, were obtained by simulated aerobic bioreactors landfill.
The results showed that oxygen concentration in the outlet gas is a more proper dimensioning and operational parameter than aeration flow rate itself in order to adjust the intensity of aeration required to reach the best performance of aerobic bioreactor landfills. The best performance of aeration efficiency, in terms of ammonium nitrogen removal in the leachate regarding the amount of oxygen supplied, was obtained by the bioreactor provided with the second lowest air flow rate and with an average value of 1.3% of oxygen in the outlet gas.
41
de, Abreu Ricardo Coelho. "Facultative bioreactor landfill an environmental and geotechnical study /." 2003. http://www.uno.edu/theses/available/etd-07212003-130131/.
Full textAbstract:
Thesis (Ph.D)--University of New Orleans, 2003.Title from electronic submission form. "A dissertation ... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Engineering and Applied Sciences Program"--Dissertation t.p. Vita. Includes bibliographical references.
42
Lakshmikanthan, P. "Evaluation of the Engineering Properties of Municipal Solid Waste for Landfill Design." Thesis, 2015. http://etd.iisc.ernet.in/2005/3837.
Full textAbstract:
The objective of this thesis is to evaluate the engineering properties of Municipal Solid Waste (MSW) that are necessary in the design of landfills. The engineering properties of MSW such as compressibility, shear strength, stiffness and hydraulic conductivity are crucial in design and construction of landfills. The variation of the engineering properties with time, age and degradation are of paramount importance in the field of landfill engineering. There is a need to address the role of the engineering properties in landfill engineering as it is not apparent how the engineering characteristics vary with time. The thesis presents the results of study of the engineering properties of MSW comprehensively and develops experimental data for design of MSW landfills. The work includes the study of the index properties and the engineering properties of MSW such as compressibility, shear strength, shear modulus and damping ratio and a detailed experimental study of the bioreactor landfill. The components of settlements, variation of shear strength with respect to unit weight and particle size are determined experimentally and analyzed. The dynamic properties such as shear modulus and material damping ratio and its variation with parameters such as unit weight, load, amplitude, degradation and moisture content are studied and analyzed. The normalized shear modulus reduction curve which is used in the seismic analysis of the landfills is developed for MSW based on the experimental results and previous studies. A pilot-scale bioreactor was setup in the laboratory for long term monitoring of the settlement, temperature variation and gas production simultaneously. The parameters of interest viz, pH, BOD, COD, conductivity, alkalinity, methane and carbon-di-oxide were determined. The generated data can be effectively used in the engineered design of landfills. For a better understanding, the present thesis is divided into the following eight chapter
Chapter 1 provides a general introduction to the thesis with respect to the importance of engineering properties of MSW and presents the organization of the thesis.
Chapter 2 presents a detailed review of literature pertaining to the basic, index and the engineering properties of MSW namely compressibility, shear strength, shear modulus and damping ratio, bioreactor landfill and also the scope of the study.
Chapter 3 includes the materials and methods followed in the thesis.
Chapter 4 presents the evaluation of compressibility characteristics of MSW including the components of settlement and the settlement model parameters.
Chapter 5 presents the determination of the shear strength properties of MSW using direct shear tests and triaxial tests. The variation of the strength with respect to unit weight and the particle size is examined. The results are examined in terms of strength ratio and stiffness ratio and the implications are discussed.
Chapter 6 presents the study of the dynamic characters of MSW. The variation of the shear modulus and damping ratio with respect to unit weight, confining pressure, loading frequency, decomposition and moisture content are analyzed. Normalized shear modulus reduction and damping curves are proposed for seismic analysis. Chapter 7 presents the study of the conventional and the bioreactor landfill in a small scale laboratory setup. A large scale experimental setup is fabricated to study the characteristics of a bioreactor landfill and includes the long term monitoring and analysis of temperature, gas, settlement and leachate characteristics periodically. The results of the comprehensive study are presented in this chapter. Chapter 8 summarizes the important conclusions from the various experimental studies reported in this dissertation. Conclusions and the scope of future work are presented. A detailed list of references and the list of publications from the thesis are presented at the end. Appendix A presents the life cycle analysis and life cycle cost analysis of MSW land disposal options. The land disposal options such as open dumps, engineered landfills and bioreactor landfills are analyzed in this study.
43
Santhosh, L. G. "Reliability Based Approach for Evaluation of MSW Landfill Designs and Site Selection using GIS." Thesis, 2016. http://hdl.handle.net/2005/3203.
Full textAbstract:
Dumping of municipal solid waste (MSW) generated due to anthropogenic activities in any barren land or out fields causes severe hazards to human populations, ecosystems and the environment. In order to avoid this, it is required to design landfills in an engineered and scientific manner. Therefore, it is necessary to understand the behaviour of landfills over a period of time, to design landfills for site specific conditions. In this thesis such an attempt is made to evaluate performance of conventional landfill system using a large scale anaerobic reactor in the laboratory. The performance of the containment (bottom liner and final cover) systems is evaluated through numerical modelling and reliability based analysis. Response Surface Methodology (RSM) is used to develop linear regression models. Influence of various parameters and their uncertainty on the reliability of the containment systems are studied for various scenarios and conditions. Reliability assessment of containment systems play a decisive role in taking remedial measures in order to reduce its adverse affects on the environment and human health in the vicinity of landfill sites. On the other hand, pre-assessment of risk guides the engineers, planners and decision makers in achieving the goal of sustainable solid waste management as well as safe landfills. The thesis also includes assessment of vulnerability of groundwater to contamination, identification and ranking of suitable sites for municipal solid waste (MSW) disposal in the Bengaluru district, using remote sensing and Geographic information system (GIS) integrated with analytical hierarchy process (AHP), a multi criteria decision making tool. The study considers various land use, geological, hydrogeological and environmental factors as criteria. As a result, two most suitable locations are identified around the Bengaluru city and their descriptions are provided. Further, reliability analysis of the suitability of sites is evaluated considering criteria as random variables. The proposed reliability based approach helps the decision makers and planners to choose site locations having low probability of environmental pollution. The provided methods in the thesis can be effectively used for engineered design of landfills.
44
Sadri, Sara. "Aerobic treatment of landfill leachate using a submerged membrane bioreactor." 2005. http://hdl.handle.net/1993/20302.
Full text
45
Tanong, Kulchaya, and 古茜雅. "Fouling study on anoxic-oxic membrane bioreactor for treatment of landfill leachate." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/63597302827726853409.
Full textAbstract:
碩士嘉南藥理科技大學
環境工程與科學系暨研究所
98
An anoxic-oxic membrane bioreactor (MBR) process is presented to treating high contaminated landfill leachate from An-ding plant. The system operated with total working volume is equal to 18 L which separated into two tanks, the first tank is anoxic condition (6 L) and the second tank is oxic condition (12 L) respectively. Hydraulic retention time (HRT) was set at 2 days and sludge were discharged to maintain solid retention time (SRT) which are equal to 50 days. The study consisted of three phases. The first phase was operated without anoxic bioreactor. For the second phase operated with anoxic-oxic MBR, 1Q recirculation rate and molasses was supplied in anoxic tank as an extra carbon source for denitrification. The third stage, system had changed the recirculation rate from 1Q to 2Q. At the initial start-up stage, the operation got some problems such as foaming, sludge washed out and poor removal efficiency of chemical oxygen demand (COD) and nitrogen compound which is consider as common operation problems for biological treatment of landfill leachate. Successive reduction of organic pollutants were achieved after molasses addition, the average mixed liquor volatile suspended solids (MLVSS) and removal efficiency of organic pollutant increased obviously. The sludge in anoxic tank was increased up to the 4,550-9,100 mg/L and 6,175-12,900 mg/L on the second stage and the third stage respectivly. The sludge in oxic tank was increased up to 6,120-10,250 mg/L and 6,125-13,500 mg/L on the second stage and the third stage respectivly. The results of this study illustrated that the highest removal efficiencies of TCOD, SCOD, ammonia nitrogen (NH4+-N) and total nitrogen (TN) were 88%, 86%, 100% and 84%, respectively. The relationship between foods per mass ratio (F/M ratio), extracellular polymeric substance (EPS) production, mixed liquid suspended solid (MLSS), particle size distribution, specific cake resistance (α) and membrane pore size with modified fouling index (MFI) were found. The MFI is method to measure fouling potential in membrane system. Factors effect to membrane fouling is too complex to explain by only one parameter. The results from this experiment found that, specific cake resistance was increased when MFI increased which results from high MLSS accumulated on membrane surface and may reduce permeate flux and system performance. Also at low F/M ratio, small particle size, high EPS production, high total organic carbon (TOC) concentration in oxic-MBR all are result in high MFI value. The complex relationship between several parameters and MFI was explained by Carmen-Kozeny equation, biomass characteristic and physical operation etc.
46
Hossain, Md Sahadat. "Mechanics of compressibility and strength of solid waste in bioreactor landfills." 2002. http://www.lib.ncsu.edu/theses/available/etd-08302002-125806/unrestricted/etd.pdf.
Full text
47
Lozecznik, Stanislaw. "Hydraulic design, operation and clogging of leachate injection pipes in bioreactor landfills." 2006. http://hdl.handle.net/1993/20845.
Full text
48
Liao, Yuan-Lung, and 廖元隆. "Biostabilization assessment of MSW co-disposed with MSW incinerator bottom ash and fly ash in landfill bioreactor." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/4dkk86.
Full textAbstract:
碩士朝陽科技大學
環境工程與管理系碩士班
94
Due to the economical development, municipal solid waste (MSW) has increased to a greater amount as the increase of higher consumption and living standard in Taiwan. MSW treatment has evolved to incineration from landfill due to the difficulty of finding appropriate landfill site in Taiwan. However, residues such as bottom ash and fly ash will still remain 15 % of its original MSW volume. Therefore, residues have become another important issue and need to treat them to prevent secondary pollution in Taiwan. Bottom ash has been utilized as backfill, soil amendment, aggregate and landfill cover. Among them, landfill cover has played a major part for the utilization. However, the baseline data of landfill cover practice is still not fully understood. Thus, using bottom ash as landfill cover needs a deep theoretical and experimental investigation for the understanding of landfill mechanisms. For convenience, fly ash was tested and compared as well. For a short term simulation, six landfill bioreactors with 1 m high and 20 cm wide with working volume of 32 L were used to conduct the experiment. Among them, two was used as control bioreactors containing only the mixture of MSW and seeded sludge. The remained four ones were employed as tested bioreactors the same packing as control ones but with the designated bottom ash and fly ash added ratios of 100 and 200 g l-1 and 10 and 20 g l-1 respectively. These six bioreactors were maintained in a homeostatic oven of 35℃ suitable for the anaerobic digestion. For performance assessment of bioreactors, leachates with 100 mL were sampled for pH, conductivity, salinity, Cl-1, SO4-2 (IC) and metals analyses (ICP-OES). Another 100 mL leachates were recirculated. From the results, it showed that pHs were maintained between 6.5 and 7.5 throught the bioreactor operation with the exception of the first two weeks. 100 g l-1 bottom ash added and 10 and 20 g l-1 fly ash added bioreactors were found to enhance the gas production rate with the highest gas accumulation by 20 g l-1 fly ash added bioreactor. Released alkali metals, heavy metals and trace metals such as Ca, Mg, Ni, Co, Mo etc have been found to have potential beneficial rather than detrimental effects on MSW digestion. Thus, it indicated that proper MSW incinerator bottom and fly ash addition on MSW could increase the MSW decomposition and gas production rate and therefore increased the landfill MSW biostabilization.
49
Hejazi, Ramzi Fouad. "Oily sludge degradation study under arid conditions using a combination of landfarm and bioreactor technologies /." 2002.
Find full text
50
"Geochemical Analysis of the Leachate Generated After Zero Valent Metals Addition to Municipal Solid Waste." Master's thesis, 2019. http://hdl.handle.net/2286/R.I.54829.
Full textAbstract:
abstract: Zero-Valent Metals (ZVM) are highly reactive materials and have been proved to be effective in contaminant reduction in soils and groundwater remediation. In fact, zero-Valent Iron (ZVI) has proven to be very effective in removing, particularly chlorinated organics, heavy metals, and odorous sulfides. Addition of ZVI has also been proved in enhancing the methane gas generation in anaerobic digestion of activated sludge. However, no studies have been conducted regarding the effect of ZVM stimulation to Municipal Solid Waste (MSW) degradation. Therefore, a collaborative study was developed to manipulate microbial activity in the landfill bioreactors to favor methane production by adding ZVMs. This study focuses on evaluating the effects of added ZVM on the leachate generated from replicated lab scale landfill bioreactors. The specific objective was to investigate the effects of ZVMs addition on the organic and inorganic pollutants in leachate. The hypothesis here evaluated was that adding ZVM including ZVI and Zero Valent Manganese (ZVMn) will enhance the removal rates of the organic pollutants present in the leachate, likely by a putative higher rate of microbial metabolism. Test with six (4.23 gallons) bioreactors assembled with MSW collected from the Salt River Landfill and Southwest Regional Landfill showed that under 5 grams /liter of ZVI and 0.625 grams/liter of ZVMn additions, no significant difference was observed in the pH and temperature data of the leachate generated from these reactors. The conductivity data suggested the steady rise across all reactors over the period of time. The removal efficiency of sCOD was highest (27.112 mg/lit/day) for the reactors added with ZVMn at the end of 150 days for bottom layer, however the removal rate was highest (16.955 mg/lit/day) for ZVI after the end of 150 days of the middle layer. Similar trends in the results was observed in TC analysis. HPLC study indicated the dominance of the concentration of heptanoate and isovalerate were leachate generated from the bottom layer across all reactors. Heptanoate continued to dominate in the ZVMn added leachate even after middle layer injection. IC analysis concluded the chloride was dominant in the leachate generated from all the reactors and there was a steady increase in the chloride content over the period of time. Along with chloride, fluoride, bromide, nitrate, nitrite, phosphate and sulfate were also detected in considerable concentrations. In the summary, the addition of the zero valent metals has proved to be efficient in removal of the organics present in the leachate.Dissertation/Thesis
Masters Thesis Environmental and Resource Management 2019