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Quantificação e qualificação de resíduos gerados em um shopping center de Porto Alegre - RSFerreira, Erci Marcelo Borges January 2011 (has links)
Os grandes centros comerciais ou Shopping Centers são grandes geradores de resíduos sólidos. O que se observa na maioria dos empreendimentos são iniciativas que visam o aumento do consumo, sem a preocupação com a massa de resíduo gerado e sua destinação. Neste sentido, o presente trabalho objetiva identificar e quantificar os resíduos sólidos provenientes de um shopping center na cidade de Porto Alegre. A metodologia consiste em transportar os resíduos em veículo apropriado até o seu destino para a realização de sua segregação, quantificação e qualificação, para então ser comercializado. Verificou-se que o resíduo é composto por uma série de materiais que podem ser reutilizados. A taxa de reciclagem variou de 36 % a 56 %, enquanto que o potencial teórico ficou em torno de 94%. Os meses de maior geração de resíduos coincidem com os meses festivos e de férias de inverno, quando há um aumento do público circulante. Observou-se um aumento nos últimos anos na produção de resíduos no empreendimento, entretanto o mesmo não ocorreu na proporção de material reciclado. / The great commercial centers, or Shopping centers, are great creators of solid wastes. It is observed in most shopping centers initiatives aiming the increase in consumption, without actions in reduction of solid wastes and their destination. The present work aims to identify and to quantify the solid wastes originating from a Shopping Center in the city of Porto Alegre. The methodology consisted in transporting the waste in an appropriate vehicle for segregation, quantification and qualification, to be sold. It was found that the residue consists of a series of materials that can be reused. The recycling rate ranged from 36% to 56%, while the theoretical potential was around 94%. The months of greatest waste generation coincided with the festive months and winter holidays, when there is an increase in the circulating public. There was an increase in recent years in the production of waste, however the same increase was not found in the proportion of the recycled material.
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Estudo da separação e aproveitamento da parte metálica e de óxidos presentes no resíduo gerado no corte de rochas ornamentais. / Study of separation and reuse of metallic part and present oxides in residue generated in ornamental rocks cutting.Eduardo Junca 30 November 2009 (has links)
Este trabalho tem como objetivo o estudo do reaproveitamento da parte metálica e a caracterização dos óxidos presente no resíduo de granito gerado na etapa de desdobramento. Inicialmente, foi feita a caracterização química e física do resíduo através de análise química, difração de raios-X, microscopia eletrônica de varredura e análise granulométrica. Após a caracterização do resíduo, foi dado inicio aos processos para a recuperação do Fe metálico que envolveram: separação magnética, mesa concentradora e ciclonagem. A separação magnética foi realizada em três etapas: a primeira onde se utilizou um separador magnético a úmido de alta intensidade, onde foi utilizado apenas o campo magnético remanescente do equipamento. Na segunda etapa, onde o material magnético obtido na primeira etapa foi submetido a uma nova separação magnética manual utilizando um imã de terras raras. Na terceira etapa, o material magnético obtido com o imã de terras raras foi submetido a uma separação magnética manual com um imã ferrítico. Nos ensaios de mesa concentradora, foram realizadas variações na inclinação da mesa, freqüência de oscilação e vazão de água de lavagem. Já nos ensaios de ciclone, o parâmetro variado foi à pressão de alimentação. Foram realizadas variações nos parâmetros dos equipamentos com o intuito de se aperfeiçoar e definir os melhores parâmetros para a recuperação do Fe metálico. Após cada ensaio, foi realizada a análise química volumétrica para a determinação do teor de Fe metálico obtido em cada produto. Pelos resultados obtidos, o método de separação magnética foi a que apresentou os melhores resultados, sendo possível a obtenção de um concentrado ferroso com 93% de Fe metálico e um concentrado granítico com 0,6% de Fe metálico. Já nos ensaios de mesa concentradora, o melhor resultado obtido foi um concentrado ferroso com apenas 13,7% de Fe metálico, e nos ensaios de ciclone foi possível à obtenção de um produto com apenas 7,2% de Fe metálico. A partir do concentrado ferroso e granítico obtido na separação magnética foi realizada a caracterização através de microscopia eletrônica de varredura, difração de raios-X e análise granulométrica. A partir do concentrado ferroso obtido, foram produzidos briquetes com uso de 2% de cal hidratada como aglomerante. Foram realizados testes de resistência mecânica a verde e a seco nos briquetes produzidos. Foi obtido uma resistência mecânica a verde de no máximo 1,02 kN e a seco de no máximo 3,59 kN. / The aim of this work is to study the reuse of the metallic part and the characterization of oxides present in the waste from granite sawing. First, the chemical and physical characteristics of the waste were analyzed by chemical analysis, X-ray diffraction, scanning electron microscopy and size analysis. Procedures for the metallic iron recovery (magnetic separation, concentrator table, and cyclonic separation) were performed after the waste characterization. Magnetic separation was performed in three phases. First, using a high intensity wet magnetic separator, which only the remaining magnetic field of equipment was utilized. In the second phase, the magnetic material obtained in first phase was subjected to a new manual magnetic separation using rare earth magnets. In a third phase, magnetic material obtained with rare earth magnets was subjected to manual magnetic separation using ferrite magnets. In the experiments of concentrator table, were carried out changes in table inclination, oscillation frequency and wash water flow. For cyclone tests, the varied parameter was the water supply pressure. Variations in equipment parameters were performed in order to improve and decide the best parameters for recovery of metallic iron. After each experiment, volumetric chemical analysis was performed to determine the metallic iron content of each product. The results show that the magnetic separation method had the best results since it is possible to obtain a ferrous concentrated with 93.0 wt. % metallic iron and granite concentrated with 0.6 wt. % metallic iron. While for concentrator table tests, the best result presented a ferrous concentrated with only 13.6 wt. % metallic iron; and for cyclone tests, a product with only 7.2 wt. % of metallic iron was obtained. Ferrous and granite concentrated from magnetic separation were characterized by scanning electron microscopy, X-ray diffraction and size analysis. Using the obtained ferrous concentrated, briquettes were produced with 2 wt. % hydrated lime as binder. Produced briquettes were tested using dry and wet mechanical strength test. Wet mechanical strengths of up to 1.02kN were obtained, and a maximum of 3.59kN was registered to dry mechanical strength.
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Viabilidade de aproveitamento de resíduos de tratamento de esgotos na construção civil / Viability of harnessing of sewage treatment waste in civil constructionGasparim, José Carlos, 1961- 23 August 2018 (has links)
Orientador: Vladimir Antonio Paulon / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-23T18:58:49Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: Apesar do déficit da ordem de 50% incidente no tratamento de esgotos do país, o volume de resíduos produzidos nos grandes centros urbanos já é preocupante, em face da escassez de opções para sua destinação final. Ao passo que, foi identificada, nesses resíduos, a presença de dois materiais com características distintas, mas que apresentam potencial de reaproveitamento. São eles: uma considerável quantidade de areia introduzida no sistema durante o transporte e o próprio lodo orgânico. O aproveitamento mais prático desses materiais seria na agricultura, através de seu processamento para transformá-los em fertilizante. No entanto, as áreas mais urbanizadas, que são as maiores produtoras desses resíduos, não demandam por essa utilização, mas apresenta outras carências, como a de materiais de construção mais econômicos e de melhor qualidade. Este trabalho propõe o aproveitamento desses rejeitos na produção de materiais de construção, mais especificamente na fabricação de blocos de concreto para alvenaria; uma vez que a areia é um material tradicionalmente utilizado, como agregado, na produção de concretos e o lodo é passível de ser processado e utilizado como adição fina e, sob determinadas condições, apresentar propriedades pozolânicas. A propositura de tratamento dos rejeitos para viabilizar seu aproveitamento na construção civil envolve lavagem da areia com água de reuso e desinfecção térmica da areia e do lodo, utilizando energia de biogás produzido na própria Estação de Tratamento de Esgotos. Foram efetuados ensaios de caracterização dessas matérias primas e de blocos para alvenaria estrutural com elas produzidos, que apresentaram resultados muito promissores, indicando a possibilidade de efeitos microfiller e pozolânico do lodo tratado e vantagem na utilização da areia, devido à sua fina granulometria, além de redução de custos e eliminação de um passivo ambiental, o que viabilizaria, inclusive, a criação de uma linha de produção / Abstract: Despite the deficit of the order of 50% incident in sewage treatment in the country, the volume of waste generated in urban centers already is worrying, given the dearth of options to its final destination. Whereas been identified, these residues, the presence of two materials with different characteristics but which have a potential reuse. They are: a considerable amount of sand introduced into the system during transport and even the organic sludge. The use of these materials would be more practical in agriculture, through its processing to turn them into fertilizer. However, the more urbanized areas, which are major producers of such waste, no demand for that use, but have other needs, such as building materials cheaper and of better quality. This paper proposes the use of such wastes in the production of building materials, more specifically in the manufacture of concrete blocks for brickwork; since sand is a material traditionally used as aggregate in concrete production and the sludge is liable to be processed and used as a fine addition and under certain conditions, exhibit pozzolanic properties. The initiation of treatment of the tailings to enable their use in construction involves washing the sand with water reuse and thermal disinfection of sand and silt, using biogas energy produced on the Sewage Treatment Station. Characterization tests were made of these raw materials and for structural masonry blocks produced with them, which showed very promising results, indicating the possibility of microfiller and pozzolanic effects of treated sludge and advantage of using sand, due to its fine particle size, and cost reduction and elimination of environmental liability, which would enable even the creation of a production line / Mestrado / Saneamento e Ambiente / Doutor em Engenharia Civil
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Determinação da condutividade hidráulica e análise química do lixiviado de resíduos sólidos urbanos utilizando permeâmetros de grandes dimensões / Determination of hydraulic conductivity and chemical analysis of municipal solid waste leachate using large dimensions permeametersMortatti, Bruno Cesar, 1985- 09 June 2013 (has links)
Orientador: Sueli Yoshinaga Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-23T20:11:00Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: Dois permeâmetros de carga constante e grandes dimensões, com 0,057 e 0,042 metros cúbicos, respectivamente, foram utilizados em laboratório, sob condições controladas, para as determinações das condutividades hidráulicas saturadas de Resíduos Sólidos Urbanos (RSU) coletados no Aterro Sanitário Delta A, localizado na cidade de Campinas-SP. Duas fases experimentais foram delineadas envolvendo diferentes parâmetros como composição gravimétrica e grau de compactação. Para cada fase experimental foram realizados vários ensaios para as determinações das condutividades hidráulicas saturadas em função dos tempos de operação dos permeâmetros e levantamento das principais variáveis físicas envolvidas neste processo, como teor de umidade, capacidade de campo, carga hidráulica e vazão. Simultaneamente, os lixiviados oriundos de cada ensaio realizado foram coletados e monitorados pelas análises dos principais parâmetros e espécies químicas para avaliação das etapas envolvidas no processo de biodegradação dos RSU. As condutividades hidráulicas saturadas, determinadas nos ensaios realizados, variaram de 1,6E-02 a 5,7E-05 m/s em função dos diferentes graus de compactação. Algumas variáveis químicas se mostraram eficientes na identificação das etapas de biodegradação, como potencial redox, ácidos orgânicos voláteis, nitrogênio amoniacal, acetato e carbono total dissolvido. O comportamento dessas variáveis em função dos tempos de operação permitiu a identificação das etapas acidogênica/acetogênica na biodegradação dos RSU / Abstract: Two constant load and large dimensions permeameters, with 0.057 and 0.042 cubic meters, respectively, were used in laboratory, under controlled conditions, for the determination of saturated hydraulic conductivity of Municipal Solid Waste (MSW) collected in the Delta A Sanitary Landfill, located at city of Campinas-SP. Two experimental phases were outlined involving different parameters such as gravimetric composition and degree of compression. For each experimental phase were carried out various tests for the determination of satured hydraulic conductivity as a function of the operation times of the permeameters and physical survey of the main variables involved in this process, such as, moisture content, field capacity, hydraulic head and volumetric flow rate. Simultaneously, the leachates coming of each test performed were collected and monitored by the analysis of the main parameters and chemical species for evaluation of the steps involved in the biodegradation of MSW. The saturated hydraulic conductivities, determined in tests, ranged from 1.6E-02 to 5.7E-05 m/s for different degrees of compression. Some chemical variables such as redox potential, volatile fatty acids, ammoniac nitrogen, acetate and dissolved total carbon, were effective in identifying the stages of biodegradation. The behavior of these variables as a function of time of operation allowed the identification of the acidogenic/acetogenic steps in the biodegradation of the MSW / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências
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NON-INVASIVE CHARACTERIZATION OF UNSATURATED ZONE TRANSPORT IN DRY COAL ASH DUMPS: A CASE STUDY OF TUTUKA, SOUTH AFRICAMuchingami, Innocent I. January 2013 (has links)
Doctor Scientiae / The management of the large volumes of solid wastes produced as coal combustion
residue is of particular concern due to the presence of leachable metals and salts which
may constitute a long term environmental risk and potential contamination of both
surface and groundwater systems of the surrounding environment. In order to
implement an efficient monitoring scheme and to assess the impact of the ash dump on
the hydrologic system, a thorough knowledge on the migration of solutes fluxes in dry
ash dumps as well as the controls on the transport of these solutes to the underlying
groundwater system is required.
The conventional methods which have been widely used for such applications are
centred on extracting and analysing several samples from observation wells are drilled
on the dump. This has however created a potentially hazardous situation as the
installation of monitoring wells may result in the creation of new fluid pathways and
results in further migration of leachates. Nevertheless, non–invasive characterization
has often been useful in the determination of subsurface hydraulic properties and is a
key step towards the solution of real-life problems in hydrology, hydrogeology and soil
science. In contaminant transport non-invasive methods have often proved to be an
efficient tool as compared to traditional drilling and sampling techniques which in most
cases results in the creation of preferential flow paths and do not allow for the space
and time resolution needed for the monitoring of hydrological and environmental
processes.
In this context, this study seeks to develop a generic conceptual model for the ash
dump through the use of non-invasive geophysical techniques and numerical modelling techniques at the Tutuka Ash dump, Mpumalanga South Africa. Changes in electrical
resistivity were used correlate changes in moisture contents during moisture and salt
leachate ingression in ash dumps with a sufficient accuracy. A determination of the
suitability of Archie‘s law to describe the relationship between electrical resistivity and
solute transport ash medium was achieved through empirical laboratory experiments.
Electrical resistivity tomography was then used as an appropriate tool for the elucidation
of potential flow paths and brine dispersion in the ash dump. The flow rates through the
ash dump were estimated by considering the rate of brine injection and the distance
travelled by the brine plume over the time spanned in time lapse infiltration experiments.
Additional geophysical profiles managed to show the lithostratigraphy of underlying
hydro-geology, thereby ensuring that the knowledge of the geology can be established
without the application of any intrusive methods.
To ensure that development of the conceptual model of the unsaturated zone transport
of the ash dump was developed with sufficient accuracy, numerical models were also
used to describe solute transport in the vadose zone. The HYDRUS2D numerical
package was used simulate the flux dynamics within the unsaturated zone of the coal
ash medium, so as to develop a conceptual understanding of water flow and salt
transport through the unsaturated zone of the coal ash medium. The results from the
study suggested a conceptual solute transport model that consists of a two layers. The
upper layer represented the unsaturated zone of the ash dump which was the source of
any potential contaminant transport that could be of concern. The lower layer describe
the underlying the subsurface environment to the ash dump which include the soil zone,
the shallow aquifer and the deep fractured rock aquifer. To enable this conceptualisation, results from the numerical simulations and
geophysical interpretations of the electrical resistivity profiles were the critical
components for optimising the site-specific subsurface water flow and solute transport
processes, as well as producing the most acceptable conceptualisation of the ash dump
system that could be used in hazard assessment and mitigation against potential
groundwater pollution. The conceptual models developed in this study proposed an
explanation on impact of the ash dump to the hydro-geologic and the eco-hydrologic
environment by proposing a scenario of contamination of the underling ash dump and
the existing. In this regard, the study managed to provide important scenarios that may
be necessary during mitigation procedures for both the ash dump and the wetland.
Key words: non-invasive, coal ash, time lapse, electrical resistivity tomography,
numerical models, HYDRUS2D, conceptual model.
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The impacts of low levels of antibiotics on freshwater microbial communitiesAres, Maria Elena January 1999 (has links)
No description available.
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Low-cost adsorbents from industrial wastesPollard, Simon J. T. January 1990 (has links)
No description available.
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Lead minerals in soils contaminated by mine-waste : implications for human healthCotter-Howells, Jane January 1991 (has links)
No description available.
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Assessment of Leachate Characteristics and Geotechnical Properties of Municipal Solid Waste LandfillNaveen, B P January 2016 (has links) (PDF)
Solid Waste Management is one of the essential services provided by local bodies to keep the urban areas clean. Often it is poorly rendered as it is unscientific, out-dated and inefficient. With the rapid increase in population, livening standards, the generation rates of solid waste are increasing drastically. The landfill waste includes both organic and inorganic wastes as it is not often effectively segregated before disposal. The problem is acute in developing countries such as India. Bangalore city, with a population of about 10.18 million and more than 2000 industries, generates about 4,500 TPD of municipal solid waste. Of this Presently, various municipal solid waste processing units in Bangalore can handle only about 2100 TPD of waste. Mavallipura landfill developed and operated by M/s. Ramky Environmental Engineers, located 40 km away from Bangalore, is being used for disposing of about 1000 TPD, the installed capacity being only 600 TPD of waste. There are also a few dumps in around Bangalore due to historical reasons and insufficient capacity of various designated landfills.
To reclaim the old dump sites/closed landfill sites for infrastructural development, it is necessary to know their geotechnical characteristics. Within the Landfill, the characteristics of the waste may change with depth due to degraded wastes as it has been dumped over a period of time. The physical parameters, chemical properties as well as the geotechnical behaviour of the waste change with depth. MSW is known to be a heterogeneous material of varying constituent types and dimensions, containing elements that degrade with time. To consider MSW as a geo-material to support the foundation of structures such as buildings and pavement, an analysis of the bearing capacity of the foundation and further long-term settlement of MSW is essential. The MSW samples are retrieved from a Mavallipura landfill site, Bangalore and analysed for important geotechnical properties such as compaction characteristics, shear strength, permeability, compressibility behaviour and dynamic properties of MSW using ultrasonic and cyclic triaxial tests. This research thus aims to provide valuable information about landfill sites for reclamation, closure and infrastructural development after the closure of landfills. Scanty data are available on the geotechnical properties of waste from landfill sites with varying degrees of degradation. This landfill site is selected as there is a huge environmental concern regarding the soil and groundwater contamination in the area and also can represent a typical landfill scenario in tropical regions.
Quantification, quality assessment, consequent treatment and management of leachate have become a monstrous problem world over. In this context, the present study envisages to study the physicochemical and biological characterization of representative urban municipal landfill leachate and nearby water bodies and attempts to figure out relationships between the various parameters together with understanding the various processes for chemical transformations. The analysis shows intermediate leachate age (5-10 years) with higher nutrient levels i.e. 10,000 - 12,000 mg/l and ~2,000 - 3,000 mg/l of carbon (COD) and nitrogen (TKN) respectively. Elemental analysis and underlying mechanisms reveal chemical precipitation and co-precipitation as the vital processes in leachate pond systems resulting in accumulation of trace metals in these systems. The microbial analysis also correlated with specific factors relevant to redox environments that show a gradient in nature and the abundance of biotic diversity with a change in leachate environment. Finally, the quality and the contamination potential of the sampled leachate were performed with the help of potential leachate index (LPI) analysis and water quality index (WQI) analysis for surrounding water bodies (namely surface pond and open well) of Mavallipura landfill site.
A geotechnical testing program has been drawn to evaluate the engineering properties of municipal solid waste samples retrieved from a landfill at Mavallipura at various depths through augur within the landfill dumped area. Laboratory studies included are composition, moisture content, particle size analysis, compaction, permeability, direct shear test, consolidation, triaxial compression test. For the laboratory tests, we had considered maximum particle sizes of less than 4.75 mm only. Standard Proctor Compaction tests
yielded a maximum dry density of 7.0kN/m3 at 50% optimum moisture content. The permeability of MSW results shows in the range of 4x10-4 cm/sec. Compression index of MSW is 0.46980 and recompression index of MSW is 0.09454. Results obtained from the rectangular hyperbola method are compared with Casagrande and Taylor methods to prove that this method is reliable equally, and results are reasonably accurate. Based on direct shear tests, the MSW sample exhibited continuous strength gain with an increase in shear strain (16%) to define strength. The cohesion of MSW was 10kPa and friction angle is 34°. Based on the elastic constants results obtained from the direct shear test found to be very soft material. In the triaxial test, the MSW sample exhibited continuous strength gain with an increase in axial strain. The frictional component is increased due to sliding and rolling of fibrous particles over one another resulting in the development of apparent cohesion due to antiparticle bonds within the MSW material.
Landfills are an integral part of waste management, and disastrous consequences can happen if seismic vulnerability of these landfills is not considered. Dynamic properties of MSW are required to perform seismic response analysis of MSW landfills, but there is no good understanding of the dynamic shear strength of MSW in literature. A comprehensive laboratory cyclic triaxial testing program has been taken up to determine the properties at different densities, confining pressures and shear strains. MSW degrades with time, and its shear modulus and damping are expected to vary with time and degradation. For the density of 6 kN/m3 the dynamic shear modulus values for MSW varied from 0.68 MPa to 5.38 MPa and damping ratio varied from 20% to 40% for MSW. For the density of 7 kN/m3 the dynamic shear modulus values for MSW varied from 1.8 MPa to 7.5 MPa and Damping ratio
varied from 23% to 40% for MSW. For the density of 8kN/m3 dynamic shear modulus values for MSW varied from 2.46 MPa to 8.00MPa and damping ratio varied from 16% to 33% for MSW. Also, the ultrasonic testing method was used for determining the dynamic properties at low strains. The Ultrasonic test results indicated that with an increase in density of the sample and with decreased void ratio, the pulse propagation velocity (Vp) increases. With an increase in the density, the shear wave velocity and elastic constants (elastic modulus and shear modulus) increase. The elastic constant values obtained from the ultrasonic test are higher compared to values obtained from unconsolidated-undrained triaxial tests. Also, the carbon stored in the buried organic matter in Mavallipura landfill is estimated. Total organic carbon increases steeply with an increase in depth and is significantly high at a depth of 6 m. Subsurface properties cannot be specified but must be analysed through in-situ tests. The in-situ testing that are carried out in a landfill are boring, sampling, standard penetration test (SPT), dynamic cone penetration test (DCPT) and plate load tests (under static and cyclic condition). A correlation between corrected SPT ‘N’ values and measured using shear wave velocities has been developed for Mavallipura landfill site. Results show that the corrected SPT- N values increase with depth. Corrected N-values are used in the landfill design, so they are consistent with the design method, and correlations are useful. The results obtained from the dynamic cone penetration tests shows lower value when to compare with standard penetration test. The unit weight profile with depth ranged from a low unit weight of 2.48 kN/m3 near the surface to a highest value of approximately 9.02 kN/m3 at a depth of 6 m. The highest temperatures for landfills were reported at mid-waste elevations with temperatures decreasing near the top. The bearing pressure-settlement curves for plate size 75cm and 60cm presented similar behaviour while the plate size of 60cm curve presents a lesser settlement of 70mm, compared to with plate size of the 75cm curve with the settlement of 80mm and failure mode could be classified as punching shear. The cyclic plate load test with plate size of 60cm and 75cm were carried out on the soil cover. The elastic constants were found to be 73.87 and 96.84 kPa/mm and for 60 and 75cm plates respectively. Geophysical testing may not be as precise but has the benefit of covering large areas at small costs and sometimes can locate features that might be missing by conventional borings. Multichannel analysis of surface waves (MASW) is an indirect geophysical method used in the landfill for the characterization of the municipal solid waste site. The Mavallipura landfill was surveyed up to the length of about 35m at the top level. A series of one-dimensional and two-dimensional MASW surveys used active seismic sources such as sledgehammer (5kg) and propelled energy generator (PEG-40) was used. This hammer was instrumented with geophones to trigger record time. All the testing has been carried out with geophone spacing of 1m and recorded surface wave arrivals using the source to first receiver distance as 5m with recording length of 1000 millisecond and the recording sampling interval of 0.5 milliseconds (ms) were applied. Results shows that the PEG-40 hammer can generate the longest wavelength with a maximum depth of penetration. The shear wave velocity varies from 75 to 155 m/s with an increase in depth of about 27.5m. Based on the site characterization at the landfill site, it was found that the Mavallipura landfill site can be categorized as very loose, and it is still in a continued stage of degradation. Shear wave and P-wave velocity profile for eight major locations in the study area were determined and variation of waste material stiffness corresponding to the in-situ state with depth, was also evaluated. Also, MASW survey has been carried out to develop dispersion curve on another landfill site at Bhandewadi, Nagpur. MASW system consisting of 24 channels geode seismograph with 24 geophones of 4.5Hz capacity is used in this investigation. The seismic waves were created by sledgehammer with 30cmx 30cmx2cm size hammer plate with ten shots. These waves were captured by the geophones/receivers and further analyzed by inversion. The results indicated that near surface soils(less than 3m depth) approximately the to 5mm, and with 85% of dry weight basis of waste particles with sizes less than 10mm, the shear wave velocity varies from 75 to 140 m/s (frequency ranges from 30 to 23Hz). With the increase in 6.5m depth, the shear wave velocity ranged from 140 to 225m/s (frequency ranges 23 to 13Hz). Overall, the results of the study showed that seismic surveys have the potential to capture the changes in dynamic properties like shear wave velocity and Poisson’s ratio of the depth of MSW landfill to infer the extent of degradation and provide dynamic properties needed for seismic stability evaluations.
Based on the in situ and laboratory results of this study and a review of the literature, the unit weight, shear wave velocity, strain-dependent normalized shear modulus reduction and material damping ratio relationships for Mavallipura landfill are developed and also validated using semi-empirical methods. Finally, seismic response analysis of Mavallipura landfill has been carried out using the computer programs like SHAKE 2000 and DEEPSOIL. Results show that the unit weight is increased with depth in response to the increase in overburden stress. The proposed material damping ratio and normalized shear modulus reduction curve lie close to the profile given in the literature for landfills composed of waste materials with 100% particles sized less than 20mm. Peak spectral acceleration at 5% damping value is 0.7g for 0.07 sec in SHAKE 2000 and peak spectral acceleration at 5% damping value is 0.63g for 0.04 sec in DEEPSOIL. Amplification ratio is 6.11 at 1.1l Hz in SHAKE2000 and 4.65 at 2.67Hz in DEEPSOIL. Peak ground acceleration (PGA) for the landfill site, it is observed PGA has decreased from 0.3g to 0.15g in DEEPSOIL and PGA has decreased from 0.33g to 0.15g in SHAKE2000.
The studies presented in the thesis brought out the importance of characterization of municipal solid waste leachate regarding metabolism and treatment/degradation of Mavallipura landfill leachate. For municipal solid waste of with sizes ranging from 0.08
coefficient of permeability being about 10-4 cm/sec, the compression index was about 0.47. A more reliable method of calculating the coefficient of consolidation has been recommended. Correlations between shear wave velocity and SPT-N values has been developed for the Mavallipura landfill site. The results showed that the dynamic cone penetration tests values are lower than indicated by standard penetration tests. The cyclic plate load tests carried out with plate sizes of 75cm and 60cm showed that elastic constants of 96.84 kPa/mm and 73.87kPa/mm respectively. MSW properties evaluated in this thesis are compared with those of soft clays. The MSW properties showed higher values (strength and SBC) and lower values of compressibility, compared with those of soft clays. Thus foundation improvement on MSW is less challenging than foundations on soft soils. Also stabilization of MSW with other solid wastes such as fly ash can be considered as an economical option.
Based on detailed studies the importance of unit weight, shear wave velocity, strain-dependent normalized shear modulus reduction and material damping ratio relationships for landfill waste have been developed. Based on the site characterization, the waste landfill has been categorized as very loose material, which is still in a degradation process. SHAKE2000 software shows higher PGA value comparing with DEEPSOIL.
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CRITICAL EVALUATION OF LEACHATE CLOGGING POTENTIAL IN GRAVITY COLLECTION SYSTEMS AND MANAGEMENT SOLUTIONSUnknown Date (has links)
Leachate clogging in the Leachate Collection System (LCS) due to chemical precipitations and biofilms produced by microbial activities is a common phenomenon in any Municipal Solid Waste (MSW) landfill. This study focuses on quantifying the factors that impact the micro-environment of leachate; and microbial activities that help the precipitates to form and attach to the LCS. It also evaluates the performance of operational changes that have been implemented or the potential alternatives and recommends the possible measures to reduce the severity of clogging. A field scale side-by-side pipe network, and several laboratory setups were used in this study. Calcite is identified to be the predominant phase present in the precipitates using XRD/XRF analysis which, concur with the previous studies. Microbial growth and activities enhance the precipitation of CaCO3 in LCS. Clogging in LCS pipes can be controlled if not eliminated by continuous monitoring along with frequent cleaning with physiochemical processes. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
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