• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 7
  • 1
  • 1
  • Tagged with
  • 9
  • 9
  • 6
  • 5
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Detecção da influencia da vinhaça na resistividade do solo atraves da analise de dados geofisicos : um estudo de caso no assentamento Sepe, Tiaraju, SP / Vinasse influence detection in soil electrical resistivity by geophysics data analysis : a case study at Sepe, Tiaraju, settlement of landless agricultural laborers, SP

Cruz, Juliana Igarashi da 22 August 2008 (has links)
Orientadores: Rodrigo de Souza Portugal, Carmen Hernandez Lucendo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-11T23:00:54Z (GMT). No. of bitstreams: 1 Cruz_JulianaIgarashida_M.pdf: 7217900 bytes, checksum: 29ff36fe80ce1106d1c88e973330783b (MD5) Previous issue date: 2008 / Resumo: A vinhaça, resíduo gerado na proporção de 13 litros para cada litro de álcool produzido, possui um alto potencial poluidor dos recursos hídricos subterrâneos e superficiais, causa alterações no comportamento do solo e pode gerar problemas de salinização. Este trabalho objetiva avaliar a eficiência do método da eletrorresistividade para a detecção e mapeamento das anomalias causadas pela disposição inadequada de grandes quantidades de vinhaça em um antigo tanque de infiltração localizado no Assentamento Sepé- Tiarajú, Municípios de Serrana e Serra Azul - SP. O trabalho objetiva também caracterizar o tipo de anomalia inerente ao resíduo no local estudado e diagnosticar sua influência dentro e fora dos limites do tanque. Foram executados onze perfis de tomografia elétrica, arranjo dipolo-dipolo radial e espaçamento entre eletrodos de 10 metros. Os ensaios geofísicos mostraram que o método da eletrorresistividade é apropriado para mapear as anomalias decorrentes da disposição de grandes quantidades de vinhaça no solo, apontar suas áreas de influência e concluir que a contaminação extrapola os limites do tanque. A influência da vinhaça pode ser caracterizada por baixos valores de resistividade entre 10 Ohm.m e 90 Ohm.m, podendo o seu comportamento ser comparado ao do chorume, que também é bastante condutivo. / Abstract: The vinasse, a waste produced in the proportion of 13 liters for each liter of alcohol. It has a high potential of polluting groundwater and superficial water resources, changes the soil behaviour and can also develop sanilization problems. This work aims to evaluate the efficiency of the DC-resistivity method in detecting and mapping anomalies caused by, inappropriate disposal of vinasse in an inactive infiltration tank located at "Sepé- Tiarajú" settlement of landless agricultural laborers in the Ribeirão Preto region. Besides, as secondary goals, this work aims to characterize the type of anomaly residue as well as to diagnose its influence inside and outside of the limits of the tank. Eleven electrical resistivity tomography profiles were carried out with the dipole-dipole array, 10m of dipoles length and 5 levels of investigtion. The geophysical survey enabled us to conclude. that the dc-resistivity method is appropriate for mapping the contamination plume caused by intense vinasse disposal and its influence. It enabled also to conclude that the contamination exceeds the tank limits. The vinasse influence can be characterized by low resistivity values between 10 Ohm.m and 90 Ohm.m and its behavior can be compared with the one of the chorume, which is also conductive. / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências
2

Cobre, zinco, manganês e sódio em rações, dejetos líquidos de suínos e solos de áreas de uso agrícola / Copper, zinc, manganese and sodium in food, liquid waste of pigs and soils in areas of farm land use

Santos, Rosele Clairete dos January 2014 (has links)
A aplicação sistemática de dejetos líquidos de suínos (DLS) em solos agrícolas pode aumentar os teores totais de metais e suas formas biodisponíveis. Este trabalho teve como objetivo avaliar o impacto em solos agrícolas resultante da aplicação de dejetos líquidos de suínos (DLS) provenientes de duas fases de criação (terminação e creche). Os estudos foram conduzidos no município de Arroio do Meio/RS. Foram coletadas amostras de rações, de DLS e de solos nas profundidades de 0-0,025, 0,025-0,05, 0,05-0,10, 0,10-0,20 e 0,20-0,40 m em propriedades suinícolas do município. As análises realizadas indicaram que há diferenças significativas entre as composições das rações fornecidas aos suínos e que os teores de Cu, Mn, Na e Zn são maiores que os sugeridos pela bibliografia especializada. A aplicação dos dejetos, de ambas as fases de criação, não aumentou, significativamente, o teor de matéria orgânica dos solos nas áreas amostradas. Os teores de P, K e Na apresentaram diferenças significativas na camada de 0 – 0,025 m nas áreas em que foram aplicados DLS da fase terminação. Os teores de Cu biodisponível foram maiores na camada de 0 – 0,05 m e os de Zn biodisponível na camada de 0 – 0,025 m. As concentrações de Mn biodisponível foram altas até a profundidade de 0,40 m. Os órgãos ambientais responsáveis pelo licenciamento das atividades suinícolas limitam o volume de DLS a aplicar em cada propriedade em 50 m3 ha-1 ano-1, não havendo exigências específicas quanto aos atributos do solo onde será aplicado e a origem do DLS. / The systematic application of pig slurry (DLS) in agricultural soils may increase the total concentration of metals and their bioavailable forms. This study aimed to assess the impact on agricultural land resulting from the application of pig slurry (DLS) from two phases (nursery and finishing). The studies were conducted in Arroio do Meio/ RS. Samples of food, DLS and soil at depths of 0- 0.025, 0.025-0.05, 0.05-0.10, 0.10-0.20 and 0.20-0.40 m were collected on farms pigs of the municipality. The analyzes indicated that there are significant differences between the compositions of the rations provided to pigs and that the contents of Cu, Mn, Na and Zn are higher than those suggested by international literature. The application of manure, from both phases of creation, did not significantly increased the organic matter content of soils in the sampled areas. The P, K and Na showed significant differences in the 0-0,025 m in areas that were applied DLS from the termination phase. The levels of bioavailable Cu was higher in layer 0-0.05m and bioavailable Zn in the layer of 0-0,025m. The concentrations of bioavailable Mn were high to a depth of 0.40m. Environmental agencies responsible for the licensing of pig activities limit the volume of DLS to apply in each property at 50 m3 ha-1 yr-1 and there are no specific requirements of the attributes of the soil where it will be applied and the source of the DLS.
3

Cobre, zinco, manganês e sódio em rações, dejetos líquidos de suínos e solos de áreas de uso agrícola / Copper, zinc, manganese and sodium in food, liquid waste of pigs and soils in areas of farm land use

Santos, Rosele Clairete dos January 2014 (has links)
A aplicação sistemática de dejetos líquidos de suínos (DLS) em solos agrícolas pode aumentar os teores totais de metais e suas formas biodisponíveis. Este trabalho teve como objetivo avaliar o impacto em solos agrícolas resultante da aplicação de dejetos líquidos de suínos (DLS) provenientes de duas fases de criação (terminação e creche). Os estudos foram conduzidos no município de Arroio do Meio/RS. Foram coletadas amostras de rações, de DLS e de solos nas profundidades de 0-0,025, 0,025-0,05, 0,05-0,10, 0,10-0,20 e 0,20-0,40 m em propriedades suinícolas do município. As análises realizadas indicaram que há diferenças significativas entre as composições das rações fornecidas aos suínos e que os teores de Cu, Mn, Na e Zn são maiores que os sugeridos pela bibliografia especializada. A aplicação dos dejetos, de ambas as fases de criação, não aumentou, significativamente, o teor de matéria orgânica dos solos nas áreas amostradas. Os teores de P, K e Na apresentaram diferenças significativas na camada de 0 – 0,025 m nas áreas em que foram aplicados DLS da fase terminação. Os teores de Cu biodisponível foram maiores na camada de 0 – 0,05 m e os de Zn biodisponível na camada de 0 – 0,025 m. As concentrações de Mn biodisponível foram altas até a profundidade de 0,40 m. Os órgãos ambientais responsáveis pelo licenciamento das atividades suinícolas limitam o volume de DLS a aplicar em cada propriedade em 50 m3 ha-1 ano-1, não havendo exigências específicas quanto aos atributos do solo onde será aplicado e a origem do DLS. / The systematic application of pig slurry (DLS) in agricultural soils may increase the total concentration of metals and their bioavailable forms. This study aimed to assess the impact on agricultural land resulting from the application of pig slurry (DLS) from two phases (nursery and finishing). The studies were conducted in Arroio do Meio/ RS. Samples of food, DLS and soil at depths of 0- 0.025, 0.025-0.05, 0.05-0.10, 0.10-0.20 and 0.20-0.40 m were collected on farms pigs of the municipality. The analyzes indicated that there are significant differences between the compositions of the rations provided to pigs and that the contents of Cu, Mn, Na and Zn are higher than those suggested by international literature. The application of manure, from both phases of creation, did not significantly increased the organic matter content of soils in the sampled areas. The P, K and Na showed significant differences in the 0-0,025 m in areas that were applied DLS from the termination phase. The levels of bioavailable Cu was higher in layer 0-0.05m and bioavailable Zn in the layer of 0-0,025m. The concentrations of bioavailable Mn were high to a depth of 0.40m. Environmental agencies responsible for the licensing of pig activities limit the volume of DLS to apply in each property at 50 m3 ha-1 yr-1 and there are no specific requirements of the attributes of the soil where it will be applied and the source of the DLS.
4

Cobre, zinco, manganês e sódio em rações, dejetos líquidos de suínos e solos de áreas de uso agrícola / Copper, zinc, manganese and sodium in food, liquid waste of pigs and soils in areas of farm land use

Santos, Rosele Clairete dos January 2014 (has links)
A aplicação sistemática de dejetos líquidos de suínos (DLS) em solos agrícolas pode aumentar os teores totais de metais e suas formas biodisponíveis. Este trabalho teve como objetivo avaliar o impacto em solos agrícolas resultante da aplicação de dejetos líquidos de suínos (DLS) provenientes de duas fases de criação (terminação e creche). Os estudos foram conduzidos no município de Arroio do Meio/RS. Foram coletadas amostras de rações, de DLS e de solos nas profundidades de 0-0,025, 0,025-0,05, 0,05-0,10, 0,10-0,20 e 0,20-0,40 m em propriedades suinícolas do município. As análises realizadas indicaram que há diferenças significativas entre as composições das rações fornecidas aos suínos e que os teores de Cu, Mn, Na e Zn são maiores que os sugeridos pela bibliografia especializada. A aplicação dos dejetos, de ambas as fases de criação, não aumentou, significativamente, o teor de matéria orgânica dos solos nas áreas amostradas. Os teores de P, K e Na apresentaram diferenças significativas na camada de 0 – 0,025 m nas áreas em que foram aplicados DLS da fase terminação. Os teores de Cu biodisponível foram maiores na camada de 0 – 0,05 m e os de Zn biodisponível na camada de 0 – 0,025 m. As concentrações de Mn biodisponível foram altas até a profundidade de 0,40 m. Os órgãos ambientais responsáveis pelo licenciamento das atividades suinícolas limitam o volume de DLS a aplicar em cada propriedade em 50 m3 ha-1 ano-1, não havendo exigências específicas quanto aos atributos do solo onde será aplicado e a origem do DLS. / The systematic application of pig slurry (DLS) in agricultural soils may increase the total concentration of metals and their bioavailable forms. This study aimed to assess the impact on agricultural land resulting from the application of pig slurry (DLS) from two phases (nursery and finishing). The studies were conducted in Arroio do Meio/ RS. Samples of food, DLS and soil at depths of 0- 0.025, 0.025-0.05, 0.05-0.10, 0.10-0.20 and 0.20-0.40 m were collected on farms pigs of the municipality. The analyzes indicated that there are significant differences between the compositions of the rations provided to pigs and that the contents of Cu, Mn, Na and Zn are higher than those suggested by international literature. The application of manure, from both phases of creation, did not significantly increased the organic matter content of soils in the sampled areas. The P, K and Na showed significant differences in the 0-0,025 m in areas that were applied DLS from the termination phase. The levels of bioavailable Cu was higher in layer 0-0.05m and bioavailable Zn in the layer of 0-0,025m. The concentrations of bioavailable Mn were high to a depth of 0.40m. Environmental agencies responsible for the licensing of pig activities limit the volume of DLS to apply in each property at 50 m3 ha-1 yr-1 and there are no specific requirements of the attributes of the soil where it will be applied and the source of the DLS.
5

Valores de referência de metais pesados em solos de Mato Grosso e Rondônia / Reference Values for heavy metals in soils from Mato Grosso and Rondônia states, Brazil

Santos, Sabrina Novaes dos 10 June 2011 (has links)
Os órgãos de monitoramento ambiental necessitam de indicadores de referência para a avaliação continuada dos impactos ambientais. Indicadores são obtidos por meio da comparação dos teores totais de elementos tóxicos de um solo com valores determinados em condições naturais (não poluídos) ou com valores de referência. No Brasil, com a crescente demanda social pela melhoria e manutenção da qualidade ambiental, alguns estudos foram realizados com o objetivo de estabelecer valores orientadores para metais pesados em solos. Estes são valores préestabelecidos quanto à presença de substâncias químicas que possibilitam a verificação de possível contaminação. A legislação brasileira estabelece três valores orientadores: Valores de Referência de Qualidade (VRQs), de Prevenção (VP) e de Investigação (VI). O VRQ indica o limite de qualidade para um solo considerado limpo a ser utilizado em ações de prevenção da poluição do solo e no controle de áreas contaminadas. Foram coletadas amostras de solo dos estados de Mato Grosso e Rondônia, nas profundidades de 0-5, 5-10, 10-20 e 20-30 cm, em áreas de vegetação nativa (sem ou mínima intervenção antrópica). Objetivou-se com essa dissertação: (i) determinar os valores de referência de metais pesados em solos de Mato Grosso e Rondônia; (ii) avaliar métodos de extração de teores pseudototais de metais pesados (EPA 3051 e Água Régia); (iii) correlacionar estes valores com atributos físicos e químicos dos solos; (iv) correlacionar os resultados desse estudo com valores já estabelecidos para solos de outros estados brasileiros. Partiu-se das hipóteses: i) não ocorrerão diferenças entre os teores naturais de metais pesados nos solos de Mato Grosso e Rondônia pelos dois métodos de extração de teores pseudototais de metais; ii) os VRQ de metais pesados para os solos de Mato Grosso e Rondônia são diferentes dos VRQ obtidos para solos de outros estados brasileiros; e iii) haverá correlação significativa entre os teores naturais de metais pesados e os atributos físicos e químicos dos solos. Houve diferença entre os métodos da água régia e EPA 3051 para recuperação dos metais Co, Ni, Pb e Zn, sendo a água régia o método que mais extraiu esses elementos, enquanto os teores de Cr e de Cu não diferiram entre os métodos. A água régia, em geral, apresentou maiores recuperações dos teores pseudototais de metais pesados nos solos. Os teores dos óxidos de Fe e Mn foram as variáveis que, de forma geral, mais correlacionaram com os metais pesados. O teor de carbono orgânico não contribuiu para avaliação da variação geral dos teores de metais por não correlacionar significativamente com nenhuma variável. As variações encontradas entre os teores de metais pesados dos solos do mundo e de outros estados brasileiros reafirma a necessidade da obtenção de valores de referência para cada estado ou para cada tipo de solo, dependendo da variação das características geomorfológicas, pedológicas e geológicas do estado. / Environmental monitoring institutions need benchmarks for continuous assessment of environmental impacts. Indicators are obtained by comparing the total levels of toxic elements in soils with values determined in natural conditions (unpolluted) or with reference values. Because of the growing social demand for improvement and maintenance of environmental quality in Brazil, some studies have been carried out to establish guideline values for heavy metals in soils. These are pre-set values for the presence of chemicals that enable the verification of possible contamination. The Brazilian National Environmental Agency establishes three guideline values: Reference Value (RV); Prevention Value and Intervention Value. The RV indicates the quality threshold for a considered clean soil to be used in actions to prevent pollution of soil and control of contaminated areas. Soil samples were collected from the states of Mato Grosso and Rondônia, Brazil, at 0-5, 5-10, 10-20 and 20-30 cm layers, in areas of native vegetation (no or minimal human intervention). The objectives of this thesis were: (i) to determine the reference values of heavy metals in soils of Mato Grosso and Rondonia, (ii) to evaluate extraction methods for pseudototais levels of heavy metals (EPA 3051 and aqua regia), (iii) to correlate these values with physical and chemical soils attributes, and (iv) to correlate the results of this study with values established for soils from other Brazilian states. It started from following assumptions: i) no differences will be observed between the natural contents of heavy metals in soils of Mato Grosso and Rondônia by the two extraction methods, ii) the RV of heavy metals for Mato Grosso and Rondônia soils are different from RV obtained for soils from other Brazilian states, and iii) there are significant correlations between natural levels of heavy metals and the physical and chemical attributes of soils. Differences between aqua regia and EPA 3051 were found for Co, Ni, Pb and Zn, the aqua regia method extracting a higher amount of these elements, while the levels of Cr and Cu did not differ between the methods. The aqua regia, in general, had a better recovery of the pseudototal levels of heavy metals in the soils. Contents of Fe and Mn oxides were the variables that, in general, more correlated with the contents of heavy metals in the soils. The organic carbon content did not contribute to assessment of the overall variation of the metal levels because it did not correlate significantly for any variable. Differences between the levels of heavy metals in soils of the world and from other Brazilian states reaffirm the necessity of obtaining reference values for each state or each type of soil, depending on the variation of geomorphological, pedological and geological features of the state.
6

Valores de referência de metais pesados em solos de Mato Grosso e Rondônia / Reference Values for heavy metals in soils from Mato Grosso and Rondônia states, Brazil

Sabrina Novaes dos Santos 10 June 2011 (has links)
Os órgãos de monitoramento ambiental necessitam de indicadores de referência para a avaliação continuada dos impactos ambientais. Indicadores são obtidos por meio da comparação dos teores totais de elementos tóxicos de um solo com valores determinados em condições naturais (não poluídos) ou com valores de referência. No Brasil, com a crescente demanda social pela melhoria e manutenção da qualidade ambiental, alguns estudos foram realizados com o objetivo de estabelecer valores orientadores para metais pesados em solos. Estes são valores préestabelecidos quanto à presença de substâncias químicas que possibilitam a verificação de possível contaminação. A legislação brasileira estabelece três valores orientadores: Valores de Referência de Qualidade (VRQs), de Prevenção (VP) e de Investigação (VI). O VRQ indica o limite de qualidade para um solo considerado limpo a ser utilizado em ações de prevenção da poluição do solo e no controle de áreas contaminadas. Foram coletadas amostras de solo dos estados de Mato Grosso e Rondônia, nas profundidades de 0-5, 5-10, 10-20 e 20-30 cm, em áreas de vegetação nativa (sem ou mínima intervenção antrópica). Objetivou-se com essa dissertação: (i) determinar os valores de referência de metais pesados em solos de Mato Grosso e Rondônia; (ii) avaliar métodos de extração de teores pseudototais de metais pesados (EPA 3051 e Água Régia); (iii) correlacionar estes valores com atributos físicos e químicos dos solos; (iv) correlacionar os resultados desse estudo com valores já estabelecidos para solos de outros estados brasileiros. Partiu-se das hipóteses: i) não ocorrerão diferenças entre os teores naturais de metais pesados nos solos de Mato Grosso e Rondônia pelos dois métodos de extração de teores pseudototais de metais; ii) os VRQ de metais pesados para os solos de Mato Grosso e Rondônia são diferentes dos VRQ obtidos para solos de outros estados brasileiros; e iii) haverá correlação significativa entre os teores naturais de metais pesados e os atributos físicos e químicos dos solos. Houve diferença entre os métodos da água régia e EPA 3051 para recuperação dos metais Co, Ni, Pb e Zn, sendo a água régia o método que mais extraiu esses elementos, enquanto os teores de Cr e de Cu não diferiram entre os métodos. A água régia, em geral, apresentou maiores recuperações dos teores pseudototais de metais pesados nos solos. Os teores dos óxidos de Fe e Mn foram as variáveis que, de forma geral, mais correlacionaram com os metais pesados. O teor de carbono orgânico não contribuiu para avaliação da variação geral dos teores de metais por não correlacionar significativamente com nenhuma variável. As variações encontradas entre os teores de metais pesados dos solos do mundo e de outros estados brasileiros reafirma a necessidade da obtenção de valores de referência para cada estado ou para cada tipo de solo, dependendo da variação das características geomorfológicas, pedológicas e geológicas do estado. / Environmental monitoring institutions need benchmarks for continuous assessment of environmental impacts. Indicators are obtained by comparing the total levels of toxic elements in soils with values determined in natural conditions (unpolluted) or with reference values. Because of the growing social demand for improvement and maintenance of environmental quality in Brazil, some studies have been carried out to establish guideline values for heavy metals in soils. These are pre-set values for the presence of chemicals that enable the verification of possible contamination. The Brazilian National Environmental Agency establishes three guideline values: Reference Value (RV); Prevention Value and Intervention Value. The RV indicates the quality threshold for a considered clean soil to be used in actions to prevent pollution of soil and control of contaminated areas. Soil samples were collected from the states of Mato Grosso and Rondônia, Brazil, at 0-5, 5-10, 10-20 and 20-30 cm layers, in areas of native vegetation (no or minimal human intervention). The objectives of this thesis were: (i) to determine the reference values of heavy metals in soils of Mato Grosso and Rondonia, (ii) to evaluate extraction methods for pseudototais levels of heavy metals (EPA 3051 and aqua regia), (iii) to correlate these values with physical and chemical soils attributes, and (iv) to correlate the results of this study with values established for soils from other Brazilian states. It started from following assumptions: i) no differences will be observed between the natural contents of heavy metals in soils of Mato Grosso and Rondônia by the two extraction methods, ii) the RV of heavy metals for Mato Grosso and Rondônia soils are different from RV obtained for soils from other Brazilian states, and iii) there are significant correlations between natural levels of heavy metals and the physical and chemical attributes of soils. Differences between aqua regia and EPA 3051 were found for Co, Ni, Pb and Zn, the aqua regia method extracting a higher amount of these elements, while the levels of Cr and Cu did not differ between the methods. The aqua regia, in general, had a better recovery of the pseudototal levels of heavy metals in the soils. Contents of Fe and Mn oxides were the variables that, in general, more correlated with the contents of heavy metals in the soils. The organic carbon content did not contribute to assessment of the overall variation of the metal levels because it did not correlate significantly for any variable. Differences between the levels of heavy metals in soils of the world and from other Brazilian states reaffirm the necessity of obtaining reference values for each state or each type of soil, depending on the variation of geomorphological, pedological and geological features of the state.
7

Avaliação da concentração de radônio-222 no ar de postos de trabalho de Curitiba/PR

Del Claro, Flávia 20 February 2013 (has links)
Comissão Nacional de Energia Nuclear (CNEN) / O ser humano está exposto diariamente a várias fontes de radiação natural sendo que a principal delas é o gás nobre 222Rn, pertencente à cadeia radioativa do 238U. A grande importância do estudo do 222Rn se deve ao fato do mesmo ser responsável, juntamente com seus produtos de decaimento, por cerca da metade da dose efetiva proveniente das fontes de radiações ionizantes naturais que é recebida pela população mundial. Além disso, o gás 222Rn ao ser inalado produz isótopos que passam por oito decaimentos radioativos (metade por emissão de partículas alfa e metade por emissão de partículas beta) para chegar ao isótopo estável de chumbo. Essa radiação interage com as células dos tecidos biológicos apresentando alta probabilidade de induzir o desenvolvimento de tumores pulmonares. O objetivo desta dissertação é avaliar os valores de concentração de 222Rn em ambientes de trabalho da região de Curitiba – Paraná, assim como, mensurar os níveis de 222Rn provenientes do solo e de materiais de construção que permeiam os postos de trabalho avaliados. Para o estudo dos níveis de 222Rn indoor foram utilizados detectores de estado sólido CR-39, submetidos à revelação química e leitura manual em microscópio óptico. Os cálculos das concentrações de 222Rn nos postos de trabalho foram obtidos a partir de metodologia de calibração desenvolvida pelo Centro de Desenvolvimento da Tecnologia Nuclear (CDTN) em conjunto com o Laboratório de Radiações Ionizantes da Universidade Tecnológica Federal do Paraná (UTFPR). O detector ativo AlphaGUARD (SaphymoGmbH) foi utilizado para análise das concentrações médias de 222Rn do solo e dos materiais de construção que também foram submetidos ao método de espectrometria gama para avaliação qualitativa e quantitativa dos radionuclídeos presentes nas amostras de areia, argamassa, brita azul, brita vermelha, concreto e tijolo vermelho. A metodologia utilizada para as medidas de solo permitiu encontrar as concentrações médias de 222Rn (radônio) e 220Rn (torônio) presentes no solo. Os resultados das concentrações médias de 222Rn obtidos nas medidas indoor dos postos de trabalho encontram-se entre 36 ± 49 Bq/m³ e 164 ± 51 Bq/m³. Valores esses considerados dentro do limite de referência de 200 Bq/m³ estabelecido por agências internacionais como United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) e o International Commission on Radiological Protection (ICRP), mas um pouco acima do limite de 148 Bq/m³ preconizado pela United States Environmental Protection Agency (EPA). Em relação aos materiais de construção, os valores de concentração de 222Rn encontrados estão em uma faixa de 427 ± 310 Bq/m³ a 2053 ± 700 Bq/m³. As concentrações de 222Rn no solo variaram de 31 ± 2 kBq/m³ a 35 ± 4 kBq/m³ e os valores médios encontrados de 220Rn estão em um intervalo de 41 ± 6 kBq/m³ e 25 ± 11 kBq/m³, os quais constatam que as concentrações do gás radônio do solo estão abaixo do critério sueco que determina que valores inferiores a 50 kBq/m³ não caracterizam uma situação de alto risco. / In every day life people are exposed to various types of radiation arising from different artificial and natural sources and among all of them the main role belongs to the isotope of noble gas 222Rn that makes part of the 238U radioactive chain. The isotope 222Rn is responsible for approximately half of the effective annual dose received by the world population. Being inhaled, the radon isotopes have to undergo 8 radioactive decay events (one half by emitting alpha particles and another half by emitting betas) to get to a stable isotope of lead. This radiation interacting with the cells of biological tissue have very high probability to induce the lung cancer. The goal of present research is to evaluate the activity concentration of 222Rn in the air of workplaces at Curitiba – Paraná State. Simultaneously there were performed the measurements of 222Rn emanation from soil and building materials occurred at evaluated workplaces. Indoor measurements of 222Rn activity were performed using Polycarbonate track etched detectors CR-39 that after the exposition in air were submitted to chemical etching and manual reading using the optical microscope.The calculations of the activity concentration of 222Rn in the air of workplaces were completed using the results of calibration performed by the Center of Nuclear Technology Development (CDTN) in cooperation with the Laboratory of Applied Nuclear Physics of the Federal University of Technology - Paraná (UTFPR).The instant radon detector AlphaGUARD (Saphymo GmbH) was used in the measurements of the average concentrations of 222Rn in soil gas and building materials. Building materials were also submitted to gamma spectrometry analysis for qualitative and quantitative evaluation of the radionuclides present in samples of sand, mortar, blue crushed stone, red crushed stone, concrete and red bricks. The method used for the measurements of radon activity in soil gas allowed to find the average concentrations of two isotopes 222Rn and 220Rn. The average concentration of indoor 222Rn obtained in the measurements in air of workplaces vary between 36 ± 49 Bq/m³ and 164 ± 51 Bq/m³. These values are considered within the reference limit of 200 Bq/m³ established by international agencies such as the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and the International Commission on Radiological Protection (ICRP), but slightly above the limit of 148 Bq/m³ established by the United States Environmental Protection Agency (USEPA). The measurements involving building materials presented the concentration values of 222Rn in a range from 427 ± 310 Bq/m³ to 2053 ± 700 Bq/m³. The 222Rn concentrations in soil ranged from 31 ± 2 kBq/m³ to 35 ± 4 kBq/m³ and the average values of 220Rn are found in a range of 41 ± 6 kBq/m³ and 25 ± 11 kBq/m³, thus the concentrations of radon gas soil are below the Swedish criterion of 50 kBq/m³ that represent the minimum value for high-risk situation.
8

Indexy znečištění pro hodnocení půd / Assessment of soils using pollution indices

Satola, Ondřej January 2020 (has links)
Subject of this diploma thesis is analysis of selected heavy metals in soils which are exposed to long-time cause of contaminants from metallurgical industry in localities Třinec and Ostrava. For assessment of the contamination, indexes for evaluation of soils were chosen. Those indexes are focusing mainly on rate of enrichment of the soils by selected heavy metals and resulting ecological and possibly health risk for human organism. Within every location, 26 samples were extracted, while every sample extract location, were selected to map the level of pollution around metallurgical plants in the most complex way. The analysis of the samples was done by techniques F-AAS and AMA 254 and established metals were mercury, lead, copper, chrome, nickel, manganese and zinc.
9

Characterization And Lime Stabilization Studies On Artificially Lead Contaminated Soils

Gaurave, Kumar 07 1900 (has links) (PDF)
Hazardous waste substances are solid, semi-solid or non-aqueous liquids that exhibit characteristics of corrosivity, reactivity, ignitability, toxicity and infectious property. Major available options for management of hazardous waste include direct disposal into landfill or chemical treatment/stabilization of wastes prior to landfill disposal. Hazardous wastes are accepted for direct disposal in engineered landfills if they conform to the chemical concentration limit criterion (determined by water leach test followed by estimation of the concentration of the contaminant) and compressive strength (the material should have compressive strength > 50 kPa) criterion. Lead is classified as extremely toxic metal. Elevated levels of lead in water (surface and ground water) primarily arise from industrial discharges, and aerial deposition. During its residence in surface water bodies, the lead may interact detrimentally with aquatic life or be abstracted into public water supplies. According to National drinking water standards, the permissible limit of lead in drinking water is 0.05 mg/l. Deposition of air-borne lead, disposal of sewage sludge on land and disposal of industrial effluents on lands are major sources of lead contamination of soils. When incorporated in soil, lead is of very low mobility. Lead retained in soils can be slowly leached to the groundwater thereby impacting human health if consumed for potable needs. Alternatively lead deposited in soils can be absorbed by vegetation (crops/trees) and can impact human health on their consumption. Given the negative impacts of lead contamination on human health, the strong affinity of soils to retain deposited lead and the possible release for human consumption, this thesis focuses on characterization and chemical stabilization of artificially lead contaminated soils in the context of their disposal in hazardous waste landfills. The main objectives of the thesis are: characterize artificially lead contaminated soils for water leachability of lead and undrained strength characteristics as per CPCB (Central Pollution Control Board) guidelines in the context of disposal criteria in hazardous waste landfills. Artificially lead contaminated soils in compacted and slurry states are used in the thesis. Red soil (from Bangalore District, Karnataka) and river sand are used in the preparation of compacted and slurry specimens. The red soil and red soil-sand specimens are artificially contaminated in the laboratory by employing aqueous lead salt solutions as remolding fluids. Lead concentrations of 160 to 10000 mg/l are used in this study. The results of characterization studies with artificially lead contaminated soils help identify contaminated soil materials that require chemical stabilization prior to disposal into engineered landfills. Based on the results of characterization studies with artificially lead contaminated soils, lime stabilization coupled with steam curing technique is resorted to immobilize lead in the red soil-sand slurry specimens and mobilize adequate undrained strength to meet the criteria for disposal of lead contaminated soils in hazardous landfills. After this first introductory chapter, a detailed review of literature is performed towards highlighting the need to undertake chemical stabilization of artificially lead contaminated soils in Chapter 2. Chapter 3 presents a detailed experimental program of the study. Chapter 4 presents the physico-chemical and mechanical characterization of the artificially lead contaminated soils. The ability of artificially contaminated soils to release (artificially added) lead during water leaching is explained using lead speciation results performed using the Visual MINTEQ program. Experimental results illustrated that contamination of compacted red soil and red soil + sand specimens with significant lead concentrations (21 to 1300 mg/kg) resulted in major fractions of the added lead being retained in the precipitated state. Results of water leach tests revealed that lead concentrations released in the water leachates are far less than (0.0011 to 0.48 mg/l) limits prescribed by CPCB (2 mg/l) for direct disposal of lead contaminated materials into hazardous waste landfills. Unconfined compressive strengths developed by the lead contaminated red soil and red soil-sand specimens were significantly higher (100-2700 kPa) than the strength requirement (> 50 kPa) for direct disposal of hazardous wastes in engineered landfills. Lead contamination did not affect the unconfined compression strengths of the specimens as matric suction prevalent in the unsaturated compacted soils had an overriding influence on the cementation bond strength created by the lead precipitates. Visual Minteq tool was helpful in predicting the amount of added lead that was converted to insoluble precipitate form. However the amounts of water leachable lead determined experimentally and predicted by Visual Minteq were very different-Visual Minteq predicted much higher amounts of water leachable lead than experimentally determined. Experimental results revealed that the levels of lead released by the red soil-sand slurries in water leach tests were in excess (13 to 36 mg/l) of the permissible lead concentration (2 mg/l) for direct disposal of hazardous waste in landfills. Owing to water contents generally being in excess of their liquid limit water contents (w/wL ratio > 1) the slurry specimens exhibited undrained strengths below 1 kPa. Lime stabilization and steam curing of the contaminated slurry specimens was therefore resorted to control the leachibility of lead and increase undrained strengths to acceptable limits. Chapter 5 deals with lime stabilization of artificially contaminated slurries that do not meet the leachate quality (lead concentration in water < 2 mg/l) or compressive strength (> 50 kPa). Procedures are evolved for lime stabilization of such artificially contaminated soils to meet both the water leachate quality and compressive strength criteria. Lime stabilization together with steam curing of the lead contaminated slurry specimens effectively immobilized the added lead (2500 mg/kg) and imparted adequate compressive strengths to the contaminated red soil-sand slurry specimens. The lime stabilized contaminated specimens released marginal lead concentrations (0.03 to 0.45 mg/l) in the water leach; these values are much lower than permissible limit (2 mg/l) for disposal in hazardous landfills or values exhibited by the unstabilized specimens (13 to 38 mg/l). Lime addition rendered the contaminated specimens strongly alkaline (pH values ranged between 10.68 and 11.66). Combination of the experimental and Visual Minteq results suggested that precipitation of lead as hydrocerrusite in the alkaline environments (pH 10.68 to 11.95) is not the sole factor for marginal release of lead in water leach tests of the 4, 7 and 10 % lime stabilized contaminated specimens. It is possible that fraction of lead ions are entrapped within the cemented soil matrix. Water leach tests performed at range of pH values (pH 2.5 to 9.6) with 7 % lime stabilized specimens suggested that immobilization of lead as hydrocerrusite or as entrapment in the cemented soil mass in the lime stabilized specimens is practically irreversible even on exposure to extreme pH conditions. The lime stabilized contaminated specimens developed unconfined compressive strengths ranging from 100 kPa (4 % lime stabilized 40 % red soil-60 % sand specimen) to 1000 kPa (10 % lime stabilized 100 % red soil specimen). The significant growth of compressive strength upon lime stabilization is attributed to growth of inter-particle cementation bonds by the CAH (calcium aluminate hydrate) and CSH (calcium silicate hydrate) compounds formed by lime-clay reactions, slight reduction in void ratios and growth of strong inter-particle cementation bonds the during steam curing at 800C. The results of this thesis bring out a procedure to immobilize high concentrations of lead and develop adequate compressive strength of lead contaminated slurry specimens by lime stabilization + steam curing technique. The red soil acted as pozzolana in reactions with lime, while, steam curing accelerated the lime-soil reactions. The procedure can be extended to non-organic slurry wastes that are devoid of pozzolanic material (example, lead contaminated smelting sands). In slurry wastes devoid of pozzolana, materials such as fly ash can be added and the reactions between lime and fly ash would immobilize lead + develop adequate compressive strength. Also, similar to the methodology being adaptable for any non-organic slurries, it can also be extended to other toxic metal bearing wastes, example, zinc, cadmium and nickel.

Page generated in 0.1244 seconds