• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • Tagged with
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 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

RESÍDUOS POLIMÉRICOS: QUANTIFICAÇÃO, CARACTERIZAÇÃO, LAVAGEM E TRATAMENTO DO EFLUENTE GERADO NO PROCESSO / POLYMERIC WASTE: QUANTIFICATION, CHARACTERIZATION, WASHING AND WASTEWATER TREATMENT GENERATED IN PROCESS

Streit, Angélica Fátima Mantelli 05 April 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / With the industrialization, the demographic growth and the consumption patterns of society there is an increase in the generation of solid waste, among which include polymeric waste. Thereby, the recycling emerges as a viable alternative, but for it to be effective is very important to carry out the cleaning of the waste, as well as the treatment of wastewater generated in the process. Thus, the main objective of this study was performed quantification, characterization and washing of polymer waste and treating the wastewater generated in the process. For the quantification of different polymeric waste was carried out a data collection in the Association of Selectors of Recyclable Materials (ASMAR). Where, also were collected the packages of HDPE, LDPE, PP, which were characterized by their degree of contamination and were subsequently used in the washing process. The washing process was carried out in three phases (pre-wash, washing and rinse), and using different cleaning products. Regarding the treatment of the effluent was adopted a physical-chemical process via the coagulation / flocculation, sedimentation, followed by filtration. The following coagulants were used: chitosan powder, chitosan diluted in acetic acid, tannin SG, tannin SL and aluminum sulfate. The results from the quantitation of different polymeric residues collected by ASRM demonstrated that the most representative resins in 2014 were the LDPE, with 33.87% and 21.74% with HDPE. Regarding the characterization of polymeric waste depending on their level of contaminants was possible to verify that packages of PP and HDPE, even though they come from selective collection still contained a high level of contaminants, unlike LDPE packaging. As the washing process, it was possible to ascertain that the three stages developed, consisting of an efficient sequence for obtaining clean polymeric residues and suitable for recycling. Furthermore, the combination of sulfonic acid with lauryl and sodium hydroxide showed be more efficient to the other conditions tested in the washing step. Regarding the treatment of the wastewater, the results indicated that the use of aluminum sulphate coagulating was the most efficient in the removal of turbidity. Also was noted the importance of completing the process of coagulation / flocculation before the filtration. From the results obtained in the characterization process of the raw and treated wastewater it was possible to verify that the chosen treatment is effective and appropriate, once the values removed for most of the analyzed parameters were higher than 90%, including turbidity, suspended solids, fixed and volatile amounted to nearly 100% removal. Therefore, the washing process applied was efficient for obtaining clean polymeric materials and favorable to recycling and the method employed for treatment of wastewater also played a great role, since it allows the obtention of a treated wastewater with appropriate quality standards, which gives safety and reliability for its reuse in the washing process of polymeric residues. / Com a industrialização, o crescimento demográfico e os padrões de consumo da sociedade há o aumento da geração de resíduos sólidos, entre os quais destacam-se os resíduos poliméricos. Assim, a reciclagem surge como uma alternativa viável, porém para que esta seja efetiva é de suma importância a realização da lavagem desses resíduos, assim como, do tratamento do efluente gerado nesse processo. Diante disso, o principal objetivo deste estudo foi realizar a quantificação, a caracterização e lavagem dos resíduos poliméricos, bem como, tratar o efluente gerado no processo. Para a quantificação dos diferentes resíduos poliméricos foi realizada uma coleta de dados na Associação de Selecionadores de Materiais Recicláveis (ASMAR). Onde, também foram coletadas as embalagens de PEAD, PEBD e PP, que foram caracterizadas quanto ao seu grau de contaminantes e posteriormente foram utilizadas no processo de lavagem. O processo de lavagem foi desenvolvido em três etapas (pré-lavagem, lavagem e enxague), sendo utilizados diferentes produtos de limpeza. Quanto ao tratamento do efluente foi adotado um processo físico-químico, via coagulação/floculação, sedimentação, seguida ainda por filtração. Os seguintes coagulantes foram utilizados: quitosana em pó, quitosana diluída em ácido acético, tanino SG, tanino SL e sulfato de alumínio. Os resultados obtidos a partir da quantificação dos diferentes resíduos poliméricos coletados pela ASMAR demonstraram que as resinas mais representativas no ano de 2014 foram a de PEBD, com 33,87% e a de PEAD com 21,74%. Referente à caracterização dos resíduos poliméricos em função do seu grau de contaminantes foi possível verificar que as embalagens de PP e PEAD, apesar de serem provenientes de coleta seletiva ainda continham um elevado grau de contaminantes, diferentemente das embalagens de PEBD. Quanto ao processo de lavagem, foi possível averiguar que as três etapas desenvolvidas, consistem em uma sequência eficiente para obtenção de resíduos poliméricos limpos e próprios para posterior reciclagem. Além disso, a combinação de ácido sulfônico com lauril e hidróxido de sódio se mostrou mais eficiente que as demais condições testadas na etapa de lavagem. Quanto ao tratamento do efluente, os resultados indicaram que o uso do coagulante a base de sulfato de alumínio foi o mais eficiente na remoção da turbidez. Também se observou a importância da realização do processo de coagulação/floculação anteriormente à filtração. A partir dos resultados obtidos no processo de caracterização dos efluentes bruto e tratado foi possível verificar que o tratamento adotado é eficiente e adequado, uma vez que os valores de remoção para a maior parte dos parâmetros analisados foram superiores a 90%, inclusive a turbidez, os sólidos suspensos, fixos e voláteis chegaram a quase 100% de remoção. Portanto, o processo de lavagem adotado foi eficiente para obtenção de materiais poliméricos limpos e propícios à reciclagem e o método empregue para o tratamento do efluente também desempenhou uma excelente função, visto que possibilitou a obtenção de um efluente tratado com padrões de qualidade adequados, o que lhe confere segurança e confiabilidade para o seu reúso no processo de lavagem dos resíduos poliméricos.
2

Vibro-acoustic products from re-cycled raw materials using a cold extrusion process : a continuous cold extrusion process has been developed to tailor a porous structure from polymeric waste, so that the final material possesses particular vibro-acoustic properties

Khan, Amir January 2008 (has links)
A cold extrusion process has been developed to tailor a porous structure from polymeric waste. The use of an extruder to manufacture acoustic materials from recycled waste is a novel idea and the author is not aware of any similar attempts. The extruder conveys and mixes the particulates with a reacting binder. The end result is the continuous production of bound particulates through which a controlled amount of carbon dioxide gas that is evolved during the reaction is used to give the desired acoustic properties. The cold extrusion process is a low energy consuming process that reprocesses the post manufacturing waste into new vibro-acoustic products that can be used to meet the growing public expectations for a quieter environment. The acoustical properties of the developed products are modelled using Pade approximation and Johnson-Champoux-Allard models. Applications for the developed products are widespread and include acoustic underlay, insulation and panels in buildings, noise barriers for motorways and railway tracks, acoustic insulation in commercial appliances and transport vehicles.
3

Vibro-acoustic products from re-cycled raw materials using a cold extrusion process. A continuous cold extrusion process has been developed to tailor a porous structure from polymeric waste, so that the final material possesses particular vibro-acoustic properties.

Khan, Amir January 2008 (has links)
A cold extrusion process has been developed to tailor a porous structure from polymeric waste. The use of an extruder to manufacture acoustic materials from recycled waste is a novel idea and the author is not aware of any similar attempts. The extruder conveys and mixes the particulates with a reacting binder. The end result is the continuous production of bound particulates through which a controlled amount of carbon dioxide gas that is evolved during the reaction is used to give the desired acoustic properties. The cold extrusion process is a low energy consuming process that reprocesses the post manufacturing waste into new vibro-acoustic products that can be used to meet the growing public expectations for a quieter environment. The acoustical properties of the developed products are modelled using Pade approximation and Johnson-Champoux-Allard models. Applications for the developed products are widespread and include acoustic underlay, insulation and panels in buildings, noise barriers for motorways and railway tracks, acoustic insulation in commercial appliances and transport vehicles.

Page generated in 0.0755 seconds