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You searched for +publisher:"Universidade Estadual de Campinas" +contributor:("Menegalli, Florencia Cecilai"). One record found.

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Universidade Estadual de Campinas

1. Ayub, Gamel Said Eduardo. Desenvolvimento de processo de recobrimento de ureia com enxofre utilizando leito de jorro bidimensional.

Degree: 1997, Universidade Estadual de Campinas

Abstract: The main objective of this work was the development of an experimental apparatus for coating of urea with sulphur. The experimental results allowed to quantify the relation between the quality of the product obtained and the process variables: spout air temperature, sulphur mass flowrate and mass flowrate of atomization air. The quality of the coated urea was evaluated by the dissolution rate of urea through the sulphur, D25%, and by electronic microscopy. The growth of the partic1e and process efficiency were also evaluated. The particles of urea utilized have a quasi-spherical shape. The two dimensional spouted bed was proper1y designed to provi de an adequate solids circulation, with a slanted base angle of 60°. It was built in plexyglass so the flow inside the bed could be observed. The following process conditions were specified for the experiments: inlet air temperature maintained at 69.0°C and 82.5°C, liquid sulphur mass flowrates of 26.8g1min and 33.9g1min and atomization air mass flowrates of 1.0m3 Ih and 1. 4m3 Ih. A double-fluid atomizer was installed in the bottom of the bed and the liquid sulphur was sprayed co-current1y with the air inlet. A factorial planning was the guide for the number of experiments needed. The results showed that the liquid sulphur mass flowrate significatively influences the growth ofthe urea partic1es and the variables that influences the coating quality, in terms of the dissolution rate are the inlet air temperature and the flowrate of atomizing air. The values obtained for the coating efficiency were satisfactory, in the range of 80.34% - 88.93%. The microscopic analysis showed that the inert particles of urea presented holes in their surface and these holes were not totally filled after the coating process. This defect on the surface provided the high urea dissolution rates obtained. It was observed that for the higher leveI of inlet air temperature used, the surface of the coated partic1e showed less defects, and the holes were partially or totally covered leading to a lower urea dissolution rate or better product quality. The sulphur crystals formed during the coating process were smaller, not regular for the lower air inlet temperature, while for the higher temperature of the inlet air the crystals are larger and better grouped together leading to a regular coated surface Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Rocha, Sandra Cristina dos Santos, 1957- (advisor), Universidade Estadual de Campinas. Faculdade de Engenharia Química (institution), Programa de Pós-Graduação em Engenharia Química (nameofprogram), Zanin, Gisella Maria (committee member), Pereira, Nehemias Curvelo (committee member), Menegalli, Florencia Cecilai (committee member), Silva, Meuris Gurgel Carlos da (committee member).

Subjects/Keywords: Revestimentos; Fertilizantes nitrogenados; Processos de fabricação; Ureia como fertilizante; Enxofre; Processo de leito de jorro

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APA (6th Edition):

Ayub, G. S. E. (1997). Desenvolvimento de processo de recobrimento de ureia com enxofre utilizando leito de jorro bidimensional. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/267522

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Ayub, Gamel Said Eduardo. “Desenvolvimento de processo de recobrimento de ureia com enxofre utilizando leito de jorro bidimensional.” 1997. Thesis, Universidade Estadual de Campinas. Accessed December 04, 2020. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267522.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Ayub, Gamel Said Eduardo. “Desenvolvimento de processo de recobrimento de ureia com enxofre utilizando leito de jorro bidimensional.” 1997. Web. 04 Dec 2020.

Vancouver:

Ayub GSE. Desenvolvimento de processo de recobrimento de ureia com enxofre utilizando leito de jorro bidimensional. [Internet] [Thesis]. Universidade Estadual de Campinas; 1997. [cited 2020 Dec 04]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/267522.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ayub GSE. Desenvolvimento de processo de recobrimento de ureia com enxofre utilizando leito de jorro bidimensional. [Thesis]. Universidade Estadual de Campinas; 1997. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/267522

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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