Investigation of Urea Release from a Coated Sphere into a Quiescent Liquid
| Autor: | O. Trass, Huu Doan, M. E. Fayed |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
education.field_of_study
Natural convection Chemistry General Chemical Engineering Population Analytical chemistry Mineralogy Fraction (chemistry) General Chemistry Sherwood number Industrial and Manufacturing Engineering symbols.namesake chemistry.chemical_compound Mass transfer symbols Urea Particle Rayleigh scattering education |
| Zdroj: | Industrial & Engineering Chemistry Research. 38:1125-1132 |
| ISSN: | 1520-5045 0888-5885 |
| DOI: | 10.1021/ie980459q |
| Popis: | Urea (a fertilizer) release from a single opening on a coated sphere into a quiescent liquid was determined by measuring the changes of the weight of the particle with time. Mass-transfer coefficients at different angular positions of the opening were measured under varied Rayleigh numbers from 4.2 × 107 to 5.2 × 1010. A correlation for urea release with the angular orientation of the opening was obtained. Urea release from a population of coated particles was simulated using experimental data for individual particles. A model for the time-varying fraction of urea released was subsequently obtained. It correlates well with experimental data. Overall mass-transfer coefficients for a population of urea particles at various Rayleigh numbers were also estimated using the average Sherwood numbers obtained from local values for various opening orientations. This model could be applicable to the description of urea release from sulfur-coated urea into a quiescent water. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|