Date of Award
2006
Degree Type
Thesis
Degree Name
Master of Engineering Science
Program
Chemical and Biochemical Engineering
Supervisor
Dr. Cedric Briens
Abstract
Pneumatic transport is a widely applied industrial process used for dry bulk material conveying. Due to its importance, the process has been extensively reviewed over the years; nevertheless, attrition and electrostatics problems remain, proving the need for continuous improvement of this industrial process. Therefore, a pneumatic transport pilot plant was extensively used to perform experiments in the areas of saltation, attrition and electrostatics. As well, the attrition results from the pilot plant were compared with attrition in a spouted bed. Detailed literature reviews of these subjects were also given prior to each experimental section. During the saltation experiments, the system limitations were examined. A phase diagram was experimentally configured for polypropylene using the pneumatic transport facility. It was found that design is crucial for proper operation of a transport system and that relying too heavily on literature correlations can lead to problems such as blockage. For the attrition experiments, two grades of PMMA particles were attrited in the transport pilot plant and the experimental attrition rates were determined. The same particles were then used in a sonic jet attrition nozzle spouted bed. A fluidized bed correlation was adapted to the spouted bed and a model was used to compare attrition of the two processes. It was found that the two grades of PMMA particles attrited by two different mechanisms and that the particles in the pneumatic transport system produced more fragments than in the spouted bed system. For the electrostatics experiments a study to reduce the triboelectric effects of a powder was done using different and new antistatic additives. In addition, a bench scale method was developed for testing the effects of additive on the electrostatic charging of powders. The results were encouraging in terms of the potential of the new additive, and, the mixer was proven useful for preliminary predictions of both the electrostatic charging of the powder and the reduction in charge that can be achieved with a specific additive.
Recommended Citation
Al-Senawi, Suma, "ELECTROSTATICS AND ATTRITION IN PNEUMATIC TRANSPORT AND ATTRITION IN SPOUTED BEDS" (2006). Digitized Theses. 5057.
https://ir.lib.uwo.ca/digitizedtheses/5057
