الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 178 |  |  |
| | | from | 178 | | |
Abstract
The present study on liquid-solid mass transfer at a rotating packed bed reactor and a stationary packed bed located on a rotating impeller have revealed the following results: A. Rotating packed bed reactor• It was discovered that the mass transfer coefficient rose as bed rotation speed increased. • while increasing ring diameter and bed height were found to decrease the mass transfer coefficient. • A dimensionless mass transfer equation suited for scaling up and reactor design was used to correlate the data. • Measurement of the specific mechanical power consumption (ϵ) of the rotating bed under different conditions has revealed that the energy utilization efficiency represented by the ratio between the volumetric mass transfer coefficient 𝐾𝐴 and the specific power consumption ϵ (𝐾𝐴∈) increases with decreasing bed rotation speed. • The rotating bed reactor may be used to conduct diffusion-controlled liquid-solid reactions, such as biochemical reactions involving imobilised enzymes or cells, photocatalytic reactions, the recovery of heavy metals from wastewater through cementation, and the elimination of organic pollutants through catalytic wet oxidation. B. Stationary packed bed located above a rotating turbine• Using a technique that involves measuring the rate of diffusion-controlled copper dissolution in acidified dichromate, the rate of mass transfer was calculated. • The rate of mass transfer was discovered to decrease with increasing particle diameter and bed height, yet to rise with impeller rotation speed. • A dimensionless correlation was employed to correlate the data, which can be used to scale up and construct the reactor. iii• The energy utilization efficiency of the reactor (𝐾𝐴∈) was found to pass through a maximum value at a certain impeller rotation speed. The presence of baffles was found to have little effect on the performance of the reactor. • It was highlighted that the reactor might be used to conduct diffusion-controlled photocatalytic reactions as well as other heterogeneous catalytic reactions for the creation of fine compounds, medicines, and the removal of organic contaminants from wastewater. • A comparison between the performance of rotating packed bed with that of a stationary packed bed placed above a rotating impeller using the criterion (𝐾𝐴∈)revealed that stationary bed located above a rotating impeller outperform rotating bed. That is to say the energy utilization efficiency of stationary packed bed placed above a rotating impeller is much higher than that of a rotating packed bed.