Effect of dispersing bubbles into liquid fluidized beds on heat transfer and hold-up at constant bed expansion

✍ Scribed by S. Viswanathan; A.S. Kakar; P.S. Murti

• Publisher: Elsevier Science
• Year: 1965
• Tongue: English
• Weight: 647 KB
• Volume: 20
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(65)80087-2

✦ Synopsis

Results on heat transfer coefficients and gas-holdup were reported when small quantities of air were dispersed in a liquid (water) fluidized bed of quartz particles (928 and 649 TV mean dia.), the weight of which was varied from 250 to 1250 g. In the case of holdup studies, glass beads of 4 mm were also employed. The experiments were investigated in a 2 in. std. iron pipe and the bed expansion in each case was maintained the same. The bed side heat transfer coefficie.nti were found to increase, attain a maximum and then fall off with the ratio of air to liquid flow rates. Also, for a given size of the particles, the values of the coefficients are found to be dependent upon the weight employed, indicating a critical weight of the latter to achieve higher coefficients. An extension of BANFZOFF'S analysis [ll] to the holdup in three phase fluidized beds was made and it was found that plots of RL + RG/RG vs. L'/G' resulted, in many cases, in straight lines. The effect of solid particles on the gas holdup was noticed after a comparison with holdup data of air-water system.