Further studies of the regimes of fluidization

Heat transfer optimization in a fluidized bed biomass gasification reactor

“…The total energy output from the reactor as a function of increasing bed material circulation rate is monitored. Analysis of the results show that the optimum heat transfer in the gasification reactor occurs at bed material to biomass feed ratio of [25][26][27][28][29][30]. A series of simulations were run by increasing the bed material feed temperature from 847 C -967 C. The output of the total energy from the reactor is maximum at the bed material feed temperature of about 900 C. Another series of simulations were run to investigate the effect of steam feed rate on the total energy output from the reactor.…”

“…The CFB related to this project has three different gas feed positons. The gas is fed at the bottom and at two different positions along the height of the reactor as primary and secondary gas [29,30]. The flow regime and fluid dynamics in the bed are different when the gas feed is located at multiple positions.…”

“…The velocity in this state is Uk. The velocities are calculated using Equations 2 and 3 proposed by Horio 29 . Steady pressure fluctuation maintains the steady rate of particle transport which is important for the uniform heat transfer process in the gasification reactor.…”

Effect of elevated pressure on fluidization phenomena. Final report

“…. r e f i n e d l a t e r i n Yerushalmi and Cankurt (1979). A m o r e , r , e c e n t and more g e n e r a l f l u i d i z a t i o n regime diagram was presented by with actual experimental data using fine alumina particles as bed material.…”

The extraction of bitumen from western oil sands. Final report, July 1989--September 1993

“…U, is defined as the superficial gas velocity at which the differential pressure fluctuations begin to decrease from the maximum value marking the onset of a flow transition to a regime generally identified as turbulent fluidization. (204) Bubble coalescence and growth are predominant below U,, while above U, the bubbles (or voids) become unstable and break down frequently. (205) Uk is defined as the superficial velocity at which the differential pressure fluctuations have decayed to a minimum and begin to level out marking the onset of turbulence or refluxing pneumatic transport.…”