Gas-Solid Two Phase Flow in Internally Circulating Two-Stage Spouted Desulfurization Tower
To study the circulating fluidized bed desulfurization tower flowing fields, a two-stage spouted tower was presented and an experimental installation was established. Experimental studies on flow fields have been carried out by using a particle dynamic analyzer (PDA). Results indicate: The stable annular flow patterns is obtained in the two-staged esulphurized tower. The irregular and uniform flow is advantage to strength mass transfer at the Veturi inlet of tower. The result of stable back flow of particle at the wall makes it possible that atomizing humidified water or slurry can not directly eject the wall of the tower. At the assurance of atomized covering area, the fact ensures that humid scaling will not be produced at the wall. Micro-particle in gas can be arrested stable dynamic particle layer forming from the particular two stages spouted structure combined proper aggregate accelerating agent.
Effect of the Venturi Inlet Configuration on Flow Character in Circulating Fluidized Bed Desulfurization Reactor
The function of the circulating fluidized bed desulfurization reactor was analysed and the venturi distributor, the latest technology utilized in the industry, was adopted. The characteristics of the velocity field in the riser and venturi diffuser of the circulating fluidized bed desulfurization reactor were studied. The distribution of axial velocity along the radial position and the laws along axis of the riser were thoroughly discussed and analyzed with velocity non-uniformity conception. The values between the experiment and the numerical simulation were compared. The results showed that the uniformity of velocity profiles in the bottom of riser was badly affected by side inlet pipe and circulating feed inlet. As a result, the bad flow behavior in the bottom of riser (arose.) What is more, in the venturi diffusion section, the eddy appeared on the side of circulating feed inlet with the region of steady-flow in the riser far away from the inlet of the riser.
Laminar heat or mass transfer in rectangular channels and in cylindrical tubes for fully developed flow: comparison of solutions obtained for various boundary conditions
Abstract A comparison is made of results obtained with various boundary conditions at the wall of the channels. By comparing blood Sherwood numbers for finite wall resistance with those for constant concentration boundary condition only a small variation is found for various points along the blood channel.