The system parameters influence on the particle circulation in the fountain-fluidized bed with the central pipe

Abstract

Fluid-mechanical investigations of fountain-fluidized bed with the central pipe were conducted on a cylindrical column of 250mm diameter, 45şC conical bottom, 50mm nozzle and built-in central pipe of 250mm diameter with the changeable distance from the column bottom and changeable total length. The bed was made of non-spherical polyethylene particles of 3.2mm equivalent diameter. The analysis was performed for the effect of air flow from the annulus to the jet on the bed bottom, in the zone below the central pipe and it was found that the fountain-fluidized bed with the central pipe were limited in respect to the maximum value of the fluid flow rate in the bed annulus.

U ovom radu su vršena fluidno-mehanička istraživanja fontansko-fluidizovanog sloja sa centralnom cevi, na cilindričnoj koloni prečnika 250 mm, koničnog dna 45o, sa mlaznicom od 50 mm i ugrađenom centralnom cevi prečnika 65 mm promenljivog rastojanja od dna kolone i promenljive ukupne dužine. Sloj je obrazovan od nesferičnih polietilenskih čestica ekvivalentnog prečnika 3,2 mm. Praćen je uticaj fluidno-mehaničkih i geometrijskih parametara sistema na cirkulaciju čestica sloja. Analiziran je efekat prostrujavanja vazduha iz anulusa ka mlazu na dnu sloja u zoni ispod centralne cevi i uočeno je ograničenje fontansko-fluidizovanih slojeva sa centralnom cevi u pogledu maksimalne vrednosti protoka fluida u anulusu sloja.