The aim of this paper is the developement of a model for gas distribution in spouted beds, which is based on the Ergun equation for pressure calculation. For that purpose, the streamtubes followed by the gas have been defined. The gas is distributed from the spout into the annulus according to these streamtubes. Given that pressure drop at any level in the bed (in the spout) is calculated from previously developed correlations, the amount of gas that enters each streamtube is that corresponding to this known pressure drop, and is calculated by means of Ergun equation. Although this is a much simpler model than those already published in the literature, it predicts fairly well the experimental values of gas velocity in the spout obtained by a Pitot tube and the values of residence time distribution in the annulus obtained by stimulus-response techniques in a pilot plant unit. A statistical analysis has been carried out to the mean values of residence time obtained using the model and the more influencial variables are shape factor and particle size (both solid properties), which means that particle characteristics have a greater influence than the geometry of the contactor itself.
Lan honek ohantze finkoan zehar jariakinak jasaten duen presio galera kalkulatzeko Ergunen ekuazioan oinarritutako eredua garatzea du helburu. Eredu honetan hodi korrenteen teoria oinarri hartuko da. Honen arabera, jariakina iturritik eraztungunera doa, eta bertan hodietan banatzen da. Hodian sartuta, jariakina ez da irteten hodiaren alboetatik ohantzearen gainazalera heldu arte, eta beraz hodi bakoitzean sartzen den emaria kalkulatzeko iturrian darion jariakinak jasaten duen presio galera eta hodi korrente bakoitzean sartzen denarenaren arteko berdinketatik lortuko da.
Ereduaren planteamendua argitaratutakoak baino askoz errazagoa izan arren, honek ondo aurresaten ditu planta pilotoan egindako entseiluetan neurtutako balioak, eta lortzen diren datuekin iturria zein eraztungunea zeharkatzen duen emariaren proportzioa eta batazbesteko egoitza denbora kalkulatzen dira. Balioztaturiko tresna berri honekin emariaren distribuzioan parametro eraginkorren analisia burutu da, eta horrela esferotasuna eta partikula tamainua (biak solidoaren ezaugarri fisikoak) gas emariaren patroiaren kontrolatzaile nagusiak direla demostratzera heldu da.
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