Influence of Orifice Position Deviations on Distribution Performance of Gravity-Type Liquid Distributor Analyzed Through Mathematical Pathway

Abstract

The distribution performance of the gravity-type liquid distributor (GTLD) significantly affects column operation efficiency and the consequent product quality. In industrial settings, maldistribution is normally considered to be caused by vertical positional or coplanarity errors stemming from deflections associated with manufacture and installation, or even by excessive weight. The lack of estimation protocols or standards impedes the description of this error, which influences the corresponding outflow rates. Given this situation, the paper proposes a lumped parameter, orifice position deviation (OPD), to facilitate the calculation of the relative discharge rate error (RDRE) based on a formula derivation, which allows the systematic analysis of the influence of a single orifice or weir OPD. The paper introduces a sensitivity factor K as a concise and unified expression in theoretical RDREs for calibrating the influence of OPD on the RDREs of geometrically different orifices and weirs. With respect to the GTLD, a larger K indicates the need for more strict OPD requirements. The paper verifies that the extent of GTLD outflow nonuniformity is associated with diverging tendencies regarding its morphology, especially in the orifice and weir, which can be determined using our proposed procedures.

Keywords

Liquid distributor / Installation / Orifice position deviation / Relative discharge rate error / Sensitivity factor

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