A Method for Evaluating Solid Phase Mass Flow in Dense Phase Pneumatic Conveying Systems

Abstract

The invention discloses a method for assessing solid mass flow of a dense-phase pneumatic conveying system. The method includes the following steps that firstly, structural parameters and parameters of a conveying medium of a Venturi tube installed on a dense-phase pneumatic conveying pipeline are obtained; secondly, a pure gaseous phase and gas-solid two-phase calibration experiment is conducted on the dense-phase pneumatic conveying pipeline to obtain a fitting coefficient; thirdly, according to the obtained structural parameters, the parameters of the conveying medium of a Venturi tube and the fitting coefficient of the Venturi tube, solid mass flow Ms of the dense-phase pneumatic conveying system is calculated through the iteration method. The method breaks through the limitation that an existing Venturi flow meter is only suitable for a dilute-phase gas-solid conveying system, the carrier gas density and solid-gas ratio influences are corrected by introducing a two-phase flow factor, and the method is applied to the dense-phase pneumatic conveying field; besides, the solid mass flow is assessed through the iterative trial and error logical algorithm, and the assessment deviation of the solid-phase mass flow in the dense-phase pneumatic conveying is within + / -10%.

Description

technical field [0001] The invention relates to the field of gas-solid two-phase flow, in particular to a method for evaluating solid-phase mass flow in a dense-phase pneumatic conveying system. Background technique [0002] Dense-phase pneumatic conveying of pulverized coal is one of the core technologies in the process of pressurized gasification of pulverized coal in entrained bed. In the pressurized gasification process of entrained pulverized coal, the stability of the feed to the gasifier is directly related to the gasification process index and the stable operation of the gasifier. In the process of feeding materials to the gasifier, if the mass flow rate of pulverized coal added fluctuates, important operating parameters such as the oxygen-carbon ratio will become unstable, causing the temperature in the gasifier to be too high or low, which will affect the normal reaction Carrying out and stable operation of the gasifier: or the reactor lining and nozzles are damag...

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Problems solved by technology

[0006] The technical problem solved by the present invention is to overcome the complicated operation of the existing capacitance method to evaluate the solid mass flow rate, the high price of the instrument, the influence of the calibration result by the properties of the pulverized coal transported, and the unsuitability of the existing differential pressure method to evaluate the gas-solid two-phase flow rate. Due to the shortcomings of the dense phase pneumatic conveying system and the inability of the electronic scale weighing method to evaluate the solid mass flow rate in real time, a method for evaluating the solid phase mass flow rate of the dense phase pneumatic conveying system is provided

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