The investigation of the structure and operation of a multi-channel cyclone, separating fine solid particles from an aggressive dispersed gas and vapour flow

Abstract

A multi-channel cyclone is a new-generation cleaning device, which purifies a gas flow by removing fine dispersion solid particles of 2 μm and larger in diameter from it. An aggressive dispersed gas flow can be formed under various conditions, for example, in combustion and processing of various products such as drying of chemical compounds, etc., at high temperature and/or high humidity. Multi-channel cyclones of a new generation have a number of advantages over the most widely used equipment for separating the particulate matter from the air flow such as electrostatic and bag filters, which are rather expensive, difficult to maintain and to be used for separating sticky and moist particles from the aggressive gas flow. The paper examines wood and lignin solid particles of different nature and properties present in a gas-vapour flow. Their adhesion and cohesion, depending on the time of the multi-channel cyclone operation aimed at purifying a dusted gas-vapour flow at high gas-vapour temperature and humidity are investigated. The research is aimed at determining the optimal separation efficiency and the aerodynamic parameters of a multi-channel cyclone and their variation by creating an aggressive dispersed gas flow. It assesses the detrimental effect of the deposition of wood and lignin solid particles on its interior surfaces, their cohesion and adhesion and clogging the system. The efficiency of the cyclone's operation is investigated for the flow, moving at medium rates and containing solid particles of various sizes. The highest cyclone's efficiency is determined for its separation of medium- and small-size solid particles. The theoretical study of kinematic and dynamic gas flow viscosity and the calculation of its coefficients as well as the dew point temperature of the flow are performed and the relationships between them are determined. The obtained results are presented and some recommendations for improving the structure of a multi-channel cyclone for separating sticky and moist particles from a humid and hot gas flow are provided.