Characteristics And Experimental Study On Pneumatic Conveying Of Exfoliated Graphite

With the increasing frequent of oil transport at sea,the accident of oil spills occur frequently,and the crude oil or refined oil were leaked in abundance,thus,the ocean ecological environment and human life are under threat seriously.The granule expanded graphite is one of the highly efficient adsorption materials,and it is the highest-performance material in oil absorption rate and oil absorption efficiency.In the technology implementation process of oil-filled graphite industrialization,the pneumatic conveying technology of ultra-light particles is the key research and development technology.However,due to the lack of the transport properties of expanded graphite materials,the equipment development is restricted,using efficient pneumatic conveying package,which makes the expanded graphite conveying equipment have some defects,such as low productivity,poor reliability and low transmission quality,which limits the application and efficient delivery.Therefore,it is necessary to carry out the basic technical studies on the pneumatic transmission characteristics of expanded graphite,and to meet the need of graphite production oil-filled.Firstly,the theoretical analysis and calculation are given for the characteristics of expanded graphite and the basic parameters of pneumatic conveying.Based on the empirical formula about pneumatic conveying and the characteristic parameters of expanded graphite,the main parameters,such as material density,pressure loss,conveying speed and flow pattern in the process of pneumatic conveying of expanded graphite,were calculated analytically,and then,the design scheme of low vacuum suction using expanded graphite is given.Based on the above calculation results,in order to study the pneumatic conveying characteristics of expanded graphite,the experiment device of pneumatic conveying was designed.And a new gas-solid separator was designed to meet the requirements of gas-solid separation and low-breaking rate of light bulk expanded graphite.Then,the simulation model was established.The FLUENT was used to simulate the two-phase flow of expanded graphite.The influence of the relevant parameters and the flow pattern was analyzed,so the stable and efficient transport model was determined based on gas-solid two phase flow.Finally,the experiment program was designed,the measuring experiment was completed,and the collected data was analyzed,the accuracy of the simulation was verified.In the paper,based on the analysis of experimental data and two phase flow simulation,some pneumatic conveying characteristics of light bulk expanded graphite were studied.It has important theoretical and technical reference value for the technology of pneumatic conveying and gas-solid separating for the ultra-light bulk materials.