Design And Experimental Research Of Continuous Dense Phase Pneumatic Conveying System

Pneumatic conveying is defined as a method of using compressed gas in a sealed pipeline to convey bulk materials. The system mainly consists of gas source device, feeding device, conveying device, material-gas separation device and control device. Because of its simple structure, flexible layout and easy to realize automation, the system is widely used in rubber, medicine, metallurgy, ports, chemical and electric power industries. Based on the comprehensive research of pneumatic conveying technology and the latest development trends at home and abroad, designed a continuous dense phase pneumatic conveying system. The system through automatic control to achieve the continuous supply of materials and dense phase conveying, improved conveying capacity of the system, achieved the purpose of reducing the energy consumption and avoiding environmental pollution.Firstly, this article discussed the advantages and disadvantages of the existing pneumatic conveying system, analyzed the research background as well as the latest research of the system and put forward the significance and contents of the research.Secondly, based on the theoretical analysis and research of the pneumatic conveying technology, this article classified the pneumatic conveying forms according to different conveying methods, analyzed the particle size and size distribution, accumulation characteristics, conveying characteristics and friction characteristics, and obtained the effect of particle properties on the pneumatic conveying process. This article analyzed the theory of ideal and actual fluidization conveying process by using fluidization conveying principle, and deeply discussed the process parameters of pneumatic conveying system, such as gas velocity, material gas ratio, conveying gas volume, pipeline parameters and gas-solid flow pressure loss.This article designed a continuous dense phase pneumatic conveying system, determined the overall process of the system, designed the gas supply device and gas control device in energy saving, and then designed the rotary feeder and the acceleration chamber, so that it can continuously feed to the system. This article optimized the pneumatic conveying pipeline by using the UHMWPE pipe, designed the gas supply way of auxiliary pipe in energy saving. The optimally designed material-gas separation device consists of the pleated bag filter and the hopper.This article obtained relatively ideal experimental results by using carbon black as experimental material to detect operation conditions of the designed pneumatic conveying system, and analyzed the effect of process parameters such as conveying pressure, conveying velocity and material gas ratio on the conveying pipe pressure loss according to the experimental results.This article set up the gas-solid flow mathematical models of horizontal conveying pipe, vertical conveying pipe and conveying elbow by using the Fluent numerical simulation software, obtained the concentration distribution of materials in the axial conveying pipeline, concentration and velocity distribution of materials in the radial conveying pipeline, concentration and velocity of materials changes with time at the specific point by the simulation. And the results of simulation and experiment are basically identical.Finally, this article summarized the research work and put forward the prospect of continuous dense phase pneumatic conveying system using in the future.