The Experimental Research On The Dual-pipe Pneumatic Conveying System

Dual-Pipe pneumatic conveying system has been widely used in transport of fly ash, cement, raw meal. However, so far as earlier publications are concerned, fundamental studies are scarce and the knowledge of mechanism is limited. In this thesis, we do experimental research to know more about this system.According to the conveying characteristics of fly ash, pressure drop depends on the mass flow rate of air and decrease in proportion to the increase of for any mass flow rate of solids . When keep the same, pressure drop increase with the increase of . The experimental values and the calculated values have the same tendency of change, but the values of experiment are smaller than the calculated values. The author believes the difference is caused by the high amount of turbulence at the orifices when transporting particles.Recently developed electrical capacitance tomography (ECT) was applied to this research. It can be used to calculate the solid fraction and identify the real-time change of flow pattern. With the cross-correlation method, a dual-plane ECT system was developed to measure the solid flow velocity and length of plug. Using the ECT measurement system, we can measure the real-time mass flow rate of solids by combining the plug velocity with the solid fraction. It would be a great help to know the fundamental mechanism of pneumatic conveying...