Study on the characteristics of self-developed pulverized coal flow regulation valve for coal gasification process

Abstract

Pulverized coal flow regulation valve is one of the key equipment of pulverized coal gasification process, which plays an essential role in regulating coal flow rate. However, due to complex valve flow channels and gas-solid interactions, there were few reports on the characteristics of this valve. In this paper, experiments of dense-phase pneumatic conveying were carried out with a self-developed pulverized coal flow regulation valve installed in the pipeline. Firstly, the effect of the valve opening on the pressure distribution of the conveying system was analyzed. Then, the flow patterns of gas-solid two-phase flow inside the vertical pipe and inside the horizontal pipe were investigated by the Electrical Capacitance Tomography (ECT) system, respectively. Finally, after analyzing the influence of the regulation valve on the gas-solid flow parameters and based on data regression analysis, the relationship between valve opening and solid velocity and concentration were fitted, and a semi-empirical model was established for pulverized coal flow rate prediction. The model can effectively predict the pulverized coal flow rates under different valve openings with deviations mostly less than± 10%, which is of great significance for flow rate regulation in practical applications.