Measuring concentration of coal powder in blast furnace pulverized coal injection branch by ECT system

It is important for efficient of burn and safety of blast furnaces equipment to measure concentration of coal powder in Blast furnace pulverized coal injection branch system, which is belong to the measurement of gas/solid two phases flow that is a difficult question in industrial process. There are a lot of methods to measure the concentration of coal powder, but all of them have its questions. The paper introduced an experimental research method for measuring concentration of coal powder based on electrical capacitance tomography (ECT). Fine sand used to substitute coal powder and four types of concentration and two distributions of flow patterns was set in experiments. The reconstruction image was obtained by ECT system, and the average grey level and normalized capacitance was used to represent the concentration of coal powder. The paper introduces detail of experimental system, method and resultants. The experimental resultants showed that the relationship between the concentration and the average of grey level value of reconstruction image or normal measured capacitance are single and nonlinearity. In addition, the resultants also showed that the ECT system is ability to detect the blocking state of the pipe.