METHOD AND DEVICE FOR MEASURING FLOW RATE OF SOLID-VAPOR TWO-PHASE FLOW

PURPOSE:To facilitate the calculation processing for a solid mass flow rate by setting the speed of the solid-vapor two-phase flow in a bent part provided to a conduit to a speed at which a solid material settles, measuring the differential pressure between the upstream and downstream sides of the bent part, and finding the differential pressure value. CONSTITUTION:The powdered coal 1a stored in a feed tank 1 is supplied to an ejector 2 through a rotary valve 1b. Then the powdered coal 1a is guided to a distributing device 4 with air which is supplied to the ejector through a supply pipe 3 and supplied to the tuyere, etc., of a blast furnace through respective branch pipes 7. Each branch pipe 7 has a 90 deg. bent part 7a, connecting pipes 8a and 8b are linked with the upstream and downstream ends of the bent part 7a, and a differential pressure gauge 9 is linked with the other end. An arithmetic control part 10 calculates the solid mass flow rate from the differential pressure values of the bent parts 7a and 7b which are measured by the differential pressure gauge 9 and outputs the flow rate to an arithmetic control part 11. Then the control part 11 outputs a control signal required to equalize the solid mass flow rate inputted from the control part 10 provided on every branch pipe 7 to a target value to a control valve 12, which is controlled.