Patent DE-19900655-C1 (DE)
Title: Bulk material transport equipment, especially for bulk material injection in metallurgical plants, has a flow and pressure monitoring system for regulating a deposit, blockage and coarse particle flushing gas system
Inventor: WOLF KURT
IPC: F23G5/44
Filed: 1999-01-11
Granted: 2000-10-12
Abstract: Bulk material transport equipment, comprising a flow and pressure monitoring system for regulating a deposit, blockage and coarse particle flushing gas system, is new.  Equipment for producing a constant bulk material stream of any desired magnitude, for dosed filling of installations and for dosed input into transport pipelines, comprises a pressurized dosing vessel, a weighing system, a discharge cone, a pressure measuring and regulating unit and a transport pipeline adjoining the discharge cone, the bulk material stream being produced by raising the pressure in the dosing vessel. The equipment is designed such that, independently of the particle size and the flow properties of the bulk material, a constant bulk material stream of any desired magnitude is obtained by provision, below the dosing vessel, of a dosing unit comprising an outlet funnel (4), a bulk flow cone (5), a dosing and flushing fitting (6) with a throttle, two pressure measuring locations (8, 9), a differential pressure measuring and regulating unit (10), a coarse fraction collection point (12), a transport line (13), a pipe elbow (14), a transport gas inlet (15), a transport gas regulating valve (17), a transport gas flowmeter (18), a flushing gas valve (19), a gas permeable slide face (20), an aeration gas regulating valve (21), a pressurizing gas valve (22), a pressure relief gas valve (24), a dosing and flushing fitting adjustment drive, a dosing and flushing fitting ball, a flushing gas inlet and a flushing gas outlet. The outlet funnel has an entry cross-section (AE) and cone angle ( alpha ) only sufficiently large to allow free passage of easily flowing or coarse grained bulk material and comprises the gas permeable slide face (20), aeration gas being supplied through the regulating valve (21) only for initiating sliding of cohesive non-freely flowing bulk material. The bulk flow cone (5), following the outlet funnel (4), and the throttle have a \-75 deg  wall slope suitable for all bulk materials and are filled uniformly and reproducibly with non-turbulent bulk material. The bulk flow cone (5) and the dosing and flushing fitting (6), equipped with an exchangeable variable size throttle, have a height (H1 minus H2) of 200-800 mm. One pressure measuring location (8), installed at height H1, allows differential pressure measurement (10) together with the other pressure measuring location (9) after the throttle and, together with the pressurizing gas and pressure relief gas valves (22, 24), allows differential pressure regulation (10) for time-defined ejection of bulk material from the bulk flow cone (5) through the throttle. The dosing and flushing fitting (6) has a flushing gas inlet and a flushing gas outlet which, in the closed position of the fitting adjustment drive, allow deposits, blockages and coarse fractions to be blown out of the ball to the separate coarse fraction collection point (12). The transport line (13) begins with a small radius pipe elbow (14) so that pressure relieved bulk material drops directly into the transport gas which enters through the transport gas inlet (15) and which is regulated by the flowmeter (18) and the regulating valve (17). The transport line (13), together with the installed transport gas flow and pressure measurement locations (18, 9), forms a bulk material flow monitoring system in which blockages or an empty transport pipe are indicated by changes in the transport gas flow and pressure level, so that correct bulk material flow can be maintained by brief closures of the dosing and flushing fitting (6).