Mass-flow measuring appts. utilising impingement plate, for powder or granules - comprises pressure vessel, gas supply connection, pneumatic bearing and gauge for determn. of differential inner and outer vessel pressure, for low viscosities

摘要

Appts. comprises (a) a pressure vessel, (b) a gas supply connection (7) into the pressure vessel, (c) an air-bearing (2,3) between the impingement of late (1) and the pressure vessel, and (d) a pressure gauge (16) for determn. of the differential pressure between the inside and outside of the pressure vessel. Catalyst flow into a recirculating fluid bed reactor at 650 deg.C, is pref. monitored for max. flow of 4 te/h, using an 80 mm dia. tube (17) feeding downwards onto a 100 mm dia., 90 deg. apex, conical impingement shield (1). A 20 mm ball seal (2) is attached to the shield, and sits in a 20 mm dia., 90 deg. coned seat (3) with a central 10 mm bore. The ball/shield assembly (2,1) is raised slightly from its seat (3) by a constant flow rate airstream controlled from an orifice (14), at 2 m3/h. The resultant reaction of the solids falling on the shield assembly (1) is balanced by the air pressure inside the pressure chamber (6). The gauge (16) measures the difference (deltap) between pressure (Pi) inside the chamber (6) and the external pressure (Po), to provide a measurement w.r.t. the mass flow of the impinging solids. USE/ADVANTAGE - Used in low viscosity media, e.g. gases, at up to 1000 deg.C.