EXTERNAL MIXING PRESSURIZED TWO-FLUID NOZZLE AND A SPRAY DRYING METHOD

摘要

Disclosed herein is an external mixing pressurized two-fluid nozzle for atomising a liquid by means of liquid pressure and gas, comprising an inner feed liquid pipe (1) extending axially between an upstream end and a downstream end, having a feed liquid conduit (2), a feed liquid inlet (3) positioned at the upstream end and a feed orifice (4) positioned at the downstream end, and a co-axial first gas pipe (5) extending radially outside the inner feed liquid pipe (1) and forming a first gas conduit (6) between the first gas pipe (5) and the inner feed liquid pipe (1), the first gas pipe (5) having a gas outlet slit (7) positioned at the downstream end. Said external mixing two-fluid nozzle provides a swirling motion of the gas, which combined with a pressurized feed liquid enables the production of spray dried powder at industrially applicable capacities with low energy consumption and a small particle size.