SPRAY DRIER Russian patent published in 2008 - IPC F26B3/12 

FIELD: heating, drying.

SUBSTANCE: invention relates to the technique of drying particulate materials and may be used in the microbiological, food, chemical and other industries. A spray drier comprises furnace with a mixing chamber, turboblower, waste air filtering circuit and drying chamber, whereto a material is supplied via a spray nozzle. Moreover, a drying agent is blown by a blower from the furnace in co-current with the sprayed material, and fine solid particles of the dried material settle on the bottom of the chamber and then a screw takes them off, while the waste drying agent undergoes a preliminary acoustic treatment in a dust trapping acoustic unit, and the waste dusted drying agent undergoes a preliminary acoustic treatment in an acoustic unit having the following optimal parameters of medium-disperse dust sound treatment: sound pressure level of 140 dB and above, oscillation frequency of 900 Hz, dust content in the flow not less than 2 g/m, insonation time 1.5...2 sec. Next the drying agent is forwarded to a cyclone with a hopper, wherein the major part of entrained dry material is extracted, and final filtering of the agent takes place in a hose filter, an exhaust line of which contains recirculation valve that switches the flow of the treated and filtered air to the inlet of the furnace mixing chamber. Moreover, the circuit includes microprocessor that is connected with pressure, temperature, humidity and flow speed detectors installed in elements of the drying circuit and with actuators that control parameters of all the elements of the drying circuit. Said microprocessor analyses current parameters of the drying process and sets an optimal mode by sending controlling signals to the actuators of the drying circuit elements. The spray nozzle has the form of an acoustic spray nozzle comprising housing that contains barrel and rod with a conical flange that forms an acoustic generator made of a nozzle and a resonator, having the form of at least one spherical cavity, arranged inside the central rod that is coaxially arranged in the barrel being coaxial towards the housing. Moreover, the spherical cavity is connected via a calibrated orifice with an annular slot that is formed by the barrel and rod faces on the tapered flange side, and the rod is capable to fixedly move along the housing axis by means of a threaded joint fixed with locknuts.

EFFECT: improving the drying efficiency.

2 cl, 2 dwgg