RU2200285C2 - Spray drying plant - Google Patents

Abstract

FIELD: metal-working, chemical, pharmaceutical, biological, and food industries. SUBSTANCE: spray drying plant designed for spray drying of solutions and slurries has vertical cylindrical chamber, discharge cone, and rod with spray nozzle/ Novelty is that it is provided with newly introduced annular header disposed in bottom part of chamber, gas inlet pipe, spin drier in top part of chamber, and gas intake in the form of coaxial set of varying-length tubes arranged along center line of drying chamber. EFFECT: reduced specific energy requirement. 3 dwg

Description

 The invention relates to techniques for spray drying solutions and suspensions and can be used in the metallurgical, chemical, pharmaceutical, biological and food industries to obtain powdered granular materials.

 Known direct-flow nozzle chamber with a central swirling supply of a drying agent [1, Fig. 6.4, a; from. 160].

 The disadvantages of this camera are the low specific productivity of the working volume of evaporated moisture and high specific energy consumption. The reason for the disadvantages is the relatively low speed of the atomized particles in the gas stream.

 Closest to the technical nature of the present invention is a drying plant of the company "Niro Atomizer" [2], comprising a vertical cylindrical chamber, a discharge cone, a rod with a nozzle located in the lower part of the chamber, an upper vortex inlet of the drying gas and a pipeline for exhaust gas, located under the nozzle [3, Fig. 17, p. 40].

 The disadvantage of the installation is the low efficiency of the drying process and the large dimensions of the drying chamber.

 The present invention eliminates these disadvantages.

 This is achieved by the fact that in the closed loop installation containing a vertical cylindrical chamber, a discharge cone, a rod with a nozzle located in the lower part of the chamber, an annular collector is also introduced, also located in the lower part of the chamber, a drying gas supply pipe located under the nozzle, an activator in the upper part of the chamber and the gas inlet in the form of a coaxial set of pipes of variable length, separated by vertical partitions, located along the axis of the drying chamber.

The present invention due to the introduction of the annular collector, gas supply pipe, activator and gas intake allows
- increase the drying efficiency of the dispersed material by increasing the relative speed of the drying gas;
- compress the spray torch due to the interaction of the ascending and recirculating flows of the drying gas;
- reduce the diameter of the chamber due to compression of the spray torch;
- reduce the sticking of wet products to the walls of the chamber.

 The dimensions of the spray jet are adjusted by changing the speed of the activator.

 Thus, the inventive spray drying apparatus differs from the known new properties, causing a positive effect.

 Figure 1 presents a diagram of the proposed spray drying installation; figure 2 is a section of the gas intake; figure 3 is a section along the axis of the pipe of the annular collector.

 The spray dryer contains a vertical cylindrical drying chamber 1, a discharge cone 2, a rod 3 with a nozzle 4, an annular collector 5, a gas pipe 6 located under the nozzle, an activator 7 and a gas intake 8.

 Spray drying installation operates as follows.

 The source material is sprayed by the nozzle 4 and in the form of a hollow cone moves in the chamber 1 along an ascending-descending path. The drying gas under the action of the activator 7 passes through the intake device 8, rises up the chamber and is released down along the walls of the chamber. Due to the pressure difference created by the activator, most of the drying gas is recycled, crossing the spray jet, while the wettest gas is forced out by the action of centrifugal forces to the walls of the chamber 1 and is discharged by the collector 5. The atomized source material is dried and dropped into the cone 2 in the form of hollow spherical granules unloading.

 Thus, due to the introduction of an annular collector, a gas supply pipe, an activator, and a gas intake device, the spray dryer allows increasing the heat pressure between the drying gas and the dispersed product, compressing the spray torch, reducing the specific energy consumption for moisture evaporation, reducing the diameter of the chamber, and reducing the sticking of wet products to the walls and the bottom of the camera.

Literature
1. Baklastov A.M., Gorbenko V.A., Udyma P.G. Design, installation and operation of heat and mass transfer plants: Textbook. manual for universities / Ed. A.M. Baklastova. - M.: Energoizdat, 1981. - 336 p.

 2. Belopolsky M.S. Drying ceramic suspensions in spray dryers. - M.: Stroyizdat, 1972. - 124 p.

 3. Installations for drying and granulation of mixtures by spraying: Report on research (intermediate) / All-Union. scientific researcher and project. Institute of refractory metals and hard alloys. - GR 72065204; inv. B 553210. - M., 1974,158 p.

Claims (1)

 A spray dryer containing a vertical cylindrical chamber, a discharge cone, a rod with a nozzle located in the lower part of the chamber, characterized in that an annular collector located in the lower part of the chamber, a gas supply pipe, an activator in the upper part of the chamber and a gas inlet in the form of a coaxial a set of pipes of variable length, located along the axis of the drying chamber.

Images