Industrial Pressure Spray Dryer — High-Pressure Nozzle Atomization for Large-Particle, High Bulk Density Powder Products

The Pressure Spray Dryer is a continuous spray drying equipment that pressurizes the liquid feed with a high-pressure pump and atomizes it through pressure nozzles, then dries the droplets in contact with hot air. Compared to centrifugal spray dryers, pressure spray dryers are more suitable for producing powder products with larger particle size, higher bulk density and good flowability, and are especially widely used in detergent, dye and ceramic industries.

The filtered liquid feed is pressurized to 2 to 20 MPa by a high-pressure plunger pump (or diaphragm pump) and atomized into a fine conical liquid sheet through pressure nozzles (atomizing nozzles), which then breaks into droplets. The atomized droplets come into contact with filtered and heated hot air in the drying tower (co-current, counter-current, or mixed-flow configurations available), and moisture in the droplets evaporates rapidly, drying into solid particles. Finished particles are collected at the bottom of the drying tower and by a cyclone separator, while exhaust air is dedusted and discharged by an induced draft fan. The atomization principle of the pressure nozzle: high-pressure feed generates rotational motion through a swirl chamber inside the nozzle, forming a conical liquid sheet when ejected from the orifice, which breaks into droplets under air resistance and surface tension.

• The high-pressure pump is typically a plunger or diaphragm pump with stable pressure and adjustable flow, accommodating feeds of different viscosity and solids content;
• The pressure nozzle (atomizing nozzle) is the core component — different orifice diameters and swirl core structures can be selected based on material characteristics and product requirements to adjust atomization angle and droplet size; nozzle materials include stainless steel, hard alloy or sapphire for wear/corrosion resistance and long service life;
• The drying tower is taller (typically taller than centrifugal spray towers) to ensure sufficient residence time for larger droplets; the tower body can be equipped with jacket insulation or heat tracing;
• Multi-nozzle systems (multiple nozzles operating simultaneously) can be configured to increase single-machine output, or nozzles can be arranged at different heights within the tower for staged drying;
• Supports co-current, counter-current and mixed-flow drying modes to accommodate materials with different heat sensitivity and process requirements;
• Collection, cleaning and control systems are similar to centrifugal spray dryers and can be configured as needed.

• Larger product particles (typically 100 to 300 μm, larger than centrifugal spray products), higher bulk density, good flowability and low dust generation — especially suitable for products requiring large particles, instant solubility or low dust;
• Simple nozzle structure, easy maintenance and low replacement cost, suitable for feeds containing abrasive particles;
• Precise control of product particle size and bulk density by adjusting nozzle pressure, orifice diameter and swirl core;
• Suitable for large-scale continuous production with high single-machine throughput;
• Lower power consumption compared to centrifugal spray (no high-speed motor for atomizer);
• Capable of producing hollow or porous particle products to improve solubility.

Widely used in chemical (detergents, washing powder, dyes, pigments, pesticides, fertilizers, catalysts, resins, organic intermediates), food (granulated milk powder, instant coffee, instant beverages, seasonings, maltodextrin), pharmaceutical (API granules, herbal spray-dried granules), ceramic (ceramic powder, metal oxides, refractory materials) and other (urea, formaldehyde resin, water treatment chemicals) industries.