Vegetable Tray Dryer (Hot Air Cabinet) is the most common machine for dehydrating vegetables like onions, garlic, ginger, and leafy greens. For industrial scales ranging from 24 to 220 trays, the machines are classified by the number of trays and the heating method (Electric, Steam, or Gas).

1. Key Technical Details (Range: 24 to 192/220 Trays)

2. Design Variations

• GMP Model (Food/Pharma Grade): Entirely made of Stainless Steel (SS 304 or 316) with mirror-polished interiors. No sharp corners to prevent bacterial growth.
• Standard Model: MS (Mild Steel) powder-coated exterior with SS 304 internal contact parts (trays and racks) to save costs.
• Trolley System: Above 48 trays, machines usually come with Removable Trolleys. You load the trays onto the trolley outside and wheel it into the dryer. A 96-tray dryer typically has 2 trolleys, and a 192-tray dryer has 4.

4. Operational Considerations

• Insulation: High-density glass wool or PUF (Polyurethane Foam) insulation (minimum 75mm) is essential to reduce heat loss and electricity bills.
• Airflow: Large dryers (96+ trays) use cross-flow air circulation with multiple blowers to ensure that the top and bottom trays dry at the same rate.
• Power Source: * Electric: Easiest to install but higher running cost.
• Steam: If you have an existing boiler, steam-heated coils are 40% cheaper to operate.
• Heat Pump: The most modern tech; it uses 75% less electricity but the machine cost is 2x higher.