Views: 0 Author: Site Editor Publish Time: 2026-07-15 Origin: Site
Seafood releases massive water vapor, brine, salt mist, protein sludge during freezing, so evaporators prioritize anti-corrosion, anti-frost blocking, easy washdown, hygiene.
Fin Spacing (Most critical parameter)
Seafood Type | Recommended Fin Pitch | Reason |
|---|---|---|
Raw shrimp, peeled shrimp | 10–12 mm | Balance heat transfer & frost resistance |
Squid, mussel, wet fish fillet | 12–16 mm | Heavy moisture, avoid rapid fin clogging |
Long-run production (>8h continuous) | Variable pitch 16–10 mm (inlet wide, outlet narrow) | Extend running time between defrosts |
Cooked seafood (low moisture) | 8–10 mm | Higher heat exchange efficiency |
Coil Tube & Fin Materials (Salt corrosion resistance first)
Top choice for seafood processing (shrimp line standard)
- Tube: SS316L stainless steel (resist brine, chloride salt pitting)
- Fins: SS316 stainless steel
Full stainless coil, electro-polished surface for easy chemical washing.
Cost-balanced alternative
- Tube: SS304 / SS316L
- Fins: 3003 aluminum with full epoxy anti-corrosion coating + hydrophilic coating
Suitable for low-salt seafood, cheaper than full SS coil.
❌ Avoid bare copper tube + bare aluminum fins for shrimp/salt seafood – fast corrosion & leak failure.
Defrost System
1. Hot gas defrost (first choice for seafood IQF)
Fast defrost, less water accumulation, lower energy vs electric defrost; ideal for continuous production lines.
2. Electric defrost: Small batch IQF lines, low production volume
3. Water defrost: Rarely used, excess moisture worsens frosting.
Add drain pan with slope, large drain outlet, anti-clog drain pipe to discharge salt defrost water quickly.
Fan & Airflow Design
- High airflow EC energy-saving fans (variable speed VFD)
- Uniform vertical airflow to fluidize seafood for individual quick freezing
- Fan motor with waterproof IP55/IP67 rating, washdown safe
- Air baffles to prevent short-circuit cold air, ensure all product contacts cold air
Application
1. Fluidized bed IQF (small shrimp, diced seafood): 10–12mm fixed fin, SS316 coil
2. Tunnel IQF (fish fillet, squid strips): Variable pitch 16–10mm coil, hot gas defrost
3. Spiral IQF (large shrimp, whole fish): Full SS coil, heavy-duty drain pan, EC variable fans
