What Is The Difference between Blast Freezer Air Coolers And Cold Storage Air Coolers?

What Is The Difference between Blast Freezer Air Coolers And Cold Storage Air Coolers?

Blast freezer air coolers: Their core objective is “rapid cooling and forced freezing.”

The function of a blast freezer is to rapidly lower the temperature of fresh ingredients (such as meat, seafood, fruits, and vegetables) (typically 30 minutes to 4 hours) from ambient or pre-cooled temperatures (e.g., 8°C) to below -18°C (some applications require -30°C/-40°C). This rapidly lowers the core temperature of ingredients past the “maximum ice crystal formation zone” between 0°C and -5°C, minimizing ice crystal damage to cellular structures. This preserves texture, nutrients, and shelf life. Therefore, air coolers require exceptionally strong instantaneous cooling capacity.

Freezer air coolers: The core objective is “constant-temperature preservation with low-energy maintenance.”

Freezer storage functions to preserve pre-frozen ingredients (core temperature ≤ -18°C) for extended periods (weeks to months). It only requires maintaining a stable internal temperature between -18°C and -25°C (standard setting) to prevent thawing and refreezing caused by temperature fluctuations (which forms large ice crystals and degrades quality). Consequently, cooling fans prioritize operational stability, low energy consumption, and temperature uniformity over extreme cooling speed.

Comparison Dimensions

Design Evaporation Temperature

Quick-Freeze Unit Evaporator: Lower, typically -30°C to -45°C (some ultra-low-temperature quick-freezing units reach -50°C) (Lower evaporation temperature creates greater air temperature differential within the unit, accelerating cooling speed)

Freezer Room Air Cooler: Higher, typically -25°C to -30°C (only needs to maintain a -18°C room temperature, avoiding excessively low evaporation temperatures to prevent energy waste)

Refrigeration Capacity Density

Quick-Freezing Room Air Cooler: High (strong refrigeration capacity per unit volume/area)

Example: A 10㎡ quick-freezing room air cooler can achieve over 15kW of refrigeration capacity

Freezer Room Air Cooler: Low (sufficient to meet storage requirements)

Example: A 10㎡ freezer room air cooler typically provides 5-10kW cooling capacity

Air Velocity and Airflow

Quick-Freezing Room Air Cooler: High air velocity (3-5m/s), high airflow (forcibly and rapidly removes heat from ingredients to accelerate freezing)

Freezer Unit Air Blower: Low air velocity (1.5-3 m/s), moderate-to-low airflow (prevents moisture loss from high air speeds while reducing energy consumption)

Required Cooling Speed

Blast Freezer Air Blower: Fast, must ensure “rapid passage of food core temperature through the ice crystal zone”

Example: Seafood blast freezing requires cooling from 0°C to -18°C within 1-2 hours

Freezer Unit Air Cooler: Slow, only needs to gradually reach the set temperature after food is stored (frozen food does not require rapid cooling)

Example: After frozen food is stored, reaching -18°C within 4-8 hours is sufficient

Component Type

Evaporator Coil

Quick-Freezing Unit Air Cooler: - Pipe Diameter: Typically thicker (φ12-16mm) to increase refrigerant flow

- Arrangement: Dense (small tube spacing) to maximize heat exchange area

- Material: Corrosion-resistant materials preferred (e.g., 304 stainless steel for high-humidity quick-freezing environments)    Freezer Unit Air Cooler: - Tube Diameter: Thinner (φ8-12mm), sufficient for storage cooling capacity

- Arrangement: Sparse (wide tube spacing) to reduce air resistance and energy consumption

- Material: Standard low-carbon steel or galvanized pipes (low humidity inside the warehouse, minimal corrosion risk)

Fan Selection

Quick-Freezing Warehouse Evaporator Coil: Utilize high-static-pressure, high-speed axial fans or centrifugal fans

(Ensure high air volume and velocity to overcome air resistance from dense coils)

Freezer Warehouse Evaporator Coil: Low-static-pressure, low-speed axial fans

(Operate at low air velocity to reduce noise, energy consumption, and product moisture loss)

Defrosting System

Quick-Freezing Room Evaporator: Equipped with enhanced defrosting mechanisms (due to high humidity causing heavy frost buildup on coils, impairing heat exchange):

- Mainstream: Electric heating defrost + hot gas defrost combination (rapid defrosting, minimized downtime)

- Auxiliary: Automatic defrost controller (frequent defrosting ensures continuous cooling)

Lower defrosting requirements (low humidity inside the storage, slow frost formation):

Freezer Unit Air Cooler: - Mainstream: Hot gas defrosting or electric heating defrosting (either type is sufficient)

- Auxiliary: Timed defrosting (1-2 times daily is sufficient)

Drip Pan / Drainage

Quick-Freeze Room Evaporator: Large drip pan capacity, thick drain pipe diameter (≥φ32mm)

(High defrost meltwater volume requires rapid drainage to prevent ice buildup)

Freezer Room Evaporator: Small drip pan capacity, thin drain pipe diameter (φ20-25mm)

(Low meltwater volume; standard drainage sufficient)

Quick-Freezing Chamber Air Cooler

Typical Applications: Food processing plant quick-freezing rooms, seafood quick-freezing lines, meat rapid-freezing chambers

Suitable Ingredients: Fresh salmon, shrimp, chilled fresh meat, pre-cooked meals (requiring rapid freezing to lock in freshness)

Freezer Room Air Cooler

Typical Applications: Food warehouses, supermarket freezer sections, cold chain logistics transfer facilities

Suitable Ingredients: Pre-frozen meat, frozen seafood, ice cream, frozen dumplings (long-term storage)