CA Storage Overview
- Images: Orchard, fruit markets, apples in storage.
- CA Equipment: Cooling, storage CA rooms, Palliflex system.
CO₂ Adsorber
The VA CO₂ Adsorber is designed for removing carbon dioxide at very low oxygen levels (dynamic storage).
Advantages:
- One-tank system: most efficient for CO₂ adsorption and regeneration.
- Energy-efficient: unique sieve and distribution plates make the system up to 30% more efficient.
- Utilizes a low-oxygen buffer.
Capacity:
150 kg to 900 kg CO₂ per 24 hours.
Nitrogen Generation
VPSA N₂ Generator
- For pulldown on multiple CA rooms.
- Provides more overpressure in CA rooms.
- High capacity, low oxygen (dynamic storage).
- Advantages:
- Low pressure system = low maintenance.
- Carbon (CMS) lifespan > 10 years.
- Oil-free blower.
- Output: 1.0%–0.2% O₂ (99.0–99.8% N₂).
- Compact, ultra-silent, low maintenance.
- Compliant with PID regulations.
PSA N₂ Generator
- Air from compressor (7 bar).
- Output N₂ capacity: 17–210 Sm³/h.
- For CA room supply.
Ethylene Removal
C₂H₄ (Ethylene) Decomposer
- Removes ethylene in ppb range.
- Ethylene is burned at 250°C.
- Return air temperature <5°C due to efficient heat exchanger.
- Suitable for kiwi (<10 ppb).
- Types: ES200, ES600, ES1200, ES1800.
Cooling Control
Refrigeration Plant Overview
- Cooling of CA rooms is managed by setpoint temperature (SP1) in relation to product sensors (warmest T1 & coldest T2).
- Cooling actions are related to circulation and water loss.
Example: CA Room 8 (01/01/2019, 00:00–13:19)
- Ammonia system with Danfoss EKC361.
Temperature Sensor Placement
- a) Setpoint sensor (0.5 m below evaporator)
- b) Block sensor (defrost)
- c) Product sensor 1 (coldest box)
- d) Product sensor 2 (warmest box)
- e) Option to install up to 10 product sensors
- f) Safety sensor (standalone)
Note: Incorrect sensor placement can cause too many short actions and poor product temperature control.
Homogenous Air Circulation
Goal:
- Uniform product temperature and humidity within CA room/bin.
- Control moisture loss.
- Sufficient air circulation (m³/h per m³ room).
Automatic Defrosting
Defrost Methods:
- Electrical
- Fan heat
- Warm glycol
- Hot gas
Requirements:
- Temperature sensor in cooler
- My Fruit control system
Goal:
No ice build-up, as it blocks circulation and cooling.
Moisture Loss in Long-Term Storage
How to Minimize Moisture Loss:
- Optimize cooling system.
- Minimize temperature difference between cooler and room.
- Use My Fruit control for cooling installation.
Other Influencing Factors:
- Pre-cooling (wetting bins)
- Packaging
- Humidification
Typical Moisture Loss (liters/ton/month)
| Variety | Moisture Loss |
|---|---|
| Gala | 1.5–2.5 |
| Jonagold | 1.5–2.5 |
| Elstar | 1.5–3.0 |
| Golden | 1.5–2.5 |
| Braeburn | 2.0–2.5 |
| Granny Smith | 1.5–2.5 |
| Fuji | 2.0–2.5 |
| Red Delicious | 1.5–2.5 |
| Honeycrisp | 1.5–2.5 |
| Pink Lady | 1.5–2.5 |
My Fruit Modules
- Scalable
- IoT ready
- My Fruit App
- Dynamic system
- Respiration & RQ monitoring
- High industrial standards
- Cloud backup
- Worldwide monitoring
- Storage, CA equipment & cooling
Sampling Points: 8, 28, 56, 112
- 24/7 data analysis and reporting
- Customer system backup
- Cloud data service
Smart Interactive Storage of Fruit (ACR)
Version: 01-20120
Why Dynamic CA (DCA)?
- To fight scald (DPA has been banned)
- To retain quality after storage
- To save energy
Methods Used in DCA
- Ethanol measurements
- Fluorescence
- Advanced Control of Respiration (ACR) – Respiration Quotient (RQ)
What is ACR? (Advanced Control of Respiration)
- Most accurate dynamic controlled atmosphere system.
- Goal: Maintain optimal storage condition automatically.
- Method: Measure respiration and determine RQ.
RQ: Early Warning for Fermentation
- Respiration & fermentation:
- CO₂ production (respiration)
- CO₂ production (fermentation)
- O₂ uptake
Respiration Quotient (RQ):
- RQ = CO₂ produced / O₂ consumed
ACR Run in My Fruit
- Shut down cooling and CA activity.
- Overpressure: 10 mm WC in the CA room.
- 7 data measurements of CO₂/O₂ for RQ calculation.
- Automatic O₂ level regulation.
Requirements for ACR
- High quality O₂ analyzer, double scale
- Multipoint calibration
- 2 measuring points per room
- ACR software module
Main Advantages of ACR
- Early warnings
- Prevention of scald
- Better quality during shelf life
- Maintains firmness and color
- Energy saving (cooling)
Protocols
- Detailed protocols for CA equipment, cooling, storage CA rooms, and Palliflex system.
Partners
- ARE Ammonia Refrigeration Engineering
- VA Van Amerongen CA Technology