1, What is cold room?
Cold room is a building warehouse using refrigeration machine to reach a certain temperature and has insulation to hold the temperature.
2, Cold room classification:
- According to the structure
◇ Civil engineering cold room building
◇ Steel structure cold room
◇ Mixed structure
- According to the cold room usage
◇ Production type cold room used in food, meat, fish factory
◇ Distribution type cold room used for logistics
◇ Retail cold room used for supermarket
◇ Household cold room
- According to the cold room scale
◇ Large cold storage over 10,000 tons
◇ Medium-sized cold storage 1000-10,000 tons
◇ Small cold storage less than 1000 tons
- According to the cold room temperature
◇ High temperature cold room design temperature (-2~8°C)
◇ Medium temperature cold room design temperature (-10~-23°C)
◇ Low temperature cold room design temperature (-23~-30°C)
◇ Ultra-low temperature cold room design temperature (-30~-80°C)
- According to the cold room goods
◇ Seafood and meat cold room
◇ Dairy and ice cream cold room
◇ Fruit and vegetables cold room
◇ Pharmaceutical and chemicals cold room
◇ Flower cold storage
3, Cold room Floor frost heave and protective measures
It is the frost heaving drum of the soil layer under the cold storage floor. The frost heaving phenomenon in the cold room is related to the thickness of the floor insulation layer, the movement of the freezing point isotherm, the migration of water in the soil, the soil quality and the water content. Although the cold room floor is covered with a certain thickness of insulation, it is not completely isolated from heat transfer. Floor frost heaving is also the biggest problem facing the cold room storage ground structure.
Ways to prevent floor frost heave
Overhead floor (direct and reliable, high cost)
Ventilation floor (with certain limitations)
Heating floor (cost saving, high construction requirements)
When the geological conditions of the multi-layer cold storage are poor, it is recommended to use the overhead floor. When better, the other methods can be considered. When the geological conditions of the single-layer cold storage are poor, it is recommended to use heating or ventilation floor. When the temperature is poor, the overhead floor can be considered.
4, Cold room refrigerant choice
◇Ammonia: the oldest in history, the best choice in the field of industrial refrigeration worldwide. Due to the characteristics of the ammonia system, it is generally used for centralized refrigeration, with a special machine room for large-scale refrigeration systems (more than 10,000 tons of cold storage). There is a trend toward miniaturization and modulation, with an emphasis on improving safety and reducing the amount of charging.
◇ Freon: It is widely used in cold storage to disperse refrigeration. It is suitable for small and medium-sized cold storage and large-scale cold storage with limited ammonia. For environmental protection, large-scale cold storage The Freon system should be avoided as much as possible.
◇ CO2: The cold storage application is mainly based on cascade system and loading system. The low-temperature field is more suitable for cascade. The high-temperature field is suitable for loading. The cascade system is more expensive than the traditional ammonia and Freon system.
5, Cold room defrosting ways
Hot-gas defrosting
Water defrosting
Electricity defrosting
6, Cold storage room mold removal ways
Molds generally grow in dark, damp areas and can withstand lower temperatures. Usually in the high temperature cold room, the situation is the most serious. The mold grows in the cold storage, and the spores fly everywhere, which pollutes the goods and products stored in the warehouse.
◇ Mechanical mold removal (manual cleaning and removal of moldy parts)
◇ Physical mold removal (using temperature, humidity, ultraviolet light, high frequency electricity and copper mesh filters)
◇ Chemical mold removal (carbon dioxide, bleaching powder, sodium fluoride, etc.)