CGN seed processing and storage facilities
The seed-storage and -processing facility is located in a separate building. The seed-storage facilities of the CGN consist of the following compartments, all 3 m high:
- deep freezer compartments each of 40 m2
- cooler compartment of 30 m2
- dryer compartment of 12m2
- working compartment of 30 m2
The entire seed-storage building is made of prefabricated sandwich panels filled with insulating foam. The walls of the cold storage compartments (freezer and cooler) are 120 mm thick. The doors of these compartments are 80 mm thick, as are the walls and doors of the drying and working compartments.
In the freezer compartments the temperature is -20°C, in the cooler compartment 4°C, in the dryer compartment 15°C and in the working compartment 20°C.
The humidity is only regulated in the dryer compartment, where it is kept at 15% RH.
These storage conditions can be maintained if the external temperatures range between -12°C during the winter and 30°C with 50% RH during the summer. The wind velocity should not exceed 5 m/s during the winter.
The freezer consists of two compressor units with separate vaporizers and air cooled condensers. The capacity of each unit is at least 50% of the required cooling capacity under the specified external conditions. Defrosting of the units is by heated vapour. The condense water ducts are electrically heated to prevent freezing. The two compressor units act as mutual backups, one unit takes over if the other one malfunctions. At maximum capacity both units are activated.
The cooler equipment is constructed in a similar way as the freezer installation, only with lower capacity. Defrosting of the cooling equipment is not necessary
The drying equipment is an absorption type dryer. The capacity is 82 litre of water per 24 hours at a temperature of 20°C and 60% RH.
Electrical heating systems are used in the drying and working compartments.
Warning installation and fire alarm
People working in the freezer compartments are obliged to wear a man down alarm transmitter which, when activated, will send an alarm signal to a central receiver.
All compartments have been equipped with automatic fire extinguishers using Halon 1301 gas. Each compartment has three or four fire sensors. When one sensor is activated, the alarm is sounded, but no Halon 1301 gas is released until two or more sensors are activated.