Carbon Dioxide Recovery at Yara

Planning / Implementation / Main components

Axima Refrigeration France

Refrigerant

Ammonia (NH₃)

System start-up

2001

Dry ice made from carbon dioxide is used to frost and store foodstuff. In its production, it is impossible to prevent some carbon dioxide from being released. The gas producer and dry ice manufacturer Yara - previously named Hydrogas - commissioned Axima Refrigeration France to build a refrigeration plant for the recovery and liquefaction of this released carbon dioxide.

Demands

In dry ice production, carbon dioxide is released in a ratio of one kilogram of carbon dioxide per one kilogram of dry ice. Because it is inefficient to allow the gas being released to the atmosphere, Yara was looking for a recovery plant.

Solution

The core element of the ammonia-based refrigeration plant is a flooded heat exchanger that liquefies gaseous carbon dioxide at 18 bars by Ammonia evaporating at -32 degrees Celsius in the same heat exchanger. On this plant, two tons per hour of carbon dioxide are recovered.

Type of facility (circuit)

Condensing unit

Refrigerant

NH₃

Refrigerating volume

600 kg

Refrigerating refrigerant

CO₂

Refrigerating capacity

200 kW

Main components

flooded heat exchanger, screw compressors, tube bundle vaporizer unit

Special features / Comments

The recovery plant's concept sets environmental standards in two ways: On one hand, the excess carbon dioxide is recovered, and on the other hand, the environmentally friendly refrigerant ammonia is used to do so.