DRY ICE PELLETS are manufactured by taking Liquid CO2 and depressurising it in a chamber or tower of a dry ice pelletizer (taking it from 13-25 bar to 1 bar). This will form 50% dry ice snow and 50% gas. The snow is compressed and extruded through extruding plates. Industrial size is 3 mm for dry ice blasting.
No CO2 gas is produced in the manufacture dry ice pallets. The CO2 used comes either from a natural resource such as underground volcano’s or as a bi-product from fertilizer production or from the process of manufacturing Ethanol.
Mostly, large industrial gas companies produce dry Ice and there are also a few private manufactures of dry ice.
As dry ice is mostly manufactured at centralised facilities and so the cost of shipping can be a significant factor in costs. Distances of more than 300-500 kilometers can have a negative effect on the dry ice resulting in poor quality for blasting. Long transport times or poorly insulated containers can quickly give losses of 10-15 % due to sublimation.
Companies like BOC and AIR LIQUIDE do not necessarily have dry Ice Pellets available from all their outlets. Dry Ice pellets usually require pre –ordering to make sure that the freshest (and hardest) pellets can be delivered. Please check with your supplier to ensure the best product.
The ability to produce high density Dry Ice Pellets in house offers many advantages.
The important factors when considering purchasing a Dry Ice Pelletizer are, besides the obvious fact that you want lowest capital investment cost and also that you a machine with well known reliable components, with the minimum of maintenance cost.
Besides a durable 100% stainless steel cabinet, the DIP120 pelletizer is built using components from Danfoss, Siemens and high performance hydraulics power units as the key components for the operation of the Pelletizer. All component suppliers have world-wide service centres so in the unlikely event of having to replace or service a component these will be available locally.
When manufacturing dry ice the conversion of liquid CO2 to dry ice is about 2.2kg to 2.5kg of liquid CO2 to make 1kg of dry ice pellets.
The special design of the DIP120 for supplying liquid CO2 to the Pelletizer Press Chamber, brings this conversion close to 2.2kg. This of course also requires that the installation of liquid CO2 tank and supply piping from the tank to the pelletizer is done according to our guidelines.
HANDLING, TRANSPORTING AND STORING DRY ICE
Dry ice will be supplied in insulated containers in sizes from typically 200-400 kg. With an average consumption rate of 40-50 kg/hour the typical filling of the hopper of the dry ice blaster of 20-25 kg, then the dry ice box will be opened many times during a day. Any heat from the environment will be transferred to the dry ice box and significant losses can occur if the lid is not closed immediately after filling up the blaster hopper.
When transporting dry ice pellets it is important that the vehicle has a separate loading compartment to the passengers cabin. CO2 can rapidly build up in a vehicle and can lead to accidents.
Store the dry ice boxes in a shaded and ventilated area. Depending on the insulation of the dry ice boxes, then losses due to sublimation can amount to 5-15% per day.