Carbon dioxide dewar filling

When filling liquid carbon dioxide (LCO2) in gas cylinders:
1. In the cryogenic insulated gas cylinder, when the saturated vapor pressure of the liquid drops to 1.0MPa, the carbon dioxide can form a solid state (dry ice). Therefore, when using and filling liquid carbon dioxide, the air pressure must be higher than this pressure. Prevent the formation of solid carbon dioxide (dry ice) in the Dewar and block the pipeline.

2. Filling of carbon dioxide liquid:
① Connect the low-temperature hose to the inlet valve and gas-phase valve of the low-temperature insulated gas cylinder;
② Use gaseous gas to increase the pressure of low-temperature Dewar filled with gaseous carbon dioxide, and the pressure shall not be less than 1.0MPa;
③Use the liquid phase valve to fill the cryogenic dewar with liquid carbon dioxide, and adjust the liquid phase valve of the storage tank and the emptying valve of the cryogenic bottle to maintain the pressure of the filling pipeline. The filling pressure must be kept above 1.0MPa, otherwise it will Form solid carbon dioxide (dry ice);
④ After filling the pressure vessel, first close the valve on the storage tank, then close the inlet and outlet valves, release the pressure of the hose, and remove the hose.
⑤ When filling, using and storing carbon dioxide cryogenic gas cylinders, the pressure in the cylinder must be kept at 1.0MPa; 3. Defrosting of solid carbon dioxide (dry ice)
① Once dry ice is formed in the cylinder, it is very difficult to remove it;
② The only way to solve dry ice is to rely on natural evaporation, which will take at least a few weeks;
③ It is strictly forbidden to knock, bake or heat the low-temperature insulation pressure vessel with external force;