Why not use a helium head space C02 tank instead of a chiller?

Why not use a helium head space C02 tank instead of a chiller?

The chiller eliminates the need for helium headspace carbon dioxide tanks. The action of pumping heats up the liquid carbon dioxide causing the liquid carbon dioxide to flash in the pumping head to gas. This results in cavitations and low pump efficiency. Cavitation can be eliminated two ways: first, by use of a chiller assembly to cool the pump head and/or carbon dioxide fluid to about –5 degrees Celsius, eliminating the cavitation problem. Or, second, by use of a higher delivery pressure of carbon dioxide (as delivered in a helium headspace tank at 1,500 psi). Higher delivery pressure keeps the carbon dioxide from flashing to gas, causing the cavitation problem. However, helium headspace tanks cost about $145.00/tank. A standard carbon dioxide is on the order of $30/tank. The chiller assembly pays for itself quickly after about 4-6 months of standard operation. Supercritical Fluid Technologies, Inc. holds a Patent on its “Chill Can” assembly.