The selection of the filler for small air separation units,large air separation units and liquid air separation plants is very important for the accumulator.
The filler should first of all have a large surface area. In order to be able to store more cold in a smaller volume, the filler should also have a sufficient thermal conductivity and heat capacity, i.e. a large specific heat of volume. In addition, the filler of the accumulator should have a certain mechanical strength, i.e. resistant to wear and tear, not easily broken by severe temperature changes, low price and easy to obtain.