If the carbon dioxide from the fermentation process was not used for carbonation, then priming should be performed. Priming is the addition of a small amount of sugar to the beer when stored. The residual yeast during storage will convert the sugar into carbonation. A filtration column is shown below. It is employed to remove the yeast still suspended in the beer.
High pressures can destroy the filtration column.
High filter pressures can be caused by a cake of filtered yeast on the trays not allowing the beer to pass. This column uses diatomaceous earth to keep the filter pressure low. Diatomaceous earth is an algae that has a hollow structure similar to a skeleton. Before the beer is entered into the column, it is mixed with the earth. As the mixture is filter, the yeast and the earth both are collected.