Filtration, in the strictest sense, applies only to the separation of solid particles from a fluid by passage through a porous medium. However, in the gas processing industry, filtration commonly refers to the removal of solids and liquids from a gas stream. The most commonly used pressure filter in the gas processing industry is the cartridge filter. Depending on the application, a number of filter elements are fitted into a filter vessel. Flow is normally from the outside, through the filter element, and out through a common discharge. When the pores of the filter medium become blocked, or as the filter cake is developed, the higher differential pressure across the elements indicates that the filter elements must be cleaned or replaced.
Adsorption filter is a filter using an adsorption process. Adsorbent which commonly are Carbon, Activated Carbon and/or Activated Alumina based, can be in bulk form or be fitted into cartridges for placement in vessels.