Gas adsorption technologies

Adsorption gas treatment can have two main configurations and these differ in how the adsorbent interacts with the contaminant: this interaction can be through an adsorbent bed or the adsorbent can be injected into the gas stream. Depending on the application, the presence of other contaminants or the interaction with other treatment technologies, one configuration or another applies. However, the following describes a configuration that can serve as the basis for several gas adsorption systems:

1. Addition of adsorbent and/or reagent (if applicable): The adsorbent and/or reagent is injected into the contaminated gas stream to improve capture efficiency and capture other pollutants from the gas (e.g. acid gases).
2. Adsorbent Bed: The contaminated gas, either alone or with the reagent, passes through an adsorbent bed. This bed usually consists of porous materials such as activated carbon, zeolites or other specialised adsorbents. On the surface of the adsorbent is where the contaminants adhere and where the adsorption process takes place.
3. Filtration: After passing through the adsorbent bed, the clean gas may have traces of dust or particles. This may involve the use of additional filters to retain solid particles or small residual amounts of contaminants.
4. Desorption or Regeneration (if applicable): After a certain operating time, the adsorbent bed can reach its maximum adsorption capacity. At this point, it is usual to exchange the adsorbent bed for a new one and apply a desorption or regeneration process to the used one to release the adsorbed contaminants.