Definition - What does Scrubbing mean?
Scrubbing is the process of removing pollutants from industrial exhaust streams and external matter from gas streams with the help of scrubbers. The following are some of the advantages of scrubbing:
- It controls pollutants, dirt particles, and foreign matter in a gas flow stream.
- It protects downstream rotating equipment.
- It helps in recovering natural gas liquids from natural gas.
- It is helpful in controlling gaseous emissions, especially acid gases.
- It can also be used for heat recovery from hot gases by flue-gas condensation.
Petropedia explains Scrubbing
There are two methods for conducting scrubbing process, i.e., wet scrubbing and dry scrubbing.
- Wet Scrubbing - During this process wet scrubbers trap suspended particles by direct contact with a spray of water or other liquid. In effect, a scrubber washes the particulates out of the dirty air stream as they collide and are entrained by the countless tiny droplets in the spray. When such gas is vented into the atmosphere, it appears like billowing white smoke. The sprayed liquid settles in the bottom of the area and is funneled away from the spraying chamber and collected for disposal. Wet scrubbing eliminates some contaminants like mercury which are extremely harmful if exhausted into the atmosphere and is helpful in dissipating heat from the exhaust gases.
- Dry Scrubbing - Dry scrubbing systems are used to remove acid gases (such as SO2 and HCl) primarily from combustion sources. Dry scrubbing systems are often used for the removal of odorous and corrosive gases from wastewater treatment plant operations. The system produces very little waste material as compared to wet scrubbing. As a result, the collection requirements for a dry scrubber system are much less than for a wet one.