A carbon dioxide (CO2) scrubber is a device which pulls carbon dioxide out of the air and traps it. While the device does not address the production of CO2 in the first place, it does limit the amount of this greenhouse gas which is released from the atmosphere. Using such scrubbers can potentially have an impact on global warming trends, as the scrubbers can be used to control the release of CO2 to protect the environment.
There are a number of settings in which a CO2 scrubber can be used. In industrial settings, these devices are used to trap CO2 which is emitted as a byproduct of the manufacturing process. Other scrubbers to trap an assortment of chemicals and gases may also be installed to reduce the amount of pollution produced. In some regions, these scrubbers are required by law as part of goals to reduce pollution and to limit the release of greenhouse gases.
CO2 scrubbers are also used on systems such as enclosed breathing devices, climate control systems, and so forth, to pull CO2 out of the air so that it will be safe to breathe. Scrubbers can also be mounted on things such as aquaria to control the mixture of gases in the water for the safety of the organisms which live inside. More generally, researchers have talked about installing scrubbers in the open air to trap CO2 which is produced by things like cars, as fitting scrubbers to individual vehicles is not necessarily practical, but using a CO2 scrubber to clean the air in general might work.
There are a number of ways in which a CO2 scrubber can function. Some scrubbers absorb or adsorb the CO2, others create chemical reactions to break it down. In some systems, such as reactors or absorbers, the CO2 can be sequestered and the reactor or absorber can be reused. This contributes to the efficiency of the CO2 scrubber. In other cases, the reactant material may need to be periodically refilled or replaced so that the CO2 scrubber can continue to work.
Using an air scrubber only addresses part of the problem. One is still left with trapped CO2 which needs to be responsibly disposed of. While there are some industrial and commercial uses for carbon dioxide, these uses do not create enough demand to use up the CO2 trapped by scrubbers. Numerous ideas have been put forth for handling trapped CO2 safely. Researchers have also criticized the scrubber model, arguing that the focus should be on making less CO2, rather than trapping it after the fact. Advocates argue, however, that production is unlikely to go away, so measures which will reduce the amount released have value.