Scrubbers are used to remove pollutants from vapor streams. These scrubbers can either use a liquid medium or a dry medium for this removal. The liquid medium systems can consist of either a venturi scrubber, packed tower scrubber, or a combination of these. For the dry scrubber, the contaminated vapor flows through the solid media, which is often in the form of pellets which have been impregnated with a chemical to remove the contaminant.