The US Air Purification System would stand many stories tall starting with a cement base for stability. On top of that cement base would be the main metal base housing of the filter system that holds up the upper structure. The base would possibly also have elevator access for workers to easily use for any repair work.
Above the main base would be your long cylinder connector pieces that connect many stories tall for the air to be cleaned at higher levels. At the top of the long cylinder connectors would be your Air Purification System that does all the cleaning. Housed inside would be your jet-like vacuumed powered fan that would pull in all the polluted and unfiltered air through. Behind the fan would be your 2 chambers of carbon filters that would clean the polluted air coming in and leaving nothing but the purified air going out the other end.
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