An improved venturi scrubber for removing particulate matter from a gas stream. The scrubber includes ports located either at the throat at the venturi or in the divergent section for injecting gas or air into the stream being processed through the scrubber. The ports may be either a series of openings or a continuous annular opening and are connected by ducting either to the convergent section of the scrubber to receive a portion of the incoming gas stream or to a separate source of gas or air.

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