Patent ID: 8052766

Claim:
A system for removing pollutants from a flue gas, the system comprising a selective catalytic reduction (SCR) system comprising: a SCR reactor containing a NO x reducing catalyst; one or more mesh screens located upstream of the SCR reactor wherein the one or more mesh screens substantially prevent fly ash particles in the flue gas from entering the SCR reactor or otherwise impeding the flow of flue gas therethrough; a mechanical rapping system for impacting the one or more mesh screens to dislodge therefrom accumulated fly ash particles, said mechanical rapping system including a plurality of hammers and a rotating shaft, said plurality of hammers including top and bottom rows of hammers mounted offset from one another on top and bottom surfaces of said rotating shaft; and a control unit including a user interface for manually adjusting settings of the mechanical rapping system including adjusting at least of a striking pressure of the plurality of hammers against the one or more screens, an amount of times the plurality of hammers strike the one or more screens during a specific time period, and a continuity of striking of the plurality of hammers against the one or more screens; wherein said top and bottom rows of hammers are positioned on said rotating shaft so as to alternate impacting the one or more mesh screens when said rotating shaft is rotated.