Reactor system including a catalyst bed module and process for the selective catalytic reduction of nitrogen oxides contained in gas streams

A reactor includes a catalyst bed module having a first grouping including a first plurality of foam catalyst blocks and a second grouping adjacent to the first grouping and having a second plurality of foam catalyst blocks A first back face of the first plurality of foam catalyst blocks and a second back face of the second plurality of foam catalyst face each other in a spaced relationship. The reactor also includes a sealing frame disposed between the first and second groupings and that may maintain the spaced relationship and form a sealed volume between the first and second plurality of foam catalyst blocks and a support frame having a support surface and an opening, the opening is positioned between the first grouping and the second grouping and adjacent to the sealed volume, and the sealed volume and the opening provide a passage for gas flow.