In a coke oven having a first heating wall and a second heating wall, a cross over duct arranged to fluidly connect the first heating wall and the second heating wall. The cross over duct further comprising a passageway in communication with the first heating wall and the second heating wall.

A flue block for a heating wall of a coke oven battery, the flue block having a proximal end and a distal end, the flue block comprising a first aperture disposed within the flue block, and a riser arranged in said first aperture. The flue block may also comprise a second aperture disposed therein, the second aperture spaced apart from the first aperture, and a second riser arranged in the second aperture. The flue block may be configured such that the riser is arranged to extend past the proximal end of the flue block. The flue block may be also configured such that the first riser extends past the proximal end. The flue block may be further configured such that the second riser extends past the proximal end.

A flue block for a heating wall of a coke oven battery, the flue block having a proximal end and a distal end, the flue block comprising a first aperture disposed within the flue block, and a riser arranged in said first aperture. The flue block may also comprise a second aperture disposed therein, the second aperture spaced apart from the first aperture, and a second riser arranged in the second aperture. The flue block may be configured such that the riser is arranged to extend past the proximal end of the flue block. The flue block may be also configured such that the first riser extends past the proximal end. The flue block may be further configured such that the second riser extends past the proximal end.