An exhaust aftertreatment apparatus comprising: a) a reactor portion which is tubular and has a flow axis parallel with its longitudinal axis, wherein the reactor portion is configured to receive an exhaust stream in a first end region; b) a mixer located within the reactor portion and located downstream of the first end region, wherein the mixer includes at least a portion of a mixing tube which extends at an angle transverse to the longitudinal axis of the reactor portion; c) an outer tube located about at least a portion of the mixing tube and projecting from an exterior of the reactor portion; and d) an injector in fluid communication with the outer tube and the mixing tube and distanced from the reactor portion, wherein the injector is configured to spray a reductant toward the outer tube and the mixing tube.