Liquid only lance injector

A lance injector for an exhaust aftertreatment system comprising a housing with a reductant supply passage 302 coupled to an injector nozzle 316 having a poppet valve 312, and a return passage 304 which allows reductant to be recirculated to a reductant source, when the valve is closed all of the reductant is recirculated, when the valve is open a portion of the reductant is injected, and a portion recirculates. The supply and return passages may be coaxial. The injector may not use air as a reductant transport mechanism. Further, a lance injector with a hydraulically actuated valve, with a mounting system which coupled the actuator to the exhaust conduit without them being in direct contact. Further, a lance injector having a shaft containing a reductant supply line, wherein air is present between the shaft and the supply line to inhibit heat transfer therebetween.