A treatment apparatus for a mixing device having a concentric barrel configuration. The treatment apparatus includes a manifold including an input end and an output end. The treatment apparatus also includes a conduit body having a manifold end and a nozzle end. The manifold end is connected to the output end of the manifold, and the conduit body includes at least one nozzle at the nozzle end of the conduit body opposite the manifold. At least one fluid pathway is formed between the input end of the manifold, the conduit body, and the at least one nozzle.