A heat exchanger design is provided for optimal transfer of thermal energy between a primary reactor-out reformate and a primary reactor-in steam and air. In particular, one embodiment of the present invention comprises a prime-surface true counterflow heat exchanger positioned around the primary reactor. It is emphasized that this abstract is provided to comply with the rules requiring an abstract, which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that is will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).