Process and apparatus using plate arrangement for reactant heating and preheating

A process for contacting reactants with a catalyst in a reaction zone while indirectly preheating and heating the reactants by contact with combustion gases formed in a heat producing zone, said process comprising:

• a) passing a reactant stream through a plurality of narrow reaction channels defined by principal spaced apart plates
• b) heating the reactant stream in a first portion of the channels in the absence of catalyst to produce a heated reactant stream;
• c) passing the heated reactant stream to a second portion of the channels and reacting the heated reaction stream by contact with a heterogeneous catalyst;
• d) passing a methane-containing stream to a plurality of narrow heating channels defined by the principal spaced apart plates and combusting the methane-containing stream by contact with a combustion catalyst to indirectly heat the first and second portion of the heat reaction channels.

An apparatus for contacting reactants with a catalyst in a reaction zone while indirectly heating the reactants by contact with combustion gases formed in a heat producing zone, the apparatus comprising:

• a plurality of alternate reaction channels and heating channels defined by a plurality of primary plates to have a reactant inlet at one end of the reaction channels, a reactant outlet at an opposite end of the reaction channels, a heating fluid inlet at one end of the heating channels and a heating fluid outlet at the opposite end of the heating channels;
• means for excluding a solid catalyst from a preheat portion of the reaction channels located downstream of the reactant inlet and retaining a solid catalyst in a catalytic portion of the reaction channels located downstream of the preheat portion;
• and
• wherein the heating channels define a combustion zone and the heating channels retain a combustion promoting catalyst.