Patent ID: 7875254

Claim:
An apparatus for contacting two reactants to produce at least one product, said apparatus comprising: a vertically disposed vessel having a vertical axis, a sidewall, an upper portion and a lower portion; a draft tube comprising at least one heat exchange means, said draft tube providing a riser conduit within said draft tube and a downcomer conduit between said draft tube and said sidewall, said draft tube extending into the upper portion of said vessel and comprising at least one opening in said upper portion so as to provide fluid flow communication between the riser conduit and the downcomer conduit and extending into the lower portion of said vessel and comprising at least one opening in said lower portion so as to provide fluid flow communication between the riser conduit and the downcomer conduit; an inlet means for introducing said reactants; and a gas outlet; wherein said draft tube is demountable engaged with said vessel sidewall in said lower portion of said vessel.