Heat exchanger to recover heat from exhaust gases - involves injecting fuel and passing mixture over catalytic surface to at least partially oxidise fuel

摘要

Energy is recovered from a flowing gas stream by injecting a fuel continuously into it to give a stoichiometric proportion of fuel to available O2. The resulting mixture is then fed into a heat exchanger. This exchanger has elements formed from plates welded or otherwise fixed to its surface. The surfaces of these plates are covered with a catalytic metal pref. Pt, Rh, Ru, Pd and/or Ir (alloy) laid on a substrate of refractory inorganic material such as alumina. A catalytic oxidn. of at least part of the fuel occurs and the heat released is removed by the exchanger. A gaseous or liquid fuel can be used. The catalyst can also contain a second metal such as Ti, Va, Cr, Mn, Fe, Co, Ni, Cu, Zu or rare earth metal. The system has the additional advantage that polluting impurities can be removed by the process.