A heating system having a steam generator or water heater, at least one economizer, at least one condenser and at least one oxidant heater arranged in a manner so as to reduce the temperature and humidity of the exhaust gas (flue gas) stream and recover a major portion of the associated sensible and...http://www.google.com.au/patents/US7066396?utm_source=gb-gplus-sharePatent US7066396 - Method and apparatus for enhanced heat recovery from steam generators and water heaters
