METHOD AND SYSTEM FOR RECOVERING HEAT FROM FURNACE WASTE GASES AND FURNACE BURNING FOSSIL FUEL Russian patent published in 2014 - IPC F27D17/00 F27D3/00 

FIELD: heating.

SUBSTANCE: invention relates to the method and system for recovering heat from waste gases from a furnace where fossil fuels are burnt. The method involves the delivery of waste gas flow to an air heater, calculation of mass flow rate of acid material passing in the waste gases, of mass flow rate of alkaline particles charged to the waste gas flow for the acid material neutralisation, alkaline particle charging with the distribution of particle sizes at the calculated mass flow rate to the waste gas flow upstream the air heater, calculation of the degree of waste gas macroparticle aggregate, adjustment of at least one of the mass flow rates at which the alkaline particles are charged into waste gases and distribution of sizes of the alkaline particle charged into waste gases so that in case of pressure drop exceeding a prespecified limit, a relatively greater percent of large particles is charged for the purpose of contacting with heat exchange elements and for sticking of greater amount of alkaline particles to them to neutralise acid material condensed on the elements, and in case of pressure drop lower than the prespecified limit, a relatively small percent of large particles is charged. A system for recovering heat from waste gases is also described.

EFFECT: transfer of greater amount of heat from a flue is provided as well as reduction of waste gas temperature in the outlet hole without excessive fouling.

13 cl, 6 dwg