METHOD OF BURNING LIQUID OR GAS FUEL AND AIR HEATER Russian patent published in 2007 - IPC F23C9/06 F23D14/18 F24H3/00 

FIELD: heat power engineering.

SUBSTANCE: method comprises supplying fuel to the burner with simultaneous supplying of the primary air, burning fuel in the mixture with the primary air in the flue pipe of the combustion chamber, supplying the secondary air to the flue pipe downstream, afterburning the unburned fuel in the furnace gases in the afterburning chamber, supplying air to the flow of the hot gases outflowing from the afterburning chamber, and discharging heated air to supply it to the consumer. The burning and afterburning processes are carried out in three stages. In the first stage, the mixture of fuel with the primary air is burnt out for the low excess of the primary air. In the second stage, the burning fuel-air mixture is distributed over the periphery of the flue pipe, is swirled, and mixed with a portion of the secondary air that is supplied to the flue pipe at least in two zones. The mixture with high air excess coefficient is intensively burnt out. In the third stage, the remaining portion of the secondary air is supplied to the flue pipe and, being cooled and enriched with oxygen, the flue gases are supplied to the afterburning chamber and unburned fuel in the flue gases is burnt out in the chamber. The air heater comprises burner (1) with fan of the primary air, combustion chamber with external casing (2) and flue pipe (3) provided with ports (4) and (5) for supplying the secondary air and arranged in outer housing (2) to define ring passage (6) between flue pipe (3) and outer housing (2), and afterburning chamber (7) for unburned fuel in the flue gases. Fan (9) for blowing the secondary air is connected with the space of outer housing (2) of the combustion chamber. Swirler (10) made of a hollow conical mixer is mounted in flue pipe (3) and separates it into the primary A and secondary B chambers. The primary flue chamber A is interposed between burner (1) and swirler (10). The second chamber B is interposed between swirler (10) and afterburning chamber (7). Openings (4) and (5) for supplying secondary air to flue pipe (3) are arranged in at lest two zones of the secondary flue chamber B first of which is closer to swirler (10) , and the second chamber with openings (5) is closer to afterburning chamber (7). Ring passage (6) between flue pipe (3) and outer housing (2) is closed from the side of afterburning chamber (7).

EFFECT: expanded functional capabilities and enhanced completeness of burning.

5 cl, 1 dwg