RU2180074C1 - Cyclone-type furnace extension - Google Patents

Abstract

FIELD: arrangements for simultaneous or alternate combustion of liquid and gaseous fuel. SUBSTANCE: furnace extension has air supply duct, combustion chamber, axial-flow injector with peripheral swirl generator, and device for supplying gas to duct interior and to swirl generator; mentioned device is provided with nozzles in the form of subsonic ejectors; combustion chamber has tangential air-supply nozzles whose outlet flow area reduces with increase in distance from injector; gas supply device is built up of pipeline and two gas manifolds; pipeline feeding gas into duct is equipped with gate valve. EFFECT: enhanced reliability and economic efficiency of fuel combustion at all fuel-to-air ratios and loads carried by boiler unit. 3 cl, 2 dwg

Description

 The invention relates to the field of boiler technology, in particular to devices for the simultaneous or alternate combustion of liquid and gaseous fuels.

 Various cyclone pre-furnaces for burning fuel are known. However, the pre-heating design is not known, which allows reliable and economical simultaneous and alternate burning of liquid and gaseous fuels.

 As a prototype, a cyclone pre-furnace was selected containing an air supply box, a combustion chamber and an axial nozzle with a peripheral swirl (AS USSR 1508048, 1989, IPC F 23 С 5/32).

 Known preheater is not intended for burning gaseous fuels.

 The technical task to be solved is ensuring reliable economical combustion of liquid and / or gaseous fuel at any mixture ratios and boiler plant loads.

 The cyclone pre-furnace for carrying out the method comprises an air supply duct, a combustion chamber with tangential air supply nozzles, an axial nozzle with a peripheral swirler and a gas supply device inside the duct and for a swirl containing nozzle nozzles in the form of subsonic ejectors. The output section area of the tangential nozzles decreases with increasing distance from the nozzle. This ensures approximately the same rate of exit of the mixture of air with gas into the combustion chamber.

 The gas supply device can be made in the form of a pipeline and two gas manifolds. The pipeline can be equipped with a valve.

 1 is a schematic cross-sectional view of a pre-furnace, and FIG. 2 is a side view of the pre-furnace. Arrows indicate the supply of air, gas and fuel oil.

 The invention is illustrated by the example of the design of a cyclone reversible (fuel) preheater.

 The pre-furnace contains an air supply duct 1, an encircled cylindrical body of the combustion chamber 2 with an end cap 3, a shell 4 with end caps 5 and 6 with windows 7. The clip cooling shell 8 is also provided with windows 9. An axial air and fuel oil device (according to the certificate for useful model 12215, 1999) contains a spiral wall 10, a coaxial body 2, a twist regulator 11, a cone 12 with windows 13, a cover 14, a peripheral swirler 15, an axial nozzle 16 with an o-ring 17 on the pipe 18 having windows 19. The gas supply device contains t a gas supply pipe 20 passing through the cover 3 and containing an axial branch 21 and a tangential branch 22 representing a gas manifold, the branches being equipped with valves 23 and 24. An axial gas manifold 25 with radial openings 26 and axial nozzles 27 is installed coaxially to the combustion chamber 2 equipped with subsonic ejector nozzles 28. Gas pipelines of tangential gas supply 29 to the shell 4 are also equipped with nozzle nozzles 30.

 During operation, the pre-furnace air is fed into the duct 1 and the casing 4, where it branches and is fed tangentially through the nozzles and axially through the swirl 13. The part of the air flows from the end vortex chamber into the cone 12, forms an annular stream and displaces the axial recirculation flow. Part of the air from the shell 4 flows through the windows 7 into the cooling shell of the pinch 8, cooling it, and is blown under the torch root through the windows 9 between the boiler screen wiring pipes. Fuel oil is fed into the combustion chamber 2 through the nozzle 16, and the gas supply is regulated first using the valve 23, then - 24. It is possible to operate the pre-furnace only on gas or only on fuel oil.

Claims (3)

 1. A cyclone pre-furnace containing an air supply duct, a combustion chamber, an axial nozzle with a peripheral swirler, characterized in that it further comprises a gas supply device inside the duct and for a swirl equipped with nozzle nozzles in the form of subsonic ejectors, while the combustion chamber is equipped with tangential nozzles air supply, the area of the outlet cross section of which decreases with increasing distance from the nozzle.  2. The cyclone pre-furnace according to claim 1, characterized in that the gas supply device is made in the form of a pipeline and two gas collectors.  3. The cyclone pre-furnace according to claim 2, characterized in that the gas supply pipe into the duct is equipped with a valve.

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