METHOD OF STAGED COMBUSTION OF LIQUID FUEL AND OXIDISER IN FURNACE Russian patent published in 2008 - IPC F23C99/00 

FIELD: technological processes.

SUBSTANCE: method of staged combustion of liquid fuel and oxidiser, in which at least one jet of liquid fuel is injected in sprayed form and at least one jet of oxidiser is injected, at that jet of oxidiser consists of first oxidiser jet and second oxidiser jet, first oxidiser jet in injected close to liquid fuel jet to achieve first incomplete combustion, gases that are produced during such first combustion still contain at least portion of fuel, whereas second oxidiser jet is injected at the distance of l₂ from the liquid fuel jet, which is more than the distance between liquid fuel jet and first oxidiser jet, which is closest to liquid fuel jet, in order to combust part of fuel that is present in gases, which are formed during first combustion, first oxidiser jet is divided into at least two first jets - at least into fist counted screened first jet, which is injected coaxially around the jet of liquid fuel in sprayed form, and at least into second counted oxidizing first jet, which is injected at the distance of l₁ from liquid fuel jet. Liquid fuel jet in sprayed form is received by means of coaxial injection of spraying gas jet around liquid fuel jet. Spraying gas is selected from gas-oxidiser, such as air or oxygen, or inertial gas, such as nitrogen, or water steam. Weight speed of spraying gas jet makes from 5 to 40% of weight speed of liquid fuel jet. Distance l₂ between jet of second oxidiser and fuel jet makes from 8D₂ to 40D₂, where D₂ presents diameter of circle with the same area as area of injector, through which the second oxidiser is injected. Distance l₁ between second counted jet of first oxidiser and liquid fuel jet makes from 1,5 D_G to l₂/2, where D_G presents diameter of circle with the same area as area of injector, through which the first counted screened jet of first oxidiser is injected. Diameter of circle with the same area as the area of injector, through which the second oxidiser is injected, that is D₂, makes from 10 to 60 mm. Diameter of circle with the same area as the area of injector, through which the second counted jet of first oxidiser, that is D₁, makes from 15 to 70 mm. Total quantity of second oxidiser makes from 50 to 90% of total quantity of injected oxidiser. Speeds of injection of second counted jet of first oxidiser and jet of second oxidiser are less or equal to 200 m/sec. Method is used for combustion of vitreous feeding, at that speeds of injection of second counted jet of first oxidiser and jet of second oxidiser are less or equal to 100 m/sec. Weight speed of first counted screened jet of first oxidiser makes from 10 to 20% of weight speed of total jet of first and second oxidisers.

EFFECT: reduction of nitrogen oxide formation with maintenance of flame stability.

12 cl, 5 dwg