Abstract: The invention relates to a method of operating a furnace (1) comprising a flue pipe (11) for discharging the smoke, means (19) of introducing ambient air into the said flue pipe (11) and a smoke extractor (16) arranged in the said flue pipe (11). According to the method, the temperature of the smoke is measured at two points (31, 33), the temperature measured at the second point (33) is subtracted from the one measured at the first point (31), the result of the subtraction is compared with a datum value &Dgr;T, and the ratio of the flow rate of fuel to the flow rate of oxidizing agent introduced into the furnace (1) is decreased when the result of the subtraction is below the datum value &Dgr;T.

Abstract: Device for protecting an ejection outlet of a burner mounted through a wall of a furnace, comprising a peripheral heat shield around the ejection outlet of the burner comprising a consumable structure comprising a refractory material and a mounting for heat shield comprising a mover which moves the heat shield relative to the wall of the furnace, between at least two positions which are spaced apart along the axis of the burner.

Abstract: A device for atomizing a liquid fuel comprising a central liquid fuel feed passage for feeding with liquid fuel an outer atomizing-gas feed passage for feeding with atomizing gas, these being coaxial overall,an atomizing head extending said passages, the head being equipped for each fluid with one or more ducts which converge into one or more nozzles made in the head and emerging in a combustion region in which the nozzles release a mixture of atomized liquid fuel and of atomizing gas, which head is held at the end of the coaxial passages by a nut screwed onto a wall of the outer passage,wherein the central liquid-fuel feed passage is surrounded by the atomizing-gas feed passage and the atomizing head includes a skirt surrounding inlets to the ducts for the liquid fuel, which skirt is received inside the central passage and the skirt and the said passage respectively have externally and internally complementing cross sections.