A submerged combustion melter and burner therefor. The burner may include a first tube having a scaled distal end and a second tube concentric to the first tube, the second tube having a partially sealed distal end with an opening for receiving the first tube, where an annular space is defined between the first and second tubes. The burner further includes a first gas port in the sealed distal end of the first tube, the first gas port supplying a first gas, a second gas port in a distal end of the second tube, the second gas port supplying a second gas to the annular space, and a nozzle on the proximate ends of the first and second tubes. The nozzle provides N first gas outlets and M second gas outlets where the N first gas outlets supply either the first or the second gas into a molten glass environment external the burner, and the M second gas outlets supply either the second or the first gas into the molten glass environment external the burner to thereby mix and combust the first and second gases together in the molten glass environment.

A submerged burner for a glass- or rock-melting furnace, including a plurality of in-line injectors, each injector including a cylinder-shaped mixing chamber, with an ejection orifice, a fuel-supply duct and an oxidant-supply duct opening into the mixing chamber at the cylinder jacket in a direction causing a tangential flow of the fuel and of the oxidant relative to the cylinder jacket, and a duct system making it possible for a coolant to flow inside the burner, and, preferably on either side of the alignment of injectors, placed parallel to and all along the latter, solid metal sides rising from the injectors, and protective partitions situated on the top of the solid metal sides.

Apparatus includes a first and second conduits configured to form an annulus between them. An adjustable structure includes a body having an upper surface, a lower surface, and a circumferential surface abutting a portion of the internal surface of the second conduit. The structure is adjustable axially in relation to and removably attached to the first conduit via a hub. The hub defines a central passage for fuel or oxidant. The body has one or more non-central through passages configured such that flow of an oxidant or fuel therethrough causes the fuel or oxidant to intersect flow of fuel or oxidant exiting from the central passage in a region above the upper surface of the body.

A portion of a submerged combustion burner is disposed into a pressure vessel. The portion of the submerged combustion burner has a welded area that has a first microstructure defined by a first number of voids. The vessel is filled with an inert gas, pressurized, and heated. Pressurizing and heating operations are performed for a time and at a temperature and a pressure sufficient to produce a second microstructure in the welded area of the burner. The second microstructure is defined by a second number of voids less than the first number of voids.

Processes and systems for producing glass fibers having regions devoid of glass using submerged combustion melters, including feeding a vitrifiable feed material into a feed inlet of a melting zone of a melter vessel, and heating the vitrifiable material with at least one burner directing combustion products of an oxidant and a first fuel into the melting zone under a level of the molten material in the zone. One or more of the burners is configured to impart heat and turbulence to the molten material, producing a turbulent molten material comprising a plurality of bubbles suspended in the molten material, the bubbles comprising at least some of the combustion products, and optionally other gas species introduced by the burners. The molten material and bubbles are drawn through a bushing fluidly connected to a forehearth to produce a glass fiber comprising a plurality of interior regions substantially devoid of glass.

Apparatus includes a first and second conduits configured to form an annulus between them. An adjustable structure includes a body having an upper surface, a lower surface, and a circumferential surface abutting a portion of the internal surface of the second conduit. The structure is adjustable axially in relation to and removably attached to the first conduit via a hub. The hub defines a central passage for fuel or oxidant. The body has one or more non-central through passages configured such that flow of an oxidant or fuel therethrough causes the fuel or oxidant to intersect flow of fuel or oxidant exiting from the central passage in a region above the upper surface of the body.

A combustion burner employed in a submerged combustion vessel used to melt high index glass includes an arch positioned on a burner in the submerged combustion vessel. An amount of combustible gas flows through a first port disposed in a first haunch of the arch and through a second port disposed in a second haunch of the arch. Fuel is supplied through an end port in a fuel supply line. The end port is disposed under the arch. An amount of glass is fed into the submerged combustion vessel and is melted inside the submerged combustion vessel by igniting the burner. Some of the melted glass at least partially solidifies against a wall of the submerged combustion vessel such that the melted glass is contained in a vessel of itself.