The present invention relates to a process for melting solid batch material, comprising the steps of introducing solid batch material into a melter, and melting the solid batch material in the melter by submerged combustion and subjecting the melt to a flow pattern which when simulated on a computer by making use of common fluid dynamic equations shows a substantially toroidal melt flow pattern in the melt, comprising a major centrally inwardly convergent flow at the melt surface, the central axis of revolution of the toroid being substantially vertical. The invention further relates to a melter assembly for carrying out the process. The toroidal melt flow pattern is achieved by suitable arrangement, angle and spacing of multiple submerged combustion burners in the floor of the melter.

The present invention relates to a process for producing a boron containing glass, comprising melting raw materials including boron compounds in a submerged combustion melter withdrawing flue gases from said melter and recovering heat from said flue gases in appropriate heat recovery equipment prior to release into the environment.

The present invention relates to a process for producing a boron containing glass, comprising melting raw materials including boron compounds in a submerged combustion melter withdrawing flue gases from said melter and recovering heat from said flue gases in appropriate heat recovery equipment prior to release into the environment.

An oxy-fuel burner and method of use, having a housing defining an oxidizing-agent supply channel running in the longitudinal direction to the downstream end of the housing, a fuel supply channel likewise running in the longitudinal direction of the housing and an oxidant injector running in the longitudinal direction inside the fuel supply channel as well as an ignition and flame-control electrode inside the oxidizing-agent supply channel, the ignition and flame-control electrode being designed to provide initial ignition of the burner and subsequent control of the flame, and being connectable to a system for automatically controlling burner ignition and flame control.

A method and an apparatus for making a mineral melt having a cyclone furnace and a separating cyclone, said apparatus further having a device for supplying pre-heated particulate mineral material from a bottom of the separating cyclone to an inlet of the cyclone furnace. A material receiving conduit adapted for receiving the pre-heated particulate mineral material from the bottom outlet of the separating cyclone, in which the material receiving conduit has a first pressure. An outlet conduit supplying the particulate mineral material to the inlet of the cyclone furnace having a second pressure, wherein said second pressure is higher than said first pressure, and the particulate mineral material is fluidised and flows from the material receiving conduit to the outlet conduit. A gas-lock valve is provided between said material receiving conduit and said outlet conduit.

The invention relates to a submerged combustion burner (1) and to a melter comprising submerged combustion burners (1). The burner comprises a substantially parallelepipedic body, the melt oriented face of which shows a longitudinal slot, two opposite walls of the slot comprising a series of nozzles each supplied separately with fuel and oxygen containing gas. The slot advantageously shows a narrow opening comprised between 10 and 30 mm, preferably between 15 and 25 mm, most preferably about 20 mm. The burner is advantageously made of steel plates, preferably high temperature resistant steel. The walls of the slot as well as the melt oriented face of the burner are advantageously cooled. According to the invention, the parallelepipedic burner body comprises a first external longitudinal volume showing a generally U-shaped cross-section and a second internal longitudinal volume fitted within the said first external longitudinal volume, showing also a generally U-shaped cross-section, one of the longitudinal volumes comprising a connection to a supply of oxygen and the other comprising a connection to a supply of fuel gas. The ends of the branches of the longitudinal volumes are connected to the burner nozzles. A flange is arranged around the parallelepipedic burner body at a distance from the melt oriented face of said body.

The invention relates to a submerged combustion burner (1) and to a melter comprising submerged combustion burners (1). The burner comprises a substantially parallelepipedic body, the melt oriented face of which shows a longitudinal slot, two opposite walls of the slot comprising a series of nozzles each supplied separately with fuel and oxygen containing gas. The slot advantageously shows a narrow opening comprised between 10 and 30 mm, preferably between 15 and 25 mm, most preferably about 20 mm. The burner is advantageously made of steel plates, preferably high temperature resistant steel. The walls of the slot as well as the melt oriented face of the burner are advantageously cooled. According to the invention, the parallelepipedic burner body comprises a first external longitudinal volume showing a generally U-shaped cross-section and a second internal longitudinal volume fitted within the said first external longitudinal volume, showing also a generally U-shaped cross-section, one of the longitudinal volumes comprising a connection to a supply of oxygen and the other comprising a connection to a supply of fuel gas. The ends of the branches of the longitudinal volumes are connected to the burner nozzles. A flange is arranged around the parallelepipedic burner body at a distance from the melt oriented face of said body.

The present invention relates to an apparatus and a method of making a mineral melt, the method comprising the steps of providing a circulating combustion chamber (1); injecting fuel, preheated mineral material and combustion gas into the circulating combustion chamber (1); combusting the fuel in the circulating combustion chamber (1) thereby melting the mineral material to form a mineral melt and generating exhaust gases; separating the exhaust gases from the mineral melt, collecting the mineral melt (9) and passing the exhaust gases (10) to a heat exchange system, the method being characterised in that the mineral material comprises a first mineral material and a second mineral material wherein the first mineral material has a higher sintering temperature than the second mineral material and the first and second mineral materials are provided separately to the heat exchange system, wherein the first mineral material is preheated through contact with the exhaust gases and subsequently the second mineral material is preheated through contact with the exhaust gases and the preheated first mineral material.

The present invention relates to an apparatus and a method of making a mineral melt, the method comprising the steps of providing a circulating combustion chamber (1); injecting fuel, preheated mineral material and combustion gas into the circulating combustion chamber (1); combusting the fuel in the circulating combustion chamber (1) thereby melting the mineral material to form a mineral melt and generating exhaust gases; separating the exhaust gases from the mineral melt, collecting the mineral melt (9) and passing the exhaust gases (10) to a heat exchange system, the method being characterised in that the mineral material comprises a first mineral material and a second mineral material wherein the first mineral material has a higher sintering temperature than the second mineral material and the first and second mineral materials are provided separately to the heat exchange system, wherein the first mineral material is preheated through contact with the exhaust gases and subsequently the second mineral material is preheated through contact with the exhaust gases and the preheated first mineral material.

The claims define a submerged combustion melter comprising a submerged combustion burner (1) comprising three concentric tubes, all being closed at one end and open at the same opposite end, the internal tube (3) being connected to a source of oxygen containing gas (7), the middle tube (9) surrounding the internal tube (3) being connected to a source of fuel gas (11), and the outer tube (15) being connected to a source (19) of oxygen containing gas. The claims are also directed to a method of introducing a flame and/or combustion products into a melt from a submerged combustion burner and also directed to the use of the burner as a submerged combustion burner in a melter.