Abstract: 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 mate

Abstract: The invention relates to a method of making a mineral melt comprising providing a circulating combustion chamber (1) which comprises an upper zone (2), a lower zone (3) and a base zone (4), injecting particulate fuel, particulate mineral material and primary combustion gas which has optionally an oxygen level of at least 25% by volume into the upper zone of the circulating combustion chamber so that the fuel undergoes pyrolysis in the upper zone to produce char, thereby melting the particulate mineral materials to form a mineral melt and generating exhaust gases, injecting secondary combustion gas which has optionally an Oxygen level of at least 25% by volume into the lower zone of the circulating combustion chamber so that the char combusts, thereby completing combustion of the fuel, and separating the mineral melt from the hot exhaust gases so that the hot exhaust gases pass though an outlet in the circulating combustion chamber and the mineral melt collects in the base zone.

Abstract: The present invention relates to a method of making mineral fibers, comprising providing a circulating combustion chamber (1) which comprises a top section (2), a bottom section (3) and a base section (4), injecting primary fuel, particulate mineral material and primary combustion gas into the top section of the circulating combustion chamber and combusting the primary fuel thereby melting the particulate material to form a mineral melt and generating exhaust gases, separating the mineral melt from the exhaust gases wherein the exhaust gases pass through an outlet (8) in the circulating combustion chamber and the mineral melt collects in the base section of the circulating combustion chamber, injecting secondary fuel, which comprises liquid or gaseous fuel, and secondary combustion gas into the bottom section of the circulating combustion chamber to form a flame in the bottom section which heats the melt, and flowing a stream of the collected melt through an outlet (15) in the base section to a centrifugal fi

Abstract: A process for making a mineral melt comprising: providing a circulating combustion chamber which contains circulating chamber gases, injecting a stream of particulate fuel into the combustion chamber through a fuel feed pipe, injecting combustion gas into the combustion chamber; mixing the stream of particulate fuel with the combustion gas and with the circulating chamber gases by injecting into the combustion chamber secondary gas, through a secondary gas inlet, wherein the secondary gas is injected adjacent to the stream of particulate fuel and the injection speed of the secondary gas is at least 100 m/s greater than the injection speed of the particulate fuel; suspending particulate mineral material in the circulating chamber gases and combusting the fuel, thereby melting the particulate mineral material and forming a mineral melt and hot exhaust gases; and separating the hot exhaust gases from the melt and collecting the melt.

Abstract: The present invention relates to a method of making mineral fibres, comprising providing a circulating combustion chamber (1) which comprises a top section (2), a bottom section (3) and a base section (4), injecting primary fuel, particulate mineral material and primary combustion gas into the top section of the circulating combustion chamber and combusting the primary fuel thereby melting the particulate material to form a mineral melt and generating exhaust gases, separating the mineral melt from the exhaust gases wherein the exhaust gases pass through an outlet (8) in the circulating combustion chamber and the mineral melt collects in the base section of the circulating combustion chamber, injecting secondary fuel, which comprises liquid or gaseous fuel, and secondary combustion gas into the bottom section of the circulating combustion chamber to form a flame in the bottom section which heats the melt, and flowing a stream of the collected melt through an outlet (15) in the base section to a centrifugal fi

Abstract: The invention relates to a method of making a mineral melt comprising providing a circulating combustion chamber (1) which comprises an upper zone (2), a lower zone (3) and a base zone (4), injecting particulate fuel, particulate mineral material and primary combustion gas which has optionally an oxygen level of at least 25% by volume into the upper zone of the circulating combustion chamber so that the fuel undergoes pyrolysis in the upper zone to produce char, thereby melting the particulate mineral materials to form a mineral melt and generating exhaust gases, injecting secondary combustion gas which has optionally an Oxygen level of at least 25% by volume into the lower zone of the circulating combustion chamber so that the char combusts, thereby completing combustion of the fuel, and separating the mineral melt from the hot exhaust gases so that the hot exhaust gases pass though an outlet in the circulating combustion chamber and the mineral melt collects in the base zone.