Abstract: The present invention relates to a method and equipment for recovering heat from exhaust gas removed from an industrial process, such as an electrolysis process for the production of aluminum. Heat is recovered by means of an extraction/suction system, where the exhaust gas contains dust and/or particles. The heat is recovered as the exhaust gas being brought into contact with heat-recovery elements. Flow conditions and the design of the heat recovery elements are such that the deposits of the dust and/or particles on the surfaces stated are kept at a stable, limited level. In preferred embodiments, the heat-recovery elements have a circular or an extended, elliptical cross-section and may be equipped with fins or ribs.

Abstract: The present invention relates to a method and equipment for recovering heat from exhaust gas removed from an industrial process, such as an electrolysis process for the production of aluminium. Heat is recovered by means of an extraction/suction system, where the exhaust gas contains dust and/or particles. The heat is recovered as the exhaust gas being brought into contact with heat-recovery elements. Flow conditions and the design of the heat recovery elements are such that the deposits of the dust and/or particles on the surfaces stated are kept at a stable, limited level. In preferred embodiments, the heat-recovery elements have a circular or an extended, elliptical cross-section and may be equipped with fins or ribs.

Abstract: A method for burning gas in a burner, including leading the gas through an inner fuel tube and introduction of combustion air through an annular space surrounding the inner fuel tube. This space forms of an outer tube terminated by a conically converging section, wherein the end of the inner fuel tube forms a burner head. The major part of the primary gas is introduced into the upstream end of the burner head, to go into the combustion air that flows past the burner head, whereas a smaller part of a secondary gas is introduced into the free end of the burner head and into the constricted part of the annular channel that surrounds the burner head. The gas flow is accelerated past the burner head due to the reducing cross section and is burned downstream in relation to the burning head.

Abstract: A method for burning gas in a burner, including leading the gas through an inner fuel tube (13) and introduction of combustion air through an annular space surrounding the inner fuel tube. This space forms of an outer tube (11) terminated by a conically converging section, wherein the end of the inner fuel tube forms a burner head (15). The major part of the primary gas is introduced into the upstream end of the burner head, to go into the combustion air that flows past the burner head, whereas a smaller part of a secondary gas is introduced into the free end of the burner head (15) and into the constricted part of the annular channel that surrounds the burner head. The gas flow is accelerated past the burner head due to the reducing cross section and is burned downstream in relation to the burning head, wherein the mixture has properties that reduces the formation of Nox at the same time as the combustion becomes complete. It is also described a burner for performing this method.

Abstract: The present invention relates to a method and equipment for recovering heat from exhaust gas removed from an industrial process, such as an electrolysis process for the production of aluminium. Heat is recovered by means of an extraction/suction system, where the exhaust gas contains dust and/or particles. The heat is recovered as the exhaust gas is brought into contact with heat-recovery elements. Flow conditions and the design of the heat recovery elements are such that the deposits of the dust and/or particles on the surfaces stated are kept at a stable, limited level. In preferred embodiments, the heat-recovery elements have a circular or an extended, elliptical cross-section and may be equipped with fins or ribs.