Abstract: A method for heat treatment of a grain-shaped feed material uses a calcination device in order to remove carbonate or water of crystallization from the feed material. In order to continuously check the quality of the heat treatment process, the bulk density of the heat-treated material is measured continuously, wherein upon detection of a deviation of the determined bulk density from the at least one desired bulk density at least one heat treatment parameter of the heat treatment is adapted automatically or manually.

Abstract: A method for heat treatment of a grain-shaped feed material uses a calcination device in order to remove carbonate or water of crystallization from the feed material. In order to continuously check the quality of the heat treatment process, the bulk density of the heat-treated material is measured continuously, wherein upon detection of a deviation of the determined bulk density from the at least one desired bulk density at least one heat treatment parameter of the heat treatment is adapted automatically or manually.

Abstract: A method for heat treatment of a grain-shaped feed material using a calcination device to remove carbonate or water of crystallization from the feed material are provided. To continuously check the quality of the heat treatment process, the bulk density of the heat-treated material is measured continuously, wherein upon detection of a deviation of the determined bulk density from the at least one desired bulk density at least one heat treatment parameter of the heat treatment is adapted automatically or manually.

Abstract: The invention relates to a method for producing an expanded granulate (29) made of a sand grain-shaped mineral material (1) using a propellant; wherein the material (1) is fed to a substantially upright furnace (2); wherein the material (1) is conveyed along a conveying path (4) through a plurality of vertically separated healing zones (5) in a furnace shaft (3) of the furnace (2), wherein each heating zone (5) can be heated by at least one independently controllable heating element (6); wherein the material (1) is heated to a critical temperature at which the surfaces (7) of the sand grains (1) become plastic and the sand grains (1) are expanded through the propellant.

Abstract: A method for producing an expanded granulate made of a sand grain-shaped mineral material uses a propellant. The material is transported along a transport path through multiple heating zones in a furnace shaft, heated to a critical temperature at which the surfaces of the sand grains plasticize, and the sand grains are expanded based on the propellant. The material is fed from the bottom together with an amount of air; the material is transported from the bottom to the top along the transport path by the air quantity which flows from the bottom to the top in the furnace shaft and the sand grains are expanded in the upper half of the transport path. The material is heated such that the material immediately prior to entering into the furnace shaft is at a material entry temperature lower than the critical temperature and higher than the ambient temperature.

Abstract: A method for heat treatment of a grain-shaped feed material using a calcination device to remove carbonate or water of crystallization from the feed material are provided. To continuously check the quality of the heat treatment process, the bulk density of the heat-treated material is measured continuously, wherein upon detection of a deviation of the determined bulk density from the at least one desired bulk density at least one heat treatment parameter of the heat treatment is adapted automatically or manually.

Abstract: The invention relates to a method for the expansion of sand grain-shaped raw material (1) in which the raw material (1) drops downwards through a substantially vertical heated shaft (4) provided with means (2) for forming a temperature profile (3), in which a shaft flow (5) prevails wherein the raw material (1) expands as a result of heat transfer in the shaft (4) to form expanded granulate (6) and the granulate formed (6) is passed into a pneumatic conveying line (7) with a conveying flow (8) for further transport. In order to continuously check the quality of the expansion process, the bulk density of the expanded granulate (6) is measured continuously, wherein upon detecting a deviation from at least one defined bulk density, the temperature profile (3) in the shaft (4) is adapted automatically or manually and/or the feeding of raw material (1) into the shaft (4) is reduced automatically or manually.

Abstract: The invention relates to a method for the expansion of sand grain-shaped raw material (1) in which the raw material (1) drops downwards through a substantially vertical heated shaft (4) provided with means (2) for forming a temperature profile (3), in which a shaft flow (5) prevails wherein the raw material (1) expands as a result of heat transfer in the shaft (4) to form expanded granulate (6) and the granulate formed (6) is passed into a pneumatic conveying line (7) with a conveying flow (8) for further transport. In order to continuously check the quality of the expansion process, the bulk density of the expanded granulate (6) is measured continuously, wherein upon detecting a deviation from at least one defined bulk density, the temperature profile (3) in the shaft (4) is adapted automatically or manually and/or the feeding of raw material (1) into the shaft (4) is reduced automatically or manually.

Abstract: A method and system for expanding sand grain-shaped raw material drops raw material downwards through a substantially vertical heated shaft equipped for forming a temperature profile, in which a shaft flow prevails wherein raw material expands as a result of heat transfer in the shaft to form expanded granulate, and the granulate formed is passed into a pneumatic conveying line with a conveying flow for further transport. The method and system continuously measure the bulk density of the expanded granulate to continuously check the quality of the expansion process, automatically or manually adapting the temperature profile in the shaft and/or automatically or manually reducing the feeding of raw material into the shaft upon detecting a deviation from at least one defined bulk density.

Abstract: The invention relates to an apparatus (10) for producing an expanded granulate from sand-grain-shaped material (1), comprising a furnace (2) with a substantially vertically extending furnace shaft (3) and a feed device (5) arranged above or in the upper region of the furnace shaft (3) for feeding the sand-grain-shaped material (1) to the furnace shaft (3). In order to achieve uniform expansion of the sand-grain-shaped material, the feed device (8) is formed to introduce the sand-grain-shaped material (1) in form of at least one downwardly falling curtain into the upper region of the furnace shaft (3), wherein the drop section (4) of the curtain (25) lies in a decentralised, preferably peripheral region of the furnace shaft cross-section. The invention also relates to a method for producing an expanded granulate from sand-grain-shaped mineral material.

Abstract: The invention relates to a method for producing an expanded granulate (29) made of a sand grain-shaped mineral material (1) using a propellant; wherein the material (1) is fed to a substantially upright furnace (2); wherein the material (1) is conveyed along a conveying path (4) through a plurality of vertically separated healing zones (5) in a furnace shaft (3) of the furnace (2), wherein each heating zone (5) can be heated by at least one independently controllable heating element (6); wherein the material (1) is heated to a critical temperature at which the surfaces (7) of the sand grains (1) become plastic and the sand grains (1) are expanded through the propellant.

Abstract: The invention relates to a method for the expansion of sand grain-shaped raw material (1) in which the raw material drops downwards through a substantially vertical heated shaft (3) provided with means (2) for heating, in which a shaft flow (4) prevails and to a dosing element (6) which can be connected to a substantially vertical shaft (3) and a conveying line (7). In order to prevent the pressure fluctuations coming from the conveying line (7) in the area of the shaft (3), a dosing element (6) is attached between the shaft and the conveying (7) line, in which the quantity of granulate which goes over from the shaft (3) into the conveying line (7) is regulated via means for regulating so that a defined material collection of the granulate is formed as a buffer in the dosing element (6), which decouples the shaft flow (4) from the conveying flow.

Abstract: The invention relates to a method for producing an expanded granulate from sand grain-shaped mineral material (1) with a propellant, wherein the material (1) is fed into a vertically upright furnace (2) from above and said material (1) falls along a drop section (4) through multiple heating zones (5) in a furnace shaft (3) of the furnace (2), wherein each heating zone (5) is heatable using at least one independently controllable heating element (6), and the material (1) is heated to a critical temperature at which the surfaces (7) of the sand grains (15) plasticize and the sand grains (15) are expanded by the propellant.

Abstract: The invention relates to a method for the expansion of sand grain-shaped raw material (1) in which the raw material drops downwards through a substantially vertical heated shaft (3) provided with means (2) for heating, in which a shaft flow (4) prevails and to a dosing element (6) which can be connected to a substantially vertical shaft (3) and a conveying line (7). In order to prevent the pressure fluctuations coming from the conveying line (7) in the area of the shaft (3), a dosing element (6) is attached between the shaft and the conveying (7) line, in which the quantity of granulate which goes over from the shaft (3) into the conveying line (7) is regulated via means for regulating so that a defined material collection of the granulate is formed as a buffer is the dosing element (6), which decouples the shaft flow (4) from the conveying flow.

Abstract: The invention relates to a method for the expansion of sand grain-shaped raw material (1) in which the raw material drops downwards through a substantially vertical heated shaft (3) provided with means (2) for heating, in which a shaft flow (4) prevails and to a dosing element (6) which can be connected to a substantially vertical shaft (3) and a conveying line (7). In order to prevent the pressure fluctuations coming from the conveying line (7) in the area of the shaft (3), a dosing element (6) is attached between the shaft and the conveying (7) line, in which the quantity of granulate which goes over from the shaft (3) into the conveying line (7) is regulated via means for regulating so that a defined material collection of the granulate is formed as a buffer in the dosing element (6), which decouples the shaft flow (4) from the conveying flow.

Abstract: The invention relates to an apparatus (10) for producing an expanded granulate from sand-grain-shaped material (1), comprising a furnace (2) with a substantially vertically extending furnace shaft (3) and a feed device (5) arranged above or in the upper region of the furnace shaft (3) for feeding the sand-grain-shaped material (1) to the furnace shaft (3). In order to achieve uniform expansion of the sand-grain-shaped material, the feed device (8) is formed to introduce the sand-grain-shaped material (1) in form of at least one downwardly falling curtain into the upper region of the furnace shaft (3), wherein the drop section (4) of the curtain (25) lies in a decentralised, preferably peripheral region of the furnace shaft cross-section. The invention also relates to a method for producing an expanded granulate from sand-grain-shaped mineral material.

Abstract: The invention relates to a method for producing an expanded granulate from sand grain-shaped mineral material (1) with a propellant, wherein the material (1) is fed into a vertically upright furnace (2) from above and said material (1) falls along a drop section (4) through multiple heating zones (5) in a furnace shaft (3) of the furnace (2), wherein each heating zone (5) is heatable using at least one independently controllable heating element (6), and the material (1) is heated to a critical temperature at which the surfaces (7) of the sand grains (15) plasticize and the sand grains (15) are expanded by the propellant.