Abstract: The instant invention is concerned with the post-treatment of ?-hemihydrate plasters for the purpose of stabilization. The invention relies in the addition of a retardant to the calcined ?-hemihydrate. It is also the purpose of the invention to provide stabilized ?-hemihydrate plasters which exhibit advantageous properties.

Abstract: The instant invention is concerned with the post-treatment of ?-hemihydrate plasters for the purpose of stabilization. The invention relies in the addition of a retardant to the calcined ?-hemihydrate. It is also the purpose of the invention to provide stabilized ?-hemihydrate plasters which exhibit advantageous properties.

Abstract: A process for stabilizing plaster includes: a) providing a heated HH-plaster; b) feeding the hot plaster in a moistening device having walls heated to at least 100° C.; c) injecting water and/or steam into the moistening device in conditions that such not yet moistened surfaces of the plaster are exposed to the injected water and/or steam; d) maintaining an atmosphere in the moistening device at a level of the dew point in the range of 75 to 99° C.; e) feeding the moistened blend into a curing device; f) maintaining an atmosphere in the curing device above 75° C. for at least 3 minutes; g) feeding the moistened and cured blend into a drying device; and h) drying the moistened and cured blend. Also an apparatus for moistening ?-hemihydrate plaster includes a rotating drum with lifting blades inside where all walls in contact with the product are externally heated at a temperature above 100° C.

Abstract: The invention provides a process for stabilizing plaster and an apparatus for implementing the moistening part of the process. The process comprises the following steps: a) providing a heated HH-plaster preferably at temperatures over 100° C.; b) feeding the hot plaster in a moistening device having walls heated to at least 100° C.; c) injecting water and/or steam into the moistening device in conditions that such not yet moistened surfaces of the plaster are exposed to the injected water and/or steam; d) maintaining an atmosphere in the moistening device at a level of the dew point in the range of 75 to 99° C.; e) feeding the moistened blend into a curing device; f) maintaining an atmosphere in the curing device above 75° C. for at least 3 minutes; g) feeding the moistened and cured blend into a drying device; and h) drying said moistened and cured blend.

Abstract: The invention provides a process for stabilizing plaster and an apparatus for implementing the moistening part of the process. The process comprises the following steps: a) providing a heated HH-plaster preferably at temperatures over 100° C.; b) feeding the hot plaster in a moistening device having walls heated to at least 100° C.; c) injecting water and/or steam into the moistening device in conditions that such not yet moistened surfaces of the plaster are exposed to the injected water and/or steam; d) maintaining an atmosphere in the moistening device at a level of the dew point in the range of 75 to 99° C.; e) feeding the moistened blend into a curing device; f) maintaining an atmosphere in the curing device above 75° C. for at least 3 minutes; g) feeding the moistened and cured blend into a drying device; and h) drying said moistened and cured blend.

Abstract: The invention provides a process for stabilizing plaster and an apparatus for implementing the moistening part of the process. The process comprises the following steps: a) providing a heated HH-plaster preferably at temperatures over 100° C.; b) feeding the hot plaster in a moistening device having walls heated to at least 100° C.; c) injecting water and/or steam into the moistening device in conditions that such not yet moistened surfaces of the plaster are exposed to the injected water and/or steam; d) maintaining an atmosphere in the moistening device at a level of the dew point in the range of 75 to 99° C.; e) feeding the moistened blend into a curing device; f) maintaining an atmosphere in the curing device above 75° C. for at least 3 minutes; g) feeding the moistened and cured blend into a drying device; and h) drying said moistened and cured blend.