System and method for calcining gypsum
View Patent ↗A system ( 100 ) for calcining natural gypsum, synthetic gypsum ( 112 ) or a combination thereof, the system including: a mill ( 114 ) for grinding and drying natural gypsum, synthetic gypsum ( 112 ) or a combination thereof, to produce dried gypsum ( 116 ); a flash calciner ( 118 ) for calcining the dried gypsum to produce an exhaust gas ( 130 ) and calcined gypsum ( 128 ); and a mechanism ( 134 ) for transporting at least a portion of the exhaust gas ( 130 ) produced by the flash calciner ( 118 ) to an air heater ( 126 ) that supplies hot gas ( 126 a ) to the flash calciner ( 118 ).
1. A system for calcining natural gypsum, synthetic gypsum or a combination thereof, the system comprising:
a mill for grinding and drying natural gypsum, synthetic gypsum or a combination thereof, to produce dried gypsum;
a flash calciner for calcining the dried gypsum to produce an exhaust gas and calcined gypsum; and
a mechanism for transporting at least a portion of the exhaust gas produced by the flash calciner to a first air heater that supplies hot gas to the flash calciner and to the mill.
2. A system according to claim 1 , wherein the mill is a roller mill.
3. A system according to claim 1 , wherein the mill is a hammer impact mill.
4. A system according to claim 1 , wherein the first air heater only provides hot gas to the calciner and further comprising a second air heater that provides hot gas to the mill.
5. A system according to claim 1 , further comprising a dust collector coupled to the mill.
6. A process for calcining natural gypsum, synthetic gypsum or a combination thereof, the process comprising:
supplying natural gypsum, synthetic gypsum or a combination thereof to a mill;
grinding and drying the natural gypsum, synthetic gypsum or a combination thereof in the mill to form dried gypsum and a first exhaust gas;
supplying the dried gypsum to a flash calciner;
calcining the dried gypsum in the flash calciner, thereby producing a second exhaust gas and calcined gypsum; and
transporting at least a portion of the second exhaust gas to a first air heater that provides hot gas to the flash calciner and to the mill.
7. A process according to claim 6 , wherein the mill is a roller mill.
8. A process according to claim 6 , wherein the mill is a hammer impact mill.
9. A process according to claim 6 further comprising transporting at least a portion of the first exhaust gas to a second air heater.
10. A process according to claim 9 , wherein the first air heater only provides hot gas to the calciner and the second air heater is coupled to the mill, and provides hot gas thereto.
11. A system for calcining gypsum, the system comprising:
a mill for grinding and drying gypsum, thereby producing dried gypsum and a first exhaust gas, wherein the mill is selected from a roller mill or a hammer impact mill, and further wherein the gypsum is selected from natural gypsum, synthetic gypsum or a combination thereof;
a flash calciner for calcining the dried gypsum, thereby producing calcined gypsum and a second exhaust gas; and
a mechanism for transporting the second exhaust gas produced by the flash calciner to a first air heater coupled to the flash calciner and to the mill.
12. A system according to claim 11 , further comprising a dust collector coupled to the mill.
13. A system according to claim 11 , further comprising a second air heater.
14. A system according to claim 13 , wherein the first air heater is only coupled to the flash calciner and the second air heater is coupled to the mill.
15. A system according to claim 13 , further comprising a mechanism for transporting the first exhaust gas to the second air heater.