초록 ▼

A method for preparing a modified beta-stucco from calcined natural rock gypsum that includes preparing a solution of liquid diethylene-triamine-pentaacetic acid in water, applying the solution onto beta-stucco while hot from the calciner, forming a wetted beta-stucco, and allowing the wetted stucco

A method for preparing a modified beta-stucco from calcined natural rock gypsum that includes preparing a solution of liquid diethylene-triamine-pentaacetic acid in water, applying the solution onto beta-stucco while hot from the calciner, forming a wetted beta-stucco, and allowing the wetted stucco to dry and heal, forming the modified beta-stucco.

대표청구항 ▼

1. A method for preparing a modified beta-stucco from calcined natural rock gypsum comprising: preparing a solution of liquid diethylene-triamine-pentaacetic acid in water;applying the solution onto said beta-stucco while hot from the calciner, forming a wetted stucco; andallowing the wetted stucco

1. A method for preparing a modified beta-stucco from calcined natural rock gypsum comprising: preparing a solution of liquid diethylene-triamine-pentaacetic acid in water;applying the solution onto said beta-stucco while hot from the calciner, forming a wetted stucco; andallowing the wetted stucco to dry and heal, forming the modified beta-stucco. 2. The method of claim 1 wherein the solution is applied at a rate of about 1.5 pounds to about 3.6 pounds DTPA per ton of beta-stucco (about 0.62 kg to about 1.45 kg DTPA per metric ton of beta-stucco). 3. The method of claim 1 further comprising grinding the modified beta-stucco. 4. The method of claim 1 further comprising fluidizing the beta-stucco prior to said applying step. 5. A method of claim 1 wherein said applying step further comprises: receiving beta-stucco at a temperature between about 285 to about 340° F. (about 140 to about 171° C.) into a treatment vessel;providing a fluidized bed at a bottom of the treatment vessel so that an air chamber of the vessel is pressurized;allowing the beta-stucco to traverse the vessel;passing the beta-stucco across at least one sprayer for a water and DTPA solution;spraying the beta-stucco with the solution to provide the modified beta-stucco; andremoving the modified beta-stucco from the treatment vessel. 6. The method of claim 5 further comprising agitating the beta-stucco as it enters the vessel with an agitator to prevent channeling of the fluidized bed. 7. The method of claim 5 wherein the beta-stucco is received into the treatment vessel at a top portion of the treatment vessel and allowed to traverse the vessel by descending to a bottom portion of the vessel. 8. The method of claim 6 wherein the descending beta-stucco is at least one of slowed down and suspended by the fluidized bed. 9. The method of claim 5 wherein the air chamber is pressurized to create a differential of about 2 psi to about 10 psi across the fluidized bed. 10. The method of claim 5 wherein the removing step further comprises removing the modified beta-stucco at a temperature between 160-300° F. (71-150° C.). 11. The method of claim 5 further comprising grinding the modified beta-stucco as it exits the treatment vessel.