Method For Calcining Gypsum and Making a Gypsum Board

Patent metadata

Field	Value
Publication number	US-2024254044-A1
Application number	US-202418409904-A
Country	US
Kind code	A1
Filing date	Jan 11, 2024
Priority date	Jan 19, 2023
Publication date	Aug 1, 2024
Grant date	—

Abstract

In general, the present invention is directed to a method of making a gypsum board. The method comprises: applying a phosphorus containing compound to a first gypsum composition to provide a phosphorus modified gypsum composition; calcining the phosphorus modified gypsum composition to provide a calcined gypsum composition; preparing a gypsum slurry by combining water and the calcined gypsum composition; depositing the gypsum slurry on a first facing material; providing a second facing material on the gypsum slurry; and allowing the calcined gypsum to convert to calcium sulfate dihydrate.

First claim

1 - 30 . (canceled)

31 . A method for making a gypsum board, the method comprising:
applying a phosphorus containing compound to a first gypsum composition to provide a phosphorus modified gypsum composition,
wherein the phosphorus containing compound comprises a phosphite, a phosphate having the formula P(O) n (X) m wherein n is from 0 to 4, m is from 0 to 6, the sum of n and m is from 3 to 6, and X is hydrogen, halogen, sulfur, or selenium, a salt thereof, or a mixture thereof;
calcining the phosphorus modified gypsum composition to provide a calcined gypsum composition; preparing a gypsum slurry by combining water and the calcined gypsum composition; depositing the gypsum slurry on a first facing material; providing a second facing material on the gypsum slurry; and allowing the calcined gypsum to convert to calcium sulfate dihydrate.

32 . The method of claim 31 , wherein the phosphorus containing compound comprises a phosphate having the formula P(O) n (X) m wherein n is from 0 to 4, m is from 0 to 6, the sum of n and m is from 3 to 6, and X is hydrogen, halogen, sulfur, or selenium, a salt thereof.

33 . The method of claim 32 , wherein X includes fluoro.

34 . The method of claim 32 , wherein n is from 2 to 3.

35 . The method of claim 32 , wherein m is from 1 to 2.

36 . The method of claim 31 , wherein the phosphorus containing compound comprises a halophosphate.

37 . The method of claim 31 , wherein the phosphorus containing compound comprises a salt including an alkali metal, an alkaline earth metal, a transition metal, or a combination thereof.

38 . The method of claim 31 , wherein the phosphorus containing compound comprises sodium monofluorophosphate.

39 . The method of claim 31 , wherein the gypsum slurry further comprises a foaming agent comprising an alkyl sulfate, an alkyl ether sulfate, or a mixture thereof.

40 . The method of claim 31 , wherein the first gypsum composition comprises reclaimed gypsum.

41 . The method of claim 31 , wherein the first gypsum composition comprises reclaimed gypsum and virgin gypsum.

42 . The method of claim 31 , wherein the first gypsum composition comprises an organosilicon compound.

43 . The method of claim 31 , wherein the first gypsum composition comprises a polysiloxane.

44 . The method of claim 31 , wherein the first gypsum composition comprises a polymethylhydrosiloxane.

45 . The method of claim 31 , wherein the first gypsum composition comprises reclaimed gypsum and an organosilicon compound.

46 . The method of claim 45 , wherein the organosilicon compound comprises a polysiloxane.

47 . The method of claim 45 , wherein the organosilicon compound comprises a polymethylhydrosiloxane.

48 . The method of claim 40 , further comprising combining the modified gypsum composition with virgin gypsum to provide a second gypsum composition, calcining the second gypsum composition to provide the calcined gypsum composition.

49 . The method of claim 45 , further comprising combining the modified gypsum composition with virgin gypsum to provide a second gypsum composition, calcining the second gypsum composition to provide the calcined gypsum composition.

50 . A gypsum board made from the method of claim 31 .

51 . A method for making a gypsum board, the method comprising:
applying a phosphorus containing compound to a first gypsum composition to provide a phosphorus modified gypsum composition,
wherein the first gypsum composition comprises reclaimed gypsum and an organosilicon compound,
wherein the phosphorus containing compound comprises a phosphite, a phosphate having the formula P(O) n (X) m wherein n is from 0 to 4, m is from 0 to 6, the sum of n and m is from 3 to 6, and X is hydrogen, halogen, sulfur, or selenium, a salt thereof, or a mixture thereof;
calcining the phosphorus modified gypsum composition to provide a calcined gypsum composition; preparing a gypsum slurry by combining water and the calcined gypsum composition; depositing the gypsum slurry on a first facing material; providing a second facing material on the gypsum slurry; and allowing the calcined gypsum to convert to calcium sulfate dihydrate.

52 . The method of claim 51 , wherein the first gypsum composition further comprises virgin gypsum.

53 . The method of claim 51 , further comprising combining the modified gypsum composition with virgin gypsum to provide a second gypsum composition, calcining the second gypsum composition to provide the calcined gypsum composition.

54 . A gypsum board made from the method of claim 51 .

Assignees

• Gold Bond Building Products Llc

Inventors

• Iyer R G
• Busche Bradley J
• Bailey Joseph J
• Hawk Jeff
• Fleming Jesse
• Mcnamar Matthew

Classifications

• C04B28/145

  Calcium sulfate hemi-hydrate with a specific crystal form · CPC title

• C04B11/024

  Ingredients added before, or during, the calcining process, e.g. calcination modifiers · CPC title

• C04B2111/0062

  Gypsum-paper board like materials · CPC title

• C04B11/005 Primary

  Preparing or treating the raw materials · CPC title

• C04B11/002

  Mixtures of different CaSO4-modifications, e.g. plaster of Paris and anhydrite, used as cements · CPC title