Method of making a gypsum panel using a thermal oxidizer

Patent metadata

Field	Value
Publication number	US-12545621-B2
Application number	US-202217972657-A
Country	US
Kind code	B2
Filing date	Oct 25, 2022
Priority date	Oct 26, 2021
Publication date	Feb 10, 2026
Grant date	Feb 10, 2026

Abstract

The present invention is directed to a method of making such gypsum panel. For instance, the method comprises: providing a first facing material; providing a gypsum slurry including calcium sulfate hemihydrate, water, and a silicon containing compound onto the first facing material; providing a second facing material onto the gypsum slurry to form a continuous gypsum sheet; allowing the calcium sulfate hemihydrate to hydrate to form calcium sulfate dihydrate; cutting the continuous gypsum sheet to form a gypsum panel; supplying the gypsum panel to a heating or drying device; and providing a gaseous mixture from the heating or drying device to a regenerative thermal oxidizer.

First claim

The invention claimed is:

1 . A method of making a gypsum panel, the method comprising:
providing a first facing material; providing a gypsum slurry including calcium sulfate hemihydrate, water, and a silicon containing compound onto the first facing material; providing a second facing material onto the gypsum slurry to form a continuous gypsum sheet; cutting the continuous gypsum sheet to form a gypsum panel; supplying the gypsum panel to a heating or drying device; and providing a gaseous mixture from the heating or drying device to a regenerative thermal oxidizer, wherein a silica particulate emission in the gaseous mixture prior to entering the thermal oxidizer is 0.035 gr/dscf or less.

2 . The method of claim 1 , wherein the silicon containing compound comprises a siliconate.

3 . The method of claim 2 , wherein the siliconate has the following structure:

wherein
R 1 is H, halogen, alkyl, aryl, heteroaryl, cycloalkyl, haloalkyl, haloaryl, perhaloalkyl, or perhaloaryl; and
M is an alkali metal.

4 . The method of claim 3 , wherein R; is alkyl.

5 . The method of claim 2 , wherein the siliconate comprises sodium methylsiliconate, sodium ethylsiliconate, potassium ethylsiliconate, sodium propylsiliconate, potassium propylsiliconate, sodium isopropylsiliconate, potassium isopropylsiliconate, sodium butylsiliconate, potassium butylsiliconate, sodium hexylsiliconate, potassium hexylsiliconate, sodium octylsiliconate, potassium octylsiliconate, or a mixture thereof.

6 . The method of claim 2 , wherein the siliconate comprises potassium methylsiliconate.

7 . The method of claim 1 , wherein the silicon containing compound comprises silica fume.

8 . The method of claim 1 , wherein the gypsum slurry further comprises a siloxane.

9 . The method of claim 8 , wherein the siloxane has the following structure:

wherein,
n is an integer greater than 1; and
R 2 and R 3 are independently hydrogen, halogen, alkyl, cycloalkyl, aryl, heteroaryl, haloalkyl, haloaryl, alkoxy, carboxyalkyl, or alkenyl.

10 . The method of claim 9 , wherein R 2 and R 3 are independently hydrogen, halogen, alkyl, or cycloalkyl.

11 . The method of claim 8 , wherein the siloxane comprises dimethyidiphenylpolysiloxane, dimethyl/methylphenylpolysiloxane, polymethylphenylsiloxane, methylphenyl/dimethylsiloxane, vinyldimethyl terminated polydimethylsiloxane, vinylmethyl/dimethylpolysiloxane, vinyldimethyl terminated vinylmethyl/dimethylpolysiloxane, divinylmethyl terminated polydimethylsiloxane, vinylphenylmethyl terminated polydimethylsiloxane, dimethylhydro terminated polydimethylsiloxane, methylhydro/dimethylpolysiloxane, methylhydro terminated methyloctylpolysiloxane, methylhydro/phenylmethyl polysiloxane, fluoro-modified polysiloxane, or a mixture thereof.

12 . The method of claim 8 , wherein the siloxane comprises polydimethylsiloxane.

13 . The method of claim 8 , wherein the siloxane comprises polymethylhydrogensiloxane.

14 . The method of claim 8 , wherein the siloxane is cross-linked within the gypsum slurry and has a molecular weight of from 500 g/mol to 4,000,000 g/mol.

15 . The method of claim 8 , wherein the weight ratio of the siloxane to the silicon containing compound is from 0.0001 to 50.

16 . The method of claim 1 , wherein the gypsum slurry comprises a pH modifier.

17 . The method of claim 16 , wherein the pH modifier comprises caustic soda, magnesium oxide, sodium silicate, or a mixture thereof.

18 . The method of claim 16 , wherein the pH modifier comprises Portland cement.

19 . The method of claim 16 , wherein the pH modifier comprises lime.

20 . The method of claim 16 , wherein the pH modifier comprises a hydroxide.

21 . The method of claim 1 , wherein the gaseous mixture includes solid particulates.

22 . The method of claim 1 , wherein the gaseous mixture is provided through a conduit to the regenerative thermal oxidizer.

23 . The method of claim 1 , wherein the gaseous mixture is filtered prior to entering the regenerative thermal oxidizer.

Assignees

• Gold Bond Building Products Llc

Inventors

• Bland Brian
• Phipps James
• Stav Eli

Classifications

• B29C65/02

  by heating, with or without pressure · CPC title

• C04B22/064

  of the alkaline-earth metals · CPC title

• B28B19/0092

  to webs, sheets or the like, e.g. of paper, cardboard · CPC title

• C04B40/0071

  making use of a rise in pressure · CPC title

• C04B2111/0062

  Gypsum-paper board like materials · CPC title