Method for the treatment of magnesia-carbon products
The invention relates to a method for treating magnesia-carbon products. The method includes providing magnesia-carbon products, wherein the magnesia-carbon products comprise magnesia and carbon, and wherein the magnesia-carbon products comprise proportions of Al 4 C 3 . The method also includes providing water and providing a gas comprising the following features: the gas comprises carbon dioxide; and the proportion of carbon dioxide in the gas is above the proportion of carbon dioxide in the air. Further, the method includes providing a container that encloses a space, and providing the magnesia-carbon products in the space. The method also includes subjecting the space to temperature and pressure while providing the water and the gas in the space.
1 . A method for the treatment of magnesia-carbon products, comprising the following method steps:
A. providing magnesia-carbon products comprising the following features:
A.1 the magnesia-carbon products comprise magnesia and carbon;
A.2 the magnesia-carbon products comprise proportions of Al 4 C 3 ;
B. providing water;
C. providing a gas comprising the following features:
C.1 the gas comprises carbon dioxide;
C.2 the proportion of carbon dioxide in the gas is above the proportion of carbon dioxide in the air;
D. providing a container that encloses a space;
E. providing the magnesia-carbon products in the space;
F. subjecting the space to
F.1 temperature; and
F.2 pressure in the range of 0.1 to 6 MPa
while providing the water and the gas in the space.
2 . The method of claim 1 , wherein the magnesia-carbon products are used magnesia-carbon products.
3 . The method according to claim 1 , wherein the magnesia-carbon products and the water are provided in the space in such proportions that in the space the molar ratio of water to Al 4 C 3 is at least 8 to 1.
4 . The method according to claim 1 , wherein the gas and the water are provided in such proportions in the space that in the space the molar ratio of carbon dioxide to water is at least 1 to 1.
5 . The method according to claim 1 , wherein, during the subjecting, the temperature is in the range of 100 to 320° C.
6 . The method according to claim 1 , wherein the gas is carbon dioxide gas.
7 . The method according to claim 1 , wherein the space enclosed by the container is sealed gas-tight after providing the magnesia-carbon products in the space.
8 . The method according to claim 1 , wherein the container is an autoclave.
9 . The method according to claim 1 , wherein the magnesia-carbon products comprise an Al 4 C 3 content of at least 0.1% by mass, based on a total mass of the magnesia-carbon products before the subjecting.
10 . The method according to claim 1 , wherein the magnesia-carbon products comprise a proportion of MgO of at least 69% by mass, based on a total mass of the magnesia-carbon products before the subjecting.
11 . The method according to claim 1 , wherein the magnesia-carbon products comprise a carbon content of at least 1% by mass, based on a total mass of the magnesia-carbon products before the subjecting.
12 . The method according to claim 1 , wherein the space is subjected to the temperature and the pressure such that at least a portion of the Al 4 C 3 decomposes during the subjecting.
13 . The method according to claim 12 , wherein the decomposed Al 4 C 3 reacts at least partially to form aluminum hydroxide.
14 . The method according to claim 1 , comprising the following further process steps:
G conveying treated magnesia-carbon products, after the subjecting, from the space;
H. mixing the treated magnesia-carbon products with one or more further substances to form a batch; and
I. producing a refractory product from the batch.