Method of treating earthen areas
AssigneeUnited States Gypsum Company
InventorsWalter Dan Kobeski, Sigismund Walter Srocki, William Ivan Blosser, James Joseph Needham
Life of this patent
Estimating the term…
Abstract
A method of treating barren earthen areas for inhibiting air and sun spoilation is disclosed, the method comprising forming an aqueous slurry of calcium sulfate hemihydrate with a small amount of defoamer using a quantity of water about 25-56% above normal consistency, the hemihydrate particles having a surface area of about 4,000-16,000 square centimeters per gram; and spraying the slurry onto the barren area to form a set, substantially air-impermeable covering to the barren area that will substantially exclude outside air from the area. The method is particularly applicable to controlling burning coal spoils and inhibiting spontaneous combustion of coal refuse banks.
Claims12
A method of preventing combustion in combustible earthen banks which comprises the steps of:
- (1) forming a composition consisting essentially of an aqueous slurry of calcium sulfate hemihydrate and a minor amount of a defoamer, the hemihydrate particles having a surface area of about 4000 to about 16,000 square centimeters per gram with less than about 0.5% by weight of greater than 50 mesh particles, the water being present in an amount of about 25% by volume to about 56% by volume above normal consistency for the hemihydrate;
- (2) applying said composition to the surface of the area to be treated;
- and
- (3) allowing the applied composition to set whereby there is formed a dense, substantially air-impermeable and non-porous layer substantially inhibiting gas flow and radiant heat from the surface of the treated area.
A method of treating burning coal banks for extinguishing combustion comprising the steps of:
- (1) forming a sprayable composition consisting essentially of an aqueous slurry of calcium sulfate hemihydrate and a minor amount of defoamer, the hemihydrate particles having a surface area of about 4,000 to about 16,000 square centimeters per gram and having a normal consistency of about 30 to about 95, the water being present in an amount of about 25 to about 56% above normal consistency for that hemihydrate;
- and
- (2) applying said composition to the surface of the coal bank so as to form a dense, set, substantially air-impermeable and non-porous layer of gypsum at least on the order of about 1/16 to 1 inch in thickness on that surface of the coal bank.
A method of treating combustible coal banks to inhibit spontaneous combustion therein comprising the steps of:
- (1) forming a sprayable composition consisting essentially of an aqueous slurry of calcium sulfate hemihydrate with a small amount of defoamer, the hemihydrate particles having a surface area of about 4000 to about 16,000 square centimeters per gram and having a normal consistency of about 34 to about 95 cubic centimeters of water per 100 grams of hemihydrate, the water being present in an amount of about 25 to about 56% above normal consistency for that hemihydrate;
- and
- (2) applying said composition to a portion of the combustible coal bank to form a dense, set, substantially air-impermeable and non-porous layer of gypsum at least on the order of 1/16 inch in thickness substantially excluding atmospheric air from the surface of the treated coal bank.
Dependencies are inferred from the claim text.