Inhibition of Spontaneous Combustion in Low-Rank Coals
A method for treating coal to reduce spontaneous combustion by reducing an exothermic heat of adsorption after the coal has begun to dry and when the coal is subsequently exposed to a liquid water is described. A source of a fluid pressure of a diluted hydrocarbon mixture is provided. A hydrocarbon in the mixture is a hydrocarbon emulsion of mineral when the coal is subsequently exposed to a liquid water oil, fuel oil, asphalt, or coal tar emulsions. A volume of the diluted hydrocarbon mixture is applied to a stream of freshly-mined and undried coal to provide a water-proofing of the coal to prevent water uptake after exposure to precipitation or flooding during transport and storage of the coal. The treated coal is loaded into a bulk pile. A temperature change trend in the bulk pile is reversed wherein a temperature of the bulk pile trends towards an ambient temperature rather than trending to a temperature higher than the ambient temperature.
1 . A method for treating coal to reduce spontaneous combustion by reducing an exothermic heat of adsorption after the coal has begun to dry and when the coal is subsequently exposed to a liquid water comprising the steps of:
providing a source of a fluid pressure of a hydrocarbon; and
applying the hydrocarbon to a stream of coal.
2 . The method of claim 1 wherein the hydrocarbon is a hydrocarbon emulsion.
3 . The method of claim 2 wherein a low-level amount of the hydrocarbon emulsion is applied to the coal as a percentage of a weight of the coal.
4 . The method of claim 3 wherein the hydrocarbon emulsion is selected from the group consisting of: mineral oil, fuel oil, asphalt, and coal tar emulsions.
5 . The method of claim 4 wherein the coal is freshly-mined and un-dried.
6 . The method of claim 5 wherein the hydrocarbon emulsion reduces self-heating of the coal caused by exothermic heat of absorption.
7 . A method for treating coal to reduce spontaneous combustion by reducing an exothermic heat of adsorption after the coal has begun to dry and when the coal is subsequently exposed to a liquid water comprising the steps of:
providing a source of a fluid pressure of a silicone; and
applying the silicone to a stream of coal.
8 . The method of claim 7 wherein the silicone is a silicone emulsion.
9 . The method of claim 8 wherein a low-level amount of the silicone emulsion is applied to the coal as a percentage of a weight of the coal.
10 . A method for treating coal to reduce spontaneous combustion by reducing an exothermic heat of adsorption after the coal has begun to dry and when the coal is subsequently exposed to a liquid water comprising the steps of:
providing a source of a fluid pressure of a silane; and
applying the silane to a stream of coal.
11 . The method of claim 10 wherein a low-level amount of the silane is applied to the coal as a percentage of a weight of the coal.
12 . A method for treating coal to reduce spontaneous combustion by reducing an exothermic heat of adsorption after the coal has begun to dry and when the coal is subsequently exposed to a liquid water comprising the step of waterproofing a freshly-mined coal to prevent water uptake after exposure to precipitation or flooding during transport and storage of the freshly-mined coal.
13 . The method of claim 12 further comprising the steps of:
providing a source of a fluid pressure of a hydrocarbon; and
applying the hydrocarbon to a stream of freshly-mined and undried coal.
14 . The method of claim 13 wherein the applying step includes application of a low-level amount of the hydrocarbon as a percentage of the weight of the coal.
15 . The method of claim 14 wherein the hydrocarbon is a hydrocarbon emulsion.
16 . The method of claim 15 wherein the low-level amount of the hydrocarbon emulsion is not more than 2 lb (0.9 kg) per ton of the coal.
17 . The method of claim 16 wherein the hydrocarbon emulsion is diluted in liquid water prior to the applying step.
18 . The method of claim 17 wherein a diluted mixture of the hydrocarbon emulsion and the liquid water contains less than 80 parts liquid water.
19 . The method of claim 18 wherein the diluted mixture contains between 19 and 79 parts liquid water.
20 . The method of claim 19 wherein an application rate of the diluted mixture is 2.5 to 10 gallons of diluted mixture per ton of freshly-mined and undried coal.
21 . The method of claim 20 wherein the hydrocarbon emulsion is selected from the group consisting of: mineral oil, fuel oil, asphalt, and coal tar emulsions.
22 . The method of claim 21 further comprising the step of:
developing a water repellency of the freshly-mined and undried coal by allowing the coal to dry under ambient conditions.
23 . The method of claim 21 further comprising the steps of:
loading the freshly-mined and undried coal into a bulk pile subsequent to the applying step; and
reversing a temperature change trend in the bulk pile wherein a temperature of the bulk pile trends towards an ambient temperature rather than trending to a temperature higher than the ambient temperature.
24 .- 36 . (canceled)