The invention relate to use of aqueous solution of organic ammonium carboxylate of formula (I): [NR.sup.1R.sup.2R.sup.3R.sup.4].sup.+n[R.sup.5(COO)].sup.n, in which R.sup.1, R.sup.2, and R.sup.3 are selected from the group composing of hydrogen and methyl, R.sup.4 is a C.sub.1-C.sub.4-alkyl substituted with a hydroxyl group, R.sup.5 is hydrogen or methyl and n is 1, as a mist or drops in preventing dusting of fine material and in lowering the freezing point of said aqueous solution on the surface of said fine material or on the surface of dust particles obtained from said fine material by spraying said mist or drops onto fine material or onto dust particles obtained from said fine material to neutralize negatively charged dust particles or by changing negatively charged dust particles into positively charged dust particles, wherein said fine material is selected from the group composing of sand, crushed stone, stone powder, crushed expanded clay, or crushed expanded clay aggregate, crushed cement or concrete, cement or concrete powder, chopped organic material, minerals and metal powder.

A composition for suppressing dust particles includes from about 51% to about 100% by weight of saturated hydrocarbons, and from about 0 to about 49% by weight of unsaturated hydrocarbons. The composition has a content of wax in the range from about 5% to about 40% by weight of the total composition. A method of making and a method of using such a composition are also provided.

A composition for suppressing dust particles includes from about 51% to about 100% by weight of saturated hydrocarbons, and from about 0 to about 49% by weight of unsaturated hydrocarbons. The composition has a content of wax in the range from about 5% to about 40% by weight of the total composition. A method of making and a method of using such a composition are also provided.

Disclosed is a physical-chemical composite inhibitor for controlling spontaneous combustion of low-rank coal, and methods of preparing and using the same. The composite inhibitor consists of a chelate and attapulgite, the chelate is generated by chelation of proanthocyanidin with calcium chloride. The composite inhibitor has moisture-absorbing and moisture-retaining effect, and can reduce water dissipation at low temperature. A stable oxide insulating layer such as MgO and Al.sub.2O.sub.3 insulating layer can be formed at high temperature, which can block a coal body from contacting with oxygen. In addition, the composite inhibitor can capture hydroxyl free radicals generated during the chain-cycle reaction and destroy peroxide free radicals, and can also interact with an active moiety in coal to form a stable structure such as ether linkage and hydrogen bonding, thereby achieving permanent inhibition of low-rank coal.

Disclosed is a physical-chemical composite inhibitor for controlling spontaneous combustion of low-rank coal, and methods of preparing and using the same. The composite inhibitor consists of a chelate and attapulgite, the chelate is generated by chelation of proanthocyanidin with calcium chloride. The composite inhibitor has moisture-absorbing and moisture-retaining effect, and can reduce water dissipation at low temperature. A stable oxide insulating layer such as MgO and Al.sub.2O.sub.3 insulating layer can be formed at high temperature, which can block a coal body from contacting with oxygen. In addition, the composite inhibitor can capture hydroxyl free radicals generated during the chain-cycle reaction and destroy peroxide free radicals, and can also interact with an active moiety in coal to form a stable structure such as ether linkage and hydrogen bonding, thereby achieving permanent inhibition of low-rank coal.

Methods are described for maintaining unpaved roads. The methods include applying an aqueous composition to a section of an unpaved road (such as a mine haul road in a mine). The aqueous composition includes from 5 to 10,000 ppm of a synthetic polymer in water, and may be applied periodically. The synthetic polymer may be compatible with chemical processes employed by the mine, and the method may also include subsequently mining the section of the mine haul road.

Methods are described for maintaining unpaved roads. The methods include applying an aqueous composition to a section of an unpaved road (such as a mine haul road in a mine). The aqueous composition includes from 5 to 10,000 ppm of a synthetic polymer in water, and may be applied periodically. The synthetic polymer may be compatible with chemical processes employed by the mine, and the method may also include subsequently mining the section of the mine haul road.

Disclosed is a physical-chemical composite inhibitor for controlling spontaneous combustion of low-rank coal, and methods of preparing and using the same. The composite inhibitor consists of a chelate and attapulgite, the chelate is generated by chelation of proanthocyanidin with calcium chloride. The composite inhibitor has moisture-absorbing and moisture-retaining effect, and can reduce water dissipation at low temperature. A stable oxide insulating layer such as MgO and Al.sub.2O.sub.3 insulating layer can be formed at high temperature, which can block a coal body from contacting with oxygen. In addition, the composite inhibitor can capture hydroxyl free radicals generated during the chain-cycle reaction and destroy peroxide free radicals, and can also interact with an active moiety in coal to form a stable structure such as ether linkage and hydrogen bonding, thereby achieving permanent inhibition of low-rank coal.

Disclosed is a physical-chemical composite inhibitor for controlling spontaneous combustion of low-rank coal, and methods of preparing and using the same. The composite inhibitor consists of a chelate and attapulgite, the chelate is generated by chelation of proanthocyanidin with calcium chloride. The composite inhibitor has moisture-absorbing and moisture-retaining effect, and can reduce water dissipation at low temperature. A stable oxide insulating layer such as MgO and Al.sub.2O.sub.3 insulating layer can be formed at high temperature, which can block a coal body from contacting with oxygen. In addition, the composite inhibitor can capture hydroxyl free radicals generated during the chain-cycle reaction and destroy peroxide free radicals, and can also interact with an active moiety in coal to form a stable structure such as ether linkage and hydrogen bonding, thereby achieving permanent inhibition of low-rank coal.

The present invention relates to the technical field of mine fire prevention and extinguishing, in particular to a liquid nitrogen direct injection and low-temperature foaming intelligent filling system based on mine fire area characteristics and an application method, comprising a liquid nitrogen storage tank, a liquid nitrogen direct injection system and a low-temperature foaming system, wherein the liquid nitrogen storage tank communicates with a liquid nitrogen pressurizing device through a main pipeline; a temperature control unit is arranged on the main pipeline; and the liquid nitrogen pressurizing device is connected with the liquid nitrogen direct injection system and the low-temperature foaming system, respectively, liquid nitrogen is directly injected into a foam liquid, to prepare a low-temperature foam type fire preventing and extinguishing material by means of forced convection, membrane boiling, explosion boiling and nucleate boiling between the liquid nitrogen and water.