US4252639A — Coal beneficiation processes

Claim 1

Independent Claim 188 words

A method of beneficiating raw coal to separate particles of product coal from particles of mineral matter associated therewith, said process comprising the steps of: conditioning said raw coal by agitating it in slurry with a surface active agent and with a halogenated C 1 or C 2 hydrocarbon in amounts and for a time sufficient to effect a transfer of moisture to the mineral matter, an agglomeration of the mineral matter particles, and the envelopment of the product coal particles with the surface active agent; transferring the conditioned coal to a separator containing a bath comprising a halogenated C 1 or C 2 hydrocarbon having a specific gravity intermediate those of the product coal and the mineral matter; maintaining the conditioned coal in said bath for a period of sufficient duration to effect the movement of the agglomerated mineral matter to the bottom of said bath and to effect the dispersion of the product coal particles in the bath and the migration of said particles to the top of the bath; and removing from said bath the product coal thus recovered from the mineral matter associated therewith.

Claim 2

Independent Claim 188 words

A method of beneficiating raw coal to separate particles of product coal from particles of mineral matter associated therewith, said process comprising the steps of: conditioning said raw coal by agitating it in slurry with a surface active agent and with a halogenated C 1 or C 2 hydrocarbon in amounts and for a time sufficient to effect a transfer of moisture to the mineral matter, an agglomeration of the mineral matter particles, and the envelopment of the product coal particles with the surface active agent; transferring the conditioned coal to a separator containing a bath comprising a halogenated C 1 or C 2 hydrocarbon having a specific gravity intermediate those of the product coal and the mineral matter; maintaining the conditioned coal in said bath for a period of sufficient duration to effect the movement of the agglomerated mineral matter to the bottom of said bath and to effect the dispersion of the product coal particles in the bath and the migration of said particles to the top of the bath; and removing from said bath the product coal thus recovered from the mineral matter associated therewith.

Claim 3

Dependent Claim 35 words

A method as defined in claim 1 in which said halogenated hydrocarbon is immiscible with water and has a specific gravity in the range of 1.2 to 2.2 and from two to six halogen atoms.

Claim 4

Dependent Claim 84 words

A method as defined in claim 2 in which the surface active agent is employed in said conditioning step in an amount ranging from 0.1 to 2 pounds per ton of raw coal and in an amount sufficiently large to form at least a monolayer on the particles of product coal but sufficiently small to avoid precipitation of said surface active agent in the aqueous phase in the slurry in which the conditioning takes place and the formation of a micellular aqueous phase therein.

Claim 5

Dependent Claim 19 words

A method as defined in claim 1 in which said product coal is recovered by dynamic density differential separation.

Claim 6

Dependent Claim 20 words

A method as defined in claim 1 in which said product coal is recovered by a static density differential separation.

Claim 7

Dependent Claim 38 words

A method as defined in claim 1 in which the moisture content of the raw coal is adjusted, if necessary, to a minimum of two percent based on the weight of said coal before the coal is conditioned.

Claim 8

Dependent Claim 78 words

A process as defined in claim 1 in which the raw coal constitutes from 50 to 80 weight percent of the constituents combined in the conditioning step and in which the concentration of surface active agent is sufficiently low to insure that the product coal particles are completely wet with a liquid surface active agent solution but sufficiently high to avoid long range diffusion of the surface active agent into the liquid phase generated in the conditioning step.

Claim 9

Dependent Claim 21 words

A process as defined in claim 1 in which said agitation is continued for a period of 0.2 to 5 minutes.

Claim 10

Independent Claim 81 words

A method of conditioning raw coal to facilitate the recovery of product coal particles from particles of mineral matter associated therewith, said method comprising the step of: agitating the raw coal with a surface active agent and a halogenated C 1 or C 2 hydrocarbon in amounts and for a time sufficient to effect a transfer of moisture to the mineral matter, an agglomeration of the mineral matter particles, and the envelopment of the product coal particles with surface active agent.

Claim 11

Independent Claim 81 words

A method of conditioning raw coal to facilitate the recovery of product coal particles from particles of mineral matter associated therewith, said method comprising the step of: agitating the raw coal with a surface active agent and a halogenated C 1 or C 2 hydrocarbon in amounts and for a time sufficient to effect a transfer of moisture to the mineral matter, an agglomeration of the mineral matter particles, and the envelopment of the product coal particles with surface active agent.

Claim 12

Dependent Claim 35 words

A method as defined in claim 9 in which said halogenated hydrocarbon is immiscible with water and has a specific gravity in the range of 1.2 to 2.2 and from two to six halogen atoms.

Claim 13

Dependent Claim 38 words

A method as defined in claim 9 in which the moisture content of the raw coal is adjusted, if necessary, to a minimum of two percent based on the weight of said coal before the coal is conditioned.

Claim 14

Dependent Claim 83 words

A method as defined in claim 9 in which the surface active agent is employed in said conditioning step in an amount ranging from 0.1 to 2 pounds per ton of raw coal and in an amount sufficiently large to form at least a monolayer on the particles of product but sufficiently small to avoid precipitation of said surface active agent in the aqueous phase of the slurry in which the conditioning takes place and the formation of a micellular aqueous phase therein.

Claim 15

Dependent Claim 78 words

A process as defined in claim 9 in which the raw coal constitutes from 50 to 80 weight percent of the constituents combined in the conditioning step and in which the concentration is sufficiently low to insure that the product coal particles are completely wet with the liquid in which the surface active agent is dissolved but sufficiently high to avoid long range diffusion of the surface active agent into the liquid phase generated in the conditioning step.

Claim 16

Dependent Claim 21 words

A process as defined in claim 9 in which said agitation is continued for a period of 0.2 to 5 minutes.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1984-02-24	1984-08-25	1985-02-24	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1988-02-24	1988-08-25	1989-02-24	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1992-02-24	1992-08-25	1993-02-24	$7700.00	Window Closed / Lapsed

Coal beneficiation processes

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