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US 4,904,277 AGranted
Rehydrating inhibitors for preparation of high-solids concentration low rank coal slurries
AssigneeTexaco Inc.
InventorsMitri S. Najjar, James R. Pascoe, Ralph Garcia
Life of this patent
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Abstract
A method for preparing a high-solids concentration low rank coal slurry by dehydrating the coal, treating the dehydrated coal with a rehydrating inhibitor such as a (C.sub.3 -C.sub.12) alcohol and adding a surfactant to the treated coal, whereby the concentration of the solids is increased from about 5 to about 20 wt. %.
Claims3
A method for preparing a high solids content low rank coal of a coal/water slurry for a coal gasification process which method comprises:
- (a) dehydrating a low rank coal feed with a solvent in the presence of an inert atmosphere of nitrogen at a temperature ranging from about 90.degree. to about 110.degree. C. and under a pressure of about 14.7 to about 1400 psi for a period of about 1.0 minute to about 1.0 hours;
- (b) treating said dehydrated coal with about 10.0 wt % by weight of said coal of an alkanol selected from the group consisting of butanol, pentanol, hexanol, 2-ethyl-hexanol, hexadecanol, decyl and lauryl alcohol or combinations thereof rehydrating inhibitor;
- and
- (c) adding between about 0.001 and about 3.0 wt. % of a surfactant to said treated coal, whereby the solids content of the coal/water slurry is increased from about 5 to about 20 wt. % and the BTU/lb of said coal feed is increased by about 5 percent to about 15 percent.
1 more element
A method for preparing a high solids content low rank coal of a coal/water slurry for a coal gasification process which method comprises:
- (a) dehydrating a low rank coal feed with a solvent in the presence of an inert atmosphere of nitrogen at a temperature ranging from about 90.degree. to about 110.degree. C. and under a pressure of about 14.7 to about 1400 psi for a period of about 1.0 minute to about 1.0 hour;
- (b) treating said dehydrated coal with about 10.0 wt % by weight of said coal of a poly methyl methacrylate rehydrating inhibitor;
- and
- (c) adding between about 0.001 and about 3.0 wt % of a surfactant to said treated coal, whereby the solids content of the coal/water slurry is increased from about 5 to about 20 wt. % and the BTU/lb of said coal feed is increased by about 5 percent to about 15 percent.
1 more element
Dependencies are inferred from the claim text.