Method for coal liquefaction
AssigneeUniversity of Utah
InventorsWendell H. Wiser, Alex G. Oblad, Joseph S. Shabtai
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Abstract
A process is disclosed for coal liquefaction in which minute particles of coal in intimate contact with a hydrogenation catalyst and hydrogen arc reacted for a very short time at a temperature in excess of 400.degree. C. at a pressure of at least 1500 psi to yield over 50% liquids with a liquid to gaseous hydrocarbon ratio in excess of 8:1.
Claims20
A method for converting more than 50% by weight coal to liquids wherein the ratio of liquids to hydrocarbon gases is greater than about 8:1, by weight comprising the steps of:
- introducing finely divided particles of coal into a thermal cracking zone having a temperature of at least 400.degree. C. and a pressure of at least of 1500 psi;
- introducing a hydrogenation catalyst in intimate contact by way of impregnation with said coal particles into said thermal cracking zone and catalyst being substantially simulatenously introduced with said coal particles;
- introducing hydrogen into said thermal cracking zone to react with said coal to form a reaction product;
- maintaining said coal and hydrogen in said thermal cracking zone for a time period sufficiently short to yield a reaction product having a ratio of liquid to gaseous hydrocarbon products in excess of 8:1 by weight and a liquid content in excess of 50% of the weight of coal particles introduced into said cracking zone and unrelated coal;
- and
- quenching rapidly the reaction products to a temperature significantly less than 400.degree. C.
A method for converting more than 70% by weight of coal to liquids, while yielding ratios of liquids/hydrocarbon (HC) gases greater than 12/1, by weight, comprising the steps of:
- (a) grinding and screening the coal to fine particles of a size range less than about 65 mesh, Standard Tyler Series;
- (b) applying to said coal particles a catalyst exhibiting hydrogenation/hydrogenolysis activity to obtain high dispersion of the catalyst within the coal particles;
- (c) introducing said coal particles into a reactor hot zone maintained at a temperature between insert 450.degree. C. and about 550.degree. C. and a pressure of at least about 1500 psig, in the presence of a hot hydrogen stream;
- (d) flowing said hydrogen and coal particles through said reactor hot zone at a rate to maintain turbulent flow;
- (e) recycling unreacted coal to said reaction zone;
- and
- (f) controlling the residence time of said hydrogen and coal in said hot zone for a time of less than about 15 seconds.
Dependencies are inferred from the claim text.