Direct coal liquefaction process

Abstract

A direct coal liquefaction method and apparatus in which the feed coal is mixed with a recycled 600° F.+ non-donor stream in which the ratio of coal to said stream is at least 1.5:1 on a moisture free basis to form an input slurry to a DCL reactor. Hydrogen containing treat gas is supplied to the reactor. 1000° F.− bottoms from the reactor are recycled as part of the 600° F.+ non-donor stream. 1000° F.+ bottoms from the reactor are gasified in a PDX unit to provide hydrogen for the DCL reaction. The ratio of recycled bottoms to feed coal is between 1:0.5 and 1:1.5.

1 ) A method for producing liquids from feed coal, comprising the steps of:
 a) mixing a feed coal having an greater than 12% inertinite content with a non-donor stream that includes a recycled 600° F.+ fraction of the product from a direct coal liquefaction (DCL) slurry reactor to form a feed coal slurry, the ratio of non-donor stream to feed coal being greater than 1.6:1 on a moisture free basis;   b) supplying said feed coal slurry to said DCL slurry reactor;   c) adding a molybdenum or iron containing microcatalyst to the input of the DCL reactor; and   d) supplying H2 containing treat gas to the DCL reactor.   
     
     
         2 ) The method of  claim 1  wherein said microcatalyst consists essentially of molybdenum. 
     
     
         3 ) The method of  claim 2  wherein the concentration of the microcatalyst added during steady-state operation of the DCL reactor is equivalent to 100 to 300 wppm relative to the feed coal on a moisture and ash free (MAF) basis. 
     
     
         4 ) The method of  claim 1  wherein the ratio of said non-donor stream to feed coal is at least 1.7:1. 
     
     
         5 ) The method of  claim 1  wherein the ratio of said non-donor stream to feed coal is between 1.8:1 and 3.5:1. 
     
     
         6 ) The method of  claim 1  wherein the ratio of said non-donor stream to feed coal is between 2.0:1 and 3.0:1 
     
     
         7 ) The method of  claim 1  wherein said non-donor stream includes a portion of the 1000° F.+ fraction of the DCL product. 
     
     
         8 ) The method of  claim 1  wherein the DCL reactor includes a plurality of series connected slurry liquefaction reactors. 
     
     
         9 ) (canceled) 
     
     
         10 ) The method of  claim 1  wherein said feed coal and said non-donor stream are mixed in a slurry mix tank and the temperature of the slurry in said slurry mix tank is between 300 and 600° F. 
     
     
         11 ) The method of  claim 10  wherein the temperature of said slurry in said slurry mix tank is between 300 and 500° F. 
     
     
         12 ) (canceled) 
     
     
         13 ) The method of  claim 2  wherein said molybdenum microcatalyst is added at a rate between 100 and 1,000 ppm by weight with respect to the coal feed on an MAF basis. 
     
     
         14 ) The method of  claim 2  to wherein said molybdenum microcatalyst is added at a rate between 100 and 500 ppm by weight with respect to the coal feed on an MAF basis during steady-state operation. 
     
     
         15 ) method of  claim 1  where the ash content of the coal is between 6 and 20 wt % on the moisture free basis. 
     
     
         16 ) (canceled) 
     
     
         17 ) The method of  claim 1  wherein the inertinite content of the coal is greater than 25%. 
     
     
         18 ) The method of  claim 1  where hydrogen for liquefaction and upgrading is produced in a Steam Methane Reformer or an Autothermal Reformer and 1000° F.+ fraction from DCl reactor is used for power generation, steam generation, or sold. 
     
     
         19 ) The method of  claim 1  wherein the ratio of treat gas to slurry supplied to the DCL reactor is less than 900 NL/kg of slurry.