Further developments in coal hydrogenation since

Renewed efforts to improve coal liquefaction by hydrogenation and extraction, particularly in the early 1970 s, were aimed at overcoming these difficulties and obtaining the highest possible oil yields at relatively low pressures and reasonable hydrogen consumption. 

The SRC (solvent refined coal) process of Pittsburgh Midway Coal Mining Gulf Oil) is an advanced version of the Pott-Broche extraction process. The purpose of the SRC method is to desulfurize coal to yield a solid, low-sulfur fuel. 

In the SRC process, the crushed coal is mixed with process-derived oil to pro- 

The process operates without catalysts, since the catalytic activity of the finely divided pyrites in the coal feedstock is sufficient. Hydrogen consumption is around 2%. The undissolved residue is separated by pressure filtration. A pilot plant was started up at Fort Louis in Tacoma/Wash., USA in 1974, with a throughput of 50 t/d of coal. By increasing the severity of cracking, this method can also be used to produce heavy heating oil (SRC-II process). 

1 Coal-slurry production 2 Tubular furnace 3 Hydrogenation reactor 4 Gas separator  

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