The coal-based diesel process mainly includes three subprocesses: CG (coal gasification), FTS (Fischer-Tropsch synthesis), and OH (oil hydrocracking). First, raw coal is ground together with water and additives in a mill to form a slurry. Once the required particle size distribution is achieved, the coal slurry from the slurry preparation system is fed into the gasifier together with oxygen from the air separation unit to produce raw synthetic gas. The raw synthetic gas is cooled by direct contact with water and then cleaned in a venturi scrubber and scrubbing tower. Subsequently, the cooled and cleaned synthetic gas is fed into the WGS (water-gas shift) reactor to produce sufficient amounts of H2. The Rectisol (cold methanol wash) process is selected to remove CO2 and H2S from shifted synthetic gas in the AGR (acid gas removal) unit. The cleaned synthetic gas is then fed into a slurry-bed reactor for synthetic oil production. The oil is sent to a hydrocracking reactor to initiate the hydrocracking reaction. The bottom product from the hydrocracking reactor is fractionated in a distillation column to produce diesel and petrol.