DISCUSSION WITH
DR. HOOG OF THE AMSTERDAM
LABORATORY OF ROYAL DUTCH SHELL
The first work on the slurry process was done in a batch-type stirred reactor. This was followed by work in a continuous reactor, 3-inch i.d. and 16 feet long, in which the slurry was circulated from the reactor through a side arm by means of a gear pump. Synthesis gas (1.2H2 to 100) enter at the bottom of the reactor. The gas and lighter products pass overhead to a cooler and then to a gas-liquid operator. Heavy product is removed through a porous filter plate at the bottom of the reactor. The recycle gas is heated electrically before returning to the reactor. The unit was operated at 9 atmospheres (130 psig), 245°C., and 100 SVH (based on volume of slurry) with a precipitated iron catalyst. Several runs of 1000-1200 hours duration were made under the foregoing conditions. In these tests the temperature ranged from 235-265°C., 95% of the CO was converted and the methane formed was low. The usage ratio ranged from 0.7 to 1.1 depending upon the recycle ratio. When attempts were made to increase the pressure the catalyst agglomerated and settled when a pressure of 260-265 psi was reached. In bringing this unit on stream the slurry was heated in an atmosphere of N2 at atmospheric pressure until a temperature of 260-270°C. was reached. Synthesis gas was then fed to the unit for 4 to 24 hours during which time the temperature decreased to 200-230°C. and the pressure was increased gradually maintaining the SVH at 100. The operating temperature was 235-245°C. for about 90% CO conversion.
The development of the slurry process at Shell has been discontinued to give priority to other work. Inexplicable difficulties in the agglomeration and settling of catalyst have been encountered. The Shell technical personnel have neither theories nor explanations to account for their catalyst settling difficulties.