SULFUR CAPTURE DURING GASIFICATION OF OIL SAND COKES

The capture of sulphur via the H2S-CaO reaction during gasification of delayed coke has been investigated in a 6.4 cm dia. semi-batch stirre d bed reactor. Calcines from one of three limestones or a dolomite wer e mixed with coke which was then gasified in a steam-nitrogen mixture at atmospheric pressure and 930-degrees-C. The H2S content of the gas, and the sulphur content of the sorbent were determined as functions o f time. The effects of sorbent surface area, percentage calcination, a nd the Ca/S ratio on the extent of sulphur capture and the conversion of sorbents were determined. The sulphidation reaction was analyzed us ing continuous and grain models. After an initial stage of chemical co ntrol the reaction appears to be controlled by diffusion through the p roduct layer of the grain.