Heavy media separation of SRC-II feedstocks: 2. Effect on liquefaction yields

The objective of this investigation was to assess the potential effects of coal preparation on SRC-II liquefaction yields. Liquefaction yields were estimated from coal properties at standard SRC-II conditions using mathematical models. For Powhatan and Ireland Mine coals, the yields were most sensitive to changes in the total sulphur level and were not significantly affected by the small changes in total reactive macerals, H/C ratio or volatile matter. The fractions from both coals were ranked in order of decreasing liquid yields (or increasing organic vacuum bottoms yields) on a dry, ash-free basis as follows: middling > cleaned > ROM (run-of-mine) > deep cleaned. On a dry basis, all the washed fractions from each coal were superior to the ROM coal, giving higher liquid yields.