Processibility of athabasca oil sand: Interrelationship between oil sand fine solids, process aids, mechanical energy and oil sand age after mining

Processibility curves have shown that strong inorganic bases or anionic surfactants are effective as process aids in the hot water extraction of bitumen from oil sand, but maximum bitumen recovery for each oil sand type is the same for both types of aid. Nonionic surfactants were not useful and there was no general relationship between recovery and surface tension or pH. Bitumen recovery could be correlated with the fine solids component of oil sand. The amount of NaOH required to reach maximum recovery and the rate of aging of oil sand were also functions of the fine solids content. Shear during slurrying was also found to be important, and it was shown that, without a certain amount of mechanical energy, good bitumen recovery could not be achieved, regardless of how much process aid was used. A theory of processibility is proposed to explain the interactions among process aids, mechanical energy, oil sand fines, and age of oil sand after mining.