What are the pros and cons of using heavy oil produced from oil shale?: What are the pros and cons of using heavy oil produced from oil shale?
Oil Shale–fine grained rock that contains a solid, waxy mixture of hydrocarbon compounds called kerogen. After being removed by surface mining, the shale is heated above ground in a retort to vaporize the kerogen. Shale oil–heavy, slow forming, dark brown material formed by condensing the kerogen vapor. Problems with shale oil: Problems with shale oil It has a lower net energy yield than does conventional oil because it takes the energy from almost half a barrel of conventional oil to extract, process, and upgrade one barrel of shale oil. Processing the oil requires large amounts of water, which is scarce in the semiarid locales where the richest deposits are located. Surface mining of shale oil tears up the land, leaving mountains of shale rock (which expands when heated). Salts, cancer causing substances, and toxic metal compounds can be leached from the processed shale rock into water supplies. Some of these problems can be reduced by extracting shale oil underground, but this met
