Mineral oils extraction from rock

Which is extracted from air by any means, shall automatically be included in the Inventory under the category Naturally Occurring Substances. Examples of such substances are raw agricultural commodities water, air, natural gas, and crude oil and rocks, ores, and minerals. 

A major problem in the treatment of nonaqueous systems is the removal of eolloidal particles to produce acceptable liquid products (e.g., fuel oil). Such a situation is encountered in hydrocarbon production from tar sands and oil shale. The particles (such as oxides, silicates, and clay mineral) suspended in the hydrocarbon hquids originate from a rock matrix. Particle separation problems occur in the solvent extraction of bitumen with nonaqueous media such as toluene. Electrostatic forces (bonding forces) play a predominant role in the physical state of these nonaqueous systems. In many instances, by addition of antisolvents, and selecting the proper temperature and agitation, these systems can be altered to improve solid separation. Separation of carbon black particles suspended in tetralin using Aerosol OT as a surfactant and by filtration through a bed of sand (deep-bed filtration) is another example of liquid-solids separation in nonaqueous systems. 

Desired minerals are always mixed with other rocks that must be separated. In many cases, particularly for more valuable metals, the mineral that is sought is less than 1% of the ore. This requires processing of the ore, a procedure called beneficiation, which produces relatively large amounts of finely divided by-product rock. For economic reasons, beneficiation is usually carried out at the mine site with the residues returned to the mine or left in piles at the site. As a result, water pollution problems may develop from the leaching of mine spoils. Some communities in the vicinity of lead mines have been contaminated by lead from mine residues, with particular concern over the health of exposed children. Spoils from iron mining in Minnesota have contaminated water with an asbestos-like mineral associated with the iron ore, requiring remedial action that has cost millions of dollars. Enormous piles of tar-contaminated sand are left over from the extraction by hot water of heavy crude oil from tar sands in the Canadian province of Alberta. 

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