Subject:- Applied Chemistry 2.

Topic:- Fuels

Difficulty:- High

Petroleum is found underneath the earth’s surface at different depths (at about 5000 feet or more) varying from place to place. The oil is found below the impervious rocks floating over the salt water of brine. It is often accompanied by natural gas (mainly methane) which exerts pressure on oil surface and drive out oil through natural openings but when the pressure is low, the oil has to be removed by the air lift pump. Mining of oil is done by drilling holes in the earth’s crust and sinking two coaxial pipes into the oil bearing strata.The compressed air is forced through the outer pipe when oil comes out through inner pipe.