Natural Gas

Natural gas is a fossil fuel that formed when layers of buried plants, gases, and animals were exposed to intense heat and pressure over thousands of years. The energy that the plants originally obtained from the sun is stored in the form of chemical bonds in natural gas. Natural gas obtained from underground is a nonrenewable resource because it cannot be replenished in the human time frame [1-10]. Natural gas is colorless, shapeless, and odorless in its pure form, and when burned, it gives off a great deal of energy with fewer emissions than many other sources. Compared to other fossil fuels, natural gas burns cleaner and emits lower levels of potentially harmful by-products into the air. Natural gas is a combustible mixture of hydrocarbon gases. While natural gas is composed primarily of methane, it can also include ethane, propane, butane, and pentane. The composition of natural gas can vary widely; Table 2.1 [2,10] illustrates the typical makeup of natural gas before it is rened.