ABSTRACT
Gas processing (Mokhatab et al., 2006) consists of separating all of the various hydrocarbons
and fluids from pure natural gas (Figure 25.1). Major transportation pipelines usually impose
restrictions on the makeup of the natural gas that is allowed into the pipeline. That means
that before the natural gas can be transported it must be purified. While the ethane, propane,
butane, and pentanes must be removed from natural gas, this does not mean that they are all
waste products. Gas processing is necessary to ensure that the natural gas intended for use is
as clean and pure as possible, making it the clean burning and environmentally sound energy
choice. Thus, natural gas, as it is used by consumers, is much different from the natural gas
that is brought from underground up to the wellhead. Although the processing of natural
gas is in many respects less complicated than the processing and refining of crude oil, it is
equally as necessary before its use by end users. The natural gas used by consumers is
composed almost entirely of methane. However, natural gas found at the wellhead, although
still composed primarily of methane, is by no means as pure.