Page 55 - Handbook of Natural Gas Transmission and Processing Principles and Practices

1.10. Natural Gas Transportation
Transportation is an essential aspect of the gas business, since gas reserves are often quite distant
from their main markets. For almost a century, natural gas has been transported safely, reliably, and
economically via pipelines that are used to bring the gas supply from various production wells to
the metropolis. Pipeline system has been providing the stability and long-term security by
balancing the supply and demand markets. Now, in the 21st century, the vast majority of the large,
conventional natural gas reserves have been already tapped, and attention is shifting to stranded
reservoirs that were previously thought too small, too remote, or technically too difficult to
develop. The liquefied natural gas (LNG) industry has commercialized many large remote gas
fields over the past three decades and developed gas markets commercially unreachable by
pipeline.
Over the last two decades, several technologies have been also evaluated and proposed for
monetizing hitherto remote gas reserves (see Fig. 1.10). These include: a number of technologies
converting natural gas into a range of easily transported and marketed hydrocarbons (grouped
under the generic term “gas-to-liquids” or GTL technologies); using gas to produce electricity at the
production field and then transporting it by high voltage direct current (HVDC) transmission lines
to long distances (generically referred to as “gas-to-wire” technologies); compressed natural gas
(CNG) that avoids the cost of gas liquefaction; converting gas, particularly associated gas, into
solids or slurries formed of gas hydrates for storage and transportation (generically referred to as
“gas-to-solids” technologies). The latter two technologies are still in the research and development
stage and, although much work has been done to verify the potential of these options in the past
decade, no commercial projects exploiting them have yet been sanctioned (Mokhatab and Wood,
2007).
The following section examines some of these technical methods by which natural gas energy can
be converted and transported to the consumers.

1.10.1. Pipelines

Pipeline transportation has been employed to deliver gas to markets for a long time. However,
supply of natural gas to markets via gas pipelines is often faced with technical, economic, and
political uncertainties.
Pipelines are a very convenient method of transport but often have limited flexibility. If a pipeline
must be shut down, downstream facilities will be shut down. The downstream facilities can
continue to operate until the inventory in the gas lines is depleted.

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