Page 56 - Handbook of Natural Gas Transmission and Processing Principles and Practices

FIGURE 1.10 Technologies available to transport natural gas to long distances (Wood and Mokhatab,
2008).

For onshore and near-shore gas, pipeline is an economical option for transporting natural gas to
the consumers. However, as transportation distance increases, particularly in offshore and
deepwater exploration, development of these projects is challenging and expensive, and requires a
large diameter long distant pipe network. They require both large, high-value markets and
substantial proven reserves to be economically viable. On the other hand, gas processing
technology has advanced significantly in the past two decades, overcoming challenges of upstream
gas conditioning, hydrate control, and subsea pipeline design that makes the gas-transportation
economical. Raw (unprocessed) gas transmission by means of pipelines is discussed in detail in
Chapter 3.
Intercontinental pipelines usually entail the crossing of several countries and borders, which
means that several governments may have jurisdiction over the pipelines, increasing the complexity
of the projects. There are many challenges such as unexpected gas supply interruptions, terrorist
attack on infrastructure, or pipeline shutdown during political turmoil.

1.10.2. Liquefied Natural Gas

Liquefied natural gas (LNG) technology has been proven to be effective over the last 50 years.
When natural gas is cooled to approximately −260°F (−162°C) at atmospheric pressure, a condensed
liquid forms which is termed liquefied natural gas (LNG). The volume reduction is about 1/600th
the volume of natural gas at the burner tip. The physical properties of LNG allow for its long-
distance transport by ship across oceans to markets and for its local distribution via regasification or
by truck transport. Occasionally, liquefaction of natural gas provides the opportunity to store the
fuel for use during high consumption periods, as well as in areas where geologic conditions are not
suitable for underground gas storage facilities.
The much lower volume of liquefied natural gas (LNG) relative to gaseous natural gas can reduce
transportation costs by allowing delivery using cargo ships or transport trucks instead of pipelines.
However, the costs of building a liquefied natural gas plant are higher than other project options for
a number of reasons, including high energy consumption, use of expensive cryogenic materials,

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