Page 422 - Compression Machinery for Oil and Gas

Chapter 10

Downstream

†
Grant Musgrove*, Cyrus Meher-Homji and Dave Moss ‡
* †
Southwest Research Institute, San Antonio, TX, United States, Bechtel, Houston, TX,
‡
United States, UE Compression, Henderson, CO, United States

Introduction
Downstream applications in the oil and gas industry refer to the refining of
hydrocarbons into more valuable products or the use of those products. Com-
pressors are directly used in the refining process such as in the production of
liquefied natural gas (LNG). However, compressors are also used to support
refining processes, such as hydrogen compressors that supply hydrogen feed-
stock for the refining process. Additionally, compressors can be used with
the final product, such as a fuel gas compressor that provides the high pressure
required for a fuel to be used in a gas turbine engine. This chapter provides an
introduction to the types of compressors and how they are used in downstream
oil and gas applications, notable LNG production, refining applications, and
fuel gas compression (FGC).

Refinery Applications
Worrell and Galitsky [1] note that compressors consume about 12% of total
electricity used in refineries. Of the 12%, the major applications are compres-
sors providing air for furnace combustion and compressing gas streams in the
refinery. The majority of refinery compressors are used for process gas recycle,
process air, exhaust gas, hydrogen, flare gas, and wet gas compression. Wet gas
compression refers to the use of a fluid catalytic cracking (FCC) compressor in
which the process gas contains condensable hydrocarbons, such as butane and
propane. Refinery compressors are typically a centrifugal-type, but can be a
positive-displacement-type for low mole weight gases, such as hydrogen. Bloch
[2] notes that many compressors are used in a refinery process; “A typical mod-
ern refinery processing more than 400,000 BPD (barrels per day) of crude oil
may have 25 centrifugal compressors with polytropic heads in the range of
6100–22,860m, average impeller tip speeds of perhaps 230–320m/s, pressures

Compression Machinery for Oil and Gas. https://doi.org/10.1016/B978-0-12-814683-5.00010-9
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