"Facilities and Construction Engineering". Petroleum Engineering Handbook vol. 3

Facilities engineering is a broad specialty embracing all of the classic engineering specialties such as civil, chemical, mechanical, and instrument/electrical, as well as the broad science of project management. Authors have attempted to provide the non-facilities engineer with a basic understanding of the equipment and systems we use, how they work, the relative advantages and disadvantages that aid in choosing between alternatives for a specific set of conditions, and a better understanding of the terminology so that those with a general knowledge can interface more effectively with experts in each of the different subspecialties.

The science of facilities engineering did not exist in the early days of oil and gas development. Oil was produced to tanks, where gas was vented and water and sediments were allowed to settle to the bottom. In the early 1900s, anecdotal evidence indicated that oil recovery was higher when a separator preceded the tank than when oil flowed directly into the tank. The original separators had working pressures of approximately 150 psi with simple mechanical lever-operated controls. With time, as deeper, higher-pressure wells were drilled and local distribution systems were developed to use the gas, separator working pressures increased. It was not until the mid-20th century that horizontal separators were first developed and tested to handle a growing need for high gas flow/low liquid flow separators. At this point, facilities were not designed in a systematic way. For the most part, field personnel using empirically developed rules of thumb were able to “hook up” standard components based on slowly evolving experience with little or no disciplined thought. The need for documentation, quality control, and modern sensitivities to safety and environmental concerns were only beginning to be formed. Since the 1950s, facilities have become more complex and more important for the overall economics of field-development decisions. The science of facilities engineering was born as the need and markets developed for heavy oil, waterflooding, sour oil and gas, high-pressure gas, and remote, offshore, and Arctic fields. Beginning in the late 1950s, oil companies began to recognize the need to hire, train, and employ facilities engineers as a distinct specialty. The main objectives of a surface facility are to (1) separate the gas, oil, and water produced from the well; (2) process and treat the gas for sales, reinjection, or flaring; (3) treat the oil for sales; (4) treat the water for reinjection or disposal; (5) provide for well testing. Besides performing these process tasks, a facility must provide (1) utilities (electric power generation and motor control center, instrument and power air, diesel fuel system, and helicopter fuel); (2) safety systems (process shutdown, fire and gas detection, fire fighting, escape and evacuation, and emergency gas disposal); (3) life support (quarters and recreation, potable water system, sanitary systems, food storage, and medical facilities); (4) operating and maintenance systems (cranes and lifting equipment, office, control room, spare-parts storage, and laboratory), and, of course, a foundation for all the equipment (e.g., site development, access, offshore platform).