Introduction to Oil and Gas Production

Transcription

1 Introduction to Oil and Gas Production Steven Marzuola ATA Energy Conference May 4-6, 2007 Houston Texas Introduction Dope, Joints, Tripping Strippers Casing, Tubing, Liner API - American Petroleum Institute Life of an Oilfield Reservoir formation Discovery and exploration Drilling Production, well intervention Abandonment 3 Early oil discoveries Usually guided by surface seepage. Lake Maracaibo was destination for ships, seeking tar for repairs. Oil was usually a nuisance encountered when drilling water wells Research in mid 1800 s, search to replace whale oil used in lamps First rotary drilled well , Titusville, PA 4 Blowouts Historical practices On land, in the USA: Surface owner owns everything to the center of the earth. Often led to inefficiencies, legal battles. Today, mineral rights on most property are bought and sold separately from the surface land. Field or reservoir usually managed as a single unit. 5 6

2 Congestion Requirements of a Reservoir 1. Source or Generator rock 2. Reservoir 3. Seal or cap rock 4. Structure, hydrocarbons trap 5. Timing 6. Maturation 7. Migration 7 8 Exploration aided by geology Anticlines Salt dome Surface features Anticlines Faults, Salt domes Presence of iron Subsurface surveys Gravimeter, Magnetometer Seismic- 2D, 3D 9 10 Structural trap Gravimeter 11 12

3 Seismic surveying 3D Seismic images Today s drilling Most wells drilled using rotary drilling Steel drill pipe comes in 30-foot sections that are threaded on both ends. Each section of drill pipe is called a joint. After drilling 30 feet, the kelly must be raised and another joint of pipe added below the kelly. This is called making a connection Drill string components Drill bits Typical rotary drilling Bottom Hole Assembly (BHA) Additional components: mud motors, LWD / MWD tools, steerable subs Diamond bits Tricone rock bit - jets, teeth. Some use tungsten carbide teeth 17 18

4 Surface components Pipehandling tools Kelly, kelly bushing, swivel, hose 19 Drill pipe slips Tongs 20 Pressure control Flow of drilling mud Hydrostatic pressure Mud system components Pressure is proportional to: Height (depth) of fluid column Density (i.e. lbs/gallon) Water (8.34 lb/gal) provides a pressure gradient of psi/ft 10,000 ft well full of water; bottom hole pressure = 4333 psi Drilling mud usually weighs times more than water Shale shakers Desanders and desilters (hydrocyclones) Degassers Centrifuges Mud agitators Cuttings washers 23 24

5 Water-based vs. oil-based muds Modern improvements Water most widely used, but can cause skin damage, contaminate formation In response, oil-based muds were developed Adverse effects on rubber products, (seals, pump parts), environmental concern Major changes in past 20 years are: 3D seismic, software, computer Top drive - all offshore rigs, big/deep onshore MWD - Measure While Drilling technology Mud motors Directional drilling => horizontal wells Horizontal drilling Top Drive Multilateral completions Completions Most wells lined with steel casing. Purposes: Protect from cave-ins Protect surface formations, water supply Isolate producing formations Prevent blowouts Innermost pipe is tubing, removable, to isolate flow from casing 29 30

6 Casing and wellhead Wellheads/Christmas trees Separation equipment Stages of production Primary recovery - natural flow Secondary recovery - mechanical pumping, gas lift Tertiary or Enhanced Oil Recovery - Gas injection, thermal, chemical Workover and well servicing Flexible tubing rig Together known as intervention Workover rig similar to drilling. Performs acidizing, fracturing stimulation, cementing, deeper drilling, recompletion to a different zone, sidetracking Well servicing - wireline, rod pulling units, flexible tubing 35 36

7 Steven Marzuola Typical Rod Pump Pumping 37 Other methods 38 Offshore - Everything is BIG FPSO - Floating Production Storage, Offtake Norske Shell Troll A Water depth 303 meters Overall height 472 meters Weighs 656,000 tons. Produces gas from 40 wells Towed 200 km to the Norwegian Sea. Tallest structure ever moved by man

8 ChevronTexaco Genesis Chevron Typhoon meets Rita Peak Oil, or Hubbert s Peak M. King Hubbert - Shell geophysicist Theory: production tends to follow bell-shaped curve. Can be predicted in advance. Production increases early due to discoveries and new infrastructure. Later declines due to depletion. Peak Oil, or Hubbert s Peak (cont) In 1956, Hubbert predicted peak of USA production late 1960s - early 1970s. Controversial, but proven right by Actual peak was in Is it applicable to world production? Rapidly growing demand in China, India New technologies Historical oil production Steven Marzuola steven@techlanguage.com 47 48