Industry probes abyssal depths, hydrate caps; land depletion pushes other industries offshore
The deep oceans are the last frontier on earth, and a reservoir of unknown resource potential.
The offshore hydrocarbons industry in the year 2047 could be largely unrecognizable, if the past 50 years is any indication. Also, other resource industries may be operating offshore by then - capturing products that are not now economic or lack commercial markets.
At the present, the hydrocarbons industry is virtually the only commercial business in deepwater, and may operate for decades alone if abyssal sedimentary sections prove productive. But the industry will change drastically to meet greater technical and economic hurdles.
What will the offshore hydrocarbon business look like in 2047? What areas of technology and business are most likely to change? The following are probabilities based on current trends and ongoing research and development in the hydrocarbon as well as other prospective industries:
- Minimal surface facilities: Reduction of the physical size of production facilities will continue through the next decade, along with manning requirements. Investment requirements will remain high because much of the surface gear will move subsea. Size reduction of mobile drilling units will take much longer because deepwater capabilities still require stability and storage. On the drilling end, continuous string drillpipe injection, either at the wellhead or surface, and re-circulation of drilling fluids at the seabed eventually should halve the size of surface facilities. On the production side, seabed facilities to separate gas and water at the seabed and inject them downhole will shorten separation cycles. A deep hull spar may be the ideal production vessel in the future.
- Riser elimination: Handling borehole and tubing flows at the seabed instead of the surface for both drilling and production operations should remove the need for a large riser, reducing the size and mooring demands at the surface. Cuttings removal, fluid additives, and chemical injection to solve hydrate and paraffin problems will be routed through separate umbilicals.
- Two-tier drilling system: Initially, a two tier system will emerge: sectioned drill pipe for vertical hole; reeled pipe for all laterals. Coiled tubing drilling, hydraulic rigs, and slimhole operations are laying the groundwork for the advent of reeled drillpipe. With more lateral hole, weight on bit is less important. Much will depend on the development of tougher reeled pipe and the ability to replace worn sections in the field.
- Expandable liners, casing: Expandable liners and casing, made from chemically cured composites or thin-wall tough steel, will provide a single bore diameter from top hole to completion interval. Steel walls can be expanded with pigs. In addition, the casing and liner strings can be pulled off a reel. With thinner walls, cement jobs must be top quality.
- Fewer development wells: Multi-lateral and extended reach drilling technologies are still in their infancy. The industry is investigating new methods of pushing the drill bit laterally and stabilizing lateral boreholes. More lateral footage could mean less vertical footage, but total footage may remain high for decades to come if oil demand remains high.
- Selective access: The demand for lateral footage and rising drilling costs is likely to push up development of multiple completions for each borehole with a high degree of selectivity. Radial placement in the casing of as many as four production strings and sleeved completions in multiple lateral boreholes will allow selective production access and possibly injection in virtually any part of the reservoir. Also, the machinery to cut windows or sections and to selectively change producing intervals will range far ahead of the rough methods in use today.
- Subsea communications: Radio frequency and acoustic transmission of audio and video signals underwater operate poorly with water depth. Batch transmission of acoustic signals combined with modest artificial intelligence at the seabed level could solve some problems in the mid-term, but a real solution may depend on putting a manned vehicle with manipulators down in very deep water or the use of presently classified technologies used by military submarines to communicate underwater.
- Gas-to-liquids technologies: Inexpensive and small scale methods of converting natural gas into middle distillates are underway now (see lead story in this issue) and should be even more economic and flexible by the year 2010. This technology will move remote gas fields into production quickly and reduce the need for pipelines and LNG operations, while eliminating flaring for all but the most temporary operations.
- Seismic definition: Dry holes occurrence will drop to nearly zero in the decades to come because geophysicists will continue to mine seismic and acoustic data for more geological, maturation, and reservoir content information. Fifty years from now, acoustic physics will probably be able to determine the exact chemical signatures of reservoir contents.
- Methane recovery: Methane, derived either from beneath hydrate caps or gasification of hydrate pads, may be captured in future years. Much would depend on the ability to attach production equipment to the hydrate pads and convert the gas to liquids at the surface, but the global resources are huge.
At the present, virtually all innovation in deepwater operations evolves from oil and gas recovery operations. But that could change with economics in the coming decades and other innovative industries will emerge.
- Ocean mining: Deepwater ocean mining equipment development has been underway in a limited fashion for some years, primarily in Japan. The equipment is selectively ready, but the economics will not support commercial mining for at least two more decades. When land mineral recovery is no longer as inexpensive as it is today, offshore mining will begin.
- Seafloor vent mineral extraction: Seafloor vents feature super-heated water and, for that reason, contain heavy concentrations of dissolved and particle minerals from volcanic and tectonic deposits. A mining process would involve dealing with the super-heated water at the vents and moving the entire flow or extracted minerals through long umbilicals to the surface.
- Seawater mineral extraction: Mineral extraction from seawater, unlike vent mineral recovery, is not as lucrative and would involve a low-cost, high volume procedure. The technology is available but the process will remain undeveloped until land mineral extraction for such products as gold, magnesium, and cobalt becomes much less economic.
- Pharmaceuticals: Research in this area has been marginal, however, the combination of huge deepwater pressures and chemistry at abyssal depths may present some interesting industrial possibilities in the decades to come. Anaerobic organisms that grow in high temperature, high pressure conditions and consume hydrocarbons for food have interested scientists for years and may have pharmaceutical or environmental remediation value.
The deep oceans are the last frontier on earth. Scientific researchers have a modest understanding of seafloor topography, subsea plate tectonics, currents, and biological life in the deep oceans, but knowledge is sparse compared with land exploration. Marine exploration is confined necessarily to a vertical slice of water column and seafloor.
Until there is an economic need, wide exploration may be confined to multi-country research programs (Ocean Drilling Program, etc.) or separate research conducted by military groups for strategic advantage
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