Despite the challenges, technology has evolved and revolutionized the exploration and expansion of current and new oil fields, especially the deep water well construction
Over the last decade, there has been a shift in the structure of the oil and gas industry, which has had a huge effect on the nature of innovation and on how research and development (R&D) is carried out within the industry. Many industry observers will acknowledge that oil companies, the ultimate customers for the whole oil and gas supply chain, are becoming increasingly focused on cost savings.
The new technology reduces drilling costs and increases the productivity since it helps expanding the supply of oil that can ultimately be pulled out of the ground. Nevertheless, skeptics argue that recent advances are only helping the industry pull oil out of the ground faster, and that the overall pace of discovery hasn’t picked up. However, for the past decade, the oil industry has invested on 3D computing technology to extend its reach and find more oil.
One misplaced well costs a lot of money in vain, while another well which decided not to be drilled saves money that then can be put toward one that is more economic by using modern technology. With oil prices hitting new highs, proponents of so-called “peak oil” argue that the world may be approaching the point where production cannot keep up with demand. And innovations, like 3D, are at the center of a debate over whether technology can help replace the world’s known oil supplies before they are depleted.
For instance, advances in drilling techniques do hold the promise of further lowering the cost of producing new oil and extending the industry’s reach. That’s especially true in deepwater offshore fields where many promising discoveries are turning up. For the reason that huge volumes of the world’s future oil reserves lie in deep waters at the very limit of our current reach, and just beyond. Moreover, by all indications, tomorrow’s drilling will be even deeper. The rapid advances in deepwater exploration and production (E&P) methods over the past five years ensure that as soon as one deepwater record is broken, another surpasses it. Some estimates suggest that 90% of the world’s undiscovered offshore hydrocarbon reserves hide in water depth greater than 1000m.
There are multiple definitions of “deep” water, which vary depending on the activity being considered. By and large, for well construction, 1500ft, or 500m, is considered deep. Deeper than that, the technology requirements change, but solutions are available. And deeper than 7000ft, or 2000m, is ultra deep water.
The greatest challenges in constructing wells in deep water are related somewhat to the great depth, but also to the conditions encountered in each deepwater oil province. In the deepest waters, drilling can be accomplished only from dynamically positioned semisubmersible rigs or drill ships. While the primary challenge facing deepwater well construction is to drill a stable hole. Drilling a hydraulically stable hole can be achieved only by keeping drilling mud weight within the margin between fracture and pore-pressure gradient. The current water depth record in drilling for hydrocarbons is held by a Petrobras well in 9111ft, or 2780m, of water offshore Brazil.
In the deepest waters, today’s wells are completed with wellheads and production trees on the seafloor that connect to flowlines for transporting hydrocarbons to surface. The wells may be made more productive by implanting permanent monitoring and flow-control devices down-hole. Keeping fluids flowing at the highest possible rates requires not only adequate tubing size, but also attention to conditions that can lead to other flow blockages. At the high pressures and low temperatures that deepwater wells encounter near seabed, solid, ice-like compounds called gas hydrates can form from mixtures of water and natural gas. These solids can block flow in tubular, and depressurize explosively when brought to surface. They have been responsible for offshore drilling catastrophes in the past. Hydrates can also form naturally at and below the seabed, creating a drilling hazard if penetrated.
In order to ensure cost-effective, safe and efficient operations in deep waters, the industry must develop solutions to these problems. In some cases, the solutions will be a new tool or completely new technique; however, in others an innovative application of existing technology will provide the solutions.
Deepwater operations vary significantly compared to conventional operations in shallow waters, drillers obviously encounter different environmental conditions, challenging drilling and exploration processes as well, but once successful the results can be very lucrative, particularly in the long-run. The proliferation of deepwater development projects will likely continue to grow, as long as the technology and financial incentives make the ventures increasingly profitable.
By Ahmed Morsy