The Norwegian oil and energy adventure is entering a new phase. Most experts agree that the “easy” resources in the region are gone, and producers are seeing declining production and recovery rates. At the same time, the urgency of the climate crisis is creating a demand for cleaner operations. In this increasingly challenging energy world, innovation makes all the difference.
The public sector has increased expectations for the oil and gas industry, with leading voices calling for new, greener energy production technology. “It is crucial that we welcome, promote and contribute to funding research, innovation and implementation of all technologies that contribute to reducing emissions. This requires increased focus on renewable energy such as hydro power, wind power, solar and biomass, as well as energy efficiency. But we must also meet the challenge of reducing the emissions from the production and use of fossil fuels” said Norwegian State Secretary Liv Monica Bargem Stubholt during a speech in Berlin in 2008.
Satisfying the need for greater production and more environmentally friendly operations has been an organizing principle of recent industry technological development. Throughout the sector, innovations in both production and emissions reduction technologies are being put to the test.
Capturing before Harm
Carbon dioxide emissions have long been part and parcel of the extraction and refining process. Industry leader StatoilHydro is taking an innovative approach to controlling these greenhouse gasses at the company’s facility at Mongstad. The firm is building a NOK 615 million CO2 capture and storage plant which is to operate in conjunction with a combined heat and power facility. The site will be equipped with advanced technology that will enable the capture of at least 100,000 tonnes of CO2 per year when it begins operations in 2011. In the second stage of the project, equipment to capture approximately 1.5 million tonnes of CO2 annually will be installed with a target completion date of late in 2014.
This won’t be the company’s first venture into carbon capture. At StatoilHydro’s Sleipner facility, carbon dioxide bi-product gas is captured and stored in bedrock, keeping it out of the atmosphere and reducing its impact on climate change.
||Carbon capture and storage is one important aspect of reducing industry emissions. At Sleipner, StatoilHydro stores carbon dioxide in subsurface geology.
© Alligator film / BUG / StatoilHydro
More Efficient Use of Heat
Mongstad’s carbon capture element is part of series of innovations at the site. Combined Heat and Power (CHP) equipment is also being installed to use the plant’s emissions to generate power.
Output will come from two gas turbines which are linked to both an electricity generator and exhaust fume heat recovery equipment. Power from the plant will be delivered directly to Mongstad and, via the regional grid, to the Troll gas facilities at Kollsnes. The initial energy efficiency of the CHP station is projected to be about 70%, and the company expects that to rise to 80% with further improvements.
Trapping Harmful Vapours
Volatile Organic Compounds (VOCs) are another harmful result of the oil production process, and new technologies are being applied to keep these out of the atmosphere as well. The industry has a major role to play in curbing this component of harmful ground ozone gasses. In 2007, oil and gas production accounted for 39% of national VOC emissions, 90% of which in turn are accounted for by offshore loading.
At Mongstad, StatoilHydro is installing mechanisms to capture the VOCs in oil vapour released when crude oil tankers are loaded. The technology works to purify the gas and pipe it back into the hold as oil components in liquid form.
“Oil vapour capture and recovery is a type of measure that serves well to support StatoilHydro’s environmental ambitions. Mongstad recovers at least 80% of the VOC emissions that were previously released into the air,” according to Terminal Manager Tor Frostestad, quoted on the company’s website.
Recovery is Key
Keeping operations as clean as possible is one side of the coin, but recovery of oil and gas resources remains the key to a healthy business in the sector. Getting more out of the increasingly difficult terrain of the Norwegian Continental Shelf is a top priority for the nation’s oil and gas businesses, and projects are being developed with an eye towards future applications.
The Badger Explorer is a case in point. This disposable rig-less exploration tool for burrowing down to a prospect promises to cut costs while maximizing geological information. The “fly-by-wire” technology is being developed via a Joint Industry Project with Shell, Exxon and StatoilHydro by Badger Explorer AS, headquartered in Stavanger.
In addition to improved recovery, Badger contributes to better environmental performance. On average more than half exploration wells drilled are dry and during construction there are significant releases of mud, contaminated cuttings and other materials. By utilizing Badger, fewer dry wells are constructed, so damaging releases into the environment are reduced.
||The Mongstad facility is being expanded with innovative technology geared towards reducing emissions and increasing energy efficiency.
© Øyvind Hagen / StatoilHydro
Greener Top Drives
NorDrill is a Norway-based company with global offices, specialising in the production of advanced Top Drive machinery. The company points out that their technology is one of the greenest top drives in the world and one of the first to operate on water power.
Nordrill touts the robust quality of its equipment, citing an ability to operate in Arctic conditions at temperatures as low as -40ºC and in desert conditions in heat that reaches +50ºC. And it is relatively compact; the technology is listed as the smallest and most powerful Top Drive available on the market.
Rigs in Service
Another innovative company in the recovery arena is Prosafe AS. The firm’s parent company ranks as the world’s leading owner and operator of semi-submersible accommodation/service rigs, and one of the leading owners and operators of FPSOs, with seven vessels under ownership. In early 2009, three tankers will have been converted to FPSOs, ready to begin production. Innovative turret mooring system designs are a hallmark of the company’s work.
Training for Tomorrow’s Operations
Aker Solutions has taken a major step in developing the skills that personnel will need to operate the innovations being applied in the intervention phase of oil and gas production. Complete testing and training is offered at Aker’s Well Intervention Academy, located at Forus, Stavanger. Designed to recreate realistic offshore conditions as precisely as possible, the Academy also serves Aker Well Service as a testing ground for equipment applications.
Human error is repeatedly cited as the leading cause of HSE incidents in the sector. Aker believes that intensive, realistic training situations create the opportunity to improve employee judgement in critical situations. A wide range of courses are on offer; from introduction to well intervention, to highly technical courses in operation and maintenance of complex tools and services.
Sevan Marine has focused its business on the development of an innovative cylinder-shaped platform type for storage and production of hydrocarbons for both deep and shallow waters. But in addition to applications in drilling units and floating power plants, the firm’s uniquely-shaped hull is being explored for the benefits it may provide for the integration of an LNG containment system.
The Sevan design features the ability to be in full compliance with regulatory demand for environmentally sensitive areas as well. Features include zero discharge with a closed drain system, a waste management system, and low-emission engines.
The Sevan unit can be constructed with a single LNG tank, multiple tanks, or even a combination of LPG and condensate tanks in a single unit. Sloshing tests have been carried out at the Marintek research centre in Trondheim with an eye towards creating sloshing prevention internals for the tank system. Initial results are reportedly encouraging. The company is optimistic about the future of their technology in the emerging market for floating LNG production units.
||Demands for higher production and better environmental performance are driving much of the current research and experimentation in the sector.
© Guri Dahl / StatoilHydro
Looking to Chemistry
Oil sector actors are constantly looking for new ways to improve recovery, and some of the most promising and unusual solutions may come from an unlikely source: bacteria. Scientists have discovered that, by stimulating bacterial growth at an oil/water interface, a substantial reduction in interfacial tension (IFT) results, and this reduction aids in achieving improved oil recovery.
Researchers working for StatoilHydro and SINTEF are experimenting with the injection of microbes in laboratory samples of reservoir sandstone core. The results seem to indicate that, when nutrients are added to stimulate the bacteria, they improve oil production by a process of mobilising the residual oil that is contained in the pore space. Speculation on the cause of this reaction is based on the possibility that the bacteria induce changes in the IFT between the oil and the water, and possibly also because they may alter wetting properties.
Despite the highly difficult process of growing bacterial systems, researchers on this project have cited major progress in by quantitatively monitoring changes in IFT at a simple oil/water interface with use of an advanced laser-light scattering technique.
Strengthening Weak Rock
Another research effort at StatoilHydro is the development of a treatment which acts to chemically bolster weak reservoir rock without impeding oil flow. Weakly consolidated reservoir rocks, which are desirable for their high porosity and permeability, are also frequently problematic because of the tendency for small particles and sand grains to become dislodged and join the flow of water and oil.
These corrosive particles can damage flow lines and other equipment. Currently, there are two primary methods to deal with this challenge: reducing (choking back) the flow rate or the injection of chemicals into the formations to artificially strengthen the rock.
But both these remedies have a downside: they shrink the well’s production capacity. StatoilHydro’s new technique, however, is able to find a better balance, creating enough strength for a friable producing formation to withstand flow-generated forces. By focussing on small, gradual strengthening measures, the visco-elastic binding between sand grains improves without blocking the pore system.
StatoilHydro has successfully applied the treatment to several wells on the Norne field in the Norwegian Sea. One of the fields, on template B, is experiencing an increase of around 12,500 barrels of additional oil per day, compared with the pre-treatment flow. At this rate, the company expects the cost of the treatment will be recouped within hours.
In addition, indications are that operational disruption is minimal because the chemical is pumped directly into the formation during well shut down periods. Production is gradually resumed a mere six hours later. StatoilHydro is currently considering other candidate wells for the treatment.
||Chemical solutions for strengthening weak rock are being explored as a method for improving recovery from fields with difficult conditions.
© Øyvind Hagen / StatoilHydro
Finding Hidden Resources
Before recovery operations can begin, resources have to be located. Qualifying and proving the existence of hydrocarbons, particularly in environmentally sensitive areas, has been a challenge in the past.
New equipment that utilizes Passive Seismic Recording (PSR) allows the geophysical monitoring of potential hydrocarbon-bearing rocks below the sea surface without using environmentally disruptive active wave generators like air guns.
PSR is a technique that has been developed based on listening to the earth’s seismic waves, which are generated by energy, such as by waves hitting the continents. Materials rich in hydrocarbons will send a unique signal to seismometers placed on land or at sea, aiding in location of promising structures. Industry actors are exploring the possibilities of PSR in research projects designed to discover the viability and quality of information the technique can deliver.