Decom North Sea Article: Andrew Louden Q&A
isol8 was recently created to service the decom market; why now?
In truth, isol8 wasn’t created to service the well decommissioning market specifically. Our primary focus is the development of bonded-alloy barriers for wellbore ‘isol8tion’ applications. We spent considerable time engaging with clients, highlighting the benefits of alloys compared with elastomers as a sealing mechanism for downhole applications. The plug and abandonment (P&A) market application attracted the greatest client interest. Decom is a live topic for many North Sea operators who face significant financial decommissioning liabilities so there is an appetite to invest in new barrier materials that address the high costs associated with the use of cement as a permanent abandonment seal.
What technical challenges are you experiencing?
The old North Sea wells pose many operational challenges. The ultimate P&A goal is to develop a method for creating a rock to rock barrier envelope that doesn’t require extensive drilling-rig operations – i.e. rigless. Isolating one or more annuli without the need to recover completion tubulars is the biggest technical challenge for ‘eternal’ P&A barriers. The UK Oil and Gas guidelines for the qualification of alternative materials defines ‘eternal’ as 1 million days. Achieving a positive pressure test on any well barrier can be difficult but the targeted barrier life expectancy of 1 million days raises the bar to a completely new level; far beyond current best practice cement barriers. isol8 has embraced a rigorous scientific approach to barrier design. We have deployed complex computational fluid dynamic modelling to understand the fluid behaviour and thermal losses in order to establish the technical limits. This has led us to perform even more elaborate multi-physics modelling to very accurately predict phase change behaviour of the wellbore fluids and alloy during the exothermic barrier setting process. Understanding the technical limits has been instrumental in the design of our Fusion P&A barrier product. We flow thermite through perforations into the annulus to generate sufficient radial heat to form an impermeable bonded-alloy barrier.
What differentiates your technology?
We performed a range of tests on different alloys before engineering the optimum barrier material. Our metallurgically bonded-alloy creates a new standard in zero emission wellbore isolation products. The alloy system that we have developed can be used in downhole wellbore temperatures of 120°C or more and has significant advantages over expanding bismuth alloys. Our test results revealed that the shear-bond strength of isol8’s bonded alloy is 8 times greater than that of unbonded bismuth alloy.
Does isol8’s technology contribute towards OGA’s 35% cost reduction target?
The OGA has estimated that 44% of UK North Sea decommissioning costs will be attributed to well abandonment activities. The UK P&A activity is currently forecast to cost £22Bn. The most significant time and cost element associated with this relates to the recovery of completion tubulars and the deployment of drill-pipe to clean and prepare the well for setting cement plugs. These activities represent 50%-70% of the costs. isol8’s bonded-alloy, multi-annulus barrier technology can be deployed on slickline or electric wireline, eliminating the need for a rig to set the reservoir and intermediate barriers. isol8’s Fusion barriers can also be used in combination with competent annular cement to deliver a ‘hybrid’ barrier envelope.
Are there any environmental benefits in using isol8’s technology?
isol8’s core technology has application throughout the entire lifecycle of a well; from well construction through to well abandonment. Using isol8’s bonded alloys in new wellbore construction could have a huge environmental impact by eliminating hydrocarbon emissions and reducing our dependence on cement to form a competent annular barrier. The primary focus in well P&A is to reduce the risk of any hydrocarbon release to ALARP (as low as reasonably practicable). By leaving the tubulars in the ground isol8’s Fusion barriers would avoid the need for North Sea operators to recycle 170,000 tonnes of steel, much of which is contaminated and may require treatment or special handling. Bonded-alloys would achieve this objective whilst simultaneously avoiding the use of cement. For every tonne of cement used there is 1.25 tonnes of CO2 produced. In new well construction. there is estimated to be up to 6000 sacks per well which equates to 255 tonnes of cement; that is, 320 tonnes of CO2. There are approximately 80,000 new wells drilled per year which makes for a staggering 25.6 million tonnes of CO2. In context, Scotland’s annual emissions are approximately 40 million tonnes. We are seeking to play our part in reducing emissions for the benefit of future generations and it is a central focus of the company. What opportunities are there for start-up businesses in the decom sector? Start-ups in their infancy are heavily dependent on grant funding and operating company sponsorship. Without financial assistance their survival is always in jeopardy. isol8 has secure grant funding from two different bodies and early stage funding from several operating companies who recognised the significant environmental and economic benefits that our bonded-alloy technology could bring. With this support we are currently planning 4 field trials of our Fusion technology with the first deployment later this year, only 10 months from the start of the tool design.
Do you see any opportunities for cross-sector diversification?
Yes! isol8 is already augmenting our bonded-alloy technology and our technology roadmap spans new wellbore construction, intervention, and decommissioning. isol8 is developing some exciting new well completion and intervention technologies that offer significant benefits over current elastomer-based sealing products.
Describe the most important decom activity that you’re involved with?
isol8 is currently planning a 4 well field trial of our Fusion product under the scrutiny of the operating companies and regulators. The first deployment will be to create a tubing barrier with bonded-alloy. The next three deployments will involve establishing a tubing and annulus bonded-alloy barrier in different wellbore geometries. Prior to each deployment the barrier will be ‘qualified’ in a test cell at downhole pressure, temperature and wellbore deviation. The outcome of isol8’s Fusion qualification tests and field trials could reduce the forecast UK P&A costs by several billion pounds.
Nov 25, 2019