15 Nov 2018
By David Stephenson, CEO of Deep Casing Tools.
Over the next decade, 1,400 oil and gas wells are forecast to be abandoned on the UK Continental Shelf, at a cost of around £7 billion; a huge financial burden and an equally huge opportunity for innovation.
Plugging and abandonment (P&A) is one element of the decommissioning process which certainly delivers on the complex and challenging front. It’s the process by which a well is closed permanently, usually after production has drained the reservoir or when there is insufficient hydrocarbon potential to complete the well.
A technically demanding and costly activity, P&A typically accounts for about 45% of the projected total decommissioning costs. This is largely driven by the cost of drilling rigs that are needed for the heavy lifting equipment required to pull tubulars and cut casing.
So, exploring new or ‘rigless’ methodologies presents a big opportunity to reduce well P&A expenditure and total decommissioning costs. New methodologies should provide more effective results, which is vital when you consider that, in the UK, responsibility for well integrity is enduring, and field operators must remedy any future failure after P&A. The financial, not to mention environmental implications, could be very onerous indeed.
I joined Deep Casing Tools as CEO earlier this year, following a 20-year career in the oil and gas sector, during which I’ve managed substantial businesses in the UK, the Middle East and South East Asia. Having established a strong track record in business improvement and product development, I want to tackle the well abandonment challenges that I’ve witnessed first-hand in the field.
At Deep Casing Tools, we have built a reputation for providing cutting-edge technology to drill, optimise and now abandon oil and gas wells. Unfortunately, the current technologies being utilised for P&A – cut and pull; perforate and wash and, as a last resort, section milling – can create significant challenges to operators and service providers. Research shows that around 20% of all pulling operations take longer and cost more than anticipated.
The improved quality of the cementing around the casing in recent years, and simply the length of time these casings have been in the ground, has exacerbated the problem, with current technologies no longer working in many applications.
Quite aside from the financial and operational implications, there are also environmental considerations. Any new solution or technology which reduces the potential impact on the surrounding environment, whether subsea or onshore, is obviously a good thing.
In an ideal world, a revolutionary solution would emerge onto the market and replace these existing technologies. But, until that happens, is accepting the status quo our only option?
Having recently discussed this thorny issue with operators and regulators, I am acutely aware that standing still isn’t an option. The industry is crying out for new technology: something that will streamline the entire P&A process for everyone, something that will reduce risks and uncertainties and increase viability and cost-effectiveness.
At Deep Casing Tools we are developing an exciting new technology that will do just that. Our ‘cement bond-breaker tool’ concept is an industry first, which will work in conjunction with existing technologies to expedite and enhance current P&A processes.
A mechanical device used to flex, or manipulate a casing within its elastic limit downhole, our tool will break the bond between the cement, or in some cases barite, and the casing, driving it away from the casing, and also breaking down the structure of the cement and barite. This addresses the huge problem where casing cannot be pulled, and cement cannot be washed out from behind casings.
Where the cement bond breaker tool will really come into its own is in the reduction of risk and uncertainty for operators. As things stand, the decision path around P&A can be an unstructured one. Given that the condition of the cement down-hole is generally an unknown quantity, the decision on whether to use perforate and wash, where to cut and pull, or section mill, is often based on trial and error, swelling the already prohibitive costs.
Our research has demonstrated that the tool will be effective on even the strongest cement. Removing the guesswork from the operation will inevitably lead to a more clear and structured decision-making process across the board. Increasing confidence in this way can only result in a virtuous cycle of optimised operations in the future.
Decommissioning is, by necessity, occupying a significant proportion of operators and service providers’ attention, but equally important is the issue of maximising the economic recovery of fields. This is where our cement bond breaker tool can add yet more value. It could be deployed to recover platform slots for new production wells.
Whether reducing the costs of decommissioning or maximising economic recovery, we believe our cement bond breaker tool literally has the potential to break the mould and drive value.