In the relentless pursuit of a sustainable future, HydraWell is a pioneer in the energy industry where a successful balance of innovation, environmental stewardship and decarbonisation provide the pillars for growth, sustainability and helping set the pace for the sector.

From the company’s roots in Norway and now with a significant presence in the UK and Malaysia too, adaptable solutions have always been placed consistently at the heart of HydraWell’s ongoing drive to re-think existing well integrity operations. Forming its nucleus is the revolutionary Perf, Wash & Cement (PWC®) technology which provides a nimble, flexible and cost-effective method which is much in demand across a range of applications – from permanent plug and abandonment and slot recovery to restoring annular integrity and casing shoe repair – and in a growing number of sectors.

Throughout the company’s history since it was created in 2008, the team has worked extensively to foster cutting edge solutions which keep HydraWell at the forefront of its sector, but this has always been carefully balanced with keeping the key principles of the revolutionary PWC® remediation method consistently at the heart of everything.

Traditional, incumbent methods were often associated with high technical risk, high cost of execution and significant carbon emission because of the extensive support required during the delivery phase. The introduction of HydraWell’s PWC® changed all that, and revolutionised the essential process of well abandonment. By also drastically reducing the carbon footprint of well P&A operations, PWC® is not only cheaper and safer but also better for the environment and represents a step-change in decarbonisation efforts.

Technology pioneer

During 2010 the company introduced the HydraWash™ cup based, low pressure cement remediation system to the market. The system was designed to replace the high risk, material cost, time consuming alternate methods for getting access to isolate zones of flow potential. Successfully deployed in wells with poor or no cement across the annulus between casing and formation, the system was adopted quickly with clients recognising the time, cost and efficiency benefits offered by the technology.

As the limits of the HydraWash™ system were reached, and with an improved understanding of clients’ needs, a new generation of tools were developed in 2013. The first generation HydraWash system was licensed to others and HydraWell developed and progressed to a more versatile jet-based PWC® system marketed under the HydraHemera™ banner.

The second generation PWC® system, HydraHemera™ is deployed across a much wider range of applications targeting multiple annuli in more challenging wellbore environments. The high pressure, technically superior jet-washing tool, cultivated for the same applications as its predecessor, became the solution of choice in single and multiple casing applications, thanks to its enhancements offering heightened efficiency and benefits including the ability to maintain full circulation rate, easier and more predictable operations, less pressure exerted on formation and not relying on “limited entry” to force fluid through all perforations. Delivering a 98% plugging success rate, customers know they are in safe hands with HydraWell.

Innovation didn’t stop with remedial wellbore activities. Developing a method for reliably testing in-situ barriers, squeezing shales and squeezing salts and then isolating the wellbore internally was pioneered by HydraWell in 2015 with the introduction of the annular integrity test (AIT) tool.

Post perforating, the integrity of the AIT is verified in blank casing before the cups are positioned across the lower perforated interval. Pressure is applied between the cups to test the integrity of a suspected natural barrier. If the natural barrier is competent i.e. no return is observed from the upper perforations, the natural (formation) barriers are verified.

Testing with an AIT can be repeated to confirm the initial test or moved in the wellbore to test a secondary area. Post testing an internal cement plug can be set or the tool can be retrieved depending on the next operational steps to be performed.

The digital revolution

In response to a drive towards de-risking operations prior to execution, HydraWell with client support, collaborated in the development of a ‘digital twin’ model for barrier remediation and installation in wellbores. Computational Fluid Dynamics (CFD) is a branch of fluid mechanics that uses computational power to perform the complex calculations required to simulate the free-stream flow of fluid and the interaction of that fluid with surfaces as well as in the environment through which it is flowing. In 2016 HydraWell began utilising CFD to simulate fluid flow and pressure dynamics in wellbores specifically within an annulus for remedial barrier placement and verification. The method’s ability to model complex geometries, fluid properties and dynamic conditions generates comprehensive understanding of fluid behaviour within the wellbore environment.

In P&A design, barrier placement and verification are critical to decommissioning wellbores ‘in perpetuity’. The use of CFD in a digital twin environment helps in predetermining outcomes, optimising the barrier placement process and ultimately assists in verifying the suitability of the placed barrier.

Ensuring effectiveness of the operation and the placed barrier in a virtual environment, replicating actual conditions, allows the engineer to confirm that an operation delivered as planned will prevent unintended fluid migration between geological formations and the surface. This verification by CFD is a significant advancement over traditional verification methods which involve mainly non-empirical methods. Traditionally barrier testing and subsequent validation by a Technical Authority can sometimes rely on personal observations and subjectivity to determine the effectiveness of a placed barrier.

Evolving technology, understanding of the limits of subjective assessment and recognition of a potential knowledge gap in a growing well decommissioning industry, validates the scientific approach to ensuring barriers are designed, installed and verified with confidence.

Further innovation

A subsequent drive to increasing the operational envelope of PWC®and address more challenges from a growing global customer base gave rise to the HydraTyphon™ PWC® tool which was developed to address more challenging barrier placement applications with a specific focus on larger casing sizes with heavy or high viscosity fluid environments.

Simultaneously, and against a backdrop of HydraWell’s 500th plug installation in 2022, HydraCT™ was developed and introduced to the market continuing the unrivalled track record for development and innovation.

HydraCT™ facilitates PWC® operations conveyed by coiled tubing or small jointed pipe.

As an industry first PWC® system for rigless abandonment, HydraCT™ uses the fluid energy to not only penetrate and remove debris in the annulus space but also as a propellant creating a rotational force downhole which replaces the requirement to rotate the entire workstring from surface. During the cleaning of the casing and annulus, wash fluid is circulated through the coiled tubing to the tool which incorporates a hydraulic brake. As fluid exits the nozzle head, flow is transformed to RPM downhole. Rotation of the jetting tool facilitates the formation of turbulent vortex flow which cleans the annulus with multidirectional nozzles focusing the high energy jetting force and displacing annulus content with the fresh wash fluid.

Specifically designed for low footprint applications the use of HydraCT™ has the potential to cut CO₂ emissions by up to 80% and reduce costs by almost 60% per barrier set in the wellbore. The stride forward HydraCT™ represents in terms of eliminating the need to mobilise a rig to site is considerable and comes from an unstinting desire to do new things.

The benefits of the HydraCT™ PWC® system were recently appreciated during the annular isolation and P&A of eleven wellbores on a project in Alaska. The Project needed a more cost-effective method for use in a remote area where rig availability is extremely limited. In a single run per well, HydraCT™ eliminated the need to mobilise a rig to site and cut the requirement to run drill pipe for remediating the annuli without compromising barrier quality or barrier verification – and all in less than 24 hours for each well.

With the portfolio remaining firmly focused on achieving optimum results, HydraWell will continue to strike a successful balance of remaining true to its roots whilst pushing boundaries and inventing pioneering technologies that will transform well operations around the world.