DrillWell - Drilling and Well Centre for Improved Recovery

DrillWell's vision has been to unlock petroleum resources through better drilling and well technology. The Centre has, in a safe and environmentally friendly way, contributed to value creation through better resource development, improved efficiency and reduced cost.
Well construction represents approximately 50 percent of the total field development cost. DrillWell aims to make a difference by basing new technology on a better understanding of the physical processes taking place, both during well construction and during the well lifetime. The models are based on experiments and are continuously being validated by comparison with measured data from drilling operations offshore Norway. The laboratory experiments carried out in DrillWell have served to develop and improve the models targeting implementation in commercially available software. A growing and considerable challenge faced by the petroleum industry is the strict requirement of permanent well plugging and abandonment (P&A). There is a considerable need for research and new technology within this field, both to reduce cost and to ensure that the work is done satisfactory - for eternity. DrillWell researchers have investigated properties of existing and new plugging materials and the possibilities to map the performance of leakage barriers in existing wells. Application of DrillWell technology has already contributed to substantial savings during drilling operations. One example is the application of NORCE software that calculates the transport of cuttings out of the well. This software is now in operation in the industry. DrillWell has also received feedback from drilling operations, stating that only 50 percent of the planned drilling time has been spent. We noticed a significant decrease in unwanted incidents like non-planned technical sidetracks. Accordingly, for the model-based technology, now used for 180 wells, only 16 technical sidetracks have been reported. In comparison the Norwegian Petroleum Directorate reports that for 30 percent of the wells drilled in the period 2013-2016 sidetracks have been required. This illustrates that using this technology surely allows for significant cost reductions. A specific NCS operator using the technology has reported potential savings of 180 million USD annually within the company. During the summer 2017 Equinor applied automated drilling on a semi-submersible rig for their first time, reporting savings of approximately 100 million NOK for two well sections drilled in the Barents Sea. 
In a unique and fit for purpose laboratory set-up at SINTEF, studies are performed on how fractures develop in the cement of wells exposed to temperature and pressure variations. For the first time, the flow of gas and fluid through the fractures are visualized in 3D by use of CT (Computed Tomography). For well construction, it is important to understand how wellbore irregularities affect the displacement process and whether local irregularities can affect the quality of the cement above the wellbore irregularities. Laboratory and at the full-scale experiments have been performed to investigate how an eccentric inner string and a locally enlarged hole size affect fluid displacement in nearly horizontal wells. The detailed displacement experiments at the SINTEF laboratory facilities and the full-scale cementing experiments at Ullrigg have been compared with three dimensional numerical simulations, including also the validation of Schlumberger`s methodology for cementing operations. The unique experimental data are essential for gaining confidence to simulation tools developed for planning cementing operations. The facilities at NORCE and SINTEF are accessible for industry and authorities to conduct testing and documentation of barrier quality. This is crucial to further develop barrier materials and to make better decisions for permanent well plugging.

With a vision to unlock petroleum resources through better drilling and well technology, DrillWell has contributed with new knowledge and technology. The main objective has been to improve drilling and well technology, provide improved safety for people and the environment and value creation through better resource development, improved efficiency in operations and reduced cost. A substantial contribution has been made to cost reductions achieved during the period 2014-19, which were in the range of 30-50%.

Highlights of scientific results cover

• Development and application of a transient model for estimating the distribution of drilling cuttings in the well and the transport to surface
• Development and application of a transient drill-string torque and drag model
• Development and application of models for drill-string torsional and axial vibrations
• Development and application of a model for reconstructing drill-string movement
• Measurements of gas solubility in drilling fluid base oil which is important for well control while drilling high-pressure and high-temperature wells
• Full scale well cementing experiments showing the potential for leaving the pipe in hole when plugging and abandoning wells
• Testing of well barrier verification tools

The results have been utilised by the participating oil companies and their service providers, improving services and proving new technology. Our focus on the drilling process optimisation and plugging and abandonment of wells has in particular assisted the industry with valuable tools and knowledge for planning and executing drilling and well operations, for automated drilling control as well as cost efficient plugging and abandonment of wells.

According to The Norwegian Petroleum Directorate (Oljedirektoratet) the frequency of technical sidetracks was greater than 30 percent in the period from 2013-2016. Applying technology developed in DrillWell has so far reduced this frequency to 9 percent.  One of the operators using this technology reports potential savings of 180 million USD annually. In 2017 Equinor implemented automated drilling on rigs and reported savings of approximately 100 million NOK for two well sections in the Barents Sea. Technology developed in the Drilling Process Optimization project was important in order to enable drilling automation on rigs. Equinor and Wintershall DEA are now deploying the technology on seven rigs in collaboration with Sekal and NORCE.

The research partners have established plugging and abandonment of wells as a strong new research area and have also expanded the research fields of drilling process optimisation, well control and well integrity.

Research activities with drilling process optimisation, drilling automation, well control, geo-steering and well plugging and abandonment of wells are continuing in established spin-off projects. After the first development and patenting of a geopolymer plugging material in DrillWell the company SafeRock was established and the technology is being further developed with support from oil companies. A national infrastructure is also being developed for plugging and abandonment of wells in a cooperation between the DrillWell research partners, which will be available to academia and industry working to develop new knowledge, technology and methods to secure abandoned wells avoiding leakage and to reduce abandonment costs.