Materials for Geo Energy

The main research in this field concentrates around 4 different topics.

1. 1. DECOMMISIONING AND RE-USE

Natural sealing

Traditionally cement is the sealing material of choice in the well technology. However shrinkage during curing and slow degradation processes compromise long term stability. Therefore, for plugging wells on decommissioning, alternative sealing materials and techniques are being developed to ensure a (infinitely) long sealing of abandoned wells. TNO is involved in various developments in cooperation with operators and regulatory authorities. For plugging TNO investigates how naturally occurring sealing materials like dedicated clays and salt compositions, can be used for plugging. Their down hole sealing properties are investigated and optimized and related placement techniques are developed.

Durability

The long term stability is important for sealing materials and for materials that are left in the well after abandonment. Also if wells are used for a different application than original stability issues can occur. TNO investigates the long term behavior and runs test that allow prediction of long term stability in down hole conditions

2. 2. SCALE AND DEPOSITION

Changes in temperature and pressure or combination of different liquid streams can cause some components become insoluble and precipitate on a wall of an installation or in the pores in a reservoir. The research group investigates the phenomena at the interface of deposition and tries to come up with economically sound mitigation methods. In the case of aqueous streams and steel pipes scaling and corrosion are closely related.

Set-up capable of monitoring deposition dynamically on flat substrate

3. 1. 3. GEO-THERMAL ENERGY

   The energy recovery from geothermal sources is in full development. A lot of the technology used in geothermal is copied from the oil and gas industry. There are however strong differences. E.g. for the high enthalpy wells the temperatures are much higher than in oil and gas reservoirs. TNO develops concepts and materials to allow good functioning of the well at these conditions.

   • The high temperatures also give specific scaling challenges.
   • Lowering cost is essential and therefore cooperating in the field of composite casings.

Feasibility of use bentonite plugs for sealing on abandonment oil and gas wells

4. 4. ENHANCED OIL-RECOVERY

Although we need to reduce the CO2 as much as possible, for some considerable time we will be using a lot of oil and there is still a strong demand to improve the amount of oil that is recovered from existing reservoirs. TNO develops new methods that enhance the oil production under extreme conditions like very high salinities and elevated temperatures encountered in some reservoirs.

The research in these areas is performed both in the framework of international consortia and in business to business projects. We support companies in the development in these area’s most often operators and service providers.

In general this research requires a multidisciplinary approach and we often rely on cooperation with specialists at project partners or TNO departments like Applied GeoScience, Heat Transfer and Fluid Dynamics, Structural Reliability and Structural Dynamics or Academic groups.