Secondary and tertiary recovery of light crude fields

Well treatment truckMost light crude oil fields have primary recovery rates of only 20%-30%. After that, reservoir pressure drops, and the oil cannot be pumped naturally to the surface.

There are multiple options to stimulate further the reservoir to recover more oft the oil in place. Viscos Energy binary mixture (BM) technology is one of the most efficient technologies to perform such enhanced oil recovery (EOR).

In comparison to other EOR technologies, the binary mixture application has a small surface footprint with most of the treatment being performed directly in the formation.

The binary mixture is a combination of the effects of the following chemical reactions:

  1. Cleaning effect in the productive zone (paraffin cleaning, but also oil is further separated from rock and sand formations)
  2. Better mixing of oil and water and therefore better recoverability because of temperature increase (for example, heating of oil with an API of 33 by 100 degrees centigrade, the viscosity is increased 6-7 times) and mixing of solvent gases from the reaction (CO2, NO) with oil/water
  3. Increase in Reservoir pressure
  4. Potentially fracking effect

Not all of these effects have to happen simultaneously, but can be controlled.

After the initial BM reaction, the increased temperature and release of oxygen (O2) leads to a reaction with the oil, sustaining further heat generation without additionally having to supply Chemicals.

Re-treatment of fields prepared for hydro-fractures

Binary mixture technology can be leveraged in shale oil formations that were previously hydro fractures were applied. Such fields have typically steep decline curves at the end of a field's life cycle. This cycle can be prolonged by applying binary mixture treatment at the beginning of the field's decline.

Water content

One important factor to watch in the application on light crude fields is he water cut in the productive zone. Too much water would lead to inefficiencies, as the water would heat up and absorb too much of the energy generated with our BM reaction. Ideally, a reservoir should have a water cut below 50%, however higher cuts are also possible, albeit at lower efficiency.

 

 

Case studies

  • Lukoil / Usinsk area: Stimulation of 40 year old oil field for secondary production; production increase by a factor 3
  • Texas: retreatment of 50 acres field