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Supercritical water could spur geothermal revolution

Supercritical water could spur geothermal revolution Flow test of the IDDP-1 well at Krafla, Iceland (source: Kristján Einarsson)
Francisco Rojas 14 Oct 2014

The result of using Supercritical water is radical increase of power output from one geothermal well yet the necessary conditions are very specific and currently only available on selected areas around the world.

In a recent blog post, the benefits of Supercritical Water (SCW) are detailed and the consequences it might have for the geothermal industry. As stated in the blog, SCW is a specific state of water which is very hot and under so much pressure that it exists somewhere between water and steam. The boundary of this state are conditions with temperature higher than 374°C (705°F) and pressures over 22.1 MPa. SCW has several interesting features; its main disadvantage is the fact that it is very corrosive. On the other hand, advantages can be utilized in several industry segments.

Nowadays the most famous attempt to utilize the supercritical water as an energy source is the Iceland Deep Drilling Project (IDDP). The approach in this case is simple; developers are trying to drill a well two miles deep into the active Volcano crater, Krafla and that way to reach 400-600°C hot supercritical hydrous fluid at a rifted plate margin. When this fluid hits the surface, it will have much more energy than fluid in conventional thermal cycles. The result is radical increase of power output from one geothermal well. It is necessary to mention that geothermal conditions in Iceland are extraordinary and there are just a few other locations in the world with similar opportunities. More detailed information you can find on IDDP.

Therefore, for the utilization of this phenomenon is required an improvement of current drilling methods for accessing the geothermal reservoirs with supercritical conditions. On the other hand, SCW could be an effective support during the process of drilling. Its aggressive and corrosive nature can are suitable for increase of the disintegration process. Naturally, the drilling tool with high corrosion resistance is required. This process is mainly suitable for drilling techniques based on thermal approach, such as plasma, which offer high heat flow required for supercritical conditions.

SCW could be utilized not only in geothermal segment, but according to recent research, using it in the process of material or waste disintegration is very promising.

To read the rest of the blog entry, please follow the link below:

Source: Geothermania