The reduced production caused by scaling on pipes and within the geothermal reservoir poses a major problem for geothermal energy production. Calcium carbonate and sulfide scaling can occur in the production well of a geothermal plant, while silica scaling can occur in the injection well and parts of the geothermal reservoir. As the scale builds, the aperture through which geothermal fluids flow shrinks and flow is reduced. Silica scaling within the reservoir can permanently reduce its permeability. In general, scaling problems can be so severe as to partially or completely close a power plant. Common scaling removal techniques, such as reaming clogged pipes and acid washing, remove the scale but pose problems of their own. Reaming pipes can be effective in cased portions of the well, but this technique is ineffective if the slotted liner of the well is clogged. Acid washing can cause corrosion in the pipes and degrade their integrity. In this paper, we present an alternative scale reduction technique in the form of nanobubbles. These nano-scale bubbles have unique chemical and mechanical properties that may be advantageous in the removal of scale. Circulating nanobubbles through the geothermal system by injecting them into the geothermal fluid could either prevent scale from attaching to pipe walls or cavitate scale that has already built up, thus reducing the need for previously discussed removal techniques.
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