ClearWELL™ is a surface-mounted, electromagnetic signalling technology which provides long-term, continuous protection from scale deposition in oil, gas and geothermal wells, pipeline systems and surface processing facilities.
Before ClearWELL™
ClearWELL™ is highly effective in preventing the deposition of calcium carbonate, barium sulphate, calcium sulphate, strontium sulphate and halite.
ClearWELL™ is installed at the surface, without interrupting production, and transmits a pulsed radio frequency signal along the tubing via a metal-to-metal connection.
After ClearWELL™
ClearWELL™ has low power consumption, which can be provided via solar power, and the performance of ClearWELL™ can be monitored remotely.
The technology is safe, environmentally friendly and has the potential to save millions of dollars in scale remediation and lost production each year.
Features & Benefits
How does ClearWell™ add value?
- Continuous life-time protection.
- Reduces or eliminates repetitive scale remediation operations such as mechanical intervention, chemical injection and acid washes, plus associated production downtime over the lifetime of the asset.
- Protects the system from a range of mineral scale adhesion such as calcium carbonate, barium sulphate, calcium sulphate, strontium sulphate and halite.
- Protects all wet tubing and internal equipment including tubulars, valves, pumps, screens etc.
- Green technology with low electrical power consumption.
- Lowers the carbon footprint and HSE risk by reducing remediation activity, transportation of personnel, equipment and bulk chemicals.
- Ideal for remote locations.
- Small site footprint.
- No well intervention or production loss during surface installation.
- Saves costly retrieval and replacement of failed equipment.
- Provides an alternative solution to the use of injected chemical inhibitors.
- Performance can be monitored remotely via a satellite link.
- Is high quality, durable and robust, designed and manufactured under ISO 9001 certified systems. It is supplied as a certified Class 1, Zone 1 model as standard, and available for use in hazardous areas (zone 1 and 2) with full ATEX/IECEx certification.
How does scale form?
Scale formation occurs when dissolved solids that are present in produced water become supersaturated. Supersaturation typically occurs due to changes in conditions such as temperature and pressure or due to the mixing of incompatible waters such as formation water rich in Ca2+ and Ba2+ and sea water rich in sulphate (SO42-). The formation of scale and its deposition on a surface follows the steps shown in the image opposite.
When a solution becomes supersaturated nucleation will begin to occur. The process of nucleation is usually described as heterogenous or homogenous. Homogenous nucleation occurs in the absence of any foreign particle or surface. Heterogenous nucleation is the formation of nuclei due to the presence of a foreign particle or an imperfect surface that allows the adsorption of the crystal material.
Heterogenous nucleation is the most common form of nucleation as it requires less energy than homogenous nucleation and can occur at lower saturation levels. Secondary nucleation then occurs as a result of the crystal surfaces that are already present and this is the crystal growth stage. Adherence typically occurs in tandem with crystal growth as part of the heterogenous nucleation process.
How does ClearWELL™ work?
ClearWELL™ technology imparts an electromagnetic field (EMF) signal into the fluid, which has sufficient energy to promote homogenous nucleation before heterogenous nucleation and crystal growth can occur. The result is the formation of many non-adhesive, microscopic crystal particles, which remain in the fluid without impacting flow performance or system efficiency.
Independently peer-reviewed studies provide evidence for the effect and efficacy of the technology:
- SPE-170898 Preventing scale deposition downhole using high frequency electromagnetic AC signals from surface to enhance production offshore Denmark (2014): https://doi.org/10.2118/170898...
- SPE-169415-MS An environmentally friendly method to control halite scale deposition: Proved case histories from Latin America (2014): https://doi.org/10.2118/169415...
- SPE-133526-PP Physical water treatment in the oilfield (2014): https://doi.org/10.2118/133526...
- SPE-114072 Two-year results of a breakthrough physical water treating system for the control of scale in oilfield applications (2008): https://doi.org/10.2118/114072...
