Fouling within geothermal bores can be caused by a number of factors and will typically occur in both injection and production bores. Due to the nature of down hole conditions it is an issue that can never be completely eliminated, though with the right method of injection control it can be substantially slowed and reduced. Fouling issues prevent bores from operating at their peak performance and can promote corrosion, lowering the overall life span of the bore.
Issues experienced with production bores may be:
• Lower bore production rates (yield) due to fouled screen apertures
• Higher pumping draw down due to fouled screen apertures
• Submersible motor overheating due to reduced yields
• Submersible pump deterioration due to entrained sands and solids
Issues experienced with injection bores may be:
• Lower injection flow rates due to fouled screen apertures and fouled aquifer porosity
• Higher injection pressures due to fouled screen apertures and fouled aquifer porosity
The fouled screen apertures and fouled aquifer porosity can be caused by any combination of bio fouling, calcite formation, silted sands and mineralised deposits formed by chemical reactions between the injection and extraction bore water chemistries.
There are a number of treatment options to cater for the different forms of fouling however injection bores typically require a program consisting of:
The typical procedure outlined above ensures that not only are the fouled screen apertures cleaned (similar to a mechanical brushing technique), but more importantly the fouled aquifer porosity issue is addressed, ensuring a more effective and longer lasting clean out without any mechanical damage to the bore.
AGE has a proven track record remediating geothermal bores and will be happy to discuss your particular bore symptoms, propose tailored solutions and to provide client references for similar work where requested.
In addition to the geothermal bore cleaning services AGE Developments provides, we also manufacture a range of ASR (Aquifer Storage & Recovery) and AIC (Aquifer Injection Control) equipment to assist in minimising geothermal injection bore fouling issues.
Client Reference List
Below is a list of Geothermal and Injection bore clients AGE Developments have successfully worked with:
To find out more or to discuss any specific needs you have – be it for off the shelf equipment or custom designed equipment, contact AGE Developments.