GEOTHERMAL

Beating bacteria for the Italian 'jobs'

At look at Millars Products' use of Geoquip's borehole remediation solutions in the Italy market

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Among Millars Products customers in Italy is the oil refinery sector, where government regulations insist that hydraulic barriers are in place to contain any potential water leakage around the perimeter of every site. The barriers direct the water into specially drilled wells, situated at every 20-30m, with the express role of stopping it seeping into the aquifer below.

It is imperative that all the pumping equipment within the wells is working to maximum capacity as, if there is a breakdown, it could have long-lasting effects on the local environment.

Giorgio Boyd, from Millars Products, explains: "While the spillage remains in the well, the water is then extracted and cleaned before being discharged into the ground.

"It's a critical process as iron bacteria will grow inside the wells very easily and, once it gets established, it can cause massive problems with the equipment and maintenance of the well, so we have to make sure it is in good working order."

To help tackle the problem, Boyd works with UK partner company Geoquip Water Solutions as the exclusive Italian importer of Geoquip's BoreSaver range of water treatment solutions. These are used to treat a cross-section of different types of bacteria, including iron-related bacteria (IRB), iron oxide and manganese oxide deposits.

One of BoreSaver's key benefits is that the treatment can take place while all the equipment is in situ, helping to ensure that downtime is minimal. Boyd says: "The fact there is no need to remove the pump or undertake a mechanical cleaning process is a real benefit as apart from this taking longer, it can also allow air into the well and, of course, the air then helps the bacteria to grow again."

The presence of a marker within the BoreSaver solution also allows Boyd's team to guarantee that no chemical residue is left in the water supply.

One treatment will usually be enough to remove the deposits that have built up and the solution is safe, easy to use and biodegradable.

Another sector where Boyd works with major customers across the country is the geothermal arena.

While introducing a geothermal system into commercial or domestic properties can deliver energy saving benefits of around 30 per cent, this only applies if systems are properly maintained, which means staying on top of potential bacteria growth.

"Like any equipment, if it is fouled through contamination, it will become much less efficient and then the customer is unhappy with how it works. With geothermal, you have water going in and out of the ground to heat or cool the system, so it stands to reason that bacteria can take hold and start to cause problems," he said.

He believes that no matter what section of industry, if there are problems with boreholes or wells underperforming, becoming less efficient, providing lower quantities and quality of water; then bacteria is most likely to be the culprit.

Testing and inspection

Boyd has a two-pronged plan of attack. The first is to use a biological activity reaction test (BART) kit, which is both simple and cost-effective to use. It involves taking a water sample (container provided) to allow the user to see both if bacteria present and what type it is - for example, iron-related bacteria, sulphate-reducing bacteria or slime-forming bacteria.

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The test vial (centre) once it has been removed from the outer dispenser of the biological activity reaction test (BART) kit

With the tests carried out on-site, over an eight-day period a series of indicators will develop within the sample vial. Typically, these will present as:

  • If iron-related bacteria is found, foam will be produced and/or a brown ring develops inside the testing tube
  • If sulphate-reducing bacteria is found, foam will again be produced and a black ring may develop around the interior vial of the testing tube.
  • If slime-forming bacteria is found, a cloudy or gel-like growth will develop

Identifying the specific bacteria allows the correct treatment solutions to be applied quickly and effectively, flushing out the bacteria and preventing further damage to water quality or corrosion of equipment.

Further testing can then be carried out - both after the treatment and ideally at six-monthly intervals - to ensure the problem has been eradicated.

"These tests can be done quickly and simply, without having to make a major investment, allowing the customer to see if he has a bacteria problem and then look at a treatment and/or a further investigation programme," adds Boyd.

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A Laval R-CAM borehole camera from Geoquip being used to investigate a borehole

 

The second line of investigation will be to use a downhole camera to take a closer look at what is happening underground, helping to rule out external damage or blockages. For this, Boyd uses a Laval R-CAM borehole camera, also from Geoquip. One of the biggest benefits, he says, is that it has a very small diameter, enabling him to use the camera in boreholes without removing the pump.

"Customers are often surprised by what we find - it can be anything from little prawns or frogs to damage caused by previous rough rehabilitation or cleaning; sometimes a well will collapse due to its age and once we surveyed a well which had been damaged by an earthquake."

By using either the BART kits and/or the use of a camera, Boyd says a cleaning, repair and treatment solution programme can be put in place to return the borehole to full capacity.

From then onwards, he recommends putting in an ongoing maintenance programme with regular checks to ensure any future build-ups of bacteria can be identified and treated before they become a major problem.

Got a story? Email: duncan.moore@aspermontmedia.com