Milan (Industrial Complex) Case Study
Thursday, 25 November 2010
The geothermal air conditioning system servicing a 150,000m2 retail/industrial complex in Milan was experiencing blockages due to severe contamination of iron related bacteria (IRB). The system, producing 6MW, comprises nine geothermal plants, three wells and 10km of pipework between 250mm & 10mm diameter.
Iron related bacteria was found in the extraction wells, in the primary and secondary heating loops and in the convector heating systems in the offices where the pipes are as small as 10mm. Typical symptoms included poor flow, orange brown residues and high working pressures in the secondary system. The system was clogged and in some cases completely blocked by the bio film and oxide residues produced as a direct consequence of the IRB.
After treating the system, the M&E contractor later reported a doubling of performance on the three worst affected plants with an increased performance across all plants. The product is continuing to be used in a preventative maintenance capacity at the plant.