Aluminum plant, Saudi Arabia

An aluminum extrusion plant requires cooling for the machine presses used in fabricating products for the construction industry. An open evaporative cooling system with three cooling towers in series was chemically treated for scale, corrosion and microbiological fouling control.

The challenge

Regular monitoring indicated bacterial activity consistently in excess of 10,000,000 organisms per ml over a four week period. Significant biofilm was evident in the tower sumps, packing and distribution channels, causing blocked filter strainers and overheating in factory production.

The cooling system could not be taken offline for cleaning, and the existing non-oxidizing biocide regime, shock dosed twice per week, was failing to achieve control.

The solution

It was agreed to switch to Chlodox D2, an effective biocide and bio-dispersant. To minimize the risk of moving large quantities of biomatter initially, a low dosage was introduced manually each day for the first week, with the dose gradually increased.

The result

By week four, daily bacterial activity was measured to be consistently below 10,000 organisms per ml, a 1000x reduction from the starting point. There were no visible signs of biomatter in the tower sumps or packing. The site continues to dose Chlodox D2 and is now considering installation of an automated dosing and control system.