Algae in a cooling tower - Fouling Heat Exchanger
Crompton Greaves, India
The light division of Crompton Greaves Ltd., located in Gujarat, is the biggest manufacturer of lamps in India. Cooling is required for various production processes. The customer use bore well water, with a high content of calcium carbonate and TDS. A Reverse Osmosis System is installed to reduce the TDS from the water, prior to its use in the cooling system.
In spite of this, a lot of scale and fouling was formed inside the heat exchangers. Both for the compressor cooling and in a jacketed vessel, where the cooling water is pumped through the jacket of the vessel in order to temperate the product in the vessel. This fouling reduced the performance of the machines a lot. In consequence, at least every three month cleaning of the heat exchanger was required.
The vessel jacket, had to be chemically cleaned at least every six months.
|Pursanova TM was installed ahead of the cooling tower, where a lot of algae could be found. Also PursanovaTMDisk were installed ahead of the heat exchanger for the compressor and at the inlet of the jacket of the vessel. As this is a rather small loop, with these two PursanovaTM, we have treated the entire cooling water system. Only a few days after the installation it could be seen how much scale was automatically washed out at the blow down of the jacket from the vessel. The performance of the compressor was stable and when the heat exchanger was opened by routine inspection after three months, the scale was almost totally gone. All the heat exchanger tubes were totally clean, there was no cleaning required as in the past, just washing the surfaces. The result at this heat exchanger is now stable for more than five years.
The algae at the cooling tower are gone, only little spots can be found today. The customer is not adding any chemicals to their system either, which leads to even more savings. The ROI of this installation was about two month. See as a well enclosed certificate. Furthermore, the customer has decided not to use the RO anymore; they use currently the bore well water directly in their system.