Algae Cooling Tower

User: Crompton Greaves, India

The light division of Crompton Greaves Ltd., located in Gujarat, is one of the oldest lamp manufacurer in the world and the biggest manufacturer of lamps in India.Algae in the cooling tower

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, were 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 3 months cleaning of the heat exchanger was required. The vessel jacket, has to be chemically cleaned at least every 6 months.

The Result – Algae and Scale was gone

One Merus Ring was installed ahead of the cooling tower, where a lot of algae could be found. Additionally ahead of the heat exchanger for the compressor and at the inlet of the jacket of the vessel one more Merus Ring has been installed. As this is a rather small loop, with these two MEURS rings, we have treated the entire cooling water system.

Only a few days after the installation it could be seen how much scale was washed out at the blow down of the jacket from the vessel.
The performance of the compressor was stable. When the heat exchanger was opened by routine inspection after 3 months, the scale was almost totally gone. All heat exchanger tubes were clean. There was no extensive cleaning  required as in the past, just washing the surfaces from time to time was sufficient. This heat exchanger is now stable for more than 5 years.

The algae at the cooling tower are gone, only little spots can be found today. No need anymore for the customer to add any chemicals to their system either, which leads to even more savings. The ROI of this installation was about 2 month.
Furthermore  the customer has decided not to use the RO anymore; they use currently the bore well water directly in their system.