Limescale in air conditioning

Customer: Kemwell Pharma in Bangalore, India

Kemwell Pharma Pvt. Ltd. is one of India's leading pharmaceutical manufacturers. Both its headquarters and its main production facility are in Bangalore. It also has a production branch in Sweden.

The Bangalore company operates several air-conditioning systems to cool its production facilities. The main problem to be solved was severe limescale buildup in the condensers.

This scaling has two negative consequences: higher temperature differences and increased differential pressure at the condensers. Production runs around the clock, leaving little time or opportunity to shut down, switch off and thoroughly clean the air-conditioning system.

The user therefore had to accept reduced performance and higher operating costs. The cooling system's feedwater has a TDS of between 600 and 720 ppm, while in exceptional cases the circulating cooling water can reach a TDS of up to 12,000.

The result

The picture on the left shows a MERUS Ring installed on the condenser inlet line.

A visible improvement in the existing installation was evident after just a few weeks. Before installation, the required temperature difference was between 5° and 6°C. It improved by one degree and has now stabilized at 4° to 5°C.

A further improvement can be seen in the compressor's outlet pressure. Before installation, the pressure was 0.4 kg/cm². Now, after the MERUS Ring dissolved the limescale deposits, a pressure of 0.6 kg/cm2 is achieved.

The compressor's energy consumption at a temperature difference of 6°C was 6.73 kWh.

At the cooling water temperature of 5°C now achieved, energy consumption has fallen to 3.37 kWh. This means a 50% electricity saving.

Extrapolated, this represents direct electricity savings of more than 80 kWh per day, or 2,400 kWh per month. Assuming the electricity is supplied by a coal-fired power plant (CO2 emissions from coal in India >1,000 g per kWh), the use of MERUS Rings adds up to almost 50 metric tons of CO2 savings per year!