Cooling Tower Optimisation at Data Centre Facility

The primary cooling tower system, measuring approximately 40,000 litres, was experiencing severe inefficiencies in conductivity management and bleed-off control. The water softener was regenerating far more frequently than expected, using saturated brine solution (sodium chloride) with each regeneration cycle.

This excessive use was causing elevated chloride levels in the effluent stream, as well as breaches of the site's environmental discharge licence. In turn, this led to false Chemical Oxygen Demand (COD) readings, due to chloride interference, along with water wastage estimated at 90% loss through inefficient bleed-off. This could’ve had potential legal consequences, with fines ranging from £2,500 to £50,000, and a huge loss of client confidence in water treatment management

Cooling Tower Optimisation at Data Centre Facility

Solution

SOCOTEC UK and Ireland was contacted, with its water treatment specialist, Josh Martin, implementing a comprehensive monitoring and optimisation programme to help identify the problem.

Through detailed analysis of conductivity measurements - total dissolved solids - and evaporation cycles, Josh identified that the system was failing to properly manage the balance between salt concentration build-up and controlled bleed-off.

As part of the fixes Josh recommended was the identification of suspected leaks through the analysis of water meter data and the use of tracer dye. This led to site lowering the sump level and finding a previously unidentified wastewater stream. This has now improved water and conductivity management, improving the cycles of concentration to prevent excessive water waste.

This was accompanied by a reduction in water softener regeneration frequency, and the identification and correction of laboratory sampling dilution errors adversely affecting COD readings, as well as the implementation of ongoing monitoring protocols.

Josh's chemistry-based background proved crucial in identifying that chlorides were interfering with COD measurements, leading to false breach readings.

SOCOTEC UK and Ireland was contacted, with its water treatment specialist, Josh Martin, implementing a comprehensive monitoring and optimisation programme to help identify the problem.

Josh's chemistry-based background proved crucial in identifying that chlorides were interfering with COD measurements, leading to false breach readings.

Results

SOCOTEC’s programme of fixes delivered exceptional results for its client. There was a 90% reduction in water usage through proper bleed-off management, which resulted in significant cost savings from reduced water consumption and chemical usage.

The client’s environmental compliance was restored, with chloride levels reduced from breach levels to well within the discharge licence parameters. False COD breaches were eliminated through corrected laboratory analysis methodology.

Reduced bacterial contamination – aerobic bacteria levels dropped from borderline to near-zero because of improved biocide retention and contact time.

Ultimately, SOCOTEC’s response earned an expansion in its agreed contract with its client, with over 305% more value now in place – this included SOCOTEC’s weekly visits, chemical allowance, and additional effluent stream sampling. There was an improvement in client relations, with monthly meetings reduced as confidence in the water treatment management programme was restored, and SOCOTEC’s client avoided any risk of fines and litigation linked to the state of the cooling system.

The project demonstrated how expert water treatment management not only resolves immediate operational issues but also delivers substantial cost savings, ensures regulatory compliance, and protects clients from legal and reputational risks.