The removal of Natural Organic Matter (NOM) via coagulation and sedimentation processes is an essential initial step in water treatment, but one that is challenging for water utilities across the world. Recent trials at Severn Trent’s Tittesworth Water Treatment Works (WTW), a 40 Mld plant located in Leek (Staffordshire, UK) have demonstrated the ability of online zeta potential measurements to provide a reliable lead measure for monitoring and controlling clarification performance and to support a new approach to coagulation optimization. Evidence suggests that the technology and approach works well irrespective of water source or clarification system, providing that NOM removal is being affected via charge neutralization.
Adopting zeta potential as the lead measure of performance is straight-forward and generates easy to understand data that can be used to reduce water quality risk, decrease chemical usage costs and improve operating efficiency. Furthermore, experience indicates that online zeta potential measurement will provide a secure platform for fully automated process control – a long term industry goal.