Increasing Energy-Efficiency for a Potable Water Treatment Plant in Switzerland with the PX

ESB collaborated with Membratec S.A. to replace the existing plant with a reverse osmosis (RO) water treatment facility to ensure an energy-efficient provision of high-purity water. The plant features a modern membrane system to remove contaminants, especially chlorothalonil products. Aiming to minimize the use of chemicals for higher water quality, the designers chose to eliminate the use of antiscalants.

However, removing these chemicals results in a lowered permeate yield from the RO system. Consequently, higher pressure and more energy are required to meet the desired permeate output. To save energy and associated costs, the designers implemented an energy recovery system using the Low-Pressure PX® Pressure Exchanger® (LP PX) from Energy Recovery.

The plant’s final capacity with first phase and second phase will be 1,200 m³/h with an RO system of 600 m³/h resulting in production capacity of 14,400 m³/day of RO permeate, which will be blended with bypassed ultrafiltrated water. The RO is integrated in a complete treatment system (ultrafiltration, reverse osmosis for half of the flow, ozonation, GAC filtration). The first phase of RO includes two PX LP180 units into each train and the fully commissioned plant will have 16 low-pressure PXs installed.

Award-Winning Water Treatment Design