Ultra-pure water for steam turbines produced using resource-efficient processes

Project requirement

The existing full desalination plant required replacement, and the operator was seeking a safe and sustainable alternative that did not involve chemical regeneration. The requirement was to ensure a reliable supply of consistently high-quality ultrapure water to the steam turbine. In addition, the overall system needed to operate in a more resource-efficient manner, reduce water losses, and be easily monitored and controlled via a central interface.

Herco solution

A customised pure water solution was developed, including a permeate-staged design, integrated degassing, EDI and a downstream polisher. This made it possible to avoid chemical regeneration and even a water softener. A separate concentrate treatment system further increased the water yield, whilst the overarching control system acts as a central interface for the entire system.

Plant engineering

The system combines several precisely coordinated process stages to ensure high water quality, operational reliability and resource efficiency within a centrally controlled integrated system.

• Pre-treatment stage with reversible fine filters, system separators (both redundant) and plate heat exchangers on a single frame
• Redundant, permeate-staged reverse osmosis systems with antiscalant and bisulphite dosing
• Integrated CO₂ membrane degassing
• Elektrodeionisation (EDI) to maintain water purity
• Mixed-bed polisher as the final stage
• Separate concentrate treatment line with tanks, pressure boosting system and brackish water system
• A higher-level control unit that represents the entire system and serves as the central interface for the client’s building management system