Innovative pH correction at Clonbollogue Ash Facility
At the Clonbollogue Ash Facility, Bord na Móna faced a pressing challenge: how to manage highly alkaline leachate that posed serious environmental risks without relying on traditional chemical treatments.
The challenge
Bord na Móna approached Enva to deliver a solution for a high pH ash lagoon at its Clonbollogue site. With strict EPA discharge conditions to meet, they needed a solution that was not only effective, but also safe, sustainable, and future-proof.
The leachate which often exceeded 12.5 pH, posed a serious environmental risk, and with strict discharge conditions set by the EPA, traditional chemical dosing methods were deemed unsuitable due to the potential for compliance breaches and additional environmental harm.
The solution
Enva’s Industrial and Water Services teams collaborated to develop a safe, sustainable alternative using CO₂ gas dosing. When dissolved in water, CO₂ forms a mild carbonic acid, offering a more controlled and environmentally friendly way to reduce pH.
To address the resulting solid by-product (calcium carbonate), a lamella clarifier was introduced for effective solids removal. The entire system was designed with automation and safety in mind, featuring pH sensors, suspended solids monitoring and auto-valve control – ensuring no untreated or overtreatment water reached the discharge point.
All components were housed in a zero-operator setup, with routine maintenance and gas replenishment as the only human intervention required.
The impact
- Treated leachate achieved full compliance with discharge license
- Fully automated, low-maintenance operation
- Zero chemical addition, enhancing environmental performance
- CO₂ sourced from a sustainable stream, reducing carbon impact
- End-to-end delivery completed in just three months
Enva combines technical expertise, innovation, and sustainability to solve complex environmental challenges. By designing a fully automated, low-maintenance system that eliminates the need for harmful chemicals, we delivered a fast, compliant, and environmentally responsible solution for Bord na Móna.
