Technology

Technology Overview

The Hydraeon alkaline water electrolyser is INEOS’ purpose-built solution for large-scale green hydrogen production, leveraging 130⁺ years of electrolysis expertise from its chlor-alkali BICHLOR™ platform.

Key innovations:

Core advantages:

• Inherits BICHLOR™’s modular, low-pressure safety design but eliminates chlorine-related risks.
• Proprietary electrode coatings with 8-year refurbishment cycles (vs. industry-standard 5 years).
• Compatible with intermittent renewable energy, enabling grid-balancing applications.^[1][4]

Process Flow Description

The Hydraeon process follows these stages:

1. Water Pretreatment:
   • Demineralized water is mixed with potassium hydroxide (KOH) to form the electrolyte.
   • Filtration removes impurities to protect membrane integrity.^[1][4]
2. Electrolysis:
   • Electrolyser stack: Modular cells with nickel cathodes and MMO-coated anodes split water into H₂ and O₂:
     2H₂O → 2H₂ + O₂
   • Operating conditions: 80–90°C, low pressure (0–5 bar), 10 kA/m² current density.^[1][7]
3. Gas-Liquid Separation:
   • Hydrogen separator: H₂ gas is cooled, dried, and purified (membrane/PSA systems).
   • Oxygen venting: O₂ is safely released or captured for industrial use.
   • Electrolyte recirculation: KOH solution is filtered and returned to the electrolyser.^[1][4]
4. Compression & Storage:
   • H₂ is compressed to 20–30 bar for pipeline injection or stored in tanks.

Key Differences from BICHLOR™

Pilot Projects

1. INEOS-ENGIE Antwerp (Belgium):
   • Objective: Replace 10–20% of natural gas with green H₂ in a gas turbine at INEOS Phenol’s CHP plant.^[2][5][6]
   • Implementation:
     • EQUANS-designed “mixing skid” blends H₂ with natural gas.
     • Initial 10% H₂ injection successful; scaling to 20% underway.^[5][6]
   • Outcome: Reduced CO₂ emissions by ~1,200 tonnes/year, validating H₂ compatibility with existing infrastructure.^[3]
2. Köln Green Hydrogen Project (Germany):
   • Scope: 100MW Hydraeon electrolyser producing green H₂ for ammonia and e-methanol synthesis.
   • Impact: Expected to cut 120,000 tonnes CO₂/year by 2026.^[3][7]

Strategic Roadmap

• 2025: Scale Köln project to 100MW, integrating carbon capture for e-methanol.^[3][7]
• 2030: Deploy GW-scale Hydraeon plants across Europe, targeting 1 million tonnes H₂/year.^[1][4]

References

1. INEOS Group > Businesses > INEOS Electrochemical Solutions > 8^th May 2025, Hydraeon Alkaline Water Electrolyser brochure.
2. INEOS Group > News, 25^th Feb 2021, A first in Belgium: INEOS Phenol and ENGIE use hydrogen in industrial plant in Antwerp.
3. Sanja Pekic, 21^st Oct 2021, INEOS to produce green hydrogen in Germany,OFFSHORE ENERGY. 
4. INEOS Group > Businesses > INEOS Electrochemical Solutions > Hydraeon Alkaline Water Electrolyser. (Accessed 23^rd May 2025)
5. 13th Julk 2021, Going green with hydrogen at INEOS Phenol: first test pilot project successful, EQUANS.
6. Callum O'Reilly, 3^rd Mar 2021, INEOS and ENGIE launch hydrogen pilot project, HYDROCARBON ENGINEERING.
7. Ahlam Rais, 23^th Oct 2021, Ineos’ Green Hydrogen Project to Build 100 MW Electrolyzer, PROCESS WORLDWIDE.