Oxygen & Hydrogen Ecosystem Trials
Client: Northern Ireland Water
Value: £4.4m
Northern Ireland Water appointed Lagan MEICA to design, build and operate a demonstrator plant at Belfast Wastewater Treatment Works (WwTW). The main aim of the project was to evaluate the performance of a hybrid system which introduces a blend of pure oxygen and air into the existing air delivery system of the secondary wastewater treatment process. Lagan MEICA, as the principal contractor and designer, are responsible for the overall design and integration of the plant which consists of three main parts:
A 1MW Membrane-Free Electrolyser with cryogenic separation that delivers pure hydrogen and oxygen as separate gases.
Hydrogen and Oxygen compression and storage unit.
Two Sequential Batch Reactors (SBRs).
Liquid Oxygen Trial Results
Due to delays in the delivery of the electrolyser, we used liquid oxygen to demonstrate the advantages of a blended oxygen supply for wastewater treatment. The results are:
Increased headroom & treatment capacity (secondary treatment)
Reduce treatment time by 15%.
Increase specific nitrification rate by 31%.
Reduced energy consumption, carbon footprint & cost
Reduce blower energy consumption per batch by 13%.
Reduce surplus activated sludge (SAS) production, transportation & disposal by 6%.
This demonstrator project is the third phase investigating green hydrogen and oxygen electrolysis following a prior successful proof-of-concept, and oxygen trial at Kinnegar WwTW as part of NI Waters SBRI Energy Storage Opportunities Project.
Project Update
March 2025
A CPH2 electrolyser (Derated) has been installed in Belfast and is currently being commissioned. We expect to be producing hydrogen in early May 2025. A 1mw electrolyser should follow in the autumn of 2025 along with both Hydrogen and Oxygen compression equipment.
