Systems / Water deaeration
Water deaeration
The Minox®Compact Systems (two-stage) is based on gas stripping of seawater with co-current contact through static mixers in a two-stage system. The stripping gas is nitrogen, regenerated through a catalytic reactor and circulated by an eductor in a closed loop.
Choose your system
Deaeration configuration
[01]
Minox™ Two-stage
Two stages through static mixers, with the nitrogen regenerated in a closed loop. The fifth generation replaces the compressor with a liquid jet compressor. See if we can fit in Low OPEX
[02]
Minox™ Tower
The Tower and complete water injection plants built around it. Field-proven hardware that takes the oxygen out of injection water without scavenger chemicals.
[03]
Membrane
Membrane contactors remove dissolved gases and suit low flow rates. With the Minox nitrogen regenerator, up to 30% fewer contactors are needed.
[04]
Complete water injection packages
Complete systems for floating and fixed facilities, delivered as EPCIC with every interface and deliverable integrated.
How it works
Oxygen out, no scavenger chemicals
The Tower strips the water with nitrogen in one vessel. Nitrogen and water meet in counter-current flow over structured packing, and the nitrogen is cleaned and used again in a closed loop.
It runs at atmospheric or positive pressure, and it replaces vacuum and fuel gas deaerators. Existing towers can be converted.
Containerised & mobile
Built to move
Skid-mounted units, tailor-made to fit a given space. The fifth-generation test system is built inside a container, so it can be shipped and pilot-tested on site.
[01]
Transport mode
[02]
Operational mode
Why Minox for FPSO
Built for FPSOs
Complete water injection deaeration for FPSOs, from compact membrane systems to large tower-based systems and full water injection packages.
Closed cooling loops
A compact Minox skid on a side stream keeps dissolved oxygen in closed cooling and heating loops below 5 ppb, without oxygen scavengers and with no rotating equipment.
A fully electrified standard design:
Easy hook-up and installation
Self-contained, all utilities on skid
Stand-alone or integrated control
No rotating equipment
Dissolved oxygen < 5 ppb
Filtration < 1 µm (optional)
Minox standard water system deoxygenation skid.
From challenge to operation
[01]
Challenge
Oxygen enters with make-up water and air ingress. It drives corrosion, microbial growth and biofilm, fouls heat exchangers and raises maintenance and chemical costs.
[02]
Solution
Treat a side stream of the loop through the Minox deoxygenation process. Nitrogen strips the oxygen in a closed gas loop that is regenerated catalytically, so no chemicals are added to the water.
[03]
Operation
The standard design runs intermittently, starting only when the water is off spec. A once-through design is field proven up to 5,000 m³/h for larger flows.
District energy
Process cooling
Data centre cooling
Power & CHP plants
Chilled-water systems
Complete plants
Complete water injection plants
Minox delivers complete water injection systems for floating and fixed facilities, built around the Tower. We work with the operator from the early phase, so the plant is robust from the start.
As a complete EPCIC provider, Minox integrates every interface and deliverable. That optimises lead time, cost and injection water quality.
Reference list
Installed base - Minox Deoxygenation Systems
Reference list
Pilots & Studies
FAQ · Technical Background
Does CO₂ from the Minox process affect the seawater?
[01]
CO₂ in seawater
Air holds ~330 ppm CO₂. Seawater holds ~90 ppm dissolved CO₂, against only ~7 ppm O₂. Cold, less saline, high-pressure water holds more gas.
CO₂ is over 10× more soluble than O₂ because it reacts with water:
CO₂(aq) + H₂O ⇌ H₂CO₃
H₂CO₃ ⇌ HCO₃⁻ + H⁺
HCO₃⁻ ⇌ CO₃²⁻ + H⁺
CO₂(aq) + H₂CO₃
~1%
Bicarbonate, HCO₃⁻
~93%
Carbonate, CO₃²⁻
~6%
[02]
Where the CO₂ comes from
Nitrogen strips dissolved O₂ from the water. The O₂ is then burnt over a catalyst with a fuel:
Hydrogen
2H₂ + O₂ → 2H₂O
Natural gas (methane)
CH₄ + 2O₂ → CO₂ + 2H₂O
Methanol
2CH₃OH + 3O₂ → 2CO₂ + 4H₂O
Ethanol
C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O
Hydrogen gives only water vapour. With carbon fuels, CO₂ joins the stripping gas and part of it dissolves.
[03]
Why the impact is small
CO₂ can only form from the O₂ removed. Maximum CO₂ from 7 ppm O₂:
Hydrogen
0 ppm
Natural gas
≈ 4.8 ppm
Methanol, ethanol
≈ 6.4 ppm
Field measurements (2008): +5–20 ppm, against ~90 ppm already dissolved.
~99% of dissolved carbon is HCO₃⁻ and CO₃²⁻, which buffer seawater at its natural pH of 7.5–8.5.
Net effect: O₂, the main driver of corrosion, is removed. The CO₂ added is small.
Source: Minox Technology technical paper, 2008. Maximum CO₂ = 7 mg/L O₂ ÷ 32 g/mol × CO₂:O₂ mole ratio × 44 g/mol.
Qualification
Qualify a large system
Tell us the field, the capacity and the timeline. This form moves into the login later.