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The Technology

What is hydrothermal oxidation?

Hydrothermal oxidation is any technology that treats waste by oxidation reactions in elevated temperature water. Using higher temperatures, SCFI offers a suite of technologies offering better performance than traditional Wet Air Oxidation (WAO).

Water Properties
As the temperature of water rises, its properties change. Near 374 °C and 221 bar, water becomes supercritical, and its properties change drastically, but water properties begin to change even before that.
TemperaturePressureIceSteamLiquidSupercriticalWaterCriticalPointTriplePoint374 °C221 barLowTemperatureWAONear-criticalNCSupercriticalSCWO
What's Inside?
Low-pressure (WAO)
Properties:

At low temperatures, oxidant and water are distinct phases with limited solubility.

Reactions are slower because they are limited by mass transfer from the gas phase to the liquid phase. Residence times of hours are necessary.

Suitable for:

Easy-to-treat wastes, caustic containing sodium sulphide.

Near-Critical (NC)
Properties:

As water reaches 300 °C, it behaves as an alcohol-like solvent that can readily dissolve hard-to-treat compounds such as mercapatans and benzene.

Near-critical oxidation can obtain COD destruction greater than 90-95% for organic compounds. Residence times of minutes are typical.

Suitable for:

Organic and recalcitrant compounds.

Supercritical (SCWO)
Properties:

Supercritical water oxidation will treat any organic matter with destruction greater than 99% and residence times of seconds.

SCFI has been developing SCWO since the company's inception. SCWO is a game changer in waste treatment.

Suitable for:

Any organic or inorganic waste with high energy content or high disposal cost.

The Smarter Choice

Why Choose AquaCritox®?

image/svg+xmlWasteOxidantCleanEffluent
Better performance
  • High contaminant destructions up to 99.99+%
  • Clean effluent ready for reuse or conventional water treatment
  • Lower energy consumption and cost than Wet Air Oxidation or Incineration
Sustainability
  • Meet increasingly strict discharge limits
  • No harmful off-gas generation
  • Permanent contaminant destruction — Doesn’t just move waste from one stream to another
  • Treat the toughest wastewaters: spent caustic, organic solvents and acids, PFAS, sludge, and many more…

SCFI's HTO Technologies

Specialist AquaCritox Technologies

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