How SINOKLE CDFU Cyclonic Flotation and KFM Filtration Work Together on Oily Wastewater
Background and Challenges
In power plant operation, heavy oil tank farms generate oily wastewater. Its composition is complex and it contains large amounts of emulsified oil and suspended solids that conventional treatment struggles to separate. Emulsified oil droplets are fine and very stable, so gravity settling cannot remove them, while suspended solids make treatment harder still. Discharging such water untreated causes environmental pollution, pipeline blockage and equipment corrosion.
Innovative Process Design
To solve this problem, SINOKLE proposed a pretreatment solution built around CDFU cyclonic dissolved air flotation units and KFM active filter media filtration units as the core.
Figure: Process flow of oily wastewater pretreatment at a heavy oil tank farm of a power plant
CDFU cyclonic dissolved air flotation explained
CDFU units combine ultra-fine bubble generation, dissolved air flotation and cyclonic separation. The working principle involves three key steps:
Dissolved air water preparation: air dissolves in water under pressure to form saturated dissolved-air water
Micro-bubble release: when the pressure drops, the dissolved-air water releases large numbers of 5–30 μm micro-bubbles
Efficient separation: after the wastewater mixes with the micro-bubbles, the bubbles attach to oil droplets and suspended solids to form flotation agglomerates that migrate to the centre under cyclonic centrifugal force
A single stage removes more than 90% of oil and over 85% of suspended solids, significantly improving separation efficiency.
KFM active filter media filtration
KFM units use a special active filter medium and achieve deep purification through several mechanisms:
Adsorption: the filter surface adsorbs residual oil
Interception: fine suspended solids are physically trapped
Filtration: the water is polished further
Figure: Oily wastewater treatment unit at a heavy-oil power plant in Bangladesh
