Emulsified Oil Removal Above 95%: The SINOKLE KHC Coalescing Oil Separator Leads a New Breakthrough in Physical Demulsification
In the petrochemical, power and energy industries, oily wastewater treatment is an environmental issue that simply cannot be avoided. From oilfield produced water to refining unit effluent, from power plant desulfurization wastewater to tank-farm cut water, oily wastewater of every kind is present throughout industrial production.
Yet the hardest fraction to treat is not the "free oil" that separates easily, but the highly emulsified "emulsified oil". Emulsified oil is dispersed in water as tiny droplets, typically only a few microns across or less. Because surfactants are present, these droplets can remain stably suspended in the water for a very long time without rising naturally. Conventional methods such as gravity settling and oil-intercepting ponds are nearly helpless against emulsified oil.
Statistics show that the petrochemical, power and other industries in China generate several billion tons of emulsified-oil wastewater every year. Poorly handled, it causes severe environmental pollution and also wastes a valuable petroleum resource.
Emulsified oil is difficult to treat mainly for the following reasons:
First, the droplets are extremely small. Emulsified oil droplets typically measure 0.1-10 microns in diameter, tens to hundreds of times smaller than free oil. Conventional flotation equipment produces bubbles of roughly 50-100 microns, which struggle to capture such fine droplets effectively.
Second, stability is high. The surface of emulsified oil is wrapped in surfactants, forming a stable "water-in-oil" or "oil-in-water" structure. Just like milk, the oil and water have become a single phase, and ordinary physical methods can hardly separate them.
Third, the composition is complex. Emulsified wastewater contains not only oily substances but also large amounts of suspended solids, silt and chemical additives, adding further difficulty to treatment.
In the past, the industry generally used chemical demulsification to treat emulsified oil — dosing a demulsifier so the emulsion "breaks" and oil separates from water. But this approach requires continuous chemical dosing, carries high operating costs, and may cause secondary pollution.
Chemical demulsification is currently the most widely applied technical route, but it has plenty of problems:
High reagent cost: demulsifiers must be purchased and dosed continuously, and the expense accumulates
Large sludge volumes: the chemical reaction produces large amounts of oily sludge that is difficult to dispose of
Unstable performance: when water quality fluctuates, treatment results fluctuate with it
Secondary pollution: residual chemical reagents may create new pollution problems
Is there a way to remove emulsified oil efficiently without chemical reagents? SINOKLE has the answer — the KHC coalescing oil-water separator.
This equipment achieves highly efficient removal of emulsified oil by purely physical means, relying on specially modified super-oleophilic, hydrophobic coalescing fiber material.
The core technology of the KHC coalescing oil separator involves four synergistic mechanisms:
1. Cyclonic centrifugal separation: centrifugal force performs a preliminary oil-water separation and removes most of the free oil
2. Wetting coalescence: as emulsified oil passes through the coalescing material, droplets are captured by the fiber surface and gradually coalesce into large oil beads
3. Collision coalescence: droplets collide with one another as they pass through the filter bed and merge into still larger droplets
4. Interception filtration: finally, fine filtration intercepts the remaining tiny oil droplets and suspended solids
After these four "checkpoints", emulsified oil is removed efficiently and the clean water can be discharged in compliance.
Compared with conventional chemical demulsification, the KHC coalescing oil separator offers clear advantages:
1. High removal efficiency: it removes emulsified oil with droplet sizes above 0.1 micron, with an oil removal rate exceeding 95%. That means even highly emulsified wastewater can be treated to a very high standard.
2. Short residence time: wastewater needs less than 3 minutes inside the unit, giving high treatment efficiency and a small footprint.
3. Strong tolerance to impurities: the unit removes suspended solids at the same time, adapts to a wide range of complex water qualities, and is not prone to clogging.
4. Long filter element life: the modular element design makes replacement simple and quick. Coalescing elements last 2-5 times longer than conventional products.
5. No chemical reagents: it works on a purely physical principle with no chemical addition whatsoever, eliminating secondary pollution at the source.
6. Low operating cost: no continuous reagent purchases are needed, so long-term operating costs are significantly lower than with chemical methods.
Typical Case
At a back-pressure cogeneration project in Shaanxi, the power plant produced oily wastewater with an oil content as high as 500,000 ppm (about 50%), making treatment extremely difficult. SINOKLE applied a combined "pre-filter + KHC coalescing oil separator" process, and the final effluent oil content dropped below 5 ppm — a removal rate above 99%, far beyond the discharge standard.
As environmental requirements grow stricter, physical oil-removal technology is becoming a new industry trend. Centered on technological innovation, the KHC coalescing oil separator offers an efficient, economical and environmentally sound new option for emulsified oily wastewater treatment.
