How the High-Efficiency Coalescing Oil Separator Works: Fast Coalescence and Separation of Oil Droplets
The coalescing pressure-type oil separator is a high-efficiency oil-water separation device. It combines the coarse-granulation principle and the shallow-pool principle with CFD simulation to optimise the internal structure and flow-field layout of the vessel, achieving rapid aggregation, coalescence, flotation (or settling) and separation of oil droplets or suspended solids in water.
Working principle diagram of the coalescing pressure oil separator
Its core workflow is as follows:
1. Inlet pre-separation: oily wastewater enters the unit tangentially through a specially designed cyclonic separator. Under the strong centrifugal force, dispersed oil is separated quickly and preliminarily, while the device also dissipates energy, distributes the flow evenly and removes sand.
2. Coalescence and growth: the flow then enters the primary and main separation zones, which are packed with proprietary coalescing media. These media have a super-hydrophilic modified surface and a huge specific surface area, effectively capturing fine oil droplets (down to 0.1 µm) so that droplets move along the fibres, collide and coalesce under the flow, gradually growing into larger droplets.
3. Oil-water separation: under the shallow-pool principle, the enlarged droplets rise rapidly and collect in the oil-collection box at the top of the vessel, while the treated clean water is discharged from the bottom. A special sand-flushing system at the bottom effectively prevents sediment accumulation, ensuring long-term stable operation.
The unit operates fully enclosed, pressurised and automatically, with the liquid level precisely controlled by a PLC system. It features a compact structure, high oil removal efficiency (>90%), strong shock resistance, no chemical dosing and no secondary pollution.
Thanks to its efficient separation and stable operation, the coalescing pressure-type oil separator has been successfully applied in many industrial fields.
High-emulsification wastewater treatment in the petrochemical industry
In the Sinopec Cangzhou Branch desalter effluent treatment project, a coalescing pressure oil separator + CDFU combination process is used, with a single train capacity of 1,200 m³/d. The unit successfully reduced influent oil content from 20,000 mg/L to 35 mg/L, with oil removal efficiency above 99%, and the recovered oil is of good quality and can be refined directly.
