CDFU + Fine Filtration: The Efficient Treatment Process for High-Oil Sour Water Revealed
2026-11-12 10:59:36
Sulphur and nitrogen compounds are widespread in petroleum and its derivative products. In petroleum processing flows such as atmospheric-vacuum distillation, catalytic cracking, delayed coking and catalytic hydrogenation, these compounds undergo high-temperature pyrolysis, catalytic cracking, hydrocracking and other reactions, converting into H₂S and NH₃-N. Subsequent condensation-dewatering or water washing produces sulphur- and ammonia-bearing wastewater, commonly known in the industry as sour water. High-oil sour water specifically refers to such wastewater whose oil content is abundant and whose oil and acid concentrations are markedly higher than normal. If discharged without treatment, it would severely damage the ecological environment and must be professionally treated to meet discharge standards.
High-oil sour water has unique water quality characteristics: the water is rich in high concentrations of oils, acidic substances and suspended particles. These make the water turbid and pungent; if discharged directly, it would threaten the balance of the aquatic ecosystem and also seriously endanger human health and safety.
Treating high-oil sour water faces many challenges. This wastewater has a high coke-powder content with fine particle size, a persistently high oil content, prominent emulsified oil problems, and contains large amounts of sulphides, ammonia nitrogen and phenols; the pollutants are complex and diverse, and concentrations fluctuate frequently. These complex water quality conditions mean the treatment process requires large amounts of money and resources, driving treatment costs up sharply.
At present, treatment of high-oil sour water mainly uses three categories: physical, chemical and biological. Physical means include settling, filtration and adsorption, which can effectively separate suspended impurities and oils from the water; chemical treatment uses chemical reagents, purifying the water through neutralisation, oxidation and other reactions; biological treatment relies on microorganisms to degrade organic matter. However, each has pros and cons: physical methods are simple to operate but limited in efficiency; chemical methods are efficient but may cause secondary pollution; biological methods effectively degrade organic matter but impose strict requirements on water quality.
To conquer the treatment difficulty of high-oil sour water, our company has developed, based on patented technology, a process centred on the CDFU (high-efficiency compact cyclonic flotation), fine filtration and the KHC high-efficiency coalescing separator as core equipment. The unit can precisely remove emulsified oil with droplets as small as 0.1 μm, keeping the effluent oil content stably below 10 ppm — a technology level at the international forefront. Compared with conventional processes, the new technology offers both significant environmental and economic benefits.
Emulsified sour water treatment process flow diagram
In short, the treatment of high-oil sour water is constantly developing and improving, and the continuous emergence of new technologies brings new breakthroughs to the field. Looking ahead, with environmental awareness taking root and technology advancing, the treatment of high-oil sour water will surely move toward greater efficiency and environmental friendliness.
On-site view of an oily sour water treatment case
