Refinery Wastewater Treatment Process
As a key pillar of the national economy, the refining industry faces oily wastewater treatment as a constant environmental priority. Modern refinery wastewater is complex in composition, high in pollutant concentration and rich in refractory organics, so conventional processes often struggle with low efficiency, serious secondary pollution and high operating costs.
Technical breakthrough: CDFU Cyclonic dissolved-air flotation unit
Developed by SINOKLE Technology, the CDFU cyclonic dissolved-air flotation unit integrates internationally leading cyclonic centrifugal separation, dissolved-air flotation separation and ultra-fine bubble technologies, providing a revolutionary solution for refinery wastewater treatment.
CDFU Schematic diagram of the cyclonic dissolved-air flotation workflow
The core advantage of this technology lies in its ultra-fine bubble generation system, which produces bubbles of 5-30 μm that are evenly dispersed and highly adsorptive. Compared with conventional processes, CDFU the unit achieves single-stage oil removal efficiency above 90% and suspended solids removal above 85%, with effluent oil content reduced to below 5 mg/L, meeting high-standard discharge requirements.
Process features and innovative advantages
Fast, high-efficiency treatment: CDFU the unit's residence time is only 1-5 minutes, 3-8 times the efficiency of conventional flotation, with a maximum single-unit capacity of 500 m³/h.
Green, environmentally friendly process: purely physical demulsification with no chemical dosing fundamentally eliminates oily sludge generation and greatly reduces the risk of secondary pollution.
Compact, intelligent design: the skid-mounted structure requires only one third of the footprint of conventional equipment, making it especially suitable for space-constrained refineries. Integrated IoT and AI monitoring systems enable real-time water-quality monitoring and remote unattended operation.
Engineering practice and application results
In the Sinopec Cangzhou Petrochemical electro-desalter wastewater treatment project, CDFU technology successfully reduced oil content from 20,000 mg/L to 35 mg/L, and the recovered oil is of good quality and can be refined directly. The PetroChina Sichuan Petrochemical tank-farm wastewater treatment project also verified the stability and efficiency of the technology.
For harder-to-treat wastewater such as coking acidic water, the "coalescer + CDFU combination process shows strong adaptability. Operating data from the Sinopec Luoyang Petrochemical project show oil content falling from 15,000 mg/L to 98 mg/L and suspended solids from 500 mg/L to 8.2 mg/L.
Comparative technical advantages
Compared with conventional technologies, CDFU it shows significant advantages in key indicators such as bubble diameter (5-30 μm), oil removal efficiency (>90%) and residence time (<5 min). Its enclosed operation and automatic control ensure stability and safety throughout the treatment process.
Future outlook
Driven by the "dual carbon" goals, refinery wastewater treatment is moving towards green, low-carbon and circular development. CDFU technology-based pure physical treatment solutions not only avoid the use of chemicals and reduce carbon emissions, but also achieve resource recycling through oil recovery. In the future, with the deep integration of new materials and big data, refinery wastewater treatment will become more efficient, intelligent and environmentally friendly.
SINOKLE's CDFU technology, with its innovation and practicality, provides strong technical support for the green transition of the refining industry and has achieved remarkable results in several large refining and petrochemical projects at home and abroad, showing broad application prospects.
