Treating Oily, Acidic Wastewater: Advanced Oil-Water Separation for the Biofuel Industry

In the field of biomass resource conversion and utilization, the production of biodiesel and bio-aviation kerosene from oils has become an important direction for green energy development. In a 500,000-ton/year industrial-grade oil-to-biodiesel and bio-aviation kerosene project, oily, acidic wastewater is generated during key stages such as feedstock pretreatment, esterification, and product refining. The oil fraction derives primarily from unreacted feedstocks, intermediates, and byproducts. Its composition is complex, including free fatty acids, triglycerides, and emulsified oils. Furthermore, due to the use of acidic catalysts in the process, the wastewater is highly acidic (pH as low as 2-4). Conventional methods are often ineffective at separating these micron-sized droplets, leading to elevated oil content that hinders water reuse and poses significant compliance risks.

Technological Breakthrough: Synergistic Effect of Multi-Stage Coalescing and Patented Coating

Brator's WYS horizontal oil-water separator employs a four-stage oil removal process—cyclonic separation, coarse coalescence, polymer coalescence, and corrugated plate coalescence—creating a progressive capture system for oil droplets of varying sizes. Its core innovations are:

1. Cyclonic Pre-Separation: Utilizing centrifugal force to rapidly remove free oil droplets with a diameter >50μm, reducing the load on subsequent processing;

2. Multi-Stage Coalescing Enhancement: Coarse-grained packing aggregates and enlarges 10-50μm oil droplets, while the polymer coalescence layer further captures 20-30μm micro-droplets, and the corrugated plate structure achieves final interception of oil droplets larger than 10μm;

3. Patented Corrosion-Resistant Coating: The inner wall of the equipment uses a special polymer composite coating that combines resistance to acid and alkali corrosion with oleophilic and hydrophobic properties, maintaining high-efficiency separation performance even in strongly acidic environments, extending its service life to more than three times that of traditional equipment.

Performance Verification: A Leap from 1000ppm to 100ppm

Project test data shows that after treatment by the WYS separator, the total oil content of wastewater decreased from an initial 1000ppm to below 100ppm, far below the national emission standard (≤150ppm). Compared to single-technology equipment, its oil droplet removal rate is improved by 40%, especially for emulsified oil below 20μm, achieving a retention efficiency of over 92%, breaking through the "micro-oil droplet removal bottleneck" of traditional processes.

Industry Value: Full-Process Resource Utilization and Environmental Closed Loop

The system enables continuous three-phase separation: recovered oil can be processed into valuable byproducts like crude fatty acids; solids are periodically discharged and can be further treated for resource recovery; and the clarified water is suitable for direct reuse in cooling or washing operations. This model not only improves the utilization rate of oil raw materials (reducing raw material loss by 3%), but also reduces the amount of oily sludge generated by more than 50%, significantly alleviating the pressure on end-of-pipe water treatment. Its modular design allows for seamless integration with existing processes, providing a low-cost, high-efficiency environmentally friendly solution for the biomass oil production industry and contributing to the sustainable development of the green energy industry under the "dual carbon" target.