Case Study: Treating Oily Wastewater at a Tianjin Heavy Industry Maintenance Workshop

Background: Sources and Challenges of Oil-Bearing Wastewater

 In heavy industry maintenance workshops, oily wastewater is generated primarily from equipment lubricant leaks, machining coolants, and parts-washing solutions. These substances mix with water to form a complex wastewater containing free oil, emulsified oil, and trace amounts of dissolved oil. If discharged directly, this wastewater not only contaminates surrounding soil and water bodies but can also clog pipelines and disrupt the normal operation of wastewater treatment plants. A heavy industry company in Tianjin generates a substantial volume of oil-bearing wastewater daily in its maintenance workshop; however, traditional sedimentation and oil-skimming methods struggle to efficiently separate emulsified oils, resulting in low treatment efficiency and high operational and maintenance costs.

Solution: Application of the Brator Horizontal Oil-Water Separator

To solve this problem, the facility installed Brator's WYS Horizontal Oil-Water Separator as the centerpiece of its treatment system. Key advantages include:

High-Efficiency Separation Capability:

Utilizing physical sedimentation and coalescence technologies, the Horizontal Oil-Water Separator effectively separates free oils and a portion of the emulsified oils present in the wastewater. Its optimized internal structural design ensures uniform water flow distribution, allowing oil droplets to rapidly rise to the oil collection trough while suspended solids settle to the bottom, thereby achieving a three-phase separation of oil, water, and sludge.

Compatibility with Multi-Stage Treatment Processes:

The Horizontal Oil-Water Separator can be integrated with other units—such as bar screens, equalization tanks, and air flotation equipment—to form a synergistic wastewater treatment system. The wastewater first passes through bar screens to remove large particulate impurities, then enters an equalization tank to homogenize flow and concentration, before undergoing primary oil separation in the Horizontal Oil-Water Separator. Subsequent stages, combining flocculation reactions with dissolved air flotation, further remove residual emulsified oils and suspended solids, resulting in a significant improvement in the quality of the final effluent.

Automation and Energy-Efficient Design:

The equipment operates without the need for external chemical additives, thereby minimizing the risk of secondary pollution. Its compact horizontal configuration requires minimal floor space, making it well-suited for workshop environments with limited spatial availability. Furthermore, the system features an intelligent control interface that enables automated oil and sludge discharge, effectively reducing manual labor requirements and operational costs.

Application Results: A Win-Win for Both the Environment and the Economy

Oil Recovery and Water Purification:

The removal rate for petroleum-based substances in the treated wastewater reaches 99%. The separated oil can be recovered for use as industrial fuel or as a raw material for recycled lubricants, thereby achieving effective resource recycling.

Dual Compliance: Emission Reduction and Regulatory Standards:

The treated water can be utilized for on-site landscaping, floor washing, or within circulating cooling systems, significantly reducing the consumption of fresh water. Discharged wastewater meets the *Emission Standard of Pollutants for Petroleum Refining Industry* (GB 31570-2015), thereby effectively mitigating environmental risks.

Significant Economic Benefits:

Taking this specific project as an example, nearly 100 tons of waste oil can be recovered annually. This results in a reduction of over 30% in outsourced wastewater treatment costs, with a payback period for the equipment investment of less than two years.

Conclusion：

A heavy industry company in Tianjin successfully resolved the challenge of treating oil-bearing wastewater in its maintenance workshop through the application of Brator horizontal oil-water separators. This technology not only achieves effective separation of oil and water but also generates revenue through resource recovery while simultaneously lowering pollution control costs, serving as a model for the practice of "green manufacturing" within the heavy industry sector.