Three‑stage oil‑gas recovery device serves as the core terminal processing equipment for filling station vapor control systems, working cooperatively with primary and secondary vapor recovery systems. It handles hydrocarbon vapors generated from tank breathing, temperature fluctuation and pressure variation inside underground fuel storage tanks. When tank internal pressure exceeds preset thresholds, the unit automatically starts to capture excessive gasoline vapors, cutting fuel loss, lowering VOC emissions, eliminating flammable vapor accumulation risks and helping gas stations satisfy local environmental compliance requirements.
Conventional treatment methods bring obvious drawbacks. Direct venting leads to massive fuel waste and safety hazards. Single activated‑carbon adsorption suffers from frequent saturation under variable vapor loads, generates large‑volume hazardous waste and demands high‑frequency replacement of consumables. Simple condensation technology struggles to maintain stable recovery efficiency facing fluctuating vapor concentration from tank breathing cycles.
Adopting compression‑condensation‑membrane coupling all‑physical process, the three‑stage oil‑gas recovery device achieves vapor liquefaction and recycling without combustion or chemical reaction. Tank‑breathing vapors are collected via closed pipelines and delivered to buffer assembly to stabilize pressure fluctuation triggered by temperature change. Multi‑stage pre‑treatment removes liquid droplets and fine aerosols, protecting compressors, heat exchangers and membrane elements against fouling and corrosion. After compression for partial‑pressure elevation, most hydrocarbon components turn into liquid gasoline through gradient multi‑stage cooling. Residual low‑concentration vapors flow into membrane separation module for selective enrichment. Purified air meets emission standards, while concentrated vapor stream circulates back for repeated processing to raise overall recovery performance. Recovered liquid gasoline flows back to underground storage tanks for direct reuse, bringing tangible economic benefits to station operators.
The whole unit complies with ATEX explosion‑proof specifications for hazardous fuel sites. It is fitted with over‑temperature, over‑pressure, combustible‑gas detection interlock and emergency vent bypass to cope with abnormal working conditions. Intelligent variable‑frequency control adjusts operation status according to real‑time tank pressure and vapor load, enabling automatic start‑stop and long‑term unattended running. Compact structural layout saves floor space, suitable for newly‑built gas‑station construction and old‑site renovation upgrade projects. Customization on processing capacity and internal configuration is available to match different‑scale filling‑station working conditions. It delivers a reliable solution for global petrol stations to realize emission compliance, fuel recycling and site safety management simultaneously.