Tertiary Vapor Recovery Device for Gas Station Tank Breathing Emission｜Vohon Petrochemical
The tertiary vapor recovery device is designed to handle tank breathing volatile emission from gasoline storage tanks at gas stations. During fuel filling and daily temperature variation, gasoline tanks generate a large volume of oil‑gas mixture. Without proper treatment, tank breathing vapor will be directly released into atmosphere, resulting in fuel loss, air pollution and potential fire risk. This unit adopts combined compression‑condensation and membrane separation physical process, achieving vapor recovery instead of simple destruction of hydrocarbon components.
Oil‑gas mixture discharged from tank breathing ports is collected through closed pipeline and delivered into the system. A buffer module is equipped to stabilize fluctuating pressure and flow rate caused by tank breathing. Pre‑treatment section removes liquid droplets and impurities carried in oil‑gas, protecting core components including compressor, condenser and membrane modules from contamination and corrosion.
After compression, hydrocarbon vapor rises in partial pressure and enters multi‑stage condensation unit. Most gasoline components are liquefied under controlled cooling condition. Recovered liquid gasoline can flow back to underground storage tanks for reuse. The non‑condensable mixed gas then flows toward membrane separation assembly. Through selective permeation property of polymer membrane, hydrocarbon molecules are concentrated on the permeate side, while cleaned gas passes through and meets local emission standards. The concentrated high‑concentration oil‑gas stream circulates back to the front‑end compression section for secondary recovery, improving overall oil‑gas recovery efficiency.
The whole set of equipment follows explosion‑proof design for petrochemical sites. All electrical components comply with hazardous area requirements. Integrated safety interlocks cover over‑pressure, over‑temperature and abnormal liquid level conditions. Emergency vent bypass is reserved to cope with unexpected working conditions and guarantee station operation safety. Local on‑site monitoring interface supports real‑time observation of pressure, temperature and running status, and can realize signal interconnection with station control system.
This tertiary vapor recovery unit is suitable for newly‑built gas stations as well as reconstruction projects of existing fuel stations. Compact skid‑mounted structure minimizes site occupation, facilitating transportation, installation and commissioning. It effectively reduces gasoline loss caused by tank breathing emission, helps gas stations satisfy environmental supervision requirements, and realizes resource recycling of volatile oil‑gas.