VRU Vapor Recovery Unit for Gas Station Oil‑Gas Treatment | Vohon Petrochemical Manufacturer
VRU vapor recovery unit is a dedicated physical recovery system designed for gasoline vapor emission control at fuel filling stations, mainly handling volatile hydrocarbon vapor generated during tank truck unloading, vehicle refueling and storage tank breathing processes. Gas station oil‑gas emissions feature obvious intermittent and pulse‑release characteristics. Large‑volume vapor escapes during tanker off‑loading, while refueling operations produce continuous low‑concentration vapor discharge. Vapor volume and concentration change greatly under different working conditions. Gasoline vapor contains light hydrocarbon components, which are flammable and explosive. Therefore, the VRU system demands high‑level explosion‑proof configuration, reliable anti‑liquid‑entrainment pretreatment, wide‑condition adaptability and stable long‑term operation performance.
Traditional gasoline vapor disposal solutions have inherent drawbacks when applied to gas station scenarios. Direct incineration completely destroys recoverable hydrocarbon vapor and brings substantial resource waste. Combustion also generates nitrogen oxides and other combustion by‑products, requiring extra supporting facilities and raising overall investment and operating expenditure. Activated carbon adsorption is a pollutant‑transfer method rather than resource‑oriented recovery. Frequent adsorption‑desorption cycles under pulse vapor impact make adsorbent easy to saturate and degrade. Liquid gasoline entrainment will cause carbon bed agglomeration, bringing hidden risks of heat accumulation. Frequent replacement of adsorption consumables produces large amounts of hazardous waste and increases daily operation burdens for station operators. Simple single‑stage condensation equipment only delivers acceptable recovery effect under high‑concentration peak vapor conditions. When vapor concentration drops, partial hydrocarbon components cannot be liquefied effectively, leading to excessive hydrocarbon emission in tail gas and failing to meet regulatory discharge requirements. Single‑process equipment cannot satisfy full‑cycle stable treatment for gas station complex variable working conditions.
Adopting compression‑condensation‑membrane coupling full‑physical process without combustion or chemical reaction, the VRU vapor recovery unit is highly suitable for gas station oil‑gas treatment. Oil‑gas vapor produced during tanker unloading, tank breathing and vehicle refueling is collected through closed pipeline system. Buffer module is equipped to stabilize sharp fluctuation of gas pressure and flow rate. Incoming vapor first passes through multi‑stage pretreatment unit to remove entrained liquid oil droplets and free moisture layer by layer, preventing liquid carry‑over from entering compressors, heat exchangers and membrane assemblies, avoiding component fouling, blockage and irreversible membrane contamination. Hierarchical interception structure protects core precision parts and extends the service life of whole unit.
After pretreatment, oil‑gas vapor goes into compression unit to raise partial pressure of hydrocarbon vapor and adjust gas‑liquid equilibrium state for liquefaction. Multi‑stage gradient condensation module cools down the mixed vapor according to different boiling points of light hydrocarbon fractions, and most gasoline components are liquefied and separated to finish primary oil‑gas recovery.
Tail gas still contains residual uncondensed hydrocarbon components and flows into organic membrane separation module. Based on different permeation rates between hydrocarbon molecules and air molecules, organic vapor is highly enriched. Tail gas after treatment meets emission requirements and is discharged. High‑concentration hydrocarbon‑rich stream from membrane side circulates back to compressor inlet, forming closed‑loop circulation and further improving comprehensive recovery efficiency of gasoline vapor. Recovered liquid gasoline can be returned to underground storage tank for reuse, cutting resource loss caused by oil‑gas volatilization and bringing direct economic benefits for gas stations.
The unit adopts integrated skid‑mounted structure, completing factory assembly, explosion‑proof inspection and pressure test before delivery. Compact footprint reduces site construction workload. It can connect with existing gas station vapor collection pipelines, minimizing reconstruction scope and shortening project implementation cycle with little interference to daily station business.
All electrical instruments and motors comply with gas station explosion‑proof standards. Pipelines, valves and heat‑exchange components contacting oil‑gas medium are made of high‑strength anti‑corrosion materials. Complete interlock protection for over‑pressure, over‑temperature and flammable gas detection is configured together with emergency vent bypass to cope with instant high‑concentration vapor pulse during tanker unloading, eliminating fire and explosion risks. Intelligent frequency‑conversion control system dynamically adjusts operating load according to real‑time vapor flow and concentration, adapting to intermittent oil‑gas emission characteristics of filling stations. It avoids no‑load running and optimizes overall energy consumption.
Customized design is available according to practical parameters including actual vapor volume, emission characteristics, pipe network layout and site space of each gas station with sufficient working margin reserved. As a professional manufacturer, Vohon Petrochemical provides one‑stop services: site survey, process scheme design, equipment fabrication, on‑site installation & commissioning, operator training and after‑sales maintenance. Supported by standardized manufacturing and on‑site construction management, the VRU unit realizes compliant oil‑gas emission control and resource recovery for fuel stations.