Case Study: 3-Stage Vapor Recovery Unit at PetroChina Manchunjie Station
Location: PetroChina Manchunjie Filling Station
Equipment: Vohon WHSH-M 3-Stage Vapor Recovery Unit
In operation since: 2024
With increasingly stringent environmental requirements, vapor vented from underground storage tanks at filling stations must be recovered and treated before discharge. After completing its Stage-2 vapor recovery retrofit, the PetroChina Manchunjie station selected the Vohon WHSH-M 3-stage vapor recovery unit for deep treatment of vapor from tank breather valves.
How the Unit Works
The WHSH-M uses membrane separation technology. When fuel is being delivered or tank pressure exceeds the preset value, the unit starts automatically: vapor is pressurized, cooled and separated into liquid and gas; the condensed fuel returns to the tank, while the remaining gas enters the membrane module, where hydrocarbon molecules pass through the membrane under vacuum pump suction and flow back to the tank. Purified air is vented directly. When tank pressure falls to the stop value, the unit returns to standby — fully unattended operation.
Measured Field Performance
Since commissioning, the unit has run stably. Live readings from the HMI show the outlet concentration remaining at 1.5–2 g/m³, roughly 1/13 of the national emission limit (25 g/m³). Historical logs (September 3, 2024) confirm consistent performance at around 1.5 g/m³.
Results
① Guaranteed compliance — outlet concentration far below the national emission limit;
② Low energy consumption — only 2.5–3 kW, with automatic start/stop;
③ Fuel savings — recovered liquid fuel flows directly back to the tank, reducing product loss;
④ Low maintenance — PLC automatic control, unattended operation, remote monitoring and fault self-diagnostics; only monthly routine checks required.
About Vohon
Luoyang Vohon Petrochemical Equipment Co., Ltd. specializes in the design and manufacture of vapor recovery systems. The WHSH series 3-stage vapor recovery units feature self-developed membrane separation technology, processing capacities of 4–20 m³/h, and explosion-proof construction — suitable for gas stations, fuel terminals, ports and chemical storage facilities. Contact us: +86 379 6529 0028 | www.vohon.cn