Featured Project: Sub-Zero Butane Vapour Sphere Degassing – Dual CSA-Compliant EMECS-70 (Canada)
A major Canadian refinery transitioning to renewable diesel production needed to degas and vapour free a large butane storage sphere for internal cleaning and inspection during winter conditions, utilizing advanced vapour degassing techniques.
The challenge was extreme:
- High-LEL butane vapours that needed tank degassing and vapour mitigation
- Ambient temperatures below −30 °C
- Strict Canadian Council of Ministers of the Environment (CCME) and provincial air quality standards
- Must maintain <1% LEL and prevent oxygen ingress (pyrophoric risk)
- Full compliance with Canadian Regulations for Reduction in the Release of Volatile Organic Compounds (Storage and Loading of Volatile Petroleum Liquids) Regulations, and;
- Measuring VOC Vapour Concentration in Tanks Equipped with an Internal Floating Roof
Envent’s CSA-Certified Turnkey Solution
| Equipment & Service | Role & Link |
|---|---|
| Dual CSA-Compliant EMECS-70 | 70 MMBTU/hr each → >99.9% DRE of butane vapours |
| Heated Nitrogen Generation System | Pre-heated N₂ injection to prevent condensation & maintain <12% O₂ |
| Integration with existing flare header | Seamless tie-in, zero atmospheric release |
| 24/7 Envent Canadian-certified operators | Continuous LEL, O₂, temperature monitoring |
- Tank brought from 100% LEL to <1% LEL in under 48 hours, showcasing the effectiveness of vapour degassing.
- Zero condensation or ice formation in lines
- Zero odours, zero visible plume, zero complaints
Proven Results – Winter-Ready, Regulator-Approved
| Benefit | Delivered Outcome |
|---|---|
| Speed | <48 hrs to gas-free (vs. 5–7 days conventional) |
| Safety | Heated N₂ + dual redundancy = zero pyrophoric or freeze-up risk |
| Compliance | 100% CSA B149.3, CCME, and provincial air permit compliant |
| Environmental | >99.9% destruction, no flaring, no venting |
| Operational | No delay to renewable diesel transition schedule |
This project set the new Canadian benchmark for cold-weather butane/LPG sphere degassing and remains the preferred method for Western Canada refineries, highlighting the importance of vapour degassing in harsh winter conditions.
Planning a butane, propane, or LPG tank degas in Canada? Vapour degassing solutions can enhance performance. Get your Free CSA-Compliant Degassing Plan & Quote today. Call Envent Canada at 888-997-9465 or email [email protected] — we’re fully CSA-certified and winter-ready.
