Key Takeaways
- Greenlane Renewables’ proprietary Linear Nitrogen Rejection Unit (NRU) achieves up to 99.5 % methane recovery while removing nitrogen from landfill gas to pipeline‑quality renewable natural gas (RNG) specifications.
- The Linear NRU is based on equilibrium pressure‑swing adsorption (PSA) but uses fewer, smaller adsorption beds, eliminates internal gas recycling, and offers a modular, low‑cost architecture that scales with nitrogen concentration.
- Testing showed:
- 4 % N₂ → 99.5 % recovery (single unit)
- 8 % N₂ → 98.5 % total recovery (two units in series)
- 15 % N₂ → 97.0 % total recovery (three units in series)
- When paired with automated well‑field control technology, the Cascade LF system can stabilize gas quality, limit nitrogen to < 8 % (or < 4 %) and boost methane flow, further improving economics.
- Conventional landfill‑gas upgrading systems typically recover < 90 % methane and cost about double comparable anaerobic‑digester biogas upgrades; Cascade LF delivers lower cost, lower technology risk, and higher performance.
- Greenlane positions the technology as a catalyst for scalable, accessible RNG projects, aligning with global energy‑security and decarbonization goals.
Overview of the Announcement
On May 19, 2026, Greenlane Renewables Inc. (TSX: GRN; FSE: 52G) disclosed that recent testing of its proprietary Linear Nitrogen Rejection Unit (NRU) achieved breakthrough methane recovery performance of up to 99.5 %. The Linear NRU forms the core of Greenlane’s next‑generation Cascade LF landfill‑gas upgrading system, which is engineered to strip nitrogen from landfill gas while maximizing methane capture in a configurable, low‑cost architecture.
Technology Foundations
The Linear NRU operates on equilibrium pressure‑swing adsorption (PSA) principles. Unlike conventional PSA systems, it employs a stepwise methane‑enrichment process that uses fewer and smaller adsorption beds and eliminates the internal gas‑recycling step, which traditionally wastes both operating cost and methane. For landfill streams with higher nitrogen content, the design is modular: additional adsorption beds and compression stages can be added in a linear, staged configuration without altering the fundamental process flow.
Prototype Development and Test Methodology
To validate the design, Greenlane engineers built a scaled‑down prototype of the Linear NRU, installed it in a controlled test environment, and heavily instrumented it to capture all process variables. A series of tests used mixed gases containing methane, nitrogen, and oxygen in ratios that mirror the varied quality of real‑world landfill gas. The test program aimed to verify methane recovery across the full spectrum of nitrogen levels typically encountered in landfill streams.
Performance Results for Low‑Nitrogen Gas
When processing landfill gas equivalent to 4 % nitrogen, a single Linear NRU achieved 99.5 % methane recovery. This figure reflects the amount of methane remaining in the product gas relative to the inlet stream, after meeting a typical pipeline‑injection RNG methane purity specification of 96 %. The result does not account for any methane loss that may occur during an upstream carbon‑dioxide removal step.
Performance Results for Moderate‑Nitrogen Gas
For landfill gas containing ≈ 8 % nitrogen, the system employs two Linear NRUs in series. Testing showed 99.0 % recovery in the first unit and 99.5 % in the second, yielding a combined nitrogen‑removal methane recovery of 98.5 %. The modular approach allows the system to maintain high efficiency while handling the increased nitrogen load.
Performance Results for High‑Nitrogen Gas
With ≈ 15 % nitrogen in the feed, three Linear NRUs are staged sequentially. The first unit delivered 98.5 % recovery, the second 99.0 %, and the third 99.5 %, for an overall methane recovery of 97.0 %. Even at this challenging nitrogen concentration, the Linear NRU outperforms many conventional technologies, which often fall below 90 % recovery.
Synergy with Automated Well‑Field Control
Optimal performance is realized when the Cascade LF system is paired with automated well‑field monitoring and control technology. Such automation stabilizes gas quality across the wellfield, enables operators to increase vacuum safely, and can limit nitrogen concentrations to under 8 % (or even 4 %) while simultaneously raising methane flow rates. This synergy further enhances the economic attractiveness of the upgrading system.
Economic and Competitive Advantages
Methane recovery is the primary performance metric for any biogas upgrading plant because each 1 % improvement translates directly into a 1 % increase in project revenue, impacting the bottom line. The industry benchmark for anaerobic‑digester biogas upgrading is 99.5 % methane recovery, a target that does not contend with nitrogen removal. Greenlane’s Linear NRU demonstrates that this benchmark can be met—or exceeded—when upgrading nitrogen‑rich landfill gas.
In contrast, conventional landfill‑gas upgrading systems that achieve pipeline‑quality RNG often recover less than 90 % methane and can cost approximately double comparable systems for anaerobic‑digester biogas of the same size. Cascade LF’s simplified, low‑cost architecture reduces technology risk, offers scalability through modular NRU units, and delivers superior methane recovery at a lower capital and operational expense.
Leadership Statements
Brad Douville, CEO of Greenlane, emphasized that customers repeatedly request lower‑cost, higher‑performing solutions that enable them to build more RNG projects and scale their portfolios without adding new technology risk. He noted that the Cascade LF system, featuring the Linear NRU, fulfills these demands by delivering enhanced methane recovery, reduced costs, and proven reliability.
Dale Goudie, Chief Technology Officer, presented the testing results in a video available on the company’s website, underscoring that the experimental outcomes aligned closely with model predictions grounded in adsorption fundamentals, reinforcing confidence in the technology’s scalability.
Company Background and Vision
Greenlane Renewables has over 35 years of experience in biogas desulfurization and upgrading, with more than 500 systems deployed across 32 countries. The company transforms biogas from sources such as landfills, sugar mills, dairy farms, wastewater, and food waste into grid‑ready renewable natural gas (RNG), thereby supporting decarbonization of the natural‑gas grid and commercial transportation sectors. Greenlane’s mission is to make RNG projects globally accessible and scalable, enabling owners to increase revenue‑generating output while minimizing upfront investment.
Forward‑Looking Context
The press release includes customary forward‑looking statements concerning expected performance, cost advantages, reliability, scalability, and market adoption of the Cascade LF system and Linear NRU technology. These statements are based on current assumptions regarding test accuracy, industry trends, regulatory developments, successful commercialization, and market demand. Readers are cautioned that actual results may differ due to risks and uncertainties inherent to emerging technologies and market conditions.
Conclusion
Greenlane’s Linear NRU represents a significant advancement in landfill‑gas upgrading, delivering near‑total methane recovery while simplifying the process, cutting costs, and reducing technological risk. By integrating modular NRU units with automated well‑field control, the Cascade LF system offers a robust, economically viable pathway to expand RNG production from landfill gas—a crucial step toward a more secure, low‑carbon energy future.