Sepuran Green – Driving Change with Efficient Biogas Upgrading

Practical Experience with Membrane Technology

At our manufacturing plant, separation technology remains at the core of how we handle natural and renewable gas streams. The Sepuran Green Evonik Eco Separation Membrane stands out in everyday operation for its unique ability to distinguish methane from carbon dioxide efficiently, supporting a cleaner energy cycle for industries transitioning to biogas. We have seen growing global interest in biogas upgrading, which focuses on turning raw biogas into pipeline-quality biomethane. Without a robust membrane, loss of methane or inefficient separation can cripple project viability, especially for installations in rural or agricultural settings, where feedstock variability is frequent.

Model and Technical Backbone

We make the Sepuran Green module using a hollow-fiber design that offers a high surface area for gas contact within a compact footprint. This matters when working with confined space, tight plant-room layouts, or in mobile upgrading units. The membrane operates at moderate pressures—our teams typically run modules at feed pressures of up to 16 bar. Operating within this pressure range brings down compressor requirements, delivering savings on both equipment and energy consumption. Our 4040 and 6080 series, referencing the shell diameter and length in millimeters, are the modules most customers deploy across Europe and North America.

To us as manufacturers, repeatability and reliability under variable temperature, humidity, and mixed-gas conditions mark the real test. Every Sepuran Green module we ship gets pressure-tested and checked for fiber integrity. A module’s ability to manage sulfur, heavier hydrocarbons, or trace siloxanes means less downtime for backflushing, acid-cleaning, or renewal. The polyimide-based chemistry of our fibers makes this possible, retaining selectivity and mechanical strength throughout continuous cycles.

Energy Savings and Field Results

For companies integrating our modules, we have seen typical methane recovery exceeding 97%—meaning more biogas gets converted to pipeline-grade biomethane rather than vented as fugitive emissions. Saving that last margin of methane stands out on the invoice month-after-month, especially at times of high gas prices. In our own test loops, and those of large utilities in Sweden and Germany, we track CO2 content drop-off rates below 0.5% in the product stream. That satisfies domestic grid standards and, equally important, meets the requirements of fleet vehicle operators switching to renewable natural gas.

We shape the multi-stage membrane process for each customer’s feedstock. Wastewater facilities, farm digesters, and landfill gas each bring their own mix of contaminants and production peaks. Sepuran Green’s modular structure lets operators tune gas composition by changing the number of modules in parallel or series. We designed housings to allow swapping a module within minutes, using simple clamp connections. This keeps service stops short and production uptime high. Less time troubleshooting means a plant’s productivity stays up, with most plant managers reporting maintenance intervals extending past 18 months in mild atmospheres.

Why Membranes Over Other Biogas Upgrading Methods

Our technical teams have hands-on experience with water wash, chemical wash, and pressure swing absorption systems as legacy solutions. These methods need extra chemicals, water treatment, and significant maintenance, adding operating cost and environmental burden. Membranes use no water, generate no secondary liquid effluents, and operate in a dry environment. The Sepuran Green approach trims auxiliary needs, avoiding the complications of soda lye, amine, or glycol losses. Our modules deliver consistent performance year-round, even during cold snaps or surges in biogas throughput—proven across climates from Norway to South Korea.

In older upgrading installations, system scaling, foaming, or amine degradation leads to unpredictable product quality. After retrofitting with Sepuran Green, plant operators have reported smoother gas flows and fewer shutdowns, with data sheets to support drop-in replacement in legacy setups. For mobile systems or quick-deployment applications, no need for on-site water tanks or waste-handling. This is why networks of mobile upgraders, especially in regions like Bavaria and Denmark where feed-in points are dispersed, often opt for hollow-fiber modules.

Real-World Feedback and Industry Trends

Customers in the livestock, municipal waste, and food processing sectors drive our product development. We sit with engineers at digester plants seeing daily fluctuations in organics or water content. Feedback led us to boost module resilience against ammonia and sulfur—key worries in digestate and landfill gases. Today’s Sepuran Green models deliver a higher flux and contamination tolerance compared to earlier polymers. Upgrading facilities in Ontario processing food waste commented on direct savings from fewer downtime events and reduced scrubber cleaning cycles.

Expanding biogas production aligns with global decarbonization goals. In Europe, government incentives and carbon pricing demand robust and auditable methane recovery. We’ve responded by developing modules capable of continuous monitoring—optical sensors in select models help track performance over time. Remote diagnostics allow us or plant integrators to identify fouling or fiber damage early, minimizing lost production or costly emergency repairs. Some of our modules now embed RFID tags and electronic serials for instant traceability and compliance audits.

What Sets Sepuran Green Apart

Plastics science governs the backbone of every fiber bundle inside our membranes. Our R&D team developed a dedicated polyimide—a tough, chemical-resistant material—that endures pressure and gas shocks that would degrade standard cellulose or polysulfone modules. With this backbone, our hollow fibers deliver a sharp cut between methane and CO2. This selectivity stands above most commercial competitors, especially under varying humidity or trace contaminant load.

Early hollow-fiber technology had challenges with pressure creep, shrinkage, or plasticizer migration leading to reduced lifespans. Our manufacturing process tightly controls temperature and dope ratios, setting fiber wall thickness according to applications. Modules running in North American dairy digesters, for instance, see long life in spite of daily production swings and feedstock changes, providing field evidence for robust chemistry and process control.

Environmental Impact and Operational Sustainability

Waste management and emissions reduction set the agenda for today’s gas upgrading facilities. We built the Sepuran Green production process to minimize offcuts and waste, using automated winding and precision extrusion. Plant runs usually generate minimal production rejects—almost all fibers end up fitted and tested into certified modules rather than discarded. This keeps resource intensity in check for every cubic meter of separation area shipped.

During plant commissioning, we see reduced emissions not only from methane slip but also from the absence of bleed air or vented process water. For community-scale installations in France and Italy, site reports point to cleaner operation and reduced compliance headaches—no chemical storage, no contaminated waste tanks, and fewer staff needed on-site for chemical handling.

Our field data shows a direct reduction in greenhouse gas equivalent emissions. By shifting separation loads from fossil-based natural gas to renewable methane, operators report an improved carbon footprint and a faster payback from carbon credits or renewable gas incentives.

Ease of Integration into Existing Infrastructure

Utility companies and energy contractors consistently ask for modularity and rapid commissioning. We ship Sepuran Green modules ready to integrate with a range of compressors, dryers, and monitoring systems. Site teams often retrofit into existing skids without extensive layout changes, connecting using industry-standard adapters. The dry-process setup eliminates the calls for additional permits or wastewater discharge connections, speeding up project timelines.

With nearly a decade of support, our product managers work with system integrators to select the right number, orientation, and staging of modules. In one case, a municipal digester required staged flow to handle varying landfill gas production. After simulation, we adjusted module counts seasonally, helping the operator hit biomethane yield and quality targets despite fluctuations. Modular swapping and scaling up accommodate growth without requiring complete overhaul or investment in new plant buildings.

Long-Term Cost and Risk Management

Operational costs relate not just to energy and input chemical savings but to reduced downtime and maintenance. In regions with a highly variable biogas composition, modules facing spikes in ammonia or siloxanes maintain performance with minimal cleaning cycles. Plant operators tell us downtime drops by a measurable percent compared to chemical wash columns. Recurring costs for replacement modules remain predictable and spread evenly across service intervals.

Insurance underwriters in the renewable gas field care about operational risk from leaks, fire, or process upsets. Dry membranes eliminate many of the accident scenarios that come from liquid-based separations—no corrosion, less risk to electrical infrastructure, and lower toxic chemical exposure for staff.

For larger utilities, regulatory audits highlight traceability and process documentation. Newly deployed Sepuran Green modules ship with test reports and digital IDs for process validation and environmental tracking.

Shaping the Future of Gas Upgrading

Over the last fifteen years, customer demand and government regulations drove the evolution of our membranes. Plant managers want reliability so that their operations yield predictable biomethane feeds suitable for regional gas grid injection, vehicle filling stations, or power production. New feedstocks—ranging from industrial waste to seaweed digestion—bring changing challenges, driving continuous innovation in membrane chemistry and module geometry.

Collaborating with universities and research labs, our development teams focus on reducing pressure drop, boosting methane recovery, and extending module lifetimes under adverse conditions. Internal test beds cycle modules through high H2S, humid, and methane-rich atmospheres to simulate worst-case scenarios. Our data influences not only future product lines but also troubleshooting handbooks for operators.

Regulatory shifts in North America and Asia require clear demonstration of greenhouse gas reductions. Through process monitoring and lifecycle analysis, Sepuran Green-equipped plants deliver quantifiable methane savings and lower overall emissions—critical for meeting corporate and public climate targets.

Field Learning: From Start-up to Expansion

Start-up and expansion phases in gas upgrading present unique hurdles. Early operation after installation sees fluctuating gas flows, uncertain contaminant loads, and the need to adapt membrane staging. Our engineers spend startup weeks on-site, monitoring every valve setting and module output to fine-tune for real conditions. Later, as biogas production stabilizes and grows, expansions happen through “plug and play” addition of matching modules. No complex engineering, plus minimal process downtime for scaling up.

Learning from dozens of such deployments, we train operators not just in swapping modules, but in reading differential pressures, getting ahead of fouling trends, and logging performance baselines. Hands-on knowledge from farms in Minnesota to wastewater plants in Spain shapes ongoing refinements—each cycle yields faster swap times, longer module intervals, and higher net methane yields.

Our support does not end after delivery. Remote diagnostics, technical manuals, and expert staff support keep plants running smoothly, often preventing issues before they grow —a difference that translates directly to plant profitability.

Industry Partnerships and Shifting Customer Needs

Growth in distributed biogas production creates fresh requirements. Smallholders in rural Germany want low-maintenance systems. Mega-interceptor projects in the United States need modules able to handle wide swings in gas volume. Sepuran Green’s versatility allows us to serve both ends of the spectrum. Field partners and installers frequently return with new applications—from marine digesters Upgrading algal biomass to on-farm anaerobic systems with diverse substrates.

To meet these needs, we built flexibility into every fiber. Plant contractors specify gas analysis target values; we ship modules tailored for each case. In challenging climates or where resource constraints persist, the membrane’s resistance to freezing, surface wetting, and fluctuating pressure keeps it operational long after other systems falter.

Installers note the competitive costs over time and the reliability under practical field pressures—not just in the lab but in day-to-day plant operation. We credit ongoing feedback from our global customer base for pushing us to innovate and improve with every production run.

Beyond Biogas: Versatility for Industrial Separation

Membrane technology now improves more than just biomethane recovery. Emerging applications include hydrogen separation, landfill gas purification, and even off-gas treatment from chemical reactors. Using the same principles of selective permeation, Sepuran Green separates methane from nitrogen, oxygen, and trace siloxanes—a benefit in specialty chemical and landfill sectors.

In field trials, we have combined our modules with adsorption beds for deep hydrocarbon removal or dehydration stages, supplying purified gas to downstream power gen or fuel cell systems. The key lies in the module’s ability to retain its fractionation edge across a broad mix of gases, supporting new product pipelines for industrial upcycling and greenhouse gas abatement.

What Experience Taught Us

After decades in polymer and membrane manufacturing, one lesson sticks out: performance in the field trumps specifications on paper. Each Sepuran Green module measures up, both in test tanks and under the relentless loads of daily plant life. Reliable biomethane, less operator labor, reduced environmental burden, and minimal auxiliary needs—these define a well-built membrane system.

We built Sepuran Green for forward-thinking operators who demand robust, scalable performance. Our ongoing investment in fiber chemistry, module housing design, and installation support means today’s and tomorrow’s gas upgrading projects gain a proven path to high-purity biomethane and a measurable climate benefit.

Direct feedback from the field, rigorous quality assurance, and a track record of operational savings give us confidence in the separation membrane technology shaping renewable energy. We see the future of clean gas streams and environmental stewardship riding on manufacturing quality, real-world reliability, and a willingness to match technology with the workforce keeping the lights on and the engines running.