Biogas Upgrading to Renewable Natural Gas (RNG)
Membrane Separation Technology
Upgrade to the Carborex® MS.
Maximize site performance with our Membrane Separation (MS) technology for CO₂ removal. Our standardized designs for various inlets offer no columns, chemicals or water to operate, allowing for low operational costs. Operation of the system is easy and can be monitored remotely 24/7.
- Highest Uptime.
- Up to 99.5% Methane Recovery.
- Low OPEX.
Membrane Separation Technology
Membrane technology is the most preferred equipment in the biogas industry due to key factors that affect a RNG plant’s ROI, such as energy efficiency, methane slip or plant uptime. DMT Clear Gas Solutions focuses exclusively on membrane technology for biogas upgrading, or CO₂ removal. With 60 DMT membrane systems worldwide, it’s clear why project developers continue to use our technology for RNG projects.
Biogas Upgrading Technology – Carborex®MS
For biogas upgrading, DMT offers the Carborex®MS, our high-selective membrane separation technology. Overall, the benefits of the Carborex®MS include high methane recovery, uptime reliability, low energy consumption, a small footprint, operational ease, fast start-up and low maintenance.
How does membrane separation work?
To summarize, DMT’s membrane separation technology, the Carborex® MS, uses polymeric membranes to extract carbon dioxide (CO2) from biogas. What remains is a methane (CH₄) rich byproduct. Raw biogas will undergo pre-treatment, compression, multi-stage membrane separation, and quality control before it becomes renewable natural gas suitable for pipeline injection or vehicle fuel.
Pre-Treatment and Compression
DMT’s biogas upgrading system pre-treats and compresses the biogas before entering the membranes. During pre-treatment, we remove contaminants in the biogas stream, such as hydrogen sulfide (H₂S), ammonia (NH₃), mercaptans, VOC’s and siloxanes. As a result of compression, this pressure optimizes the separation of methane and carbon dioxide by increasing the permeability of the membrane.
Multi-stage Membrane Separation
As compressed biogas travels down the length of the fiber, carbon dioxide will permeate through the porous membrane leaving methane as the retentate.
Terminology regarding membrane separation technology:
- Permeate: Gas that has traveled through the porous membrane
- Retentate: Retained and collected gas at the end of the membrane fiber
- Selectivity: Ability of a membrane to predictably meet required separation performance expectations
Furthermore, the amount of membranes and stages inside the Carborex®MS will vary depending on the biogas inlet flow and the desired methane recovery. The two-stage methane recovery unit reaches up to 97% while the three-stage methane recovery unit reaches up to 99.5%.
Renewable Natural Gas (RNG) Applications
The remaining byproduct is renewable natural gas (RNG), also known as biomethane. RNG can be blended with or otherwise serve as a direct substitute for the following natural gas applications without any operational changes:
- Drop-in vehicle fuel.
- Renewable electric power generation.
- Any daily in-home use.
Switching to RNG is easy, requiring no additional capital investment for Compressed Natural Gas (CNG) or Liquefied Natural Gas (LNG) ready fleets.
Additional Biogas Upgrading Features
Additionally, our configured system offers recoverable carbon dioxide (CO2) as a by-product which can be sold to the food and beverage industry for ingredient use. This feature creates an almost zero emissions system where all the feed gas is recovered as either pure methane or pure carbon dioxide.
What is biogas upgrading?
Biogas upgrading removes trace impurities in the biogas stream. The main goal is to separate carbon dioxide (CO₂) from methane (CH₄) to produce renewable natural gas (RNG). Consequently, selecting a biogas upgrading system that reliably meets the CH4, O2, CO2, nitrogen and H2S specifications is critical for a successful project.
Furthermore, the specification of RNG will vary based on application and the gas utility off-taker requirements. RNG is then injected into the natural gas grid and/or direct use for vehicle fuel.
Why work with DMT?
DMT has been in the biogas conditioning and upgrading industry since 1987. We offer 130 worldwide references and more than 30 years of biogas experience.
Your Local Total Solutions Provider
DMT is your local total solutions partner from financing options to 24/7 service support. Price, delivery time, and reliability, for instance, are a few factors that keep DMT thriving in a tough, competitive industry. But partners need more than just meeting specifications. When the going gets tough, clients want a knowledgeable partner that will be there every step of the way. In short, DMT is that partner.