to Renewable Natural Gas (RNG)
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.
Biogas Upgrading with Membrane 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. As a global market leader, DMT offers the Carborex®MS, high-selective membrane separation technology, for biogas upgrading. Advantages of the system include low energy consumption, a small footprint and high methane recovery.
Your biogas upgrading system in 5 easy steps!
Pre-Treatment and Compression
For biogas upgrading systems, also known as renewable natural gas (RNG) facilities, biogas must pre-treated and compressed before entering the membranes. Contaminants in the biogas stream, such as hydrogen sulfide (H₂S), ammonia (NH₃), mercaptans, VOC’s and siloxanes, are removed during pre-treatment. After the biogas is pre-treated, biogas is compressed to 10-20 bar. This pressure optimizes the separation of methane and carbon dioxide by increasing the permeability of the membrane.
Multi-stage Membrane Separation
As compressed gas 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: Gas that is retained and collected at the end of the membrane fiber
- Selectivity: Ability of a membrane to predictably meet required separation performance expectations
Depending on the biogas inlet flow and the desired methane recovery, the amount of membranes and stages inside the Carborex®MS will vary. The two-stage methane recovery unit can reach up to 97% while the three-stage methane recovery unit can reach up to 99.5%.
Renewable Natural Gas (RNG) Applications
Renewable natural gas (RNG), also known as biomethane, is renewable energy. 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.
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). For a successful project, selecting a biogas upgrading system that can reliably meet the CH4, O2, CO2, nitrogen and H2S specifications is critical.
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.
Is renewable natural gas (RNG) clean?
Renewable natural gas (RNG), also known as biomethane, creates a local resource of renewable energy. The benefits of RNG include:
- Environmental Benefits. Reduces greenhouse gas emissions, pathogen levels, nutrient runoff, and odor. RNG also increases crop yield.
- Economic Benefits. Creates green jobs both temporary and permanent. Most importantly, renewable natural gas converts gas normally flared into the atmosphere or waste into a revenue-stream. Economic benefits include improving rural infrastructure as well as diversifying rural income streams. RNG can also operate in conjunction with composting operations.
- Energy Security. Increases our domestic production of non-fossil fuel energy. There are multiple end-use applications for RNG such as heat only, electric only, CHP, pipeline injection, or transportation fuel.
- Waste Treatment Management. Improves the natural waste treatment process. RNG also creates a smaller physical footprint. It reduces the volume of transport and land application.