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The challenge

Why mine methane is so hard to tackle

Methane from underground coal seams is a serious safety hazard and a significant source of greenhouse gas emissions. Mines use ventilation systems to dilute methane and move it out of underground workings, creating an exhaust stream known as ventilation air methane (VAM).

Although methane concentrations in VAM are low, the air volumes are huge, making the gas difficult to treat.

VAM is a major source of fugitive emissions from underground coal mining. Methane is around 28 times more potent than carbon dioxide in trapping heat in the atmosphere.

The challenge is increasing as mine ventilation systems improve. Methane concentrations in Australian mine ventilation air now typically range from 0.2 to 0.4 per cent, with even lower concentrations occurring for substantial periods. That makes conventional high-temperature systems harder to operate efficiently.

Australia’s Safeguard Mechanism is also increasing pressure on large industrial facilities, including mines, to reduce emissions over time.

Our response

CataVAM™ destroys methane from mine ventilation air

This diagram shows a cross-sectional view of a coal mining operation, illustrating both surface infrastructure and underground workings, and how ventilation air methane (VAM) is captured and treated using CaTaVAM technology.

At the top of the image is the land surface, drawn as a flat to gently sloping landscape. Surface infrastructure includes a mine site with buildings, access roads, and ventilation equipment. Several large ventilation fans sit at the surface, connected to vertical shafts that extend down into the underground mine. These fans are used to move large volumes of air through the mine to keep it safe for workers. Arrows indicate airflow direction, showing fresh air being drawn into the mine and methane-containing air being pushed out through return air shafts.

Below the surface, the diagram reveals the underground mine network. This consists of horizontal tunnels (roadways) extending through coal seams. The coal seam is shown as a dark horizontal layer within lighter-coloured surrounding rock. Mining equipment, such as longwall machinery, operates along the coal seam, extracting coal. Workers and vehicles may be depicted within the tunnels to show scale.

Airflow is clearly marked throughout the underground workings. Fresh air enters through intake shafts and tunnels, flowing across active mining areas. As it passes through, it mixes with methane released from the coal seam. This creates ventilation air methane (VAM), which is low in concentration but present in very large volumes. The air, now containing diluted methane, is directed toward return airways and exits the mine through return shafts.

At the surface, the return air is captured and channelled toward a CataVAM system. This system is represented as a treatment unit connected to the ventilation exhaust. Arrows show the methane-containing air moving from the mine into the CataVAM reactor.

Inside the CataVAM unit, the diagram may depict a reactor chamber or catalytic oxidation system. This is where methane in the ventilation air is converted into carbon dioxide and water vapour. Labels or icons may indicate heat generation, oxidation, or catalytic processes, emphasising that the methane is safely destroyed rather than released into the atmosphere.

In some versions of the diagram, heat generated by the oxidation process is shown being recovered and reused. This may be illustrated with arrows leading from the CataVAM unit to energy recovery or reuse applications, such as power generation or heating systems.

The overall flow of the system is presented as a clear sequence:

  1. Methane is released from the coal seam during mining.
  2. Ventilation air dilutes and carries the methane through underground tunnels.
  3. Air is extracted via return shafts using surface fans.
  4. Methane-containing air is directed into the CataVAM system.
  5. Methane is oxidised, reducing greenhouse gas emissions.

Colour and arrows are used throughout the diagram to distinguish between fresh air (often shown in blue or green tones) and methane-containing air (often shown in warmer colours such as orange or red). Labels identify key components, including intake shafts, return shafts, coal seam, mining equipment, ventilation fans, and the CataVAM treatment unit.

Overall, the diagram communicates how underground coal mining generates ventilation air methane and how CataVAM technology captures and treats this dilute methane stream at the surface to reduce emissions

Mine ventilation diagram showing how fresh air moves through underground workings and exits as ventilation air methane (VAM). At the surface, the methane-diluted exhaust stream passes through a CataVAM unit designed to destroy low-concentration methane (AI-generated schematic).

CSIRO developed CataVAM™, a catalytic methane abatement technology tailored to the low methane concentrations typically found in Australian mine ventilation air. CataVAM™ has arisen from nearly two decades of CSIRO research into methane abatement, building upon including earlier technologies such as VAMCAT, VAMCAP and VAMMIT. 

Using high-performance catalysts and an innovative regenerative bed, CataVAM™ destroys methane in the 0.2 to 0.4 per cent range without the need for supplemental fuel. It has a modular, transportable design which makes it practical for mine sites to use, redeploy and scale up or down as required.

At the core of the system is a proprietary honeycomb catalytic regenerative bed designed to improve heat transfer, airflow and catalytic efficiency. It supports stable autothermal operation at lower temperatures and with low flow resistance, helping improve energy efficiency and durability.

The results

Tested technology for real mine conditions

In a world-first, CSIRO trialled a large-scale CataVAM™ pilot at GM3 Appin mine in southern New South Wales using real mine ventilation air. Completed in April 2026, the trials processed airflows of up to 1.38 cubic metres per second and destroyed more than 98 per cent of the methane, taking the technology to Technology Readiness Level 7 (TRL-7).

Next up is scaling the system to an intermediate unit of around 5 cubic metres per second, with a commercial module of about 20 cubic metres per second designed to operate in parallel at mine shafts.

CSIRO’s CataVAM demonstration unit installed at Appin coal mine, capturing and treating ventilation air methane to reduce greenhouse gas emissions.

This work has been supported by long-term collaboration between CSIRO, government and industry. Internal project material states that CSIRO’s fugitive methane emissions abatement research has been supported by the ACARP, ACALET, the Department of Industry (DOI), Coal Innovation NSW (CINSW), the Australian Government Department of Industry, Science and Resources (DISR), the Australian Government Department of Foreign Affairs and Trade (DFAT), bilateral government programs and the mining industry.

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Capturing fugutives with CataVAM™