ACARP ACARP ACARP ACARP
Mine Site Greenhouse Gas Mitigation

Selective Absorption of Methane by Ionic Liquids

Mine Site Greenhouse Gas Mitigation » Mine Site Greenhouse Gas Mitigation

Published: January 19Project Number: C27008

Get ReportAuthor: Behdad Moghtaderi and Andrew Maddocks | University of Newcastle

The connection of a ventilation air methane (VAM) abatement plant directly to a ventilation shaft raises significant safety issues for underground coal mines. Eliminating the risk of a fire or explosion caused by an abatement plant is considered a step-change in abatement technology. To eliminate this risk, the plant must operate below the autoignition temperature of methane. A concept developed by The University of Newcastle using ionic liquids can selectively absorb methane from ventilation air below 100°C. The process operates approximately 500°C below the autoignition temperature of methane, completely eliminating the risk of a mine fire caused by an abatement system. The ionic liquid looping process would produce a concentrated methane stream that could be utilised for power or heat. Hence VAM would be converted to carbon dioxide, reducing greenhouse gas emissions from the mining activities. The captured methane would be sufficient to provide the energy required for the process and therefore there would be no increase in the consumption of electricity for the process.

The principal vision of this project was to carry out fundamental investigations into the chemistry of ionic liquids and low-concentration methane mixtures and develop a proof-of-concept process for the absorption and desorption of methane using ionic liquids. To fulfil the above vision, the following objectives were defined:

  • Determine the effect of temperature on methane solubility and selectivity;
  • Determine the effect of pressure on methane solubility and selectivity;
  • Determine the optimal ionic liquid properties for the absorption of methane from low-concentration methane-air mixtures;
  • Determine the effect of temperature and pressure on the desorption rate of methane from ionic liquids;
  • Evaluate the performance of ionic liquids and undertake a preliminary feasibility assessment;
  • Report the key findings and provide recommendations for advancing the next phases of the program of study.

The key findings for the project were:

  • Methane absorption decreased with increasing ionic liquid molecular mass;
  • Gas absorption decreases with increasing temperature;
  • Gas absorption occurs at low pressures and increases with increasing pressure;
  • The absorption process is reversible when desorption occurs at moderate temperatures;
  • Methane is selectively absorbed from air at low concentrations, at selectivities greater than predicted ideal selectivities;
  • Overall assessment: from a technical standpoint the absorption of VAM using ionic liquids is quite feasible.

Translating the findings of this project to a practical unit for VAM abatement requires further examination of the process at laboratory- and pilot-scales under a continuous mode of operation. Such examinations are a key step in the transition from the fundamental chemistry investigations already completed in this project to the demonstration of the process in an appropriate absorption technology.

This project identified that the absorption process is not solely governed by the ionic liquid chemical properties and the ionic liquid physical properties and process conditions influence the quantity of methane absorbed. Given the scale dependency of process conditions, the investigations necessary to elucidate the mass transfer mechanisms and the key process variables must be conducted at laboratory- and pilot-scale. Packed beds were identified as the most suitable technology for gas absorption in ionic liquids. Specifically, rotating packed beds have shown to increase mass transfer rates by an order of magnitude compared with conventional packed beds. Given the high gas flow rates of ventilation air from underground coal mines, a high mass transfer rate is likely to be necessary for the absorption of VAM.

Underground

Health and safety, productivity and environment initiatives.

Recently Completed Projects

C27039True Triaxial Strength Of Coal Measure Rocks And Its Impact On Roadway Stability And Coal Burst Assessment

Rocks in the ground are subject to a range of stresses. The stresses...

C3063Underground Vehicle Design Standards And Statutory Implications

The Australian underground diesel vehicle fleet has evolved since di...

C3064Conveyor Belting And Lagging Shear Characteristics - Drive Drum Slip

The primary aim of this project was to investigate the relationsh...

Underground

Open Cut

Safety, productivity and the right to operate are priorities for open cut mine research.

Recently Completed Projects

C26029Geological Controls On Fluorine And Phosphorus In Bowen Basin Coals

Increasing global restrictions on fluorine in product coal prompted ...

C28033Raw Ash To Yield Relationships

Correct outcomes in yield predictions for product ash from coal bore...

C27038Establishing Self-Sustaining And Recognisable Ecological Mine Rehabilitation

In recent years an increasing interest has been placed on mining ope...

Open Cut

Coal Preparation

Maximising throughput and yield while minimising costs and emissions.

Recently Completed Projects

C27064Dry Beneficiation Using FGX And X-Ray Sorters

Conventional dry processing methods engage a single beneficiation de...

C26010Multi-Sloped Screening Efficiency With Changing Strokes, Frequencies, Feed Solids And Feed Rates-Pilot Plant Study

Optimising multi-sloped screens is often described as an art and the...

C28059Impact Of Water Quality In Coal Handling And Preparations Plants

The objective of this project was to deliver a concise reference do...

Coal Preparation

Technical Market Support

Market acceptance and emphasising the advantages of Australian coals.

Technical Market Support

Mine Site Greenhouse Gas Mitigation

Mitigating greenhouse gas emissions from the production of coal.

Recently Completed Projects

C23052Novel Stone Dust Looping Process For Ventilation Air Methane Abatement

This multi‐phase project is concerned with the mitigation of m...

C27054Optimisation Of A Thermal Flow Reversal Reactor For Ventilation Air Methane Mitigation

Ventilation air methane (VAM) generally accounts for 50-85% of the t...

C28076Selective Absorption Of Methane By Ionic Liquids (SAMIL) - Phase 2 Demonstration In A Packed Bed Reactor

An alternative approach to high temperature oxidation of ventilation...

Mine Site Greenhouse Gas Mitigation

Low Emission Coal Use

Step-change technologies aimed at reducing greenhouse gas emissions.

Recently Completed Projects

C17060BGasification Of Australian Coals

Four Australian coals were trialled in the Siemens 5 MWth pilot scale ga...

C17060AOxyfuel Technology For Carbon Capture And Storage Critical Clean Coal Technology - Interim Support

The status of oxy-fuel technology for first-generation plant is indicate...

C18007Review Of Underground Coal Gasification

This report consists of a broad review of underground coal gasification,...

Low Emission Coal Use

Mining And The Community

The relationship between mines and the local community.

Recently Completed Projects

C16027Assessing Housing And Labour Market Impacts Of Mining Developments In Bowen Basin Communities

The focus of this ACARP-funded project has been to identify a number...

C22029Understanding And Managing Cumulative Impacts Of Coal Mining And Other Land Uses In Regions With Diversified Economies

The coal industry operates in the context of competing land-uses that sh...

C23016Approval And Planning Assessment Of Black Coal Mines In NSW And Qld: A Review Of Economic Assessment Techniques

This reports on issues surrounding economic assessment and analysis ...

Mining And The Community

NERDDC

National Energy Research,Development & Demonstration Council (NERDDC) reports - pre 1992.

Recently Completed Projects

1609-C1609Self Heating of Spoil Piles from Open Cut Coal Mines

Self Heating of Spoil Piles from Open Cut Coal Mines

1301-C1301Stress Control Methods for Optimised Development...

Stress Control Methods for Optimised Development and Extraction Operations

0033-C1356Commissioned Report: Australian Thermal Coals...

Commissioned Report: Australian Thermal Coals - An Industry Handbook

NERDDC