What is post-combustion capture?

The effective capture of carbon dioxide (CO2) emitted from sources such as coal-fired power stations is an important strategy in the reduction of greenhouse gas emissions in NSW.

One of the most promising capture methods available is Post-Combustion Capture (PCC) which involves the separation and concentration of the CO2 from flue gas obtained after the combustion of coal.

This technology has desirable advantages. It is based on mature techniques currently used in oil refineries, petrochemical plants and other industries, and it can be retrofitted to existing power stations. This negates the expensive task of constructing or substantially modifying existing power station facilities and hence provides an avenue for near-term CO2 capture.

The Post-combustion capture process.
The Post-combustion capture process. Courtesy of CO2CRC.

Various techniques are being developed throughout the world to effectively capture CO2 in a cost-efficient manner. The leading technology is based on liquid absorbent capture technology which uses chemical liquids to specifically target and remove the CO2 from the power station flue gas stream. Other technologies, such as membrane sieves and physical adsorption, are also being investigated as alternative or supplementary options to chemical liquid absorption.

Seven projects have been supported by the Coal innovation NSW Fund to assist in readying the NSW fleet of coal-fuelled power stations to capture and abate their greenhouse gas emissions.

Project: Further development of an aqueous ammonia process for post-combustion capture of CO2 in the NSW power sector

The challenge:

To evaluate and assess solvent based post combustion capture technologies at a pilot scale with real flue gas conditions in NSW coal fired power stations

The action:

Coal Innovation NSW funded CSIRO to develop a post combustion capture pilot plant test facility for NSW coal fired power stations.

Grant amount:

$1.3 million (EOI Round 2009)

The project:

CSIRO Energy Technology received grant funding in 2010 to support a research and development program dedicated to the chemical capture of CO2 emitted in the flue gas from NSW coal-fired power stations. This project was designed to enable further development of PCC in preparation for a larger scale demonstration of the technology.

This successful project involved the refurbishment and modification of a post combustion pilot plant following its transportation from Munmorah Power Station to Vales Point Power Station. This pilot plant is now a critical piece of test infrastructure that can stage many different experimental campaigns on real flue gas under real power station operating conditions.

So far three projects have been completed with the support of the pilot plant including the:

  • CSIRO’s ‘Site Trials of Novel CO2 Capture Technology at Delta Electricity ’ Project - funded by Coal Innovation NSW
  • University of New South Wales’ ‘Evaluation of CO2 Capture with High Performance Hollow Fiber Membranes from Flue Gas: A Pilot Scale Study’ Project – funded by ANLEC R&D/CO2CRC
  • CSIRO’s ‘Hybridisation of concentrated solar thermal with carbon capture and storage’ Project – funded by Australian Renewable Energy Association (ARENA)

This project has been completed and the final report, Delta Electricity PCC pilot plant relocation from Munmorah to Vales Point Power Station – Technical Report, contains further details of its findings.

Project: Site trials of novel CO2 capture technology at Delta Electricity

The challenge:

Finding new ways to make the post-combustion capture of CO2 more commercially viable.

The action:

Coal Innovation NSW funded CSIRO Coal Technology to investigate a novel technology to physically separate CO2 from flue gas.

Grant amount:

$616,711 (EOI Round 2009)

The project:

CSIRO Coal Technology received grant funding in 2010 to investigate the ability of a novel, patented technology to physically separate CO2 from the flue gas emitted from NSW coal-fired power stations.

It uses a type of nano-structured Monolithic Carbon Fibre Composite adsorbent material fabricated in a Honeycomb structure (HMCFC absorbent). The promoted benefit of this technology is that it enables dry CO2 capture at room temperature and atmospheric pressure, and in dusty environments with low pressure drop, thereby reducing the operational and maintenance cost of the post-combustion capture process.

The site trials were a world first in demonstrating such solid sorbents on real flue gas. The important experimental data and site operational experience obtained at the power station form a good basis for further development of the technology. The resulting report, Site Trials of Novel CO2 Capture Technology at Delta Electricity, contains further details of the project findings.

Project: Advanced aqueous ammonia-based carbon capture technology

The challenge:

Proving the feasibility of new solvent based post-combustion capture technologies for NSW coal fired power stations.

The action:

Coal Innovation NSW funded CSIRO Energy to further develop and demonstrate the use of ammonia for CO2 capture.

Grant amount:

Up to $2 million (EOI Round 2015)

The project:

This technology uses a cheap, stable and locally available chemical, ammonia, as the absorption solvent to remove CO2, SO2 and other pollutants from the flue gas of power stations and other industries.

The project aims to demonstrate an advanced aqueous ammonia based post-combustion CO2 capture process, developed by CSIRO, and its benefits, through the use of the pilot plant located at Vales Point Power Station.

An additional laboratory stream focuses on the proof of concept and prototyping of an entirely new process to take advantage of the volatility of ammonia to capture CO2, called the “Trimonia Process”.

If successful, the technology could be prepared for large-scale demonstration in NSW, and has the potential to provide a cost-competitive way to remove the CO2 emissions associated with power generation.

Photo of the PCC pilot plant at Vales Point power station, courtesy of Hai Yu, CSIRO

Project: Rotating Liquid Sheet Contactor pilot scale testing project

The challenge:

Improving the effectiveness of post combustion capture processes under real flue gas conditions in NSW.

The action:

Coal Innovation NSW funded CSIRO Energy to design and test a Rotating Liquid Sheet (RLS) contactor for better dispersion and CO2 capture.

Grant amount:

Up to $1.27 million (EOI Round 2015).

The project:

The RLS contractor is a potentially more efficient type of gas separation technology that uses a rotating device to spray out a continuous thin liquid sheet which would contact and absorb the CO2 emitted in the flue gas from a coal-fired power station.

The aim of the project is to validate the design, costs and performance of the RLS contactor in a post combustion CO2 capture cycle, using real flue gas in the pilot plant at the Vales Point Power Station.

If proven, this novel technology could be incorporated into a conventional CCS process and be retrofitted to existing coal fired power stations to reduce their carbon emissions by more than 90%.

The RLS contactor can be considered a ‘platform’ technology, which could be applied to several applications and industries. These ‘spin-off’ applications may even pay for its commercialisation prior to its application to the post combustion capture of CO2.

Laboratory scale Rotating Liquid Sheet contactor (photo courtesy of Leigh Wardhaugh, CSIRO Energy)

Project: Membrane Gas-Solvent Contactor demonstration project

The challenge:

Identifying new technologies to improve the cost-effectiveness of post combustion capture processes to make Carbon Capture and Storage (CCS) more economically viable.

The action:

Coal Innovation NSW funded CO2CRC to develop and trial Membrane Gas-Solvent contactors at a pilot scale to capture CO2.

Grant amount:

Up to $1.21 million (EOI Round 2015).

The project:

CO2CRC is receiving funding to develop and pilot trial Membrane Gas-Solvent contactors, which are a combination of gas separation technologies, for the capture of CO2 from flue gas in a pilot plant at the Vales Point Power Station.

The project will establish the viability of this new hybrid technology and provide the necessary data to enable design scaling to support a potential large-scale CO2 capture demonstration.

The aim of the project is to commission a membrane contactor pilot plant, the largest of its kind in the world, at the Vales Point Power Station to capture 100,000 kg of CO2 per day with up to 20-30% reduction in capital cost when compared to current solvent based CO2 capture systems.

If this can be achieved at scale, it would enable this technology to be cost competitive and help drive down the costs of capturing CO2 for Carbon Capture and Storage (CCS).

Pilot membrane gas solvent contactor in development (photo courtesy of Abdul Qader, CO2CRC)

Project: Third generation membrane material development

The challenge:

Identifying new technologies to improve the cost-effectiveness of post combustion capture processes to make Carbon Capture and Storage (CCS) more economically viable.

The action:

Coal Innovation NSW is funding the University of NSW to develop a new generation of membrane material to capture CO2 and test it under real flue gas conditions.

Grant amount:

Up to $862,803 (EOI Round 2015)

The project:

The University of New South Wales is receiving funds to develop a new generation membrane material and test it under real flue gas condition at Vales Point Power Station.

Membrane technology is a physical separation process like sieving, a technology currently used in the gas industry for separating gas mixtures into constituent gases. A unique feature of this project is that all the materials used for membrane development are commercially available and therefore the process developed in this study is suited to existing large-scale fabrication used in membrane production.

This project has the potential to provide a pathway for translating membrane technology for carbon capture into industrial scale manufacturing in NSW.

Commercial PVDF hollow fibre membranes used as support layer for new generation membrane (photo courtesy of Vicki Chen, University of New South Wales)

Project: Aerosol formation case study

The challenge:

Address knowledge gaps in understanding aerosol formation and possible environmental impacts from the post combustion carbon capture process.

The action:

Coal Innovation NSW is funding the CSIRO to study aerosol emissions from the post combustion carbon capture process.

Grant value:

Up to $687,252 (EOI Round 2015)

The project:

CSIRO Energy is receiving funds to evaluate the potential for aerosols to be produced whilst using a post-combustion capture process on coal-fired power stations.

An aerosol is a colloid of fine solid particles or liquid droplets and the formation of aerosols in industrial facilities can cause serious technical problems for plant operation and can generate compliance issues to meet regulatory requirements.

The aim of this project is to provide an understanding of the potential to generate aerosol emissions to address any knowledge gaps or potential environmental issues associated with CO2 capture plants that use an amine based absorbent.

Post combustion Capture Solvent Degradation Rig used for the aerosol formation case study (Courtesy of Brendan Halliburton, CSIRO)

For further information
Coal Innovation NSW
ccs.info@planning.nsw.gov.au