Demonstration plant for carbon capture 2023-2024

After trials on a smaller pilot plant in 2021-2022, ARC is following up with a larger demonstration plant that can capture up to 4 metric tons of CO2 per day. The demonstration plant was commissioned in late 2023.

Test of carbon capture on waste incineration

Through an EUDP-supported project, ARC, together with DTU, Pentair and Rambøll, is investigating how carbon capture is best connected to waste incineration, and whether it can be made energy-neutral by using heat energy from the carbon capture process for district heating.

Carbon capture is particularly interesting in relation to energy utilization of waste, as it is possible to capture large amounts of biogenic CO2, whereby a plant can help to actively lower the total amount of CO2 in the atmosphere. Roughly two-thirds of the CO2 discharge from Amager Bakke consists of biogenic CO2.

The challenge of connecting carbon capture for a waste-to-energy plant is, however, that there are many variations in the composition of the flue gas that come from energy utilization of waste, as the waste brought to the plant is varied. This means that a carbon capture plant connected to waste energy must be able to handle changes without affecting efficiency.

The trials on a small pilot plant in 2021-2022 were very promising in terms of the efficiency of capture. A decision has therefore been made to continue them. In late 2023, we have commissioned a larger demonstration plant with a capacity of capturing up to 160 kg per hour. The plant is designed to verify the results obtained from the pilot plant. Fewer solvents will be tested, but they have to remain in the plant for a longer period. How a simulated connection to the district heating network will affect carbon capture will also be studied. Captured CO2 will be pressurised and condensed into a liquid which will be used for various practical purposes.

At the demonstration plant, the purpose is to:

  • reduce the energy requirement (electricity/steam) even more than we achieved in the pilot plant
  • learn more about the technology so we can build the best-possible full-scale plant
  • simulate the connection to the district heating network – to make the most of the surplus heat from the capture process.

The demonstration plant resembles in every way a full-scale plant, although of course it is much smaller.

Demonstration plant versus pilot plant

Demonstration plant 2023
Primary purpose
Simulation of district heating integration
Operating type
Stable, constant operation
Capture capacity
160 kg CO2 per hour
Energy consumption
2.6 GJ/per metric ton CO2 or lower
What the CO2 is used for
Used for research and commercially
Test period
2023-2024

Pilot plant 2021
Primary purpose
Testing of solvents (capture fluids)
Operating type
Stop and start
Capture capacity
20-40 kg CO2 per hour
Energy consumption
down to 2.6 GJ/per metric ton CO2
What the CO2 is used for
Not collected, research only
Test period
Sept. 2021- Apr. 2022

Find out more

You can read more about carbon capture, ARC’s project and results in the articles below:

The pilot plant for carbon capture was operational at ARC until April 2022. The aim was to test if CO2 can be captured from flue gas from a waste-to-energy plant and gain practical experience with carbon capture technology. The pilot studies was the first of their kind at a waste incineration plant.

This research article summarises a number of the experiences gained from the project. Such experience is relevant to future experiments with carbon capture technologies.

This research article deals with whether the completed carbon capture process at the pilot plant at ARC has led to any unwanted emissions.

CO2 capture process takes place by capturing CO2 in the flue gas with an amine-based solvent. The solvent is broken down over time due to impurities in the flue gas. Experience from the pilot plant at ARC shows that the breakdown can lead to unwanted emissions, e.g. from flue gas, and also consists of corrosion products. Installing a filter to clean the solvent of impurities fixed the problem.

The technology to capture CO2 and then transport it to either underground storage or for use in PtX (as a basis for the development of green fuels) is ready to be implemented.

This research article points out that there is a lack of global harmonization of the framework for the entire value chain from capturing CO2 until it has been transported further for storage or use. A standardization of the quality of CO2 is particularly urgent. The higher the requirements, the higher energy consumption in the process of capturing and purifying CO2. On the other hand, it becomes cheaper to transport and store. Coordinating this worldwide to reduce costs throughout the value chain is necessary. A CO2 infrastructure and storage capacity across national borders is also required – as CO2 does not respect national borders.

Degradation and emissions of amine-containing solvents from CO2 capture plants are important to address as we are getting closer to full-scale deployment. This article describes solvent degradation and air emissions from CO2 capture with 30 wt% monoethanolamine (MEA) on the pilot plant treating flue gas from a ARC. The release of nitrosamines and nitramines was shown to be below the detection limit. Preliminary results showed that the installation of an acid wash removes gaseous degradation products from the depleted flue gas by up to 83% for MEA.

This article contains an overview of the data gained from the pilot plant. The pilot is fully automated, and the process control structure helps achieve multiple steady states at regular intervals. In addition, the pilot is capable of several configurations which can assist in optimising the energy required for solvent regeneration. The article discusses the base case configuration of the pilot plant by employing 30 wt% MEA as the solvent. Experiments were conducted to analyse the influence of reboiler duty, solvent flow rate, and gas flow rate on the pilot’s performance. The influence of these parameters on several aspects is discussed in detail, and recommendations for the optimal operation of such plants are provided.

How does carbon capture work?

ARC aims to become the first CO2-neutral waste energy plant. One of the key elements will be capturing carbon from flue gas. The technology itself is well  known: CO2 is captured by a chemical process in which the CO2 molecules are washed out of flue gas and bound in a liquid.