Årdal plans to build a waste incineration plant based on new technology to capture and store CO2, removing greenhouse gases from the atmosphere.
For over 15 years, SINTEF has gradually developed its expertise in the field of oxycombustion, using pure oxygen instead of air to drive the combustion process. Using oxygen has many advantages. Especially the fact that his emitted CO2 can be recovered more easily.
SINTEF was recently involved in a joint project with the municipality of Årdal in Vestland county to build the world’s first waste incineration plant that not only uses oxygen for combustion but also provides carbon capture and storage (CCS). The project he named NETOX is currently in the application stage. Today, a large amount of waste generated in Norway is transported to Sweden, where it is incinerated to fuel district heating plants.
In fact, we are actually removing CO2 from the atmosphere.
“First, it will take two to three years to design and build a demonstration plant,” says Mario Ditaranto, a researcher at SINTEF Energy Research.
“Then we have to demonstrate that the technology works and is commercially viable,” Ditalant says. “If all goes well, we will be able to build an industrial-scale plant that will be operational in 2030 and will be the world’s first demonstration of waste incineration using oxy-combustion,” he says.
“A full-scale plant would be located in an industrial area, close to a city, that would generate a lot of waste and ideally would also produce hydrogen,” Ditalant says.
When it becomes expensive to emit CO2, it becomes more profitable to reduce emissions.
not yet mature
Initially, the project considered building a demo plant at the existing Haraldrud recycling facility in Oslo. However, the target deadline for reducing CO2 emissions has caused the city of Oslo to value more tried and tested technologies.
“So far, we have demonstrated that oxycombustion works for a variety of waste-like mixtures,” Ditalant says. “We have also performed a simulation of a waste incineration chamber and successfully reproduced the temperature using this method. However, more time is needed to design the combustion technology and optimize the oven. We’ve come a long way, but the technology is not yet mature enough to translate to industrial scale for many years,” he says.
This will be the world’s first demonstration plant for waste incineration using oxygen combustion.
An advantage of locating the plant in Årdal is its ideal location close to hydrogen production using renewable energy with oxygen as a by-product. Additionally, local authorities have some experience with waste incineration.
Flexible combustion with benefits
Our waste consists of all kinds of things. It also depends on the location and volume. Optimal incineration is difficult to achieve due to lack of homogeneity, but oxycombustion has the great advantage of being adaptable to a wide variety of fuel types. In addition, regardless of the type of garbage, it is possible to optimize combustion with a little ingenuity.
“Replacing air with oxygen to burn certain types of fuels results in very high combustion temperatures – too high, in fact, for ovens and boilers,” Ditalant explains. “But if he supplies the CO2 that is recirculated from the flue gas in this process, it lowers the temperature and allows combustion at normal temperatures. This is what we call ‘oxycombustion. ’ he says.
“Imagine some waste, such as water-saturated waste, that is harder to burn than most,” Ditalant says. “With a little less CO2 recirculation, the temperatures are somewhat higher than with air alone. Higher temperatures also mean more efficient combustion,” he explains. .
A disadvantage of oxycombustion is the cost associated with the production of oxygen. But Ditalant believes another eco-friendly technology could soon come to the rescue.
“Many engineers see hydrogen as the fuel of the future, but at the moment it remains expensive to manufacture.
Oxygen is a by-product of hydrogen production. There is currently no demand for this gas, but if it could be sold to waste incineration plants, it would make hydrogen production more profitable and access to oxygen cheaper. In this way, two eco-friendly technologies can complement each other. However, much work is still needed to clarify the economics of such synergies.
A factor that could help level the economic valuation is the skyrocketing CO2 emissions tax. When it becomes expensive to emit CO2, it becomes more profitable to reduce emissions.
CCS and bio-CCS
Norway is committed to reducing CO2 emissions by 55% by 2030 and 90-95% by 2050.
“It’s hard to imagine how this could be achieved without carbon capture and storage,” Ditalant says.
All CO2 generated by incineration at the Årdal pilot plant will be captured and shipped for storage. The project aims to link its operations to the Norwegian state’s Langskip (Longship) CCS project, which involves sequestering CO2 in subseafloor reservoirs in the North Sea.
“This is actually a carbon negative initiative, also known as Bio-CCS,” says Ditaranto. “Biomass extracts CO2 from the atmosphere. By burning this biomass and capturing and sequestering all the resulting CO2, he is actually effectively removing it from the atmosphere,” he says. says.
competing technology
Major players such as Hydro, Yara, Elkem, Norcem and Oslo Municipality are currently working on various CCS projects. But Mario Ditalant isn’t concerned that the more established technologies being developed as part of these initiatives will replace oxycombustion.
“You should have a variety of tools in your toolbox,” he says. “All technologies have advantages and disadvantages. The great advantages of oxyfuel combustion are its flexibility, its ability to adapt to all types of waste, and the ease with which he can capture CO2 from the combustion process,” he said. say.
Original: New approach to waste incineration removes CO2 from the atmosphere
Than: Sintef
