Aenert news. Industrial tours
Amager Bakke, also known as Copenhill, is a combined heat and power waste-to-energy plant and a 85 meter tall recreational facility in Amager, Copenhagen.
Amager plant has two biomass-fired blocks: 250,000 tonnes of wood pellets and 1 million tons of wood chips per year. For each ton of waste, Amager Bakke can produce 2.7 MWh of district heating and 0.8 MWh of electricity. This enables for 670,000 Copenhageners and almost 70,000 business customers to get district heating from Amagerværket.
The recreational components of the facility opened in December 2018, with an attendance estimated at 42-57 thousand visitors annually. Almost 3,000 m2 of the roof surface is arranged as an exciting green landscape, which encourages visitors to explore the site's possibilities and find multiple paths through the park. The ski slope on Amager Bakke is Denmark's largest ski hill. At 80 meters high, the climbing wall at Amager Bakke is the highest artificially constructed in the world.
Table of Contents
Activities at Amager Bakke
The rooftop park
The ski slope
Climbing
Process of handling residual waste at Amager Bakke
1. Residual waste arrives
2. Dry and wet residual waste is mixed in the silo
3. In the ovens, the energy from the residual waste is generated
4. Slag and fly ash
5. Steam is produced in the boilers
6. Turbine and heat exchangers
7. Flue gas cleaning
8. Water treatment
The Danish government is working towards Copenhagen becoming the world’s first carbon-neutral capital city by end of 2025 by implementing impactful CO2 reduction initiatives.
The ARC Amager Bakke Waste-To-Energy plant or Amagerværket has a decisive role in Copenhagen's ambition to become the world's first CO2-neutral capital.
Amager Bakke, also known as Copenhill, is a combined heat and power waste-to-energy plant and a 85 meter tall recreational facility in Amager, Copenhagen.
The facility opened in 2017 and partially replaced the nearby old incineration plant.
Activities at Amager Bakke
The recreational components of the facility opened in December 2018, with an attendance estimated at 42-57 thousand visitors annually.
The rooftop park
On the rooftop park there is multiple exploration opportunities. One can run, hike, play or enjoy the view and follow the activities on the hill.
Almost 3,000 m2 of the roof surface is arranged as an exciting green landscape, which encourages visitors to explore the site's possibilities and find multiple paths through the park.
The green installations are manifested in the concept "10 places and 10 routes", which was developed together with the Local and Infrastructure Foundation.
The 10 locations contain a number of slopes and breathing spaces on the roof surface, where guests can look out over the hill, take a break and exercise.
On the other parts of the roof, and on the associated escape route stairs, there are 10 varying walking and running routes, which include everything from an inspiring walking landscape to short sprint routes and longer challenging training routes. Some of the routes are integrated into the adventurous landscape on the roof surface, where in places visitors can jump from rock to rock to get there. It provides a challenging and different running experience than the one a runner normally gets when running in a park.
In front of Amager Bakke there is a toboggan and ski playground, where freestyle enthusiasts can train, and beginners can test their skills on skis.
The ski slope
The ski slope on Amager Bakke is Denmark's largest ski hill.
With 530,000 active athletes nationwide, skiing is a major sport in Denmark - despite the fact that the prerequisites for training and practicing the sport in the country are extremely modest. Amager Bakke is a supplement to Sweden, Norway and the Alps.
Amager Bakke is an important offer for the many alpine skiers in the region who would otherwise have to go to Sweden, Norway or the Alps to ski.
According to the Danish Ski Association, the ski hill is a landmark for the many Danes who ski every year - and not least for the 17,000 organized members in the approximately 80 Danish ski clubs.
The Ski Association sees perspectives in the ski slopes – both in terms of training and physical development – but also because skiing is traditionally an expensive sport.
For the association's elite athletes, several of whom take part in the Olympics and the World Cup, the hill ensures activities and training throughout the year, the organization's instructor and trainer courses and a permanent training/power center that gives the athletes a permanent sense of belonging and extended opportunities to win medals for the country.
As Denmark does not have a tradition of developing and designing ski facilities, world's leading ski hill designers have contributed to the development of the recreational facility. This has been particularly important, as the "mountain" was built of concrete, and the geometry can be changed minimally after the building itself has been erected.
The building itself is divided into four separate slopes, each with its own lift system. The two lower slopes are categorized as green and have a slope of 14 and 18%. The third descent is blue, with a slope of approx. 25% and the last one is red/black with a slope of 20-45%. Although the slopes have different colour categories, the entire ski area on Amager Bakke is covered with green artificial snow mats.
The three lower descents are equipped with conveyor belts that take visitors up to the start of the descent. The conveyor belts are especially good for beginners as they are easy and safe to use. The final descent gets its own plate lift as it is too steep for conveyor belts.
Climbing
The sport of climbing is one of the fastest growing sports movements in Denmark.
At 80 meters high, the climbing wall at Amager Bakke is the highest artificially constructed in the world.
The climbing facilities inspire an active lifestyle and hopefully attract more visitors to the sport of climbing. At the same time, the climbing wall offers experienced climbers a real challenge.
Process of handling residual waste at Amager Bakke
Amager plant opened in the spring of 2020 its biomass-fired power plant block AMV4, which thus has two biomass-fired blocks:
1. AMV1, which uses approx. 250,000 tonnes of wood pellets per year
2. AMV4, which uses approx. 1 million tons of wood chips per year
Since 2020, the entire production of electricity and heat at Amagerværket has been based on renewable energy in the form of documented sustainable biomass.
This enables for 670,000 Copenhageners and almost 70,000 business customers to get district heating from Amagerværket.
In the following section, you can see what happens to residual waste and how the facility within Amager Bakke works.
1. Residual waste arrives
ARC manages almost all aspects of waste handling in Copenhagen, starting with receiving residual waste from citizens and businesses, and supplies electricity and district heating back to the city. Approx. 50% of the residual waste that Amager Bakke receives from its owner municipalities comes from private homes, the rest from businesses.
Every day, 250-300 tonnes arrive with waste that must be weighed and registered. Approximately 5% of the tonnes are sampled to ensure that the waste is suitable for incineration. There is thorough process to check whether the waste is sorted properly and that it does not contain things that can damage the facility or that are toxic.
2. Dry and wet residual waste is mixed in the silo
In the unloading hall, the residual waste is tipped directly into the silo, which is 30×50 meters and has a total height of 36 meters. The silo can hold approx. 22,000 tonnes of waste – this corresponds to three weeks' worth of waste from municipalities. Two automatic grabs ensure that the residual waste is mixed so that it is uniform. That the waste is uniform is important for the combustion process to be as stable as possible. Therefore, it is also not good if the silo is more than half full, because then the grabbers cannot mix properly.
When the residual waste is mixed, the grabbers lift it into the firing funnels for the ovens. Each grab can lift up to 15 tons of waste. In order to reduce odors from the waste, there is negative pressure in the unloading hall. The air that is sucked out of the hall is used in the ovens.
3. In the ovens, the energy from the residual waste is generated
Amager Bakke's two identical kilns have a capacity of 25-42 tonnes of waste per hour. When the waste is filled in the hopper, it falls down through the waste chute. Here it forms an airtight plug, so there is always a negative pressure in the oven. The bottom of the oven slopes downwards and is composed of 24 rows of perforated steel plates. Each row is movable and forms a large undulating carpet, called the grid carpet. As the debris moves forward, it gradually ignites. It takes 1.5-2 hours to burn the waste in the furnace, and it takes place at a temperature of 950-1,100 °C. The temperature is controlled by blowing air through the holes in the grates. When the waste has reached the end of the grate, virtually all energy is released as hot smoke.
For each ton of waste, Amager Bakke can produce 2.7 MWh of district heating and 0.8 MWh of electricity.
4. Slag and fly ash
When the residual waste is burned, 17-20% by weight remains as slag. The slag consists of ash from the waste, gravel, sand, metals and other materials that cannot burn. The slag is collected in a separate slag silo and transported to a sorting facility. Here it is turned and watered for 3-4 months. This process is called maturation. The purpose of the maturation is to get particles from heavy metals to bind to the slag particles so that they cannot be washed out. After maturation, metals are sorted out for recycling. For every 200 kg. slag, 10-15 kg of metal can be sorted out, which can be reused. The slag is then harped (sieved) so that it has the same properties as stable gravel, and can be used for filling in building and construction projects.
The fly ash, which is removed from the smoke in the plant's filters, contains high concentrations of heavy metals and other trace elements. The substances originate from waste that has not been sorted correctly, e.g. batteries. The fly ash and other by-products from smoke cleaning are used as a substitute for lime to neutralize residual products from other industries. The mixture acquires a cement-like hardness and is used to recreate the landscape of a disused limestone quarry.
5. Steam is produced in the boilers
Amager Bakke has two boilers, each of which consists of a box with a large amount of tight-fitting pipes through which water flows under high pressure. The ovens are built together with each boiler, so that the hot smoke from the oven rises and transfers its heat energy directly to the water in the pipes. A pump ensures that a high pressure is maintained in the pipes, so that the steam produced has a pressure of 69 bar and is 440 degrees hot. Each boiler can produce up to 137 tons of steam per hour. The steam from both boilers is collected in a common steam pipe, called a steam rail, from here the steam is led on to the steam turbine. In order for both ovens and boilers to expand when they get hot, they do not stand on the floor, but are instead suspended from the steel structure in the ceiling.
90% of the energy in the waste is converted into high-pressure steam.
6. Turbine and heat exchangers
The electricity and district heating are made during stage. A steam turbine is made up of a series of paddle wheels mounted on a shaft. As the steam expands through the impellers, kinetic energy is created and the shaft begins to rotate. The shaft is connected to a generator, which converts the energy into electricity. Electricity production is up to 63 MW.
When the turbine has taken the pressure and heat from the steam, there is still heat energy left. That energy is used in the district heating exchangers. District heating water is heated in the heat exchangers, which is sent out into the district heating network. When the heat in the water has been used up by the consumers, the water is sent back and heated again. District heating production is up to 247 MW.
At Amager Bakke, the production of electricity and district heating can be adapted to the needs of consumers. If a lot of electricity is needed, all the steam is directed through the turbine. If, on the other hand, there is a need for a lot of district heating, the steam is led around the turbine and directly into the heat exchangers.
7. Flue gas cleaning
When the smoke has passed through the boilers and given off its heat, it must be cleaned. Each furnace line has a separate smoke cleaning system, which consists of an electric filter, a catalyst, three scrubbers and a dust filter.
Amager Bakke is also the first waste-to-energy plant in Denmark to be equipped with a catalyst to remove NOx.
The electric filter removes most of the dust and ash in the smoke, what is called fly ash.
The smoke is then passed through the catalyst, which removes Nox:
1. The first scrubber removes hydrochloric acid, mercury and other unwanted substances
2. The second removes sulphur dioxide using lime
3. The third scrubber is a so-called condensing scrubber. Here, water vapor is condensed into water droplets, so that residual heat in the smoke can be utilized with the help of heat pumps. The residual heat is sent via heat exchangers into the district heating network. In total, approx. 20% of the district heating production from the heat pumps, which are connected to the smoke cleaning.
The final cleaning step is a wet dust filter, which removes the last traces of dust in the smoke.
Before the cleaned smoke reaches the chimney, it passes a measuring station which constantly records the content of pollutants. In this way, ARC ensures that all environmental requirements are met.
Amager Bakke including the chimney is 123 meters high. It contains three separate chimney pipes: one for each of the two furnace lines, and one for an emergency power generator.
8. Water treatment
ARC cleans the water from the waste. Waste contains a lot of water, and therefore a lot of water vapor comes out when you burn it. Most of the water is collected in the smoke cleaning. At full load on the two furnaces, up to 13 m3 of waste water is produced per hour. The waste water has to start with a pH value of between 0.5 and 2.5 and its purification and neutralization takes place in four stages:
- In the first cleaning stage, lime and lye are added, which neutralize the waste water to a pH value of between 7 and 8.
- In the next stage, particles settle in the water as sludge in large tanks. The wet sludge is passed on to a filter press, where most of the water is pressed out. The sludge is collected in a container and deposited together with the fly ash.
- In step three, the water is passed through some sand filters and ammonia strippers. Here, the smaller particles that were not previously settled are filtered out. The excess ammonia in the ammonia strippers is recycled for smoke cleaning.
- The final cleaning stage consists of carbon filters and ion exchange. Here, the water is cleaned of the last remnants of organic materials and metals.
Overall Amager Bakke supplies customers with energy around the clock, all year round.
The entire energy plant is in operation 24 hours a day, 365 days a year. The entire process is monitored around the clock – from weighing to water treatment. Via a Control, Regulation and Monitoring system (SRO), which contains approx.10,000 alarm points and visual systems, employees in the control room monitor the entire process.
Finally, a key focus at Amager Bakke is capturing CO2 from the flue gas. CO2 capture at waste-to-energy plants can become an important tool in the fight for the climate, as approximately half of the fuel is CO2-neutral. This means that the catch will thus actively help to lower the total amount of CO2 in the atmosphere.
VISIT COPENHILL
At CopenHill, you can experience countless exciting activities for the whole family. Amager Bakke operates as a free space for everyone that loves being active together.
Text by Ion Ciorici and Jana Janicka. Photos by Ion Ciorici