Long-term partnership with Nynas saves 2 million tons of CO2

22nd February 2024
Partnership stories Industries Chemical & Pharmaceutical

Adven and Nynas refinery in Nynäshamn, Sweden, have been partners for two decades now. A partnership that saves millions – both in money and carbon dioxide. The so-called porcelain wedding is not celebrated with grandeur, but with annual climate improvements.

“Every time we renegotiate the energy agreement, we consider whether we should do it ourselves or continue the collaboration with Adven. Then it takes about three seconds before we realize how much work, capital and time that is required to run this”, Peter Eriksson points out, Technical Manager at Nynas.

Sometimes you have to take a step back to see how the collaboration gets results over time. When Adven took over responsibility in 2004, the company replaced the oil boilers with a biofuel boiler with higher efficiency. Through this, the refinery in Nynäshamn became the first oil refinery in the world mainly powered by biofuel. In addition, Adven built a new district heating network in the municipality, that made it possible to also recover waste heat from the refinery. The shift from fossil fuels has saved 2,000,000 tonnes of carbon dioxide for the energy system in total, a figure that corresponds to 5.5 percent of Sweden’s total emissions in 2022.


The refinery in Nynäshamn is the largest within the Nynas Group. Here, bitumen is manufactured, which is used as a binder in the asphalt on our roads, among other applications. The refinery is also one of the world’s largest producers of naphthenic specialty oils used in several essential industrial applications, including transformers, catalyst and hydrotreatment technology, and industrial lubricants.

Collaboration enables transition

One of the challenges for the energy transition is that industries, aside from energy production, have their core business to focus on. This often means that energy optimization projects are put in the back seat. Adven’s Jonas Dyrke, who has been involved in the collaboration since the beginning, describes the energy partnership as a marriage, requiring trust, confidence, and constant care.

“I have been involved from the start, and I find it to be a very constructive collaboration where we have both given and taken. The spirit has been very positive, and it has developed both of us,” says Jonas Dyrke.

Peter Eriksson laughs and adds, “You have to think carefully about who you choose to marry. You have to invest some time and energy to make sure it is the right one.”

Adven and Nynas collaboration partners in front of Nynas one of the offices at their refinery.
Adven’s Jonas Dyrke, together with Nynas’ Chief Engineering Peter Eriksson and Site Manager Mikael Dahlskog, celebrating 20 years of energy cooperation.

112,000 cubic of water saved per year

In 2018 Adven built a water treatment facility at the site, which boasts two significant advantages. It saves energy, approximately 20 GWh per year, equivalent to one-third of the entire heating demand of Nynäshamn’s district heating network. Additionally, the water purification process saves a considerable amount of water, around 112,000 cubic per year. Since the collaboration began, Nynas has also managed to halve its need for process water, leading to further significant water savings.

“The new water treatment facility saves approximately 112,000 cubic per year, equivalent to the annual water consumption of 600 houses,” Jonas Dyrke estimates.

The water treatment facility utilizes municipal tap water. However, tap water, the same water we drink, is not clean enough to be converted into steam. To purify the water, it needs to reach a temperature of 20 degrees, requiring an increase from the normal 7-8 degrees that water typically maintains in the pipelines. Previously, steam, along with chemicals and flushing water, was used to raise the water temperature.

“We realized that steam at 220 degrees was not necessary to raise the water from 7 to 20 degrees. The residual heat is more than sufficient for that,” explains Jonas Dyrke.

By changing the water treatment system and utilizing the residual heat already available at Nynas, they can use less flushing water. Additionally, Adven no longer needs to produce as much high-temperature steam.

Remote monitoring around the clock

The facility, supplying energy to both the refinery and the residents of Nynäshamn, is managed by Adven’s operational staff and monitored remotely 24/7. The control room maintains continuous communication with the refinery, and in addition, the companies hold regular steering group and development meetings. Operations are optimized daily based on Nynas’ steam requirements and the amount of residual heat generated by the refinery. The electricity price is also crucial, as the facility includes a steam turbine.

For us the most important thing is that Adven specializes in energy, allowing us to focus on what we do best.

Mikael Dahlskog
Site Manager at Nynas

Facts about the collaboration:

  • Through the new energy system, over 100,000 tons of CO2 are saved annually.
  • The environmental improvements have been recognized with 80.8 million SEK for the transition to biofuels and 5.3 million SEK for Adven’s efficient water treatment from the Swedish Environmental Protection Agency.
  • Adven replaced Nynas’ old oil boilers with a 24 MW solid fuel boiler powered by bio- and recycled fuels.
  • The solid fuel boiler can also handle more complex fuels such as sewage sludge, industrial sludge, or slaughterhouse waste when needed.
  • The water treatment primarily utilizes 5 different RO (Reverse Osmosis) filters to purify and filter water efficiently.
  • The residual heat from Nynas is about 40 GWh per year.