Kalundborg – Industry park

In Kalundborg, the biggest inter-connected industry park in Denmark is placed, where a partnership between 11 public and private companies has created a symbiotic network benefitting both the environment and the economy of the involved parties. The large project called Kalundborg Symbiosis started in 1972, and the main principle is that residues from one process become a resource in another process. This is done by circulating materials and resources between the companies to improve the reutilization, save money and minimize the amount of waste. The project focuses around sharing and recycling three types of resources:

Energy: Steam, electricity, heating and natural gas
Water: Wastewater, surface water, cooling water and supplementary water
Materials: Waste, gypsum, fly ash, sulphur, sand, sludge, biomass and manure

One of the big partners in the project is Ørsted which owns a power plant called Asnedsværket, which produces electricity for the electricity grid and heat for the district heating grid in Kalundborg. Further, they deliver gypsum（石膏） to a company called Gyproc, which is a byproduct derived from sulphur through the cleaning of flue gas at the plant. The plant is also in a process of replacing coal for heat and electricity production with biogas and biomass as transition fuels in the green transition. The materials used for producing gypsum at Gyproc consist of up to 85% recycled materials and ensures both materials at a high quality and at competitive prices. Gyproc delivers process heat to the district heating grid as well.

Novo Nordisk, who produces 50% of the insulin( 胰岛素) used worldwide, is another partner in the symbiosis project. The company benefits from the large amounts of water and energy available locally, which improves the sustainability of the chemical products. To contribute to the symbiosis, Novo Nordisk delivers residual products suited for the production of manure and biogas, which is used by a biogas company in Kalundborg. An illustration of the symbiosis between the companies in Figure 4 shows the flows of energy, water and materials between the included companies.