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Industrial symbiosis in Kalundborg

The municipality of Kalundborg in Zealand, Denmark, has a total population of 49 743. The municipality is predominantly rural with a few small urban agglomerations. The major economic activities in Kalundborg are industry, construction, and agriculture.

Distribution at the Industrial Symbiosis. Photo: Rasmus Ole Rasmussen

Distribution at the Industrial Symbiosis. Photo: Rasmus Ole Rasmussen

The Industrial Symbiosis (IS) grouping of businesses in Kalundborg was formed into a cluster of industries focused on increasing groundwater protection. This was supported in the early 1980s by the county of Western Zealand. The defining concept here was that one company's by-product becomes an important resource for one or several of the other cluster-members. The outcome was cost reduction and resource-savings as well as environmental protection.

Kalundborg's IS is a network of seven companies: Dong Energy Asnæs Power Station, the plasterboard factory Gyproc A/S, the pharmaceutical plant Novo Nordisk A/S, the enzyme producer Novozymes A/S, the oil refinery Statoil-Hydro A/S, the recycling company RGS 90 A/S, the waste company Kara/Noveren I/S and Kalundborg Municipality.

Current projects deal with water recycling, the transfer of energy and the recycling of waste products between the independent symbiosis partners. They also benefit financially from the co-operation because the entire project is based on commercial principles. At present the network has 6 energy-exchange projects, 12 on water recycling and a further 8 on the recycling of waste products.

Excess heat from the Asnæs Power Station is distributed to the town of Kalundborg through a district heating network. Steam is provided to Statoil, Novo Nordisk and Novozymes for industrial processes. Reductions in the level of water demand have been achieved by treating waste water, including the recovery of sulphur from the combustion process at Asnæs Power station, which again is used for the production of gypsum and plasterboard. Furthermore, by-products from the yeast fermentation process from the production of insulin at Novo Nordisk are used in the production of fertilizer.

The planning and establishment of the initial IS was carried out by the directors of three large processing industries in Kalundborg: Dong Energy, the pharmaceutical company Novo, and the oil refinery, Statoil, all familiar with each other and their companies. The level of trust existing between the parties was an important factor here because it facilitated the development of the network, which in turn served as the baseline for the reaching of agreements between partners.

The Kalundborg IS has attracted both international attention and R&D investments as well as becoming a model for other regions. Today, the Kalundborg Symbiosis Institute coordinates the activities of the network.