Heat grid with industrial residual heat
'Residual heat' is heat that is released from an industrial production process. A residual heat network is an alternative to fossil fuel heating. It consists of a network of well-insulated underground pipes that bring hot water from one place (industry) to another (industry and homes) for various heat applications.
Antwerp North Heat Network utilises residual heat from Indaver's rotary kilns where industrial waste is thermally processed. In a first phase, Antwerp North Heat Network will serve industrial customer Boortmalt, which took a long-term commitment and will use the heat in its malting process. In a second phase, grid operator and multi-utility company Fluvius will link a district heating network to this, allowing schools, public buildings and 3,200 households from two districts in the north of Antwerp to source their heat supply more sustainably. In total, the network has a capacity of about 60 MW. Given this scale, the social importance of this project cannot be underestimated. This heat network is one of the instruments used by the City of Antwerp to realise its urban energy policy. It is part of a city-wide heat network programme (Roadmap 2030).
Indaver realises Antwerp North Heat Network in collaboration with Port of Antwerp-Bruges. In addition to each partner's investment, additional investment grants are necessary for the project to succeed. Both networks can count on Flemish subsidies. The Flemish government encourages the recovery of industrial residual heat for heat networks.
Heat network reduces CO2-emissions by 80.000 tonnes a year
The heat network is implemented in a closed loop. The heat is transferred at a temperature of about 105°C from Indaver to Boortmalt, some 10 km away in the port. Boortmalt uses this heat in the malting process. The cooled water (65°C) flows back to Indaver through a second pipeline to be reused. From the first part of the heat network, a second, so-called 'residential' network goes to social housing, but also to schools and public buildings in the Luchtbal and Rozemaai districts. This is also set up in a closed circuit so that no water is lost. By eliminating the need for Boortmalt and the residential users to use fossil fuels, a significant saving is made on natural gas. The transition from fossil fuel to waste heat also means a reduction in CO2 emissions of 80,000 tonnes per year (when the full capacity of the heat network will be utilised). This corresponds to the annual emissions of 25 000 Antwerp households.