Finspångs Tekniska Verk (FTV)
Sometimes, all it takes for an environmental scoundrel to become a community-friendly recycler is a bit of willpower and a control system from Prevas. This is a story about how Swedish Steel AB (SSAB) in Finspång, Sweden, stopped blowing 10 MW of heat out to air and instead started injecting it into the municipality’s district heating network.
Assignment: Modern control system.
Unfortunately, spray painting results in a fair amount of spillage. Paint that doesn’t end up on the item being painted must be taken care of. The standard method is to burn the surplus paint and since it contains solvents it burns well, giving off lots of heat as a byproduct. The only snag remaining is to harness that heat. Up to the end of 2012, SSAB Sheet Steel in Finspång was wasting that heat, but as a result of cooperation between SSAB and the municipality’s Technical Services Department, most of that energy is now made use of.
Anders Kvist, Business Area Manager for energy in the department says: “We have ‘always’ known that the heat has been there with SSAB and the idea of taking care of it has been with us, semi-consciously, for quite some time. There is a similar facility in Borlänge and we know, of course, how they recover the heat there.”
Prevas was perceived of as a natural partner for the programming of the new heat harnessing facility since the company acted as consultants for the programming of SSAB’s other facilities. We actually instructed the main contractor, YIT to use Prevas. The next project will be run in the same spirit. A long-term goal of Finspång’s Technical Services Dept. is to be totally oil-free by the year 2020 and this heat capping facility is an important step in that direction, says Kvist.
Anders Birgersson is a programmer and systems integrator at Prevas and has participated in the design of the heat recovery system. He says: “The hot flue gases from the combustion furnace ends up on the roof and it was easiest to build the facility above the in-loading bay of the paint store and put the gas-cooling heat exchanger, the control equipment and the hot-water pumps there. The temperature of the flue gases, as they reach the cooler is approximately 700°C, which is perfectly adequate for raising the heating water temperature to 95°C without further measures. In this way some 600°C are removed from the flue gases. For obvious reasons, the need for heating in Finspång varies widely with the time of day and the season but here is an important resource that can be switched into the network when it is needed. Not only the Finspång community derives benefits from the new facility, even SSAB’s own premises are hooked onto the network and kept habitable in part thanks to the new heat recovery installation.
Prevas has delivered a control system with built-in control concepts and an operating panel for local attendance. The main contractor was YIT, who selected hardware, regulatory control components and designed the overall installation. In addition to programming, Prevas also performed configuration, commissioning and tuning. The control system has also been integrated into the distributed control system, type 800xA from ABB, used by Finspång’s Technical Services Dept. For this, Prevas used existing program modules provided by Technical Services. The result is that the operators in Technical Services’ heating station are able easily to control the heat supplement from SSAB as a natural part of their regular attendance duties.
“The 6-7 MW of power, so far extracted from the new installation, is a direct replacement for the fossil fuel Technical Services previously burnt to heat the municipality. The sustainability argument is a weighty one for Swedish municipalities since they all want to get away from heating oil and get their heating from other sources, e.g. from waste heat which industry is unable to make use of”, concludes Birgersson.
Do you want to know more about this project or find out what Prevas can do for you, please contact us.
Sebastian Johansson, e-mail