Recycling experiences from Scandinavia, focus on ash from waste incineration and plastics

Paper in proceeding, 2019

Ash from waste incineration generated when cleaning flue gases contain about 40 w% of water soluble salts, most containing heavy metals like Pb. A method to use the acid scrubber liquid from the air pollution control system to neutralize the alkaline ash has been developed and a full scale demonstration plant is presently being built in Copenhagen, Denmark. The project has partly been financed by EU LIFE. The plant includes steps for metal recycling, mainly Cu and Zn, and removal of chlorides from the washed solid fraction that could be used for construction purposes. Stena Recycling International finance a Professorship in Industrial Material Recycling at Chalmers Technical University in Gothenburg Sweden since more than 10 years back, where most of the research in this area takes place. Not all thermoplastic waste fractions are clean enough to be mechanically recycled. Feed stock recycling, substitutional fuel and energy recovery are possible alternatives that have been evaluated and tested in Europe. Halogens are in general the biggest challenge since they produce corrosive acids when decomposing due to increased temperature. In a more Circular Economy materials are material recycled more often than today. No sorting equipment is 100 % correct why low concentrations of contaminants will be able to detect in many recycled materials. Bio test is one efficient method to prove that even though contaminants can be detected the bio availability could be very low. Gene response monitoring has successfully been applied.