In Linköping, Sweden, the optic bag system has also been operated
by a waste collection company called Tekniska verken. About
80% of the domestic households in this city have adopted the optic
bag system (Book, 2014). Fig. 2 illustrates a simplified flow diagram
for separating the optic bag from other bags in an optical
sorting plant operated by the Tekniska verken company. Based
on the performance of the optical sorting plant, the food waste
fraction can be collected with a high level of purity, with an
optimum separation efficiency of 98% (Tekniska verken, 2012).
Optic bags that are not detected accurately or any loose materials
that pass through the optical sorting system are treated as residual
fractions