Manufacture of construction components with plastic fraction of WEEE recycling waste

Abstract

Waste electrical and electronic equipment (WEEE), have grown significantly in quantity in recent years and this trend is expected to continue. The plastic waste fraction (RPF) constitutes approximately 30% of the total weight, and has not been able to be inserted into the recycling circuit, due to the heterogeneity of constitutive plastics and the presence of contaminants, mainly flame retardants and metals heavy, both toxic to human health.
There are numerous studies on the addition of plastics to mortars, acting as filler material or reinforcing fibers, achieving materials with aptitude for this use. The study of these antecedents led to consider the use of RPF as an aggregate in mortars, in total and partial replacement of the traditional aggregate.
A synthetic aggregate (AS) was developed through the core-shell strategy, in which the plastic core is coated with successive layers of cement and its performance as a construction component was studied by means of mechanical resistance tests and determination of physical properties. AS can be used in mortars in total an d partial replacement of fine aggregate, without significantly decreasing mechanical strength. Despite the good results obtained over time, yellow exudates appear on the surface, as a result of the destabilization of flame retardants in the basic medium ofcement, which makes it potentially dangerous for use in civil constructions. To reverse this effect, activated carbon (CA) was added to the process as a stabilizing additive. The chemical analysis showed a very good stabilization of the
contaminants when using 3% CA by weight. To evaluate the effect of CA with cement setting, this work presents the results of the use of different types and dosages of CA.