Abstract

Due to environmental and economic concerns, there has been a large push to investigate recycling applications for automotive paint sludge. Automotive paint sludge is considered a nuisance and hazardous waste material within the automotive industry around the world. The focus of this project was to investigate and develop a recycling application that would employ the use of the automotive paint sludge material as received. The paint sludge was used as a binder for iron ore pellets, typically used for iron- and steelmaking. The development of the type of recycling application conducted during this project was aided by a review of different binders used in iron ore pellets, as well as the various techniques used to recycle automotive paint sludge materials. Two different paint sludge samples were characterized by their organic and inorganic components. It was then determined to be a possible substitute for the standard iron ore pellet binder: bentonite clay. Unlike bentonite, paint sludge has half the concentration of silica and alumina, which are detriments in the ironmaking process. Iron ore pellets were made using magnetite ore, 1.0–3.0 wt.% limestone, 0.0-1.0 wt.% bentonite, and 0.0-1.0 wt.% paint sludge from two different paint shops. The pellet recipes were evaluated via a statistical analysis software where low, middle and high material weight percentages were output to ensure optimized results. The iron ore pellets with paint sludge material as a binder were then tested for their standard physical and chemical properties to make sure they were comparable to pellets made with bentonite clay. It was concluded via the physical and chemical property tests that iron ore pellet made with paint sludge material with this patent pending technology were just as capable of withstanding typical transportation and handling used in the iron- and steelmaking industries.

Keywords:Paint sludge; Steelmaking; Iron ore pellets; Limestone; Bentonite