Kent D. Peaslee

Study of spent refractory waste recycling from metal manufacturers in Missouri

There are over 150 metal related companies in Missouri that discard approximately 7500 metric tons of spent refractories annually. Nearly all (∼99%) of the refractories are landfilled wasting valuable natural resources. The purpose of this research is to minimize the refractory wastes being landfilled by studying the types and quantities of spent refractories generated by these companies, the states of these wastes, and technologies for recycling and reusing them. Conducting this study in Missouri is ideal because it has a diverse group of metals (lead, aluminum, steel and copper) manufacturers and the results, therefore, should be applicable to other regions of the US and of the world. This paper reviews previously identified techniques for recycling refractory materials, summarizes data from informational surveys of metals manufacturers in the state, and highlights potential barriers to, and opportunities for, spent refractory recycling. Results from the surveys indicated that two large waste streams exist in Missouri and that identifying and implementing recycling of these two waste streams would dramatically reduce the quantity of spent refractories landfilled annually.

Detection of Non-metallic Inclusions in Steel Continuous Casting Billets

This work applied automated particle analysis to study non-metallic inclusions in steel. Compared with traditional methods, the approach has the advantage of capturing the morphology, measuring the size, recording the original positions, and identifying the composition of inclusions on a selected area in a short time. The morphology and composition of typical inclusions were analyzed using partial acid extraction and discussed through thermodynamic calculation. Steel samples were collected from the entire cross section of billets cast during times of steady state and ladle change. The spatial distribution of inclusions agreed well with the measurement of the total oxygen. The spatial distribution of inclusions was plotted to represent the entrapment positions of inclusions on the casting strand and their concentration on the cross section of the billet. Also, regarding the different size and type of inclusions, the spatial distribution of classified inclusions was explored such as the distribution of sulfide, oxide, and high sodium and potassium content inclusions. The sufficient information could be used to identify the source of inclusions and guide the steel refining process.

Characterization and Recycling of Spent Refractory Wastes from Metal Manufacturers in Missouri

Approximately 7500 t of spent refractories are landfilled annually in Missouri. Research was initiated to reduce the amount landfilled by studying the types and quantities of spent refractories generated, the conditions of the wastes, and technologies for recycling and reusing spent refractories. This paper reviews the characterization results from three major spent refractory waste streams in Missouri and evaluates beneficiation and recycling. The results indicate considerable promise in reusing spent doloma refractories as a soil conditioner and spent alumino silicate refractories as a raw material for production of Portland cement. The amount of spent refractory wastes landfilled in Missouri could be reduced by an estimated 50% if these techniques were adopted. Attempts to recycle spent high alumina refractories as aggregates for castables are also discussed.

Characterization of used automotive oil filters for recycling

Abstract Most of the over 425 million automotive oil filters used each year in the US are land disposed raising the risk of polluting ground- and surface-water, wasting valuable natural resources, and consuming limited landfill space. Oil filters removed from a vehicle for disposal contain 30–50 wt.% steel and 45–60 wt.% used motor oil depending on the design. Although several different processes are used to recycle used oil filters, an important factor to the recyclability of oil filters is the design of the oil filter. This study examines oil filters to determine the effect of design on the recyclability of oil filters allowing for improved recyclability in future products. The factors that were shown to increase recyclability of filters (higher percentage steel content) were decreasing overall weight, decreasing volume, smaller aspect ratios, and shorter filters.

Thermo-Chemistry of Non-Metallic Inclusions in Ductile Iron

Non-metallic inclusions formed during multi-stage ductile iron melt treatment play an important role in solidification, structure, and casting quality. Professor Carl Loper made fundamental studies on the role of inclusions in heterogeneous nucleation of graphite. In this article, a comparison of inclusions in steel and cast iron was done using thermodynamic calculations (FACTSAGE software) and automated SEM/EDS inclusion analysis (ASPEX system). Statistics of non-metallic inclusions (size, shape, composition) were studied in the iron and steel samples collected by quenching after different stages of melt treatment as well as from castings. The suggested methodology of inclusion analysis has the potential to be applied together with adaptive thermal analysis (ATAS) for solving practical problems such as decreasing shrinkage defects in ductile iron.

Geological Sequestration of CO2 by Hydrous Carbonate Formation with Reclaimed Slag

The concept of this project is to develop a process that improves the kinetics of the hydrous carbonate formation reaction enabling steelmakers to directly remove CO2 from their furnace exhaust gas. It is proposed to bring the furnace exhaust stream containing CO2 in contact with reclaimed steelmaking slag in a reactor that has an environment near the unit activity of water resulting in the production of carbonates. The CO2 emissions from the plant would be reduced by the amount sequestered in the formation of carbonates. The main raw materials for the process are furnace exhaust gases and specially prepared slag.

Analysis of the factors influencing the removal of oil from used automotive oil filters during recycling operations

Abstract More than 425 million used oil filters (UOFs) are discarded annually in the United States. These filters contain an estimated 67 500 m 3 (17.8 million gallons) of used oil that could leach from landfills and pollute soil and water. The Environmental Protection Agency (EPA) has mandated that non terne-plated used oil filters which have been gravity hot drained for at least 12 h are considered non-hazardous and acceptable for landfilling. Filters must be either punctured in the dome end, punctured in the anti-siphon valve, or crushed before draining to meet the requirements for this EPA exemption. This paper evaluates the factors which affect the removal of used oil from UOFs by gravity hot-draining and crushing. The factors studied include oil temperature and viscosity, dome-end puncturing, draining orientation, filter design, time, and crushing force. Of these factors, oil temperature, puncturing of the dome end, filter orientation, and filter design were found to have a significant impact on oil removal by gravity draining. Orientation is very important because an oil filter drained to EPAs recommendations still contains a significant quantity of oil which has a high probability of draining because of normal changes in the orientation of a filter during transport or placement in a landfill. During crushing, oil temperature, filter design, and crushing force were found to significantly impact oil removal.

Recycling used automotive oil filters

Over 400 million used automotive oil filters are discarded in the United States each year, most of which are disposed of in landfills wasting valuable resources and risking contamination of ground- and surface-water supplies. This article summarizes U.S. bureau of Mines research evaluating scrap prepared from used automotive oil filters. Experimental results show that crushed and drained oil filters have a bulk density that is higher than many typical scrap grades, a chemical analysis low in residual elements (except tin due to use of tin plate in filters), and an overall yield, oil-filter scrap to cast steel, of 76% to 85%, depending on the method used to prepare the scrap.