Environmental concern and the possibility of energy shortages have drawn attention to means for recovering material and energy resources from waste products. The focus of this thesis is on the application of cost-benefit analysis as a methodological technique for evaluating the economics of resource recovery: namely used lubrication oil. The study initially focuses on the general concern of the economics of resource recovery. This is undertaken primarily by a review of existing literature. An investigation of cost-benefit analysis as advanced by Pearce, Pearce and Dasgupta, Canadian Treasury Board Secretariat, Winch, Nath, Anderson, and Settle, to name a few, reveal a comprehensive and systematic framework for the evaluation of public investment alternatives. Items for inclusion in the analysis are all costs and benefits to every member of, a defined society whose welfare would be affected by the project if implemented. Many goods and services do not enter into the market system, causing difficulty in deriving monetary values for some of the components, especially environmental concerns. For example, the case study reveals two areas: 1) benefit of pollution abatement stemming from resource recovery of used lubrication oil, and 2) costs associated with the improper disposal of the waste products from the recycling process of used lubrication oil. An attempt is made to apply the cost-benefit framework to the case of lubrication oil recycling in the province of British Columbia. Adequate quantitative data were not available, particularly on the social costs and benefits, to fully employ the cost-benefit technique, therefore restricting the analysis in that only an identification of costs and benefits was prepared. When quantification of costs and benefits is not possible, a detailed description of the unquantifiable items indicates to the decision maker the extent of the components. Included in this study is a presentation of the environmental impacts of used oil disposal. The limitations of the cost-benefit analysis as an evaluation technique arise because of limited information and data needed to evaluate, in monetary terms, environmental improvement. Future research could involve a "simulation" of the market to determine a plausible shadow price that gives an indication of what the market price of the item would have been if it had been normally traded. A determination of the price that consumers would be willing to pay for the benefits of pollution control with the knowledge that some pollution would be produced by the recycling activity would aid the analyst in placing values on the costs and benefits. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

M.Tech. (Mechanical Engineering) / This study investigated process development of recovering base oils from waste lithium based lubricating grease using a novel combination of thermal degradation in an aqueous caustic solution and solvent extraction. Lubricating greases consist of a thickening agent dispersed in mineral or synthetic oil, forming a colloidal suspension [1]. Large and increasing volumes of used lubricating oil and grease are produced each year and are considered hazardous wastes. During operation, grease suffers mechanical and thermal degradation [2]. Subsequently, it is regarded as waste and it must be disposed. The waste oil should be collected and recycled not only to prevent the environmental pollution but also to preserve natural resources. Solvent extraction is the preferred method to recycle waste lubricants as it is cost-effective and requires no further purification of the product [3]. The influence of extraction temperature, agitation strength, extraction time, degrading agent concentration, degrading agent-to-grease and solvent-to-sludge mixing ratios on base oil recovery from waste lubricating grease was investigated. This study further optimised the process by studying the influence of various degrading agents (LiOH, NaOH and KOH) and solvents (n-hexane, toluene, heptane, butane, hexanol and acetone) on oil recovery. Oil recovery was enhanced by increase in both extraction temperature, time and agitation speed. The optimum extraction time was found to be 12 minutes. KOH was found to be the optimum degrading agent compared to LiOH and NaOH. Oil recovery also increased from 8.04% to 36.87% with increase in KOH m/m from 5% to 30%. The recovery also increased with an increase of solvent-to-sludge ratio up to 1:6. n-Hexane gave the highest recovery of 74.39% while acetone gave the lowest of 7.43%. A solvent recovery of 82.6% to 88% was obtained through fractional distillation. The study also investigated the differences between virgin and recycled oil using atomic absorption (AA), inductively coupled plasma (ICP) and Fourier transform infrared radiation (FTIR). Rheological studies of waste grease derived oil (WGDO) were also performed. ICP results showed traces of some elements such as Fe, Cu, Si, Ni and Al at a concentration of less than 0.9 mg/L. Oxidation was observed to occur at a band length of 1716 cm-1 while additives were identified at 1670 - 1725 cm-1. The oil viscosity slightly increased with increasing shear rate at temperatures between 60°C and 120°C. The shear rate was varied from 200 to 1000 1/s, with a viscosity convergence at 100°C. A financial economic model was applied to investigate the feasibility of the recycling technology. For 800 kg/day treatment plant, an investment of R 6,031,304.27 is required with a potential return on investment of 40%. Recovery was found to be favourable option compared to landfilling as it offers both economic and environmental benefits.