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The potential application of bio‐based ester oils for use as lubricants in metal working has been investigated for sustainable production processes in the future. When waste edible and animal fats came into focus as starting materials, it was already proven, that ester oils produced from plant fats performed very well as cooling lubricants. Waste fats were first characterized by analyzing and monitoring samples for one complete year. Inorganic and organic contaminations were found to be low and without seasonal variations. Fatty acid methyl esters (FAME) were produced by transesterification of the waste fats and they were separated into fractions with saturated FAME or unsaturated FAME by fractional crystallisation (winterisation). Further transesterification with 2‐ethylhexanol led to products that could be successfully tested as lubricants. The development of an extraction process aimed at the recycling of oil containing grinding mud by enabling the recirculation of lubricating oil and reutilization of oil‐free metal chips. 相似文献
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Alexandre Lisboa Lago Vagner Roberto Elis Welitom Rodrigues Borges Giovanni Chaves Penner 《Environmental Geology》2009,58(2):407-417
Geophysics has been shown to be effective in identifying areas contaminated by waste disposal, contributing to the greater efficiency of soundings programs and the installation of monitoring wells. In the study area, four trenches were constructed with a total volume of about 25,000 m3. They were almost totally filled with re-refined lubricating oil waste for approximately 25 years. No protection liners were used in the bottoms and laterals of the disposal trenches. The purpose of this work is to evaluate the potential of the resistivity and ground penetrating radar (GPR) methods in characterizing the contamination of this lubricant oil waste disposal area in Ribeirão Preto, SP, situated on the geological domain of the basalt spills of the Serra Geral Formation and the sandstones of the Botucatu Formation. Geophysical results were shown in 2D profiles. The geophysical methods used enabled the identification of geophysical anomalies, which characterized the contamination produced by the trenches filled with lubricant oil waste. Conductive anomalies (smaller than 185 Ωm) immediately below the trenches suggest the action of bacteria in the hydrocarbons, as has been observed in several sites contaminated by hydrocarbons in previously reported cases in the literature. It was also possible to define the geometry of the trenches, as evidenced by the GPR method. Direct sampling (chemical analysis of the soil and the water in the monitoring well) confirmed the contamination. In the soil analysis, low concentrations of several polycyclic aromatic hydrocarbons (PAHs) were found, mainly naphthalene and phenanthrene. In the water samples, an analysis verified contamination of the groundwater by lead (Pb). The geophysical methods used in the investigation provided an excellent tool for environmental characterization in this study of a lubricant oil waste disposal area, and could be applied in the study of similar areas. 相似文献
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