New Method Proposed for the Assessment of Lubricant Biodegradability during its Use

Abstract

During operations using biodegradable oil for lubrication, the chemical structure of the biolubricant changes and, as a consequence, its biodegradability tends to decrease. Despite the fact that the biodegradability of most of the fresh biodegradable oils has been well determined, the monitoring of the biodegradability of oil during its aging has not been studied. Thus, the development of a monitoring method for on-line measuring of lubricant biodegradability could provide a significant advance in lubrication and environmental management. In the present paper, the prediction of the biodegradability of a lubricant by means of near infrared (NIR) spectroscopy combined with advanced statistical techniques like PLS is presented. Three fully formulated ester oils and a biodegradable base oil without additives were selected for performing laboratory oxidation in a batch reactor at 140ºC using an air flux and aided by mechanical stirring.During the aging process of the oils, 35 aliquots were sampled at different degradation times, in order to build a mathematical model which allowed the biodegradability of oil to be predicted.

Low Cost Photonic Sensor for in-Line Oil Quality Monitoring: Methodological Development Process towards Uncertainty Mitigation

“…Finally, the sensor includes custom embedded electronics for lighting control and the execution of the oil degradation algorithms. As mentioned before, these algorithms are the result of previous work done on correlating the physical-chemical parameters of the lubricant oil with the colour variations over the ageing time [ 48 , 49 , 50 , 51 , 52 ]. The algorithms are directly implemented in the embedded electronics.…”

“…These tests determine the effectiveness of the system to measure the RGB absorbance of the oil sample and the RGB measurement dynamic range. This RGB measurement is used to calculate the oil degradation condition by applying embedded algorithms based on previously identified correlations between the physical-chemical variables of the lubricant oil and sample colour change [ 48 ].…”

“…This paper describes the development of a photonic sensor to determine oil degradation level based on the colour variation of an oil sample compared to fresh oil. On one hand, there is an important previous work done on correlating the physical-chemical parameters of the lubricant oil with colour variations over ageing time (see Figure 2 ) [ 48 , 49 , 50 , 51 , 52 ]. Based on this scientific background, the proposed sensor will embed algorithms [ 52 ] to provide a general oil degradation index combining the previously defined laboratory parameters (AN, RULER, FTIR, etc.).…”