SU1753370A1 - Method of determination of solid matter in engine oils - Google Patents

Abstract

Usage: the invention relates to methods for monitoring the purity of petroleum products and can be used to determine the content of solids in motor oils. SUMMARY OF THE INVENTION: The viscosity g and the electrical conductivity G of the oil are measured at temperatures of 20-30 and 95-100 ° C before and after filtration. The concentration of mechanical impurities is determined by the formula: m tf () - 1 / (4) 1 - (|) 2, where tf is the concentration of the mechanical impurities determined by filtering by filter weight, () 1, () 2 - conductivity and oil viscosity before and after filtration at a temperature of 95-100 ° C, (617) 1, (G ifti - electrical conductivity and oil viscosity before and after filtration at a temperature of 20-30 ° C. 1 tab.

Description

The invention relates to methods for monitoring the purity of petroleum products and can be used to determine the content of mechanical impurities in motor oils.

There is a known method for determining the concentration of a dispersed phase in liquids, including gravitational sedimentation of a solid phase in a cylindrical resonator, determining the time of sedimentation and, through them, the concentration of mechanical impurities.

This method is applicable at a rather high concentration of contaminants, and, in addition, mechanical impurities of oils have significant gravitational stability.

The closest solution to the technical essence and the achieved result to the invention is the method of mass determination of mechanical impurities, according to which a portion of contaminated oil diluted with gasoline B-70 is filtered through an Red Ribbon ashless paper filter, weighed before and after analysis. The method has low accuracy, since the Red Ribbon filters have a pore size of 10-15 µm, and therefore smaller particles are not retained by them.

The purpose of the invention is to improve the accuracy of the analysis.

The goal is achieved by measuring the viscosity (ij) and electrical conductivity (G) of the oil at 20-30 and 95-100 ° C before and after filtration and determining the concentration of mechanical impurities by the formula.

ss

m

- --andЈЈ 1 h. (1)

, C n, Gn

fruip Csip2

where tf is the concentration of mechanical impurities, determined by filtering by mass of the filter;

(G;) i, (G if) i - electrical conductivity and viscosity of the oil before and after filtration at 95-100 ° С;

(Gj /) i, (Grfe is the electrical conductivity and viscosity of the oil before and after filtration at 20–30 ° C.

The method is carried out as follows.

During the operation of engine oil, mech-membranes accumulate in them — products of incomplete combustion of fuel, destruction of oil molecules, and abrasive particles. In order to ensure the sedimentation stability of these particles, dispersing-stabilizing additives with polar properties are added to the oil. The molecules of these additives are adsorbed on the surface of the particles of the dispersed phase and prevent their coarsening and sedimentation.

When the oil is heated, desorption of part of the additive molecules occurs. These additives in oils are well soluble and increase its electrical conductivity. When the oil is heated, its conductivity increases, which is associated with a decrease in the viscosity of the oil. The product of these quantities remains approximately constant over a wide range of temperatures for pure products and increases with the presence of impurities.

EXAMPLE 1. The viscosity and electrical conductivity of the used oil were measured before and after filtration with a sealed Ms 90 paper filter and a Red ribbon filter at various temperatures. Ogts were also added with the addition of coagulant to motor oil. In parallel, experiments were carried out to determine the concentration of mechanical impurities by changing the mass of the filter when filtering a sample of oil by a known method. The results of the experiments are given in the table.

When filtering, a part of the mechanical impurities passes through the filter, and low results are obtained. This is due to the fact that a certain part of the impurity particles has a size smaller than the filter pores. By adding coagulant to waste oil, you can increase the size of the impurity particles. Determining the content of solids by filtration using coagulant gives more accurate results.

Ethanol was used as a coagulant for mechanical impurities of motor oils. The use of coagulant does not ensure the coagulation of all existing small particles and not all of them will be trapped by the filter. The table shows that the product g} G begins to increase from 70 ° C and increases significantly to 100 ° C. Therefore, as the upper temperature range

95-100 ° C should be used. The lower temperature range is 20-30 ° C, although the product of G remains unchanged up to 50 ° C.

Example 2. The calculation of the content of mechanical impurities by the formula (1) for the temperature range of 20-30 and 100 ° C gives for filters (36) and (Sv) 1.6 and 1.5%, respectively. At an upper temperature of 95 ° C, 1.65 and 1.6% are obtained, respectively.

A temperature of 70 ° C is not suitable for use as an upper limit.

The application of the proposed method provides the following advantages in comparison with the known ones: an increase in the accuracy of determining the content of mechanical impurities in motor oils due to their fuller accounting, the possibility of separating all impurities into fine and coarse particles.

Claims (1)

The invention of the method for determining the concentration of mechanical impurities in motor oils by changing the mass of the filter when filtering an oil sample, characterized in that, in order to improve the accuracy of the analysis, the viscosity and electrical conductivity of the oil are additionally measured at 20-30 and 95-100 ° C before and after filtration and determine the concentration of solids by the formula m  FGG0- - 11 . "". -I -G n v .G n -Gip1 - c-gf where is the concentration of mechanical impurities, determined by filtering by mass of the filter; . () i, (G1 jy) 2 — electrical conductivity and viscosity of the oil before and after filtration at 20–30 ° C; () i, (G rfp. - electrical conductivity and viscosity of the oil before and after filtration at 95-100 ° C.