Demulsibility Time of Petroleum Oils

Description

Evaluates the ability of steam turbine and industrial oils to quickly separate from hot water, preventing the formation of stable water-in-oil emulsions.

A power plant's steam turbine operates under conditions of constant oil contact with hot steam. If the oil loses its ability to repel water (demulsify) and forms a stable «oil-water» emulsion, the lubricating film on the colossally loaded bearings will rupture, leading to a multi-million dollar accident. Demulsibility time analysis according to GOST 12068 at the RENA laboratory is a critical test for domestic thermal and nuclear power plants. It will unmistakably show whether your turbine oil is ready for operation, or if its demulsifying additives are exhausted and the fluid requires immediate replacement or separation. Unlike the Western ASTM D1401 method (where water and oil are mixed with a paddle), the GOST 12068 test closely simulates the actual conditions of a steam turbine. An oil sample is placed in a special test tube, which is immersed in a thermostatic bath with a temperature of 90 °C. The most important stage: dry steam is continuously blown through the hot oil. The steam condenses inside the oil, creating a severe, finely dispersed water-in-oil emulsion. Once the emulsion volume reaches a specified level, the steam supply is stopped. The tube is left at rest in the hot bath (at 90 °C). The lab technician, stopwatch in hand, carefully observes the separation process of this mixture. The test is considered complete when the volume of the remaining emulsion between the layers of clean oil and clean water decreases to 3 ml (or disappears completely). The time in seconds it takes for this separation to occur is recorded as the demulsibility time.