Lubricant Varnish Mitigation

Fluitec International introduces the final chapter in lubricant varnish mitigation (also known as lacquer, sludge or tar). Electrophysical Separation Process™ (ESP) is a patent-pending technology to absorb dissolved and suspended oil degradation products – the cause of varnish. This is accomplished with an oxidatively stable filter media, engineered to selectively remove only the varnish-causing contaminants without disturbing the fluid’s additive system.

How the technology works

The degradation products that make up varnish can exist in the oil in either a dissolved or suspended state depending upon its chemistry and temperature. Eliminating varnish requires that you continually remove these deposits in both physical states. ESP media selectively separates and removes the oil’s bad components (degradation by-products) and leaves behind the oil’s valuable components (additive systems). The degradation products are bonded to the media, removing the risk of soft contaminant leaching. Soft contaminant leaching is common with other varnish removal technologies and can occur with temperature fluctuations in the fluid.

The most critical aspect of solving lubricant varnish is knowing whether the contaminants are in solution or in suspension.  In operating systems with temperatures above 40C, the vast majority of the contaminates are in solution.  Electrostatic oil cleaning, charged agglomeration and depth media filters are designed to remove contaminants that are in suspension, thereby providing limited impact on oils at operating temperature.

ESP is designed to remove degradation products while they are in solution and the fluid is at operating temperature.  The technology will also remove soft contaminants in suspension when the unit is offline and the oil is cool, providing the ultimate protection to your system and a solution to deposits.  This makes ESP a more effective conditioning system compared to electrostatic, agglomeration or depth media absorption systems.

What's the big deal about varnish?

Lubricant varnish has become a significant maintenance problem in many critical applications, such as gas turbines, paper machines and compressors. Turbine oil varnish has been a particularly high profile issue over the last decade. A very small amount of varnish that settles in a susceptible zone, such as a GT’s fuel control or IGV valve can disable the unit from starting properly, resulting in a fail-to-start condition or in some cases a unit trip. In addition to these costly events, varnish can:

• Decrease the effectiveness of heat exchangers, making it more difficult to control fluid temperature
• Increase the wear rates of valve components, load gears, and in some cases, bearing surfaces
• Shorten the lubricant's life by reacting with the antioxidant system
• Cause premature filter change-outs and oil flow restrictions
• Reduced seal life and increased oil leakage

Varnish can negatively impact a plant’s maintenance costs, reliability program and availability. Fluitec has the knowledge and technology to monitor the onset of varnish and solve this issue before it impacts your plant’s operations.

ESP Products

ESP units have been installed on several continents in multiple applications. The units either are designed to be permanently installed (ESP-136) or designed for rotating around your plant’s lubricating assets (ESP-336, ESP-436). ESP units are delivered in a robust system. There are minimal moving parts and little maintenance required resulting in a low cost of ownership. All units in Europe are CE approved.