The right turbine oil provides reliability for power plant
Written by John Sander
Introduction
In recent years, increased demand for electricity has caused power producers to operate their power production turbines differently. In times of heavy need, commonly called peak demand times, they have to push their turbines harder to maximize production. Yet, the cost of fuel sources have continued to increase, so during non-peak times, they either dramatically slow down or completely shut down some of their turbines to reduce fuel consumption and emissions. This type of production is called peaking operating cycle. Within the past few years, many power producers using the peaking operating cycle have realized that they were having turbine operation reliability problems. Coincidentally, in the late 1990s, turbine oil producers began producing newer formula turbine oils. In the laboratory, these new turbine oils looked amazing, but in the field they were not performing as well. Many of the reliability problems seemed to be traced back to the turbine oil.
Since then, a significant amount of research has been conducted, and it has been determined that it is not just one factor; instead, it is a perfect storm of various factors causing these problems. Among the major concerns in gas turbines are oil consumption and the formation of varnish and sludge. Steam turbine operators have experienced increased problems related to foaming, oxidation, loss of water separation and sludge buildup. Subsequent studies have determined that the combination of the new operating conditions and the new turbine oils has resulted in these problems. Fortunately, continued research has begun to point out new ways to help mitigate these problems. One obvious suggestion is to evaluate the current condition of the oil in the unit, and – if the condition is problematic–change the oil.
