Preface The turbine oil system is used to provide sufficient, high-quality lubricating oil to the bearings of the turbine generator set and pressurized oil to the regulating system, as well as supplying oil to the turning gear and jacking device during unit turning. Therefore, the quality of the turbine oil is an important indicator affecting the safe operation of the turbine. Oil emulsification will cause corrosion of the oil system and rust on unit components. At the same time, the turbine oil will also lose its lubrication, heat dissipation, and speed regulation functions, seriously affecting the safe operation of the unit. [b]1 Turbine Oil Quality Requirements[/b] The turbine oil system requires that the turbine oil used must be high-quality, homogeneous refined mineral oil, and must contain anti-corrosion and anti-oxidation components. In addition, the oil must not contain any harmful impurities that affect performance. The turbine oil system designed and manufactured by Harbin Turbine Co., Ltd. uses 32L-TSA turbine oil, which is formulated from deeply refined base oil and formulated with antioxidants and rust inhibitors. According to national standard GB 11120-89, this oil should meet the following requirements: Kinematic viscosity (40℃): (28.8～35.2) mm2/s Flash point (open cup): Not lower than 180℃ Mechanical impurities: None Demulsification value (40-37-3) mL: Not greater than 15min (at 54℃) Foaming test 24℃: Not greater than 450mL/0mL 93℃: Not greater than 100mL/0mL After 24℃: Not greater than 450mL/0mL Acid value after oxidation reaching 2.0mgKOH/g: Not less than 3000h Liquid phase corrosion test (synthetic seawater): No rust copper strip test (100℃, 3h): Not greater than Grade 1 [b]2 Causes of turbine oil emulsification[/b] There are generally three causes of turbine oil emulsification: water, emulsifiers, and high-speed agitation. Among them, water is the main cause of oil emulsification. During turbine unit operation, numerous factors, including inadequate shaft seals, steam seal leaks, poor lubricating oil quality, and insufficient vacuum in the bearing housing and oil tank, are the main causes of water ingress into the turbine oil system. Simultaneously, failure to meet equipment cleanliness requirements during installation and operation, resulting in the presence of dirt and impurities, will also affect the quality of the turbine oil. The emulsification of turbine oil and water is also related to the performance of additives in the oil. Antioxidants and rust inhibitors added to turbine oil are mostly compounds or mixtures with certain surface activity. In their molecular structure, one end has a non-polar group with oleophilic properties, and the other end has a polar group with certain surface activity and hydrophilic properties. Although they are soluble in oil but not in water, at certain speeds, the polar group has a certain affinity for water. When the turbine rotates at high speed, and the oil and water are thoroughly mixed to form an emulsion, these hydrophilic polar groups have the opportunity to fully bind with water. When the affinity is strong, they will bind firmly to the water. Furthermore, because lipophilic nonpolar groups can dissolve in oil, water and oil can combine through the action of this substance. Therefore, water cannot separate from oil at this time, i.e., emulsification occurs. If the affinity is very weak, water and oil can separate. Therefore, it is required that the additives added to turbine oil must ensure and improve their quality, improve their anti-emulsification performance, reduce or remove the components with strong hydrophilic properties in the additives, and meet or exceed the anti-emulsification performance indicators specified in the turbine oil standard. [b]3 Hazards and Treatment Measures of Turbine Oil Emulsification[/b] 3.1 Hazards of Turbine Oil Emulsification Turbine oil emulsification brings serious harm to the unit, mainly in the following aspects: 1. Turbine oil emulsification can cause severe corrosion of components such as slide valves and sleeves in the regulating system, causing slide valve jamming, reducing the sensitivity of the regulating system, and even causing load shedding during unit operation. At the same time, it may also damage the oil film at the bearing, easily causing wear of the bearing and journal. 2. Emulsion deposits in the oil circulation system, hindering oil circulation, causing insufficient oil supply, affecting heat dissipation, and easily leading to bearing failure, potentially resulting in serious accidents. 3. Turbine oil emulsification accelerates turbine oil oxidation, increases acid value, and produces more oxide deposits, further prolonging the demulsification time of the turbine oil. 3.2 Remedial Measures The consequences of turbine oil emulsification on unit operation are serious. Ensuring the design, manufacture, installation, operation, and maintenance of turbine unit equipment, as well as the quality of turbine oil, is crucial for preventing and eliminating water ingress into the turbine oil system and preventing turbine oil emulsification. Therefore, the following aspects should be emphasized: 1. Ensure product design and manufacturing quality. Unreasonable design and product manufacturing that do not meet design requirements directly lead to water ingress into the turbine oil system. 2. During unit operation, an oil purification device should be activated to promptly separate oil and water and filter impurities in the regulating and lubricating oils in the turbine generator set oil system. Meanwhile, during the manufacturing, installation, and operation of oil system components, it is essential to ensure that the equipment components are clean and sealed, meeting all cleanliness standards specified by the manufacturer. 3. Purchased turbine oil must meet all technical indicators specified in national standard GB 11120-89, especially the demulsibility and acid value indicators, which must be guaranteed. Furthermore, during use, turbine oil should be sampled and inspected regularly according to the "L-TSA Turbine Oil Change Index SH/T0636-1996," and any problems should be addressed promptly. 4. For emulsified turbine oil, power plants may also add demulsifiers to improve its demulsibility, depending on the situation. Demulsifiers break down the emulsion film at the oil-water interface, releasing water and achieving water removal. [b]4 Conclusion[/b] Preventing turbine oil emulsification plays a crucial role in ensuring the safe operation of turbines. The key to solving the problem of turbine oil emulsification lies in strict control over aspects such as product design, manufacturing, installation, operation and maintenance, as well as the quality of turbine oil.