One
What are the hazards of turbine oil emulsification?


The harm of turbine oil emulsification unit is serious, mainly in the following aspects:


(1) the oil emulsification can adjust valve sleeve and system components such as serious corrosion, because the valve in the control system after the sealing degree is relatively small, resulting in deterioration of the oil control system spool shoulder angle corrosion wear, makes the spool a letter for smaller, thus changing the static characteristics of the speed control system of the final curve. Instability caused by system load swing phenomenon of unit operation. The serious corrosion of the slide valve and sleeve in the regulating system can also cause the slide valve to jam, reduce the sensitivity of the regulating system, and cause the load rejection in the operation of the unit. At the same time, it may destroy the oil film at the bearing and cause the wear of the bearing and journal.


(2) the emulsion is deposited in the oil circulation system, hindering the oil circulation, resulting in insufficient oil supply, excessive bubbles in the oil, affecting the heat dissipation, easily lead to bearing burning tile, there may be serious accidents.


(3) the oil emulsification can accelerate the oxidation of turbine oil, the acid value increase, oxidation to produce more sediment, to further extend the time of steam turbine oil emulsion, which exacerbated the emulsifying oil, forming a vicious spiral.



Two
What are the reasons for the emulsification of steam turbine oil?


There are 3 reasons for turbine oil emulsification: moisture, emulsifier and high speed mixing. Moisture is the main cause of oil emulsification.


(1) the turbine operation, because the unit is not strict, the seal leakage of lubricating oil, poor quality, bearing box and tank vacuum degree is not up to many other factors, is the main cause of the water turbine oil system. At the same time, the installation, operation and other aspects of the unit did not meet the cleanliness requirements of the equipment, the presence of dirt, impurities, etc., will also affect the quality of turbine oil.


(2) the emulsification of turbine oil and water is also related to the additive performance in oil products. A compound or a mixture of turbine oil adding antioxidant and anti rust agent have certain surface activity, the molecular structure of these substances, end with lipophilic nonpolar groups and hydrophilic properties of the other end has a certain surface activity of polar groups. Although they are dissolved in oil but not dissolved in water, the polar group has a certain affinity to water at a certain speed.


(3) when the turbine rotates at a high speed, the oil and water emulsion is fully stirred, these hydrophilic polar groups have the opportunity to fully pro with water. When the affinity is large, and will firmly shuilao together. Because the lipophilic non-polar group can be dissolved in oil, the water and oil can be combined by the action of this substance. Therefore, the water can not be separated from the oil, that is, emulsification phenomenon. If the affinity is weak, water and oil can be separated.  The turbine oil additive added to ensure and improve the quality, improve the anti emulsifying properties, reduce or remove hydrophilic properties of strong additive ingredients, anti emulsifying properties index reaches or exceeds the standard of turbine oil.


Three
Prevention and treatment measures of steam turbine oil emulsification


To ensure the design, manufacture, installation, operation and maintenance of steam turbine unit as well as the quality of steam turbine oil, it is very important to prevent and eliminate the water in the turbine oil system and prevent the emulsification of the turbine oil. Therefore, we should pay attention to the following aspects:


(1) to ensure the quality of product design and manufacture. The design is unreasonable, the product manufacturing does not meet the design requirements, directly leading to the turbine oil system water inflow.


(2) the oil purification device should be put into operation regularly during the operation of the unit, and the oil-water separation and impurity filtration should be carried out in time for the regulating and lubricating oil in the turbine generator group oil system. At the same time, the oil system components to ensure the equipment parts cleaning, sealing in the manufacture and installation and operation, the size of repair to ensure that all parts of the oil system is clean, free of impurities and water pipe system, and other foreign bodies, the cleanliness of the factory shall comply with the provisions of the various standards of cleanliness.


(3) the turbine oil purchased must meet the technical specifications specified in the national standard GB7596-2000, especially the anti emulsification performance and acid value index must be guaranteed. At the same time, turbine oil in use should be in accordance with "L-TSA turbine oil change index SH/T0636-1996" regulations, regular sampling inspection, found problems, take timely measures.


(4) the emulsified oil of emulsified turbine oil can also be added to the oil to improve the anti emulsification performance of the turbine oil. The demulsifying agent is used to destroy the emulsion film on the oil-water interface, and the water is released to achieve the purpose of water removal.


(5) the unit overhaul, strictly control the unit seal clearance, to ensure the unit overhaul cycle, unit operation, operation personnel due to strengthen the adjustment of the seal leakage according to the load condition, prevent oil in water caused by large seal leakage.


(6) in the operation of the unit, the main fuel tank should be regularly discharged, and the oil-water separation of the regulating and lubricating oil in the turbine generator unit oil system will be carried out in time.


In short, reducing the metal particles in the turbine oil and avoiding oil emulsification are important to ensure the safe operation of the steam turbine. The key to solve the problem of turbine oil emulsification is strictly control from the aspects of product design, manufacture, installation, operation and maintenance, as well as the quality of steam turbine oil.