Transformer Oil Restoration at Nuclear Power Stations and At Places With Increased Radiation

In a nuclear power station, electrical power is generated by nuclear reactors that make steam for steam driven generating motors. Around the world today, there are approximately 338 nuclear reactors in active service more than 31 different countries.  The world leaders of nuclear power production are the USA, France, Japan, Russia, South Korea, and Germany. Many power industry specialists had at one time placed high hopes on nuclear power for the future even though nuclear power has been associated with many hidden dangers such as follows:
  • uncontrolled reactor runaway (emission of radioactive substances into the environment,  fire damp explosion in a reactor, ground contamination);
  • radioactive emissions into the environment;
  • waste reactors landfill; and the
  • exposure of the plant staff to radiation.
In 1981, in Virginia, at the North Anna Nuclear Generation Station, the failure of the main transformer caused serious damage of other transformers, oil leaks, and a fire. In 1991, in New York, at one of the industrial plants, the damage of the main transformer led to a number of malfunctions and even interrupted emergency power supply. In 2001, in Illinois, at the La Sale County generating plant, the power-generating unit was automatically stopped because of the failure of one of the main power transformers. In 2007, there was a fire at the nuclear power station “Crummel” in Germany, caused by a transformer fault. One of the latest accidents that involves transformer ignition happened at the power-generating unit №6 of the nuclear power station “Fukushima -1″(Japan) in 2012. In 2014, at the Tihange Nuclear Power Station, one of the main transformers began to burn because of it undiscovered damage. These kinds of accidents are too numerous to list and almost all of them were caused by the failures or malfunctions of oil filled electric power transformers.  The above mentioned accidents are evidence that the failures of power transformers may result in the following consequences: fires, radioactive emissions, injuries to the staff, exposure to radiation that is incompatible with life, while undermining the energy security of the country where the nuclear power station is located. The following are the measures that are required to be taken at nuclear power stations to ensure continuous and uninterrupted operation of power transformers and oil reactors:
  • maintenance of loads, voltage, and temperatures within the acceptable limits;
  • monitoring and maintenance of the transformers oil’s performance characteristics at the desired level; and
  • maintenance of cooling and voltage control systems.
There is no doubt that each of the above mentioned aspects are of special importance.  But, special attention should be paid to the maintenance of oil’s performance characteristics within acceptable limits that are realized by reclamation/regeneration (recycling) of oil.  This reclamation process allows for the full restoration of transformer oil that is in service in the power transformer. Transformers with the capacity of more than 1 MVA are serviced with a system of uninterrupted oil reclamation in a thermosyphon or through adsorption filters.  It is also necessary to prevent direct contact of oil with atmospheric air. UVM-10 i n EgyptHaving years of experience, GlobeCore, has designed different types of oil purification and regeneration units. GlobeCore equipment is mobile and that makes it possible to service all transformers used at nuclear power stations with only a small amount of units involved in the processing jobs. GlobeCore regeneration (recycling)  technology ensures complete restoration of all performance characteristics of transformer oil to prolongs its service life and improves the reliability of electric power transformers.   It is transformer reliability that is considered to be a key factor during the operation of nuclear power stations.