Using CalSorb for Transformer Oil Regeneration

Transformer Oil Regeneration

With the world becoming ever more environmentally conscious, the dumping and replacement of hydrocarbons have come under the spot light. To try and alleviate the problem suppliers have started looking at recycling spent oil. One of these products that can be very effectively regenerated/recycled is transformer oils.

Transformer oil or insulating oil as it is also known is used in the insulating and heat dissipation of transformers, high voltage capacitors and high voltage switch gear. This oil is very stable at high temperatures which is very important when arresting sparks or electrical arcs. The oil is mainly mineral oil based.

Transformer oil is subject to various electrical and mechanical stresses during the operation of transformers and electrical switch gear. To ensure the safety and effect operation of these equipment pieces transformer oils need to be tested regularly to ensure that the oil is still with in specification.

Oil that is no longer in specification can often be drained and treated with a oil regeneration plant. The regeneration plant aims to do three things. The first is to remove water. This is achieved by heating the oil and placing the oil under vacuum causing the water to boil off while still retaining the oil. Next step aims to remove particulate matter. This is done by using very fine screens and filters. These are typically around 1 to 2 micron filters. 

The last step is the clarification of the oil. Traditionally this is done by passing the oil through columns filled with activated bauxite which is imported into South Africa. Matutu Milling produces a locally manufactured alternative to Bauxite called CalSorb. CalSorb is a heat activated low Volatile Attapulgite based product. Being locally manufactured this product can be supplied at a greatly reduced cost as compared to the imported product. 

The CalSorb has two functions in the Clarification Columns. The first is to form a micro sieve. Attapulgite naturally has a needle like micro structure with fine passages along the grains of the clay. These passages create a very fine sieve adding a next layer of filtration. The second function is clarification. When Attapulgite is heat activated, water is removed from the crystal structure. This process creates charged pockets or pores. These charged pockets act like a magnet capturing heavy metals and other organic impurities. 

After the clarification process is completed the absorbed oil remaining in the column needs to be removed. This is done by a process called regeneration. Unfortunately the clarifier medium, be it Bauxite or Attapulgite, can only be regenerated a certain amount of times before it is no longer effective and has to be discharged.  In local tests Matutu’s CalSorb has shown to handle more regeneration cycles that its competitors thus increasing the amount of times it can be used before it needs to be replaced.

In summary Matutu Milling’s CalSorb is a great locally produced replacement for Bauxite in Transformer Oil Regeneration plants. CalSorb reduces cost as well as increasing the life span of the clarifier medium.

Consider CalSorb in your Regeneration Plant!